Inhibitory effect of electrolyzed reduced water on tumor angiogenesis

Electrolyzed-Reduced Water: Review I. Molecular Hydrogen Is the Exclusive Agent Responsible for the Therapeutic Effects

Numerous benefits have been attributed to alkaline-electrolyzed-reduced water (ERW). Sometimes these claims are associated with easily debunked concepts. The observed benefits have been conjectured to be due to the intrinsic properties of ERW (e.g., negative oxidation-reduction potential (ORP), alkaline pH, H₂ gas), as well enigmatic characteristics (e.g., altered water structure, microclusters, free electrons, active hydrogen, mineral hydrides). The associated pseudoscientific marketing has contributed to the reluctance of mainstream science to accept ERW as having biological effects. Finally, through many in vitro and in vivo studies, each one of these propositions was examined and refuted one-by-one until it was conclusively demonstrated that H₂ was the exclusive agent responsible for both the negative ORP and the observed therapeutic effects of ERW. This article briefly apprised the history of ERW and comprehensively reviewed the sequential research demonstrating the importance of H₂. We illustrated that the effects of ERW could be readily explained by the known biological effects of H₂ and by utilizing conventional chemistry without requiring any metaphysical conjecture (e.g., microclustering, free electrons, etc.) or reliance on implausible notions (e.g., alkaline water neutralizes acidic waste). The H₂ concentration of ERW should be measured to ensure it is comparable to those used in clinical studies.

Electrolyzed-Reduced Water: Review II: Safety Concerns and Effectiveness as a Source of Hydrogen Water

Many studies demonstrate the safety of alkaline-electrolyzed-reduced water (ERW); however, several animal studies have reported significant tissue damage and hyperkalemia after drinking ERW. The mechanism responsible for these results remains unknown but may be due to electrode degradation associated with the production of higher pH, in which platinum nanoparticles and other metals that have harmful effects may leach into the water. Clinical studies have reported that, when ERW exceeds pH 9.8, some people develop dangerous hyperkalemia. Accordingly, regulations on ERW mandate that the pH of ERW should not exceed 9.8. It is recommended that those with impaired kidney function refrain from using ERW without medical supervision. Other potential safety concerns include impaired growth, reduced mineral, vitamin, and nutrient absorption, harmful bacterial overgrowth, and damage to the mucosal lining causing excessive thirst. Since the concentration of H2 in ERW may be well below therapeutic levels, users are encouraged to frequently measure the H2 concentration with accurate methods, avoiding ORP or ORP-based H2 meters. Importantly, although, there have been many people that have used high-pH ERW without any issues, additional safety research on ERW is warranted, and ERW users should follow recommendations to not ingest ERW above 9.8 pH.

Effect of Functional Water on the Antioxidant Property of Concentrated Reconstituted Juice

People often consume juice to easily ingest antioxidants, which can scavenge free radicals and reduce the risk of lifestyle-related diseases. In this study, the SOD assay kit-WST method was used to evaluate the antioxidant activity of two types of functional water, alkaline electrolyzed water (AlEW) and tourmaline water (TMW), reconstituted commercially available (Tropicana) and freshly squeezed concentrated juices and the effect of functional waters on physicochemical parameters and sensory evaluation of reconstituted juices was also analyzed. The reconstituted juice exhibited the highest antioxidant activity when the electrolysis current of AlEW was 8A or the tourmaline stone treatment temperature of TMW was 75 °C. Compared with the control group (69.4%), SOD activity of the reconstituted orange juice in the 8A-AlEW (77.2%) and 75 °C-TMW (84.5%) groups increased by 7.8 and 15.1%, respectively. Furthermore, the color and pH of the functional water reconstituted juice were not significantly different from the juice before concentration, and the taste was better. In summary, functional water could enhance the antioxidant activity of concentrated juice as a formula which could provide novel ideas for the development of functional beverages with antioxidant properties.

Natural COA water inhibits mitochondrial ROS-mediated apoptosis through Plk3 downregulation under STZ diabetic stress in pancreatic β-cell lines

Diabetes from pancreatic β cell death and insulin resistance is a serious metabolic disease in the world. Although the overproduction of mitochondrial reactive oxygen species (ROS) plays an important role in the pathogenesis of diabetes, its specific molecular mechanism remains unclear. Here, we show that the natural Charisma of Aqua (COA) water plays a role in Streptozotocin (STZ) diabetic stress-induced cell death inhibition. STZ induces mitochondrial ROS by increasing Polo-like kinase 3 (Plk3), a major mitotic regulator, in both Beta TC-6 and Beta TC-tet mouse islet cells and leads to apoptosis. Overexpression of Plk3 regulates an increase in mitochondrial ROS as well as cell death, also these events were inhibited by Plk3 gene knockdown in STZ diabetic stimulated-Beta TC-6 cells. Interestingly, we found that natural COA water blocks mitochondrial ROS generation through the reduction of Plk3 and prevents apoptosis in STZ-treated beta cells. Furthermore, using the 3D organoid (ex vivo) system, we confirmed that the insulin secretion of the supernatant medium under STZ treated pancreatic β-cells is protected by the natural COA water. These findings demonstrate that the natural water COA has a beneficial role in maintaining β cell function through the inhibition of mitochondrial ROS-mediated cell death, and it might be introduced as a potential insulin stabilizer.

•

Pancreatic β cell is stabilized through natural COA water in STZ-induced diabetes.

•

Mitochondrial membrane potential (ΔΨm) is controlled by natural COA water.

•

Plk3 expression under STZ treatment is negatively regulated by natural COA water.

•

Insulin secretion is stabilized by natural COA water under STZ treatment in ex vivo (3D organoid) model.

Electrolyzed Water and Its Pharmacological Activities: A Mini-Review

Electrolyzed water (EW) is a new type of cleaning and disinfecting agent obtained by means of electrolysis with a dilute sodium chloride solution. It has low cost and harm to the human body and is also friendly to the environment. The anode produces acidic electrolyzed water (AEW), which is mainly used to inhibit bacterial growth and disinfect. The cathode provides basic electrolyzed water (BEW), which is implemented to promote human health. EW is a powerful multifunctional antibacterial agent with a wide range of applications in the medicine, agriculture, and food industry. Studies in vitro and in vivo show that it has an inhibitory effect on pathogenic bacteria and viruses. Therefore, EW is used to prevent chronic diseases, while it has been found to be effective against various kinds of infectious viruses. Animal experiments and clinical trials clearly showed that it accelerates wound healing, and has positive effects in oral health care, anti-obesity, lowering blood sugar, anti-cancer and anti-infectious viral diseases. This review article summarizes the application of EW in treating bacteria and viruses, the prevention of chronic diseases, and health promotion.

A new colorimetric method for determining antioxidant levels using 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS)

We describe here a novel assay that determines the total a+ntioxidative activities of known antioxidants and antioxidants in beverages. The method employs the substrate 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) that yields the colored product 3,5,3’,5’-tetrabromoazobenzene sulfate sodium salt (azo-TBBS). The amounts of azo-TBBS are measured using HPLC and then used to calculate total antioxidative capacity (TAC) values. We first show that the TAC values measured using the new DBNBS system were significantly higher compared with the control. The assay was validated through further analysis of 56 compounds, including previously characterized antioxidants. The data are consistent with published values. Here we describe in detail the application of the DBNBS method to the measurement of the TAC values of eight beverages, including wines and fruit juices. The DBNBS assay employs a readily applicable protocol that sensitively determines the levels of antioxidants in foodstuffs.

- A new DBNBS-mediated antioxidant assay system is compared with standard DPPH and ORAC assays

- DBNBS traps hydrogen radicals to generate a readily measured colored reduction product that quantifies antioxidant levels

The Search for the Elixir of Life: On the Therapeutic Potential of Alkaline Reduced Water in Metabolic Syndromes

Our body composition is enormously influenced by our lifestyle choices, which affect our health and longevity. Nutrition and physical activities both impact overall metabolic condition, thus, a positive energy balance causes oxidative stress and inflammation, hastening the development of metabolic syndrome. With this knowledge, boosting endogenous and exogenous antioxidants has emerged as a therapeutic strategy for combating metabolic disorders. One of the promising therapeutic inventions is the use of alkaline reduced water (ARW). Aside from its hydrating and non-caloric properties, ARW has demonstrated strong antioxidant and anti-inflammatory properties that can help stabilize physiologic turmoil caused by oxidative stress and inflammation. This review article is a synthesis of studies where we elaborate on the intra- and extracellular effects of drinking ARW, and relate these to the pathophysiology of common metabolic disorders, such as obesity, diabetes mellitus, non-alcoholic fatty liver disease, and some cancers. Highlighting the health-promoting benefits of ARW, we also emphasize the importance of maintaining a healthy lifestyle by incorporating exercise and practicing a balanced diet as forms of habit.

The Preventive Role of Hydrogen-Rich Water in Thioacetamide-Induced Cholangiofibrosis in Rat Assessed by Automated Histological Classification

Background: Cholangiofibrosis is a controversial intrahepatic cholangial lesion that precedes the development of cholangiocarcinoma. Here, we demonstrate that molecular hydrogen (H₂) can be used to effectively prevent cholangiofibrosis.

Methods: The safety and quality of life (QOL) of rats was firstly evaluated. H₂ was administered to rats subjected to thioacetamide (TAA)-induced cholangiofibrosis throughout the whole process. Then, rats were administrated with TAA for 3 months and then followed by H₂ intervention. Rat livers were harvested and assessed by light microscopy and convolutional neural network. RNA-seq was performed to analyze the genetic changes in these animal models.

Results: Continuous use of H₂-rich water was safe and improved QOL.The incidence and average number of cholangiofibrosis in the liver were higher in the TAA group (100%, 12.0 ± 10.07) than that in the H₂ group (57.1%, 2.86 ± 5.43). The AI algorithm revealed higher Alesion/Aliver in the TAA group (19.6% ± 9.01) than that in the H₂ group (7.54% ± 11.0). RNA-seq analysis revealed that H₂ results in a decline in glycolysis. Moreover, in the third experiment, the incidence of microscopic or suspicious tumors and the ratio of liver lesions was decreased after long-term use of H₂ (12.5%, 0.57% ± 0.45) compared with untreated group (100%, 0.98% ± 0.73). A number of intestinal microbiota was changed after H₂ usage, including clostridiaceae_1, ruminococcus, turicibacter, coriobacteriales, actinobacteria, and firmicutes_bacterium.

Conclusion: Hydrogen-rich water protects against liver injury and cholangiofibrosis and improved quality of life partially through regulating the composition of intestinal flora.

Molecular Hydrogen as a Novel Antitumor Agent: Possible Mechanisms Underlying Gene Expression

While many antitumor drugs have yielded unsatisfactory therapeutic results, drugs are one of the most prevalent therapeutic measures for the treatment of cancer. The development of cancer largely results from mutations in nuclear DNA, as well as from those in mitochondrial DNA (mtDNA). Molecular hydrogen (H₂), an inert molecule, can scavenge hydroxyl radicals (·OH), which are known to be the strongest oxidizing reactive oxygen species (ROS) in the body that causes these DNA mutations. It has been reported that H₂ has no side effects, unlike conventional antitumor drugs, and that it is effective against many diseases caused by oxidative stress and chronic inflammation. Recently, there has been an increasing number of papers on the efficacy of H₂ against cancer and its effects in mitigating the side effects of cancer treatment. In this review, we demonstrate the efficacy and safety of H₂ as a novel antitumor agent and show that its mechanisms may not only involve the direct scavenging of ·OH, but also other indirect biological defense mechanisms via the regulation of gene expression.

Electrolyzed Hydrogen Water Protects against Ethanol-Induced Cytotoxicity by Regulating Aldehyde Metabolism-Associated Enzymes in the Hepatic Cell Line HepG2

Excessive alcohol consumption can cause multi-systemic diseases. Among them, alcoholic liver disease is the most frequent and serious disease. Electrolytic hydrogen water (EHW) is produced at the cathode during electrolysis of water and contains a large amount of molecular hydrogen and a low content of platinum nanoparticles with alkaline properties. In this study, we found that EHW inhibits ethanol-induced cytotoxicity by decreasing the intracellular acetaldehyde, a toxic substance produced by ethanol degradation, in hepatocyte cell lines HepG2. Analysis of the mechanism of action revealed that EHW inhibits the metabolism of ethanol to acetaldehyde by suppressing alcohol dehydrogenase. EHW also promotes the metabolism of acetaldehyde to acetic acid by activating aldehyde dehydrogenase, which plays to reduce aldehyde toxicity and intracellular reactive oxygen species in HepG2 cells. These functions were correlated with the concentration of molecular hydrogen in EHW, and were abolished by degassing treatment, suggesting that molecular hydrogen may contribute as a functional factor in the suppression of ethanol-induced hepatocellular damage. Furthermore, hydrogen water with high dissolved hydrogen molecule showed the same hepatocellular protective effect against ethanol as the EHW. These results suggest that EHW may be useful in the prevention of alcoholic liver disease.

Effects of Topical Hydrogen Purification on Skin Parameters and Acne Vulgaris in Adult Women

BACKGROUND

Acne vulgaris is a prevalent dermatological disease characterized by skin eruptions, which may decrease the sufferer's quality of life. Hydrogen purification treatment is a new procedure used in cosmetology to improve the skin parameters of the face. This study examined the effectiveness of hydrogen purification treatment to improve women's skin conditions with regard to acne vulgaris.

METHODS

In this study, 30 women participated who suffered from a high level of sebum and acne. The control group was comprised of 30 healthy women with a low level of sebum. The Hellgren-Vincent Scale and Derma Unit SSC 3 device were used to assess acne vulgaris severity and skin properties, respectively. Four hydrogen purification sessions were carried out at 7-day intervals, using the Hebe Hydrogenium+ generating alkaline water.

RESULTS

At baseline and 7 and 14 days after finishing the series of treatments, the levels of oiliness, moisture, and skin pH were tested. The main effects of treatment were significant in the following parameters: pH around the bottom lip, moisture between the eyebrows and around the nose, and oily skin in all three face sites.

CONCLUSIONS

The level of sebum decreased and moisture levels increased during hydrogen purification. Topical hydrogen purification is an effective and safe treatment for acne vulgaris.

Molecular Mechanism and Approach in Progression of Meningioma

Meningioma is the most common tumor of the central nervous system, most of which is benign. Even after complete resection, a high rate of recurrence of meningioma is observed. From in-depth study of its pathogenesis, it has been found that a number of chromosomal variations and abnormal molecular signals are closely related to the occurrence and development of malignancy in meningioma, which may provide the theoretical basis and potential direction for accurate and targeted treatment. We have reviewed advances in chromosomal variations and molecular mechanisms involved in the progression of meningioma, and have highlighted the association with malignant biological behavior including cell proliferation, angiogenesis, increased invasiveness, and inhibition of apoptosis. In addition, the chemotherapy of meningioma is summarized and discussed.

Outcomes Assessment of Sustainable and Innovatively Simple Lifestyle Modification at the Workplace - Drinking Electrolyzed-Reduced Water (OASIS-ERW): A Randomized, Double-Blind, Placebo-Controlled Trial

Oxidative stress has been associated with many diseases as well as aging. Electrolyzed-reduced water (ERW) has been suggested to reduce oxidative stress and improve antioxidant potential. This study investigated the effects of drinking ERW on biomarkers of oxidative stress and health-related indices in healthy adults. We conducted a randomized, double-blind, placebo-controlled clinical trial on 65 participants, who were allocated into two groups. Of these, 61 received intervention (32 with ERW and 29 MW [mineral water]). All participants were instructed to drink 1.5 L/day of ERW or MW for eight weeks. Biomarkers of oxidative stress and health-related indices were assessed at baseline as well as after 4 weeks and 8 weeks of intervention. Of the primary outcome variables assessed, diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential showed a significant interaction between the groups and time, with d-ROMs levels significantly decreased at 8 weeks in ERW compared to those in MW. Among the secondary outcome variables, total, visceral, and subcutaneous fat mass significantly changed over time, with a significant association observed between the groups and time. Thus, daily ERW consumption may be a potential consideration for a sustainable and innovatively simple lifestyle modification at the workplace to reduce oxidative stress, increase antioxidant potential, and decrease fat mass.

Monolayered Platinum Nanoparticles as Efficient Electrocatalysts for the Mass Production of Electrolyzed Hydrogen Water

High-performance/low-cost platinum (Pt)-based electrocatalysts have been established by top-coating both sides of a titanium plate with Pt nanoparticles. The average diameter of the Pt nanoparticles used in this study is approximately 100 nm. Three types of Pt top-coated Pt/Ti electrocatalysts, each having different top-coated Pt layer thicknesses, are prepared. Type I is a monolayered Pt top-coated type, in which the thickness of the top-coated Pt layer is approximately 100 nm; Type II is a few-layered type with a top-coated Pt layer thickness of approximately 200 nm, and Type III is a multilayered type with a top-coated Pt layer thickness of approximately 750 nm. The mass loading of Pt is 0.0215 mg cm⁻² for Type I, 0.043 mg cm⁻² for Type II, and 0.161 mg cm⁻² for Type III. The electrocatalytic activities of each type of Pt/Ti electrocatalyst are evaluated through the electrolysis of acidic water and tap water. Type I gives the highest electrocatalytic efficiencies, which are comparable or even better than the electrocatalytic efficiencies of the state-of-the-art commercially available Pt/C electrode and other metal-/carbon-based HER catalysts. For example, in the case of the electrolysis of acidic water at an overpotential of 0.15 V, Type I shows a Tafel slope of 29 mV dec⁻¹ and a current density of 27.5 mA cm⁻². Even in the case of the electrolysis of tap water, Type I gives an HER Faradaic efficiency of 92%. A model of water (H₂O), hydronium ions (H₃O⁺), and hydroxyl ions (OH⁻) properly adsorbing on the Pt (111) facet is proposed to explain the electrocatalytic mechanism. New insights into the distinguishing properties of the resultant electrolyzed hydrogen water (EHW), namely, the healthy beneficial effects of EHW, are also described, and a new concept of storing and carrying reductive hydrogen (H*) by free Pt nanoparticles is proposed.

Long-Term Potable Effects of Alkalescent Mineral Water on Intestinal Microbiota Shift and Physical Conditioning

BACKGROUND

An alkalescent (pH 8.3) mineral water (AMW) of Hita basin, located in the northwestern part of Kyushu island in Japan, has been recognized for the unique quality of ingredients including highly concentrated silicic acid, sodium, potassium, and hydrogen carbonate. The biological effects of AMW intake were evaluated with a particular focus on its "antiobesity" properties through its modulation of the gut microbiota population.

METHODS

Two groups of C57BL6/J mice (8-week-old male) were maintained with a standard diet and tap water (control: TWC group) or AMW (AMW group) for 6 months and the following outputs were quantitated: (1) food and water intake, (2) body weight (weekly), (3) body fat measurements by CT scan (monthly), (4) sera biochemical values (TG, ALT, AST, and ALP), and (5) UCP-1 mRNA in fat tissues (terminal point). Two groups of ICR mice (7-week-old male) were maintained with the same method and their feces were collected at the 0, 1st, 3rd, and 6th month at which time the population rates of gut microbiota were quantitated using metagenomic sequencing analysis of 16S-rRNA.

RESULTS

Among all antiobesity testing items, even though a weekly dietary consumption was increased (p=0.012), both ratios of weight gain (p=1.21E - 10) and visceral fat accumulation (p=0.029) were significantly reduced in the AMW group. Other criteria including water intake (p=0.727), the amounts of total (p=0.1602), and subcutaneous fat accumulation (p=0.052) were within the margin of error and UCP-1 gene expression level (p=0.171) in the AMW group was 3.89-fold higher than that of TWC. Among 8 major gut bacteria families, Lactobacillaceae (increased, p=0.029) and Clostridiaceae (decreased, p=0.029) showed significant shift in the whole population.

CONCLUSION

We observed significantly reduced (1) weight gaining ratio (average -1.86%, up to -3.3%), (2) visceral fat accumulation ratio (average -4.30%, up to -9.1%), and (3) changes in gut microbiota population. All these consequences could support the "health benefit" functionality of AMW.

Micro/Nanomaterials-Augmented Hydrogen Therapy

Hydrogen therapy is an emerging and promising therapy strategy of using molecular hydrogen as a new type of safe and effective therapeutic agent, exhibiting remarkable therapeutic effects on many oxidative stress-/inflammation-related diseases owing to its bio-reductivity and homeostatic regulation ability. Different from other gaseous transmitters such as NO, CO, and H₂ S, hydrogen gas has no blood poisoning risk at high concentration because it does not affect the oxygen-carrying behavior of blood red cells. Hydrogen molecules also have low aqueous solubility and high but aimless diffusibility, causing limited therapy efficacy in many diseases. To realize the site-specific hydrogen delivery, controlled hydrogen release and combined therapy is significant but still challenging. Here, a concept of hydrogen nanomedicine to address the issues of hydrogen medicine by using functional micro/nanomaterials for augmented hydrogen therapy is proposed. In this review, various strategies of micro/nanomaterials-augmented hydrogen therapy, including micro/nanomaterials-mediated targeted hydrogen delivery, controlled hydrogen release, and nanocatalytic and multimodel enhancement of hydrogen therapy efficacy, are summarized, which can open a new window for treatment of inflammation-related diseases.

Efficacy of newly developed denture cleaning device on physical properties of denture material and Candida biofilm

Background/purpose

Electrolyzed water has antimicrobial activity against oral microbes. The purpose of this study was to investigate the effects of a denture cleaning device that uses electrolyzed water on Candida biofilm on denture base-material and the physical properties of the denture material.

Materials and methods

Denture base-resin disks were prepared with Polymethyl methacrylate. After the formation of Candida albicans biofilm on the resin disks, the antimicrobial activity of the denture cleaning device and the chemical cleanser against C. albicans biofilm was compared. The resin disks were also treated with the cleaning device and the chemical cleanser for 150 days, and the physical properties were analyzed by an atomic force microscope, Vickers hardness tester, and colorimeter.

Results

The denture cleaning device and the chemical cleanser reduced the levels of C. albicans biofilm on the denture resin. Upon immersing of the resin disks for 150 days, the electrolyzed water of the denture cleaning device did not significantly change the surface roughness of the specimens, but significantly reduced its Vickers hardness compared to the initial value. The color changes of the resin disk were 0.477 ± 0.076, 0.612 ± 0.095 and 0.562 ± 0.096 after treating with tap water, the chemical cleanser, and the denture cleaning device, respectively.

Conclusion

The denture cleaning device may be suitable for use by the elderly to clean dentures without side effects caused by the misuse of chemical cleanser.

Electrochemically Reduced Water Delays Mammary Tumors Growth in Mice and Inhibits Breast Cancer Cells Survival In Vitro

Electrochemical reduced water (ERW) has been proposed to have beneficial effects on human health due to its rich content of H₂ and the presence of platinum nanoparticles with antioxidant effects. Many studies have demonstrated that ERW scavenging properties are able to reduce the damage caused by oxidative stress in different experimental models. Although few in vivo studies have been reported, it has been demonstrated that ERW may display anticancer effects by induction of tumor cells apoptosis and reduction of both angiogenesis and inflammation. In this study, we show that ERW treatment of MCF-7, MDA-MB-453, and mouse (TUBO) breast cancer cells inhibited cell survival in a time-dependent fashion. ERW decreased ErbB2/neu expression and impaired pERK1/ERK2 and AKT phosphorylation in breast cancer cells. In addition, ERW treatment induced apoptosis of breast cancer cell lines independently of the status of p53 and ER and PR receptors. Our in vivo results showed that ERW treatment of transgenic BALB-neuT mice delayed the development of mammary tumors compared to the control. In addition, ERW induced a significant prolongation of tumor-free survival and a reduction in tumor multiplicity. Overall, these results suggest a potential beneficial role of ERW in inhibiting cancer cells growth.

Effect of electrolyzed water produced using carbon electrodes on HeLa cell proliferation

We developed electrolyzed water (EW) using carbon electrodes and investigated the ability of the developed EW to inhibit the proliferation of human cervical carcinoma HeLa cells. We observed that EW-containing media inhibited HeLa cell proliferation. Many very small black dots were produced in EW and these were associated with the inhibitory effect on the cell proliferation. Furthermore, the very small black dots that could inhibit cell proliferation were produced only at pH 3 to 3.5 of EW. Additional experiments showed that this inhibition of proliferation is reversible. These results suggest that the effect of EW on HeLa cells is cytostatic and not cytotoxic. Thus, our results indicate that the EW developed in this study may be used to inhibit cell proliretation.

Preventive and therapeutic application of molecular hydrogen in situations with excessive production of free radicals

Excessive production of oxygen free radicals has been regarded as a causative common denominator of many pathological processes in the animal kingdom. Hydroxyl and nitrosyl radicals represent the major cause of the destruction of biomolecules either by a direct reaction or by triggering a chain reaction of free radicals. Scavenging of free radicals may act preventively or therapeutically. A number of substances that preferentially react with free radicals can serve as scavengers, thus increasing the internal capacity/activity of endogenous antioxidants and protecting cells and tissues against oxidative damage. Molecular hydrogen (H(2)) reacts with strong oxidants, such as hydroxyl and nitrosyl radicals, in the cells, that enables utilization of its potential for preventive and therapeutic applications. H(2) rapidly diffuses into tissues and cells without affecting metabolic redox reactions and signaling reactive species. H(2) reduces oxidative stress also by regulating gene expression, and functions as an anti-inflammatory and anti-apoptotic agent. There is a growing body of evidence based on the results of animal experiments and clinical observations that H(2) may represent an effective antioxidant for the prevention of oxidative stress-related diseases. Application of molecular hydrogen in situations with excessive production of free radicals, in particular, hydroxyl and nitrosyl radicals is relatively simple and effective, therefore, it deserves special attention.

New Approach in Translational Medicine: Effects of Electrolyzed Reduced Water (ERW) on NF-κB/iNOS Pathway in U937 Cell Line under Altered Redox State

It is known that increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) can exert harmful effects, altering the cellular redox state. Electrolyzed Reduced Water (ERW) produced near the cathode during water electrolysis exhibits high pH, high concentration of dissolved hydrogen and an extremely negative redox potential. Several findings indicate that ERW had the ability of a scavenger free radical, which results from hydrogen molecules with a high reducing ability and may participate in the redox regulation of cellular function. We investigated the effect of ERW on H₂O₂-induced U937 damage by evaluating the modulation of redox cellular state. Western blotting and spectrophotometrical analysis showed that ERW inhibited oxidative stress by restoring the antioxidant capacity of superoxide dismutase, catalase and glutathione peroxidase. Consequently, ERW restores the ability of the glutathione reductase to supply the cell of an important endogenous antioxidant, such as GSH, reversing the inhibitory effect of H₂O₂ on redox balance of U937 cells. Therefore, this means a reduction of cytotoxicity induced by peroxynitrite via a downregulation of the NF-κB/iNOS pathway and could be used as an antioxidant for preventive and therapeutic application. In conclusion, ERW can protect the cellular redox balance, reducing the risk of several diseases with altered cellular homeostasis such as inflammation.

Molecular hydrogen suppresses activated Wnt/β-catenin signaling

Molecular hydrogen (H₂) is effective for many diseases. However, molecular bases of H₂ have not been fully elucidated. Cumulative evidence indicates that H₂ acts as a gaseous signal modulator. We found that H₂ suppresses activated Wnt/β-catenin signaling by promoting phosphorylation and degradation οf β-catenin. Either complete inhibition of GSK3 or mutations at CK1- and GSK3-phosphorylation sites of β-catenin abolished the suppressive effect of H₂. H₂ did not increase GSK3-mediated phosphorylation of glycogen synthase, indicating that H₂ has no direct effect on GSK3 itself. Knock-down of adenomatous polyposis coli (APC) or Axin1, which form the β-catenin degradation complex, minimized the suppressive effect of H₂ on β-catenin accumulation. Accordingly, the effect of H₂ requires CK1/GSK3-phosphorylation sites of β-catenin, as well as the β-catenin degradation complex comprised of CK1, GSK3, APC, and Axin1. We additionally found that H₂ reduces the activation of Wnt/β-catenin signaling in human osteoarthritis chondrocytes. Oral intake of H₂ water tended to ameliorate cartilage degradation in a surgery-induced rat osteoarthritis model through attenuating β-catenin accumulation. We first demonstrate that H₂ suppresses abnormally activated Wnt/β-catenin signaling, which accounts for the protective roles of H₂ in a fraction of diseases.

Beneficial biological effects and the underlying mechanisms of molecular hydrogen - comprehensive review of 321 original articles

Therapeutic effects of molecular hydrogen for a wide range of disease models and human diseases have been investigated since 2007. A total of 321 original articles have been published from 2007 to June 2015. Most studies have been conducted in Japan, China, and the USA. About three-quarters of the articles show the effects in mice and rats. The number of clinical trials is increasing every year. In most diseases, the effect of hydrogen has been reported with hydrogen water or hydrogen gas, which was followed by confirmation of the effect with hydrogen-rich saline. Hydrogen water is mostly given ad libitum. Hydrogen gas of less than 4 % is given by inhalation. The effects have been reported in essentially all organs covering 31 disease categories that can be subdivided into 166 disease models, human diseases, treatment-associated pathologies, and pathophysiological conditions of plants with a predominance of oxidative stress-mediated diseases and inflammatory diseases. Specific extinctions of hydroxyl radical and peroxynitrite were initially presented, but the radical-scavenging effect of hydrogen cannot be held solely accountable for its drastic effects. We and others have shown that the effects can be mediated by modulating activities and expressions of various molecules such as Lyn, ERK, p38, JNK, ASK1, Akt, GTP-Rac1, iNOS, Nox1, NF-κB p65, IκBα, STAT3, NFATc1, c-Fos, and ghrelin. Master regulator(s) that drive these modifications, however, remain to be elucidated and are currently being extensively investigated.

Hydrogen resuscitation, a new cytoprotective approach

1. Hydrogen is a colourless, odourless, tasteless and flammable gas. Hydrogen is considered a physiologically inert gas and is often used in deep sea diving medicine. In mammals, endogenous hydrogen is produced as a result of the fermentation of non-digestible carbohydrates by intestinal bacteria and it is absorbed into the systemic circulation. 2. Recent evidence indicates that hydrogen is a potent anti-oxidative, anti-apoptotic and anti-inflammatory agent and so may have potential medical application. The present review evaluates the concept of 'hydrogen resuscitation', based on knowledge that hydrogen treatment effectively protects cells, tissues and organs against oxidative injury and helps them recover from dysfunction. 3. Hydrogen therapy can be delivered by inhalation, the administration of hydrogen-enriched fluid or by approaches that affect endogenous hydrogen production. 4. Studies have shown that hydrogen resuscitation has cytoprotective effects in different cell types and disease models, including ischaemia-reperfusion injury, inflammation, toxicity, trauma and metabolic disease. The underlying mechanism may be the selective elimination of hydroxyl radicals, although other mechanisms may also be involved (e.g. hydrogen functioning as a gaseous signalling molecule). 5. Hydrogen resuscitation may have several potential advantages over current pharmacological therapies for oxidative injuries. However, more work is needed to identify the precise mechanism underlying the actions of hydrogen and to validate its therapeutic potential in the clinical setting.

Electrochemically reduced water protects neural cells from oxidative damage

Aging-related neurodegenerative disorders are closely associated with mitochondrial dysfunction and oxidative stresses and their incidence tends to increase with aging. Brain is the most vulnerable to reactive species generated by a higher rate of oxygen consumption and glucose utilization compared to other organs. Electrochemically reduced water (ERW) was demonstrated to scavenge reactive oxygen species (ROS) in several cell types. In the present study, the protective effect of ERW against hydrogen peroxide (H₂O₂) and nitric oxide (NO) was investigated in several rodent neuronal cell lines and primary cells. ERW was found to significantly suppress H₂O₂ (50–200 μM) induced PC12 and SFME cell deaths. ERW scavenged intracellular ROS and exhibited a protective effect against neuronal network damage caused by 200 μM H₂O₂ in N1E-115 cells. ERW significantly suppressed NO-induced cytotoxicity in PC12 cells despite the fact that it did not have the ability to scavenge intracellular NO. ERW significantly suppressed both glutamate induced Ca²⁺ influx and the resulting cytotoxicity in primary cells. These results collectively demonstrated for the first time that ERW protects several types of neuronal cells by scavenging ROS because of the presence of hydrogen and platinum nanoparticles dissolved in ERW.

Removal efficiency of radioactive cesium and iodine ions by a flow-type apparatus designed for electrochemically reduced water production

The Fukushima Daiichi Nuclear Power Plant accident on March 11, 2011 attracted people’s attention, with anxiety over possible radiation hazards. Immediate and long-term concerns are around protection from external and internal exposure by the liberated radionuclides. In particular, residents living in the affected regions are most concerned about ingesting contaminated foodstuffs, including drinking water. Efficient removal of radionuclides from rainwater and drinking water has been reported using several pot-type filtration devices. A currently used flow-type test apparatus is expected to simultaneously provide radionuclide elimination prior to ingestion and protection from internal exposure by accidental ingestion of radionuclides through the use of a micro-carbon carboxymethyl cartridge unit and an electrochemically reduced water production unit, respectively. However, the removability of radionuclides from contaminated tap water has not been tested to date. Thus, the current research was undertaken to assess the capability of the apparatus to remove radionuclides from artificially contaminated tap water. The results presented here demonstrate that the apparatus can reduce radioactivity levels to below the detection limit in applied tap water containing either 300 Bq/kg of ¹³⁷Cs or 150 Bq/kg of ¹²⁵I. The apparatus had a removal efficiency of over 90% for all concentration ranges of radio–cesium and –iodine tested. The results showing efficient radionuclide removability, together with previous studies on molecular hydrogen and platinum nanoparticles as reactive oxygen species scavengers, strongly suggest that the test apparatus has the potential to offer maximum safety against radionuclide-contaminated foodstuffs, including drinking water.

Dose-dependent inhibition of gastric injury by hydrogen in alkaline electrolyzed drinking water

Background

Hydrogen has been reported to relieve damage in many disease models, and is a potential additive in drinking water to provide protective effects for patients as several clinical studies revealed. However, the absence of a dose–response relationship in the application of hydrogen is puzzling. We attempted to identify the dose–response relationship of hydrogen in alkaline electrolyzed drinking water through the aspirin induced gastric injury model.

Methods

In this study, hydrogen-rich alkaline water was obtained by adding H₂ to electrolyzed water at one atmosphere pressure. After 2 weeks of drinking, we detected the gastric mucosal damage together with MPO, MDA and 8-OHdG in rat aspirin induced gastric injury model.

Results

Hydrogen-dose dependent inhibition was observed in stomach mucosal. Under pH 8.5, 0.07, 0.22 and 0.84 ppm hydrogen exhibited a high correlation with inhibitory effects showed by erosion area, MPO activity and MDA content in the stomach. Gastric histology also demonstrated the inhibition of damage by hydrogen-rich alkaline water. However, 8-OHdG level in serum did not have significant hydrogen-dose dependent effect. pH 9.5 showed higher but not significant inhibitory response compared with pH 8.5.

Conclusions

Hydrogen is effective in relieving the gastric injury induced by aspirin-HCl, and the inhibitory effect is dose-dependent. The reason behind this may be that hydrogen-rich water directly interacted with the target tissue, while the hydrogen concentration in blood was buffered by liver glycogen, evoking a suppressed dose–response effect. Drinking hydrogen-rich water may protect healthy individuals from gastric damage caused by oxidative stress.

Consumption of hydrogen-rich water protects against ferric nitrilotriacetate-induced nephrotoxicity and early tumor promotional events in rats

The aim of this work was to test whether consumption with hydrogen-rich water (HW) alleviated renal injury and inhibited early tumor promotional events in Ferric nitrilotriacetate (Fe-NTA)-treated rats. Rats were injected with Fe-NTA solution (7.5mg Fe/kg body weight) intraperitoneally to induce renal injury and simultaneously treated with HW (1.3 ± 0.2mg/l). We found that consumption with HW ameliorated Fe-NTA-induced renal injuries including suppressing elevation of serum creatinine and blood urea nitrogen and inhibited early tumor promotional events including decreasing ornithine decarboxylase activity and incorporation of [3H]thymidine into renal DNA. Consumption with HW suppressed Fe-NTA-induced oxidative stress through decreasing formation of lipid peroxidation and peroxynitrite and activities of NADPH oxidase and xanthine oxidase, increasing activity of catalase, and restoring mitochondrial function in kidneys. Consumption with HW suppressed Fe-NTA-induced inflammation marked by reduced NF-κB, IL-6, and MCP-1 expression and macrophage accumulating in kidneys. In addition, consumption with HW suppressed VEGF expression, STAT3 phosphorylation and PCNA expression in kidneys of Fe-NTA-treated rats. Consumption with HW decreased the incidence of renal cell carcinoma and suppressed tumor growth in Fe-NTA-treated in rats. In conclusion, drinking with HW attenuated Fe-NTA-induced renal injury and inhibited early tumor promotional events in rats.

Protective effects of hydrogen-rich saline on ulcerative colitis rat model

BACKGROUND

Ulcerative colitis (UC) is associated with enhanced production of reactive oxygen species and altered angiogenesis. Molecular hydrogen has been documented as a novel antioxidant to treat various reactive oxygen species-related diseases. The present study aimed to investigate the effects of hydrogen on UC using a rat model.

MATERIALS AND METHODS

UC in rats was induced with intracolonically administrated acetic acid. Hydrogen was supplied through intraperitoneal injection of 10 or 20 mL/kg hydrogen-rich saline. The hydrogen treatment was performed once every 2 d and lasted 2 wk. The stool consistency and weight loss were used to evaluate UC development. Colonic mucosal damage at the end of the experiment was scored using the macroscopic and microscopic observations. Vascular endothelial growth factor expression in the colonic mucosa was determined using immunohistochemistry.

RESULTS

The administration of acetic acid induced acute rat UC, as indicated by diarrhea, weight loss, and colonic mucosal damage. Treatment with hydrogen-rich saline reduced the weight loss and diarrhea and alleviated the colonic mucosal damage in the UC rats. In addition, the expression of vascular endothelial growth factor in the UC rats increased and could be inhibited by hydrogen treatment.

CONCLUSIONS

Antioxidative hydrogen-rich saline effectively protected the rats from UC, which might be, at least in part, because of inhibition of vascular endothelial growth factor.

Suppressive effects of electrochemically reduced water on matrix metalloproteinase-2 activities and in vitro invasion of human fibrosarcoma HT1080 cells

It has been demonstrated that hydrogen peroxide (H(2)O(2)) is directly associated with elevated matrix metalloproteinase-2 (MMP-2) expression in several cell lines. Electrochemically reduced water (ERW), produced near the cathode during electrolysis, and scavenges intracellular H(2)O(2) in human fibrosarcoma HT1080 cells. RT-PCR and zymography analyses revealed that when HT1080 cells were treated with ERW, the gene expression of MMP-2 and membrane type 1 MMP and activation of MMP-2 was repressed, resulting in decreased invasion of the cells into matrigel. ERW also inhibited H(2)O(2)-induced MMP-2 upregulation. To investigate signal transduction involved in MMP-2 downregulation, mitogen-activated protein kinase (MAPK)-specific inhibitors, SB203580 (p38 MAPK inhibitor), PD98059 (MAPK/extracellular regulated kinase kinase 1 inhibitor) and c-Jun NH(2)-terminal kinase inhibitor II, were used to block the MAPK signal cascade. MMP-2 gene expression was only inhibited by SB203580 treatment, suggesting a pivotal role of p38 MAPK in regulation of MMP-2 gene expression. Western blot analysis showed that ERW downregulated the phosphorylation of p38 both in H(2)O(2)-treated and untreated HT1080 cells. These results indicate that the inhibitory effect of ERW on tumor invasion is due to, at least in part, its antioxidative effect.

Molecular hydrogen as an emerging therapeutic medical gas for neurodegenerative and other diseases

Effects of molecular hydrogen on various diseases have been documented for 63 disease models and human diseases in the past four and a half years. Most studies have been performed on rodents including two models of Parkinson's disease and three models of Alzheimer's disease. Prominent effects are observed especially in oxidative stress-mediated diseases including neonatal cerebral hypoxia; Parkinson's disease; ischemia/reperfusion of spinal cord, heart, lung, liver, kidney, and intestine; transplantation of lung, heart, kidney, and intestine. Six human diseases have been studied to date: diabetes mellitus type 2, metabolic syndrome, hemodialysis, inflammatory and mitochondrial myopathies, brain stem infarction, and radiation-induced adverse effects. Two enigmas, however, remain to be solved. First, no dose-response effect is observed. Rodents and humans are able to take a small amount of hydrogen by drinking hydrogen-rich water, but marked effects are observed. Second, intestinal bacteria in humans and rodents produce a large amount of hydrogen, but an addition of a small amount of hydrogen exhibits marked effects. Further studies are required to elucidate molecular bases of prominent hydrogen effects and to determine the optimal frequency, amount, and method of hydrogen administration for each human disease.

Hydrogen-rich electrolyzed warm water represses wrinkle formation against UVA ray together with type-I collagen production and oxidative-stress diminishment in fibroblasts and cell-injury prevention in keratinocytes

Hydrogen-rich electrolyzed warm water (HW) was prepared at 41°C and exhibited dissolved hydrogen (DH) of 1.13 ppm and an oxidation-reduction potential (ORP) of -741 mV in contrast to below 0.01 ppm and+184 mV for regular warm water (RW). Fibroblasts OUMS-36 and keratinocytes HaCaT were used to examine effects of HW against UVA-ray irradiation. Type-I collagen was synthesized 1.85- to 2.03-fold more abundantly by HW application for 3-5 days than RW in OUMS-36 fibroblasts, and localized preferentially around the nuclei as shown by immunostain. HW application significantly prevented cell death and DNA damages such as nuclear condensation and fragmentation in UVA-irradiated HaCaT keratinocytes as estimated by WST-1 and Hoechst 33342 assays. HW significantly suppressed UVA-induced generation of intracellular superoxide anion radicals in both the cell lines according to NBT assay. Wrinkle repression was clinically assessed using a HW-bathing. Six Japanese subjects were enrolled in a trial of HW-bathing (DH, 0.2-0.4 ppm) every day for 3 months. HW-bathing significantly improved wrinkle in four subjects on the back of neck on 90th day as compared to 0 day. Thus, HW may serve as daily skin care to repress UVA-induced skin damages by ROS-scavenging and promotion of type-I collagen synthesis in dermis.

Mechanism of the lifespan extension of Caenorhabditis elegans by electrolyzed reduced water--participation of Pt nanoparticles

Electrolyzed reduced water (ERW) contains a large amount of molecular hydrogen and a small amount of Pt nanoparticles (Pt NPs). We have found that ERW significantly extended the lifespan of Caenorhabditis elegans in a novel culture medium designated Water Medium. In this study, we found that synthetic Pt NPs at ppb levels significantly extended the nematode lifespan and scavenged reactive oxygen species (ROS) in the nematode induced by paraquat treatment. In contrast, a high concentration of dissolved molecular hydrogen had no significant effect on the lifespan of the nematode. These findings suggest that the Pt NPs in ERW, rather than the molecular hydrogen, extend the longevity of the nematode, at least partly by scavenging ROS.

The 2011 Medical Molecular Hydrogen Symposium: An inaugural symposium of the journal Medical Gas Research

This report summarizes a brief description/history of the Hydrogen Research Meetings as well as key presentations/oral abstracts delivered in the most recent symposium. Additionally, we introduced 38 diseases and physiological states for which hydrogen exhibits beneficial effects.

The melamine excretion effect of the electrolyzed reduced water in melamine-fed mice

Our hypothesis is that the intake of functional water, electrolyzed reduced water (ERW) can excrete melamine in body was evoked by melamine-tainted feed (MTF). To address this issue, we investigated the effect of ERW in MTF-mice model by way of body weight gain, incidence of urinary crystals and bladder stone, biochemical and haematological examination, histopathologic finding of kidney and urinary bladder, and the evaluation of bladder stone. We found that the rate of body weight gain was significantly more increased in MTF+ERW group than MTF+PW group. Accordingly, the number of immunocytes such as leukocyte, neutrophil and monocyte as well as the mean weight of spleen was significantly increased in MTF+ERW group. The incidence of urinary crystals was significantly higher in MTF+ERW group, whereas the incidence of urinary bladder stones was lower in MTF+ERW group (52.4%) than in MTF+PW group (38.1%). Also, urinary crystals were more precipitated in MTF+ERW group than MTF+PW group, and urinary bladder stone consists of 100% melamine. Collectively, our data clearly show that ERW intake is helpful to excrete of melamine in MTF mice model and this is the first report on the melamine excretion and clinically implying the safer fluid remedy for melamine-intoxicated hosts.

Suppressive effects of electrolyzed reduced water on alloxan-induced apoptosis and type 1 diabetes mellitus

Electrolyzed reduced water, which is capable of scavenging reactive oxygen species, is attracting recent attention because it has shown improved efficacy against several types of diseases including diabetes mellitus. Alloxan produces reactive oxygen species and causes type 1 diabetes mellitus in experimental animals by irreversible oxidative damage to insulin-producing β-cells. Here, we showed that electrolyzed reduced water prevented alloxan-induced DNA fragmentation and the production of cells in sub-G1 phase in HIT-T15 pancreatic β-cells. Blood glucose levels in alloxan-induced type 1 diabetes model mice were also significantly suppressed by feeding the mice with electrolyzed reduced water. These results suggest that electrolyzed reduced water can prevent apoptosis of pancreatic β-cells and the development of symptoms in type 1 diabetes model mice by alleviating the alloxan-derived generation of reactive oxygen species.

Targeting anticancer drugs to tumor vasculature using cationic liposomes

Liposomal drug delivery systems improve the therapeutic index of chemotherapeutic agents, and the use of cationic liposomes to deliver anticancer drugs to solid tumors has recently been recognized as a promising therapeutic strategy to improve the effectiveness of conventional chemotherapeutics. This review summarizes the selective targeting of cationic liposomes to tumor vasculature, the merits of incorporating the polymer polyethylene-glycol (PEG), and the impact of the molar percent of the cationic lipid included in cationic liposomes on liposomal targeting efficacy. In addition, the discussion herein includes the therapeutic benefit of a dual targeting approach, using PEG-coated cationic liposomes in vascular targeting (of tumor endothelial cells), and tumor targeting (of tumor cells) of anticancer drugs. Cationic liposomes have shown considerable promise in preclinical xenograft models and are poised for clinical development.

Recent advances in tumor vasculature targeting using liposomal drug delivery systems

Tumor vessels possess unique physiological features that might be exploited for improved drug delivery. The targeting of liposomal anticancer drugs to tumor vasculature is increasingly recognized as an effective strategy to obtain superior therapeutic efficacy with limited host toxicity compared with conventional treatments. This review introduces recent advances in the field of liposomal targeting of tumor vasculature, along with new approaches that can be used in the design and optimization of liposomal delivery systems. In addition, cationic liposome is focused on as a promising carrier for achieving efficient vascular targeting. The clinical implications are discussed of several approaches using a single liposomal anticancer drug formulation: dual targeting, vascular targeting (targeting tumor endothelial cells) and tumor targeting (targeting tumor cells).

Hepatoprotective effect of electrolyzed reduced water against carbon tetrachloride-induced liver damage in mice

The study investigated the protective effect of electrolyzed reduced water (ERW) against carbon tetrachloride (CCl(4))-induced liver damage. Male ICR mice were randomly divided into control, CCl(4), CCl(4)+silymarin, and CCl(4)+ERW groups. CCl(4)-induced liver lesions include leukocytes infiltration, hepatocyte necrosis, ballooning degeneration, mitosis, calcification, fibrosis and an increase of serum alanine aminotransferase (ALT), and aminotransferase (AST) activity. In addition, CCl(4) also significantly decreased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). By contrast, ERW or silymarin supplement significantly ameliorated the CCl(4)-induced liver lesions, lowered the serum levels of hepatic enzyme markers (ALT and AST) and increased the activities of SOD, catalase, and GSH-Px in liver. Therefore, the results of this study show that ERW can be proposed to protect the liver against CCl(4)-induced oxidative damage in mice, and the hepatoprotective effect might be correlated with its antioxidant and free radical scavenging effect.

Oxaliplatin targeting to angiogenic vessels by PEGylated cationic liposomes suppresses the angiogenesis in a dorsal air sac mouse model

Oxaliplatin (trans-l-diaminocyclohexane oxalatoplatinum, l-OHP) is a third-generation platinum analogue with proven anti-tumor activity against many tumor cell lines, however it does not show sufficient anti-tumor activity in vivo when used alone. In order to overcome this problem and to achieve an anti-angiogenic therapy with l-OHP, the drug was encapsulated into PEG-coated cationic liposomes, which were designed to target the newly formed vessels, and its anti-angiogenic activity was evaluated in an in vivo mouse dorsal air sac (DAS) assay. For the DAS assay, chambers filled with tumor cells were implanted underneath the dorsal skin. l-OHP encapsulated in PEG-coated cationic liposomes (5 mg/kg mice) was intravenously injected once on day 1, 2, 3 or 4 after chamber implantation. On the fifth day after chamber implantation, animals were sacrificed and tumor-angiogenesis was evaluated. Liposome-encapsulated l-OHP completely suppressed angiogenesis in the skin when it was administered day 3 after chamber implantation. Under similar experimental conditions, neither l-OHP encapsulated in PEG-coated neutral liposomes, nor free l-OHP, nor "empty" (no drug containing) PEG-coated cationic liposomes showed such strong suppressive effect. The present study suggests that the liposomal formulation of l-OHP, which targeted to angiogenic vessels, has a remarkable in vivo anti-angiogenic activity and the formulation may become a promising novel approach to achieve anti-angiogenic therapy.