Role of TNF-α in human female reproduction

Adverse childhood experiences are associated with increased risk of miscarriage in a national population-based cohort study in England

STUDY QUESTION

Is there an association between adverse childhood experiences (ACE) and the risk of miscarriage in the general population?

SUMMARY ANSWER

Specific ACE as well as the summary ACE score were associated with an increased risk of single and recurrent miscarriages.

WHAT IS KNOWN ALREADY

There is scarce evidence on the association between ACE and miscarriage risk.

STUDY DESIGN, SIZE, DURATION

We conducted a retrospective national cohort study. The sample consisted of 2795 women aged 55-89 years from the English Longitudinal Study of Ageing (ELSA).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Our study was population-based and included women who participated in the ELSA Life History Interview in 2007. We estimated multinomial logistic regression models of the associations of the summary ACE score and eight individual ACE variables (pertaining to physical and sexual abuse, family dysfunction and experiences of living in residential care or with foster parents) with self-reported miscarriage (0, 1, ≥2 miscarriages).

MAIN RESULTS AND THE ROLE OF CHANCE

Five hundred and fifty-three women (19.8% of our sample) had experienced at least one miscarriage in their lifetime. Compared with women with no ACE, women with ≥3 ACE were two times more likely to experience a single miscarriage in their lifetime (relative risk ratio 2.00, 95% CI 1.25-3.22) and more than three times more likely to experience recurrent miscarriages (≥2 miscarriages) (relative risk ratio 3.10, 95% CI 1.63, 5.89) after adjustment for birth cohort, age at menarche and childhood socioeconomic position. Childhood experiences of physical and sexual abuse were individually associated with increased risk of miscarriage.

LIMITATIONS, REASONS FOR CAUTION

Given the magnitude of the observed associations, their biological plausibility, temporal order and consistency with evidence suggesting a positive association between ACE and adverse reproductive outcomes, it is unlikely that our findings are spurious. Nevertheless, the observed associations should not be interpreted as causal as our study was observational and potentially susceptible to bias arising from unaccounted confounders. Non-response and ensuing selection bias may have also biased our findings. Retrospectively measured ACE are known to be susceptible to underreporting. Our study may have misclassified cases of ACE and possibly underestimated the magnitude of the association between ACE and the risk of miscarriage.

WIDER IMPLICATIONS OF THE FINDINGS

Our study highlights experiences of psychosocial adversity in childhood as a potential risk factor for single and recurrent miscarriages. Our findings contribute to a better understanding of the role of childhood trauma in miscarriage and add an important life course dimension to the study of miscarriage.

STUDY FUNDING/COMPETING INTEREST(S)

ELSA is currently funded by the National Institute on Aging in USA (R01AG017644) and a consortium of UK government departments coordinated by the National Institute for Health Research. The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the article. The authors have no actual or potential competing financial interests to disclose.

Transcriptomic profiling of progesterone in the male fathead minnow (Pimephales promelas) testis

P4 is a hormone with diverse functions that include roles in reproduction, growth, and development. The objectives of this study were to examine the effects of P4 on androgen production in the mature teleost testis and to identify molecular signaling cascades regulated by P4 to improve understanding of its role in male reproduction. Fathead minnow (FHM) testis explants were treated in vitro with two concentrations of P4 (10(-8) and 10(-6) M) for 6 and 12 h. P4 significantly increased testosterone (T) production in the FHM testis but did not affect 11-ketotestosterone. Gene network analysis revealed that insulin growth factor (Igf1) and tumor necrosis factor receptor (Tnfr) signaling was significantly depressed with P4 treatment after 12h. There was also a 20% increase in a gene network for follicle-stimulating hormone secretion and an 18% decrease in genes involved in vasopressin signaling. Genes in steroid metabolism (e.g. star, cyp19a, 11bhsd) were not significantly affected by P4 treatments in this study, and it is hypothesized that pre-existing molecular machinery may be more involved in the increased production of T rather than the de novo expression of steroid-related transcripts and receptors. There was a significant decrease in prostaglandin E synthase 3b (cytosolic) (ptges3b) after treatment with P4, suggesting that there is cross talk between P4 and prostaglandin pathways in the reproductive testis. P4 has a role in regulating steroid production in the male testis and may do so by modulating gene networks related to endocrine pathways, such as Igf1, Tnfr, and vasopressin.

The role of cytokines in skin aging

Cutaneous aging is one of the major noticeable menopausal complications that most women want to fight in their quest for an eternally youthful skin appearance. It may contribute to some maladies that occur in aging which, despite not being life-threatening, affect the well-being, psychological state and quality of life of aged women. Skin aging is mainly affected by three factors: chronological aging, decreased levels of estrogen after menopause, and environmental factors. Aged skin is characterized by a decrease in collagen content and skin thickness which result in dry, wrinkled skin that is easily bruised and takes a longer time to heal. Cytokines play a crucial role in the manifestation of these features of old skin. The pro-inflammatory cytokine tumor necrosis factor-alpha inhibits collagen synthesis and enhances collagen degradation by increasing the production of MMP-9. It also lowers the skin immunity and thus increases the risk of cutaneous infections in old age. Deranged levels of several interleukins and interferons also affect the aging process. The high level of CCN1 protein in aged skin gives dermal fibroblasts an 'age-associated secretory phenotype' that causes abnormal homeostasis of skin collagen and leads to the loss of the function and integrity of skin. Further research is required especially to establish the role of cytokines in the treatment of cutaneous aging.

Cellular and molecular evidence for a role of tumor necrosis factor alpha in the ovulatory mechanism of trout

BACKGROUND

The relevance of immune-endocrine interactions to the regulation of ovarian function in teleosts is virtually unexplored. As part of the innate immune response during infection, a number of cytokines such as tumor necrosis factor alpha (TNF alpha) and other immune factors, are produced and act on the reproductive system. However, TNF alpha is also an important physiological player in the ovulatory process in mammals. In the present study, we have examined for the first time the effects of TNF alpha in vitro in preovulatory ovarian follicles of a teleost fish, the brown trout (Salmo trutta).

METHODS

To determine the in vivo regulation of TNF alpha expression in the ovary, preovulatory brook trout (Salvelinus fontinalis) were injected intraperitoneally with either saline or bacterial lipopolysaccharide (LPS). In control and recombinant trout TNF alpha (rtTNF alpha)-treated brown trout granulosa cells, we examined the percentage of apoptosis by flow cytometry analysis and cell viability by propidium iodide (PI) staining. Furthermore, we determined the in vitro effects of rtTNF alpha on follicle contraction and testosterone production in preovulatory brown trout ovarian follicles. In addition, we analyzed the gene expression profiles of control and rtTNF alpha-treated ovarian tissue by microarray and real-time PCR (qPCR) analyses.

RESULTS

LPS administration in vivo causes a significant induction of the ovarian expression of TNF alpha. Treatment with rtTNF alpha induces granulosa cell apoptosis, decreases granulosa cell viability and stimulates the expression of genes known to be involved in the normal ovulatory process in trout. In addition, rtTNF alpha causes a significant increase in follicle contraction and testosterone production. Also, using a salmonid-specific microarray platform (SFA2.0 immunochip) we observed that rtTNF alpha induces the expression of genes known to be involved in inflammation, proteolysis and tissue remodeling. Furthermore, the expression of kallikrein, TOP-2, serine protease 23 and ADAM 22, genes that have been postulated to be involved in proteolytic and tissue remodeling processes during ovulation in trout, increases in follicles incubated in the presence of rtTNF alpha.

CONCLUSIONS

In view of these results, we propose that TNF alpha could have an important role in the biomechanics of follicle weakening, ovarian rupture and oocyte expulsion during ovulation in trout, primarily through its stimulation of follicular cell apoptosis and the expression of genes involved in follicle wall proteolysis and contraction.