Effect of Ethanolic Stem Bark Extract of Blighia unijugata (Sapindaceae) on Monosodium Glutamate-Induced Uterine Leiomyoma in Sprague-Dawley Rats

Abstract

Aims: To establish the presence of monosodium glutamate (MSG) as an ingredient of artificial food seasonings on the Ghanaian market, and to evaluate the anti-fibroid property of an ethanolic stem bark extract of Blighia unijugata on MSG-induced uterine leiomyoma in Sprague-Dawley rats and its safety for use. Study Design: Survey and Experimental. Place and Duration of Study: Department of Pharmacology, CHS; September 2012 and May 2013. Methodology: A survey was conducted to ascertain MSG as an ingredient of Food and Drugs Board approved artificial food seasonings on the Ghanaian Market. Phytochemical screening was performed on an ethanolic, aqueous, and petroleum ether extract of B. unijugata. Thin layer and high performance liquid chromatographic analysis were performed on the ethanolic extract of B. unijugata (EBU), selected after phytochemical screening, to obtain fingerprint chromatograms for identification. Preventive and curative studies (measuring total plasma cholesterol and plasma estradiol and uterus weight) using 50 and 100 mg kg-1 EBU, per os, on 600 and 800 mg kg-1 MSG-induced uterine leiomyoma in Sprague-Dawley rats was conducted. Acute and Delayed toxicity on EBU was tested. Results: Of 21 FDB approved artificial food seasonings, 85.7% had MSG as an ingredient. MSG administration to rats elevated significantly (P ≤ .001) cholesterol, estradiol and uterus weight and size (indicating hyperplasia). Curative treatment reduced significantly (P ≤ .01-.001) the elevated plasma cholesterol and estradiol than preventive treatment. Both treatments however significantly decreased (P ≤ .01-.001) elevated uterus weight. The lethal dose was less than 1000 mg kg-1 p.o. Conclusion: MSG is found in almost all artificial food seasoning on the Ghanaian market which could be a risk factor to the development of uterine leiomyoma. The ethanolic extract of Blighia unijugata reversed hyperplasia induced in the uterus by MSG, making it useful as an anti-fibroid drug.