17β-Estradiol promotes angiogenesis of stria vascular in cochlea of C57BL/6J mice

Quercetin attenuates cisplatin-induced mitochondrial apoptosis via PI3K/Akt mediated inhibition of oxidative stress in pericytes and improves the blood labyrinth barrier permeability

Cisplatin (CDDP) is broadly employed to treat different cancers, whereas there are no drugs approved by the Food and Drug Administration (FDA) for preventing its side effects, including ototoxicity. Quercetin (QU) is a widely available natural flavonoid compound with anti-tumor and antioxidant properties. The research was designed to explore the protective effects of QU on CDDP-induced ototoxicity and its underlying mechanisms in male C57BL/6 J mice and primary cultured pericytes (PCs). Hearing changes, morphological changes of stria vascularis, blood labyrinth barrier (BLB) permeability and expression of apoptotic proteins were observed in vivo by using the auditory brainstem response (ABR) test, HE staining, Evans blue staining, immunohistochemistry, western blotting, etc. Oxidative stress levels, mitochondrial function and endothelial barrier changes were observed in vitro by using DCFH-DA probe detection, flow cytometry, JC-1 probe, immunofluorescence and the establishment in vitro BLB models, etc. QU pretreatment activates the PI3K/AKT signaling pathway, inhibits CDDP-induced oxidative stress, protects mitochondrial function, and reduces mitochondrial apoptosis in PCs. However, PI3K/AKT specific inhibitor (LY294002) partially reverses the protective effects of QU. In addition, in vitro BLB models were established by coculturing PCs and endothelial cells (ECs), which suggests that QU both reduces the CDDP-induced apoptosis in PCs and improves the endothelial barrier permeability. On the whole, the research findings suggest that QU can be used as a novel treatment to reduce CDDP-induced ototoxicity.

Association between blood volatile organic aromatic compound concentrations and hearing loss in US adults

OBJECTIVE

Benzene, ethylbenzene, meta/para-xylene, and ortho-xylene, collectively referred to as benzene, ethylbenzene, and xylene (BEX), constitute the main components of volatile organic aromatic compounds (VOACs) and can have adverse effects on human health. The relationship between exposure to BEX and hearing loss (HL) in the adult U.S. population was aimed to be assessed.

METHODS

Cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) for the years 2003-2004, 2011-2012, and 2015-2016 were analyzed. This dataset included complete demographic characteristics, pure-tone audiometry measurements, and volatile organic compound detection data from the NHANES database. A weighted multivariate logistic regression model was employed to investigate the associations between blood BEX concentrations HL, low-frequency hearing loss (SFHL), and high-frequency hearing loss (HFHL).

RESULTS

2174 participants were included, with weighted prevalence rates of HL, SFHL, and HFHL being 46.81%, 25.23%, and 45.86%, respectively. Exposure to benzene, ethylbenzene, meta/para-xylene, and ortho-xylene, and cumulative BEX concentrations increased the risk of hearing loss (odds ratios [ORs] were 1.36, 1.22, 1.42, 1.23, and 1.31, respectively; all P < 0.05). In the analysis with SFHL as the outcome, ethylbenzene, m-/p-xylene, o-xylene, benzene, and overall BEX increased the risk (OR 1.26, 1.21, 1.28, 1.20, and 1.25, respectively; all P < 0.05). For HFHL, exposure to ethylbenzene, m-/p-xylene, o-xylene, benzene, and overall BEX increased the risk (OR 1.36, 1.22, 1.42, 1.22, and 1.31, respectively; all P < 0.05).

CONCLUSION

Our study indicated that a positive correlation between individual or cumulative exposure to benzene, ethylbenzene, meta/para-xylene, and ortho-xylene and the risk of HL, SFHL, and HFHL. Further research is imperative to acquire a more comprehensive understanding of the mechanisms by which organic compounds, notably BEX, in causing hearing loss and to validate these findings in longitudinal environmental studies.

17β-Estradiol promotes angiogenesis of bone marrow mesenchymal stem cells by upregulating the PI3K-Akt signaling pathway

•

The role and mechanism of 17β -estradiol in the regulation of BMSC promoting angiogenesis were analyzed by bioinformatics techniques for the first time.

•

Combined with FN1, MCM2, XPO1, NTRK1 and other proteins, 17β-estradiol is able to activate PI3K-Akt, MAPK and other signaling pathways to regulate BMSCs to promote or remodel angiogenesis.

•

17β-estradiol upregulates the PI3K-Akt signaling pathway to promote the BMSC angiogenesis process of differentiation.

Objective

Estrogen is an important hormone affecting angiogenesis in women and is important for female physical development. Menopausal women are prone to serious cardiovascular and cerebrovascular diseases when estrogen is significantly reduced. Bone marrow mesenchymal stem cells (BMSC) have potential roles in processes such as angiogenesis and remodeling. This study is to investigate the effect of 17β-estradiol on BMSC angiogenic differentiation and its underlying molecular mechanism, and to provide a basis for the treatment of microvascular diseases.

Methods

Enrichment analysis of apoptosis, migration or angiogenesis processes and molecular mechanisms of BMSC treated with 17β-estradiol was performed to screen core proteins and perform molecular docking validation. Human MSCs were cultured in vitro to examine the effect of 17β-estradiol on BMSC migration or angiogenic differentiation.

Results

17β-estradiol acted on 48 targets of BMSC and was involved in regulating 52 cell migration processes or 17 angiogenesis processes through 66 KEGG pathways such as PI3K-Akt, MAPK, etc. 17β-estradiol bound tightly to 10 core proteins including APP, NTRK1, EGFR, and HSP90AA1. 17β-estradiol promoted cell scratch area closure rate and CD31 expression in BMSCs, downregulated BMSC apoptosis rate, and promoted Akt and p-Akt protein expression in BMSC.

Conclusion

17β-estradiol binds to FN1, MCM2, XPO1, NTRK1 and other proteins to initiate PI3K-Akt, MAPK and other signaling pathways, so as to regulate BMSC to promote or remodel angiogenesis, verifying that 17β-estradiol up-regulates PI3K-Akt signaling pathway to promote BMSC angiogenic differentiation.