Hepatoprotective potential of Phyllanthus muellarianus leaf extract: studies on hepatic, oxidative stress and inflammatory biomarkers.

CONTEXT: Leaves of Phyllanthus muellarianus (Kuntze) Exell. (Euphorbiacea) are widely used in the management of liver disorders in Nigeria. However, no there is no scientific validation to support this use. OBJECTIVE: Hepatoprotective effect of Phyllanthus muellarianus aqueous leaf extract was investigated in acetaminophen-induced liver injury mice. MATERIALS AND METHODS: Hepatoprotective effect of Phyllanthus muellarianus aqueous leaf extract was evaluated in acetaminophen-induced hepatic damage in Swiss albino mice using biomarkers of hepatocellular indices, oxidative stress, proinflammatory factors and lipid peroxidation. Mice received distilled water, 100, 200, or 400 mg/kg b.w of Phyllanthus muellarianus aqueous leaf extract, respectively, for seven days. Treatment groups were challenged with 300 mg/kg b.w of acetaminophen on the sixth day. RESULTS: Oral administration of Phyllanthus muellarianus aqueous leaf extract significantly (p < 0.05) attenuates acetaminophen-mediated alterations in serum alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, albumin and total bilirubin by 76.56, 85.41, 89.39, 82.77 and 78.38%. Similarly, acetaminophen-mediated decrease in activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase were significantly attenuated in the liver of mice by 85.10, 80.81, 80.45, 76.23 and 95.22%, respectively. Increased levels of conjugated dienes, lipid hydroperoxides, malondialdehyde, protein carbonyl, fragmented DNA, tumor necrosis factor-α, interleukin-6 and -8 were significantly lowered by Phyllanthus muellarianus aqueous leaf extract. CONCLUSION: Overall, results of this study show that Phyllanthus muellarianus halted acetaminophen-mediated hepatotoxicity due to its capability to enhance antioxidant enzymes.

Combined administration of silymarin and vitamin C stalls acetaminophen-mediated hepatic oxidative insults in Wistar rats

Oxidative insult by free radicals has been implicated in drug-induced hepatic damage and this has resulted in frequent episodes of liver disorders. Therapeutic efficacy of antioxidants may provide a possible solution to this menace. This study was carried out to investigate the effect of combined administration of silymarin and vitamin C in rescuing acetaminophen-induced hepatotoxicity in rats. Hepatotoxic rats were orally administered with silymarin and vitamin C at 100 and 200 mg/kg body weight, respectively. At the end of the experiment, liver function indices, antioxidant parameters and histological analysis were evaluated. We observed that the significantly increased (p < 0.05) activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, as well as levels of thiobarbituric acid reactive substances and serum total bilirubin, were markedly reduced following co-administration of silymarin and vitamin C. The compounds also effectively reversed the reduced activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and total protein concentration in the hepatotoxic rats. These findings are indicative of hepatoprotective and antioxidant attributes of the two compounds which are also supported by the histological analysis. The available evidences in this study suggest that the complementary effects of silymarin and vitamin C proved to be capable of ameliorating acetaminophen-mediated hepatic oxidative damage and the probable mechanism is via antioxidative action.

Phenolic extract of Parkia biglobosa fruit pulp stalls aflatoxin B1 – mediated oxidative rout in the liver of male rats

The effect of phenolic extract of Parkia biglobosa (Jacq.) R. Br. ex G. Don, Fabaceae, pulp on aflatoxin B1 induced oxidative imbalance in rat liver was evaluated. Thirty-five male rats were randomized into seven groups of five animals each. Rats in group A served as control and received vehicle for drug administration (0.5% DMSO) once daily at 24 h intervals for six weeks. Rats in groups B, D, E, F and G, received aflatoxin B1 (167 μg/kg body weight) in 0.5% DMSO for three weeks, starting from the third week of the experimental period. Rats in Group C received 400 mg/kg bodyweight of the extract for six weeks, while groups D, E and F rats were treated with 100, 200 and 400 mg/kg bodyweight of the extract for six weeks respectively. Group G rats received 100 mg/kg body weight of vitamin C. Aflatoxin B1-mediated decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase were significantly attenuated. Aflatoxin B1 mediated the elevation in malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and significantly lowered DNA fragmentation percentage. Overall, the phenolic extract of P. biglobosa pulp stalls aflatoxin B1-mediated oxidative rout by enhancing antioxidant enzyme activities leading to decreased lipid peroxidation, protein oxidation and DNA fragmentation.

A novel inhibitor of cytokinin degradation (INCYDE) influences the biochemical parameters and photosynthetic apparatus in NaCl-stressed tomato plants.

The effect of 2-chloro-6-(3-methoxyphenyl)aminopurine [inhibitor of cytokinin degradation (INCYDE)] at 10 nM on growth, biochemical and photosynthetic efficiency in sodium chloride (NaCl)-stressed (75, 100 and 150 mM) tomato plants was investigated. NaCl-induced decline in plant vigor index was slightly reversed by both drenching and foliar application of INCYDE. Foliar application of INCYDE significantly increased the flower number in the control and 75 mM NaCl-supplemented plants, while drenching was more effective in 150 mM NaCl-stressed plants. Antioxidant enzymes (peroxidase, catalase and superoxide dismutase) were enhanced in the presence of INCYDE in the control and NaCl-stressed plants. Higher concentration of malondialdehyde (MDA) associated with oxidative (lipid peroxidation) damage in leaf tissue which was evident in the presence of NaCl stress was significantly attenuated with the drenching and foliar application of INCYDE. Regardless of NaCl concentration, application of INCYDE had no significant influence on maximum quantum efficiency of photosystem II. However, the reduced quantum yield of photosystem II and coefficient of photochemical quenching under continuous illumination with actinic light at four intensities (264, 488, 800 and 1,200 µmol m(-2) s(-1)) in NaCl-stressed (100 and 150 mM) tomato plants were significantly alleviated by drenching application with INCYDE. Non-photochemical quenching of the singlet excited state of chlorophyll a and relative electron transfer rate were generally higher in INCYDE-treated plants than in the controls. From an agricultural perspective, these findings indicate the potential of INCYDE in protecting plants against NaCl stress and the possibility of enhanced productivity.

Evaluation of Antidiabetic Activity and Associated Toxicity of Artemisia afra Aqueous Extract in Wistar Rats.

Artemisia afra Jacq. ex Willd. is a widely used medicinal plant in South Africa for the treatment of diabetes. This study aimed to evaluate the hypoglycemic activity and possible toxicity effect of aqueous leaf extract of the herb administered at different dosages for 15 days in streptozotocin-induced diabetic rats. Administration of the extract at 50, 100, and 200 mg/kg body weight significantly (P < 0.05) increased body weight, decreased blood glucose levels, increased glucose tolerance, and improved imbalance in lipid metabolism in diabetic rats. These are indications of antidiabetic property of A. afra with 200 mg/kg body weight of the extract showing the best hypoglycemic action by comparing favourably well with glibenclamide, a standard hypoglycemic drug. The extract at all dosages tested also restored liver function indices and haematological parameters to normal control levels in the diabetic rats, whereas the kidney function indices were only normalized in the diabetic animals administered with 50 mg/kg body weight of the extract. This investigation clearly showed that in addition to its hypoglycemic activity, A. afra may also protect the liver and blood against impairment due to diabetes. However, some kidney functions may be compromised at high dosages of the extract.

The effect of Aloe ferox Mill. in the treatment of loperamide-induced constipation in Wistar rats.

BACKGROUND: Constipation is the most common gastrointestinal complaint all over the world and it is a risk factor of colorectal cancer. In this study, the efficacy of aqueous leaf extract of Aloe ferox Mill. was studied against loperamide-induced constipation in Wistar rats. METHODS: Constipation was induced by oral administration of loperamide (3 mg/kg body weight) while the control rats received normal saline. The constipated rats were treated with 50, 100 and 200 mg/kg body weight/day of the extract for 7 days during which the feeding characteristics, body weight, fecal properties and gastrointestinal transit ratio were monitored. RESULTS: The extract improved intestinal motility, increased fecal volume and normalized body weight in the constipated rats, which are indications of laxative property of the herb with the 200 mg/kg body weight of the extract showing the best efficacy. CONCLUSION: The effect of the extract compares favourably well with senokot, a standard laxative drug. These findings have therefore, lent scientific credence to the folkloric use of the herb as a laxative agent by the people of the Eastern Cape of South Africa.