Human Umbilical Cord Blood–Derived CD34+Cells Can Be Used as a Prophylactic Agent for Experimental Heatstroke

Abstract

We attempted to assess the prophylactic effect of human umbilical cord blood–derived CD34+cells in experimental heatstroke. Anesthetized rats, 1 day before heat stress, were divided into 2 major groups and given CD34−cells (defined by 1 × 106human cord blood lymphocytes and monocytes that contained 95% CD34+cells). They were exposed to ambient temperature of 43°C for 70 min to induce heatstroke. When the CD34−cells–treated or untreated rats underwent heat stress, their survival time values were found to be 20 –24 min. Pretreatment with CD34+cells significantly increased survival time (123 –351 min). As compared with normothermic controls, all CD34−cells–treated heatstroke animals displayed hypotension, hepatic and renal failure, hypercoagulable state, activated inflammation, and cerebral ischemia and injury. However, these heatstroke reactions all were significantly suppressed by CD34+cells pretreatment. In addition, the levels of interlukin-10 in plasma and glial cell line–derived neurotrophic factors in brain were all significantly increased after CD34+cell administration during heatstroke. Our data indicate that human umbilical cord–derived CD34+cells can be used as a prophylactic agent for experimental heatstroke. Keywords:: heatstroke, CD34+cell, cytokine, multiorgan dysfunction, coagulation