Molecular Hydrogen for Medicine: The Art of Ancient Life Revived

By Yuh Fukai

This book provides a comprehensive account of the current status of molecular hydrogen medicine, a young field that emerged with the discovery that inhalation of hydrogen gas leads to the elimination of harmful reactive oxygen species in rats. Various physiologic effects have since been demonstrated, and possible medical applications identified. Numerous clinical projects have now been undertaken, yielding startling results. Despite this, molecular hydrogen medicine remains underappreciated among the medical community at large. The author aims to rectify this situation by fairly but critically evaluating the potential clinical benefits based on the latest scientific research. In addition, the observed physiological effects of hydrogen gas are considered within the broad context of the evolution of life on earth, offering new perspectives and helping to place molecular hydrogen medicine legitimately within the framework of life sciences. Written in an accessible manner, the book will be of value to students, researchers, clinicians, and the general public.

• Language: English
• Publisher: Springer
• Release date: Nov 25, 2020
• ISBN: 9789811571572

Book preview

Part I

What is Molecular Hydrogen Medicine?

A consistent description is given of Molecular Hydrogen Medicine, from its birth in 2007 to the present state and its future prospect, encompassing animal experiments and numerous clinical applications. Out of vast number of research papers on various physiological and therapeutic effects of molecular hydrogen, a limited number of well-qualified papers including animal experiments and clinical trials have been selected and elucidated. A brief description is given of the mechanisms of action presently under intensive studies. Some fundamental properties of molecular hydrogen (hydrogen gas and hydrogen water) are explained, together with its preparation, handling and methods of administration to provide basic information necessary for Molecular Hydrogen Medicine.

Application of heavy water for organ transplantation, though slightly out of context, is included as a recent topic in the Hydrogen Medicine.

Key players of Molecular Hydrogen Medicine are hydrogen gas and hydrogen water. Hydrogen water is simply water in which hydrogen gas has been dissolved, in other words, a mixture of hydrogen molecules and water molecules. As hydrogen water has been found to exhibit nearly the same effects as hydrogen gas, the actual effective component is thought to be the hydrogen molecule.

Usually, molecular hydrogen is so stable that it does not undergo any chemical reaction with any substance at room temperature and is therefore regarded to be an inert gas for living bodies. Molecular Hydrogen Medicine is peculiar in that, in contradistinction to this common sense of biochemistry, it aims to investigate physiological effects exerted by molecular hydrogen and its possible clinical applications. This is a new field of research having profound implications for life science.

© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2020

Y. FukaiMolecular Hydrogen for Medicine https://doi.org/10.1007/978-981-15-7157-2_1

1. The Power of Hydrogen Molecules Uncovered

Yuh Fukai¹  

(1)

Department of Physics, Prof. Emer. of Chuo University, Tokyo, Japan

Abstract

After some sporadic reports, a seminal paper of Ohsawa et al. (Nat. Med. 13:688–694, 2007) was published that clearly demonstrated physiological and therapeutic effects of molecular hydrogen (MH), and opened a new area of medicine to be called Molecular Hydrogen Medicine (MHM).

1.1 Early Sporadic Reports of Hydrogen Effects

In the experiment of Malcolm Dole et al. (1975), mice with skin cancer (squamous cell carcinomas) were reared in an environment with 0.8 MPa (8 atm) of hydrogen gas (and an appropriate amount of oxygen) for 2 weeks, which led to the shrinkage of the cancer cells. This was an important discovery demonstrating the physiological effects of molecular hydrogen, but attracted little attention at that time, and no follow-up experiments were carried out.

The next time the physiological effects of hydrogen gas appeared in print was 20 years later in an article titled Gas Therapy in the Daedalus column of Nature Magazine (Jones 1996). This article suggested that inhalation of hydrogen gas could rapidly eliminate hydroxyl radicals within the body, and that hydrogen should be entirely harmless to the body and be completely excreted without being accumulated, and therefore should be an ideal gas therapy. The article stated that hydrogen could also be dissolved in water and taken orally. This might appear to be an excellent prediction, but in fact, Jones apparently wrote the article as a fantasy. Daedalus appears in Greek mythology as an inventor who made wings for his son, Icarus, and the column was named after him because it was science fiction.

Subsequently, Gharib et al. (2001) attempted to test Jones’ fantasy in real life. They reared mice with chronic liver tumors in an environment with an additional 0.7 MPa of hydrogen gas (of a total of 0.8 MPa) for two weeks and discovered that the liver damage in these mice was markedly reduced. Jones and Gharib unknowingly rediscovered the pioneering research of Dole et al. (1975). However, this rediscovery, too, was forgotten, having failed to attract any attention.

In fact, prior to these sporadic reports, a company called COMEX (Marseille, France) had started intensive studies to utilize hydrogen for deep sea diving technologies. After performing various experiments on cells and animals, they succeeded in developing a high-pressure mixture gas containing hydrogen which is effective for the prevention of diving disease. This may be regarded to be the very first achievement related to Molecular Hydrogen Medicine.

1.1.1 How the Story Started in Japan

Hydrogen research in Japan started in an entirely different way. In Japan, there were people, including physicians, who worked fervently to emphasize the health benefits of reduced water produced by the electrolysis of normal water. Reading early publications on the subject, one can see numerous examples of its benefits. The effects mentioned include improved fitness, smoother skin, improved diabetes symptoms, and anti-cancer effects. In all the cases, however, there was a lack of stringency required for scientific research, and therefore, these reports cannot be taken at face value. Nonetheless, some of the data generated cannot be completely dismissed. For example, MiZ Co., Ltd. reported that electrolyzed water suppressed oxidative liver damage (Yanagihara et al. 2005).

Having observed the controversy in this research field continuing for years, the research group of Shigeo Ohta and Ikuroh Ohsawa of the Nippon Medical School decided to intervene. As experts in biochemical and cellular mitochondrial physiology they were determined to settle the issue of this miracle water through cautiously designed experiments.

1.2 Ohsawa, Ohta, and the Dawn of Molecular Hydrogen Medicine

Ohta had been studying the functions of mitochondria for more than thirty years. However, with growing awareness of the harmful effects of reactive oxygen species (ROS) generated by mitochondria, including aging and various diseases, Ohta came to focus his attention on these effects. In 2005 Ohta’s research group began investigating the effect of hydrogen on ROS. As a standard procedure in biochemical research, they started from the cellular level and moved to the organs, and then to the whole body. They started with animal experiments, aiming to progress to clinical applications. In this section, I introduce their research which paved the way for Molecular Hydrogen Medicine.

1.2.1 Molecular Hydrogen Selectively Eliminates ROS

Not long after starting their cellular experiments, the Ohta group were surprised by the remarkable effects of hydrogen. Later, Ohta wrote the following:

Soon after we started, we were shocked by what we saw. The first results were such a surprise that I stopped in my tracks. It was the third day of the experiment and, without thinking, I yelled: Look! It’s amazing! In the culture media with hydrogen, ROS induced in cells didn’t do any harm. The cells were all alive. It was a revolutionary discovery…

This was the first experiment that demonstrated the effects of hydrogen on living cells. Stimulating the formation of ROS in cells using drugs usually causes the cells to shrink and become spherical in shape as their metabolism deteriorates, and they eventually die. However, when hydrogen was dissolved in the culture medium, the cells’ functions were unaffected and cell death was greatly reduced (Fig. 1.1). Microscopic observations showed that hydrogen could enter all organelles within the cell (nucleus, cytoplasm, mitochondria, etc.), in contrast to traditional antioxidants which are unable to enter the cell. Their subsequent experiments led to another important discovery that the effect of hydrogen was very selective (Ohsawa et al. 2007). As shown in Fig. 1.2, the scavenging effect of molecular hydrogen in solution was different for different ROS; particularly large for •OH, much smaller for ONOO–, and negligibly small for other ROS. This implies that molecular H2 eliminates only harmful ROS, leaving other ROS playing important roles in cell signaling intact. This is a completely different behavior from existing antioxidants (e.g., vitamin C), which eliminate both beneficial and harmful ROS indiscriminately.

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Fig. 1.1

Molecular hydrogen H2 protects PC12 cells from reactive oxygen species (hydroxyl radicals •OH). Number of cells 1 h after induction of •OH; in culture medium without H2 (left), and with H2 (right) (I. Ohsawa 2007, private communication)

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Fig. 1.2

Molecular H2 dissolved in saline scavenges •OH selectively in cell free system. (a) Formation of •OH by Fenton reaction at 0.8 mM H2; Baseline 1, without H2O2, and Baseline 2, without ferrous perchlorate. (b) ~ (f) levels of ROS concentrations after incubation with 0.6 mM of H2: (b) •OH, (c) ONOO−, (d) O2−•, (e) H2O2, (f) NO−•. Mean value ± SD, (n = 6). P < 0.05 (Ohsawa et al. 2007)

The antioxidant effects of molecular H2 were also confirmed by other in vitro experiments. Figure 1.3 shows that the increase of 8-OHdG (8-hydroxy-2′-deoxyguanosine) and 4-HNE (4-hydroxyl-2-nonenal) produced by peroxidation of DNA and lipids, respectively, was suppressed effectively by molecular H2. These discoveries strongly suggested that hydrogen should have the potential to act as a new antioxidant.

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Fig. 1.3

Molecular H2 protects cultured PC12 cells by scavenging •OH radicals. Suppression by molecular H2 of oxidation (induced by antimycin A) of nuclear DNA measured by 8-OHdG (P < 0.05) and peroxidation of lipids measured by 4-HNE conjugate (P < 0.01). Mean ± SD (Ohsawa et al. 2007)

Then, with clinical applications in mind, they proceeded to investigate the effects of hydrogen in ischemia-reperfusion (I-R) injury, in which serious oxidative damage usually occurs. I-R injury occurs in circumstances such as organ transplant, where blood (with oxygen) is temporarily removed from an organ and subsequently poured into the organ again (reperfused) after the transplant. Supplying oxygen after a period of oxygen deprivation results in the production of large quantities of ROS. This is a serious problem because the ROS can then cause damage in internal organs.

In their experiment, the cerebral arteries of rats were blocked to stop blood flow for 90 min, and the effect of hydrogen on brain damage upon reperfusion after 30 min was investigated. The results were eye opening. By having the rats breathe 2–4% H2 gas, the region of the brain damaged after1 day was reduced to nearly half (Fig. 1.4). Additionally, reductions in body temperature, body weight, and motor function as a result of I-R tended to recover after 1 week of hydrogen treatment. Thus, inhalation of H2 gas suppressed temporary brain damage due to I-R, as well as the associated secondary diseases. These experiments demonstrated, beyond any doubt, that H2 molecules administered as a gas or dissolved in water passed through tissues and biological membranes and eliminated hydroxyl radicals throughout the body, the most harmful ROS.

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Fig. 1.4

Brain injury by ischemia/reperfusion in rats was reduced by inhalation of H2 gas. The infarct size 1 day after the I-R (white area) was reduced by inhalation of 2% H2 gas during reperfusion (Ohsawa et al. 2007)

Subsequently, their group demonstrated by experiments with mice that hepatic I-R injury could be suppressed by inhalation of H2 gas (Fukuda et al. 2007). The procedure was as follows: occlusion for 90 min, reperfusion for 180 min, and inhalation of H2 gas (1–4%) for the last 190 min. Figure 1.5(a) shows that the vacuolization induced by hepatic injury was suppressed effectively by H2 gas, whereas He gas exerted no effects. Figure 1.5(b) shows that the inhalation of H2 gas reduced the level of MDA (malondialdehyde), a marker of oxidative stress, to almost normal level (without I-R treatment), and in Fig. 1.5(c) are shown the concomitant changes of serum ALT (alanine aminotransferase), a biomarker of hepatic injury. The effect of molecular H2 was very similar.

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Fig. 1.5

Molecular H2 suppresses hepatic injury in mice. Effects of molecular H2 on (a) vacuolization in hepatic tissues (n = 6, *P < 0.001), (b) oxidative stress marker MDA (n = 6, **P < 0.0001), and (c) a marker of hepatic injury, serum ALT (n = 6, *P < 0.05, **P < 0.005) (Fukuda et al. 2007)

These experiments came as a big surprise to most biochemists, because, due to its high chemical stability, H2 gas had been regarded as an inert gas to living bodies, including humans. However, as their experiments were so well designed and carefully performed that there was no room for any doubt in the result. And indeed, their results were confirmed by numerous follow-up experiments.

Thus, the seminal paper of Ohsawa et al. (2007) entitled Hydrogen acts as a therapeutic antioxidant by selectively reducing cytotoxic oxygen radicals attracted widespread attention, and research into possible clinical applications of hydrogen, now called Molecular Hydrogen Medicine, commenced.

Column 1: When Hydrogen Has Come to be Known—the World as Seen by Lavoisier

The word hydrogen means literally the element of water, which in fact consists of hydrogen and oxygen. This fact is now widely known, but was not known until the end of the eighteenth century when the French chemist Antoine Lavoisier conducted experiments to confirm for the first time that hydrogen is present in nature as an element and named it hydrogène (Fig. 1.6).

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Fig. 1.6

Lavoisier is the father of ‘hydrogène’. In his monumental work, Traité Élémentaire de Chimie, published in 1789, he gave this name to a gaseous substance that produced water when combined with oxygen, a composite of Greek hydro (water) and gene (make)

Lavoisier’s discovery conflicted with the phlogiston theory that predominated the academic community of the time, and more than 20 years passed before it was accepted as such. In the phlogiston theory, all flammable substances contain weightless and invisible phlogiston, and upon combustion, phlogiston leaves the substance and incombustible ash remains. In 1766, Henry Cavendish (UK) discovered a flammable gas that was lighter than air and suggested that it was phlogiston. This flammable gas (later known as hydrogen), and living gas (oxygen) comprising 1/5th of air reacted to produce water; thus, water was considered a living gas (oxygen) attached with phlogiston. Cavendish did not realize that the flammable gas was an element, being obsessed with the abstract notion of phlogiston at that time.

In contrast, Lavoisier adhered to concrete evidence. In the introduction of Lavoisier’s masterpiece "Traite Élémentaire de Chimie (Elementary Treatise on Chemistry) published in 1789, he stated: We only need to progress from learning what is known to what is unknown. The strict rule that I follow is never to form any conclusions which are not fully warranted by experiment, nor to provide any additional information in the absence of facts (Lavoisier 1743-1794" by Grimaux, Paris 1888).

Thus, from the results of his extensive experiments, knowledge that had not been predicted until then was gained, specifically that mass remains unchanged by chemical reactions.

In experiments with water, Lavoisier observed that steam flow on red-hot iron powder increased the weight of iron and led to the production of a lighter gas. He considered that this weight gain of iron was equivalent to the weight of oxygen in the air and concluded that water contains 85% oxygen and 15% hydrogen (light gas) by weight. Conversely, after mixing oxygen and hydrogen at a volume ratio of 1:2 (weight ratio of 84:16), he demonstrated that igniting the mixture produced water. According to our current knowledge of water, the volume ratio of oxygen to hydrogen is 1:2 and the weight ratio is 8:1. Given the difficulty of measuring the weight of light gases such as hydrogen, Lavoisier’s experiments were highly accurate. It was from these studies that hydrogen was firmly characterized as an element.

Lavoisier’s contribution to the understanding of combustion proceeded still further. He showed that when charcoal was combusted, it reacted with oxygen and produced a gas, which is now identified as carbon dioxide (CO2). Furthermore, he noted that in the gas exhaled by humans, oxygen was lost, and CO2 was generated. These observations led him to conclude that respiration was a slowly occurring combustion process. This finding was further advanced by the later invention of the calorimeter, which was used to establish relationships among and between movement, heat, respiration, perspiration, and digestion. These discoveries launched a new research field of physiology.

Years later, Lavoisier wrote a short comment on his unfinished studies on the chemistry of plants and animals. He stated that plants extract substances necessary for forming living organisms from the atmosphere and water, from the mineral kingdom generally speaking. Animals sustain their bodies by eating plants or animals that eat plants. Therefore, substances that are formed in animals are originally derived from the air and the mineral kingdom. Finally, fermentation, putrefaction, and combustion return the elements borrowed by animals and plants to the mineral kingdom. In what way does nature govern this wonderful cycle between these three kingdoms? How does nature construct combustible, fermentable, and perishable substances from materials that do not have such properties? As of now, this is an unfathomable mystery. However, combustion and putrefaction are certainly the methods to return materials forming plants and animals to the mineral kingdom. Thus, the constitution of substances as plants and animals must be the opposite phenomenon of combustion and putrefaction.

Modern chemistry, which was initiated by Lavoisier, has greatly developed since then. Subsequently, biochemistry, which examines the structures and reactions of diverse biological substances that support life activities, has become a colossal field and is continuing to advance.

Figure 1.7 shows a portrait of Antoine Laurent Lavoisier exhibited at the Conciergerie in Paris, where he was imprisoned at the time of French Revolution. Lavoisier was then subjected to a revolutionary trial for his participation in tax collection, and sentenced to capital punishment and guillotined on May 8, 1794. He was 50 years old at the time of death. His friend, a mathematician Joseph-Louis Lagrange, stated: It took them only an instant to cut off his head, but one hundred years might not suffice to reproduce its like. Although Lavoisier’s death was premature, so were the deaths of many others at that time, and as many as 2 million unnamed people shed blood as compensation for social transformation.

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Fig. 1.7

Antoine Laurent Lavoisier (1743–1794). A picture taken of the portrait displayed in Conciergerie, where he had been imprisoned before sent to the guillotine

References

M. Dole, F.R. Wilson, W.P. Fife, Hyperbaric hydrogen therapy: A possible treatment for cancer. Science 190, 152–154 (1975)Crossref

K. Fukuda, S. Asoh, M. Ishikawa, Y. Yamamoto, I. Ohsawa, S. Ohta, Inhalation of hydrogen gas suppresses hepatic injury caused by ischemia/reperfusion through reducing oxidative stress. Biochem. Biophys. Res. Commun. 361, 670–674 (2007)Crossref

B. Gharib, S. Hanna, O.M.S. Abdallahi, H. Lepidi, B. Gardette, M. de Reggi, Anti-inflammatory properties of molecular hydrogen: investigation on parasite-induced liver inflammation. Compte Rendu des Académie des Sciences, Life Sci 324, 719–724 (2001)

É. Grimaux, Lavoisier 1743-1794 (Paris, 1888)

D. Jones, Gas therapy. Nature 383, 676 (1996)Crossref

A.L. Lavoisier, Traité Élémentaire de Chimie (Paris, 1789)

I. Ohsawa, M. Ishikawa, K. Takahashi, M. Watanabe, K. Nishimaki, K. Yamagata, K. Katsura, Y. Katayama, S. Asoh, S. Ohta, Hydrogen acts as a therapeutic antioxidant by selectively reducing cytotoxic oxygen radicals. Nat. Med. 13, 688–694 (2007)Crossref

T. Yanagihara, K. Arai, K. Miyamae, B.