Hydrogen, a Novel Therapeutic Molecule, Regulates Oxidative Stress, Inflammation, and Apoptosis

Development of an aminoguanidine hybrid hydrogel composites with hydrogen and oxygen supplying performance to boost infected diabetic wound healing

Diabetic wounds tend to develop into non-healing wounds associated with a complex inflammatory microenvironment of uncontrollable bacterial infection, reactive oxygen species (ROS) accumulation, and chronic hypoxia. This study developed a multifunctional hydrogel system by integrating aminoguanidine and hydrogen and oxygen gas-release nanoparticles (PAP NPs) into phenylboronic acid-modified quaternized chitosan and an oxidized dextran network. Hollow mesoporous Prussian blue (HPB) nanozymes with superoxide dismutase- and catalase-like activities are promising bioreactors for simultaneously alleviating ROS accumulation and hypoxia by converting elevated endogenous hydrogen peroxide (H2O2) into oxygen in diabetic wounds. Simultaneously, incorporating ammonia borane (AB)-loaded HPB NPs served as a source of hydrogen, further reducing ROS overproduction and modulating pro-inflammatory cytokine responses. Aminoguanidine in the hydrogel network inhibits the formation of advanced glycation end products (AGEs), inhibiting skin cell apoptosis and promoting their proliferation and migration. Moreover, the hydrogel exhibited significant mechanical characteristics and self-healing capacity owing to the Schiff base and phenylboronate ester linkages. Incorporating PAP NPs into the hydrogel produced an exceptional photothermal response, effectively eradicating bacteria with a mortality rate exceeding 95 % within 10 min and protecting the wound from potential infections. In vivo studies demonstrated that PAP@Gel significantly accelerated the healing of infected diabetic wounds by mitigating oxidative stress, enhancing oxygenation, inhibiting inflammation and AGE formation, and reversing bacterial infections. This study highlights a promising nanomedicine approach for designing future diabetic wound dressings, providing a novel strategy for catalytic ROS scavenging and synergistic hydrogen and oxygen therapies.

Potential therapeutic applications of medical gases in cancer treatment

Medical gases were primarily used for respiratory therapy and anesthesia, which showed promising potential in the cancer therapy. Several physiological and pathological processes were affected by the key gases, such as oxygen, carbon dioxide, nitric oxide, hydrogen sulfide, and carbon monoxide. Oxygen targets shrinking the tumor via hyperbaric oxygen therapy, and once combined with radiation therapy it enhances its effect. Nitric oxide has both anti- and pro-tumor effects depending on its level; at high doses, it triggers cell death while at low doses it supports cancer growth. The same concept is applied to hydrogen sulfide which promotes cancer growth by enhancing mitochondrial bioenergetics and supporting angiogenesis at low concentrations, while at high concentrations it induces cancer cell death while sparing normal cells. Furthermore, carbon dioxide helps induce apoptosis and improve oxygenation for cancer treatments by increasing the release of oxygen from hemoglobin. Moreover, high-dose carbon monoxide gas therapy has demonstrated significant tumor reductions in vivo and is supported by nanomedicine and specialized medicines to boost its delivery to tumor cells and the availability of hydrogen peroxide. Despite the promising potentials of these gases, several challenges remain. Gas concentrations should be regulated to balance pro-tumor and anti-tumor effects for gases such as nitric oxide and hydrogen sulfide. Furthermore, effective delivery systems, such as nanoparticles, should be developed for targeted therapy.

Molecular Hydrogen Therapy: Mechanisms, Delivery Methods, Preventive, and Therapeutic Application

Molecular hydrogen (H2), recognized as the smallest gas molecule, is capable of permeating cellular membranes and diffusing throughout the body. Due to its high bioavailability, H2 is considered a therapeutic gas for the treatment of various diseases. The therapeutic efficacy of hydrogen is contingent upon factors such as the administration method, duration of contact with diseased tissue, and concentration at targeted sites. H2 can be administered exogenously and is also produced endogenously within the intestinal tract. A comprehensive understanding of its delivery mechanisms and modes of action is crucial for advancing hydrogen medicine. This review highlights H₂'s mechanisms of action, summarizes its administration methods, and explores advancements in treating intestinal diseases (e.g., inflammatory bowel disease, intestinal ischemia-reperfusion, colorectal cancer). Additionally, its applications in managing other diseases are discussed. Finally, the challenges associated with its clinical application and potential solutions are explored. We propose that current delivery challenges faced by H2 can be effectively addressed through the use of nanoplatforms; furthermore, interactions between hydrogen and gut microbiota may provide insights into its mechanisms for treating intestinal diseases. Future research should explore the synergistic effects of H2 in conjunction with conventional therapies and develop personalized treatment plans to achieve precision medicine.

IGFBP5 mediates the therapeutic effect of isoliquiritigenin in myocardial ischemia-reperfusion injury via AKT/GLUT4 regulated insulin resistance

Background

Myocardial ischemia/reperfusion injury (MIRI) is a critical problem in cardiovascular medicine, often occurring after coronary revascularization procedures or cardiopulmonary bypass. The characters of MIRI are both energy metabolism disturbances and severe myocardium insulin resistance (IR), which exacerbated myocardial damage and cell death. Isoliquiritigenin (ISL), a flavonoid derived from licorice roots (Glycyrrhiza spp.), has demonstrated protective effects on MIRI. However, the potential cardio-protective effects and mechanism of ISL in MIRI remain unclear.

Propose

In this study, we aimed to investigate ISL's therapeutic effects on MIRI. Moreover, we elucidate the underlying mechanisms of ISL regulated myocardium insulin resistance in vivo and in vitro.

Methods

In vivo, SD rats underwent left anterior descending coronary artery ligation/reperfusion to induce MIRI. Chest echocardiography was performed to monitor cardiac function post-reperfusion, followed by measurement of myocardial injury and IR markers. In vitro, H9C2 cardiomyocytes subjected to oxygen-glucose deprivation/reperfusion (OGD/R). Markers associated with myocardial injury and IR were assessed. Then, we identified potential therapeutic targets IGFBP5 for MIRI by network pharmacology and molecular docking analysis. Finally, lentivirus were used to silence or over-express IGFBP5 to elucidate the role of IGFBP5 in regulating the therapeutic effects of ISL on IR in MIRI.

Results

In the present study, In vivo experiments demonstrated that ISL attenuated myocardial infarct size, decreased serum markers of myocardial injury, improved left ventricular systolic function, and enhanced insulin sensitivity. In vitro data revealed that ISL ameliorated glucose uptake and cell survival rate. Furthermore, ISL increased AKT phosphorylation and upregulated membrane-bound GLUT4 (M-GLUT4) protein expression levels. These effects of ISL are mediated by the induction of IGFBP5, as demonstrated using gene-specific shRNA or overexpression for IGFBP5.

Conclusion

Our results reveal that ISL protects against myocardial damage caused by MIRI through the regulation of IR via the IGFBP5/AKT/GLUT4 pathway.

Molecular Hydrogen in the Treatment of Respiratory Diseases

Molecular hydrogen is gaining increasing attention as an antioxidant, anti-inflammatory, and antiapoptotic agent. Once considered an inert gas, it reveals current therapeutic potential among others in inflammatory diseases, cancer, and sports medicine, among others. The present review aims to provide a consistent summary of the findings of the last twenty years on the use of molecular hydrogen in major respiratory diseases, including allergies, asthma, COPD, pulmonary fibrosis, lung injury of various origins, as well as cancer and infections of the respiratory tract. In addition, the basic mechanisms through which molecular hydrogen exercises its biological activity on the respiratory system are described.

Hydrogen and Methane Detection in Breath in Response to Two Different Types of Dietary Fiber and Its Relationship to Postprandial Glucose Concentration in Obese Patients with Type 2 Diabetes and Normoglycemic Subjects

Background: The aim of this study was to investigate the relationship between postprandial glycemic levels based on flashmonitoring and the production of intestinal hydrogen (H2) and methane (CH4) gases based on the measurement of the amount of these gases in exhaled air. Materials and Methods: We studied 14 subjects with type 2 diabetes mellitus (T2DM) and 14 individuals without diabetes (control) with two food load tests, including two types of dietary fiber (inulin and guar gum), with the simultaneous determination of gases in exhaled air and the assessment of glucose levels. Results: All subjects in the control group had a significant increase in exhaled H2. OR for increased hydrogen production in patients with T2DM was 0.17 (95% CI 0.031-0.93, p = 0.043). The level of H2 in exhaled breath after food load in patients with T2DM was lower than in normoglycemic subjects. There was an inverse correlation between maximum glucose rise and maximum H2 in exhaled air after food load in normoglycemic subjects (r = -0.569, p = 0.034). Patients with T2DM had direct correlations between the level of CH4 in exhaled air and the parameters of postprandial glycemia in the lactulose test (p < 0.05). Conclusions: The confirmation of a causal relationship between decreased H2 production, increased intestinal CH4 production, and more severe postprandial glycemia may identify new therapeutic targets in the correction of postprandial glycemia in patients with T2DM.

Molecular Hydrogen Therapy Enhances Immune Markers in Treg, Plasma, Tr1 Cells, and KLRG1 Expression on Tc Cells: A Case of Acute SDH With Midline Shift and Uncal Herniation Post-decompressive Craniectomy

BACKGROUND/AIM

Subdural hematomas (SDH), often caused by head trauma, are serious with high mortality and long-term complications. Studies show that molecular hydrogen has neuroprotective effects, such as reducing oxidative stress, inflammation, and cell death. It may also protect mitochondria, support cell function, and regulate immune responses, making it a promising new treatment option for SDH. However, more research is needed to confirm its effectiveness and create treatment guidelines.

CASE REPORT

We present a 24-year-old man with SDH, along with a right-sided midline shift, uncal herniation, and dilated left pupil. Conventional treatments-craniectomy, hyperbaric oxygen, therapeutic hypothermia, and stem cell therapy-were essential for stabilizing his condition. In addition, we administered hydrogen capsules as a novel adjunct therapy, beginning daily treatment immediately upon admission. While recovery was primarily due to standard interventions, hydrogen therapy appeared to enhance immune markers, particularly Treg and plasma cells, with no adverse effects. This case indicates that hydrogen therapy may serve as a beneficial addition to established SDH management methods.

CONCLUSION

This case suggests that molecular hydrogen therapy may be a helpful adjunct treatment for SDH with midline shift. Conventional therapies, including craniectomy, hyperbaric oxygen, therapeutic hypothermia, and stem cell therapy, were vital to the patient's recovery, but hydrogen therapy may have contributed by modulating immune responses, particularly Treg and plasma cell activity. While these findings are encouraging, further research is necessary to confirm hydrogen therapy's benefits and its role alongside traditional neurocritical care treatments.

Effects of Hydrogen-Rich Water on Growth, Redox Homeostasis and Hormonal, Histological and Immune Systems in Rats Exposed to High Cage Density Stress

OBJECTIVES

This study investigated the impact of drinking hydrogen-rich water (HRW) on growth performance, organ weights, thiol/disulphide homeostasis, oxidative status and some hormonal, histopathological and immunohistochemical changes in rats fed in a restricted housing environment.

METHODS

The eight groups (each group [male/female] eight rats) comprised two control, two hydrogen, two stress and two stress + hydrogen. All animals were given feed and water ad libitum for 3 months. Control and HRW group rats were calculated according to weight and housed according to the Guide's housing condition. The stress group and stress + HRW group were housed in half the area of the Guide's housing condition according to their weight. The animal's weekly body weights were measured throughout the study. The animals were sacrificed in accordance with ethical rules. Then, biochemical analyses were performed on thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), cortisol, parathyroid hormone (PTH) and calcium (Ca2+), total thiol (TT), native thiol (NT), disulphide, disulphide/TT × 100, disulphide/NT × 100 and NT/TT × 100, malondialdehyde (MDA) and glutathione (GSH). Haematoxylin staining for histopathological and SOD-2 immunoreactivity was also assessed.

RESULTS

Results showed that live weight gain was higher in the HRW groups than in the stress group. Oxidant status in biochemical analyses decreased in the stress + HRW group compared to the stress group. TSH decreased in the stress group. FT4, cortisol and Ca2+ increased in the stress group.

CONCLUSIONS

The stress-related physiological parameters were reduced in the HRW + stress group compared to the stress group. HRW could be suggested when the organism is found in stressful conditions.

Biosafety and efficacy evaluation of a biodegradable Zn-Cu-Mn stent: A long-term study in porcine coronary artery

In this study, biodegradable Zn-Cu-Mn alloy stents were implanted into porcine coronary artery for 18 months, and the in vivo biosafety and efficacy as well as the degradation behavior were systematically studied. Results showed a rapid endothelialization of the target vessel was achieved at 1 month post-implantation. Although the lumen diameter loss and local inflammation were observed at the early stage, the stented blood vessel could gradually recover with time. The lumen diameter was already close to normal range at 12 months, indicating good bioefficacy of the stent. No adverse effect on blood indexes or local accumulation of Zn, Cu or Mn elements were found after implantation, neither the malapposition and thrombosis were observed, which exhibited good biosafety of the stents. The stent could maintain the basic structure and mechanical integrity at 6 months, and remained only approximately 26 % of the stent volume at 18 months, suggesting a desirable degradation rate. In general, the Zn-Cu-Mn alloy stent showed great advantages and prospects in clinical application.

Molecular hydrogen inhibits neuroinflammation and ameliorates depressive-like behaviors and short-term cognitive impairment in senescence-accelerated mouse prone 8 mice

BACKGROUND AND AIMS

Neuroinflammation, a low-grade chronic inflammation of the central nervous system, is linked to age-related neuropsychiatric disorders such as senile depression and Alzheimer's disease. Recent studies have explored controlling neuroinflammation as a novel treatment strategy. Molecular hydrogen shows anti-inflammatory effects. However, its impacts on neuroinflammation and age-related neuropsychiatric disorders remain unelucidated. We investigated molecular hydrogen's effects on microglial activation, neuroinflammation, depressive-like behavior, and short-term cognitive decline in senescence-accelerated mouse-prone 8 (SAMP8) mice.

METHODS

Six-week-old SAMP8 or senescence-accelerated mouse-resistant 1 (SAMR1) mice received hydrogen-rich jelly (HRJ) or placebo jelly (PJ) from six weeks of age for 26-28 weeks. Depressive-like behavior was assessed using tail suspension and forced swimming tests, while cognitive function was evaluated using the Y-maze and object recognition tests. Brain tissues were used for immunohistochemical studies or to measure pro-inflammatory cytokine levels via enzyme-linked immunosorbent assay (ELISA).

RESULTS

HRJ intake reduced immobility time in both tail suspension and forced swimming tests and enhanced visual cognitive and spatial working memory in SAMP8 mice. Additionally, HRJ intake suppressed the 8-hydroxy-2'-deoxyguanosine (8-OHdG), Iba1, and cleaved caspase 3 expression levels in the medial prefrontal cortex and hippocampal dentate gyrus. Furthermore, HRJ intake significantly lowered IL-6 levels in brain tissues of SAMP8 mice.

CONCLUSIONS

These findings suggest that molecular hydrogen treatment may regulate neuroinflammation induced by activated microglia and improve depressive-like behavior and short-term cognitive impairment in SAMP8 mice.

Molecular Hydrogen Modulates T Cell Differentiation and Enhances Neuro-Regeneration in a Vascular Dementia Mouse Model

This study explores whether molecular hydrogen (H2) administration can alleviate cognitive and immunological disturbances in a mouse model of vascular dementia (VaD). Adult male C57BL/6 mice underwent bilateral common carotid artery stenosis to induce VaD and were subsequently assigned to three groups: VaD, VaD with hydrogen-rich water treatment (VaD + H2), and Sham controls. Behavioral assessments using open field and novel object recognition tests revealed that VaD mice exhibited anxiety-deficient behavior and memory impairment, both of which were reversed by H2 treatment. Histological examinations showed pyknotic neuronal morphologies and elevated reactive oxygen species (ROS) in the VaD hippocampus, whereas H2 administration mitigated these alterations. Furthermore, VaD-induced downregulation of BCL2 was reversed in the VaD + H2 group, in parallel with increased IL-4 expression. Flow cytometric analyses revealed that VaD disrupted T regulatory cell homeostasis by significantly increasing their proportion, an effect reversed by H2 treatment, thereby restoring immunological balance. Transcriptomic evaluations confirmed that VaD suppressed key neuroprotective and anti-inflammatory genes, while H2 treatment restored or enhanced their expression. Collectively, these findings highlight the neuroprotective and immuno-modulatory potential of molecular hydrogen, suggesting that H2 supplementation may promote neuronal resilience, modulate T cell differentiation, and support cognitive recovery in vascular dementia.

Efficacy of a hydrogen-oxygen generator in treating cigarette smoke-induced chronic obstructive pulmonary disease in rats

Current treatments for chronic obstructive pulmonary disease (COPD), a common respiratory condition, include oxygen therapy and steroids for temporary relief. In this study, we established a rat model of cigarette smoke (CS)-induced COPD and investigated the benefits of a hydrogen-oxygen generator in this model. CS-exposed rats were treated using either a hydrogen-oxygen generator or a steroid. A hydrogen-oxygen generator reduced the neutrophil, lymphocyte, and eosinophil counts compared to natural recovery, whereas steroid treatment increased the total white blood cell, neutrophil, lymphocyte, monocyte and eosinophil counts. Furthermore, the mean linear intercept and the mean alveolar number were 59.8%, and 188.3%, respectively, after treatment with the generator, compared to the values observed with natural recovery. Finally, the generator increased the tricuspid annular plane systolic excursion values by 113.1% compared with the values in natural recovery. Our findings indicate successful establishment of a rat model of CS-induced COPD and demonstrate the potential benefits of using a hydrogen-oxygen generator for COPD patients.

Synergistic Antioxidant Effects of Molecular Hydrogen and Cold Atmospheric Plasma in Enhancing Mesenchymal Stem Cell Therapy

In regenerative medicine, mesenchymal stem cells (MSCs) have shown their importance and potential in tissue reconstruction and immune system modification. However, such cells' potential is often diminished by factors such as oxidative stress, immune rejection, and inadequate engraftment. This review highlights the role of molecular hydrogen (H2) and cold atmospheric plasma (CAP) as adjunct therapies to improve the effectiveness of MSC therapy. H2 has strong antioxidative and anti-inflammatory actions as it quenches reactive oxygen species and positively stimulates the Nrf2 pathway that promotes MSC survival and life. CAP, being a modulated source of ROS and RNS, also assists MSCs by altering the cellular redox balance, thus facilitating cellular adaptation, migration, and differentiation. H2 and CAP in conjunction with each other assist in establishing an ambience favorable for promoting MSCs' survival and growth abilities, and reduce the healing time in various pathways such as wound, neuroprotection, and ischemia. Besides these concerns, this review also covers the best administration routes and doses of H2 and CAP together with MSCs in therapy. This study informs on a novel dual method aimed at improving the outcome of MSC therapy while adding several molecular targets and relevant clinical uses concerning these therapies. Research of the future has to deal with bettering these protocols so that the therapeutic benefits can be maximized without long-term implications for clinical applications.

Inhalation of Hydrogen-rich Gas before Acute Exercise Alleviates Exercise Fatigue: A Randomized Crossover Study

Hydrogen, as an antioxidant, may have the potential to mitigate fatigue and improve selected oxidative stress markers induced by strenuous exercise. This study focused on a previously unexplored approach involving pre-exercise inhalation of hydrogen-rich gas (HRG). Twenty-four healthy adult men first completed pre-laboratories to determine maximum cycling power (Wmax) and maximum cycling time (Tmax). Then they were subjected to ride Tmax at 80% Wmax and 60-70 rpm on cycle ergometers after inhaled HRG or placebo gas (air) for 60-minute in a double-blind, counterbalanced, randomized, and crossover design. The cycling frequency in the fatigue modeling process and the rating of perceived exertion (RPE) at the beginning and end of the ride were recorded. Before gas inhalation and after fatigue modeling, visual analog scale (VAS) for fatigue and counter-movement jump (CMJ) were tested, and blood samples were obtained. The results showed that compared to a placebo, HRG inhalation induced significant improvement in VAS, RPE, the cycling frequency during the last 30 seconds in the fatigue modeling process, the ability to inhibit hydroxyl radicals, and serum lactate after exercise (p<0.028), but not in CMJ height and glutathione peroxidase activity. The cycling frequency during the last 30 seconds of all other segments in the fatigue modeling process was within the range of 60-70 rpm. In conclusion, HRG inhalation prior to acute exercise can alleviate exercise-induced fatigue, maintain functional performance, and improve hydroxyl radical and lactate levels.

Regulation of hydrogen rich water on strawberry seedlings and root endophytic bacteria under salt stress

Salt stress could lead to plant growth barriers and crop yield reduction. Strawberries are sensitive to salt stress, and improving salt tolerance is important for strawberry production. This study aimed to explore the potential of hydrogen-rich water (HRW) to enhance salt tolerance in strawberries. Through pot experiments, we investigated how HRW affects plant growth, ion absorption, osmotic stress, oxidative stress, antioxidant enzyme levels, hormone levels, and root endophytic bacteria in strawberry seedlings under salt stress. The results showed that under 100 mM NaCl treatment, 50% and 100% HRW treatments significantly increased strawberry biomass by 0.29 g and 0.54g, respectively, wherein, 100% HRW significantly increased the shoot and root length by 15.34% and 24.49%, respectively. In addition, under salt stress the absorption of K+ by strawberry seedlings was increased with the HRW supplement, while the absorption of Na+ was reduced. Meanwhile, HRW treatment reduced the transfer of Na+ from root to shoot. Furthermore, under salt stress, HRW treatment increased the relative water content (RWC) by 12.35%, decreased the electrolyte leakage rate (EL) by 7.56%. HRW modulated phytohormone levels in strawberry seedlings, thereby alleviating the salt stress on strawberries. Moreover, HRW was found to promote plant growth by altering the diversity of bacteria in strawberry roots and recruiting specific microorganisms, such as Tistella. Our findings indicate that HRW could help restore the microecological homeostasis of strawberry seedlings, thus further mitigating salt stress. This study provides a novel perspective on the mechanisms by which HRW alleviates salt stress, thereby enriching the scientific understanding of hydrogen's applications in agriculture.

Molecular Hydrogen Therapy in Aneurysmal SAH With RA and Newly-diagnosed SLE, Complicated With Acute Ischemic Infarction: A Case Report of Improved Immune Markers Including Tr1 Cells, Breg Cells and TIM3 Expression on Tc Cells

BACKGROUND/AIM

Most nontraumatic subarachnoid hemorrhages (SAHs) are caused by ruptured saccular aneurysms, often resulting in a devastating clinical event characterized by high mortality and significant morbidity among survivors. Numerous studies have confirmed the neuroprotective effects of the molecular hydrogen due to its unique biological properties.

CASE REPORT

We present the case of a 44-year-old female with aneurysmal SAH with rheumatoid arthritis (RA) and newly diagnosed systemic lupus erythematosus (SLE), complicated by acute ischemic infarction. Despite surgical, pharmacological and non-pharmacological interventions, including embolization of the aneurysm, immunosuppressant, non-vitamin K antagonist oral anticoagulant (NOAC), and plasmapheresis, loss of consciousness continued. The patient began daily treatment with hydrogen capsules, resulting in increased in Treg cells, Breg cells, increased TIM3+ expression on Tc cells, and the conversion of anti-dsDNA from positive to negative. Her clinical symptoms stabilized without adverse effects.

CONCLUSION

This case highlights the potential benefits of molecular hydrogen therapy in managing aneurysmal SAH with underlying autoimmune disease, warranting further research.

The Role of Mast Cells in the Remodeling Effects of Molecular Hydrogen on the Lung Local Tissue Microenvironment under Simulated Pulmonary Hypertension

Molecular hydrogen (H2) has antioxidant, anti-inflammatory, and anti-fibrotic effects. In a rat model simulating pulmonary fibrotic changes induced by monocrotaline-induced pulmonary hypertension (MPH), we had previously explored the impact of inhaled H2 on lung inflammation and blood pressure. In this study, we further focused the biological effects of H2 on mast cells (MCs) and the parameters of the fibrotic phenotype of the local tissue microenvironment. MPH resulted in a significantly increased number of MCs in both the pneumatic and respiratory parts of the lungs, an increased number of tryptase-positive MCs with increased expression of TGF-β, activated interaction with immunocompetent cells (macrophages and plasma cells) and fibroblasts, and increased MC colocalization with a fibrous component of the extracellular matrix of connective tissue. The alteration in the properties of the MC population occurred together with intensified collagen fibrillogenesis and an increase in the integral volume of collagen and elastic fibers of the extracellular matrix of the pulmonary connective tissue. The exposure of H2 together with monocrotaline (MCT), despite individual differences between animals, tended to decrease the intrapulmonary MC population and the severity of the fibrotic phenotype of the local tissue microenvironment compared to changes in animals exposed to the MCT effect alone. In addition, the activity of collagen fibrillogenesis associated with MCs and the expression of TGF-β and tryptase in MCs decreased, accompanied by a reduction in the absolute and relative content of reticular and elastic fibers in the lung stroma. Thus, with MCT exposure, inhaled H2 has antifibrotic effects involving MCs in the lungs of rats. This reveals the unknown development mechanisms of the biological effects of H2 on the remodeling features of the extracellular matrix under inflammatory background conditions of the tissue microenvironment.

Hydrogen-Rich Water to Enhance Exercise Performance: A Review of Effects and Mechanisms

Background: Hydrogen-rich water (HRW) has garnered significant interest within the sports and exercise science community due to its selective antioxidant properties. Despite its potential benefits, comprehensive reviews specifically addressing its effects on athletic performance are limited. This review aims to assess the impact of HRW on sports performance and explore the underlying molecular biological mechanisms, with the goal of elucidating how HRW might enhance athletic performance. Methods: This review synthesizes research on HRW by examining articles published between 1980 and April 2024 in databases such as PubMed, the Cochrane Library, Embase, Scopus, and Web of Science. Results: It highlights HRW's effects on various aspects of athletic performance, including endurance, strength, sprint times, lunge movements, countermovement jump height, and time to exhaustion. While the precise mechanisms by which HRW affects athletic performance remain unclear, this review investigates its general molecular biological mechanisms beyond the specific context of sports. This provides a theoretical foundation for future research aimed at understanding how HRW can enhance athletic performance. HRW targets the harmful reactive oxygen and nitrogen species produced during intense exercise, thereby reducing oxidative stress-a critical factor in muscle fatigue, inflammation, and diminished athletic performance. HRW helps to scavenge hydroxyl radicals and peroxynitrite, regulate antioxidant enzymes, mitigate lipid peroxidation, reduce inflammation, protect against mitochondrial dysfunction, and modulate cellular signaling pathways. Conclusions: In summary, while a few studies have indicated that HRW may not produce significant beneficial effects, the majority of research supports the conclusion that HRW may enhance athletic performance across various sports. The potential mechanisms underlying these benefits are thought to involve HRW's role as a selective antioxidant, its impact on oxidative stress, and its regulation of redox homeostasis. However, the specific molecular biological mechanisms through which HRW improves athletic performance remain to be fully elucidated.

Using oral molecular hydrogen supplements to combat microinflammation in humans: a pilot observational study

Background: Persistent inflammation over time can cause gradual harm to the body. Molecular hydrogen has the potential to specifically counteract reactive oxygen species (ROS), reduce disease severity, and enhance overall health. Investigations of the anti-inflammatory and antioxidant properties of oral solid hydrogen capsules (OSHCs) are currently limited, prompting our examination of the beneficial effects of OSHCs. Subsequently, we conducted a clinical study to assess the impact of OSHCs supplementation on individuals with chronic inflammation. Materials and methods: Initially, we evaluated the oxidative reduction potential (ORP) properties of the OSHCs solution by comparing it to hydrogen-rich water (HRW) and calcium hydride (CaH2) treated water. In our outpatient department, stable patients with chronic illnesses who were treated with varying doses of OSHCs were randomized into low-, medium-, and high-dose groups for 4 weeks. Primary outcomes included changes in the serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) concentrations after four weeks of OSHCs consumption. Secondary outcomes included changes in the Brief Fatigue Inventory-Taiwan (BFI-T) fatigue scale, Control Status Scale for Diabetes (CSSD70) scores, and Disease Activity Score 28 (DAS28). Results: Compared to HRW and CaH2, OSHCs demonstrated a prolonged reduction in ORP for 60 minutes in vitro and enabled a regulated release of hydrogen over 24 hours. A total of 30 participants, with 10 in each dosage (low/medium/high) group, completed the study. The average ESR120 significantly decreased from the first week to the fourth week, with a noticeable dose effect (low-dose group, p = 0.494; high-dose group, p = 0.016). Overall, the average CRP concentration showed a distinct decreasing trend after four weeks of OSHCs administration (w0 vs. w4, p = 0.077). The average DAS28 score demonstrated a significant decrease following OSHCs treatment. Furthermore, there were improvements in the BFI-T and CSSD70 scores. Conclusion: OSHCs supplementation may exert anti-inflammatory and antioxidant effects on individuals with chronic inflammation. However, further clinical studies could be investigated to explore the potential therapeutic effects of OSHCs.

The impact of hydrogen inhalation therapy on blood reactive oxygen species levels: A randomized controlled study

Reactive Oxygen Species (ROS) play a key role in physiological processes. However, the imbalance between ROS and antioxidants in favor of the former causes oxidative stress linked to numerous pathologies. Due to its unique attributes, including distinguished permeability and selective antioxidant capability, molecular hydrogen (H2) has become an essential therapeutic agent. Hydrogen Inhalation Therapy (HIT) has come to light as a promising strategy to counteract oxidative stress. In this randomized controlled study, we aimed to evaluate the effectiveness of HIT in reducing blood ROS levels. 37 participants with elevated ROS levels (d-ROMs value > 350 U.CARR) were enrolled in the study. Participants were divided into test and control groups. The test group participants received HIT, and then their blood ROS levels were measured immediately post-treatment and after 24 h. Their results were compared to those of the control group participants who did not undergo HIT. The test group demonstrated a significant reduction in blood ROS levels after the treatment. These findings suggested the efficacy of HIT in reducing oxidative stress.

Hydrogen Attenuates Cognitive Impairment in Rat Models of Vascular Dementia by Inhibiting Oxidative Stress and NLRP3 Inflammasome Activation

Vascular dementia (VaD) is the second most common form of dementia worldwide. Oxidative stress and neuroinflammation are important factors contributing to cognitive dysfunction in patients with VaD. The antioxidant and anti-inflammatory properties of hydrogen are increasingly being utilized in neurological disorders, but conventional hydrogen delivery has the disadvantage of inefficiency. Therefore, magnesium silicide nanosheets (MSNs) are used to release hydrogen in vivo in larger quantities and for longer periods of time to explore the appropriate dosage and regimen. In this study, it is observed that hydrogen improved learning and working memory in VaD rats in the Morris water maze and Y-maze, which elicits improved cognitive function. Nissl staining of neurons shows that hydrogen treatment significantly improves edema in neuronal cells. The expression and activation of reactive oxygen species (ROS), Thioredoxin-interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), caspase-1, and IL-1β in the hippocampus are measured via ELISA, Western blotting, real-time qPCR, and immunofluorescence. The results show that oxidative stress indicators and inflammasome-related factors are significantly decreased after 7dMSN treatment. Therefore, it is concluded that hydrogen can ameliorate neurological damage and cognitive dysfunction in VaD rats by inhibiting ROS/NLRP3/IL-1β-related oxidative stress and inflammation.

Deep Red Light Driven Hydrogen Evolution by Heterojunction Polymer Dots for Diabetic Wound Healing

We describe small heterojunction polymer dots (Pdots) with deep-red light catalyzed H2 generation for diabetic skin wound healing. The Pdots with donor/acceptor heterojunctions showed remarkably enhanced photocatalytic activity as compared to the donor or acceptor nanoparticles alone. We encapsulate the Pdots and ascorbic acid into liposomes to form Lipo-Pdots nanoreactors, which selectively scavenge ⋅OH radicals in live cells and tissues under 650 nm light illumination. The antioxidant capacity of the heterojunction Pdots is ~10 times higher than that of the single-component Pdots described previously. Under a total light dose of 360 J/cm2, the Lipo-Pdots nanoreactors effectively scavenged ⋅OH radicals and suppressed the expression of pro-inflammatory cytokines in skin tissues, thereby accelerating the healing of skin wounds in diabetic mice. This study provides a feasible solution for safe and effective treatment of diabetic foot ulcers.

Potential role of molecular hydrogen therapy on oxidative stress and redox signaling in chronic kidney disease

Oxidative stress plays a key role in chronic kidney disease (CKD) development and progression, inducing kidney cell damage, inflammation, and fibrosis. However, effective therapeutic interventions to slow down CKD advancement are currently lacking. The multifaceted pharmacological effects of molecular hydrogen (H2) have made it a promising therapeutic avenue. H2 is capable of capturing harmful •OH and ONOO- while maintaining the crucial reactive oxygen species (ROS) involved in cellular signaling. The NRF2-KEAP1 system, which manages cell redox balance, could be used to treat CKD. H2 activates this pathway, fortifying antioxidant defenses and scavenging ROS to counteract oxidative stress. H2 can improve NRF2 signaling by using the Wnt/β-catenin pathway and indirectly activate NRF2-KEAP1 in mitochondria. Additionally, H2 modulates NF-κB activity by regulating cellular redox status, inhibiting MAPK pathways, and maintaining Trx levels. Treatment with H2 also attenuates HIF signaling by neutralizing ROS while indirectly bolstering HIF-1α function. Furthermore, H2 affects FOXO factors and enhances the activity of antioxidant enzymes. Despite the encouraging results of bench studies, clinical trials are still limited and require further investigation. The focus of this review is on hydrogen's role in treating renal diseases, with a specific focus on oxidative stress and redox signaling regulation, and it discusses its potential clinical applications.

A Novel Antioxidant, Hydrogen-Rich Coral Calcium Alters Gut Microbiome and Bile Acid Synthesis to Improve Methionine-and-Choline-Deficient Diet-Induced Non-Alcoholic Fatty Liver Disease

The prevalence of non-alcoholic fatty liver disease (NAFLD) has dramatically increased in recent years, and it is highly associated with metabolic diseases, as well as the development of hepatocellular carcinoma. However, effective therapeutic strategies for the treatment of NAFLD are still scarce. Although hydrogen-rich water shows beneficial effects for hepatic steatosis, the inconvenience limits the application of this antioxidant. In light of this, hydrogen-rich coral calcium (HRCC) was developed due to its convenience and quantifiable characteristics. However, the effects of HRCC on NAFLD are still unknown. In the present study, we found that HRCC treatment improved methionine-and-choline-deficient diet (MCD)-induced hepatic steatosis, increased aspartate aminotransferase and alanine aminotransferase levels, and elevated hepatic inflammatory factor expressions in mice. In addition to the increased expressions of antioxidative enzymes, we found that HRCC increased the expressions of bile acid biosynthesis-related genes, including Cyp8b1 and Cyp27a1. Increased hepatic bile acid contents, such as muricholic acids, 23 nor-deoxycholic acid, glycoursodeoxycholic acid, and cholic acids, were also confirmed in MCD mice treated with HRCC. Since the biogenesis of bile acids is associated with the constitution of gut microbiome, the alterations in gut microbiome by HRCC were evaluated. We found that HRCC significantly changed the constitution of gut microbiome in MCD mice and increased the contents of Anaerobacterium, Acutalibacter, Anaerosacchariphilus, and Corynebacterium. Taken together, HRCC improved MCD-induced NAFLD through anti-inflammatory mechanisms and by increasing antioxidative activities. Additionally, HRCC might alter gut microbiome to change hepatic bile acid contents, exerting beneficial effects for the treatment of NAFLD.

The role of hydrogen in the prevention and treatment of coronary atherosclerotic heart disease

Coronary atherosclerotic heart disease (CHD) is a primary cardiovascular disease caused by atherosclerosis (AS), which is characterized by chronic inflammation and lipid oxidative deposition. Molecular hydrogen (H2) is an effective anti-inflammatory agent and has potential to ameliorate glycolipid metabolism disorders, which is believed to exert beneficial effects on the prevention and treatment of CHD. It is suggested that H2 reduces inflammation in CHD by regulating multiple pathways, including NF-κB inflammatory pathway, pyroptosis, mitophagy, endoplasmic reticulum (ER) stress, and Nrf2 antioxidant pathway. Additionally, H2 may improve glycolipid metabolism by mediation of PI3K and AMPK signalling pathways, contributing to inhibition of the occurrence and development of CHD. This review elaborates pathogenesis of CHD and evaluates the role of H2 in CHD. Moreover, possible molecular mechanisms have been discussed and speculated, aiming to provide more strategies and directions for subsequent studies of H2 in CHD.

Hydrogen gas inhalation ameliorates LPS-induced BPD by inhibiting inflammation via regulating the TLR4-NFκB-IL6/NLRP3 signaling pathway in the placenta

INTRODUCTION

Hydrogen (H2) is regarded as a novel therapeutic agent against several diseases owing to its inherent biosafety. Bronchopulmonary dysplasia (BPD) has been widely considered among adverse pregnancy outcomes, without effective treatment. Placenta plays a role in defense, synthesis, and immunity, which provides a new perspective for the treatment of BPD. This study aimed to investigate if H2 reduced the placental inflammation to protect the neonatal rat against BPD damage and potential mechanisms.

METHODS

We induced neonatal BPD model by injecting lipopolysaccharide (LPS, 1 µg) into the amniotic fluid at embryonic day 16.5 as LPS group. LPS + H2 group inhaled 42% H2 gas (4 h/day) until the samples were collected. We primarily analyzed the neonatal outcomes and then compared inflammatory levels from the control group (CON), LPS group and LPS + H2 group. HE staining was performed to evaluate inflammatory levels. RNA sequencing revealed dominant differentially expressed genes. Bioinformatics analysis (GO and KEGG) of RNA-seq was applied to mine the signaling pathways involved in protective effect of H2 on the development of LPS-induced BPD. We further used qRT-PCR, Western blot and ELISA methods to verify differential expression of mRNA and proteins. Moreover, we verified the correlation between the upstream signaling pathways and the downstream targets in LPS-induced BPD model.

RESULTS

Upon administration of H2, the inflammatory infiltration degree of the LPS-induced placenta was reduced, and infiltration significantly narrowed. Hydrogen normalized LPS-induced perturbed lung development and reduced the death ratio of the fetus and neonate. RNA-seq results revealed the importance of inflammatory response biological processes and Toll-like receptor signaling pathway in protective effect of hydrogen on BPD. The over-activated upstream signals [Toll-like receptor 4 (TLR4), nuclear factor kappa-B p65 (NF-κB p65), Caspase1 (Casp1) and NLR family pyrin domain containing 3 (NLRP3) inflammasome] in LPS placenta were attenuated by H2 inhalation. The downstream targets, inflammatory cytokines/chemokines [interleukin (IL)-6, IL-18, IL-1β, C-C motif chemokine ligand 2 (CCL2) and C-X-C motif chemokine ligand 1 (CXCL1)], were decreased both in mRNA and protein levels by H2 inhalation in LPS-induced placentas to rescue them from BPD. Correlation analysis displayed a positive association of TLR4-mediated signaling pathway both proinflammatory cytokines and chemokines in placenta.

CONCLUSION

H2 inhalation ameliorates LPS-induced BPD by inhibiting excessive inflammatory cytokines and chemokines via the TLR4-NFκB-IL6/NLRP3 signaling pathway in placenta and may be a potential therapeutic strategy for BPD.

Mesenchymal Stem Cell Priming: Potential Benefits of Administration of Molecular Hydrogen

Stem cell therapy has emerged as a promising avenue for regenerative medicine, offering the potential to treat a wide range of debilitating diseases and injuries. Among the various types of stem cells, mesenchymal stem cells (MSCs) have garnered significant attention due to their unique properties and therapeutic potential. In recent years, researchers have been exploring novel approaches to enhance the effectiveness of MSC-based therapies. One such approach that has gained traction is the priming of MSCs with molecular hydrogen (H2). This article delves into the fascinating world of mesenchymal stem cell priming with molecular hydrogen and the potential benefits it holds for regenerative medicine.

Effect of molecular hydrogen, a novelly-established antioxidant, on the retinal degeneration of hereditary retinitis pigmentosa: an in-vivo study

Objective Our research was performed in order to explore the effects of molecular hydrogen (H2), a novelly-established antioxidant, on the retinal degeneration in rd1 mice, an animal model of inherited retinitis pigmentosa (RP). Methods The rd1 mice were divided randomly into control and H2 intervention groups. Mice from other groups received H2 intervention in three modes, two modes of the hydrogen gas (HG) and one model of hydrogen-rich saline (HRS). At 14 days post born (P14) and P21, various indicators were detected in all mice, including eletroretinogram (ERG), fundus phography, optical coherence tomography (OCT), and retinal immunotaining of microglia cells' marker, Iba1. Results The ERG amplitude in mice from the control and H2 intervention groups showed no statistical differences (p > 0.05). At P14 and P21, no significant difference in the distance from the retinal pigment epithelium to the outer plexiform layer on OCT from mice of the above two groups was found (p > 0.05). The thickness of the outer nuclear layer (ONL) in mice at P14 and P21 showed no statistical differences between the control group and the H2 intervention group (p > 0.05). In the aspect of the number of Iba1-positive cells, we did not found any significant differences between the two groups (p > 0.05). Conclusion Different forms of H2 intervention (hydrogen-rich saline and hydrogen gas) had no obvious effects on the course of retinal degeneration in rd1 mice. The specific mechanism of photoreceptor degeneration in the hereditary RP mouse model may be different, requiring different medical interventions.

Hydrogen-rich solvent method in phytochemical extraction: Potential mechanisms and perspectives

INTRODUCTION

Phytochemicals are used in many products, including foods, beverages, pharmaceuticals, and cosmetics. The extraction of phytochemicals is considered one of the best solutions to valorize these underestimated materials. Many methods have been developed to efficiently extract phytochemicals at high quality, high purity, and low costs without harming the environment. Recently, molecular hydrogen (H2 ) has shown its ability to improve the extraction of phytochemicals from plant materials. Due to its unique physicochemical and biological properties, H2 showed an efficient ability to extract phenolics and antioxidants at high yields with cost-effective potential. Without sophisticated equipment and high energy and solvent consumption, the hydrogen extraction method is a green and applicable alternative for the extraction of phytochemicals.

OBJECTIVES

This review aims to provide the latest knowledge and results concerning the studies on using hydrogen-rich solvents to extract phytochemicals from different agri-food wastes, by-products, and other plant materials.

MATERIALS AND METHODS

Recent literature relating to extracting phytochemicals by the hydrogen-rich solvent method and its potential mechanisms is summarized to provide a basic understanding of how hydrogen can improve the extraction of phytochemicals.

RESULTS

This review describes, for the first time, the practical procedure of how researchers and laboratories can apply the hydrogen extraction method under safe conditions at a low-budget scale. The review provides some examples of the hydrogen extraction method and the mechanisms and rationale behind its effectiveness.

CONCLUSIONS

It can be concluded that the hydrogen-rich solvent method is a green and cost-effective method for extracting phytochemicals from different plant materials.

Molecular hydrogen attenuates sepsis-induced cardiomyopathy in mice by promoting autophagy

BACKGROUND

Approximately 40 to 60% of patients with sepsis develop sepsis-induced cardiomyopathy (SIC), which is associated with a substantial increase in mortality. We have found that molecular hydrogen (H2) inhalation improved the survival rate and cardiac injury in septic mice. However, the mechanism remains unclear. This study aimed to explore the regulatory mechanism by which hydrogen modulates autophagy and its role in hydrogen protection of SIC.

METHODS

Cecal ligation and puncture (CLP) was used to induce sepsis in adult C57BL/6J male mice. The mice were randomly divided into 4 groups: Sham, Sham + 2% hydrogen inhalation (H2), CLP, and CLP + H2 group. The 7-day survival rate was recorded. Myocardial pathological scores were calculated. Myocardial troponin I (cTnI) levels in serum were detected, and the levels of autophagy- and mitophagy-related proteins in myocardial tissue were measured. Another four groups of mice were also studied: CLP, CLP + Bafilomycin A1 (BafA1), CLP + H2, and CLP + H2 + BafA1 group. Mice in the BafA1 group received an intraperitoneal injection of the autophagy inhibitor BafA1 1 mg/kg 1 h after operation. The detection indicators remained the same as before.

RESULTS

The survival rate of septic mice treated with H2 was significantly improved, myocardial tissue inflammation was improved, serum cTnI level was decreased, autophagy flux was increased, and mitophagy protein content was decreased (P < 0.05). Compared to the CLP + H2 group, the CLP + H2 + BafA1 group showed a decrease in autophagy level and 7-day survival rate, an increase in myocardial tissue injury and cTnI level, which reversed the protective effect of hydrogen (P < 0.05).

CONCLUSION

Hydrogen exerts protective effect against SIC, which may be achieved through the promotion of autophagy and mitophagy.

A strategy of novel molecular hydrogen-producing antioxidative auxiliary system improves virus production in cell bioreactor

In the increasing demand for virus vaccines, large-scale production of safe, efficient, and economical viral antigens has become a significant challenge. High-cell-density manufacturing processes are the most commonly used to produce vaccine antigens and protein drugs. However, the cellular stress response in large-scale cell culture may directly affect host cell growth and metabolism, reducing antigen production and increasing production costs. This study provided a novel strategy of the antioxidant auxiliary system (AAS) to supply molecular hydrogen (H2) into the cell culture media via proton exchange membrane (PEM) electrolysis. Integrated with a high-density cell bioreactor, the AAS aims to alleviate cellular stress response and increase viral vaccine production. In the results, the AAS stably maintained H2 concentration in media even in the high-air exposure tiding cell bioreactor. H2 treatment was shown safe to cell culture and effectively alleviated oxidative stress. In two established virus cultures models, bovine epidemic fever virus (BEFV) and porcine circovirus virus type 2 (PCV-2), were employed to verify the efficacy of AAS. The virus yield was increased by 3.7 and 2.5 folds in BEFV and PCV-2 respectively. In conclusion, the AAS-connected bioreactor effectively alleviated cellular oxidative stress and enhanced virus production in high-density cell culture.

Hydrogen Regulates Ulcerative Colitis by Affecting the Intestinal Redox Environment

The redox balance in the intestine plays an important role in maintaining intestinal homeostasis, and it is closely related to the intestinal mucosal barrier, intestinal inflammation, and the gut microbiota. Current research on the treatment of ulcerative colitis has focused on immune disorders, excessive inflammation, and oxidative stress. However, an imbalance in intestinal redox reaction plays a particularly critical role. Hydrogen is produced by some anaerobic bacteria via hydrogenases in the intestine. Increasing evidence suggests that hydrogen, as an inert gas, is crucial for immunity, inflammation, and oxidative stress and plays a protective role in ulcerative colitis. Hydrogen maintains the redox state balance in the intestine in ulcerative colitis and reduces damage to intestinal epithelial cells by exerting its selective antioxidant ability. Hydrogen also regulates the intestinal flora, reduces the harmful effects of bacteria on the intestinal epithelial barrier, promotes the restoration of normal anaerobic bacteria in the intestines, and ultimately improves the integrity of the intestinal epithelial barrier. The present review focuses on the therapeutic mechanisms of hydrogen-targeting ulcerative colitis.

Hydrogen Water: Extra Healthy or a Hoax?-A Systematic Review

Hydrogen-rich water (HRW) has emerged as a novel approach in the field of health and wellness. It is believed to have therapeutic antioxidant properties that can neutralize harmful free radicals in the human body. It has also been shown to be beneficial in mitigating oxidative stress-induced damage through its anti-inflammatory and anti-apoptotic pathways. We aim to conduct a systematic review to evaluate the potential benefits of hydrogen-rich water. The review protocol was uploaded on PROSPERO. After the initial search criteria, the articles were reviewed by two blinded investigators, and a total of 25 articles were included in the systematic review. The potential benefits of hydrogen-rich water on various aspects of health, including exercise capacity, physical endurance, liver function, cardiovascular disease, mental health, COVID-19, oxidative stress, and anti-aging research, are a subject of growing interest and ongoing research. Although preliminary results in clinical trials and studies are encouraging, further research with larger sample sizes and rigorous methodologies is needed to substantiate these findings. Current research needs to fully explain the mechanisms behind the potential benefits of hydrogen-rich water. Continued scientific exploration will provide valuable insights into the potential of hydrogen-rich water as an adjunctive therapeutic approach in the future.

Application of Electrolyzed Hydrogen Water for Management of Chronic Kidney Disease and Dialysis Treatment-Perspective View

Chronic kidney disease (CKD), which is globally on the rise, has become an urgent challenge from the perspective of public health, given its risk factors such as end-stage renal failure, cardiovascular diseases, and infections. The pathophysiology of CKD, including dialysis patients, is deeply associated with enhanced oxidative stress in both the kidneys and the entire body. Therefore, the introduction of a safe and widely applicable antioxidant therapy is expected as a measure against CKD. Electrolyzed hydrogen water (EHW) generated through the electrolysis of water has been confirmed to possess chemical antioxidant capabilities. In Japan, devices producing this water have become popular for household drinking water. In CKD model experiments conducted to date, drinking EHW has been shown to suppress the progression of kidney damage related to hypertension. Furthermore, clinical studies have reported that systemic oxidative stress in patients undergoing dialysis treatment using EHW is suppressed, leading to a reduction in the incidence of cardiovascular complications. In the future, considering EHW as one of the comprehensive measures against CKD holds significant importance. The medical utility of EHW is believed to be substantial, and further investigation is warranted.

Isoliquiritigenin, a potential therapeutic agent for treatment of inflammation-associated diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice is a medicinal herb with a 2000-year history of applications in traditional Chinese medicine. Isoliquiritigenin (ISL) is a bioactive chalcone compound isolated from licorice. It has attracted increasing attention in recent years due to its excellent anti-inflammatory activity.

AIM OF THE STUDY

This study is to provide a comprehensive summary of the anti-inflammatory activity of ISL and the underlying molecular mechanisms, and discuss new insights for its potential clinical applications as an anti-inflammation agent.

MATERIALS AND METHODS

We examined literatures published in the past twenty years from PubMed, Research Gate, Web of Science, Google Scholar, and SciFinder, with single or combined key words of "isoliquiritigenin", "inflammation", and "anti-inflammatory".

RESULTS

ISL elicits its anti-inflammatory activity by mediating various cellular processes. It inhibits the upstream of the nuclear factor kappa B (NF-κB) pathway and activates the nuclear factor erythroid related factor 2 (Nrf2) pathway. In addition, it suppresses the NOD-like receptor protein 3 (NLRP3) pathway and restrains the mitogen-activated protein kinase (MAPK) pathway.

CONCLUSIONS

Current studies indicate a great therapeutical potential of ISL as a drug candidate for treatment of inflammation-associated diseases. However, the pharmacokinetics, biosafety, and bioavailability of ISL remain to be further investigated.

Effects of Molecular Hydrogen in the Pathophysiology and Management of Cardiovascular and Metabolic Diseases

Diet and lifestyle choices, notably the Western-type diet, are implicated in oxidative stress and inflammation, factors that elevate the risk of cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2DM). In contrast, the Mediterranean of diet, rich in antioxidants, appears to have protective effects against these risks. This article highlights the dual role of diet in generating molecular hydrogen ( H 2 ) in the gut, and H 2 's subsequent influence on the pathophysiology and prevention of CVD and T2DM. Dietary fiber, flavonoids, and probiotics contribute to the production of liters of H 2 in the gut, functioning as antioxidants to neutralize free radicals and dampen inflammation. In the last two decades, mounting evidence has demonstrated that both endogenously produced and exogenously administered H 2 , whether via inhalation or H 2 -rich water (HRW), have potent anti-inflammatory effects across a wide range of biochemical and pathophysiological processes. Recent studies indicate that H 2 can neutralize hydroxyl and nitrosyl radicals, acting as a cellular antioxidant, thereby reducing oxidative stress and inflammation-leading to a significant decline in CVDs and metabolic diseases. Clinical and experimental research support the therapeutic potential of H 2 interventions such as HRW in managing CVDs and metabolic diseases. However, larger studies are necessary to verify the role of H 2 therapy in the management of these chronic diseases.

The role of hydrogen therapy in Alzheimer's disease management: Insights into mechanisms, administration routes, and future challenges

Alzheimer's disease (AD) is a progressive neurodegenerative disorder predominantly affecting the elderly. While conventional pharmacological therapies remain the primary treatment for AD, their efficacy is limited effectiveness and often associated with significant side effects. This underscores the urgent need to explore alternative, non-pharmacological interventions. Oxidative stress has been identified as a central player in AD pathology, influencing various aspects including amyloid-beta metabolism, tau phosphorylation, autophagy, neuroinflammation, mitochondrial dysfunction, and synaptic dysfunction. Among the emerging non-drug approaches, hydrogen therapy has garnered attention for its potential in mitigating these pathological conditions. This review provides a comprehensively overview of the therapeutic potential of hydrogen in AD. We delve into its mechanisms of action, administration routes, and discuss the current challenges and future prospects, with the aim of providing valuable insights to facilitate the clinical application of hydrogen-based therapies in AD management.

The effect of hydrogen-rich water on letrozole-induced polycystic ovary syndrome in rats

RESEARCH QUESTION

What is the effect of hydrogen-rich water on rats with polycystic ovary syndrome (PCOS)?

DESIGN

Female rats were divided into four groups, each consisting of eight animals. The control group received a carboxymethyl cellulose (CMC) solution, the molecular hydrogen (H2) group was given hydrogen-rich water and a CMC solution, the PCOS group was administered letrozole dissolved in a CMC solution and the PCOS + H2 group was given hydrogen-rich water and letrozole dissolved in a CMC solution. Blood and tissue samples were then collected, and biochemical and histopathological analyses were conducted on the samples.

RESULTS

The histopathological analysis showed a reduction in the number of cysts in the PCOS + H2 group compared with the PCOS group (P < 0.0001). Additionally, the malondialdehyde, cortisol and testosterone data revealed a significant decrease in the PCOS + H2 group compared with the PCOS group (P = 0.0458, P = 0.0003, P = 0.0041, respectively). The glutathione also showed a statistically significant increase in the PCOS + H2 group compared with the PCOS group (P = 0.0012).

CONCLUSION

The study findings demonstrate that hydrogen-rich water reduces the number of cysts and oxidative damage in rats with PCOS.

Reactive oxygen species (ROS) scavenging biomaterials for anti-inflammatory diseases: from mechanism to therapy

Inflammation is a fundamental defensive response to harmful stimuli, but the overactivation of inflammatory responses is associated with most human diseases. Reactive oxygen species (ROS) are a class of chemicals that are generated after the incomplete reduction of molecular oxygen. At moderate levels, ROS function as critical signaling molecules in the modulation of various physiological functions, including inflammatory responses. However, at excessive levels, ROS exert toxic effects and directly oxidize biological macromolecules, such as proteins, nucleic acids and lipids, further exacerbating the development of inflammatory responses and causing various inflammatory diseases. Therefore, designing and manufacturing biomaterials that scavenge ROS has emerged an important approach for restoring ROS homeostasis, limiting inflammatory responses and protecting the host against damage. This review systematically outlines the dynamic balance of ROS production and clearance under physiological conditions. We focus on the mechanisms by which ROS regulate cell signaling proteins and how these cell signaling proteins further affect inflammation. Furthermore, we discuss the use of potential and currently available-biomaterials that scavenge ROS, including agents that were engineered to reduce ROS levels by blocking ROS generation, directly chemically reacting with ROS, or catalytically accelerating ROS clearance, in the treatment of inflammatory diseases. Finally, we evaluate the challenges and prospects for the controlled production and material design of ROS scavenging biomaterials.

Therapeutic Potential of Hydrogen-Rich Water on Muscle Atrophy Caused by Immobilization in a Mouse Model

Skeletal muscle atrophy is associated with poor quality of life and disability. Thus, finding a new strategy for the prevention and treatment of skeletal muscle atrophy is very crucial. This study aimed to investigate the therapeutic potential of hydrogen-rich water (HRW) on muscle atrophy in a unilateral hind limb immobilization model. Thirty-six male Balb/C mice were divided into control (without immobilization), atrophy, and atrophy + hydrogen-rich water (HRW). Unilateral hind limb immobilization was induced using a splint for 7 days (atrophy) and removed for 10 days (recovery). At the end of each phase, gastrocnemius and soleus muscle weight, limb grip strength, skeletal muscle histopathology, muscle fiber size, cross-section area (CSA), serum troponin I and skeletal muscle IL-6, TNF-α and Malondialdehyde (MDA), and mRNA expression of NF-κB, BAX and Beclin-1 were evaluated. Muscle weight and limb grip strength in the H2-treated group were significantly improved during the atrophy phase, and this improvement continued during the recovery period. Treatment by HRW increased CSA and muscle fiber size and reduced muscle fibrosis, serum troponin I, IL-6, TNF-α and MDA which was more prominent in the atrophy phase. These data suggest that HRW could improve muscle atrophy in an immobilized condition and could be considered a new strategy during rehabilitation.

In vitro fermentation properties of magnesium hydride and related modulation effects on broiler cecal microbiome and metabolome

Magnesium hydride (MGH), a highly promising hydrogen-producing substance/additive for hydrogen production through its hydrolysis reaction, has the potential to enhance broiler production. However, before incorporating MGH as a hydrogen-producing additive in broiler feed, it is crucial to fully understand its impact on microbiota and metabolites. In vitro fermentation models provide a fast, reproducible, and direct assessment tool for microbiota metabolism and composition. This study aims to investigate the effects of MGH and coated-magnesium hydride (CMG) on fermentation characteristics, as well as the microbiota and metabolome in the culture of in vitro fermentation using cecal inocula from broilers. After 48 h of incubation, it was observed that the presence of MGH had a significant impact on various factors. Specifically, the content of N-NH3 decreased, while the total hydrogen gas and total SCFAs increased. Furthermore, the presence of MGH promoted the abundance of SCFA-producing bacteria such as Ruminococcus, Blautia, Coprobacillus, and Dysgonomonas. On the other hand, the presence of CMG led to an increase in the concentration of lactic acid, acetic acid, and valeric acid. Additionally, CMG affected the diversity of microbiota in the culture, resulting in an enrichment of the relative abundance of Firmicutes, as well as genera of Lactobacillus, Coprococcus, and Eubacterium. Conversely, the relative abundance of the phylum Proteobacteria and pathogenic bacteria Shigella decreased. Metabolome analysis revealed that MGH and CMG treatment caused significant changes in 21 co-regulated metabolites, primarily associated with lipid, amino acid, benzenoids, and organooxygen compounds. Importantly, joint correlation analysis revealed that MGH or CMG treatments had a direct impact on the microbiota, which in turn indirectly influenced metabolites in the culture. In summary, the results of this study suggested that both MGH and coated-MGH have similar yet distinct positive effects on the microbiota and metabolites of the broiler cecal in an in vitro fermentation model.

Antitumoral Activity of Molecular Hydrogen and Proton in the Treatment of Glioblastoma: An Atypical Pharmacology?

Antioxidants in cancer therapy have been a hot topic in the medical field for 20 years. Antioxidants are able to reduce the risk of cancer formation by neutralizing free radicals. Protons (H+) and molecular hydrogen (H2) interact in the cell and are essential in a wide variety of processes. The antioxidant, anti-inflammatory, and antiapoptotic effects of H2 have been studied in numerous experimental and clinical studies. Experimental data indicate that H2 is an antitumor agent in the treatment of glioblastoma (GBM). In vivo H2 inhalation could suppress the growth of GBM tumors, thereby extending the survival of mice with GBM. The sphere-forming ability of glioma cells was suppressed by hydrogen treatment. In addition, H2 treatment also suppressed the migration, invasion, and colony-forming ability of glioma cells. Proton therapy and proton beam radiotherapy offer some advantages over other modern conformal photon-based therapies when used in the treatment of central nervous system malignancies.

Evaluation of the safety and potential lipid-lowering effects of oral hydrogen-rich coral calcium (HRCC) capsules in patients with metabolic syndrome: a prospective case series study

Background

Metabolic syndrome is characterized by a cluster-like occurrence of conditions such as hypertension, hyperglycaemia, elevated low-density lipoprotein (LDL) cholesterol or triglycerides (TG) and high visceral fat. Metabolic syndrome is linked to the build-up of plaque within the artery, which leads to disorders of the circulatory, nervous and immune systems. A variety of treatments target the regulation of these conditions; nevertheless, they remain dominant risk factors for the development of type 2 diabetes (T2DM) and cardiovascular disease (CVD), which affect 26.9% of the US population. Management and intervention strategies for improving cholesterol and/or TG are worthwhile, and recent studies on hydrogen treatment are promising, particularly as molecular hydrogen is easily ingested. This study aimed to investigate the lipid-lowering effects and quality of life (QOL) improvement of hydrogen-rich coral calcium (HRCC) in patients with metabolic syndrome.

Methods

The patients, all Taiwanese, were randomly assigned to 3 different doses (low, medium, and high) of HRCC capsules. The primary outcome was the adverse effects/symptoms during this 4-week use of HRCC capsules. The secondary outcome was lipid profile changes. Complete blood count, inflammatory biomarkers, and QOL were also measured before and after the course of HRCC.

Results

Sixteen patients with metabolic syndrome completed this study (7 males, 9 females; mean age: 62 years; range: 32-80). No obvious adverse effects were recorded. Only changes in blood TG reached significance. The baseline TG value was 193.19 μL (SD = 107.44), which decreased to 151.75 μL (SD = 45.27) after 4 weeks of HRCC (p = 0.04). QOL showed no significant changes.

Conclusion

This study is the first human clinical trial evaluating HRCC capsules in patients with metabolic syndrome. Based on the safety and potential TG-lowering effects of short-term HRCC, further long-term investigations of HRCC are warranted.

Clinical trial registration

[ClinicalTrials.gov], identifier [NCT05196295].

Hydrogen Therapy and Its Future Prospects for Ameliorating COVID-19: Clinical Applications, Efficacy, and Modality

Molecular hydrogen is renowned as an odorless and colorless gas. The recommendations developed by China suggest that the inhalation of hydrogen molecules is currently advised in COVID-19 pneumonia treatment. The therapeutic effects of molecular hydrogens have been confirmed after numerous clinical trials and animal-model-based experiments, which have expounded that the low molecular weight of hydrogen enables it to easily diffuse and permeate through the cell membranes to produce a variety of biological impacts. A wide range of both chronic and acute inflammatory diseases, which may include sepsis, pancreatitis, respiratory disorders, autoimmune diseases, ischemia-reperfusion damages, etc. may be treated and prevented by using it. H₂ can primarily be inoculated through inhalation, by drinking water (which already contains H₂), or by administrating the injection of saline H₂ in the body. It may play a pivotal role as an antioxidant, in regulating the immune system, in anti-inflammatory activities (mitochondrial energy metabolism), and cell death (apoptosis, pyroptosis, and autophagy) by reducing the formation of excessive reactive O₂ species and modifying the transcription factors in the nuclei of the cells. However, the fundamental process of molecular hydrogen is still not entirely understood. Molecular hydrogen H₂ has a promising future in therapeutics based on its safety and possible usefulness. The current review emphasizes the antioxidative, anti-apoptotic, and anti-inflammatory effects of hydrogen molecules along with the underlying principle and fundamental mechanism involved, with a prime focus on the coronavirus disease of 2019 (COVID-19). This review will also provide strategies and recommendations for the therapeutic and medicinal applications of the hydrogen molecule.

Botulinum toxin type A activates protective autophagy by modulating endoplasmic reticulum stress in hypoxia/reoxygenation-treated endothelial cells

Botulinum toxin type A (BTXA) previously protected endothelial cells in free skin flaps from ischemia/reperfusion injury by inducing autophagy. Endoplasmic reticulum (ER) stress-autophagy activation may have a role in BTXA-antagonized ischemia/reperfusion damage in human dermal microvascular endothelial cells (HDMECs), however, this has yet to be proven. HDMECs were pretreated with BTXA at various concentrations for 12 h before being subjected to hypoxia and reoxygenation (H/R). Cell Count Kit 8 (CCK8) and Western blot (WB) data showed that H/R treatment significantly increased the expression of ER stress (GRP78, CHOP) and autophagy (LC3II/I, Beclin-1) proteins. The optimal BTXA pretreatment concentration was 1.6 U/mL, which resulted in the highest levels of cell survival and expression of ER stress and autophagy. Following pretreatment with 1.6 U/mL BTXA and the addition of the ER stress inducer Thapsigargin (Tg), the ER stress inhibitor 4-phenylbutyrate (4-PBA), and the inhibitor of autophagy Bafilomycin A1 (Baf A1), respectively, HDMECs were then subjected to H/R treatment. Cell survival and the percentage of ethynyldeoxyuridine-labeled cells in the BTXA pretreatment groups were reduced by the addition of Tg, 4-PBA, and Baf A1. While the expression of GRP78, CHOP, and LC3 was upregulated by Tg and Baf A1, it was downregulated by 4-PBA. The findings showed that ER stress produced by BTXA pretreatment triggers protective autophagy and protects HDMECs from H/R damage. There were no cytoprotective effects from either excessive activation or reduction of ER stress. Our results are consistent with the notion that autophagy and moderate ER stress are critical for cellular longevity and, consequently, functional integrity and may represent a potential therapeutic target.

Mast Cells as a Potential Target of Molecular Hydrogen in Regulating the Local Tissue Microenvironment

Knowledge of the biological effects of molecular hydrogen (H₂), hydrogen gas, is constantly advancing, giving a reason for the optimism in several healthcare practitioners regarding the management of multiple diseases, including socially significant ones (malignant neoplasms, diabetes mellitus, viral hepatitis, mental and behavioral disorders). However, mechanisms underlying the biological effects of H₂ are still being actively debated. In this review, we focus on mast cells as a potential target for H₂ at the specific tissue microenvironment level. H₂ regulates the processing of pro-inflammatory components of the mast cell secretome and their entry into the extracellular matrix; this can significantly affect the capacity of the integrated-buffer metabolism and the structure of the immune landscape of the local tissue microenvironment. The analysis performed highlights several potential mechanisms for developing the biological effects of H₂ and offers great opportunities for translating the obtained findings into clinical practice.

Molecular Hydrogen: an Emerging Therapeutic Medical Gas for Brain Disorders

Oxidative stress and neuroinflammation are the main physiopathological changes involved in the initiation and progression of various neurodegenerative disorders or brain injuries. Since the landmark finding reported in 2007 found that hydrogen reduced the levels of peroxynitrite anions and hydroxyl free radicals in ischemic stroke, molecular hydrogen's antioxidative and anti-inflammatory effects have aroused widespread interest. Due to its excellent antioxidant and anti-inflammatory properties, hydrogen therapy via different routes of administration exhibits great therapeutic potential for a wide range of brain disorders, including Alzheimer's disease, neonatal hypoxic-ischemic encephalopathy, depression, anxiety, traumatic brain injury, ischemic stroke, Parkinson's disease, and multiple sclerosis. This paper reviews the routes for hydrogen administration, the effects of hydrogen on the previously mentioned brain disorders, and the primary mechanism underlying hydrogen's neuroprotection. Finally, we discuss hydrogen therapy's remaining issues and challenges in brain disorders. We conclude that understanding the exact molecular target, finding novel routes, and determining the optimal dosage for hydrogen administration is critical for future studies and applications.

Therapeutic Inhalation of Hydrogen Gas for Alzheimer’s Disease Patients and Subsequent Long-Term Follow-Up as a Disease-Modifying Treatment: An Open Label Pilot Study

(1) Background: Alzheimer’s disease (AD) is a progressive and fatal neurodegenerative disorder. Hydrogen gas (H2) is a therapeutic medical gas with multiple functions such as anti-oxidant, anti-inflammation, anti-cell death, and the stimulation of energy metabolism. To develop a disease-modifying treatment for AD through multifactorial mechanisms, an open label pilot study on H2 treatment was conducted. (2) Methods: Eight patients with AD inhaled 3% H2 gas for one hour twice daily for 6 months and then followed for 1 year without inhaling H2 gas. The patients were clinically assessed using the Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog). To objectively assess the neuron integrity, diffusion tensor imaging (DTI) with advanced magnetic resonance imaging (MRI) was applied to neuron bundles passing through the hippocampus. (3) Results: The mean individual ADAS-cog change showed significant improvement after 6 months of H2 treatment (−4.1) vs. untreated patients (+2.6). As assessed by DTI, H2 treatment significantly improved the integrity of neurons passing through the hippocampus vs. the initial stage. The improvement by ADAS-cog and DTI assessments were maintained during the follow-up after 6 months (significantly) or 1 year (non-significantly). (4) Conclusions: This study suggests that H2 treatment not only relieves temporary symptoms, but also has disease-modifying effects, despite its limitations.

Molecular Hydrogen: From Molecular Effects to Stem Cells Management and Tissue Regeneration

It is known that molecular hydrogen is a relatively stable, ubiquitous gas that is a minor component of the atmosphere. At the same time, in recent decades molecular hydrogen has been shown to have diverse biological effects. By the end of 2022, more than 2000 articles have been published in the field of hydrogen medicine, many of which are original studies. Despite the existence of several review articles on the biology of molecular hydrogen, many aspects of the research direction remain unsystematic. Therefore, the purpose of this review was to systematize ideas about the nature, characteristics, and mechanisms of the influence of molecular hydrogen on various types of cells, including stem cells. The historical aspects of the discovery of the biological activity of molecular hydrogen are presented. The ways of administering molecular hydrogen into the body are described. The molecular, cellular, tissue, and systemic effects of hydrogen are also reviewed. Specifically, the effect of hydrogen on various types of cells, including stem cells, is addressed. The existing literature indicates that the molecular and cellular effects of hydrogen qualify it to be a potentially effective agent in regenerative medicine.