Heat Intolerance- A Lesson From Global Genomic Response in Lymphocytes

NCT00918359 | Unknown

• 1 other identifier: 782-2008-IDF-CTIL
• Study Type: observational
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Heat Intolerance; Genotypic Variations; Gene Expression; Genomic Markers for Predisposition of Heat Intolerance

Study Arms (2)

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 .

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• 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.

You may qualify if:

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

You may not qualify if:

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

Sponsors & Collaborators

• Medical Corps, Israel Defense Force: lead

Study Sites (1)

Heller Institute of Medical Research

Ramat Gan, 52621, Israel

RECRUITING

Biospecimen

Retention: SAMPLES WITH DNA

Whole blood

Central Study Contacts

Chen Makranz, Dr

CONTACT

03-7376584; chenma@sheba.health.gov.il

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: June 10, 2009
• First Posted: June 11, 2009
• Study Start: May 1, 2009
• Last Updated: June 29, 2011

Record last verified: 2011-06

Locations

IL (1)