1 Tahrcountry Musings: Study of hibernation in black bears brings unexpected bonanza

Tuesday, March 20, 2012

Study of hibernation in black bears brings unexpected bonanza

Scientists studying hibernation by black bears (Ursus americanus Pallas, 1780) were surprised to observe that hibernating American black bears exhibit profound abilities in mounting inflammatory responses to infection and/or foreign bodies. The bears resolve injuries during hibernation while maintaining mildly hypothermic states (30–35 °C) and without eating, drinking, urinating or defecating.  Usually even mildly hypothermic body or limb temperatures can retard healing processes in mammals. 

The researchers induced small, full-thickness cutaneous wounds (biopsies or incisions) during early denning, and re-biopsied sites 2–3 months later (near the end of denning). Routine histological methods were used to characterize these skin samples. All biopsied sites with respect to secondary intention (open circular biopsies) and primary intention (sutured sites) healed, with evidence of initial eschar (scab) formation, completeness of healed epidermis and dermal layers, dyskeratosis (inclusion cysts), and abilities to produce hair follicles.

The researchers say further research in to the underlying mechanisms of wound healing during hibernation could have applications in human medicine. They add that unique approaches may be found to improve healing for malnourished, hypothermic, diabetic and elderly patients or to reduce scarring associated with burns and traumatic injuries.

Journal reference
Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation
Paul A. IAIZZo,Timothy G. LASKE,Henry J. HARLOw,Carolyn B. McCLAy and David L. GARSHELIS
Integrative Zoology,Volume 7, Issue 1, pages 48–60, March 2012

No comments: