Protective effects of leonurine hydrochloride on pyroptosis in premature ovarian insufficiency via regulating NLRP3/GSDMD pathway.

Premature ovarian insufficiency is common in clinically infertile patients. The NOD-like receptor family pyrin domain-containing 3 (NLRP3)/Gasdermin D (GSDMD) signaling pathway plays a key role in premature ovarian insufficiency. Leonurine (Leo) is one of the important active ingredients extracted from Leonurus japonicus Houttuyn, which can inhibit NLRP3 activation. However, whether leonurine hydrochloride plays a protective role in premature ovarian insufficiency through actions on NLRP3/GSDMD signaling is not yet known. After cyclophosphamide-induced premature ovarian insufficiency was established in female mice, Leo was injected intraperitoneally over four weeks to evaluate the ovarian function and anti-pyroptosis effects using the metrics of fertility, serum hormone level, ovary weight, follicle number, expression of NLRP3/GSDMD pathway-related proteins, and serum IL-18 and IL-1β levels. Intraperitoneal administration of leonurine hydrochloride was found to significantly protect fertility and maintain both serum hormone levels and follicle number in mice with premature ovarian insufficiency. Mice treated with leonurine hydrochloride consistently resisted cyclophosphamide-induced ovarian damage by inhibiting the activation of NLRP3 inflammasome, Caspase-1 and GSDMD in both ovarian tissue and granulosa cells, which led to lower levels of IL-18 and IL-1β in the serum (p < 0.05, p < 0.01, p < 0.001). Intraperitoneal administration of leonurine hydrochloride prevents cyclophosphamide-induced premature ovarian insufficiency in mice by inhibiting NLRP3/GSDMD-mediated pyroptosis.

Chi YN ，Hai DM ，Ma L ，Cui YH ，Hu HT ，Liu N ，Juan-Du ，Lan XB ，Yu JQ ，Yang JM ... -  《-》

α-Ketoglutarate Improves Ovarian Reserve Function in Primary Ovarian Insufficiency by Inhibiting NLRP3-Mediated Pyroptosis of Granulosa Cells.

Premature ovarian insufficiency (POI) is a common female infertility problem, with its pathogenesis remains unknown. The NOD-like receptor family pyrin domain-containing 3 (NLRP3)-mediated pyroptosis has been proposed as a possible mechanism in POI. This study investigates the therapeutic effect of α-ketoglutarate (AKG) on ovarian reserve function in POI rats and further explores the potential molecular mechanisms. POI rats are caused by administration of cyclophosphamide (CTX) to determine whether AKG has a protective effect. AKG treatment increases the ovarian index, maintains both serum hormone levels and follicle number, and improves the ovarian reserve function in POI rats, as evidence by increased the level of lactate and the expression of rate-limiting enzymes of glycolysis in the ovaries, additionally reduced the expression of NLRP3, Gasdermin D (GSDMD), Caspase-1, Interleukin-18 (IL-18), and Interleukin-1 beta (IL-1β). In vitro, KGN cells are treated with LPS and nigericin to mimic pyroptosis, then treated with AKG and MCC950. AKG inhibits inflammatory and pyroptosis factors such as NLRP3, restores the glycolysis process in vitro, meanwhile inhibition of NLRP3 has the same effect. AKG ameliorates CTX-induced POI by inhibiting NLRP3-mediated pyroptosis, which provides a new therapeutic strategy and drug target for clinical POI patients.

Liu K ，Wu Y ，Yang W ，Li T ，Wang Z ，Xiao S ，Peng Z ，Li M ，Xiong W ，Li M ，Chen X ，Zhang S ，Lei X ... -  《-》

[Huangdi Anxiao Capsules-containing serum protects cell model from cognitive dysfunction in diabetes via inhibiting NLRP3-mediated pyroptosis].

Wang XJ ，Wang YL ，Shao N ，Ye T ，Ye S ，Gao HW ，Wang Y ... -  《-》

Berberine ameliorates pulmonary inflammation in mice with influenza viral pneumonia by inhibiting NLRP3 inflammasome activation and gasdermin D-mediated pyroptosis.

Viral pneumonia is a common complication caused by Influenza A virus infection and is characterized by severe pulmonary inflammation. A previous study showed that berberine (BBR) significantly ameliorated the pulmonary inflammation in mice with influenza viral pneumonia but its underlying mechanism is not entirely understood. In this study, we reproduced the mouse model of influenza viral pneumonia through intranasal infection of A/Puerto Rico/8/34 (H1N1), to further investigate the anti-inflammatory mechanism of BBR based on nucleotide-binding oligomerization domain-like receptor protein (NLRP) 3 inflammasome activation and Gasdermin D (GSDMD)-mediated pyroptosis. Consistent with MCC950 (10 mg/kg, a specific NLRP3 inflammasome inhibitor), BBR (10 mg/kg) obviously improved the weight loss and survival rate of infected mice, alleviated their pulmonary inflammation, and suppressed the accumulation of tumor necrosis factor and interleukin (IL)-6 in lungs without obvious inhibition on viral multiplication (hemagglutinin titer and nucleoprotein messenger RNA). Moreover, BBR (10 mg/kg) reduced the expressions of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), and cysteinyl aspartate-specific proteinase (Caspase)1 (Caspase1 precursor [Pro-caspase1] + Caspase1p20 subunit) and the ratio of Caspase1p20 subunit to Caspase1, thus inhibiting the NLRP3 inflammasome activation and resulting in the decreased contents of mature IL-1β and IL-18 in lungs. The GSDMD expression (GSDMD precursor [Pro-GSDMD] + GSDMD-N terminal [NT]) and the ratio of GSDMD-NT to GSDMD were also declined by BBR (10 mg/kg). These evidence indicate that BBR may ameliorate pulmonary inflammation in mice with influenza viral pneumonia through inhibiting NLRP3 inflammasome activation, as well as depressing GSDMD-mediated pyroptosis via declining GSDMD expression and restraining NLRP3 inflammasome-mediated GSDMD activation.

An C ，Wu Y ，Wu J ，Liu H ，Zhou S ，Ge D ，Dong R ，You L ，Hao Y ... -  《-》

Suppression of the caspase-1/GSDMD-mediated pyroptotic signaling pathway through dexamethasone alleviates corneal alkali injuries.

The pathological mechanism of corneal injuries mediated by alkali burns are associated with Nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain containing 3 protein (NLRP3)-related corneal sterile inflammation. Whether the executive protein gasdermin D (GSDMD) of pyroptosis mediated by the NLRP3 inflammasome is present in alkali-induced corneal lesions remains unclear. Dexamethasone (Dex) is a commonly used drug for ocular surface diseases that can maintain corneal transparency and anti-inflammatory effects by topical administration. Here, we presented evidence that the effect of Dex on the pyroptosis-related caspase-1/GSDMD pathway in corneal alkali burns (CABs). We assessed the clinical manifestations and histological characteristics of the placebo group, 0.05% Dex group, 0.1% Dex group on day 3 or day 7 postburn and the control group (healthy corneas). The expression of factors (including NLRP3, caspase-1, cleaved-caspase-1, GSDMD, GSDMD-N termini, pro-interleukin(IL)-1β, IL-1β, pro-IL-18 and IL-18) involved in the pyroptosis related caspase-1/GSDMD signaling pathway was demonstrated by molecular experiments in CAB. Alkali burns can upregulate the originally relatively dim expression of NLRP3, caspase-1, cleaved-caspase-1, GSDMD, GSDMD-N, pro-IL-1β, pro-IL-18, IL-1β and IL-18 in the healthy corneal epithelium and stroma. However, Dex can reverse the enhanced expression at the two timepoints. Corneal sterile inflammation can activate the NLRP3 inflammasome through the innate immune response mechanism and then activate the pyroptosis-related caspase-1/GSDMD signaling pathway. In addition, Dex can inhibit pyroptosis through this pathway.

Tan Y ，Zhang M ，Pan Y ，Feng H ，Xie L ... -  《-》