Effects of past environmental tobacco smoke exposure on the menstrual cycle and menstrual phase-related symptoms: A cross-sectional study

Menstrual cycle symptomatology during the COVID-19 pandemic: The role of interoceptive sensibility and psychological health

The literature on the COVID-19 pandemic has shown the importance of investigating its impact on mental health during this sensitive period, also in relation to the female menstrual cycle. To this end, interceptive sensibility has emerged as a fundamental construct for studying the mind-body interaction among psychosomatic and pain symptoms, particularly through the distinction between two attentional styles (namely, a "mindful" and a "non-mindful" sensibility). The aim of the following study is to verify the role of mental health and interoceptive sensibility on menstrual symptoms in women of childbearing age, during the pandemic, as well as to identify the specific contribution of the existing dimensions of interoceptive sensibility in the prediction of symptoms' severity. Data were collected through an online survey, for which 5294 women responded on demographic information, menstrual history, symptoms' disturbance, and completed the Italian versions of the GHQ-12 and the MAIA. The analyses showed that symptoms were strongly correlated to either the GHQ-12 and the MAIA subscales Noticing, Emotional Awareness, Trusting and Not-Worrying. This result was further verified via a hierarchical regression, which revealed that the same interoceptive dimensions and mental health strongly predicted the intensity of menstrual symptoms (R² = 0.177, ΔR² = 0.143) compared to other considered dimensions (R² = 0.180, ΔR² = 0.002). Results are partially in line with the premises but suggest that mental health has a strong impact on the experience of the menstrual cycle and that only a few interoceptive dimensions may be relevant in explaining the severity of menstrual symptoms. It is here suggested that noticing internal bodily signals and being aware of emotional states might become dysfunctional if not reconciled with a good ability to self-regulate internal states, but may rather contribute to the perpetuation of the 'vicious cycle' of heightened affective and attentional reactions to interoceptive sensations.

Single-nucleus RNA Sequencing reveals the mechanism of cigarette smoke exposure on diminished ovarian reserve in mice

The systematic toxicological mechanism of cigarette smoke (CS) on ovarian reserve has not been extensively investigated. Female 8-week-old C57BL/6 mice at peak fertility were exposed to CS or indoor air only for 30 days (100 mice per group) and the effects of CS on ovarian reserve were assessed using Single-Nucleus RNA Sequencing (snRNA-seq). In addition, further biochemical experiments, including immunohistochemical staining, ELISA, immunofluorescence staining, transmission electron microscopy, cell counting kit-8 assay, flow cytometry analysis, senescence-associated β-galactosidase staining, and western blotting, were accomplished to confirm the snRNA-seq results. We identified nine main cell types in adult ovaries and the cell-type-specific differentially expressed genes (DEGs) induced by CS exposure. Western blot results verified that down-regulation of antioxidant genes (Gpx1 and Wnt10b) and the steroid biosynthesis gene (Fdx1) occurred in both ovarian tissue and human granulosa cell-like tumor cell line (KGN cells) after CS exposure. Five percent cigarette smoke extract (CSE) effectively stimulated the production of reactive oxygen species (ROS), DNA damage, cellular senescence and markedly inhibited KGN cell proliferation by inducing G1-phase cell cycle arrest. Moreover, down-regulation of Gja1, Lama1 and the Ferroptosis indicator (Gpx4) in granulosa cells plays a significant role in ultrastructural changes in the ovary induced by CS exposure. These observations suggest that CS exposure impaired ovarian follicle reserve might be caused by REDOX imbalance in granulosa cells. The current study systematically determined the damage caused by CS in mouse ovaries and provides a theoretical basis for early clinical prediction, diagnosis and intervention of CS exposure-associated primary ovarian insufficiency (POI), and is of great significance in improving female reproductive health.

Associations between drinking water disinfection byproducts and menstrual cycle characteristics: A cross-sectional study among women attending an infertility clinic

Disinfection byproducts (DBPs) have been shown to alter ovarian steroidogenesis and cause estrous cyclicity disturbance and prolongation in experimental studies, however human studies are lacking. We aimed to evaluate the cross-sectional associations between drinking water DBPs and menstrual cycle characteristics. A total of 1078 women attending an infertility clinic in Wuhan, China were included between December 2018 and January 2020. Characteristics of menstrual cycle were collected by questionnaires. Concentrations of dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were measured in urine as biomarkers of drinking water DBPs. Multivariate logistic and linear regression models were used to evaluate the associations between urinary DCAA and TCAA concentrations and menstrual cycle characteristics. Higher urinary DCAA concentrations were associated with increased odds ratios (ORs) of irregular menstrual cycle (OR = 1.80; 95% CI: 0.97, 3.33 for the highest vs. lowest quartile; P for trend = 0.05) and long menstrual cycle (OR = 1.62; 95% CI: 0.97, 2.70 for the highest vs. lowest quartile; P for trend = 0.06), as well as prolonged variation in cycle length (β = 1.27 days; 95% CI: -0.11, 2.66 for the highest vs. lowest quartile; P for trend = 0.04). Higher urinary TCAA concentrations were associated with prolonged bleeding duration (β = 0.23 days; 95% CI: -0.06, 0.51 for the highest vs. lowest quartile; P for trend = 0.07). These results suggest that exposure to drinking water DBPs is associated with menstrual cycle disturbances. These findings are warranted to confirm in other studies.