Effects of Occupational Noise Exposure on Hearing Loss: Regulatory Effect of Mediterranean Diet.

OBJECTIVE: To assess regulatory effect of Mediterranean diet for occupational noise exposure and hearing loss. Methods: This cross-sectional study included 4757 individuals. Weighted logistic regression model was adopted to explore the association of occupational noise exposure and Mediterranean diet with hearing loss, and regulatory effects of the Mediterranean diet for the relationship of occupational noise exposure and hearing loss. Results: Occupational noise exposure was associated with an increased odds of hearing loss. Under low adherence to the Mediterranean diet, the occupational noise exposure group was related to increased odds of hearing loss. Under high adherence to the Mediterranean diet, no significant difference was observed between occupational noise exposure and hearing loss, and adjusted effect size was reduced accordingly. Conclusion: Mediterranean diet may moderate this relationship of occupational noise exposure and hearing loss to some degree.

Icariside II inhibits lipopolysaccharide-induced inflammation and amyloid production in rat astrocytes by regulating IKK/IκB/NF-κB/BACE1 signaling pathway.

ß-amyloid (Aß) is one of the inducing factors of astrocytes activation and neuroinflammation, and it is also a crucial factor for the development of Alzheimer's disease (AD). Icariside II (ICS II) is an active component isolated from a traditional Chinese herb Epimedium, which has shown to attnuate lipopolysaccharide (LPS)-induced neuroinflammation through regulation of NF-κB signaling pathway. In this study we investigated the effects of ICS II on LPS-induced astrocytes activation and Aß accumulation. Primary rat astrocytes were pretreated with ICS II (5, 10, and 20 µM) or dexamethasone (DXMS, 1 µM) for 1 h, thereafter, treated with LPS for another 24 h. We found that ICS II pretreatment dose dependently mitigated the levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) in the astrocytes. Moreover, ICS II not only exerted the inhibitory effect on LPS-induced IκB-α degradation and NF-κB activation, but also decreased the levels of Aß1-40, Aß1-42, amyloid precursor protein (APP) and beta secretase 1 (BACE1) in the astrocytes. Interestingly, molecular docking revealed that ICS II might directly bind to BACE1. It is concluded that ICS II has potential value as a new therapeutic agent to treat neuroinflammation-related diseases, such as AD.

Heteroclitins R-S: new dibenzocylooctadiene lignans from Kadsura heteroclita.

AIM: To study the dibenzocylooctadiene lignans from the stems of Kadsura heteroclita. METHOD: Chromatographic separations of silica gel and semi-preparative HPLC were used. All of the structures were elucidated on the basis of spectroscopic analysis, including 2D-NMR and HR-MS techniques. RESULTS: Four dibenzocylooctadiene lignans were isolated from K. heteroclita. Their structures were identified as heteroclitin R (1), heteroclitin S (2), gonisin O (3), and schisanlignone A (4). CONCLUSION: Heteroclitin R (1) and heteroclitin S (2) are new natural lignans.