PROTECTIVE ROLE OF LACTOBACILLUS ACIDOPHILUS IN HYPOTHALAMUS- PITUITARY- ADRENAL (HPA) AXIS PERFORMANCE IN HEAT STRESSED RATS

Abstract

The present study was undertaken to study the protective role of Lactobacillus acidophilus against deleterious changes of Hypothalamus pituitary adrenal (HPA) axis in heat stress, adult female (n=24) Albino Wister rats were divided into four equal groups; 1st control (C) group maintained at (22-25˚C), 2nd (HS) group exposed to high ambient temperature (35 - 40˚C) for 6 hours daily, 3rd (HS-LBA). group administered L acidophilus (5 × 108 CFU) and exposed to heat stress, 4th (LBA) group administered L. acidophilus (5 × 108 CFU). Results revealed that heat stress disorders of, hyperthermia, anxiety and decreased relative growth rate RGR were ameliorated by administration of Lactobacillus acidophilus. Further-more, the typical biomar-kers for hypothalamus–pituitary–adrenal axis hyper sensitivity and sympathetic system activity (cortisole, adrenocorticotropic, adrenalin, & noradrenalin) were elevated in HS group, and return to semi normal level in HS-LBA and LBA groups. Analysis of brain tissue and duo-denum sections showed marked inflammatory and irregularity of histopathological changes. These changes disappeared in groups with L. acidophilus. In conclusion, the present study demonstrated for the first time that L. acidophilus improves deleterious deviation in HPA axis hypersensitivity and sympathetic system activity caused by heat stress. These changes confirmed the success of heat stress resistance through a positive role of L. acidophilus in gut-brain-axis. This study demonstrated for the first-time efficacy of L. acidophilus in reducing heat stress effects mediated by gut-brain axis.