Hypothermia as a cytoprotective strategy in ischemic tissue injury

Abstract

Hypothermia is a well established cytoprotectant, with remarkable and consistent effects demonstrated across multiple laboratories. At the clinical level, it has recently been shown to improve neurological outcome following cardiac arrest and neonatal hypoxia ischemia. It is increasingly being embraced by the medical community, and could be considered an effective neuroprotectant. Conditions such as brain injury, hepatic encephalopathy and cardiopulmonary bypass seem to benefit from this intervention. It's role in direct myocardial protection is also being explored. A review of the literature has demonstrated that in order to appreciate the maximum benefits of hypothermia, cooling needs to begin soon after the insult, and maintained for relatively long period periods of time. In the case of ischemic stroke, cooling should ideally be applied in conjunction with the reestablishment of cerebral perfusion. Translating this to the clinical arena can be challenging, given the technical challenges of rapidly and stably cooling patients. This review will discuss the application of hypothermia especially as it pertains to its effects neurological outcome, cooling methods, and important parameters in optimizing hypothermic protection.

The Science of Stroke: Mechanisms in Search of Treatments

“…Inflammatory markers decrease, as well as microglial activation, leucocyte infiltration, MMP activation and BBB disruption. In addition, hypothermia suppresses apoptotic cell death, decreases mitochondrial release of cytochrome C and apoptosis inducing factor (see for review (Tang and Yenari, 2009)). Cell survival pathways are upregulated and appear to contribute to the multiplicity of neuroprotective mechanisms.…”

Downregulation of Metabolic Activity Increases Cell Survival Under Hypoxic Conditions: Potential Applications for Tissue Engineering

“…[27][28][29][30][31] For example, induced hypothermia has been routinely used in surgery since the early 1950s. 30 It is a well-established means of cytoprotection in which, lowering temperature slows metabolism and renders cells in a suspended state to maintain cell survival. However, only a few clinical studies have convincingly demonstrated a role in humans.…”

Effect of mild hypothermia on breast cancer cells adhesion and migration

“…Although many prevention methods such as chemoprevention, risk-reduction surgery, molecular genetics, epidemiology, and imaging have been used to reduce the incidence of cancer, few have paid attention to mild hypothermia (32-35ºC) as a strategy to prevent tumor cell adhesion and extravasation although mild hypothermia (32-35ºC) has been studied to improve outcome from cardiac arrest, brain trauma, stroke, hypoxic encephalopathy of neonates, spinal cord injury, open cardiac surgery, and other ischemic tissue injury for a long time (18). One of the important mechanisms is that mild hypothermia inhibits the inflammation response which contributes significantly to secondary injury after ischemia (19,20).…”