Tofacitinib restores the balance of gamma delta Treg/gamma delta T17 cells in rheumatoid arthritis by inhibiting the NLRP3 inflammasome
Authors: Yang, Xinyu; Zhan, Ning; Jin, Yang; Ling, Hanzhi; Xiao, Chipeng; Xie, Zhen; Zhong, Hao; Yu, Xinxin; Tang, Runhua; Ma, Jinglan; Guan, Jubo; Yin, Guoyu; Wu, Gan; Lu, Liangjing; Wang, Jianguang
Objective: Tofacitinib (TOF) is a Janus kinase (JAK) inhibitor used in the treatment of rheumatoid arthritis (RA), but the mechanism of its action remains unclear. In this study, we investigated the influence of TOF on gamma delta regulatory T-cell (gamma delta Treg)/gamma delta T17 cell balance in RA and the role of the nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) inflammasome in this process. Methods: We detected levels of inflammatory factors in the serum of RA patients before and after administration of TOF using an enzyme-linked immunosorbent assay (ELISA). A collagen-induced arthritis (CIA) model was constructed to investigate the effect of TOF on arthritis symptoms, gamma delta Treg/gamma delta T17 cell balance and the NLRP3 inflammasome. We used bone marrow-derived macrophages (BMDMs) to study the effect of TOF on NLRP3 inflammasome activation. Nlrp3(-/-) mice were introduced to assess the influence of NLRP3 on.dT17 cell activation in RA. Results: TOF treatment decreased levels of gamma delta T17 cell-related cytokine interleukin-17 (IL-17) in RA patients. In addition, TOF intervention in the CIA model reduced joint inflammation and damage, rebalanced the gamma delta Treg/gamma delta T17 cell ratio and inhibited excessive NLRP3 inflammasome activation in draining lymph nodes and arthritic joints. BMDM intervention experiments demonstrated that TOF decreased the level of secreted IL-1 beta via downregulation of NLRP3. Furthermore, experiments using Nlrp3(-/-) mice verified that the NLRP3 inflammasome mediated the effect of TOF on gamma delta T17 cell activation. Conclusions: Recovery of gamma delta Treg/gamma delta T17 cell balance was a novel mechanism by which TOF alleviated RA. Meanwhile, NLRP3 played a pivotal role in the process of TOF-mediated gamma delta T17 cell activation.
Chronic exposure of BPA impairs male germ cell proliferation and induces lower sperm quality in male mice
Authors: Liu, XueXia; Wang, ZhiXin; Liu, Fujun
Background: Bisphenol A (BPA) is a well-known endocrine disruptor that affects male fertility. However, the main biological events through which BPA affects spermatogenesis remain to be identified. Methods: Adult male mice were treated by feeding with drinking water containing BPA (0.2 mu g/ml, 20 mu g/ml, 200 mu g/ml, respectively) for two months. Testes were collected for protein extraction or for immunohistochemical analysis. Epididymal spermatozoa were collected for sperm quality evaluation and male fertility assay by in vitro fertility (IVF). Serums were collected for detection of testosterone levels. Proteins associated with germ cell proliferation, meiosis, blood-testis barrier, and steroidogenesis production were examined in BPA-treated and control mice testes. CCK8 assay was used to detect the effect of BPA on the proliferation of GC-1 and GC-2 cells. Results: The BPA-treated mice were characterized by decreased sperm quality, serum testosterone levels and, sub-fertile phenotype characterizing with low pregnancy rates and reduced fertilization efficiency. In lower BPA (0.2 mu g/ml) treatment, PCNA and PLZF were down-expressed that indicated impaired germ cell proliferation. SYCP3 was down-expressed in BPA-treated mice, but expressions of other proteins associated with meiosis and blood-testis barrier were not significantly altered. CYP11A1 and HSD3B1 were down-expressed in BPA-treated mice that demonstrated reduced steroidogenesis activity. BPA has a concentration-dependent inhibition effect on the proliferation of GC-1 and GC-2 cells. Conclusively, low doses BPA exposure reduced mice sperm quality mainly by impairing germ cell proliferation, leading to reduced male fertility. The study would provide relevant information for investigation on molecular mechanisms and protective strategy on male production. (C) 2020 Elsevier Ltd. All rights reserved.