Heat Intolerance- A Lesson From Global Genomic Response in Lymphocytes

Following Study: Heat Intolerance- A Lesson From Global Genomic Response in Lymphocytes

Heat Intolerance (HI) is a life threatening deficiency that can lead to heat exhaustion, heat stroke (and possibly death) in a large number of military and civilian occupational groups. We have demonstrated malfunction of transcriptional pathways in the heat stressed HI phenotype and an altered gene expression profile compared to Heat Tolerant (HT) individuals. Such differences are evident even under normothermic basal/comfort conditions. Heat and exercise challenges during the heat tolerance test (HTT) further emphasize the differences between the groups, particularly during recovery at comfort temperatures. Our results indicate that it may be possible to identify markers of heat intolerance. To achieve this goal, we plan to design a cellular (lymphocyte) HTT experimental model and detect gene expression profiles using customized DNA microarrays and bioinformatic tools (the genes selected will be based on our previous DNA microarray studies). Lymphocyte samples collected from HT and HI individuals under resting/comfort conditions will be examined. Treatments and analyses are designed to reveal HI-associated gene-expression profiles (constitutive or inducible), and thereby find lymphocyte markers to identify individuals predisposed to heat injury. The identification of such subjects could prevent unnecessary loss of life. Notably, the rapidly changing climate in our era increases the number of occupation/age groups in which manifestations of HI will appear.

Study Overview

• Status: Unknown
• Conditions: Heat Intolerance; Gene Expression; Genotypic Variations; Genomic Markers for Predisposition of Heat Intolerance

• Study Type: Observational
• Enrollment (Anticipated): 50

Contacts and Locations

• Study Contact: Name: Chen Makranz, Dr; Phone Number: 03-7376584; Email: chenma@sheba.health.gov.il

Study Locations

• Israel
  • Ramat Gan, Israel, 52621
    • Recruiting
    • Heller Institute of Medical Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

• Sampling Method: Probability Sample

Study Population

Blood samples of HT and HI subjects will be collected from volunteers who experienced heat exhaustion or heat stroke in their past and participating in heat tolerance test (HTT). The test, using conservative criteria discriminates between HI and HT groups. The distinction between HI and HT groups occurs only following analyses of the HTT.

Description

Inclusion Criteria:

• Experienced heat exhaustion or heat stroke in their past
• Participating in heat tolerance tests (HTT)

Exclusion Criteria:

• Unambiguous result of the HTT
• HTT stop by the subject decision

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
HI; Subjects who experienced heat exhaustion or heat stroke in their past and will be identified by heat tolerance test (HTT) as Heat Intolerance .
HT; Subjects who experienced heat exhaustion or heat stroke in their past and will be identified by heat tolerance test (HTT) as Heat Tolerance .

Collaborators and Investigators

• Sponsor: Medical Corps, Israel Defense Force

Study record dates

Study Major Dates

• Study Start: May 1, 2009

Study Registration Dates

• First Submitted: June 10, 2009
• First Submitted That Met QC Criteria: June 10, 2009
• First Posted (Estimate): June 11, 2009

Study Record Updates

• Last Update Posted (Estimate): June 29, 2011
• Last Update Submitted That Met QC Criteria: June 28, 2011
• Last Verified: June 1, 2011

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Disease Susceptibility
• Other Study ID Numbers: 782-2008-IDF-CTIL