Terminal Deoxyribonucleotide Transferase-mediated Nick End Research Articles

Polystyrene microplastics lead to pyroptosis and apoptosis of ovarian granulosa cells via NLRP3/Caspase-1 signaling pathway in rats

Microplastics (MPs) considered as a new persistent environmental pollutant could enter into the circulatory system and result in decrease of sperm quantity and quality in mice. However, the effects of Polystyrene MPs (PS MPs) on the ovary and its mechanism in rats remained unclear. In this present study, thirty-two healthy female Wistar rats were exposed to different concentrations of 0.5 µm PS MPs dispersed in deionized water for 90 days. Using hematoxylin-eosin (HE) staining, the number of growing follicles was decreased compared to the control group. In addition, the activity of glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) were decreased while the expression level of malondialdehyde (MDA) was increased in ovary tissue. Confirmed by immunohistochemistry, the integrated optical density of NLRP3 and Cleaved-Caspase-1 had been elevated by 13.9 and 14 in granulosa cells in the 1.5 mg/kg/d group. Furthermore, compared to the control group, the level of AMH had been decreased by 23.3 pg/ml while IL-1β and IL-18 had been increased by 32 and 18.5 pg/ml in the 1.5 mg/kg/d group using the enzyme-linked immune sorbent assay (ELISA). Besides, the apoptosis of granulosa cells was elevated measured by terminal deoxyribonucleotide transferase-mediated nick end labeling (TUNEL) staining and flow cytometry. Moreover, western blot assays showed that the expressions of NLRP3/Caspase-1 signaling pathway related factors and Cleaved-Caspase-3 were increased. These results demonstrated that PS MPs could induce pyroptosis and apoptosis of ovarian granulosa cells via the NLRP3/Caspase-1 signaling pathway maybe triggered by oxidative stress. The present study suggested that exposure to microplastics had adverse effects on ovary and could be a potential risk factor for female infertility, which provided new insights into the toxicity of MPs on female reproduction.

Naoluo Xintong capsule ameliorates apoptosis induced by endoplasmic reticulum stress in rats with cerebral ischemia/ reperfusion injury

Naoluo Xintong (NLXT) capsuleis a newly developed drug recorded in the Chinese Pharmacopoeia. It is derived from traditional Chinese medicine (TCM) NLXT decoction, and has been widely used to treat cerebrovascular diseases in clinic. However, it is currently unknown whether it improve cerebral ischemia reperfusion (I/R) injury. The effect of NLXT on regional cerebral blood flow (rCBF) was examined using Laser Doppler flower. The Terminal deoxyribonucleotide transferase-mediated Nick end labeling (Tunel) assay was performed to determine the effects of NLXT on apoptosis. Subsequently, cerebral water content and TTC staining were measured to assess cerebral edema and infarct volume, respectively. The protein expression levels were analyzed with Immunofluorescence and western blot assays. The results indicated that NLXT ameliorated MCAO-induced cerebral I/R injury by decreasing infract volume, inhibition of apoptosis, and upregulation rCBF. In addition, it decreased the expression of key protein involved endoplasmic reticulum (ER)-stress, including glucose-regulated protein 78 (GRP78), C/EBP-homologous protein (CHOP) and Caspase-12 at 24 h following reperfusion. This was accompanied reduced degradation level of TRPC6 and increased phosphorylation of cAMP/Ca2+ response elementbinding protein (p-CREB), and decreased calpain-specific αII-spectrin breakdown product (SBDP145) activity. Interestingly, inhibition of mitogen-activated protein kinase (MEK) activity abolished the effect of NLXT on CREB activity. Collectively, the results indicated that NLXT can improve I/R injury therapy by activating TRPC6/MEK/CREB signaling pathway to attenuate ER-stress related neuronal apoptosis.