Down-Regulation of Long Non-Coding RNA AK139328 Reduces Cell Inflammation and Apoptosis in Cerebral Ischemia Reperfusion Injury

Cerebral ischemia-reperfusion injury (CIRI) refers to the phenomenon that the ischemic injury of brain leads to the injury of brain cells, and ischemic injury is further aggravated after the recovery of blood reperfusion. In this study, we first constructed Oxygen and glucose deprivation/reoxygenation (OGD/R) injury model of PC12 cells, we found that the expression of LncRNA AK139328 in model cells was significantly increased through RT-qPCR. Subsequently, we interfered LncRNA AK139328 in model cells by plasmid transfection and found that interfering LncRNA AK139328 could significantly reduce the expression of inflammatory factors, including TNF a, IL-1β, IL-6, McP-1, and oxidative stress-related factors, including ROS, MDA, LDH, while the expressions of SOD and GSHPx were significantly increased. Flow cytometry was used to detect cell apoptosis, and apoptosisrelated proteins bcl-2, Bax, cleaved-caspase3 and cleaved PARP-1 were detected by western blot. Results show that interfering LncRNA AK139328 could reduce the apoptosis rate of OGD/R cells and the expression of Bax, cleaved caspase3 and cleaved PARP-1, while increasing the expression of bcl-2. Meanwhile, we found that after interfering LncRNA AK139328, the expressions of Nrf2, HO-1, NQO-1 and phosphorylated-P65 increased, while P65 showed no significant changes. This may be related to Nrf2/HO-1 and NF-κB signaling pathways. In a word, our study showed that interfering with LncRNA AK139328 can reduce cell inflammation and apoptosis in CIRI.

Sufentanil alleviates cerebral ischemia-reperfusion injury by inhibiting inflammation and protecting the blood-brain barrier in rats

Stroke is a brain system disease with a high fatality rate and disability rate. About 80% of strokes are ischemic strokes. Cerebral ischemia-reperfusion injury (CIRI) caused by ischemic stroke seriously affects the prognosis of stroke patients. The purpose of this study is to investigate the effect of sufentanil (SUF) on CIRI model rats. We used middle cerebral artery occlusion (MCAO) to make the CIRI model in rats and monitored region cerebral blood flow (rCBF) to ensure that blood flow was blocked and recanalized. We used ELISA and RT-PCR to detect the expression of inflammatory factors in rat serum and brain tissue. In addition, we detected the expression of metalloproteinase (MMP) 2, MMP9 and collagen IV in brain tissues and performed Evans blue (EB) assay to determine the permeability of the blood-brain barrier (BBB). Finally, we clarified the apoptosis of brain tissue through the TUNEL staining and the detection of caspase3, Bcl2 and Bax. Various concentrations of SUF, especially 5, 10 and 25 μg/kg of SUF, all alleviated the infarct size, neurological function and brain edema of MCAO rats. SUF pretreatment also effectively reduced the expression of inflammatory cytokines in MCAO rats, including interleukin (IL)-1β, IL-4, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF)-α. In addition, SUF also inhibited MMP2 and MMP9 and promoted the expression of collagen IV, indicating that SUF attenuated the destruction of the BBB. SUF also inhibited caspase3 and Bax rats and promoted Bcl2 in MCAO rats, thus inhibiting cell apoptosis. SUF pretreatment effectively improved the neurological function and cerebral infarction of MCAO rats, inhibited excessive inflammation in rats, protected the BBB, and inhibited cell apoptosis in brain tissue.

Celastrol Protects against Cerebral Ischemia/Reperfusion Injury in Mice by Inhibiting Glycolysis through Targeting HIF-1α/PDK1 Axis

Cerebral ischemia/reperfusion (I/R) injury is closely related to dysfunctional glucose metabolism. Celastrol is a bioactive compound that has been found to exhibit neuroprotective effects in cerebral ischemia, while whether it can protect against cerebral I/R injury by regulating glycolysis remains unclear. The goal of this study is to investigate the role of celastrol on cerebral I/R injury and its underlying mechanisms in transient middle cerebral artery occlusion (tMCAO) mice. Methods. To observe the protective effect of celastrol and select its optimal dosage for further study, neurological score, TTC staining, and HE staining were used to evaluate neurological function, cerebral infarct volume, and cortical cell damage, respectively. QRT-PCR and Western blot were used to detect the mRNA and protein expression of hypoxia inducible factor-1α (HIF-1α), pyruvate dehydrogenasekinase1 (PDK1), lactate dehydrogenase A (LDHA), glucose transporter1 (GLUT1), and hexokinase2 (HK2), respectively. The lactate production, ATP level, and glucose content were assessed by assay kits. Results. Our results indicated that celastrol dose-dependently improved neurological function and reduced cerebral infarct volume and cortical cell death of tMCAO mice, and its optimal dosage was 4.5 mg/kg. In addition, celastrol significantly blocked I/R-induced increase of LDHA, GLUT1, HK2, and lactate production as well as decrease of ATP level and glucose content. Moreover, celastrol inhibited the I/R-induced upregulation of HIF-1α and PDK1. Overexpression of HIF-1α by DMOG reversed the protective effect of celastrol on cerebral I/R injury and blocked celastrol-induced suppression of glycolysis. Conclusions. Taken together, these results suggested that celastrol protected against cerebral I/R injury through inhibiting glycolysis via the HIF-1α/PDK1 axis.

Targeted Delivery of Intranasally Administered Cyclovirobuxine D Liposomes to Brain for Treatment Cerebral Ischemia-Reperfusion Injury via Anti-oxidative Stress and Activating Autophagy

The lack of effective therapy mandates development of treatment for cerebral ischemia-reperfusion injury (CIRI. The previous study suggested that Cyclovirobuxine D (CVBD) encapsulated in Angiopep-conjugated Polysorbate 80-Coated Liposomes showed a better brain targeting by intranasal administration. Therefore, this study focused on the protection and mechanism of CVBD brain-targeted liposomes in treating CIRI. In order to evaluate these, the CIRI rat model was induced by middle cerebral artery occlusion (MCAO)-reperfusion. Pharmacological evaluation was assessed in vivo by general indexs, neurobehavioral scores, triphenyl tetrazolium chloride (TTC) staining, histopathological staining (HE staining and Nissl staining), small animal magnetic resonance imaging, biochemical assay and Western blot. The results show that CVBD liposomes alleviated pathological damage of brain. Futhermore, the protective effect of CVBD liposomes on OGD/R-injured HT22 cell was investigated by cell fusion degree, cell proliferation curve and cell viability. OGD/R-injured HT22 cell was infected by mRFP-GFP-LC3 adenovirus. The autophagosome and autophagy flow were observed by laser confocal microscopy, and autophagy-related protein expressions (LC3, p62 and Beclin 1) were analyzed by Western blot. Meanwhile, the classic autophagy inhibitor, chloroquine, was used to explore the autophagy-regulated mechanism of CVBD brain-targeted liposomes in treating CIRI. In cell model of oxygen and glucose deprivation/re-oxygenation, CVBD liposomes increased cell viability and decreased ROS level. CVBD liposomes improved oxidative stress protein expressions and activated autophagy in vitro. Furthermore, CVBD liposomes reversed the decrease of cell viability, increase of ROS level, and reduction of protein expressions associated to anti-oxidative stress and autophagy induced by chloroquine. Collectively, CVBD liposomes inhibited CIRI via regulating oxidative stress and enhancing autophagy level in vivo and in vitro, showing a great potential in treating CIRI in clinic.