Estrogens, Conjugated Synthetic B(Teva Pharmaceutical Industries Ltd.)

The widespread use of synthetic phenolic antioxidants (SPAs) has led to their ubiquity and may contribute to multiple adverse health outcomes by affecting hormone level disruption. This study aimed to assess the exposure levels of SPAs in the plasma of the normoglycemic rural Chinese population, investigate the association of single and mixed pollutant exposures with sex hormones, and analyze the moderating role of body mass index (BMI) in these relationships. A cross-sectional study including 763 individuals with normal blood glucose from the Henan Rural cohort was conducted. General linear models, restricted cubic spline models, quantile-based g computation (qgcomp), and Bayesian kernel machine regression (BKMR) were utilized to evaluate single, nonlinear, and mixed relationships between SPAs exposure and sex hormones. The combined and additive interactions of SPAs and BMI on sex hormones were further examined. SPAs were widely detected in the plasma samples of the normoglycemic rural Chinese population, and SPAs were significantly linked to altered progestogen and androgen levels in single exposure and varied by gender and menopausal status, and some of these associations were non-linear. Being overweight/obesity strengthened the effect of SPAs on androgens and estrogens. Mixture effect analyses suggested a positive joint mixture effect of SPAs with progesterone in men, and a negative joint mixture effect of SPAs with 17-hydroxyprogesterone, testosterone, and androstenedione in both men and postmenopausal women. The relative contribution of AO44B25, AO425, BHA, BHT-OH, and AO2246 to the overall mixing effect was higher in both mixture analyses. This study is the first to profile SPAs in plasma samples from the Chinese rural population and to identify significant associations between SPAs exposure and altered progestogen and androgen levels in men and postmenopausal women, providing epidemiological evidence for the endocrine-disrupting effects of SPAs and research basis for exploring the etiology of multiple diseases caused by environmental pollution.

Based on an exhaustive review, a theory was proposed with an immunoendocrine perspective on the reactivation of dormant Toxocara canis larvae in pregnant bitches and their transmission to fetuses through the placenta, or milk and colostrum to puppies. A historical review was carried out on the reactivation of dormant larvae of T. canis in pregnant bitches which suggested that larval reactivation of T. canis is not solely the effect of a single hormone (prolactin) but is the result of a series of events triggered by progesterone, prolactin, and estrogens. In the first third of gestation, progesterone is capable of directly stimulating the reactivation of larvae through hormonal receptors, indirectly downregulating the granulomatous proinflammatory response around dormant T. canis larvae, and directing the response to a Th2 profile with increased levels of antibodies and blood eosinophils. After a time, when progesterone levels decrease, prolactin and estrogen maintain larval stimulation through hormonal receptors and downregulation of Th1 and the granulomatous proinflammatory response. Collectively, these hormones play major roles in the reactivation of T. canis larvae in pregnant bitches. The series of complex events that occur during larval reactivation is a clear example of transregulation, in which host hormones regulate the vital functions of the parasite to positively influence its establishment and/or proliferation. Understanding larval reactivation from an immunoendocrine perspective helps us to comprehensively understand the complex parasite-host relationship of T. canis.