Effects of roasted beef based-diet on thyroid hormones and vitamins: The biochemical roles of lycopersicon esculentum L. and Allium cepa

Abstract

In this 21 days study, two biomarkers- thyroid hormones and vitamins were used to evaluate the hormonal disruptive potentials of locally processed beef and the protective effects of ethyl acetate and methanol extracts of Lycopersicon esculentum L. and Allium cepa respectively. Twenty five male rats (168.8±13.05 g) were divided into 5 groups of 5 rats each. Feed was formulated with 15% w/w of processed beef. Group I (control) rats were fed rat pellets (RP) only, group II received formulated diet (FD) only, group III and IV received FD and 500 mg/kg bw of A. cepa and L. esculentum L. extracts respectively and group V received FD 250 mg/kg bw each of A. cepa and L. esculentum L extracts. Serum concentrations of thyroxine (T4), triiodothyronine (T3), and thyroid stimulating hormone (TSH) were determined by an ELISA method used for quantitative in-vitro determinations. Vitamins were determined spectrophotometrically. Significant (P < 0.05) disturbances in serum T3, T4 and TSH concentration were observed in rats exposed to formulated diet only when compared to the control. However, none significant (P < 0.05) changes in thyroid hormones concentration were observed in groups administered the extracts, compared to the control. There were also, significant (P < 0.05) decrease in concentrations of vitamins A, C, D and E in FD group when compared to RP groups or groups administered either of the extracts or the combination. This study indicates that, these disturbances which could result to adverse biochemical and physiological consequences could be ameliorated if consumers of roasted beef avail themselves of the chemoprotective potentials of L. esculentum L. and A. cepa sauce.