The NLRP3 (nucleotide-binding oligomerization domain-like receptor [NLR] family pyrin domain-containing 3) inflammasome is a member of the NLR family of innate immune cell sensors. These are crucial regulators of cytokine secretions, which promote ischemic cell death and insulin resistance. This review summarizes recent progress regarding the NLRP3 inflammasome as a potential treatment for ischemic stroke in patients with diabetes, two complicated diseases that often occur together. Stroke worsens glucose metabolism abnormalities, and the outcomes after stroke are more serious for diabetic patients compared with those without diabetes. Inflammation contributes to organ injury after ischemic stroke and diabetes. Recent research has focused on inhibiting the activation of inflammasomes and thus reducing the maturation of proinflammatory cytokines such as interleukin (IL)-1β and IL-18. Studies suggest that inhibition of NLRP3 prevents or alleviates both ischemic stroke and diabetes. Targeting against the assembly and activity of the NLRP3 inflammasome is a potential and novel therapy for inflammasome-associated diseases, including ischemic stroke concomitant with diabetes.

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.

Pyruvate kinase M2 (PKM2) is a key enzyme of glycolysis, which is highly expressed in many tumor cells, and has emerged as an important player in tumor progression and metastasis. However, the functional roles of PKM2 in tumor metastasis remain elusive. Here we showed that PKM2 promoted prostate cancer metastasis via extracellularregulated protein kinase (ERK)-cyclooxygenase (COX-2) signaling. Based on public databases, we found that PKM2 expression was upregulated in prostate cancer and positively associated with tumor metastasis. Further analysis showed that PKM2 promoted prostate cancer cell migration/invasion and epithelial-mesenchymal transition (EMT) through upregulation of COX-2. Mechanistically, PKM2 interacted with ERK1/2 and regulated its phosphorylation, leading to phosphorylation of transcription factor c-Jun, downstream of ERK1/2, to activate COX-2 transcription by IP and ChIP assay, while inhibition of COX-2 significantly reversed the promotion effect of PKM2 on tumor metastasis in vivo. Taken together, our results suggest that a novel of PKM2-ERK1/2c-Jun-COX-2 axis is a potential target in controlling prostate cancer metastasis.