The Toxicity Test of Momordica charantia L. Seed Protein.

Abstract

The seed of the ripened fruit of Momordica charantia L. (Thai bitter gourd) contains an important protein named MRK29. This protein can inhibit the HIV-1 reverse transcriptase. When the concentration is increased it can also reduce the viral core protein p24 expression in HIV infected cells. It is possible to develop an anti-HIV drug from MRK29.

The objective of this research was to study the acute and subchronic toxicity of Momordica seed protein. In acute toxicity tests, the Momordica seed protein was administered intravenously and intraperitoneally into Swiss albino mice and Wistar rats. Following a single dose, the LD₅₀ of Momordica seed protein in the mice and rats was approximately 1 mg/kg (i.v., i.p.). The abnormal signs and symptoms found in mice were bronchoconstriction, depression, and seizure. The abnormal signs and symptoms found in rats were bronchoconstriction, depression, seizure, and a red-black discharge from the eye. In subchronic toxicity tests, the Momordica seed protein was administered daily intrarectally into Wistar rats for three months at doses of 0.25, 0.5, 1, and 2 mg/kg/day. The abnormal signs and symptoms found were diarrhea and death caused by diarrhea. Moreover, 10% of the rats treated with Momordica seed protein at the dose of 0.25 mg/kg/day had an elevation in liver enzymes, i.e. SGOT, SGPT, LDH. But, in higher doses of Momordica seed protein, the level of these enzymes was reduced. The findings were parallel with histological changes in the liver, i.e. higher doses induced more fatty changes. The Momordica seed protein also had an irritating effect on the rectum at the site of drug administration.

In the development of this product to a pharmaceutical dosageform there should be

concern about effect on the liver function and the irritating effect on the rectum of Momordica seed protein. Finally, more toxicological studies on the hepatotoxicity of Momordica seed protein should be performed to establish the safety of this product prior to its usage in humans.