Electroacupuncture regulates histone acetylation of Bcl-2 and Caspase-3 genes to improve ischemic stroke injury.

Background: Imbalances between Bcl-2 and caspase-3 are significant evidence of apoptosis, which is considered an influential factor in rapidly occurring neuronal cell death and the decline of neurological function after stroke. Studies have shown that acupuncture can reduce poststroke brain cell damage via either an increase in Bcl-2 or a reduction in caspase-3 exposure. The current study aimed to investigate whether acupuncture could modulate Bcl-2 and caspase-3 expression through histone acetylation modifications, which could potentially serve as a neuroprotective mechanism. Methods: This study used TTC staining, Nissl staining, Clark neurological system score, and Evans Blue (EB) extravasation to evaluate neurological damage following stroke. The expression of Bcl-2/caspase-3 mRNA was detected by real-time fluorescence quantification of PCR (real-time PCR), whereas the protein expression levels of Bcl-2, Bax, caspase-3, and cleaved caspase-3 were assessed using western blotting. TUNEL staining of the ischemic cortical neurons determined apoptosis in the ischemic cortex. Histone acetyltransferase (HAT) and histone deacetylase (HDAC) activities, along with the protein performance of AceH3, H3K9ace, and H3K27ace, were detected to evaluate the degree of histone acetylation. The acetylation enrichment levels of H3K9 and K3K27 in the Bcl-2/caspase-3 gene were assessed using Chromatin Immunoprecipitation (ChIP) assay. Results: Our data demonstrated that electroacupuncture (EA) exerts a significant neuroprotective effect in middle cerebral artery occlusion (MCAO) rats, as evidenced by a reduction in infarct volume, neuronal damage, Blood-Brain Barrier (BBB) disruption, and decreased apoptosis of ischemic cortical neurons. EA treatment can promote the mRNA and protein expression of the Bcl-2 gene in the ischemic brain while reducing the mRNA and protein expression levels of caspase-3 and effectively decreasing the protein expression levels of Bax and cleaved caspase-3. More importantly, EA treatment enhanced the level of histone acetylation, including Ace-H3, H3K9ace, and H3K27ace, significantly enhanced the occupancy of H3K9ace/H3K27ace at the Bcl-2 promoter, and reduced the enrichment of H3K9ace and H3K27ace at the caspase-3 promoter. However, the Histone Acetyltransferase inhibitor (HATi) treatment reversed these effects. Conclusions: Our data demonstrated that EA mediated the expression levels of Bcl-2 and caspase-3 in MCAO rats by regulating the occupancy of acetylated H3K9/H3K27 at the promoters of these two genes, thus exerting a cerebral protective effect in ischemic reperfusion (I/R) injury.

Characteristics of Electroacupuncture Preconditioning and Treatment on Regulation of the Brain Transcriptome in Rats with Ischemic Stroke.

BACKGROUND: Accumulating evidence suggests that acupuncture may serve as a potent strategy to mitigate the deleterious effects of ischemic stroke on neural tissue. The present investigation delineated the neuroprotective potential of electroacupuncture (EA) administered pre-and post-stroke, with a focus on determining the commonalities and disparities between these two therapeutic approaches in ameliorating ischemic stroke-induced brain injury. The ultimate objective is to inform optimal timing for acupuncture intervention in the clinical management and prevention of stroke. METHODS: The extent of cerebral infarction was quantified with 2,3,5-triphenyltetrazolium chloride staining. The integrity of the blood-brain barrier was assessed by evaluating the extravasation of Evans blue (EB) dye, while neurological function was appraised using the Longa neurological scoring system. RNA sequencing was employed to examine the transcriptomic landscape of ischemic brain tissue, with subsequent bioinformatics annotation of the sequencing data facilitated by Metascape. RESULTS: (1) A notable decrease in the ischemic infarct volume was observed in both the EA-preconditioned plus middle cerebral artery occlusion (MCAO), EA-preconditioned plus middle cerebral artery occlusion (EAM) and MCAO plus EA-treated (MEA) groups, compared to the MCAO group. Furthermore, the decreased leakage of EB and reduction in neurological function impairment scores were evident in the EAM and MEA groups compared with the MCAO group. (2) Relative to the Sham group, the MCAO group exhibited a total of 4798 differentially expressed genes (DEGs), with 67.84% demonstrating an expression fold change (FC) greater than 1.5, and 34.16% exceeding a FC of 2. The EAM and MEA groups displayed 4020 and 1956 DEGs, respectively, compared to the MCAO group. In both groups, more than 55% of DEGs showed an expression FC surpassing 1.5, whereas only approximately 10% exhibited a change greater than 2-fold. Remarkably, EA preconditioning and EA treatment resulted in the reversal of 18.72% and 28.91% of DEGs, respectively, in the MCAO group. (3) The DEGs upregulated in response to ischemic stroke were predominantly implicated in immune inflammatory processes and cellular apoptosis, whereas the downregulated DEGs were associated with neurogenesis and neuronal signal transduction. The MEA-induced upregulated DEGs were primarily involved in neural transmission and metabolic processes, whereas the downregulated DEGs were linked to excessive inflammatory responses to physical and chemical stimuli, as well as cell matrix adhesion chemotaxis. In the context of EAM, the upregulated DEGs were chiefly related to protein biosynthesis, and energy and metabolic processes, whereas the downregulated genes were connected to gene transcriptional activity, synaptic function, and neuronal architecture. CONCLUSIONS: Both preconditioning and post-event treatment with acupuncture demonstrated efficacy in mitigating pathological damage to brain tissue in a rat model of ischemic stroke, albeit with some divergences in their gene targets. The integration of EA preconditioning and treatment may potentially confer enhanced neuroprotection in the clinical management of stroke patients.

Electro-acupuncture treatment inhibits the inflammatory response by regulating γδ T and Treg cells in ischemic stroke.

BACKGROUND: Electro-acupuncture (EA) is an effective and safe treatment for ischemic stroke. It is not only capable of reducing cerebral damage but also alleviating intestinal inflammation. However, its mechanism has not been fully elucidated. METHODS: All rats were randomly divided into three experimental groups: the SHAM group, the MCAO group, and the MEA (MCAO+EA) group. Ischemic-reperfusion (I/R) injury was induced by MCAO surgery. Rats in the MEA group were treated with EA stimulation in the "Baihui" acupoint (1 mA, 2/15 Hz, 20 min for each time). The Real-time (RT)-qPCR was used to evaluate the mRNA expression of inflammation factors in the ischemic brain and the small intestine after I/R injury. In addition, our research evaluated the effects of EA on regulatory T cells (Tregs) and γδ T cells in the small intestine and brain via Flow cytometry analysis. Finally, we applied CM-Dil and CFSE injection and explored the potential connections of T cells between the ischemic hemisphere and the small intestine. RESULTS: Our results suggested that EA treatment could significantly reduce the inflammation response in the ischemic brain and small intestine 3 days after I/R injury in rats. To be specific, EA increased the percentage of Tregs in the brain and the small intestine and decreased intestinal and cerebral γδ T cells. Concomitantly, after EA treatment, the percentage of cerebral CD3+TCRγδ+CFSE+ cells dropped from 12.06% to 6.52% compared with the MCAO group. CONCLUSIONS: These findings revealed that EA could regulate the Tregs and γδ T cells in the ischemic brain and the small intestine, which indicated its effect on inhibiting inflammation. And, EA could inhibit the mobilization of intestinal T cells, which may contribute to the protection of EA after ischemic stroke.

Electro-acupuncture treatment ameliorates intestinal inflammatory injury in cerebral ischemia-reperfusion rats via regulating the balance of Treg / γδ T cells.

Electro-acupuncture (EA) has an anti-inflammatory role in ischemic stroke, but whether the protective effect of EA involves the regulation of the intestine barrier and Treg/ γδ T cells is unclear. Cerebral ischemia-reperfusion (I/R) injury was induced by middle cerebral artery occlusion(MCAO) for 2 h followed by reperfusion for 24 h. The rats have treated with EA at the "Baihui" acupoint(GV20). Triphenyl tetrazolium chloride (TTC) staining and Longa neurologic score were performed to evaluate the outcomes after ischemic stroke. Inflammatory factor expression levels in the serum, ischemic hemisphere brain, and small intestine were detected by ELISA or RT-qPCR. Additionally, the morphology change of the small intestine was evaluated by analyzing villus height and smooth muscle thickness. Meanwhile, the expression of tight-junction proteins, including Zonula Occludens-1 (ZO-1), Occludin, and Claudin-1, were detected to evaluate the impact of EA on mucosal permeability in the small intestine. The percentages of regulatory T cells (Tregs) (CD45+CD4+Foxp3+) and γδ T cells (CD45+CD4-γδ T+) were measured to assess the effect of EA on intestinal T cells. EA decreased the brain infarction volume and intestine barrier injury in ischemic stroke rats. At the same time, it effectively suppressed the post-stroke inflammation in the brain and small intestine. More importantly, EA treatment increased the percentage of Tregs in the small intestine while reducing the rate of γδ T cells, and ultimately increased the ratio of Treg/ γδ T cells. These results demonstrated that EA ameliorated intestinal inflammation damage by regulating the Treg/ γδ T cell polarity shift and improving the intestine barrier integrity in rats with I/R injury. This may be one of the mechanisms underlying the anti-ischemic injury effects of acupuncture on stroke.

Gene expression profiling reveals an inflammatory process in the anx/anx mutant mice.

Anorexia (anx) is a recessive mutation that causes lethal starvation in homozygous mice. Studies of anx/anx mice hypothalamus have shown abnormalities in the orexigenic (NPY/AGRP neurons) and the anorexigenic (POMC/CART neurons) pathways. By gene expression profiling using cDNA and oligonucleotide microarrays, we have shown that a surexpression of genes involved in inflammatory process occurred in anx mice hypothalamus. This inflammatory process could be the cause of the anorexia phenotype observed in these mice.