Asian Pacific Journal of Tropical Biomedicine

97-104

Authors: Jarinyaporn Naowaboot, Urarat Nanna, Linda Chularojmontri, Pholawat Tingpej, Patchareewan Pannangpetch

Objective: To examine the effect of water extract of Thunbergia laurifolia on hepatic insulin resistance in high-fat diet-induced obese mice. Methods: High-fat diet with 45 kcal% lard fat was used for obesity induction in ICR mice. The mice were fed with high-fat diet for 16 weeks, and during the last 8 weeks, they were treated with 200 mg/ kg/day of water extracts from Thunbergia laurifolia leaf, stem and flower. Serum biochemistry, liver histology, and protein expression were examined after the treatment. Results: Extracts from all of the three parts of Thunbergia laurifolia significantly alleviated hyperglycemia, hyperlipidemia, hyperinsulinemia, and hyperleptinemia. The stem and flower extracts improved glucose tolerance. All of the extracts significantly reduced serum TNFα and monocyte chemoattractant protein-1 levels. Liver weight, triglyceride levels, and lipid accumulation were also decreased. Moreover, hepatic glucose-6-phosphatase level was significantly decreased, while the levels of PPARα, phosphorylated AMPK, and phosphorylated Akt were significantly increased with treatment of Thunbergia laurifolia extracts. Conclusions: Thunbergia laurifolia extracts can ameliorate hepatic insulin resistance in high-fat diet-induced obese mice by improving glucose and lipid homeostasis, which may be associated with stimulating phosphorylation of AMPK and Akt pathways.

115-121

Authors: Zeinab Rafiee, Maasoumeh Zare Moaiedi, Armita Valizadeh Gorji, Esrafil Mansouri

Objective: To evaluate the effect of p-coumaric acid against adriamycin-induced hepatotoxicity in rats. Methods: The rats were divided into 4 groups. The control group received solvent; the p-coumaric acid group was treated with 100 mg/kg of p-coumaric acid orally for five consecutive days; the adriamycin group was administered with a single dose of adriamycin (15 mg/kg, i.p.), and the p-coumaric acid + adriamycin group was given p-coumaric acid five days before adriamycin administration. Twenty-four hours after the last administration, blood samples were collected for biochemical analysis, and liver tissues were removed for histopathological and immunohistochemistrical studies. Moreover, the levels of tissue lipid peroxidation and enzyme activities of glutathione peroxidase, superoxide dismutase, and catalase in liver tissue were measured. Results: Treatment with p-coumaric acid protected the liver from the toxicity of adriamycin by attenuating the increase in alkaline phosphatase, alanine transaminase, aspartate transaminase, total bilirubin, total cholesterol, triglyceride, and low-density lipoprotein cholesterol and lessening the decrease in high-density lipoprotein cholesterol and albumin. p-Coumaric acid also raised the levels of glutathione peroxidase, superoxide dismutase, and catalase, as well as decreased lipid peroxidation in liver tissue and hepatic IL- 1β expression. Additionally, histopathological study confirmed the protective effect of p-coumaric acid against liver damage. Conclusions: p-Coumaric acid can alleviate adriamycin-induced hepatotoxicity.

132-140

Authors: Koloko Brice Landry, Shafiq Azam, Sidra Rehman, Somayya Tariq, Bushra Iqbal, Mateen Abbas, Dieudonné Massoma Lembè, Bushra Ijaz

Objective: To evaluate the antiviral activity and phytochemicals of selected plant extracts and their effect on the mitogen-activated protein kinase (MAPK) signaling pathway modulated by hepatitis C virus (HCV) nonstructural protein 5A (NS5A). Methods: A total of ten plant extracts were initially screened for their toxicities against HepG2 cells. The non-toxic plants were tested for their inhibitory effect on the expression of HCV NS5A at both mRNA and protein levels using real-time PCR and Western blotting assays, respectively. The differential expression of the genes associated with MAPK pathway in the presence of NS5A gene and plant extract was measured through real-time PCR. Subsequently, the identification of secondary metabolites was carried out by phytochemical and HPLC analysis. Results: The phytochemical profiling of Berberis lyceum revealed the presence of alkaloids, phenols, saponins, tannins, flavonoids, carbohydrates, terpenoids, steroids, and glycosides. Similarly, quercetin, myricetin, gallic acid, caffeic acid, and ferulic acid were identified through HPLC analysis. The methanolic extract of Berberis lyceum strongly inhibited HCV RNA replication with an IC50 of 11.44 µg/mL. RT-PCR and Western blotting assays showed that the extract reduced the expression of HCV NS5A in a dose- dependent manner. Berberis lyceum extract also attenuated NS5A- induced dysregulation of the MAPK signaling pathway. Conclusions: Our findings suggest that Berberis lyceum extract strongly inhibits HCV propagation by reducing HCV NS5A- induced perturbation of MAPK signaling.