Expression of receptors for melatonin (MT1), thyroid hormone (TR-α), deiodinase (Dio-2), glucose transporters (GLUT-1 &4) and its relation with splenic cell survival (Bcl-2) of golden hamster, Mesocricetus auratus

Abstract

Seasonal breeder utilises photoperiod as environmental clue to adjust their energetically demanding phenomenon such as reproduction and immunity by the mechanism of trade-off. The photoperiodic modulation of melatonin (MT-1)-thyroid hormone receptor (TR-α), deiodinase (Dio-2) activity and its interrelationship with glucose transporters (GLUT-1&4) in lymphoid organ of seasonal breeder is lacking that may explain possible role of photoperiod and its relationship with the cell survival factors (Bcl-2) in spleen of golden hamster, Mesocricetus auratus. We reported that photoperiod regulates the circulatory melatonin and thyroid hormone levels. Short-day-induced melatonin can act via MT1 and may enhance the expressions of GLUT-1&4 thereby the energy and cell survival factor (Bcl-2) in spleen. On the other hand, long-day-induced thyroid hormone is converted to bioactive from (T-4 to T3) by action of Dio-2 that acts through TR-α to maintain minimum level of energy for immune responses. In conclusion, present result explains the reason behind the basic molecular events involved in trade-offs mechanism in seasonal variation of immune responses.

Key words:

• Photoperiod
• golden hamster (Mesocricetus auratus)
• spleen
• thyroid hormone receptor (TR-α)/deiodinase (dio-2)
• melatonin receptor (MT1)
• glucose transporters (GLUT-1&4)

Acknowledgements

Author thanks CSIR, New Delhi, India for fellowship as JRF to Rakesh Verma (09/013(0517)/2013-EMR-I), CAS-UGC, BHU for departmental support and Alexander von Humboldt foundation Bonn, Germany for Instrument Subsidiary Award to Professor Chandana Haldar.