Protective effect of hydrogen-rich water on liver function of colorectal cancer patients treated with mFOLFOX6 chemotherapy

Molecular Hydrogen Therapy-A Review on Clinical Studies and Outcomes

With its antioxidant properties, hydrogen gas (H2) has been evaluated in vitro, in animal studies and in human studies for a broad range of therapeutic indications. A simple search of "hydrogen gas" in various medical databases resulted in more than 2000 publications related to hydrogen gas as a potential new drug substance. A parallel search in clinical trial registers also generated many hits, reflecting the diversity in ongoing clinical trials involving hydrogen therapy. This review aims to assess and discuss the current findings about hydrogen therapy in the 81 identified clinical trials and 64 scientific publications on human studies. Positive indications have been found in major disease areas including cardiovascular diseases, cancer, respiratory diseases, central nervous system disorders, infections and many more. The available administration methods, which can pose challenges due to hydrogens' explosive hazards and low solubility, as well as possible future innovative technologies to mitigate these challenges, have been reviewed. Finally, an elaboration to discuss the findings is included with the aim of addressing the following questions: will hydrogen gas be a new drug substance in future clinical practice? If so, what might be the administration form and the clinical indications?

Redox-Mechanisms of Molecular Hydrogen Promote Healthful Longevity

Age-related diseases represent the largest threat to public health. Aging is a degenerative, systemic, multifactorial and progressive process, coupled with progressive loss of function and eventually leading to high mortality rates. Excessive levels of both pro- and anti-oxidant species qualify as oxidative stress (OS) and result in damage to molecules and cells. OS plays a crucial role in the development of age-related diseases. In fact, damage due to oxidation depends strongly on the inherited or acquired defects of the redox-mediated enzymes. Molecular hydrogen (H2) has recently been reported to function as an anti-oxidant and anti-inflammatory agent for the treatment of several oxidative stress and aging-related diseases, including Alzheimer's, Parkinson's, cancer and osteoporosis. Additionally, H2 promotes healthy aging, increases the number of good germs in the intestine that produce more intestinal hydrogen and reduces oxidative stress through its anti-oxidant and anti-inflammatory activities. This review focuses on the therapeutic role of H2 in the treatment of neurological diseases. This review manuscript would be useful in knowing the role of H2 in the redox mechanisms for promoting healthful longevity.

Polysaccharide of Atractylodes macrocephala Koidz alleviate lipopolysaccharide-induced liver injury in goslings via the p53 and FOXO pathways

Lipopolysaccharide (LPS) can affect the immune system of geese by inducing liver injury. The polysaccharide of Atractylodes macrocephala Koidz (PAMK) have obvious immune-enhancing effects. Accordingly, this experiment investigated the effect of PAMK on LPS-induced liver injury in goslings. Two hundred 1-day-old goslings were randomly divided into the control group, LPS group, PAMK group, and PAMK+ LPS group, and the PAMK and PAMK+ LPS groups were fed the basal diet with 400 mg/kg PAMK, while the control and LPS groups were fed the basal diet. On D 21, 23, and 25 of the formal trial, the goslings in the LPS and PAMK+LPS groups were injected intraperitoneally with 2 mg/kg LPS, and goslings in the control and PAMK groups were injected intraperitoneally with the same amount of saline. Livers were collected on D 25. HE-stained sections showed that PAMK could effectively alleviate the LPS-induced indistinct hepatic cord structure, loss of cytoplasmic contents of hepatocytes, and dilatation of hepatic sinusoids. The biochemical parameters of liver tissues showed that PAMK could alleviate the LPS-induced upregulation of alanine aminotransferase and aspartate aminotransferase. To further investigate the mechanism of the mitigating effect of PAMK on LPS-induced injury, livers from the LPS and PAMK+LPS groups were selected for transcriptome sequencing. The sequencing results showed that there were 406 differentially expressed genes (DEGs) in the livers of LPS and PAMK+LPS goslings, of which 242 upregulated and 164 downregulated. The Kyoto Encyclopedia of Genes and Genome (KEGG) analysis showed that DEGs were significantly enriched in immune signal transduction, cell cycle, and cell metabolism. Besides, protein‒protein interaction analysis showed that 129 DEGs were associated with each other, including 7 DEGs enriched in the p53 and FOXO signaling pathway. In conclusion, PAMK may alleviate LPS-induced liver injury in gosling through the p53 and FOXO signaling pathway. These results provide a basis for further development of PAMK as an immunomodulator.

Polysaccharide of Atractylodes macrocephala Koidz alleviate lipopolysaccharide-stimulated liver inflammation injury of goslings through miR-223/NLRP3 axis

Lipopolysaccharide (LPS) infection could cause severe liver inflammation and lead to liver damage, even death. Previous studies have shown that polysaccharide of Atractylodes macrocephala Koidz (PAMK) could protect liver from inflammation caused by LPS in mice. However, whether PAMK could alleviate liver inflammatory injury in other animals with LPS is still unknown. For evaluating whether PAMK could alleviate liver inflammatory injury in goslings with LPS, a total of 80 healthy 1-day old Magang goslings were randomly divided into 4 groups (control group, PAMK group, LPS group, and PAMK+LPS group). Goslings in control group and LPS group were fed with basal diet, and goslings in PAMK group and PAMK+LPS group were fed basal diet supplemented with 400 mg/kg PAMK to the end of trial. On 24 d of age, goslings in the control group and PAMK group were intraperitoneal injected 0.5 mL normal saline, and goslings in LPS and PAMK+LPS groups were intraperitoneal injected with LPS at 5 mg/kg BW. The serum and liver samples were collected for further analysis after treatment of LPS at 6, 12, 24, and 48 h. Furthermore, the hepatocytes were extracted from goose embryo to measure the expression of the key genes of miR-223/NLRP3 axis. The results showed that PAMK pretreatment could maintain normal cell morphology of liver, alleviate the enhanced levels of biochemical indexes ALT and AST, decrease the levels of IL-1β and IL-18, increase the relative mRNA expression of miR-223, and decrease the expression of NLRP3, Caspase-1, and cleaved Caspase-1 in liver and hepatocytes of goslings induced by LPS. These results indicated that PAMK could relieve inflammatory liver tissue damage after LPS treatment and downregulate the level of inflammation factors via miR-223/NLRP3 axis, thus playing a liver protective role in liver inflammation injury in goslings.

Effects of Long-Term Low-Protein Diets Supplemented with Sodium Dichloroacetate and Glucose on Metabolic Biomarkers and Intestinal Microbiota of Finishing Pigs

The objective of this study was to evaluate the effects of low-protein (LP) diets supplemented with sodium dichloroacetate (DCA) and glucose (GLUC) on metabolic markers and intestinal microbiota of finishing pigs. A total of 80 crossbred growing barrows were allocated randomly to one of the five treatments, including the normal protein level diet (CON), the LP diets, LP with 120 mg/kg DCA (LP + DCA) or 1.8% glucose (LP + GLUC), and LP with 120 mg/kg DCA and 1.8% glucose (LP + DCA + GLUC). The LP diet increased the plasma HDL, triglyceride, and cholesterol concentrations and reduced the bile acid, urea nitrogen, albumin, and total protein concentrations compared to the CON diet (p < 0.05). The LP + DCA + GLUC diet reduced the plasma VLDL, triglyceride, and cholesterol concentrations and increased the bile acid concentration compared with the LP diet (p < 0.05). Pigs fed the LP + DCA and LP + GLUC diets showed reduced 3-Hydroxy-3-Methylglutaryl-CoA Reductase content and increased Cytochrome P450 Family 7 Subfamily A Member 1 activity of liver compared that of the CON diet (p < 0.05). Moreover, the LP diets with or without DCA and GLUC supplementation increased the relative abundance of colonic microbiota related to carbohydrate fermentation in finishing pigs. In conclusion, 120 mg/kg DCA or 1.8% GLUC supplementation in an LP diet modulated the hepatic lipid metabolism of pigs, while the DCA along with GLUC supplementation likely improved the lipid metabolism by stimulating bile acid secretion.

Molecular Hydrogen Enhances Proliferation of Cancer Cells That Exhibit Potent Mitochondrial Unfolded Protein Response

Molecular hydrogen ameliorates pathological states in a variety of human diseases, animal models, and cell models, but the effects of hydrogen on cancer have been rarely reported. In addition, the molecular mechanisms underlying the effects of hydrogen remain mostly unelucidated. We found that hydrogen enhances proliferation of four out of seven human cancer cell lines (the responders). The proliferation-promoting effects were not correlated with basal levels of cellular reactive oxygen species. Expression profiling of the seven cells showed that the responders have higher gene expression of mitochondrial electron transport chain (ETC) molecules than the non-responders. In addition, the responders have higher mitochondrial mass, higher mitochondrial superoxide, higher mitochondrial membrane potential, and higher mitochondrial spare respiratory capacity than the non-responders. In the responders, hydrogen provoked mitochondrial unfolded protein response (mtUPR). Suppression of cell proliferation by rotenone, an inhibitor of mitochondrial ETC complex I, was rescued by hydrogen in the responders. Hydrogen triggers mtUPR and induces cell proliferation in cancer cells that have high basal and spare mitochondrial ETC activities.

Hydrogen-rich water exerts anti-tumor effects comparable to 5-fluorouracil in a colorectal cancer xenograft model

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the world. Tumor removal remains the preferred frontline treatment; however, effective non-surgical interventions remain a high priority. 5-fluorouracil (5-FU) is a widely used chemotherapy agent, and molecular hydrogen (H₂) has been recognized for its antioxidant and anti-inflammatory effects, with research also suggesting its potential anti-tumor effects. Therefore, H₂ dissolved in water [hydrogen-rich water (HRW)], with or without 5-FU, may present itself as a novel therapeutic for CRC.

AIM

To investigate the effects of HRW, with or without 5-FU, as a novel therapeutic for CRC.

METHODS

CRC was induced in the left flank of inbred Balb/c mice. A total of 24 mice bearing tumors were randomly divided into four groups (n = 6 per group) and treated as follows: (1) Control group; (2) 5-FU group that received intraperitoneal injection of 5-FU (5 mg/kg) every other day; (3) H₂ group that received HRW, created and delivered via dissolving the H₂-generating tablet in the animals’ drinking water, with 200 μL also delivered by oral gavage; and (4) The combination group, H₂ (administered in same way as for group three) combined with 5-FU administered same way as group two.

RESULTS

Administration of HRW + 5-FU significantly improved tumor weight, tumor size, collagen content and fibrosis as compared to the CRC control group. Specifically, HRW attenuated oxidative stress (OS) and potentiated antioxidant activity (AA), whereas 5-FU treatment exacerbated OS and blunted AA. The combination of HRW + 5-FU significantly reduced tumor weight and size, as well as reduced collagen deposition and the degree of fibrosis, while further increasing OS and decreasing AA compared to administration of 5-FU alone.

CONCLUSION

Administration of HRW, with or without 5-FU, may serve as a therapeutic for treating CRC.

Drinking Molecular Hydrogen Water Is Beneficial to Cardiovascular Function in Diet-Induced Obesity Mice

Molecular hydrogen (MH) reportedly exerts therapeutic effects against inflammatory diseases as a suppressor of free radical chain reactions. Here, the cardiovascular protective effects of the intake of molecular hydrogen water (MHW) were investigated using high-fat diet-induced obesity (DIO) mice. MHW was prepared using supplier sticks and degassed water as control. MHW intake for 2 weeks did not improve blood sugar or body weight but decreased heart weight in DIO mice. Moreover, MHW intake improved cardiac hypertrophy, shortened the width of cardiomyocytes, dilated the capillaries and arterioles, activated myocardial eNOS-Ser-1177 phosphorylation, and restored left ventricular function in DIO mice. MHW intake promoted the histological conversion of hypertrophy to hyperplasia in white and brown adipose tissues (WAT and BAT) with the upregulation of thermogenic and cardiovascular protective genes in BAT (i.e., Ucp-1, Vegf-a, and eNos). Furthermore, the results of a colony formation assay of bone-marrow-derived endothelial progenitor cells (EPCs) indicated that MHW activated the expansion, differentiation, and mobilization of EPCs to maintain vascular homeostasis. These findings indicate that the intake of MHW exerts cardiovascular protective effects in DIO mice. Hence, drinking MHW is a potential prophylactic strategy against cardiovascular disorders in metabolic syndrome.

Hydrogen: An Endogenous Regulator of Liver Homeostasis

Basic and clinical studies have shown that hydrogen (H₂), the lightest gas in the air, has significant biological effects of anti-oxidation, anti-inflammation, and anti-apoptosis. The mammalian cells have no abilities to produce H₂ due to lack of the expression of hydrogenase. The endogenous H₂ in human body is mainly produced by anaerobic bacteria, such as Firmicutes and Bacteroides, in gut and other organs through the reversible oxidation reaction of 2 H⁺ + 2 e^- ⇌ H₂. Supplement of exogenous H₂ can improve many kinds of liver injuries, modulate glucose and lipids metabolism in animal models or in human beings. Moreover, hepatic glycogen has strong ability to accumulate H₂, thus, among the organs examined, liver has the highest concentration of H₂ after supplement of exogenous H₂ by various strategies in vivo. The inadequate production of endogenous H₂ play essential roles in brain, heart, and liver disorders, while enhanced endogenous H₂ production may improve hepatitis, hepatic ischemia and reperfusion injury, liver regeneration, and hepatic steatosis. Therefore, the endogenous H₂ may play essential roles in maintaining liver homeostasis.

Hydrogen Gas in Cancer Treatment

Gas signaling molecules (GSMs), composed of oxygen, carbon monoxide, nitric oxide, hydrogen sulfide, etc., play critical roles in regulating signal transduction and cellular homeostasis. Interestingly, through various administrations, these molecules also exhibit potential in cancer treatment. Recently, hydrogen gas (formula: H₂) emerges as another GSM which possesses multiple bioactivities, including anti-inflammation, anti-reactive oxygen species, and anti-cancer. Growing evidence has shown that hydrogen gas can either alleviate the side effects caused by conventional chemotherapeutics, or suppress the growth of cancer cells and xenograft tumor, suggesting its broad potent application in clinical therapy. In the current review, we summarize these studies and discuss the underlying mechanisms. The application of hydrogen gas in cancer treatment is still in its nascent stage, further mechanistic study and the development of portable instruments are warranted.

Molecular hydrogen suppresses glioblastoma growth via inducing the glioma stem-like cell differentiation

Background

Glioblastoma (GBM) is the most common type of primary malignant brain tumor. Molecular hydrogen has been considered a preventive and therapeutic medical gas in many diseases including cancer. In our study, we sought to assess the potential role of molecular hydrogen on GBM.

Methods

The in vivo studies were performed using a rat orthotopic glioma model and a mouse subcutaneous xenograft model. Animals inhaled hydrogen gas (67%) 1 h two times per day. MR imaging studies were performed to determine the tumor volume. Immunohistochemistry (IHC), immunofluorescence staining, and flow cytometry analysis were conducted to determine the expression of surface markers. Sphere formation assay was performed to assess the cancer stem cell self-renewal capacity. Assays for cell migration, invasion, and colony formation were conducted.

Results

The in vivo study showed that hydrogen inhalation could effectively suppress GBM tumor growth and prolong the survival of mice with GBM. IHC and immunofluorescence staining demonstrated that hydrogen treatment markedly downregulated the expression of markers involved in stemness (CD133, Nestin), proliferation (ki67), and angiogenesis (CD34) and also upregulated GFAP expression, a marker of differentiation. Similar results were obtained in the in vitro studies. The sphere-forming ability of glioma cells was also suppressed by hydrogen treatment. Moreover, hydrogen treatment also suppressed the migration, invasion, and colony-forming ability of glioma cells.

Conclusions

Together, these results indicated that molecular hydrogen may serve as a potential anti-tumor agent in the treatment of GBM.

Sirt3 mediates the protective effect of hydrogen in inhibiting ROS-induced retinal senescence

Hydrogen possesses antioxidative effects and cures numerous types of ophthalmopathy, but the mechanism of hydrogen on ROS-induced retinal senescence remains elusive. In this study, retinal morphology revealed that hydrogen reduced the number and size of vitreous black deposits in Bruch's membrane in NaIO3 mice. Hydrogen also reduced ROS levels in the retina as assessed by DHE staining. Moreover, this result was consistent with the downregulation of expression of the oxidative stress hallmark OGG1. These findings suggested that hydrogen can reduce retinal oxidative stress induced by NaIO3, and this result was further verified using the antioxidant ALCAR. Mechanistic analysis revealed that hydrogen significantly inhibited the downregulation of Sirt3 expression, and this notion was confirmed using AICAR, which restores Sirt3 expression and activity. Moreover, hydrogen reduced the expression of p53, p21 and p16 and the number of blue-green precipitations in the retinas of NaIO3 mice as assessed by SA-β-gal staining. We also found that hydrogen decreased the expression of the DNA damage-related protein ATM, cyclinD1 and NF-κB but increased the expression of the DNA repair-related protein HMGB1, suggesting that hydrogen inhibits senescence in retinas of NaIO3 mice. Additionally, OCT examination revealed that hydrogen suppressed retinal high reflex formation significantly and prevented the retina from thinning. This result was supported by ERG assays that demonstrated that hydrogen prevented the reduction in a- and b-wave amplitude induced by NaIO3 in mice. Thus, our data suggest that hydrogen may inhibit retinal senescence by suppressing the downregulation of Sirt3 expression through reduced oxidative stress reactions.