RESUMEN
Background: Artesunate (ART) is a semi-synthetized molecule from Artemisinin, an active compound isolated from the medicinal plant Artemisia annua, widely used for the treatment of malaria. Previous studies reported that ART may exert a dual effect on the liver. Accordingly, this study investigated the potential protective action of ART against Acetaminophen (APAP) and Carbon tetrachloride (CCl4)-induced hepatotoxicity in primary mice hepatocytes, in comparison to that of flavonoid extracted from A. annua (FAA). In addition, the antioxidant properties of FAA were also assessed. Methods: The antioxidant activities of FAA and Ascorbic acid (ASC) (0.01-100 µg/mL) were assessed through inhibition of lipid peroxidation, reduction of ferric and phosphomolydenum, and hydroxyl and DPPH radicals scavenging assays. The hepatoprotective effects of FAA and ART (0.1-100 µg/mL) were evaluated against APAP (11 mM) or CCl4 (4 mM) induced oxidative damage in primary mouse hepatocytes. Biochemical parameters associated with hepatotoxicity assessed include cell viability, cell membrane integrity, cellular glutathione, and antioxidant enzyme activities. Results: The obtained finding revealed FAA displayed a remarkable antioxidant activities as evidenced by the low IC50/EC50 values (3.85-19.32 µg/mL), comparable to that of ASC (3.26-18.04 µg/mL). When tested at 10 µg/mL, both FAA and ART significantly (pË0.05) preserved cell viability, inhibited alanine aminotransferase leakage and lipid membrane peroxidation, and restored superoxide dismutase and catalase activities and glutathione content induced by APAP or CCl4 in a similar way as Silymarin. However, ART showed a significant (pË0.05) cytotoxic effect on hepatocytes at 100 and 1000 µg/mL and did not confer obvious protection at 100 µg/mL. Conclusion: Overall, our data demonstrated that ART harms mice hepatocytes at high concentration while conferring relative protection against APAP and CCl4-hepatotoxicity at low concentration. In contrast, FAA effectively protects liver cells without cytotoxicity effect, event at 100 µg/mL. Accordingly, ART should be given to the patient only under a medical prescription.
RESUMEN
People living in developing countries are exposed to hepato-renal injuries induced by heavy metals like lead (Pb), cadmium (Cd), and mercury (Hg) since drinking water supplied is often polluted with a high concentration of those metals. Accordingly, it is necessary to search for antidotes against heavy metals poisoning. Hence, medicinal plants bearing anti-hepatotoxic properties represent a credible option; and such plant is Khaya grandifoliola. However, there is a paucity of knowledge regarding its protective effect on heavy metals-induced hepato-renal toxicity. Thus, this study was designed to assess the protective effect of the hydro-ethanolic stem bark extract of K. grandifoliola (HKG) against hepato-renal injuries induced by chronic consumption of drinking water containing high contents of Pb, Cd, and Hg; in addition to the investigation of the chemical antioxidant properties of HKG. For the antioxidant assays, HKG was tested as a potential inhibitor of lipid peroxidation, reducer of ferric and phosphomolybdenum, and scavenger of hydroxyl and 2,2-Diphenyl-Picryl-Hydrazyl radicals. Its protective effects were evaluated by daily co-treating rats with heavy metals solution (10 mL/kg b.w) containing 0.9, 0.58, and 1.13 ppm respectively for Pb, Cd and Hg and HKG (25 or 100 mg/kg b.w) for five consecutive months; and biochemical parameters associated to liver and kidneys functions, oxidative stress and metals bioaccumulation were assessed. HKG displayed a strong antioxidant capacity (IC50/EC50 range 3.95-17.17 µg/mL) correlated to its polyphenols content and comparable to that of Ascorbic acid. Serum levels of alkaline phosphatase, alanine/aspartate aminotransferase, and creatinine; renal and hepatic content of Cd and Pb, malondialdehyde and glutathione, activities of superoxide dismutase and catalase showed the protective effect of HKG, further evidenced by histopathological analysis. Taking together, these results demonstrated that HKG alleviates heavy metals-induced hepato-renal injuries in rats by reducing oxidative stress and metals-bioaccumulation.
RESUMEN
OBJECTIVE: A fraction from Khaya grandifoliola has recently been shown to inhibit hepatitis C virus (HCV) infection and three limonoids (17-epi-methyl-6-hydroxylangolensate, 7-deacetoxy-7-oxogedunin and 7-deacetoxy-7R-hydroxygedunin) were purified from this fraction. The present study aimed at assessing the inhibitory effect of these limonoids on HCV using cell-culture derived HCV (HCVcc) system. MATERIALS AND METHODS: Cytotoxic effects of the limonoids on Huh7.5 cells were assessed by MTT assay. Huh7.5 cells were transfected with RNA transcripts of the plasmid Jc1/GLuc2a, carrying a Gaussia luciferase reporter gene to rescue the HCVcc particles which were used to infect naïve cells in the presence or absence of the studied limonoids during 72 hr. Infection and replication rates were monitored by luciferase reporter assay and immunofluorescence assay (IFA) while cellular gene expression was analyzed by western blot, respectively. RESULTS: The limonoids inhibited HCV infection mostly by targeting entry and replication stage. Their inhibitory effect on entry step, comparable to that of anti-CD81 antibody, was related to the blocking of CD81 receptor. In the replication step, the limonoids decreased the expression of NS5B similar to danoprevir. These compounds also significantly decreased but up-regulated the expression of Class-III phosphatidylinositol 4-kinase alpha and 2',5'-oligoadenylate synthase-3, respectively. CONCLUSION: The present findings suggest that limonoids from K. grandifoliola are potential anti-HCV agents and may offer an advantage in the treatment of HCV infection.
RESUMEN
Entada africana is used in non-conventional medicine for the management of liver ailments. A fraction, designated EaF10 (methylene chloride/methanol 90:10, v/v) with promising hepatoprotective activity has been isolated. Since the mechanisms underlying EaF10 hepatoprotective action remain unknown, this study was undertaken to investigate the anti-hepatotoxic mechanism of the fraction against carbon tetrachloride (CCl4)-induced hepatotoxicity and its antioxidant properties. Antioxidant activities of EaF10 were assessed through four chemical antioxidant assays and its anti-hepatotoxic effect evaluated in vivo and in vitro by post-treatment (25 or 100 mg/Kg) or co-treatment (6.25-100 µg/mL) in CCl4-intoxicated mice and normal human liver cells line L-02 hepatocytes respectively; and biochemical and molecular parameters assessed respectively by spectrophotometry, and by quantitative real-time polymerase chain reaction and western blot analysis. EaF10 exhibited strong antioxidant activities correlated with its polyphenol content. Serum levels of alanine/aspartate aminotransferase (AST/ALT) and nitrite oxide, liver contents of glutathione (GSH) protein carbonylation and malondialdehyde (MDA), liver activities of catalase (CAT), glutathione-S-transferase (GST) and superoxide dismutase (SOD) and cell viability showed the anti-hepatotoxic effect of EaF10, supported by histopathological observations. The fraction decreased the protein level of Cytochrome P450 2E1 (CYP2E1) and Kelch-like ECH-associated protein-1 (Keap-1), induced nuclear translocation of Nuclear factor-erythroid 2-related factor-2 (Nrf2) coupled to an increase of the mRNA levels of CAT, SOD1 and GST in CCl4-intoxicated L-02 hepatocytes. These findings evidenced that the studied plant fraction possesses a strong antioxidant capacity and prevents CCl4-induced hepatotoxicity, likely through inhibition of CYP2E1 and activation of the Nrf2 signaling pathway.
RESUMEN
BACKGROUND: Khaya grandifoliola (Meliaceae) and Entada africana (Fabaceae) are traditionally used in Bamun (a western tribe of Cameroon) traditional medicine for the treatment of liver related diseases. In this study, the synergistic hepatoprotective effect of respective active fractions of the plants were investigated against paracetamol-induced toxicity in primary cultures of rat hepatocytes. METHODS: Paracetamol conferred hepatocyte toxicity, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, alanine aminotransferase (ALT), superoxide dismutase (SOD), catalase (CAT) activities, malondialdehyde (MDA) and glutathione (GSH) content assays. The crude extracts were fractionated by flash chromatography and fractions were tested for hepato-(protective and curative) activities. The most active fractions of both plants were tested individually, and in combination based on their respective half effective concentration (EC50). RESULTS: The methylene chloride/methanol fractions of K. grandifoliola (75:25 v/v) (KgF25) and E. africana (90:10 v/v) (EaF10) were found to be the most hepato-protective with EC50 values of 10.30 ± 1.66 µg/ml and 13.47 ± 2.06 µg/ml respectively, comparable with that of silymarin (13.71 ± 3.87 µg/ml). These fractions and their combination significantly (P <0.05) improved cell viability, inhibited ALT leakage and MDA formation, and restored cellular CAT, SOD activities and GSH content. The combination was more effective in restoring biochemical parameters with coefficients of drugs interaction (CDI) less than 1. CONCLUSION: These findings demonstrate that the active fractions have synergistic action in the protection of rat hepatocytes against paracetamol-induced damage and suggest that their hepatoprotective properties may be maximized by using them in combination.