β-Alanine Supplementation Attenuates the Neurophysiological Response in Animals Exposed to an Acute Heat Stress

Abstract

The effect of 30 days of β-alanine supplementation on neurophysiological responses of animals exposed to an acute heat stress (HS) was examined. Animals were randomized to one of three groups; exposed to HS (120 min at 40–41 °C) and fed a normal diet (EXP; n = 12); EXP and supplemented with β-alanine (EXP + BA; n = 10); or not exposed (CTL; n = 10). Hippocampal (CA1, CA3 and DG) and hypothalamic (PVN) immunoreactive (ir) cell numbers of COX2, IBA-1, BDNF, NPY and HSP70 were analyzed. Three animals in EXP and one in EXP–BA did not survive the HS, however no significant difference (p = 0.146) was noted in survival rate in EXP + BA. The % change in rectal temperature was significantly lower (p = 0.04) in EXP + BA than EXP. Elevations (p’s < 0.05) in COX-2, IBA-1 and HSP70 ir-cell numbers were noted in animals exposed to HS in all subregions. COX-2 ir-cell numbers were attenuated for EXP + BA in CA1 (p = 0.02) and PVN (p = 0.015) compared to EXP. No difference in COX-2 ir-cell numbers was noted between CTL and EXP + BA at CA1. BDNF-ir cell numbers in CA1, DG and PVN were reduced (p’s < 0.05) during HS compared to CTL. No difference in BDNF-ir cell numbers was noted between EXP + BA and CTL in CA3 and PVN. NPY-ir density was reduced in exposed animals in all subregions, but NPY-ir density for EXP-BA was greater than EXP in CA3 (p < 0.001) and PVN (p = 0.04). β-Alanine supplementation attenuated the thermoregulatory and inflammatory responses and maintained neurotrophin and neuropeptide levels during acute HS. Further research is necessary to determine whether β-alanine supplementation can increase survival rate during a heat stress.

Keywords:

• brain
• hippocampus
• hypothalamus
• inflammation
• thermoregulation

Additional information

Funding

The authors would like to thank Natural Alternatives International (Carlsbad, CA, USA) for providing support for this study. The funding source was not involved in data collection, interpretation, or analysis of data or in writing the report.

Notes on contributors

Tal Belity

Tal Belity, at the time of the study was a master’s student in the Department of Clinical Biochemistry and Pharmacology within the Faculty of Health Sciences at Ben-Gurion University of the Negev in Israel. She is now in performing her internship for licensure as a registered dietician.

Jay R. Hoffman

Jay R. Hoffman, is a full professor in the Department of Physical Therapy within the Faculty of Health Sciences at Ariel University in Israel.

Michal Horowitz

Michal Horowitz, is a full professor in the Department of Laboratory of Environmental Physiology within the Faculty of Dental Medicine at The Hebrew University of Jerusalem in Israel.

Yoram Epstein

Yoram Epstein, works at the Heller Institute of Medical Research at Sheba Medical Center and a Professor within the Sackler Faculty of Medicine at Tel Aviv University in Israel.

Yaron Bruchim

Yaron Bruchim, is at The Hebrew University Veterinary Teaching Hospital and the Koret School of Veterinary Medicine at The Hebrew University of Jerusalem in Israel. He also is works within a veterinarian practice

Hagit Cohen

Hagit Cohen, works at the Beer-Sheva Mental Health Center within the Ministry of Health, Anxiety and Stress Research Unit and is also a full professor in the Department of Clinical Biochemistry and Pharmacology within the Faculty of Health Sciences at Ben-Gurion University of the Negev in Israel.