An assessment of ischemia-reperfusion injury in rats exposed to chronic psychological stress

Date
2019-12
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Cardiovascular disease remains the leading cause of death worldwide. Apart from known risk factors such as poor dietary intake, physical inactivity and smoking, chronic psychological stress is emerging as an important modifiable risk factor in the development of cardiovascular disease. The body relies on two physiological mechanisms to counter acute stressors and to achieve and/or maintain homeostasis, i.e. the hypothalamic-pituitary-adrenal axis and the autonomic nervous system. However, chronic activation of these systems can lead to the disruption of cellular and systemic processes that could potentially result in the development of neurological or psychosomatic diseases. Both chronic stress and ischemia-reperfusion injury are associated with a robust inflammatory response and the induction of oxidative stress. Does chronic psychological stress render the heart more susceptible to ischemia and reperfusion damage, and what are the role(s) of oxidative stress and inflammation in stress-related cardiac dysfunction? These questions will form the basis of this review. Following a comprehensive review, we established that chronic stress does render the heart more susceptible to damage following ischemia-reperfusion. After reviewing the mechanisms involved in both ischemia-reperfusion and chronic stress, we hypothesized that chronic stress induced inflammation and oxidative stress are major contributors in aggravated ischemia-reperfusion injury.
AFRIKAANSE OPSOMMING: Kardiovaskulêre siektes is jaarliks die grootste oorsaak van dood wêreldwyd. Behalwe die bekende risikofaktore soos swak dieetinname, fisiese onaktiwiteit en rook, verskyn kroniese psigologiese stres as 'n belangrike veranderlike risikofaktor in die ontwikkeling van miokardiale infarksie. Die liggaam maak staat op twee fisiologiese meganismes om akute stressors teen te werk en homeostase te bewerkstellig of te handhaaf, naamlik die hipotalamus-pituïtêre-byniere-as en die outonome senuweestelsel. Alhoewel dit 'n gekoördineerde fisiologiese reaksie is wat homeostase handhaaf, kan kroniese aktivering van hierdie stelsel lei tot die ontwrigting van sellulêre en sistemiese prosesse wat moontlik kan lei tot die ontwikkeling van neurologiese of psigosomatiese siektes. Beide kroniese sielkundige stres en iskemie-reperfusiebesering word geassosieer met 'n sterk inflammatoriese reaksie en die induksie van oksidatiewe stres. Maak kroniese psigologiese stres die hart meer vatbaar vir skade na iskemie en reperfusie, en wat is die rol van oksidatiewe stres en inflammasie in stresverwante disfunksie van die hart? Hierdie vraag vorm die basis van hierdie oorsig. Na 'n omvattende oorsig het ons vasgestel dat kroniese stres die hart meer vatbaar maak vir skade na die induksie van iskemieherperfusie. Na die hersiening van die meganismes wat betrokke is by iskemie-reperfusie en kroniese stres, het ons die hipotese vasgestel dat kroniese stres-geïnduseerde inflammasie en oksidatiewe stres belangrike bydraers is tot die verergering iskemie-reperfusie skade.
Description
Thesis (MSc)--Stellenbosch University, 2019.
Keywords
Stress (Psychology), Cardiovascular system -- Diseases, Rats -- Effect of stress on, Ischaemia-Reperfusion injury, Hypothalamic-pituitary-adrenal axis -- Effect of stress on, Wound healing -- Animal models, UCTD
Citation