Handbook of Anti-Aging Medicine

By Prof Dr Mike KS Chan, Arseniy Trukhanov and Vittorio Calabrese

This handbook focuses on different aspects of anti-aging and both preventive and regenerative medicine. It includes analysis of the paradigm of ageing and concepts of anti-aging medicine.

Standards and technologies are highlighted in over twenty chapters all authored by international experts in regenerative medicine.

Topics covered include:
• Ageing, aging, and anti-aging: A Decalogue for anti-aging medicine
• Lessons from Sicilian centenarians for anti-aging medicine
• Molecular biomarkers and genetic aspects of aging
• Future of peptides in clinical practice
• Mitochondrial approaches in anti-aging medicine and in SARS-CoV2 infection
• Tissue-specific autoantibodies in preventive medicine
• Chronic stress as a psycho-neuro-immunological dysfunction
• Gut-associated immune system and its health implications
• Regenerative medicine with platelet-rich-plasma
• Alzheimer’s disease: Preventive and anti-aging neurology
• Autistic spectrum disorder and mitochondrial medicine
• Integrative hormonal approach in anti-aging medicine
• Preventive cardiology and phlebology
• Aesthetic and anti-aging medicine
• Preventive ophthalmology
• Preventive oncology
• Nutrition in healthy aging
• Physical activity and fitness paradigms for anti-aging and longevity

Recommended reading for clinicians working in anti-aging medicine as well as ageing people. The authors hope it will set a new “standard of anti-aging medicine” and as a tool in planning for the inevitable challenges we all will face caring for ageing patients and creating preventive-health programs.

• Language: English
• Publisher: EUROPEAN WELLNESS ACADEMY
• Release date: Jan 16, 2023
• ISBN: 9781662930218

Book preview

Preface

The rapid progress of the past three decades

has led to the geroscience field near a point

where human interventions in aging are plausible

Joseph C. Kruempel,

Computational tools for geroscience

(www.keaipublishing.com/TMA)

There is one official definition of health provided by WHO. However, we can find many answers to the question, What is anti-aging medicine about?

The easiest solution is asking A4M, the American Academy of Anti-Aging Medicine, which gave start to anti-aging movement in 1992. In 2012, they published Encyclopedia of Clinical Anti-Aging Medicine & Regenerative Biomedical Technologies (www.worldhealth.net). They suggested the following definition: medical specialty founded on the application of advanced scientific and medical technologies for the early detection, prevention, treatment and reversal of age-related dysfunction, disorders and diseases. The education based on this concept has been spread through 120 countries, providing more than 30,000 physicians with their diplomas. The co-founders of A4M began their careers in Sports Medicine, which has definitely impacted their model: keep the body functioning at its peak for maximizing the healthy human lifespan.

The European Society of Anti-Aging Medicine (esaam.ecopram.eu) was originally established in 2003 in Paris as subsidiary of A4M. In 2006, it became independent by new registration in Vienna, where it organized the first European Congress on Preventive, Regenerative and Anti-aging Medicine (ECOPRAM). The founders of ESAAM came from both science and clinical medicine: gerontology, physiology, biochemistry, dermatology, endocrinology, and aesthetic medicine, thereby influencing the ESAAM model. The ESAAM model used biomedicine from molecular-genetic diagnostics to personalize interventions of 4P (personalized, preventive, predictive and precision) medicine. The goal of the ESAAM protocol is to optimize functional parameters based on early biomarkers of age-related diseases, epigenetic and biopsychosocial models. This model came from physical and rehabilitation medicine (ISPRM) and a basic document ICF approved by WHO in 2001. Our goal is not to find the disease according classification ICD-10 and treat it by traditional clinical medicine, but to use preclinical prevention medicine to manage early symptoms and risks associated with age-related diseases. These concepts are similar to the concepts of Uni-Age of Japanese Society of Anti-Aging medicine: both involve monitoring of future longevity from childhood with the creation of the microbiome with no age limits for personalized protocols.

The goal of ESAAM is not to create a new medical specialty. ESAAM is based on taking a multidisciplinary approach when a physician monitors the health of the patient and coordinates the activities of endocrinologists, dermatologists, aesthetic medicine doctors, cardiologists and angiologists, neurologists, traumatologists, ophthalmologists and dentists. As the result of the anti-aging program, the absence of diseases can lead to optimal function and high quality of physical and social longevity.

The decision to write this handbook was motivated by the need to share our basic knowledge of 4P medicine with doctors in clinical medicine, which is still limited by the demands of insurance industry, ICD-10 classifications and population statistics protocols. The main questions we tried to answer are as follows: What are the theoretical bases of age-related diseases and how we can diagnose and correct age-associated dysfunctions?

The book is separated into 4 parts:

Part One, Theoretical aspects of anti-aging medicine, is dedicated to the meaning and difference of ageing and anti-aging, gerontology aspects based on the lessons from Sicilian centenarians, genetic and genomic aspects of aging and active longevity, the significance of molecular biomarkers of aging for preventive medicine, the role of immunology profile and gut-associated immune system, the mechanisms of mitochondrial dysfunction and hormesis, stress diagnostic and therapy, and influences of protocols of personalized interventions.

Part Two, Advances in regenerative and aesthetic medicine, presents current advancements in peptide therapy, clinical protocols for platelet reach plasma technology, the future of aesthetic medicine with recombinant growth factors as the next step of PRP technology and molecular biomarkers of skin aging for personalized aesthetic interventions.

Part Three, Personalized preventive medicine, highlights the basic symptoms, risk and biomarkers of age-related diseases in cardiology, neurology, oncology, phlebology, ophthalmology and endocrinology while expressing the long term practical experience of clinicians in each field.

Part Four, Methods and technologies for personalized interventions, describes the advances and the role of hormesis and nutrition in healthy ageing, vegetable oils for antioxidant therapy, the current paradigms of physical activity and fitness and drugs for personalized interventions with potential anti-aging effects.

This handbook does not claim to answer all theoretical and practical questions reflecting the needs of translation medicine from geroscience to practical protocols of anti-aging medicine. Instead, it opens the ESAAM publication series, which should cover basic aspects of current panels of aging biomarkers, methods and technologies for early detection of age-related dysfunctions, principals and protocols of health monitoring in anti-aging programs, the structure, technologies and staff of future anti-aging medicine clinics, potential advances of regenerative medicine and stem cells therapy, symbiosis of wellness, and medical spa and fitness in anti-aging clinics.

The anti-aging medicine is nearly 30 years old. Now is the time for the new fellows to promote the new concept of healthy ageing and optimum functioning for physical and social longevity.

Arseniy Trukhanov

Mike K.S. Chan

Part 1.

THEORETICAL

ASPECTS

OF ANTI-AGING

MEDICINE

CHAPTER 1

Ageing, aging and anti-aging: A physiological perspective and a Decalogue for anti-aging medicine

Manuel J. Castillo

Professor of Medical Physiology, Faculty of Medicine, University of Granada, Granada, Spain

Scientific President of the Spanish Society of Anti-aging and Longevity Medicine

e-mail: [e-mail]

Ageing

There is important terminological confusion regarding the terms ageing and aging, the same which goes for the terms anti-aging and anti-ageing. In fact, they are used indistinctly to describe the same phenomena. Under a physiological perspective, these terms are not strictly equivalent; some of them are improperly used, as is the case for the expression anti-ageing.

Ageing is a natural, generalized and inevitable process. Ageing is the consequence of the passage of time. This passage of time for humans may have positive or negative effects. Human age starts at birth. During initial life stages, the passage of time (i.e. ageing) has unequivocal positive effects in body structures and functions. During childhood, adolescence and early adulthood, ageing is associated with growth, development, maturation and general improvement in physiological function that lead to gains in specific and overall functional capacities. These gains are influenced by constitution and external socio-economic factors, including lifestyle. The final level attained in functional capacities varies from one individual to another.

Once maximal function is attained during early adulthood, a relentless and variable decline in functional capacity begins. These progressive losses of physiological functions differ among individuals and among different functions within the same individual. Some functions and individuals are less affected (age well), while other functions and individuals are more affected (age worse), worsening over time. This differential susceptibility depends on multiple factors, both intrinsic (genetic, constitution, etc.) and extrinsic (diseases, lifestyle, etc.). Consequently, any individual is both a passive and an active subject of the ageing process. Ageing also affects the personal and relational characteristics of the individual. Ageing is easily appreciable: it is perceived by the person who ages and it is perceived by others, and both perceptions are inter-influenced.

Aging

Aging can be defined as, and its use should be restricted to, the negative consequences of the ageing process that occur during middle-late adulthood and senescence. In fact, once maturation is attained, ageing determines structural disorganization and loss of functionality. In physical terms, it corresponds to an increase in entropy. Human beings are particularly sensitive to this entropy increase given their high level of organization and complexity both in structural and functional terms. Aging can therefore be interpreted as a deterioration of body structures and functions associated with the ageing process during adulthood and senescence. Skin or body composition, and their deterioration, are easily perceived. Similarly, the rest of the tissues, organs and systems also age, their functions deteriorating, although it is less clearly perceived. In fact, their deterioration only becomes apparent when its ability to adapt to external stressors is impaired or when the level of deterioration is sufficiently advanced. For example, the skin ages and it is readily seen; the brain or the kidney age similarly, but being internal, they are not so easily observed. It can become apparent by using specific tests or when the degree of functional impairment is high.

Anti-aging

Ageing is an inevitable process. It cannot be opposed, but its deleterious consequences (aging) can be either accelerated or slowed down. This may occur regardless of the characteristics of the person. Slower aging means less aging, better resistance of the passage of time, limiting the negative consequences of the ageing process. This is, literally, anti-aging. Under a physiological perspective, the term anti-ageing is not correct since the passage of time cannot be opposed. By contrast, we can oppose its negative consequences.

For some specific structures or functions, the aging process could even be virtually stopped. This occurs, for example, when replacing an organic structure with an artificial one that is resistant to the passage of time and entropy increases. This is the case of crystalline lens replacement in the case of cataracts. For that particular function by changing the lens we have prevented aging, this is actual anti-aging.

Even more, for some structures or functions, it is also possible to ameliorate integrity and functionality. By doing that, structure or function are taken to a level corresponding to younger age. Consequently, a functional or adaptive capacity that could be partially lost or never attained can now be regained. Two examples illustrate this concept:

1) Expression wrinkles are a consequence of aging. If we correct them with botulin toxin, the person acquires a younger appearance. Therefore, for that structure and function, aging has been literally reversed.

2) Muscle strength is lost over the years; this is a negative consequence of age. With a proper training program, strength and muscle mass can be regained, attaining the level of a younger age or even getting a mass or strength never accomplished before. This is another example in which aging has been reversed.

Finally, with age and deterioration of functional capacity, a wide range of age-related processes or diseases appears, most of them degenerative in nature. Their severity and impact on health are highly variable. Some of these deteriorations have little health repercussions. For example, greying or loss of hair and loss of agility have few repercussions. In other cases, the consequences are more significant, such as progressive hearing or vision loss or loss of libido. Other deteriorations are even more serious and limiting, such as cognitive decline, kidney failure, loss of cardio-respiratory capacity or limited mobility and autonomy.

Aging associated conditions that attract the most attention and require adequate health care are those limiting autonomy, which cause suffering and mortality. These include neurodegenerative diseases such as Alzheimer’s disease, atherosclerosis, cardiovascular diseases, metabolic diseases or various forms of cancer. Many of these diseases have and even share various risk factors such as smoking, overwhelming stress, lack of exercise or inadequate nutrition. Controlling these risk factors, preventing the development of these degenerative diseases, attenuating or minimizing their consequences and even treating them are also examples of anti-aging medicine.

Anti-aging medicine

Anti-aging interventions aim to attenuate, partially stop or even temporarily reverse the consequences of aging or age-associated functional decline in order to prevent or limit age-associated diseases. This can be achieved with a set of interventions included in the category of anti-aging medicine.

The objective of anti-aging medicine is mainly to extend the health-span that is the number of years being lived in good health with autonomy and good quality of life. By that, an increase in life-span will also occur, although this is secondary to the increase in health-span. Anti-aging medicine differs from geriatrics mainly regarding the age of the patient.

The patient in anti-aging medicine is typically a healthy young or middle-aged person without age-associated disease who wishes to have successful ageing and a prolonged health span. The patient in geriatrics is typically an old or middle-aged individual presenting age-associated diseases that require medical care. A practical and simple example illustrates the differences and the coincidences between both medical specialties. Gerontology is the science studying the biological, psychological and social aspects of aging. A drug that can be used in geriatrics and anti-aging medicine is metformin. In geriatrics, it is used to treat (age-associated) type 2 diabetes due to its hypoglycemic effects. In anti-aging medicine, metformin is used to prevent multiple age-associated health problems, one of which is impaired glucose tolerance and diabetes.

Surpassing 100 years of age with autonomy and good health is a feasible goal in strictly physiological terms. In fact, it is already a reality for a limited number of people. This reality can be extended to many others, or even to a majority, of the western population. This is already the case in certain areas of the planet, which are called blue zones. Achieving the goal mentioned above is not an easy task and requires the knowledge and commitment of all parties involved in the process. Extending this age limit much further will require the help of advanced technology and biotechnology that is not presently available.

With today’s knowledge and technology, we here propose a generic Decalogue of anti-aging treatments and practices readily available in anti-aging medicine.

Decalogue of interventions in anti-aging medicine

• To protect the organism and its different functional structures from toxins and circumstances which accelerate aging.

• To improve functional capabilities (as many and as much as possible). This is directly anti-aging.

• Attitude to aging and anti-aging.

• Being active and social.

• Anti-aging nutrition is a specific way to eat beyond a healthy diet.

• Anti-aging entails physical and mental exercise, followed by adequate rest and recovery, including good quality sleep.

• Anti-aging uses nutritional supplements that have been shown to be positive for health and well-being have protective effects.

• Anti-aging uses drugs that have been shown to have protective effects, improve functional ability, and to be positive for health and well-being.

• Comprehensive disease prevention, control of risk factors and early diagnosis and treatment of age associated diseases, are premises of anti-aging medicine.

• All individuals should assume the years and their consequences and to enjoy life in its different stages.

Epilogue

Anti-aging medicine is not, and has long ceased to be goodism, a catalogue of good intentions, a light form of medicine of good wishes, or an impossible preventive medicine of otherwise inevitable age-associated diseases.

Anti-aging medicine is a diagnostic and therapeutic reality like any other medical intervention. This kind of medicine has multiple therapeutic arsenals based on scientific evidence that direct its activity to aging. Like the rest of medical interventions, its effectiveness varies from one person to another and from one moment to another within the same person.

Anti-aging medicine is not, nor can it be, a banal, frivolous or opt-out medicine. It is a complex activity with great responsibility and enormous social and health repercussions worthy of being chosen both individually and collectively. Living in good conditions for many years, i.e. preventing aging and its consequences, is important. Assuring health and autonomy into very old age, and reducing the social and economic cost of old age and its associated diseases, decreasing dependency and the level of care that older people require is based on whether aging and the prevention of its consequences are taken seriously. It is not only individual health and well-being that are at stake, but is also social well-being. The goal is to increase the population’s health-span.

References

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Barbi, E., Lagona, F., Marsili, M., Vaupel, J.W., Wachter, K.W. (2018). The plateau of human mortality: demography of longevity pioneers. Science. 360, 1459–1461.

Buettner., D., Skemp., S. (2016). Blue Zones. Lessons From the World’s Longest Lived. Am J Lifestyle Med. 10, 318–321.

Chmielewski, P.P. (2020). Human ageing as a dynamic, emergent and malleable process: from disease-oriented to health-oriented approaches. Biogerontology. 21, 125–130.

Cohen, A.A., Legault, V., Fulop, T. (2020). What if there’s no such thing as ‘‘aging’’? Mech Ageing Dev 192:111344.

de Grey AD (2013) The desperate need for a biomedically useful definition of ‘‘aging.’’ Rejuvenat Res 16:89–90.

Faragher RGA (2015) Should we treat aging as a disease? The consequences and dangers of miscategorisation. Front Genet 6:171.

Flatt, M.A., Settersten RA Jr., Ponsaran, R., Fishman, J.R. (2013). Are Anti-Aging Medicine and Successful Aging Two Sides of the Same Coin? Views of Anti-Aging Practitioners. J Gerontol B Psychol Sci Soc Sci. 68, 944–955.

Gems, D., de Magalhães, J. P. (2021). The hoverfly and the wasp: A critique of the hallmarks of aging as a paradigm. Ageing research reviews, 70, 101407.

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Mitnitski, A., Howlett, S.E., Rockwood, K. (2017). Heterogeneity of human aging and its assessment. J Gerontol. – Ser. A Biol. Sci. Med. Sci. 10.1093/gerona/glw089

Ukraintseva S., Arbeev K., Duan, M., et al. (2020). Decline in biological resilience as key manifestation of aging: Potential mechanisms and role in health and longevity. Mech Ageing Dev. 194, 111418.

CHAPTER 2

Lessons from Sicilian centenarians for anti-aging medicine

Calogero Caruso¹, Giulia Accardi¹, Anna Aiello¹, Stefano Aprile¹, ², Giovanni Duro³, Damiano Galimberti⁴, Mattia Emanuela Ligotti¹, ³, Giuseppina Candore¹

¹ Laboratory of Immunopathology and Immunosenescence, Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, Palermo, Italy

² Unit of Transfusion Medicine, San Giovanni di Dio Hospital, Agrigento, Italy

³ Institute for Research and Biomedical Innovation, National Research Council, Palermo, Italy

⁴ Italian Association of Anti-Ageing Physicians, Milan, Italy

Corresponding to: Prof. C. Caruso

Italian Association of Anti-Ageing Physicians, Milan, Italy

e-mail: [e-mail]

Introduction

People around the world are living longer. However, the pace of ageing is also increasing (WHO, 2021). The ageing of the population has great social and economic consequences. The increasing mean lifespan of the population is a success of humanity, but also poses a challenge. Ageing is associated with increased susceptibility to disability and to many diseases like cardiovascular diseases (CVDs), cancer, type 2 diabetes, Alzheimer (AD), Parkinson Disease (PD) and infectious diseases as further demonstrated by the COVID-19 pandemic (Franceschi and Campisi, 2014; Licastro et al. 2005; Vasto et al., 2007; Ligotti et al., 2021a). From epidemiological studies, we know that 15-35% of people aged 75 and over in the Western world require some form of daily care due to the loss of the ability to carry out activities (Beard et al., 2016). Therefore, the increase in the duration of life, lifespan, does not coincide with the increase in the duration of health, healthspan, i.e., the period of life free from serious chronic diseases and disabilities (Crimmins, 2015).

Thus, it is necessary to fully understand ageing mechanisms to prevent its detrimental aspects. Efforts to understand ageing have suggested the need to distinguish ageing from age-related diseases. However, this is not true because, in protected environments, humans and animals die because of age-related diseases that are manifestation of ageing. However, these last years can keep an unprecedented promise to increase health span by preventing, delaying or, in some cases, reversing disability and age-related diseases, i.e., to age successfully (Caruso et al., 2021a; Longo et al., 2015).

There are two ways to become old, without success (unsuccessful ageing), manifested by people that develop one or more age-related diseases, and with success (successful ageing), defined as the process of developing and maintaining the functional ability, which enables well-being in older age. Accordingly, successful ageing involves either late onset or avoidance of disability and age-related disease including CVDs and other organ specific diseases. In addition, it is characterized by preservation of desirable cognitive and physical function, and social activities throughout the life-span (Aiello et al., 2019a; Avery et al., 2014; Kolovou et al., 2014).

Slowing ageing at the molecular and cellular levels should enhance the attainment of successful ageing, as demonstrated by centenarians that avoid or at least delay (or survive to) clinical manifestation of chronic diseases and disability. Therefore, the study of centenarians is crucial to understand the mechanisms involved in ageing and age-related diseases (Accardi et al., 2019a; Caruso et al., 2012; 2019; Caruso and Puca, 2021).

The ageing process is driven by a lifelong accumulation of molecular damage, resulting in gradual increase in the fraction of cells and organs carrying defects. As people get older, the increased levels of damage interfere with both the performance and functional reserves of tissues and organs, resulting in a breakdown of self-organizing system and a reduced ability to adapt to the environment. Frailty, disability, and age-related diseases follow. Maintenance mechanisms slow the rate of damage accumulation (Accardi et al., 2019a).

Why humans can develop age-related diseases is a puzzle that is worth seriously studying. However, an even more fascinating enigma lies in understanding how some subjects are able to live for a century. Genetics, epigenetics, sex and gender, socio-economic and educational status, chance and life circumstances, nutrition and physical activity, stress management, social support and pathogen load all contribute to positively or negatively modulate these maintenance mechanisms. Different combinations of these factors create the possibility to avoid age-related pathologies and become centenarians. For the prevention of age-related diseases, it would be potentially interesting to develop medical interventions that would allow us to replicate the biology of centenarians in the average person (Accardi et al., 2019a).

Moreover, the deep study of the so-called hallmarks of ageing offers new scenarios and possible therapeutic approaches in the ageing treatment. The hallmarks of ageing, defined by López-Otín et al. in 2013 as the nine factors that contribute to ageing and together determine the ageing phenotype, are classified in three clusters:

• the primary hallmarks (genomic instability, telomere attrition, epigenetic alterations and loss of proteostasis) that represent the main causes of molecular damage;

• the antagonistic hallmarks (deregulated nutrient-sensing, mitochondrial dysfunction and cellular senescence) that show beneficial effects at low levels but become deleterious at high levels;

• the integrative hallmarks (stem cell exhaustion and altered intercellular communication) that appear as a consequence of accumulating damages no longer compensable by homeostatic mechanisms.

Lifestyle has been demonstrated to influence all these hallmarks, at least partly, often involving the same molecular targets. These hallmarks and their interconnectivity should serve as an evaluation tool to assess and prioritize interventions that can be deemed effective in slowing ageing and preventing age-related diseases.

In the last twelve years, we have surveyed the population of some Sicilian inland towns characterized by a high rate of centenarians to investigate the mechanisms involved in longevity (Accardi, 2019c; Aiello et al., 2021a; Ligotti et al., 2021b; Martorana et al., 2014; Pellicanò et al., 2013; Rubino et al., 2019; Vasto et al., 2012a; 2012b). We report data related to a homogeneous population of Sicilian centenarians and nonagenarians (long-living individuals, LLIs) studied together with young people, adults, and older adults to have an adequate and matched number of controls. Data are summarized and discussed according to the available literature for their possible implication for the prevention and/or treatment of age-related diseases.

Epidemiological aspects of longevity in Sicily and LLIs life style

According to data from the National Institute of Statistics as of January 1, 2021, out of 59,257,566 people living in Italy, 17,156 are centenarians (2.90 centenarians/10,000). In Sicily there are 1,167 centenarians and total number of inhabitants is 4,840,876 (2.41 centenarians/10,000). Taking into account the increasing number of young Sicilian people emigrating over time, these values suggest that the Sicilian population is not experiencing a rate of longevity similar to other places in Italy (Istat, 2021).

On the other hand, a demographic survey performed in 2007 demonstrated that some very small municipalities located on unpolluted mountain areas of Sicily were characterized by a reduced mortality at the age of 80 and over. This implied an increase in number of centenarians in those zones (Bürkle et al., 2007). So, we focused our attention on one of these mountainous areas, the villages of the Sicani mountains. We performed an exhaustive nutritional assessment. The results showed that 12 years ago the centenarians of these very small villages followed a Mediterranean diet (MedDiet), with low glycaemic index and low animal protein intake. Their meals were frugal and three a day, composed by an abundant consumption of seasonal fruits and vegetables dressed with homemade extra virgin olive oil while small amounts of carbohydrates and meat intake was reported (Vasto et al., 2012a; 2012b).

More recently, we focused our attention on another of these mountainous areas, the small towns of the Madonie mountains (Accardi et al., 2019c). On the basis of ISTAT data, we identified seven towns and villages (Petralia Soprana and Sottana, Geraci Siculo, Bompietro, Castellana Sicula, Blufi, Isnello) that seemingly experienced high longevity (6 centenarians/14,055 inhabitants; 4.27 centenarians/10,000 as of January 1, 2021). An increase in the emigration of young people over time must be considered, thus we checked the death age of more than 37,374 newborns between 1881 and 1917 in these towns and villages. About 1,700 individuals died at the age of 90 years and over, 81 of which were centenarians. Therefore, the probability to reach 90 and 100 years old was of 4.47% and 0.22% respectively. These results cannot help us but conclude that these small towns exhibit an exceptional level of longevity as that observed in Sardinia (Poulain et al., 2004), and their populations are experiencing a higher longevity as compared to other places in Sicily and in Italy. It is very interestingly that in one of these villages, i.e., Isnello, there is the presence in its register of two supercentenarians (i.e., people who have reached the age of 110 years), a man and a woman, in which their ages have been validated, and of a third one whose age was not yet validated (Poulain, Busetta and Caruso, unpublished observations).

To gain insight to the epidemiological context, we compared the Standardized Mortality Ratio (SMR) of the Palermo province districts, including the municipalities of interest respect to Palermo city. The SMRs estimates reported for the districts were systematically lower than those reported for Palermo city. These mortality outcomes confirm that the Madonie municipalities belong to a zone with a high rate of longevity (Accardi et al., 2019c).

As discussed in the next paragraph, a nutritional assessment, performed 12 years later than the previously reported data, confirmed the possible association of longevity phenotype with a Mediterranean lifestyle, but not during extremely longevity (Aiello et al., 2021a).

Coming back to supercentenarians, it is noteworthy that in Sicily as of January 31, 2021, the oldest living male and female persons in Italy, according to the Italian supercentenarians database, were born in Sicily and have always lived there: the men (A.T.) at Caltabellotta (3,314 inhabitants) and the women at Piazza Armerina (20,886 inhabitants). It is intriguing that both places are mountainous areas, 949 meters the altitude of Caltabellotta, 695 meters above that of Piazza Armerina. Moreover, both lived in family settings (The Italian Supercentenarians Database, 2021).

Thus, in our Sicilian surveys (Accardi et al., 2019c; Aiello et al., 2021a; Vasto et al., 2012a), longevity concerns people living in small towns or villages quite far from the big cities (therefore, these settings are without pollution). A recent study conducted in the United States investigated the role of air pollution in the likelihood of achieving longevity measured as age 85 or older. In this nationwide analysis of approximately 28 million individuals ≥ 55 years of age in 3,034 counties, higher levels of particulate matter air pollution were associated with lower likelihood of longevity, even after adjusting for smoking, obesity, demographic variables, socioeconomic variables, total and age-specific migration rates and differences between the nine divisions of the United States Census (Baccarelli et al., 2016). In these Sicilian villages, then, LLIs in their life had working conditions different from those found in the big cities as well as different lifestyles, i.e., reduced smoking and alcohol abuse and MedDiet (presently or in the past). In fact, all LLIs are no smokers with a small percentage of former smokers (20%).

In addition, in these villages and small towns, people have greater access to family support and social networks. That determines better health care with lower levels of mortality, especially whether there are daughters. Accordingly, almost all the LLIs studied in these two surveys lived with their relatives. They live surrounded by family love in total serenity, away from stress and everyday worries, with an optimistic view of their life. Higher optimism was associated with increased likelihood of healthy ageing (James et al., 2019). Moreover, Lee et al. (2019) have demonstrated that people with highest versus lowest optimism levels had 1.5 (women) and 1.7 (men) times greater odds of surviving to age 85. It is relevant to our discussion that optimism is a potentially modifiable health asset; in fact, the feasibility and the positive impact of an optimism-promoting program among patients with heart disease in a randomized controlled trial has been demonstrated (Mohammadi et al., 2018). So, since lifestyles are promoted by family and social relationships, the familial and social network protects one against premature death.

Finally, almost all the LLIs studied in these two surveys lived in mountains, mostly in multi-storey houses, encouraging exercise throughout their lives. In this regard, there are some world zones, called blue zones (BZs), defined as a rather limited and homogenous geographical area where the population shares the same lifestyle and environment, and its longevity has been proved exceptionally high in these areas. Most LLIs of the BZs in Sardinia, Costa Rica, Ikaria and in the Italian region of Cilento, all rich in centenarians, live on the mountains (Poulain et al., 2013).

These populations have preserved a traditional lifestyle with an ideal social context as habitat, economic activity, intensive community, and family support for their oldest old, as well as the consumption of locally produced food. This has likely facilitated the accumulation of ideal conditions capable of limiting the factors that negatively affect health in the Western world (Poulain et al., 2013). The emergence of LLI phenotypes should be due to a balance between the benefits of traditional lifestyle and those of modernity, such as increases in wealth and medical care. Accordingly, the average high slope of the terrain, quite common in the mountain zone, should be responsible for a long life intense physical activity, hence improving the cardio-respiratory fitness of the inhabitants (Poulain et al., 2004).

This agrees with studies that support the positive association between increased levels of physical activity, exercise, and improved health in older people (Taylor, 2014). Physical activity, in fact, has a positive anti-aging impact at the cellular level, underlining its specific role in attenuating the effects of hallmarks of ageing (López-Otín et al., 2013) (Table 1.).

Table 1. Effects of physical activity on hallmarks of ageing in models and in human beings

References in: Accardi and Aiello, (2021).

Regular physical activity in the older population prevents or postpones several age-related pathologies such as sarcopenia or frailty, cardiorespiratory and metabolic diseases and cognitive decline. It is also involved in the decrease of blood pressure levels and in the improvement of metabolic function by the increase of muscle protein synthesis (Accardi and Aiello, 2021; Garatachea et al., 2015).

If older people are properly advised by family, friends, or doctors, they can be encouraged to increase their activities, keeping costs low and enjoyment high, facilitating group-based activities and increasing self-efficacy for exercise (McPhee et al., 2016).

Diet of Sicilian centenarians

Lifestyle represents one of the most relevant aspects in ageing research since it is an important modifiable factor that affects ageing processes. A healthy lifestyle can limit the damage caused by environmental influences. Among the lifestyle factors that may influence successful ageing and longevity, physical activity and healthy dietary habits have a great impact. Both can have systemic anti-aging effects, playing a significant role in determining the well-being of older people and in delaying and reducing the risk of onset of diseases. Indeed, they can act on all the hallmarks of ageing (Accardi and Aiello, 2021). In the previous chapter we briefly discussed the role of physical activity in the attainment of longevity in our LLIs, in the present chapter we will discuss the role of diet.

As for the LLI diet (Aiello et al., 2021a), it is a slow-ageing (Table 2.) anti-inflammatory diet because it is rich in bioactive foods such as fruit, vegetables, legumes and extra virgin olive oil and poor in red meat, although it is not closely adherent to the traditional MedDiet (Gambino et al., 2018; Leonardi et al., 2018; Vasto et al, 2014a). Concerning the other age groups, our results are in agreement with a survey performed on 3,090 Sicilians that assessed low to moderate adherence to the traditional dietary patterns among the inhabitants of Sicily, particularly in the younger segment of the population (Grosso et al., 2014).

In fact, following the economic boom, the diet of the populations of Southern Italy and the Italian islands has changed. The consumption of whole cereals and vegetables has decreased, while meat, fish, fats and sugar consumption has significantly increased. During this nutritional transition there was likely a change in the diet of the LLIs as in the rest of Italians (Teti, 2015). Thus, the LLIs under study adhered to the MedDiet at a young age for food shortage rather than choice. At that time, the food was strictly seasonal and composed by local products only rich in nutraceuticals, and the amount of food was sufficient not excessive, hence people experienced a kind of calorie restriction with a pro-longevity effect (Fontana et al., 2010). It is likely that these eating habits could affect an individual’s ability to achieve extreme longevity through epigenetic modifications (Puca et al., 2018).

Table 2. Overview of positive effects of slow-ageing diets on some parameters

Dietary restriction (DR), defined as dietary regimen in which specific food groups or micronutrients are reduced or removed from the diet, was first shown about 80 years ago to extend lifespan in rats. Most of these interventions provide a significant health-span increase also in humans. Caloric restriction, the reduction of total calories intake by 20-40% without malnutrition, is the most well-known DR to delay ageing in model organisms. In models, cycles of plant-based fasting mimicking diet (FMD) lasting 4 days, followed by a standard ad libitum diet, determined a decrease of blood glucose and IGF-1 levels compared to a control diet group. The results also demonstrated that FMD cycles can have profound effects on visceral fats and promote immune system rejuvenation. The Dietary Approaches to Stop Hypertension (DASH) diet is the main common prescribed diet to fight high blood pressure and was developed by the National Heart, Lung, and Blood Institute. It is a soft and balanced eating plan that helps the health of the heart, which reduces the risk of hypertension, one of the most common age-related phenotypes. Concerning plant-based diets, according to the United States Department of Agriculture, American Heart Association, and American Institute for Cancer Research, half of the daily rations should consist of vegetables and fruits to assure adequate intake of nutrients, fiber, and micronutrients. On the other hand, plant proteins have not been linked to an increase of IGF-1 levels but have been linked to lower blood pressure, improved insulin sensitivity, reduced low density lipoprotein (LDL) levels, and lower incidence of CVDs. Moreover, it was seen that rats fed by soy proteins have a higher lifespan than those fed by casein (Song et al. 2016). Asiatic diet it is characterized by relatively high consumption of unrefined, low glycaemic index sugars and proteins from vegetables, legumes and fruits, with moderate fish and marine food consumption. Mediterranean Diet (MedDiet) is treated in the text.

The table shows increase or decrease of the different parameters. These variations are the same for all the dietary patterns. All slow-ageing diets are responsible for a hypoactivation of insulin/IGF-1 pathway. All variations are statistically significant as reported by Aiello et al. (2019c).

Concerning slow-ageing diets (Aiello et al., 2019c), they are interventions that can slow the ageing process, delaying or preventing a range of chronic age-related diseases through the modulation of the relevant intracellular signalling pathways such as nutrient sensing pathways (see next chapter). Regarding anti-inflammatory diets, inflammatory status is sensitive to several environmental factors, among which diet ranks the most important determinant. The individual foods of the diet are able to act as pro-inflammatory stimuli. With the aim to quantify the impact of specific foods on the inflammatory profile of the subjects, so-called Dietary Inflammatory Index has been developed. Several studies have shown that diet is one of the most effective regulators of inflammatory processes by identifying specific pro-inflammatory and anti-inflammatory dietary habits associated with different pathologies or their treatment (Falzone et al., 2019; Leonardi et al., 2018; Shivappa et al., 2014).

Furthermore, a significant increase in body mass index (BMI) in all groups was observed with aging, with the significant exception of centenarians. Interestingly, the BMI values of centenarians are significantly lower than the values observed in older people (Aiello et al., 2021a). These data are interesting considering that underweight and overweight conditions are unfavourable for longevity. Accumulation of fat in LLIs is likely to protect against death. This is the so-called obesity paradox which implies an inverse correlation between BMI and mortality. However, it should be emphasized that this data could instead be correlated to a low specificity of the BMI for this segment of the population (Kouvary et al., 2019; Puzianowska-Kuznicka et al., 2019).

As pointed out by Caruso and Candore (2021), the optimal diet model for promoting successful ageing and longevity and health is the one capable of satisfying at least the points reported considering data from centenarian studies, and all accompanied by an optimal modulation of the light-dark cycle and adequate quality and quantity of sleep. Sicilian centenarians as well as the other Mediterranean centenarians had the following common denominators: high intake of fruit, legumes and vegetables, outdoor movement, less calorific intake than current recommendations suggest, prevalence of local products and gastronomy, and correct circadian distribution of meals, which includes a hearty breakfast, light snacks and frugal dinner (Vasto et al., 2012; 2014a; 2014b; Franceschi et al, 2018). For successful ageing, the diet must guarantee over time the quality of the food introduced, inspired by the food choices typical of the Mediterranean model with oriental influences. People must adopt a calorie intake that, depending on the proposed diet, provides a quantity of calories that is around 15-20% the basal metabolic rate in subjects with a low level of physical activity. Significant effects of calorie restriction (10-15% lower than the basal metabolism) are demonstrated even in humans. Adopting a balanced diet with that caloric intake is considered effective and safe, but must provide a protein content of around 0.95-1 g/kg body weight. For older people, slightly lower amounts are indicated and animal proteins should be limited. Both a low-calorie diet and the regular use of nutraceutical compounds (see below) could be the nutritional basis for successful ageing and longevity, together with all the other measures that characterize an appropriate lifestyle (Aiello et al., 2019b; Rickman et al., 2011).

A particular aspect of diet concerns some compounds principally contained in fruit and vegetables, i.e., nutraceuticals. This term is a portmanteau word, a combination of nutrition and pharmaceutical and refers to naturally derived bioactive compounds that are found in foods, dietary supplements and herbal products, and have health promoting, disease preventing, and/or medicinal properties. Several nutraceuticals exhibit anti-aging features by acting on the inflammatory status and on the prevention of oxidative reactions. They have been suggested to result in a significant reduction of all risk factors for age-related diseases, enhancing the attainment of successful ageing (Aiello et al., 2016; 2020).

Thus, there is a compelling body of evidence indicating that adherence to healthy dietary patterns and intake of plant-derived bioactive compounds may serve as potential strategy to preserve body function, slowing the progression of ageing and reducing the incidence of age-related disease, i.e., an approach called nutrigerontology (Aiello et al., 2016). The effects of healthy diets on the hallmarks of ageing and their putative mechanisms are treated by Accardi and Aiello (2021).

Molecular aspects of Sicilian centenarians

There are only two genes whose variants have been consistently associated with longevity. They are Forkhead box O3A (FOXO3A) and Apolipoprotein E (APOE) (Ferrario and Puca, 2017; Puca et al., 2019; Villa et al., 2019).

FOXO3A acts as a transcription factor for several homeostatic genes in response to the reduced signalling of the insulin/IGF-1 pathway, thereby increasing lifespan. The activation of this pathway by a diet rich in proteins and refined sugars suppresses its transcription. Several model studies have shown that genetic changes impact these signals increasing the activity of FOXO3A through the modulation of its interconnections with upstream and downstream molecular partners (Aiello et al., 2016; 2017; Di Bona et al., 2014). The rs2802292 single nucleotide polymorphism (SNP) G allele of FOXO3A was shown to be associated with longevity, particularly in males, in a meta-analysis of over 7,900 cases and 9,500 controls (Revelas et al., 2018). However, in Sicilian LLIs, we did not observe an association with longevity, likely for the small sample size, although, another possibility refers to a failure of the selection of allele in the Sicilian population because the diet rich in vegetables and fruits and poor in refined sugars, is responsible for a hypoactivation of insulin/IGF-1 pathway (Aiello et al., 2019c; 2021a). That points out the role of slow-ageing diets previously stated, as well as nutraceuticals contained in them, in the transcription of homeostatic genes involved in survival and longevity. For an exhaustive discussion of nutrient sensing pathways see Aiello et al., (2017; 2020), Caruso et al., (2021a), and Vasto et al., (2014a).

APOE plays a central role in the metabolism of plasma lipoproteins and the transport of lipids within a tissue. Furthermore, it is the main carrier of cholesterol in the brain. The genetic polymorphisms of APOE are determined by three alleles, ε2, ε3 and ε4, which are defined by combinations of genotypes of SNPs rs7412 and rs429358. The products of the three alleles differ in different functional properties. APOEε2 shows fluctuations in its frequency in the various populations with no apparent trend, whereas APOEε3 is the most frequent allele. APOε4 is a pro-inflammatory allele (associated with AD and, to a lesser extent, CVDs) and is linked to increased blood cholesterol, i.e., a thrifty gene. It is considered the ancestral allele because it conferred a selective advantage in the hunter/gatherer societies, an advantage that has disappeared in the modern world (Accardi et al., 2019b; Corbo and Scacchi, 1999). Sebastiani et al., (2019) assembled data from seven longevity studies for a total of 28,297 participants showing that APOEε4 is associated with decreased probability of longevity, whereas the genotypes ε2/ε2 or ε2/ε3 are associated with significantly greater likelihood of longevity. In our LLIs, we did not observe an association of Apoeε2 with longevity, but we found the lowest percentage of APOε4 (Aiello et al., 2021a). These results are consistent with a recent analysis that shows that in South Italy populations there is a weaker protective effect of APOε2 (Gurinovich et al., 2019). The reduced frequency of the pro-inflammatory allele APOEε4 underscores the role of control of inflammation in the achievement of longevity.

One common denominator of ageing is the accumulation of genetic damage throughout life. Accumulation of DNA damage with age appears to affect the genome near-to-randomly (with consequent genomic instability), but there are some chromosomal regions, such as telomeres, that are particularly susceptible to age-related deterioration (López-Otín et al., 2013). Telomeres are repetitive sequences of DNA at the ends of chromosomes that undergo shortening with each mitotic division. This process is modulated by inflammation and oxidative stress. Short telomeres therefore represent a marker of cumulative burden of inflammation and oxidative stress. Many data have demonstrated the association between age-related diseases and short telomeres, whereas centenarians show longer telomeres than unsuccessfully aged older people. Indeed, a healthy lifestyle is linked to longer telomeres, whereas shorter telomeres have been shown to be associated with a higher risk of all-cause mortality (Accardi and Aiello, 2021; Davinelli and De Vivo, 2019). Accordingly, in our Sicilian sample, female LLIs have telomere length not significantly different from that of older female adults (Aiello et al., 2021a). Furthermore, the telomere length of two semi super- and super-centenarian sisters have been shown to fit in the average plus/minus standard deviation of 60-69 Sicilian women (Accardi et al., 2020).

Negative factors associated with telomere length are represented by high BMI, cigarette smoking, chronic stress, psychological disorders and early childhood adversity. Positive factors include healthy lifestyle choices, physical activity, antioxidant foods, MedDiet and meditation. Virtually all of these factors act respectively by stimulating and attenuating the inflammatory state and oxidative stress (Davinelli and De Vivo, 2019). Therefore, trying on the one hand to eliminate the negative factors and on the other hand to increase the positive factors could play a role in achieving longevity through the maintenance of telomeres, as suggested by the findings obtained from our centenarians (Accardi et al., 2019c; 2020; Aiello et al., 2021a).

In recent years, metformin, a widely used hypoglycaemic drug, has attracted growing attention in the field of anti-aging research. Recently, metformin has been demonstrated to prevent placental telomere attrition. Moreover, patients with diabetes mellitus treated with metformin demonstrated significantly longer telomeres than those in the control group. Metformin seems to play this role by activating telomerase; in the meantime, by increasing gene expression of sirt-1 should be able to promote genomic stability (Hu et al., 2021).

Immunophenotypes of Sicilian LLIs

As we age, our immune systems steadily decline, becoming less efficient in eliminating pathogens, cancer cells, senescent cells, infectious diseases, vaccines and age-related inflammatory diseases. As the immune system performs this myriad of functions with a multitude of specialized cell types, its decline has serious ramifications for health and longevity.

This phenomenon, called immunosenescence, affects all the aspects of immunity, although T lymphocytes are dramatically affected. In fact, ageing processes more extensively affect acquired immunity than innate immunity. Several factors, such as genetics, nutrition, exercise, biological and cultural sex, and previous exposure to microorganisms, in particular human cytomegalovirus (HCMV), can influence immunosenescence (Alello et al., 2019b; Caruso and Vasto, 2016; Moskalev et al., 2020).

Age-associated immune changes have been extensively reported. The most important alterations are represented by the reduction in the number of peripheral blood naïve cells, i.e., cells that have not encountered their cognate antigens, with a relative increase in the frequency of antigen-specific memory cells. These two alterations, together with inflammageing, which will be covered in the next chapter, are considered the hallmarks of immunosenescence (Aiello et al., 2019b; Caruso and Vasto, 2016).

As discussed in Accardi et al., (2019b), centenarians show a complex and heterogeneous phenotype, which seems to be the result of the capacity to adapt and remodel their body in response to stressors. Therefore, they become able to escape or delay the major age-related diseases. Of interest, their immune system shares characteristics both of older and younger people. B and T cell number and function are similar to those observed in older people (however, T cells may show a light increasing trend when compared to older people), whereas number and function of NK cells (particularly, NK CD56dimCD16+ characterized by increased cytotoxicity) are well conserved and comparable to those observed in younger people. This supports the hypothesis that a well-preserved cytotoxic activity of NK cells may represent a biomarker of healthy ageing and longevity (Aiello et al., 2019b; Ligotti et al., 2021b).

However, although centenarians are considered the best example of successful ageing, to gain insight into mechanisms of immunosenescence and its clinical relevance, a further and maybe better model is represented by their offspring (and supercentenarians, see below). Centenarian offspring (CO), who are typically in their 70s and 80s, have a survival advantage when compared to age-matched controls whose parents died at an average life expectancy. CO, like their centenarian parent(s), have genetic and functional advantages associated with lower CVD risk (Aiello et al., 2019a). These findings support the hypothesis that centenarian offspring are predisposed to healthy ageing and longer survival, making them a suitable target of immunological studies, because, unlike centenarians, they have an appropriate control group, important for this type of study, i.e., older people without centenarian parents. A further complication derived from the studies of centenarians is their extremely variable clinical conditions. Indeed, among them, there are frail individuals with multiple pathologies, as well as healthy centenarian subjects who lack cognitive disorders, although some of them show signs of the advanced ageing process. In addition, their acquired immune system has been subjected to a pathogenic burden for decades of years not predicted by evolution (Accardi et al., 2019a; 2019b; Aiello et al., 2019b). So, in these last twelve years we have performed several studies on B and T immunophenotype profile of Sicilian CO.

The B-cell compartments of CO have shown a reduction in B cell count, as shown in older people. However, they do not show the typical shift from naïve to memory cells, as previously stated to be observed in their age-matched controls (Colonna-Romano et al., 2010; Buffa et al., 2013; Martorana et al., 2014). Indeed, CO do not show both an increase of the late-memory double negative B cells (IgD-CD27-) and a reduction of B naïve cells (IgD+ CD27-) observed in the average older population. Thus, their B cell compartment looks similar to that of younger people (Colonna-Romano et al., 2010). It was also observed that the late memory B population (CD19+CD38-CD24-) is not increased in CO (Buffa et al., 2013). In addition, their IgM serum levels show values similar to those observed in younger subjects (Colonna-Romano et al., 2010). Thus, CO do not have the typical trend of memory/naïve B cell subsets observed in older people and this agrees with the higher levels of IgM, the antibody of primary humoral response, in their serum when compared with data obtained in age-matched controls (Bulati et al., 2018).

Another variability factor involved in the outcome of immunosenescence is represented by chronic viral infections. HCMV infection may influence the T cell subset distribution, leading to both reduction of naïve (CD45RA+CCR7+CD27+CD28+) CD8+ T cells and to increase of late differentiated effector-memory (TEM, CD8+CD45RA-CCR7-CD27-CD28-) and terminally differentiated effector-memory T cells re-expressing the naïve-cell marker CD45RA (TEMRA, CD8+CD45RA+CCR7-CD27-CD28-) (Aiello et al., 2019b). Although these naïve-memory shifts considered typical of immunosenescence in older people, HCMV-seropositive offspring of long-lived people do not show the age-associated decrease of naïve T cells. Furthermore, memory T cell subsets do not increase in offspring of long-lived families, differently from that observed in age-matched controls (Bulati et al., 2018).

It has also been demonstrated that, when compared to their HCMV-infected age-matched controls, HCMV-seropositive CO have reduced levels of CD8+ T cells expressing CD57 and KLRG1, sometimes referred as marker of replicative senescence (Pellicanò et al., 2014).

More recently (Rubino et al., 2019), the values of other T cell subsets, in particular regulatory T cells and senescent T cells, have been evaluated in CO of Sicilian ancestry, comparing their values to that of control cohorts. This study confirms and extends previous results showing that CO retain more youthful immunological parameters and that the exhaustion of their immune system is less evident than in the elderly without centenarian parents.

Thus, while CO lymphocyte compartments do not show the typical feature of immune system ageing, i.e., the shift from naïve to exhausted memory cells, they do present a younger immune profile. This reservoir of naïve B and T cells might play a relevant role in making CO able to keep fighting off new infections, hence prolonging their life (Aiello et al., 2019a; Bulati et al., 2018).

The overview on lymphocyte age-related modification in CO compared to older people without centenarian parents is given in Table 3.

Table 3. B and T lymphocyte age-related