Expression of aryl hydrocarbon receptor (AHR) and aryl hydrocarbon receptor nuclear translocator (ARNT) mRNA expression in human spermatozoa.
BACKGROUND
The objective of this study was to determine if human spermatozoa express AHR (dioxin receptor) and ARNT and if mRNA levels for these transcription factors correlate with sperm concentration, motility or morphology.


METHODS
This was a case-controlled cohort study in which AHR and ARNT mRNA levels in subjects with normal and abnormal semen analysis were compared. Semen analysis was performed by CASA. AHR/ARNT mRNA levels were determined by multiplex RT-PCR using Glyceryl aldehyde 3-phospho dehydrogenase (G3PDH) as an internal control.


RESULTS
Human sperm expresses abundant amounts of AHR and ARNT mRNA. There were no differences in AHR and ARNT mRNA levels in subjects with normal and abnormal semen analysis. AHR and ARNT levels did not correlate with sperm concentration, morphology or motility. There was a trend (p=0.07) for lower AHR mRNA expression in sperm of men with severe oligospermia. There was a significant negative correlation (r=-0.42, p<0.05) between sperm AHR and ARNT mRNA.


CONCLUSIONS
The presence of AHR in sperm provides a mechanism by which environmental dioxins, polycyclic aromatic hydrocarbons and polyhalogenated biphenyls could directly influence sperm function.
Khorram
Omid
O
Department of Obstetrics and Gynecology, University of Wisconsin, and Wisconsin Regional Primate Research Center, Madison, WI, USA. okhorram@obgyn.humc.edu
Garthwaite
Mark
M
Jones
Jeffrey
J
Golos
Thaddeus
T
D056930:ARNTL Transcription Factors; D051792:Basic Helix-Loop-Helix Proteins; D016022:Case-Control Studies; D002465:Cell Movement; D015331:Cohort Studies; D017931:DNA Primers / Q000737:chemistry; D004147:Dioxins / Q000378:metabolism; D006801:Humans; D006838:Hydrocarbons / Q000737:chemistry; D007248:Infertility, Male; D008297:Male; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism*; D018336:Receptors, Aryl Hydrocarbon / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012661:Semen / Q000378:metabolism; D013053:Spectrophotometry; D013094:Spermatozoa / Q000378:metabolism; D014157:Transcription Factors / Q000096:biosynthesis*; D014158:Transcription, Genetic
D056930:ARNTL Transcription Factors; D051792:Basic Helix-Loop-Helix Proteins; D017931:DNA Primers; D004147:Dioxins; D006838:Hydrocarbons; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D014157:Transcription Factors; C538960:BMAL1 protein, human