Heat stress and sudden infant death syndrome--stress gene expression after exposure to moderate heat stress

Forensic Sci Int. 2013 Oct 10;232(1-3):16-24. doi: 10.1016/j.forsciint.2013.06.003. Epub 2013 Jul 27.

Abstract

The aim of the present study was to investigate stress gene expression in cultured primary fibroblasts established from Achilles tendons collected during autopsies from sudden infant death syndrome (SIDS) cases, and age-matched controls (infants dying in a traumatic event). Expression of 4 stress responsive genes, HSPA1B, HSPD1, HMOX1, and SOD2, was studied by quantitative reverse transcriptase PCR analysis of RNA purified from cells cultured under standard or various thermal stress conditions. The expression of all 4 genes was highly influenced by thermal stress in both SIDS and control cells. High interpersonal variance found in the SIDS group indicated that they represented a more heterogeneous group than controls. The SIDS group responded to thermal stress with a higher expression of the HSPA1B and HSPD1 genes compared to the control group, whereas no significant difference was observed in the expression of SOD2 and HMOX1 between the two groups. The differences were related to the heat shock treatment as none of the genes were expressed significantly different in SIDS at base levels at 37 °C. SOD2 and HMOX1 were up regulated in both groups, for SOD2 though the expression was lower in SIDS at all time points measured, and may be less related to heat stress. Being found dead in the prone position (a known risk factor for SIDS) was related to a lower HSPA1B up-regulation in SIDS compared to SIDS found on their side or back. The study demonstrates the potential usefulness of gene expression studies using cultured fibroblasts established from deceased individuals as a tool for molecular and pathological investigations in forensic and biomedical sciences.

Keywords: Fibroblast culture; Heat stress; Infant death; QRT-PCR; SIDS.

MeSH terms

  • Achilles Tendon / cytology
  • Case-Control Studies
  • Cells, Cultured
  • Chaperonin 60 / genetics*
  • Fibroblasts / metabolism
  • Fibroblasts / pathology
  • Forensic Genetics
  • Forensic Pathology
  • HSP70 Heat-Shock Proteins / genetics*
  • Heat Stress Disorders / genetics*
  • Heme Oxygenase-1 / genetics*
  • Hot Temperature
  • Humans
  • Infant
  • Infant, Newborn
  • Mitochondrial Proteins / genetics*
  • Prone Position
  • RNA, Messenger / metabolism
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sudden Infant Death / genetics*
  • Superoxide Dismutase / genetics*
  • Time Factors
  • Up-Regulation

Substances

  • Chaperonin 60
  • HSP70 Heat-Shock Proteins
  • HSPA1B protein, human
  • HSPD1 protein, human
  • Mitochondrial Proteins
  • RNA, Messenger
  • HMOX1 protein, human
  • Heme Oxygenase-1
  • Superoxide Dismutase
  • superoxide dismutase 2