Cardioprotective and Antilipidemic Effect of Gemmotherapeutically Treated Glycyrrhiza glabra against Isoproterenol Induced Myocardial Injury

Aims: To evaluate preventive (pre- treated) and curative (post treated) potential of gemmomodified and native extract of Glycyrrhiza glabra for alleviating harmful changes in lipid profile (HDL, LDL, TG, TC) and cardiac enzymes (CK-MB, LDH, SGOT, SGPT) against isoproterenol (ISO) induced myocardial injury in rabbits.

Study Design: In vivo study.

Place and Duration of Study: Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad, Pakistan, between February 2011 and April 2011.

Methodology: Thirty six rabbits weighing 1.25 ± 0.2 Kg were allocated into six groups (Control, Ischemia, Gemmo curative, Native curative, Gemmo preventive and Native preventive) having six animals each. Rabbits were fed normal diet for 20 days. Gemmo preventive and Native preventive groups were also given gemmo modified and native extract (100 mg kg-1). On 20th day and 21st day rabbits were given ISO (50 mg kg-1). Five days after the ischemia the Gemmo curative and Native curative groups were given gemmo and native extracts (100 mg kg-1). Serum activities of lipid profile and cardiac enzymes were determined.

Results: ISO administration significantly lowered (P=.05) HDL level and increased (P=.05) LDL, TG and TC as compared with control rabbits. ISO injury significantly increased (P=.05) the levels of cardiac enzymes CK-MB. LDH, SGOT and SGPT as compared with control rabbits. Curative treatment with gemmo and native extracts of Glycyrrhiza glabra significantly increased (P=.05) level of HDL and lowered (P=.05) the level of LDL, TG, TC and cardiac enzymes as compared with ischemic rabbits. Pre treatment with gemmo and native extracts prevented the reduction (P=.05) in HDL level and resisted the rise (P=.05) in other lipid parameters and cardiac enzymes as after ISO induced myocardial injury. Pretreatment with extracts was significantly better (P=.05) than curative treatment. Gemmo extract was significantly better (P=.05) than native extract in preventive and curative treatment in normalizing serum levels of lipid parameters and cardiac enzymes in ISO injured rabbits.

Conclusion: The results provide evidence for the first time that gemmo extract of Glycyrrhiza glabra prevents myocardial injury induced by ISO in rabbits.