AIM:To investigate the mechanism by which exosomes(EXOs)derived from neural stem cells(NSCs)pretreated with astragaloside IV(ASIV)alleviate brain damage in rats after ischemic stroke.METHODS:Rat NSCs were isolated from fetal rats within 24 h of birth,cultured for 3 d,and subsequently treated with ASIV for additional 5 d.The EXOs from untreated NSCs and ASIV-pretreated NSCs(ASIV-EXOs)were isolated via ultracentrifugation of the cell supernatant.These EXOs were characterized using Western blot to detect specific markers such as CD63,tumor sus-ceptibility gene 101(TSG101)and calnexin.Nanoparticle analysis was employed to determine the size,and the morpholo-gy of the EXOs was observed under electron microscope.Six to eight-week-old SD male rats were randomly assigned to 6 groups:sham group,middle cerebral artery occlusion/reperfusion(MCAO/R)model group,edaravone(EDA)treatment(MCAO/R+EDA)group,EXOs treatement(MCAO/R+EXOs)group and ASIV-EXOs treatment(MCAO/R+ASIV-EXOs)group.Tail vein injections were administered within 2 h following the successful establishment of the MCAO/R model.The Zea Longa method was utilized to evaluate neurological deficits,while the TTC method was employed to assess brain infarc-tion.Pathological changes were examined through HE staining,and TUNEL and caspase-1 immunofluorescence double staining were conducted to detect cellular pyroptosis.Serum levels of interleukin-1β(IL-1β)and IL-18 were measured us-ing ELISA,and Western blot was performed to evaluate the expression of caspase-1,nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3),apoptosis-associated speck-like protein containing a caspase recruitment domain(ASC),gasdermin D(GSDMD),and IL-18 proteins in the ischemic area of the rat cerebral cortex across all groups.RE-SULTS:The MCAO/R group exhibited significantly higher neurological deficit scores compared to the sham group(P＜0.01)and lower scores in the administered groups relative to the MCAO/R group(P＜0.05).Cerebral infarction was mark-edly increased in the MCAO/R group compared to the sham group(P＜0.01),whereas the infarction area was reduced in the administered groups compared to the MCAO/R group(P＜0.05).Serum levels of IL-1β and IL-18 were significantly el-evated in the MCAO/R group versus the sham group(P＜0.01)and were lower in the administered groups compared to the MCAO/R group(P＜0.01).Moreover,IL-1β and IL-18 levels in the MCAO/R+ASIV-EXOs group were lower than those in the MCAO/R+EXOs group(P＜0.05).HE staining revealed pronounced sieve-like infarction foci in the ischemic area of the rat cerebral cortex in MCAO/R group,characterized by disorganized neuronal arrangements,reduced or absent Nys-trom's vesicles,shrunken or fragmented nuclei,and numerous red neurons.In contrast,drug-treated groups exhibited milder pathological changes with clearer neuronal structures and a significant reduction in red neuron counts.Immunofluo-rescence double staining indicated a significant increase in double-positive cells in the MCAO/R group compared to the sham group(P＜0.01),with a decrease in double-positive cells in the administered groups relative to the MCAO/R group(P＜0.05)and a further reduction in the MCAO/R+ASIV-EXOs group compared to the MCAO/R+EXOs group(P＜0.05).The expression levels of caspase-1,NLRP3,ASC,IL-18 and GSDMD proteins in the ischemic region of the rat cerebral cortex were significantly reduced in the administered groups compared to the MCAO/R group(P＜0.01),with further re-duction observed in the MCAO/R+ASIV-EXOs group compared to the MCAO/R+EXOs group(P＜0.05).CONCLU-SION:Exosomes derived from ASIV-pretreated NSCs attenuate brain damage in ischemic stroke rats,potentially through a mechanism involving the inhibition of pyroptosis mediated by the NLRP3/caspase-1 pathway.

AIM:To investigate the mechanism by which exosomes(EXOs)derived from neural stem cells(NSCs)pretreated with astragaloside IV(ASIV)alleviate brain damage in rats after ischemic stroke.METHODS:Rat NSCs were isolated from fetal rats within 24 h of birth,cultured for 3 d,and subsequently treated with ASIV for additional 5 d.The EXOs from untreated NSCs and ASIV-pretreated NSCs(ASIV-EXOs)were isolated via ultracentrifugation of the cell supernatant.These EXOs were characterized using Western blot to detect specific markers such as CD63,tumor sus-ceptibility gene 101(TSG101)and calnexin.Nanoparticle analysis was employed to determine the size,and the morpholo-gy of the EXOs was observed under electron microscope.Six to eight-week-old SD male rats were randomly assigned to 6 groups:sham group,middle cerebral artery occlusion/reperfusion(MCAO/R)model group,edaravone(EDA)treatment(MCAO/R+EDA)group,EXOs treatement(MCAO/R+EXOs)group and ASIV-EXOs treatment(MCAO/R+ASIV-EXOs)group.Tail vein injections were administered within 2 h following the successful establishment of the MCAO/R model.The Zea Longa method was utilized to evaluate neurological deficits,while the TTC method was employed to assess brain infarc-tion.Pathological changes were examined through HE staining,and TUNEL and caspase-1 immunofluorescence double staining were conducted to detect cellular pyroptosis.Serum levels of interleukin-1β(IL-1β)and IL-18 were measured us-ing ELISA,and Western blot was performed to evaluate the expression of caspase-1,nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3),apoptosis-associated speck-like protein containing a caspase recruitment domain(ASC),gasdermin D(GSDMD),and IL-18 proteins in the ischemic area of the rat cerebral cortex across all groups.RE-SULTS:The MCAO/R group exhibited significantly higher neurological deficit scores compared to the sham group(P＜0.01)and lower scores in the administered groups relative to the MCAO/R group(P＜0.05).Cerebral infarction was mark-edly increased in the MCAO/R group compared to the sham group(P＜0.01),whereas the infarction area was reduced in the administered groups compared to the MCAO/R group(P＜0.05).Serum levels of IL-1β and IL-18 were significantly el-evated in the MCAO/R group versus the sham group(P＜0.01)and were lower in the administered groups compared to the MCAO/R group(P＜0.01).Moreover,IL-1β and IL-18 levels in the MCAO/R+ASIV-EXOs group were lower than those in the MCAO/R+EXOs group(P＜0.05).HE staining revealed pronounced sieve-like infarction foci in the ischemic area of the rat cerebral cortex in MCAO/R group,characterized by disorganized neuronal arrangements,reduced or absent Nys-trom's vesicles,shrunken or fragmented nuclei,and numerous red neurons.In contrast,drug-treated groups exhibited milder pathological changes with clearer neuronal structures and a significant reduction in red neuron counts.Immunofluo-rescence double staining indicated a significant increase in double-positive cells in the MCAO/R group compared to the sham group(P＜0.01),with a decrease in double-positive cells in the administered groups relative to the MCAO/R group(P＜0.05)and a further reduction in the MCAO/R+ASIV-EXOs group compared to the MCAO/R+EXOs group(P＜0.05).The expression levels of caspase-1,NLRP3,ASC,IL-18 and GSDMD proteins in the ischemic region of the rat cerebral cortex were significantly reduced in the administered groups compared to the MCAO/R group(P＜0.01),with further re-duction observed in the MCAO/R+ASIV-EXOs group compared to the MCAO/R+EXOs group(P＜0.05).CONCLU-SION:Exosomes derived from ASIV-pretreated NSCs attenuate brain damage in ischemic stroke rats,potentially through a mechanism involving the inhibition of pyroptosis mediated by the NLRP3/caspase-1 pathway.

Objective To study the correlation between the level of CaMKIV and essential hypertension (EH) in Shihezi community. Methods One hundred and forty-six patients with EH and 142 with normal blood pressure are enrolled from 15 communities in shihezi. We collected the clinical data, including blood pressure, body mass index, waist circumference, blood lipids. The serum level of CaMKIV was detected using an enzyme linked immunosorbent assay. Results The serum level of CaMKIV in the EH group was significantly lower than that in the normal blood pressure group (P < 0.05). The serum CaMKIV was negatively correlated with systolic BP and diastolic BP (r = -0.304, -0.452, all P < 0.05), with more obvious correlation with patients whose diastolic blood pressure was over 100 mmHg (r = -0.571, P < 0.05). Conclusions The serum level of CaMKIV is negatively correlated with EH, which is an independent factor of EH.