Paternal alcohol exposure affected offspring mesenteric artery via ROS-Cacna1c and DNA hypomethylation.

Background: Paternal preconception alcohol exposure affects fetal development; however, it is largely unknown about the influences on offspring vasculature and mechanisms.

Methods: Offspring born form paternal rats treated with alcohol or water before pregnant was raised until 3 months of age. Vessel tone of mesenteric arteries was detected using myograph system; whole-cell calcium channel current in smooth muscle cells was tested using patch-clamp; molecule expressions were detected with real-time PCR, western blotting, and Dihydroethidium (DHE); DNA methylations were determined using targeted bisulfate sequencing assay. Following 5-aza-2'-deoxycytidine incubation, vessel tone in offspring mesenteric artery and Cacna1c expression in A7r5 was tested.

Results: When comparing with the control, stress-strain curve was left-shifted in alcohol. There was lower incremental distensibility and endothelium-dependent dilation associated with endothelial nitric oxide synthase. Agonists-induced constrictions were greater in alcohol offspring than that in control, associated with higher expression of AT1R, Cacna1c, and reactive oxygen species (ROS). Baseline and Ang II-stimulated calcium channel currents were higher in alcohol group. Tempol and apocynin could restore Ang II-increased constriction and calcium channel current in alcohol offspring. When comparing with the control, there was lower DNA methylation of Cacna1c promotor in alcohol offspring mesenteric artery and in paternal sperm. 5-aza-2'-deoxycytidine increased contraction in control offspring mesenteric artery and Cacna1c expression in A7r5.

Conclusion: Paternal preconception alcohol exposure-affected offspring mesenteric artery was via ROS-Cacna1c. Abnormal offspring vascular functions might be inherited via DNA hypomethylation of Cacna1c promotor from paternal sperm exposed to alcohol. These data gained provided important clues for cardiovascular disorders at germ cell origin.