Sex-dependent mechanisms involved in renal tolerance to ischemia-reperfusion: Role of inflammation and histone H3 citrullination

Transpl Immunol. 2020 Dec:63:101331. doi: 10.1016/j.trim.2020.101331. Epub 2020 Sep 3.

Abstract

Ischemia-reperfusion (I/R) injury, an inevitable result of kidney transplantation, triggers early inflammatory events that affect graft viability. Evidence from human transplantation and preclinical models of I/R suggests that a female hormonal environment positively influences the ability to recover from ischemic injury. However, the mechanisms behind these effects remain mostly unexplored. Here, we studied the influence of sex on pro-inflammatory mediators involved in the pathophysiology of acute I/R injury in male, female, and female ovariectomized (OVX) Wistar rats that underwent unilateral renal ischemia for 45 min, followed by 24 h of reperfusion. We found improved renal function, reduced cytokine expression, and decreased infiltration of myeloperoxidase-positive cells in females after I/R, when compared to their male and female OVX counterparts. Remarkably, citrullination of histone H3 was exacerbated in serum and renal tubules of females after I/R. In contrast, we observed lower levels of citrullinated histone H3 in male and female OVX rats in response to I/R, mostly in neutrophil extracellular traps. Our results demonstrate that female sex promotes renal I/R tolerance by attenuating pro-inflammatory mediators involved in I/R-induced damage.

Keywords: Histone citrullination; Inflammation; Ischemia-reperfusion; Ovarian hormones; Sexual dimorphism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Citrullination
  • Disease Resistance
  • Extracellular Traps / metabolism
  • Female
  • Gonadal Steroid Hormones / metabolism*
  • Histones / metabolism*
  • Humans
  • Inflammation / immunology*
  • Kidney / metabolism*
  • Kidney / pathology
  • Kidney Transplantation*
  • Male
  • Ovariectomy
  • Rats, Wistar
  • Reperfusion Injury / epidemiology
  • Reperfusion Injury / immunology*
  • Sex Characteristics
  • Sex Factors

Substances

  • Gonadal Steroid Hormones
  • Histones