Infused aqueous curry tea extracts ameliorate Nω-Nitro-L-Arginine Methyl Ester-induced liver dysfunction in male albino Wistar rats

Background: Murraya koenigii (L.) Spreng. (Rutaceae) has been reported to positively affect liver function. However, the effect of M. koenigii leaves on N-omega-Nitro-L-Arginine Methyl Ester (L-NAME) induced liver dysfunction is unknown. The aim of the present study was therefore to investigate the effect of M.koenigii leaves as tea on L-NAME induced liver dysfunction. Methods: Two variants of curry tea were formulated; one was formulated entirely from leaves of M. koenigii, the other was formulated with thaumatin-rich aril obtained from seeds of Thaumatococcus danielii (Benn.) Benth. (Marantaceae). Group I animals served as control and were untreated. Groups II and V animals were administered curry tea (CT). Group III and VI animals received curry-thaumatin tea (CTT). Concurrently, L-NAME (40 mg/kg) was administered to groups IV-VI respectively for 21 days. Blood and liver samples were collected at the end of the study for biochemical, histological, and immunohistochemical analysis. Results: L-NAME induced liver dysfunction evidenced by liver histology, increased activities of ALT, AST, hyperlipidemia, hepatic oxidative stress and increased hepatic NF-kB expression. Administration of CT and CTT ameliorated the L-NAME induced liver dysfunction evidenced by liver histology, increased NO hepatic bioavailability, reduced activity of ALT and AST, increased hepatic antioxidant system and decreased hepatic NF-kB expression. Thaumatin taste/flavor enhancer did not significantly reduce or potentiate the hepatoprotective, antioxidant and anti-lipidemic property of aqueous curry tea extracts in rats. Conclusion: L-NAME impaired liver function in rats. CT and CTT interfered with the ability of L-NAME to inhibit NO synthesis which was associated with ameliorated hepatic dysfunction. Practical applications The study reports that non-selective inhibition of nitric oxide by L-NAME in rats impairs liver function and formulated curry tea types interfered with the ability of L-NAME to inhibit NO synthesis which was associated with ameliorated hepatic dysfunction in rats.