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Multiple metals predict prolactin and thyrotropin (TSH) levels in men
John D Meeker1, Mary G Rossano, Bridget Protas
1Department of Environmental Health Sciences, University of Michigan School of Public Health, 6635 SPH Tower, 109 S. Observatory St., Ann Arbor, MI 48109, USA. meekerj@umich.edu
Environmental Research
|July 15, 2009
Summary
This study found that blood metal levels impact hormone regulation in men. Higher levels of metals like arsenic and lead were linked to altered prolactin (PRL) and thyrotropin (TSH) levels, affecting neuroendocrine and thyroid function.
Area of Science:
- Environmental Health
- Endocrinology
- Toxicology
Background:
- Metal exposure can disrupt neuroendocrine and thyroid signaling pathways.
- These disruptions may lead to adverse effects on development, behavior, metabolism, and reproduction.
- Understanding metal-environment interactions is crucial for male reproductive health.
Purpose of the Study:
- To investigate the association between blood metal concentrations and serum prolactin (PRL) and thyrotropin (TSH) levels in men.
- To identify specific metals that correlate with altered dopaminergic and thyroid markers.
- To contribute to the understanding of environmental influences on male endocrine and thyroid function.
Main Methods:
- Analysis of blood samples from 219 men for 11 metal concentrations.
- Measurement of serum prolactin (PRL) and thyrotropin (TSH) levels.
- Application of multiple linear regression models, adjusting for age, BMI, and smoking status.
Main Results:
- Serum PRL was inversely associated with arsenic, cadmium, copper, lead, manganese, molybdenum, and zinc.
- Serum PRL showed a positive association with chromium.
- Lead and copper were linked to a non-monotonic decrease in TSH, while arsenic showed a dose-dependent increase in TSH.
Conclusions:
- Blood metal concentrations are associated with altered prolactin and thyrotropin levels in men.
- Specific metals like arsenic, cadmium, lead, and copper may play a significant role in neuroendocrine and thyroid function.
- Further research is warranted to elucidate the mechanisms and health implications of metal-induced endocrine disruption.
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