Short day length enhances physiological resilience of the immune system against 2-deoxy-d-glucose-induced metabolic stress in a tropical seasonal breeder Funambulus pennanti.
Studies demonstrate the importance of metabolic resources in the regulation of reproduction and immune functions in seasonal breeders. In this regard, the restricted energy availability can be considered as an environmental variable that may act as a seasonal stressor and can lead to compromised immune functions. The present study explored the effect of photoperiodic variation in the regulation of immune function under metabolic stress condition. The T-cell-dependent immune response in a tropical seasonal breeder Funambulus pennanti was studied following the inhibition of cellular glucose utilization with 2-deoxy-d-glucose (2-DG). 2-DG treatment resulted in the suppression of general (e.g., proliferative response of lymphocytes) and antigen-specific [anti-keyhole limpet hemocyanin IgG titer and delayed-type hypersensitivity response] T-cell responses with an activation of the hypothalamic-pituitary-adrenal axis, which was evident from the increased levels of plasma corticosterone. 2-DG administration increased the production of inflammatory cytokines [interleukin (IL)-1β and tumor necrosis factor (TNF)-α] and decreased the autocrine T-cell growth factor IL-2. The immunocompromising effect of 2-DG administration was retarded in animals exposed to short photoperiods compared with the control and long photoperiod-exposed groups. This finding suggested that short photoperiodic conditions enhanced the resilience of the immune system, possibly by diverting metabolic resources from the reproductive organs toward the immune system. In addition, melatonin may have facilitated the energy "trade-off" between reproductive and immune mechanisms, thereby providing an advantage to the seasonal breeders for their survival during stressful environmental conditions.
['Gupta|Sameer|S|', 'Haldar|Chandana|C|']
D000818:Animals D001786:Blood Glucose D001947:Breeding D003345:Corticosterone D003847:Deoxyglucose D004734:Energy Metabolism D007030:Hypothalamo-Hypophyseal System D007121:Immunocompetence D008550:Melatonin D017440:Photoperiod D010913:Pituitary-Adrenal System D012098:Reproduction D012589:Sciuridae D012621:Seasons D013312:Stress, Physiological D014329:Tropical Climate
Stress Photoperiod 2-Deoxy-d-glucose Melatonin Immune status