Alcoholic Fatty Liver Disease (AFLD) is characterized by the accumulation of lipids in liver cells owing to the metabolism of ethanol. This process leads to a decrease in the NAD+/NADH ratio and the generation of reactive oxygen species. A systematic review and meta-analysis were conducted to investigate the role of oxidative stress in AFLD. A total of 201 eligible manuscripts were included, which revealed that animals with AFLD exhibited elevated expression of CYP2E1, decreased enzymatic activity of antioxidant enzymes, and reduced levels of the transcription factor Nrf2, which plays a pivotal role in the synthesis of antioxidant enzymes. Furthermore, animals with AFLD exhibited increased levels of lipid peroxidation markers and carbonylated proteins, collectively contributing to a weakened antioxidant defense and increased oxidative damage. The liver damage in AFLD was supported by significantly higher activity of alanine and aspartate aminotransferase enzymes. Moreover, animals with AFLD had increased levels of triacylglycerol in the serum and liver, likely due to reduced fatty acid metabolism caused by decreased PPAR-α expression, which is responsible for fatty acid oxidation, and increased expression of SREBP-1c, which is involved in fatty acid synthesis. With regard to inflammation, animals with AFLD exhibited elevated levels of pro-inflammatory cytokines, including TNF-a, IL-1β, and IL-6. The heightened oxidative stress, along with inflammation, led to an upregulation of cell death markers, such as caspase-3, and an increased Bax/Bcl-2 ratio. Overall, the findings of the review and meta-analysis indicate that ethanol metabolism reduces important markers of antioxidant defense while increasing inflammatory and apoptotic markers, thereby contributing to the development of AFLD.

Cadmium is a major environmental pollutant and a highly toxic metal. It was aimed to determine the effects of pomegranate peel extract (PPE), N-acetylcysteine (NAC) alone and along with Ornipural on cadmium-induced toxicity. Forty-six Wistar Albino male rats were divided into 6 groups and the groups were formed into healthy control, Cadmium group (5 mg/kg/day, oral), Cadmium + Pomegranate peel extract (500 mg/kg, oral), Cadmium + N-acetylcysteine (100 mg/kg, oral), Cadmium + Pomegranate peel extract (500 mg/kg, oral) + Ornipural (1 mL/kg, subcutaneous) and Cadmium + N-acetylcysteine (100 mg/kg, oral) + Ornipural (1 mL/kg, subcutaneous). Cadmium accumulated heavily in both liver and kidney tissue. The administration of N-acetylcysteine and pomegranate peel extract alone reduced cadmium levels in both tissues. N-acetylcysteine treatment prevented the increase in ALT and MDA levels by cadmium damage. N-acetylcysteine + Ornipural treatment inhibited the increase in liver 8-OHdG level in the liver. N-acetylcysteine and N-acetylcysteine + Ornipural treatments prevented the reduced serum MMP2 level. N-acetylcysteine and Pomegranate peel extract + Ornipural treatments significantly reduced the increased liver iNOS level in the liver. In conclusion, NAC therapy may be a successful treatment option for cadmium toxicity. However, further research is needed on the effects of PPE and Ornipural combinations for the treatment of cadmium toxicity. In future studies, various doses of these treatment options (with chelators) should be investigated for cadmium toxicity.

Liver fibrosis has a high incidence worldwide and is the common pathological basis of many chronic liver diseases. Liver fibrosis is caused by the excessive deposition of extracellular matrix and concomitant collagen accumulation in livers and can lead to the development of liver cirrhosis and even liver cancer. A large number of studies have provided evidence that liver fibrosis can be blocked or even reversed by appropriate medical interventions. However, the antifibrosis drugs with ideal clinical efficacy are still insufficient. The edible plant-derived natural compounds have been reported to exert effective antifibrotic effects with few side-effects, representing a kind of promising source for the treatment of liver fibrosis. In this article, we reviewed the current progress of the natural compounds derived from dietary plants in the treatment of liver fibrosis, including phenolic compounds (capsaicin, chlorogenic acid, curcumin, ellagic acid, epigallocatechin-3-gallate, resveratrol, sinapic acid, syringic acid, vanillic acid and vitamin E), flavonoid compounds (genistein, hesperidin, hesperetin, naringenin, naringin and quercetin), sulfur-containing compounds (S-allylcysteine, ergothioneine, lipoic acid and sulforaphane) and other compounds (betaine, caffeine, cucurbitacin B, lycopene, α-mangostin, γ-mangostin, ursolic acid, vitamin C and yangonin). The pharmacological effects and related mechanisms of these compounds in in-vivo and in-vitro models of liver fibrosis are focused.

The harmful use of alcohol is a worldwide problem involving all ages. This study aims to investigate chronic alcohol exposure related hepatotoxicity on the rat liver and possible hepatoprotective effects of boric acid. Rats were separated into 4 different groups: control, ethanol, ethanol+boric acid, and boric acid. We measured (i) malondialdehyde (MDA), total sialic acid (TSA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) levels, which are known to be the markers of alcohol damage; and also (ii) caspase-3, tumor necrosis factor-alpha (TNF-α), and the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) as the markers of apoptosis. In the ethanol group, MDA, TSA, and TNF-α levels increased whereas SOD and CAT levels decreased compared with the control group. Ethanol+boric acid group MDA, TSA, caspase-3, and TNF-α levels decreased whereas SOD and CAT levels increased compared with the ethanol group. Using histopathological evaluation of light microscope images, immunohistochemical caspase-3 and TNF-α activity in the ethanol+boric acid group were shown to be decreased compared with that in the ethanol group. Our results revealed that ethanol is capable of triggering oxidative stress and apoptosis in the rat liver. We propose that boric acid is an effective compound in protecting the rat liver against ethanol.

Aging is accompanied by the accumulation of cellular damage over time in response to stress, lifestyle and environmental factors ultimately leading to age-related diseases and death. Additionally, the number of senescent cells increases with age. Senescence is most likely not a static endpoint, it represents a series of hallmarks including morphological changes, alterations in protein turnover and accumulation of protein aggregates. The importance of protein oxidation and aggregate accumulation in the progression of aging is not yet fully understood and research to what extent the accumulation of oxidized proteins has an effect on senescence and the aging process is still ongoing. To study the mechanisms of aging, the impact of senescence and the role of protein aggregates on the aging process, cell culture models are useful tools. Most notably stress induced premature senescence (SIPS) models have contributed to the identification of mechanisms involved in the aging process and helped unravel the age-related changes in proteolysis and the importance of protein aggregation. Here we review characteristics of replicative and premature senescence, how to induce most frequently used senescence models and gained knowledge on age-related changes in the major proteolytic systems.

The aim of this study was to determine possible protective influences of selenium (Se), N-acetylcysteine (NAC), and vitamin E (Vit E) against acute ethanol (EtOH) intoxication. Thirty-six rats were divided into six groups: I (control), II (EtOH), III (EtOH + Se), IV (EtOH + Vit E), V (EtOH + NAC), and VI (EtOH + mix). Except group I, EtOH was given the other pretreated (groups III, IV, V, and VI) and untreated groups (group II). Compared with the EtOH group, serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase, and creatine kinase-MB levels were significantly decreased in all pretreated groups, whereas slightly diminished amylase and lipase were observed. Compared with the control group, a remarkably lower total antioxidant status (TAS), but higher total oxidant status (TOS), and oxidative stress index (OSI) were seen in brain, liver, and kidney tissues. The values of these parameters were less affected from EtOH-exposed brain tissue of EtOH + NAC and liver of EtOH + mix groups. Both significant decrease of catalase activity and marked increases of adenosine deaminase and myeloperoxidase were determined only in liver tissue of the EtOH group. Activities of these enzymes were restored in almost all pretreated groups. Moreover, an increase of xanthine oxidase activity was prevented in brain tissue of pretreated groups. In histopathological examination of the liver, hydropic degeneration, sinusoidal dilatation, mononuclear cell infiltration, and marked congestion, which were seen in the EtOH group, were prevented in all pretreated groups. Relative protection against acute EtOH toxicity, in both single and combined pretreatments of Se, NAC, and Vit E supplementation, was probably through antioxidant and free radical-neutralizing effects of foregoing materials.

Betaine (BET) is a native compound widely studied as an antioxidant in agriculture and human health. However, the antioxidant mechanism of BET remains unclear. In this research, radical scavenging assays showed that BET had little free radical scavenging activity. However, the antioxidant activity of BET was confirmed by cellular antioxidant activity (CAA) and erythrocyte hemolysis assays. The results of quantitative PCR (qPCR) and enzyme activity determination kits showed that the antioxidant activity of BET was not due to the gene expression and activity of antioxidases. High-pressure liquid chromatography (HPLC) assessment of the effect of BET on sulfur-containing amino acid metabolism showed that BET increased the levels of nonenzymatic antioxidants,S-adenosylmethionine (SAM) and methionine (p < 0.05), via the regulation of the methionine-omocysteine cycle. Additionally, the three methyl groups of BET were found to play a key role in its antioxidant activity. The possible reason was that because of the hydrophobicity of the three methyl groups and hydrophilicity of the carboxyl of BET, a tight protective membrane was formed around cells to prevent oxidative stress inducer from inducing ROS generation and cell damage. In conclusion, the antioxidant mechanism of BET was found to enhance nonenzymatic antioxidant defenses via the methionine-homocysteine cycle and form a protective membrane around cells.

Excess use of alcohol is known to be associated with liver diseases such as fatty liver, alcoholic hepatitis, and cirrhosis. Various practices may be applied to prevent or treat the damage caused by chronic alcoholism. Coprinus comatus (O.F. Müll.) Pers. (Agaricaceae) is a macrofungus that has been reported to aid the recovery of murine livers damaged by benzopyrene.

In this study, the possible therapeutic effects of three different doses (50, 100, and 150 mg/kg) of C. comatus polysaccharide (PS) extract were studied in rats subjected to an alcoholic diet. The histological and biochemical results were compared between the control and experimental groups.

Modified Lieber-Decarli's calorie-adjusted liquid alcohol diet was given orally for 60 d. In addition to histopathology, alanine transaminase (ALT), aspartate transaminase (AST), mitochondrial membrane integrity, total cytochrome-c oxidase activity (TotalStCox), total mitochondrial cytochrome-c oxidase activity (TotalMtStCox), and caspase-3 values were used as liver parameters, and liver sections from all experimental groups were examined by electron microscopy.

Using histopathological assessment, it was observed that there was a decline in liver hepatocyte vacuolization in the treatment group fed 50 mg PS/kg. The TotalStCox and TotalMtStCox values of this group differed from the EtOH control group (p < 0.05).

Daily administration of 50 mg/kg of C. comatus PS extract considerably reduced the negative effects of alcohol on liver structure and function.

Rotenone is an inhibitor of mitochondrial complex I-induced neurotoxicity in PC12 cells and has been widely studied to elucidate the pathogenesis of Parkinson's disease. We investigated the neuroprotective effects of betaine on rotenone-induced neurotoxicity in PC12 cells. Betaine inhibited rotenone-induced apoptosis in a dose-dependent manner, with cell viability increasing from 50 % with rotenone treatment alone to 71 % with rotenone plus 100-μM betaine treatment. Flow cytometric analysis demonstrated cell death in the rotenone-treated cells to be over 50 %; the number of live cells increased with betaine pretreatment. Betaine pretreatment of PC12 cells attenuated rotenone-mediated mitochondrial dysfunction, including nuclear fragmentation, ATP depletion, mitochondrial membrane depolarization, caspase-3/7 activation, and reactive oxygen species production. Western blots demonstrated activation of caspase-3 and caspase-9, and their increased expression levels in rotenone-treated cells; betaine decreased caspase-3 and caspase-9 expression levels and suppressed their activation. Together, these results suggest that betaine may serve as a neuroprotective agent in the treatment of neurodegenerative diseases.

Introduction. Mitochondrial damage and disruption in oxidative phosphorylation contributes to the pathogenesis of alcoholic liver injury. Herein, we tested the hypothesis that the hepatoprotective actions of betaine against alcoholic liver injury occur at the level of the mitochondrial proteome. Methods. Male Wister rats were pair-fed control or ethanol-containing liquid diets supplemented with or without betaine (10 mg/mL) for 4-5 wks. Liver was examined for triglyceride accumulation, levels of methionine cycle metabolites, and alterations in mitochondrial proteins. Results. Chronic ethanol ingestion resulted in triglyceride accumulation which was attenuated in the ethanol plus betaine group. Blue native gel electrophoresis (BN-PAGE) revealed significant decreases in the content of the intact oxidative phosphorylation complexes in mitochondria from ethanol-fed animals. The alcohol-dependent loss in many of the low molecular weight oxidative phosphorylation proteins was prevented by betaine supplementation. This protection by betaine was associated with normalization of SAM : S-adenosylhomocysteine (SAH) ratios and the attenuation of the ethanol-induced increase in inducible nitric oxide synthase and nitric oxide generation in the liver. Discussion/Conclusion. In summary, betaine attenuates alcoholic steatosis and alterations to the oxidative phosphorylation system. Therefore, preservation of mitochondrial function may be another key molecular mechanism responsible for betaine hepatoprotection.

In recent years, the medicinal mushroom Antrodia cinnamomea, known as "niu-chang chih" has received much attention with regard to its possible health benefits; especially its hepatoprotective effects against various drugs, toxins, and alcohol induced liver diseases. However, the molecular mechanism underlying this protective effect of Antrodia cinnamomea and its active compound antroquinonol was poorly understood. In the present study we evaluated to understand the hepatoprotective efficacy of antroquinonol and ethanolic extracts of mycelia of Antrodia cinnamomea (EMAC) in vitro and in vivo.

The protective mechanism of antroquinonol and EMAC against ethanol-induced oxidative stress was investigated in cultured human hepatoma HepG2 cells and ICR mice model, respectively. HepG2 cells were pretreated with antroquinonol (1-20μM) and oxidative stress was induced by ethanol (100mM). Meanwhile, male ICR mice were pretreated with EMAC for 10 days and hepatotoxicity was generated by the addition of ethanol (5g/kg). Hepatic enzymes, cytokines and chemokines were determined using commercially available assay kits. Western blotting and real-time PCR were subjected to analyze HO-1 and Nr-2 expression. EMSA was performed to monitor Nrf-2 ARE binding activity. Possible changes in hepatic lesion were observed using histopathological analysis.

Antroquinonol pretreatment significantly inhibited ethanol-induced AST, ALT, ROS, NO, MDA production and GSH depletion in HepG2 cells. Western blot and RT-PCR analysis showed that antroquinonol enhanced Nrf-2 activation and its downstream antioxidant gene HO-1 via MAPK pathway. This mechanism was then confirmed in vivo in an acute ethanol intoxicated mouse model: serum ALT and AST production, hepatocellular lipid peroxidation and GSH depletion was prevented by EMAC in a dose-dependent manner. EMAC significantly enhanced HO-1 and Nrf-2 activation via MAPKs consistent with in vitro studies. Ethanol-induced hepatic swelling and hydropic degeneration of hepatocytes was significantly inhibited by EMAC in a dose-dependent manner.

These results provide a scientific basis for the hepatoprotective effects of Antrodia cinnamomea. Data also imply that antroquinonol, a potent bioactive compound may be responsible for the hepatoprotective activity of Antrodia cinnamomea. Moreover, the present study highly supported our traditional knowledge that Antrodia cinnamomea as a potential candidate for the treatment of alcoholic liver diseases.

This study compares the curative effect of three antioxidants-ascorbic acid, quercetin, and thiamine-on ethanol-induced toxicity in rats. Administration of ethanol at a dose of 4 g/kg of body weight/day for 90 days initiated chronic alcohol-induced oxidative stress as shown by increased malondialdehyde level and DNA fragmentation in liver and brain. Ethanol administration also led to a decrease in DNA content. Activities of toxicity marker enzymes-alanine aminotransferase, aspartate aminotransferase, and γ-glutamyltranspeptidase-in liver and serum increased progressively upon ethanol administration. After ethanol administration for 90 days, the efficacy of antioxidant treatment of the alcohol-induced toxicity was studied by supplementing ascorbic acid (200 mg/100 g of body weight/day), quercetin (50 mg/kg of body weight/day), and thiamine (25 mg/kg of body weight/day) for 30 days. These groups were compared with the abstention group (not treated with ethanol). All the alterations induced by alcohol were reduced significantly by the supplementation of antioxidants and also with abstention. The regression by antioxidants was greater that of abstention. Antioxidants significantly reduced the oxidative stress induced by ethanol intoxication, increased membrane integrity, and also increased organ regeneration. Ascorbic acid was shown to be more effective than quercetin and thiamine in treating both hepatotoxicity and neurotoxicity induced by alcohol administration. This may be due to the higher antioxidant potential of ascorbic acid in physiological conditions.

In this study, the effect of combination of vitamin C (ascorbic acid), vitamin E (alpha -tocopherol), and selenium (sodium selenate) on ethanol-induced liver and intestine injury in rats was investigated. The ethanol-induced injury was produced by the administration of 1 ml of absolute ethanol to each rats. Animals received vitamin C (250 mg/kg), vitamin E (250 mg/kg), and sodium selenate (Se) (0.5 mg/kg) for 3 days; 1 h after the final antioxidant administration, they were sacrificed. Lipid peroxidation and glutathione levels, catalase (CAT), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and glutathione peroxidase (GP(x)) activities were determined in liver and intestine tissues. Myeloperoxidase (MPO), aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT) were determined in liver tissue. Also, CAT activity, urea, creatinine, uric acid, and total lipid levels were determined in serum samples. In the ethanol group, serum urea, creatinine, uric acid, and total lipid levels; liver and intestine LDH; liver MPO, AST, ALP, ALT, and GGT activities; and liver and intestine LPO levels increased, whereas serum CAT activity, liver and intestine GSH levels, and CAT, SOD, and GP(x) activities decreased. On the other hand, treatment with vitamin C, vitamin E, and Se reversed these effects. As a result of these findings, we can say that the combination of vitamin C, vitamin E, and selenium has a protective effect on ethanol-induced changes in lipid peroxidation, glutathione levels, and antioxidant enzyme activities in liver and intestine tissues, and in some serum parameters of rats.

The deleterious effects of ethanol in senescence-accelerated prone 8 mice (SAMP8) and the protective role of nicotinamide (NAM) against ethanol-induced liver injury were examined. The mice were orally administered 2 g ethanol/kg BW and 200 mg or 500 mg NAM/kg BW three times/week for 10 weeks. Results showed that ethanol elevated activity of alanine aminotransferase (ALT) significantly. Ethanol also enhanced the formation of malondialdehyde (MDA) and protein carbonyls in the liver, whereas ethanol treatment resulted in significantly lower activity of hepatic glutathione peroxidase (GPx), catalase and superoxide dismutase (SOD). Hematoxylin and eosin staining indicated moderate to severe fatty infiltration but not fibrosis. Administration of high NAM (500 mg/kg BW) led to markedly decreased levels of hepatic MDA, protein carbonyls, fatty infiltration and the activity of ALT, and increased activity of GPx, catalase and SOD in the ethanol-fed group. Thus, using SAMP8 as animal model for ethanol-induced liver injury in the aged mice, this study demonstrates that NAM is effective in protecting such damage.

To evaluate the cytotoxic effects of chronic ethanol consumption on brain cerebral synaptosomes and preventive role of betaine as a methyl donor and S-adenosylmethionine precursor, 24 male Wistar rats were divided into three groups: control, ethanol (8 g/kg/day) and ethanol plus betaine(0.5% w/v) group. Animals were fed 60 ml/diet per day for two months, then sacrificed. Malondialdehyde (MDA), protein carbonyl contents and adenosine deaminase (ADA) activities were determined in synaptosomal/mitochondrial enriched fraction isolated from rat cerebral cortexes. When compared to controls, ethanol containing diet significantly increased MDA levels (P < 0.05), also increased protein carbonyl levels and adenosine deaminase activities. But these were not statistically significant (P > 0.05). However, adding betaine to ethanol containing diet caused a significant decrease in MDA, protein carbonyl levels and adenosine deaminase activities (P < 0.05). These results indicate that betaine may appear as a protective nutritional agent against cytotoxic brain damage induced by chronic ethanol consumption.

To evaluate chronic ethanol toxicity on erythrocyte membrane and preventive action of betaine as a methyl donor, 24 male Wistar albino rats were divided into three groups: control, ethanol and ethanol plus betaine group. Animals were fed 60 ml diet per day for two months. Rats in the ethanol group were fed ethanol 8 g/kg/day. The ethanol + betaine groups were fed ethanol plus betaine (0.5% w/v). After two months, all animals were killed. Malondialdehyde (MDA) and sialic acid (SA) levels were determined in plasma samples. Osmotic fragility tests were performed on whole blood samples and erythrocyte membrane thiol contents were determined using membrane suspensions. Plasma MDA levels in ethanol-given rats were increased significantly compared to the control group of rats (p < 0.05). MDA in the betaine group was significantly lower than that in the ethanol group (p < 0.05). Erythrocyte membrane thiol contents in ethanol group were decreased compared with those of the control group (p < 0.05). Thiol contents were increased slightly after betaine therapy, but this increase was not statistically significant (p > 0.05). Plasma sialic acid levels in the ethanol group were significantly higher than in the control group (p < 0.05). Sialic acid was decreased in the betaine group compared to the ethanol group (p < 0.05). In the osmotic fragility test, we observed that chronic ethanol consumption increased erythrocyte hemolysis. Betaine protected against ethanol-induced hemolysis. Our findings show that chronic ethanol administration affects erythrocyte membrane properties and this may be related to oxidative stress. Betaine protects erythrocyte membrane alterations against chronic ethanol toxicity. Therefore betaine as a nutritional agent, may protect ethanol induced clinical problems associated with membrane abnormalities.

Previous studies from our laboratory have shown that ethanol consumption results in an increase in hepatocellular S-adenosylhomocysteine levels. Because S-adenosylhomocysteine is a potent inhibitor of methylation reactions, we propose that increased intracellular S-adenosylhomocysteine levels could be a major contributor to ethanol-induced pathologies. To test this hypothesis, hepatocytes isolated from rat livers were grown on collagen-coated plates in Williams' medium E containing 5% FCS and exposed to varying concentrations of adenosine in order to increase intracellular S-adenosylhomocysteine levels. We observed increases in caspase-3 activity following exposure to adenosine. This increase in caspase activity correlated with increases in intracellular S-adenosylhomocysteine levels and DNA hypoploidy. The adenosine-induced changes could be significantly attenuated by betaine administration. The mechanism of betaine action appeared to be via the methylation reaction catalyzed by betaine-homocysteine-methyltransferase. To conclude, our results indicate that the elevation of S-adenosylhomocysteine levels in the liver by ethanol is a major factor in altering methylation reactions and in increasing apoptosis in the liver. We conclude that ethanol-induced alteration in methionine metabolic pathways may play a crucial role in the pathologies associated with alcoholic liver injury and that betaine administration may have beneficial therapeutic effects.

Human whole-blood was exposed to 137Cs gamma-rays or 50 keV/microm carbon ions in the presence or absence of glycine betaine, a beer component in vitro. The dicentrics of chromosome aberrations in human lymphocytes were significantly (p < 0.05) reduced by glycine betaine after irradiation with 4 Gy of either gamma-rays or carbon ions. The maximum protection by glycine betaine for gamma-rays or carbon ions was 37% and 20%, respectively. C3H/He female mice, aged 14 weeks, received an i.p. injection of glycine betaine 15 min before whole-body irradiation with gamma-rays or 50 keV/microm carbon ions. Glycine betaine significantly (p < 0.05) increased the percent survival of irradiated mice with either gamma-rays or carbon ions. In conclusion, glycine betaine is a potent protector against damages caused by low- and high-LET radiation.

Previous studies showed that chronic ethanol administration alters methionine metabolism in the liver, resulting in increased intracellular S-adenosylhomocysteine (SAH) levels and increased homocysteine release into the plasma. We showed further that these changes appear to be reversed by betaine administration. This study compared the effects of betaine and S-adenosylmethionine (SAM), another methylating agent, on ethanol-induced changes of methionine metabolism and hepatic steatosis. Wistar rats were fed ethanol or control Lieber-Decarli liquid diet for 4 wk and metabolites of the methionine cycle were measured in isolated hepatocytes. Hepatocytes from ethanol-fed rats had a 50% lower intracellular SAM:SAH ratio and almost 2-fold greater homocysteine release into the media compared with controls. Supplementation of betaine or SAM in the incubation media increased this ratio in hepatocytes from both control and ethanol-fed rats and attenuated the ethanol-induced increased hepatocellular triglyceride levels by approximately 20%. On the other hand, only betaine prevented the increase in generation of homocysteine in the incubation media under basal and methionine-loaded conditions. SAM can correct only the ratio and the methylation defects and may in fact be detrimental after prolonged use because of its propensity to increase homocysteine release. Both SAM and betaine are effective in increasing the SAM:SAH ratio in hepatocytes and in attenuating hepatic steatosis; however, only betaine can effectively methylate homocysteine and prevent increased homocysteine release by the liver.

This article reviews the reported phytochemical, pharmacological and toxicological properties of Hibiscus sabdariffa L. (English: roselle, red sorrel; Arabic: karkade), the calyces of which are used in many parts of the world to make cold and hot drinks. Nutritionally, these contain ascorbic acid (vitamin C). In folk medicine, the calyx extracts are used for the treatment of several complaints, including high blood pressure, liver diseases and fever. The pharmacological actions of the calyx extracts include strong in vitro and in vivo antioxidant activity. In rats and rabbits, the extract showed antihypercholesterolaemic, antinociceptive and antipyretic, but not antiinflammatory activities. In rat and man a strong antihypertensive action has been demonstrated. The effects of the calyx extracts on smooth muscles in vitro are variable, but they mostly inhibit the tone of the isolated muscles. In healthy men, consumption of H. sabdariffa has resulted in significant decreases in the urinary concentrations of creatinine, uric acid, citrate, tartrate, calcium, sodium, potassium and phosphate, but not oxalate. Oil extracted from the plant's seeds has been shown to have an inhibitory effect on some bacteria and fungi in vitro. The plant extracts are characterized by a very low degree of toxicity. The LD50 of H. sabdariffa calyx extract in rats was found to be above 5000 mg/kg. A single report has suggested that excessive doses for relatively long periods could have a deleterious effect on the testes of rats. In view of its reported nutritional and pharmacological properties and relative safety, H. sabdariffa and compounds isolated from it (for example, anthocyanins and Hibiscus protocatechuic acid) could be a source of therapeutically useful products.

Betaine is distributed widely in animals, plants, and microorganisms, and rich dietary sources include seafood, especially marine invertebrates ( approximately 1%); wheat germ or bran ( approximately 1%); and spinach ( approximately 0.7%). The principal physiologic role of betaine is as an osmolyte and methyl donor (transmethylation). As an osmolyte, betaine protects cells, proteins, and enzymes from environmental stress (eg, low water, high salinity, or extreme temperature). As a methyl donor, betaine participates in the methionine cycle-primarily in the human liver and kidneys. Inadequate dietary intake of methyl groups leads to hypomethylation in many important pathways, including 1) disturbed hepatic protein (methionine) metabolism as determined by elevated plasma homocysteine concentrations and decreased S-adenosylmethionine concentrations, and 2) inadequate hepatic fat metabolism, which leads to steatosis (fatty accumulation) and subsequent plasma dyslipidemia. This alteration in liver metabolism may contribute to various diseases, including coronary, cerebral, hepatic, and vascular diseases. Betaine has been shown to protect internal organs, improve vascular risk factors, and enhance performance. Databases of betaine content in food are being developed for correlation with population health studies. The growing body of evidence shows that betaine is an important nutrient for the prevention of chronic disease.

We investigated the effect of betaine supplementation on ethanol induced steatosis and alterations in prooxidant and antioxidant status in the liver of guinea pigs. Animals were fed with normal chow or betaine containing chow (2% w/w) for 30 days. Ethanol (3 g/kg, i.p.) was given for the last 10 days. We found that ethanol treatment caused significant increases in plasma transaminase activities, hepatic triglyceride and lipid peroxide levels. Significant decreases in glutathione (GSH), alpha-tocopherol and total ascorbic acid (AA) levels were also observed, but hepatic superoxide dismutase, glutathione peroxidase and glutathione transferase activities remained unchanged as compared with those in controls. Betaine treatment together with ethanol in guinea pigs is found to decrease hepatic triglyceride, lipid peroxide levels and serum transaminase activities and to increase GSH levels. No changes in alpha-tocopherol and total AA levels and antioxidant enzyme activities were observed with betaine treatment in alcohol treated guinea pigs. In addition, histopathological assessment of guinea pigs showed that betaine reduced the alcoholic fat accumulation in the liver. Based on these data, betaine treatment has a restoring effect on the alterations in triglyceride, lipid peroxide and GSH levels following ethanol ingestion.

The protective effects of glutathione monoester (GME) on buthionine sulfoximine (BSO)-induced glutathione (GSH) depletion and its sequel were evaluated in rat erythrocyte/erythrocyte membrane. Animals were divided into three groups (n=6 in each): control, BSO and BSO+GME group. Administration of BSO, at a concentration of 4 mmol/kg bw, to the albino rats resulted in depletion of blood GSH level to about 59%. GSH was elevated several folds in the GME group as compared to the control (P<0.05) and BSO (P<0.001) groups. Decreased concentration of vitamin E was found in the erythrocyte membrane isolated from BSO-administered animals. Antioxidant enzymes, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX) were also found to be altered due to BSO-induced GSH depletion in blood erythrocytes. The SOD and CAT activities in BSO group were significantly lower (P<0.001) than the other groups. Lipid peroxidation index and malondialdehyde (MDA) levels in erythrocytes and their membranes were increased to about 45% and 40%, respectively. The activities of Ca2+ ATPase, Mg2+ ATPase and Na+K+ ATPase were lower than those of control group (P<0.05), whereas the activities of these enzymes were found to be restored to normal followed by GME therapy (P<0.05). Cholesterol, phospholipid and C/P ratio and some of the phospholipid classes like phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and sphingomyelin were significantly (P<0.05) altered in the erythrocyte membranes of BSO-administered rats compared with those of control group. These parameters were restored to control group levels in GME-treated group. Oxidative stress may play a major role in the BSO-mediated gamma glutamyl cysteine synthetase (gamma-GCS) inhibition and hence the depletion of GSH. In conclusion, our findings have shown that antioxidant status decreased and lipid peroxidation increased in BSO-treated rats. GME potentiates the RBC and blood antioxidant defense mechanisms and decreases lipid peroxidation.

Hepatic steatosis may have a generally benign prognosis, either because most hepatocytes are not significantly injured or mechanisms to replace damaged hepatocytes are induced. To determine the relative importance of these mechanisms, we compared hepatocyte damage and replication in ethanol-fed and ob/ob mice with very indolent fatty liver disease to that of healthy control mice and PARP-1(-/-) mice with targeted disruption of the DNA repair enzyme, poly(ADP-ribose) polymerase. Compared to the healthy controls, both groups with fatty livers had significantly higher serum alanine aminotransferase values, hepatic mitochondrial H(2)O(2) production, and hepatocyte oxidative DNA damage. A significantly smaller proportion of the hepatocytes from fatty livers entered S phase when cultured with mitogens. Moreover, this replicative senescence was not reversed by treating cultured hepatocytes with agents (i.e., betaine or leptin) that improve liver disease in intact ethanol-fed or leptin-deficient mice. Hepatocytes from PARP1(-/-) mice also had more DNA damage and reduced DNA synthesis in response to mitogens. However, neither mice with fatty livers nor PARP-1-deficient mice had atrophic livers. All of the mice with senescent mature hepatocytes exhibited hepatic accumulation of liver progenitor (oval) cells and oval cell numbers increased with the demand for hepatocyte replacement. Therefore, although hepatic oxidant production and damage are generally increased in fatty livers, expansion of hepatic progenitor cell populations helps to compensate for the increased turnover of damaged mature hepatocytes. In conclusion, these results demonstrate that induction of mechanisms to replace damaged hepatocytes is important for limiting the progression of fatty liver disease.

To observe the changes in the antioxidative defense enzymes and to detect the alterations of renal microscopy after carbon tetrachloride (CCl4) administration in rats and to investigate the possible protective effects of betaine against CCl4-induced renal damage.

Thirty-two adult Sprague-Dawley rats were divided into four groups as follows: control group, betaine group, CCl4 group, and CCl4 + betaine group. CCl4 was given subcutaneously at 1 mL/kg. In the CCl4 + betaine group, rats were pretreated with betaine, then exposed to CCl4 at the same dose. Betaine group rats received concentrated betaine solution. The rats were killed and the kidneys taken for enzyme analyses and histologic examination. Glutathione peroxidase, superoxide dismutase, and catalase activities were measured in right kidney homogenates. Left kidneys were processed for light microscopic evaluation.

In the CCl4-treated group, significant increases in kidney superoxide dismutase and catalase activities and significant decrease in glutathione peroxidase activity were observed (P <0.01). These changes were found to be normalized in the CCl4 + betaine group. Betaine did not change the enzyme activities. Exposure to CCl4 resulted in glomerular and tubular alterations in the renal cortex. These alterations were found to be prevented by betaine pretreatment.

These results indicate that exposure to CCl4 leads to renal damage in rats and betaine exerts an improvement on nephrotoxic effects of CCl4.

Bile acid-induced apoptosis plays an important role in the pathogenesis of cholestatic liver disease, and its prevention is of therapeutic interest. The effects of betaine were studied on taurolithocholate 3-sulfate (TLCS) and glycochenodeoxycholate (GCDC)-induced apoptosis in rat hepatocytes in vitro and in vivo. Hepatocyte apoptosis, caspase activation, and poly (ADP-ribose) polymerase (PARP) cleavage, which are normally observed in response to both bile acids, were largely prevented after preincubation of hepatocytes with betaine. Betaine uptake was required for this protective effect, which was already observed at betaine concentrations of 1 mmol/L. Betaine did not affect the TLCS-induced membrane trafficking of CD95 and tumor necrosis factor-related apoptosis inducing ligand (TRAIL) receptor 2 to the plasma membrane or the TLCS-induced recruitment of Fas-associated death domain (FADD) and caspase 8 to the CD95 receptor. However, betaine largely prevented cytochrome c release and oxidative stress exerted otherwise by TLCS. Inhibition of caspase 9 strongly blunted TLCS-induced caspase-8 activation. Further betaine did not prevent the TLCS-induced c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (Erk), and p38 mitogen-activated protein kinase (p38(MAPK)) activation or TLCS-induced protein kinase B (PKB) dephosphorylation. The protective betaine effect was insensitive to inhibition of Erks by PD089059, of p38(MAPK) by SB203580, or of phosphatidylinositol 3-kinase (PI3-kinase) by LY294002. Betaine supplementation in the drinking water significantly ameliorated in vivo hepatocyte apoptosis following bile duct ligation. In conclusion, this study identifies betaine as a potent protectant against bile acid-induced apoptosis in vivo and in vitro, and its antiapoptotic action largely resides on an inhibition of the proapoptotic mitochondrial pathway.