No abstract

Globally, approximately 10%-25% of women smoke during pregnancy. Since nicotine is highly addictive, women may use nicotine-containing products like nicotine replacement therapies for smoking cessation, but the long-term consequences of early life exposure to nicotine remain poorly defined. Our laboratory has previously demonstrated that maternal nicotine exposed (MNE) rat offspring exhibit hypertriglyceridemia due to increased hepatic de novo lipogenesis. Hypertriglyceridemia may also be attributed to impaired white adipose tissue (WAT) lipid storage; however, the effects of MNE on WAT are not completely understood. We hypothesize that nicotine-induced alterations in adipose function (eg, lipid storage) underlie dyslipidemia in MNE adults. Female 6-month-old rats exposed to nicotine during gestation and lactation exhibited significantly decreased visceral adipocyte cell area by 40%, attributed, in part, to a 3-fold increase in adipose triglyceride lipase (ATGL) protein expression compared with vehicle. Given ATGL has antioxidant properties and in utero nicotine exposure promotes oxidative stress in various tissues, we next investigated if there was evidence of increased oxidative stress in MNE WAT. At both 3 weeks and 6 months, MNE offspring expressed 37%-48% higher protein levels of superoxide dismutase-1 and -2 in WAT. Since oxidative stress can induce inflammation, we examined the inflammatory profile of WAT and found increased expression of cytokines (interleukin-1β, tumor necrosis factor α, and interleukin-6) by 44%-61% at 6 months. Collectively, this suggests that the expression of WAT ATGL may be induced to counter MNE-induced oxidative stress and inflammation. However, higher levels of ATGL would further promote lipolysis in WAT, culminating in impaired lipid storage and long-term dyslipidemia.

Nineteen cycling ewes underwent transrectal ultrasonography of ovaries followed by ovariectomies during the growth phase of the first follicular wave of the interovulatory interval or the proestrus/estrus phase of the cycle. Quantitative ultrasonographic characteristics of the antrum and follicular wall in a total of forty-three ovine antral follicles were examined for correlations with the protein expression of three steroidogenic enzymes (cytochrome P450 17α-hydroxylase, CYP17; cytochrome P450 aromatase, CYP19; and 3β-hydroxysteroid dehydrogenase, 3β-HSD) determined by densitometric analysis of immunohistochemical slides, follicular dimensions, granulosa layer thickness and the percentage of apoptotic granulosa cells. Significant correlations were found between echotextural attributes of ovine antral follicles and the percentage of apoptotic granulosa cells, CYP17 expression (theca), CYP19 expression (granulosa) and 3β-HSD expression (theca cells). Computer-aided analyses of ultrasonographic images can be beneficial to the development of assisted reproductive technologies and diagnosis of hormonal imbalances without the need for ovarian biopsies or hormone assays.