title: Two years of combined high-intensity physical training and heat acclimatization affect lymphocyte and serum HSP70 in purebred military working dogs.
abstract: Military working dogs in hot countries undergo exercise training at high ambient temperatures for at least 9 mo annually. Physiological adaptations to these harsh conditions have been extensively studied; however, studies focusing on the underlying molecular adaptations are limited. In the current study, military working dogs were chosen as a model to examine the effects of superimposing endurance exercise on seasonal acclimatization to environmental heat stress. The lymphocyte HSP70 profile and extracellular HSP70 were studied in tandem with physiological performance in the dogs from their recruitment for the following 2 yr. Aerobic power and heat shock proteins were measured at the end of each summer, with physical performance tests (PPTs) in an acclimatized room (22°C). The study shows that together with a profound enhancement of aerobic power and physical performance, hsp72 mRNA induction immediately post-PPT and 45 min later, progressively increased throughout the study period (relative change in median lymphocyte hsp72 mRNA first PPT, 4.22 and 12.82; second PPT, 17.19 and 109.05, respectively), whereas induction of HSP72 protein was stable. These responses suggest that cellular/molecular adaptive tools for maintaining HSP72 homeostasis exist. There was also a significant rise in basal and peak median optical density extracellular HSP at the end of each exercise test (first PPT, 0.13 and 0.15; second PPT, 1.04 and 1.52, respectively). The relationship between these enhancements and improved aerobic power capacity is not yet fully understood.
authors.affiliation: The Hebrew University Veterinary Teaching Hospital, Koret School of Veterinary Medicine, The Hebrew University of Jerusalem; bruchim@agri.huji.ac.il.
authors.forename: Yaron
authors.initials: Y
authors.lastname: Bruchim
authors.affiliation: The Hebrew University Veterinary Teaching Hospital, Koret School of Veterinary Medicine, The Hebrew University of Jerusalem;
authors.forename: Itamar
authors.initials: I
authors.lastname: Aroch
authors.affiliation: The Hebrew University Veterinary Teaching Hospital, Koret School of Veterinary Medicine, The Hebrew University of Jerusalem;
authors.forename: Ady
authors.initials: A
authors.lastname: Eliav
authors.affiliation: Laboratory of Environmental Physiology, Hadassah Medical Center, The Hebrew University of Jerusalem;
authors.forename: Atallah
authors.initials: A
authors.lastname: Abbas
authors.affiliation: Israel Defense Force Military Working Dog Unit.
authors.forename: Ilan
authors.initials: I
authors.lastname: Frank
authors.affiliation: The Hebrew University Veterinary Teaching Hospital, Koret School of Veterinary Medicine, The Hebrew University of Jerusalem;
authors.forename: Efrat
authors.initials: E
authors.lastname: Kelmer
authors.affiliation: The Hebrew University Veterinary Teaching Hospital, Koret School of Veterinary Medicine, The Hebrew University of Jerusalem;
authors.forename: Carolina
authors.initials: C
authors.lastname: Codner
authors.affiliation: The Hebrew University Veterinary Teaching Hospital, Koret School of Veterinary Medicine, The Hebrew University of Jerusalem;
authors.forename: Gilad
authors.initials: G
authors.lastname: Segev
authors.affiliation: Heller Institute of Medical Research, Chaim Sheba Medical Center, Tel Hashomer, and Tel-Aviv University Medical School, Israel; and.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Epstein
authors.affiliation: Laboratory of Environmental Physiology, Hadassah Medical Center, The Hebrew University of Jerusalem;
authors.forename: Michal
authors.initials: M
authors.lastname: Horowitz
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D004285:Dogs; D017079:Exercise Tolerance / Q000502:physiology*; D018840:HSP70 Heat-Shock Proteins / Q000097:blood* / Q000378:metabolism*; D006358:Hot Temperature; D008214:Lymphocytes / Q000378:metabolism*; D008889:Military Personnel; D010805:Physical Conditioning, Animal / Q000502:physiology*; D013312:Stress, Physiological / Q000502:physiology
chemical_list: D018840:HSP70 Heat-Shock Proteins
keywords: Belgian Malinois; HSP70; canine; eHSP70; endurance exercise; heat acclimatization; heat stress