RiPerC Attenuates Cerebral Ischemia Injury through Regulation of miR-98/PIK3IP1/PI3K/AKT Signaling Pathway

Association of TAB2 gene polymorphism with endometrial cancer susceptibility and clinical analysis

Objective

Transforming growth factor-β-activated kinase 1 binding protein 2 (TAB2) plays a vital role in inflammatory pathways. It has also been considered a potential target for the enhancement of the the antiestrogen effects. Previous evidence has indicated that TAB2 gene variants are associated with several diseases, whereas their potential correlation with endometrial cancer (EC) is unclear. This study aims to initially explore the association between TAB2 gene polymorphisms (rs237028 /AG, rs521845 T/G, and rs652921 T/C) and EC.

Materials and Methods

Polymerase chain reaction-restriction fragment length polymorphism was applied to determine the genotype composition and the allele frequencies of TAB2 gene variant polymorphisms in 270 EC patients and 294 healthy controls.

Results

The G allele of rs521845 was related to the increase of EC risk [p=0.08, odds ratio (OR): 0.72, 95% confidence interval (CI): 0.56-0.91]. Moreover, EC risk was associated with rs521845 in different genetic models (p=0.017, OR: 0.63, 95% CI: 0.44-0.91 in the codominant model; p=0.0051, OR: 0.61, 95% CI: 0.43-0.87 in the dominant model). For rs237028, the percentage of AG genotype in patients with highly differentiated tumours (G1) was significantly higher than that in moderately, poorly differentiated patients (G2/G3) (p=0.031, OR: 0.77, 95% CI: 0.45-1.30).

Conclusion

Our results showed that the rs521845 polymorphism of TAB2, was associated with EC risk, suggesting that TAB2 may play a crucial role in EC prognosis.

PIK3IP1: structure, aberration, function, and regulation in diseases

Phosphoinositide 3-kinase (PI3K) pathway, controlling diverse functions in cells, is one of the most frequently dysregulated pathways in cancer. Several negative regulators have been reported to intricately constrain the overactivation of PI3K pathway. Phosphatidylinoinosidine-3-kinase interacting protein 1 (PIK3IP1), as a unique transmembrane protein, is a newly discovered negative regulator of PI3K pathway. PIK3IP1 negatively regulates PI3K activity by directly binding to the p110 catalytic subunit of PI3K. It has been reported that PIK3IP1 is frequently low expressed in tumors and autoimmune diseases. In tumor cells and impaired cardiomyocyte, PIK3IP1 inhibits cell proliferation and survival. Consistently, the expression of PIK3IP1 is related with the condition of cancer. In addition, PIK3IP1 inhibits the inflammatory response and immune function via maintaining the quiescent state of immune cells. Thus, low expression of PIK3IP1 represents the severe condition of autoimmune diseases. PIK3IP1 is regulated by transcription factors, epigenetic factors or micro-RNAs to facilitate its normal function in different cellular contexts. This review integrates the total findings on PIK3IP1 in different disease, and summaries the structure, biological functions and regulatory mechanisms of PIK3IP1.

Mxene-bpV plays a neuroprotective role in cerebral ischemia-reperfusion injury by activating the Akt and promoting the M2 microglial polarization signaling pathways

Studies have shown that the inhibition of phosphatase and tensin homolog deleted on chromosome 10 (PTEN)was neuroprotective against ischemia/reperfusion(I/R) injury. Bisperoxovanadium (bpV), a derivative of vanadate, is a well-established inhibitor of PTEN. However, its function islimited due to its general inadequacy in penetrating cell membranes. Mxene(Ti3C2Tx) is a novel two-dimensional lamellar nanomaterial with an excellent ability to penetrate the cell membrane. Yet, the effects of this nanomaterial on nervous system diseases have yet to be scrutinized. Here, Mxene(Ti3C2Tx) was used for the first time to carry bpV(HOpic), creating a new nanocomposite Mxene-bpV that was probed in a cerebral I/R injury model. The findings showed that this synthetic Mxene-bpV was adequately stable and can cross the cell membraneeasily. We observed that Mxene-bpV treatment significantly increased the survival rate of oxygen glucose deprivation/reperfusion(OGD/R)--insulted neurons, reduced infarct sizes and promoted the recovery of brain function after mice cerebral I/R injury. Crucially, Mxene-bpV treatment was more therapeutically efficient than bpV(HOpic) treatment alone over the same period. Mechanistically, Mxene-bpV inhibited the enzyme activity of PTEN in vitro and in vivo. It also promoted the expression of phospho-Akt (Ser473) by repressing PTEN and then activated the Akt pathway to boost cell survival. Additionally, in PTEN transgenic mice, Mxene-bpV suppressed I/R-induced inflammatory response by promoting M2 microglial polarization through PTEN inhibition. Collectively, the nanosynthetic Mxene-bpV inhibited PTEN' enzymatic activity by activating Akt pathway and promoting M2 microglial polarization, and finally exerted neuroprotection against cerebral I/R injury.

miR-96-5p alleviates cerebral ischemia-reperfusion injury in mice by inhibiting pyroptosis via downregulating caspase 1

Ischemic stroke is one of the leading causes of global mortality and disability. Nevertheless, successful treatment remains limited. In this study, we investigated the efficacy and the mechanism of miR-96-5p in protecting acute ischemic brain injury in adult mice. Focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) in adult male C57BL/6 mice. MiR-96-5p or the negative control was administered via intracerebroventricular injection. The expression of pyroptosis-related genes and activation of various resident cells in the brain was assessed by RT-qPCR, western blot, immunohistochemistry, and immunofluorescence. Modified neurological severity score, rotarod test, cylinder test, brain water content, and cerebral infarction volume were used to evaluate the behavioral deficits and the severity of brain injury after MCAO. Flow cytometry, TUNEL staining, and Nissl staining were employed to assess the neuron damage. MiR-96-5p decreased markedly in the ischemic stroke model in vivo and in vitro. MiR-96-5p mimics suppressed the expression of caspase 1 and alleviated the apoptosis rate in OGD/R treatment N2a cells, however, the miR-96-5p inhibitor caused the opposite results. Intracerebroventricular delivery of miR-96-5p agomir significantly mitigated behavioral deficits, brain water content, and cerebral infarction volume after MCAO. In addition, treatment with miR-96-5p agomir downregulated the expression of caspase 1/cleaved caspase 1 and Gsdmd/Gsdmd-N, while alleviating the neuron damage. In summary, overexpression of miR-96-5p suppresses pyroptosis and reduces brain damage in the acute phase of ischemic stroke, providing new insight into the treatment of acute ischemic stroke.

Salvianolic acids and its potential for cardio-protection against myocardial ischemic reperfusion injury in diabetes

The incidence of diabetes and related mortality rate increase yearly in modern cities. Additionally, elevated glucose levels can result in an increase of reactive oxygen species (ROS), ferroptosis, and the disruption of protective pathways in the heart. These factors collectively heighten the vulnerability of diabetic individuals to myocardial ischemia. Reperfusion therapies have been effectively used in clinical practice. There are limitations to the current clinical methods used to treat myocardial ischemia-reperfusion injury. As a result, reducing post-treatment ischemia/reperfusion injury remains a challenge. Therefore, efforts are underway to provide more efficient therapy. Salvia miltiorrhiza Bunge (Danshen) has been used for centuries in ancient China to treat cardiovascular diseases (CVD) with rare side effects. Salvianolic acid is a water-soluble phenolic compound with potent antioxidant properties and has the greatest hydrophilic property in Danshen. It has recently been discovered that salvianolic acids A (SAA) and B (SAB) are capable of inhibiting apoptosis by targeting the JNK/Akt pathway and the NF-κB pathway, respectively. This review delves into the most recent discoveries regarding the therapeutic and cardioprotective benefits of salvianolic acid for individuals with diabetes. Salvianolic acid shows great potential in myocardial protection in diabetes mellitus. A thorough understanding of the protective mechanism of salvianolic acid could expand its potential uses in developing medicines for treating diabetes mellitus related myocardial ischemia-reperfusion.

Effects of different remote ischemia perconditioning methods on cerebral infarct volume and neurological impairment in rats

Remote ischemic perconditioning (RIPerC) is a novel neuroprotective method against cerebral infarction that has shown efficacy in animal studies but has not been consistently neuroprotective in clinical trials. We focused on the temporal regulation of ischemia-reperfusion by RIPerC to establish an optimal method for RIPerC. Rats were assigned to four groups: 10 min ischemia, 5 min reperfusion; 10 min ischemia, 10 min reperfusion; 5 min ischemia, 10 min reperfusion; and no RIPerC. RIPerC interventions were performed during ischemic stroke, which was induced by a 60-min left middle cerebral artery occlusion. Infarct volume, sensorimotor function, neurological deficits, and cellular expressions of brain-derived neurotrophic factor (BDNF), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and caspase 3 were evaluated 48 h after the induction of ischemia. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) was also performed. RIPerC of 10 min ischemia/10 min reperfusion, and 5 min ischemia/10 min reperfusion decreased infarct volume, improved sensorimotor function, decreased Bax, caspase 3, and TUNEL-positive cells, and increased BDNF and Bcl-2 expressions. Our findings suggest RIPerC with a reperfusion time of approximately 10 min exerts its neuroprotective effects via an anti-apoptotic mechanism. This study provides important preliminary data to establish more effective RIPerC interventions.

MiR-140-3p directly targets Tyro3 to regulate OGD/R-induced neuronal injury through the PI3K/Akt pathway

BACKGROUND AND PURPOSE

MicroRNAs (miRNAs) are highly expressed in the central nervous system and play important roles in ischaemic stroke pathogenesis. However, the role of miRNAs in cerebral ischaemia-reperfusion injury remains unclear. Here, we investigated the role of miR-140-3p in regulating oxygen-glucose deprivation/reoxygenation (OGD/R)-induced neuronal injury in vitro to identify a new biomarker for research on ischaemic stroke.

METHODS

The differential expression of miR-140-3p and Tyro3 in OGD/R-exposed N2a cells was verified by qRT-PCR. N2a cells were transfected with miR-140-3p mimic, miR-140-3p inhibitor, Tyro3 or siTyro3, and qRT-PCR, Western blotting, the Cell counting kit-8 (CCK-8) assay, Hoechst 33342/PI staining and flow cytometry analyses were performed to measure miRNA, mRNA and protein expression; cell viability; and apoptosis.

RESULTS

OGD/R-exposed N2a cells exhibited increased miR-140-3p expression, decreased viability, reduced Bcl-2 protein expression and increased Bax and Caspase-3 protein expression and apoptosis; the miR-140-3p mimic markedly amplified these changes, exacerbating OGD/R-induced injury to N2a cells, while the miR-140-3p inhibitor reversed these changes and alleviated OGD/R-induced injury. OGD/R-exposed N2a cells expressed less Tyro3, and Tyro3 overexpression increased cell viability and Bcl-2 protein expression, reduced Bax and Caspase-3 protein expression, and alleviated OGD/R-induced injury. However, silencing Tyro3 reversed these changes and exacerbated OGD/R-induced injury. MiR-140-3p directly bound the Tyro3 mRNA 3'UTR. Rescue experiments indicated that the miR-140-3p mimic-induced changes in cell viability and protein expression were alleviated by Tyro3 overexpression and that the miR-140-3p inhibitor-induced changes in cell viability and protein expression were alleviated by silencing Tyro3. Tyro3 overexpression increased cell viability and PI3K and p-Akt protein expression, but these effects were weakened by the addition of LY294002.

CONCLUSIONS

MiR-140-3p directly targets Tyro3 to regulate cell viability and apoptosis of OGD/R-exposed N2a cells through the PI3K/Akt pathway, suggesting that miR-140-3p is a novel biomarker and therapeutic target for ischaemic stroke.

Characterization of 22q12 Microdeletions Causing Position Effect in Rare NF2 Patients with Complex Phenotypes

Neurofibromatosis type 2 is an autosomal dominant tumor-prone disorder mainly caused by NF2 point mutations or intragenic deletions. Few individuals with a complex phenotype and 22q12 microdeletions have been described. The 22q12 microdeletions’ pathogenic effects at the genetic and epigenetic levels are currently unknown. We here report on 22q12 microdeletions’ characterization in three NF2 patients with different phenotype complexities. A possible effect of the position was investigated by in silico analysis of 22q12 topologically associated domains (TADs) and regulatory elements, and by expression analysis of 12 genes flanking patients’ deletions. A 147 Kb microdeletion was identified in the patient with the mildest phenotype, while two large deletions of 561 Kb and 1.8 Mb were found in the other two patients, showing a more severe symptomatology. The last two patients displayed intellectual disability, possibly related to AP1B1 gene deletion. The microdeletions change from one to five TADs, and the 22q12 chromatin regulatory landscape, according to the altered expression levels of four deletion-flanking genes, including PIK3IP1, are likely associated with an early ischemic event occurring in the patient with the largest deletion. Our results suggest that the identification of the deletion extent can provide prognostic markers, predictive of NF2 phenotypes, and potential therapeutic targets, thus overall improving patient management.

Study on the Mechanism of Üstikuddus Sherbiti in Ischemic Cerebrovascular Diseases: Based on Network Pharmacology

This paper aims to study the potential biological mechanism of Üstikuddus Sherbiti (ÜS) in the treatment of ischemic cerebrovascular diseases (ICVD) by the network pharmacology method. Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was used to obtain effective constituents of ÜS by screening eligible oral utilization, drug similarity, and blood-brain barrier permeability threshold. By drug target prediction and stroke treatment target mining, 2 target data sets were analyzed to find intersection targets and the corresponding constituents were used as active constituents. An active constituent target network and an effective constituent target network were constructed by using Cytoscape 3.7.2 software. Degree parameters of the effective constituent target network were analyzed to find important effective constituents and targets. Through protein-protein interaction (PPI) analysis/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, potential signaling pathways of ÜS in ischemic stroke were found out. AutoDock was used for molecular docking verification. A total of 90 active constituents of ÜS were screened out. There were 10 active constituents against ICVD, including quercetin, luteolin, kaempferol, and naringenin, and 10 important targets for anticerebral ischemia, namely, PIK3CA, APP, PIK3R1, MAPK1, MAPK3, AKT1, PRKCD, Fyn, RAC1, and NF-κB1. Based on the protein interaction network, the important targets of ÜS were significantly enriched in PI3K-Akt signaling pathway, neuroactive ligand-receptor interaction pathway, Ras signaling pathway, etc. ÜS in ICVD has characteristics like multiple targets, multiple approaches, and multiple pathways. Results of molecular docking showed that the active components in ICVD had a good binding ability with the key targets. Its main biological mechanism may be related to the PI3K-Akt and Ras-MAPK centered signaling pathway. Our study demonstrated that ÜS exerted the effect of treating ICVD by regulating multiple targets and multiple channels with multiple components through the method of network pharmacology and molecular docking.

Knockdown of forkhead box protein P1 alleviates hypoxia reoxygenation injury in H9c2 cells through regulating Pik3ip1/Akt/eNOS and ROS/mPTP pathway

Forkhead box protein P1 (Foxp1) exerts an extensive array of physiological and pathophysiological impacts on the cardiovascular system. However, the exact function of myocardial Foxp1 in myocardial ischemic reperfusion injury (MIRI) stays largely vague. The hypoxia reoxygenation model of H9c2 cells (the rat ventricular myoblasts) closely mimics myocardial ischemia-reperfusion injury. This report intends to research the effects and mechanisms underlying Foxp1 on H9c2 cells in response to hypoxia (12 h)/reoxygenation (4 h) (HR) stimulation. Expressions of Foxp1 and Phosphatidylinositol 3-kinase interacting protein 1 (Pik3ip1) were both upregulated in ischemia/reperfusion (IR)/HR-induced injury. Stimulation through HR led to marked increases in cellular apoptosis, mitochondrial dysfunction, and superoxide generation in H9c2 cells, which were rescued with knockdown of Foxp1 by siRNA. Silence of Foxp1 depressed expression of Pik3ip1 directly activated the PI3K/Akt/eNOS pathway and promoted nitric oxide (NO) release. Moreover, the knockdown of Foxp1 blunted HR-induced enhancement of reactive oxygen species (ROS) generation, thus alleviating excessive persistence of mitochondrial permeability transition pore (mPTP) opening and decreased mitochondrial apoptosis-associated protein expressions in H9c2 cells. Meanwhile, these cardioprotective effects can be abolished by LY294002, NG-nitro-L-arginine methyl ester (L-NAME), and Atractyloside (ATR), respectively. In summary, our findings indicated that knockdown of Foxp1 prevented HR-induced encouragement of apoptosis and oxidative stress via PI3K/Akt/eNOS signaling activation by targeting Pik3ip1 and improved mitochondrial function by inhibiting ROS-mediated mPTP opening. Inhibition of Foxp1 may be a promising therapeutic avenue for MIRI.

Palmatine Protects against Cerebral Ischemia/Reperfusion Injury by Activation of the AMPK/Nrf2 Pathway

Palmatine (PAL), a natural isoquinoline alkaloid, possesses extensive biological and pharmaceutical activities, including antioxidative stress, anti-inflammatory, antitumor, neuroprotective, and gastroprotective activities. However, it is unknown whether PAL has a protective effect against ischemic stroke and cerebral ischemia/reperfusion (I/R) injury. In the present study, a transient middle cerebral artery occlusion (MCAO) mouse model was used to mimic ischemic stroke and cerebral I/R injury in mice. Our study demonstrated that PAL treatment ameliorated cerebral I/R injury by decreasing infarct volume, neurological scores, and brain water content. PAL administration attenuated oxidative stress, the inflammatory response, and neuronal apoptosis in mice after cerebral I/R injury. In addition, PAL treatment also decreases hypoxia and reperfusion- (H/R-) induced neuronal injury by reducing oxidative stress, the inflammatory response, and neuronal apoptosis. Moreover, the neuroprotective effects of PAL were associated with the activation of the AMP-activated protein kinase (AMPK)/nuclear factor E2-related factor 2 (Nrf2) pathway, and Nrf2 knockdown offsets PAL-mediated antioxidative stress and anti-inflammatory effects. Therefore, our results suggest that PAL may be a novel treatment strategy for ischemic stroke and cerebral I/R injury.