To investigate the potential activity of Bombyx mori
and its formulations against isoproterenol
(ISO) induced cardiotoxicity.
Wistar rats were orally pretreated with the ethanol extract of Bombyx mori
cocoons in two
doses (250 and 500 mg/kg) for 30 days; rats were similarly pretreated with its polyherbal formulations
incorporating Khamira Abresham sada (KAS) and Khamira Abresham Hakim Arshadwala (KAHAW)
(800 mg/kg), standard drug metoprolol (10 mg/kg) and normal saline for 30 days. Cardiotoxicity was
induced by administration of isoproterenol (ISO, 85 mg/kg, subcutaneous) given twice on days 29 and
30 in all six pre-treated groups (n = 6) except the normal control. Cardiotoxicity was assessed by
morphological and biochemical evaluation and further confirmed by histopathological studies.
Pretreatment with Bombyx mori
(500 mg/kg), KAHAW and KAS significantly decreased (p <
0.01) the heart weight:body weight (HW:BW) ratio; significantly decreases the elevated activities of the
cardiac marker enzymes, namely, asparate transaminase (AST) (p < 0.01), alanine transaminase (ALT)
(p < 0.01), lactate dehydrogenase (LDH) (p < 0.01) ,creatinine kinase (CK-MB) (p < 0.01) and
thiobarbituric acid reactive substances (TBARS) (p < 0.01) similar to the standard drug metoprolol (p <
0.01) in ISO-injected rats. Pre-treatment of rats with Bombyx mori
(500 mg/kg), KAS, KAHAW and
metoprolol challenged with ISO also showed absence of troponin. Pretreatment with B. mori
mg/kg), KAHAW and KAS significantly increased the activities of Superoxide dismutase (SOD) (p <
0.01), Tissue glutathione (GSH) (p < 0.01) and catalase (p < 0.01) similar to the standard drug
metoprolol (p < 0.01).
The findings of this study indicate that Bombyx mori
as well as its polyherbal formulations
exerts potent cardioprotection against isoproterenol-induced cardiotoxicity. This effect is comparable
with that of metoprolol.