Immunohistochemical expression of hypoxia-inducible factor-1α in stromal cells of vaginal tissue in post-menopausal women with pelvic organ prolapse

Genetic Etiology in Pelvic Organ Prolapse: Role of Connective Tissue Homeostasis, Hormone Metabolism, and Oxidative Stress

Background: Pelvic organ prolapse (POP) has become a common health problem among the aging population and affects an increasing number of elderly women worldwide. Studies within family and twin pairs provided strong evidence for the contribution of genetic factors to POP. Given the incomplete penetrance, polygenic traits, and small effect sizes of each variant in complex diseases, it is not always easy to evaluate the genetic susceptibility and molecular mechanisms involved in POP. Objectives: This review intends to comprehensively summarize the current studies on genetic variants associated with POP. Methods: We performed a comprehensive review to summarize the genetic findings from genome-linkage studies, genome-wide association studies, candidate association studies, and gene expression analyses. Results: We summarized genetic variants associated with connective tissue homeostasis, hormone metabolism, and oxidative stress, which were potentially related to the pathophysiology of POP. We also reviewed the limited polygenic risk score (PRS) studies generated for each individual's genetic risk stratification and its integration into clinical risk factors for disease prediction. Conclusions: This pooled analysis provides moderate epidemiological credibility for associations of these genetic variants with POP to bridge the gap between genetic research and clinical medicine towards understanding the genetic etiology of POP. It also highlights the potential of PRS as a risk prediction model.

Hypoxia-Inducible Factor 1 Alpha Is Dispensable for Host Defense of Group B Streptococcus Colonization and Infection

Group B Streptococcus (GBS) is a leading cause of neonatal morbidity and mortality, and the primary source of exposure is the maternal vagina. Intrapartum antibiotic prophylaxis for GBS-positive mothers has reduced the incidence of GBS early-onset disease, however, potential long-lasting influence of an antibiotic-altered neonatal microbiota, and the frequent clinical sequelae in survivors of invasive GBS infection, compels alternative treatment options for GBS. Here, we examined the role of transcription factor hypoxia-inducible factor 1 alpha (HIF-1α), widely recognized as a regulator of immune activation during infection, in the host response to GBS. Given the importance of endogenous HIF-1α for innate immune defense, and the potential utility of HIF-1α stabilization in promoting bacterial clearance, we hypothesized that HIF-1α could play an important role in coordinating host responses to GBS in colonization and systemic disease. Counter to our hypothesis, we found that GBS infection did not induce HIF-1α expression in vaginal epithelial cells or murine macrophages, nor did HIF-1α deficiency alter GBS colonization or pathogenesis in vivo. Furthermore, pharmacological enhancement of HIF-1α did not improve control of GBS in pathogenesis and colonization models, while displaying inhibitory effects in vaginal epithelial cytokines and immune cell killing in vitro. Taken together, we conclude that HIF-1α is not a prominent aspect of the host response to GBS colonization or invasive disease, and its pharmacological modulation is unlikely to provide significant benefit against this important neonatal pathogen.

Mouth breathing impairs the development of temporomandibular joint at a very early stage

OBJECTIVES

The study aimed to explore the effects of mouth breathing and hypoxia on the condyle of temporomandibular joint (TMJ) via two animal models.

METHODS

24 four-week-old rats were randomly separated into three groups, consisting of eight control rats, eight intermittent hypoxia (IH) rats, and eight intermittent nasal obstruction (INO) rats. We use the IH model and the INO model to simulate children suffering from hypoxia and mouth breathing. After 16 days, the condyle of TMJ and surrounding white adipose tissue (WAT) and skeletal muscle tissue were obtained for further staining and qRT-PCR. Finally, RNA-seq was used to verify the results.

RESULTS

The intermittent hypoxia cannot significantly change the overall structure in the cause of short-term hypoxia stimulation, but the intermittent nasal obstruction can alter the condyle, WAT, and muscle, while also introducing noticeable structural changes in tissue hypoxia and macrophage infiltration. Sequencing data verified these findings and also suggested that this process might involve the Hif-1α/Vegf axis.

CONCLUSIONS

Our findings reveal the very early structural impact of mouth breathing on condyle reconstruction in rat models, and hypoxia does not induce evident alteration on condyle. However, since these results are mainly focused on rats, further studies are needed to understand its effects on humans.