Melatonin and thermal stress regulate differential expression of heat shock proteins and melatonin receptors in spleen of mice

Abstract

Cellular defence by expression of heat shock proteins (Hsps) against stress stimulation is the
most universal phenomenon in stress physiology. Melatonin is well known as an anti-stress
molecule possessing hypothermic effects. It protects cells and tissues in stressed conditions.
Individually, Hsp70 and melatonin shows its functional ability in stressed organisms as well
as in immune functions. The aim of the present study was to determine the interaction of
melatonin receptors (MT1/MT2) in exogenous melatonin modulated expression of heat shock
proteins (Hsp70/Hsc70) in spleen of thermally stressed male mice. Results of the study
showed thermal stress significantly increased the Hsp70/Hsc70 and melatonin receptor MT2
expression in spleen of mice. The administration of melatonin significantly increased Hsp70
expression, but decreased Hsc70 expression. Both MT1/MT2 receptor expressions increased
after melatonin treatment, whereas thermal stress to melatonin treated mice showed decrease
in MT1/MT2 receptor expression than the only melatonin treated mice. MT2 receptor is
responding in all experimental conditions corresponding to changes in Hsp70 protein
expression. Therefore, the present study might suggest that MT2 receptor is interacting in
coordination of melatonin mediated heat shock proteins expression in mice spleen after
thermally stressed conditions.