Sustained activation of NLRP3 inflammasome is closely related to diabetes and stroke. However, it is unknown whether NLRP3 inflammasome plays an essential role in stroke in diabetes. We aim to investigate the effect and the potential mechanism of NLRP3 inflammasome in diabetic mice with cerebral ischemia-reperfusion injury. A type 2 diabetic mouse model was induced by a high-fat diet and streptozotocin (STZ). Diabetic mice received MCC950 (the specific molecule NLRP3 inhibitor) or vehicle 60 minutes before the middle cerebral artery occlusion (MCAO) and reperfusion. MCC950 reduced the neurological deficit score of 24 h after cerebral ischemia reperfusion and improved the 28-day survival rate of cerebral ischemia-reperfusion injury in diabetic mice. Furthermore, we found that the mRNA transcription levels of NLRP3, IL-1β, and caspase-1 in the core ischemic area were remarkably amplified in diabetic mice with cerebral ischemia-reperfusion injury, whereas this phenomenon was obviously attenuated by MCC950 pretreatment. In conclusion, the NLRP3 inflammasome was involved in the complex diseases of diabetic stroke. MCC950, the NLRP3 specific inhibitor, ameliorated diabetic mice with cerebral ischemia-reperfusion injury and improved the 28-day survival rate during the recovery stage of ischemic stroke.

The interleukin-1 family of cytokines are potent inducers of inflammation and pain. Proteolytic activation of this family of cytokines is under the control of several innate immune receptors that coordinate to form large multiprotein signalling platforms, termed inflammasomes. Recent evidence suggests that a wide range of inflammatory diseases, cancers, and metabolic and autoimmune disorders, in which pain is a common complaint, may be coordinated by inflammasomes. Activation of inflammasomes results in cleavage of caspase-1, which subsequently induces downstream initiation of several potent pro-inflammatory cascades. Therefore, it has been proposed that targeting inflammasome activity may be a novel and effective therapeutic strategy for these pain-related diseases. The purpose of this narrative review article is to provide the reader with an overview of the activation and regulation of inflammasomes and to investigate the potential therapeutic role of inflammasome inhibition in the treatment of diseases characterized by pain, including the following: complex regional pain syndrome, gout, rheumatoid arthritis, inflammatory pain, neuropathic pain, chronic prostatitis, chronic pelvic pain syndrome, and fibromyalgia. We conclude that the role of the inflammasome in pain-associated diseases is likely to be inflammasome subtype and disease specific. The currently available evidence suggests that disease-specific targeting of the assembly and activity of the inflammasome complex may be a novel therapeutic opportunity for the treatment of refractory pain in many settings.

Local anaesthetics (LAs) may lead to neurological complications, but the underlying mechanism is still unclear. Many neurotoxicity research studies have examined different LAs, but none have comprehensively explored the distinct mechanisms of neurotoxicity caused by amide- (bupivacaine) and ester- (procaine) type LAs. Here, based on a CCK8 assay, LDH assay, Rhod-2-AM and JC-1 staining, 2′,7′-dichlorohy-drofluorescein diacetate and dihydroethidium probes, an alkaline comet assay, and apoptosis assay, we show that both bupivacaine and procaine significantly induce mitochondrial calcium overload and a decline in the mitochondrial membrane potential as well as overproduction of ROS, DNA damage and apoptosis (P < 0.05). There were no significant differences in mitochondrial injury and apoptosis between the bupivacaine and procaine subgroups (P > 0.05). However, to our surprise, the superoxide anionic level after treatment with bupivacaine, which leads to more severe DNA damage, was higher than the level after treatment with procaine, while procaine produced more peroxidation than bupivacaine. Some of these results were also affirmed in dorsal root ganglia neurons of C57 mice. The differences in the superoxidation and peroxidation induced by these agents suggest that different types of LAs may cause neurotoxicity via different pathways. We can target more accurate treatment based on their different mechanisms of neurotoxicity.

Background: Chronic stress is well known to promote tumor progression, however, little is known whether chronic stress-mediated regulation of osteoblasts contributes to the migration and invasion of metastatic cancer cells. Methods: The proliferation, migration and invasion of prostate cancer cells were assessed by CCK-8 and transwell assay. HIF-1α expression of osteoblasts and epithelial-mesenchymal transition (EMT) markers of prostate cancer cells were examined by Western blot. The mRNA level of cytokines associated with bone metastasis in osteoblasts and EMT markers in PC-3 and DU145 cells were performed by qRT-PCR. Functional rescue experiment of cells were performed by using siRNA, plasmid transfection and inhibitor treatment. Results: Isoproterenol (ISO), a pharmacological surrogate of sympathetic nerve activation induced by chronic stress, exhibited no direct effect on migration and invasion of PC-3 and DU145 prostate cancer cells. Whereas, osteoblasts pretreated with ISO promoted EMT, migration and invasion of PC-3 and DU145 cells, which could be inhibited by β2AR inhibitor. Mechanistically, ISO increased the secretion of CXCL12 via the β2AR-HIF-1α signaling in osteoblasts. Moreover, overexpression of HIF-1α osteoblasts promoted migration and invasion of PC-3 and DU145 cells, which was inhibited by addition of recombinant knockdown of CXCR4 in PC-3 and DU145 cells, and inhibiting CXCL12-CXCR4 signaling with LY2510924 blunted the effects of osteoblasts in response to ISO on EMT and migration as well as invasion of PC-3 and DU145 cells. Conclusions: These findings demonstrated that β2AR-HIF-1α-CXCL12 signaling in osteoblasts facilitates migration and invasion as well as EMT of prostate cancer cells, and may play a potential role in affecting bone metastasis of prostate cancer.

Bupivacaine, a commonly used local anesthetic, has potential neurotoxicity through diverse signaling pathways. However, the key mechanism of bupivacaine‐induced neurotoxicity remains unclear. Cultured human SH‐SY5Y neuroblastoma cells were treated (bupivacaine) or untreated (control) with bupivacaine for 24 h. Compared to the control group, bupivacaine significantly increased cyto‐inhibition, cellular reactive oxygen species, DNA damage, mitochondrial injury, apoptosis (increased TUNEL‐positive cells, cleaved caspase 3, and Bcl‐2/Bax), and activated autophagy (enhanced LC3II/LC3I ratio). To explore changes in protein expression and intercommunication among the pathways involved in bupivacaine‐induced neurotoxicity, an 8‐plex iTRAQ proteomic technique and bioinformatics analysis were performed. Compared to the control group, 241 differentially expressed proteins were identified, of which, 145 were up‐regulated and 96 were down‐regulated. Bioinformatics analysis of the cross‐talk between the significant proteins with altered expression in bupivacaine‐induced neurotoxicity indicated that phosphatidyl‐3‐kinase (PI3K) was the most frequently targeted protein in each of the interactions. We further confirmed these results by determining the downstream targets of the identified signaling pathways (PI3K, Akt, FoxO1, Erk, and JNK). In conclusion, our study demonstrated that PI3K may play a central role in contacting and regulating the signaling pathways that contribute to bupivacaine‐induced neurotoxicity.