Effect of Chronic and Acute Psychological Stress and Fluoxetine on Biomolecules of Heart

Background and Objective: Evidence-based knowledge of depression reveals the existence of co-morbidity with a wide range of diseases including cardiac dysfunction. Molecular indications between depression and the risk of heart failure are required for clinical correlation. The objective of the study was to evaluate the effect of both acute, chronic psychological stress and stress treatment (fluoxetine) on heart structure and functional biomolecules. Materials and Methods: Mild chronic and acute stress paradigm of 8 weeks was performed and compared with untreated (control group) and mild heat stress with isoproterenol (1 mg kg(-1) as per 8 week paradigm as negative control) in rats. Heart functionalities were checked by echocardiography and the level of monoamine oxidase enzyme activity was checked while heart failure molecular attribute was vested to Matrix Metalloproteinase (MMP). Contractility strength of left ventricular cardiac muscles strip along with caspase as an apoptotic attribute by western blotting was also carried out to strengthen the conclusion. Results: Results clearly showed the significant effects of psychological stress on heart functionalities (ejection fraction (%), heart rate, absolute heart mass, systolic and diastolic left ventricular pressure), MMP level, cardiac contractility and caspase expression (p<0.05 for all). The effect of fluoxetine treatment attenuated the contractility in terms of passive strength reaching to level of the control group only while there was a large difference between acute stress only and acute stress with fluoxetine treatment (p<0.05) but not reaching to level of the control group (p<0.05 for both). Conclusion: The effect of mental stress on organ functionality and structure is wide and conspicuous but was not perceptibly protected by the psychological treatment given in this study.