Mechanism of acupuncture in attenuating cerebral ischaemia-reperfusion injury based on nuclear receptor coactivator 4 mediated ferritinophagy.

OBJECTIVE: To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury (CIRI) and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4 (NCOA4) mediated ferritinophagy. METHODS: Sprague-Dawley male rats were divided into four groups: the sham group, model group, acupuncture group, and sham acupuncture group. After 2 h of middle cerebral artery occlusion (MCAO), reperfusion was performed for 24 h to induce CIRI. The rats were treated with acupuncture at the Neiguan (PC6) and Shuigou (GV26) acupoints. Their neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after reperfusion. Triphenyltetrazolium chloride staining was applied to assess the cerebral infarct volume at 24 h after reperfusion. The malondialdehyde (MDA) and ferrous iron (Fe2+) levels were observed after 24 h of reperfusion using an assay kit. Western blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1 (FTH1) at 24 h after reperfusion. Moreover, the colocalization of ferritin with neurons, NCOA4 with microtubule-associated protein 1 light chain 3 (LC3), and NCOA4 with ferritin was visualized using immunofluorescence staining. RESULTS: Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture group. Following CIRI, the expression of NCOA4, LC3 and FTH1 was increased, which enhanced ferritinophagy and induced an inappropriate accumulation of Fe2+ and MDA in the ischaemic brain. However, acupuncture dramatically downregulated the expression of NCOA4, LC3 and FTH1, inhibited the overactivation of ferritinophagy, and decreased the levels of MDA and Fe2+. CONCLUSIONS: Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.

Effect of high-dose vitamin C on renal ischemia-reperfusion injury.

Acute kidney injury frequently occurs after cardiac surgery, and is primarily attributed to renal ischemia-reperfusion (I/R) injury and inflammation from surgery and cardiopulmonary bypass. Vitamin C, an antioxidant that is often depleted in critically ill patients, could potentially mitigate I/R-induced oxidative stress at high doses. We investigated the effectiveness of high-dose vitamin C in preventing I/R-induced renal injury. The ideal time and optimal dosage for administration were determined in a two-phase experiment on Sprague-Dawley rats. The rats were assigned to four groups: sham, IRC (I/R + saline), and pre- and post-vitC (vitamin C before and after I/R, respectively), with vitamin C administered at 200 mg/kg. Additional groups were examined for dose modification based on the optimal timing determined: V100, V200, and V300 (100, 200, and 300 mg/kg, respectively). Renal I/R was achieved through 45 min of ischemia followed by 24 h of reperfusion. Vitamin C administration during reperfusion significantly reduced renal dysfunction and tubular damage, more than pre-ischemic administration. Doses of 100 and 200 mg/kg during reperfusion reduced oxidative stress markers, including myeloperoxidase and inflammatory responses by decreasing high mobility group box 1 release and nucleotide-binding and oligomerization domain-like receptor 3 inflammasome. Overall beneficial effect was most prominent with 200 mg/kg. The 300 mg/kg dose, however, showed no additional benefits over the IRC group regarding serum blood urea nitrogen and creatinine levels and histological evaluation. During reperfusion, high-dose vitamin C administration (200 mg/kg) significantly decreased renal I/R injury by effectively attenuating the major triggers of oxidative stress and inflammation.

Moxibustion preconditioning reduces inflammatory response in rats with cerebral ischemia-reperfusion injury by regulating PI3K / AKT / mTOR signaling pathway. / 艾灸预处理通过调控PI3K/AKT/mTORä¿¡å·é€šè·¯å‡è½»è„‘ç¼ºè¡€å†çŒæ³¨æŸä¼¤å¤§é¼ ç‚Žæ€§ååº”.

OBJECTIVES: To observe the effect of moxibustion preconditioning on inflammatory response in rats with cerebral ischemia reperfusion injury (CIRI), so as to explore its mechanisms underlying improving CIRI. METHODS: Seventy-five male SD rats were randomly divided into sham operation, model, moxibustion preconditioning 3 days (Moxi 1), moxibustion preconditioning 5 days (Moxi 2) and moxibustion preconditioning 7 days (Moxi 3) groups, with 15 rats in each group. Moxibustion was applied at "Baihui"(GV20), "Dazhui"(GV14) and "Zusanli"(ST36) for 20 min once a day, totally for 3, 5 or 7 days. Thirty minutes after the last moxibustion treatment, the CIRI model was established by occlusion of the middle cerebral artery. The neurological deficit score was assessed by using Longa's method. The infarct size of the brain assessed after staining with 2% triphenyltetrazolium chloride (TTC). The morphological changes of cortical neurons were observed by HE staining. The contents of inflammatory factors interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), S-100ß protein (S-100ß) and neuron-specific enolase (NSE) were detected by ELISA. The expression of phosphatidylinositol-3-kinase (PI3K), p-PI3K, protein kinase B (AKT) and mammalian target of rapamycin (mTOR) proteins in the ischemic cortex tissues were detected by immunohistochemistry and Western blot. RESULTS: Compared with the sham operation group, the neurological function score and the percentage of cerebral ischemic volume were increased (P<0.01). The contents of serum IL-1ß, TNF-α, S-100ß and NSE were significantly increased (P<0.01), while the protein expressions of PI3K, p-PI3K, AKT and mTOR in the cerebral cortex were significantly decreased (P<0.01) in the model group. Compared with the model group, the neurological function score and the percentage of cerebral ischemic volume were significantly decreased (P<0.01). The contents of serum IL-1ß, TNF-α, S-100ß and NSE were significantly decreased (P<0.01), and the expressions of PI3K, p-PI3K, AKT and mTOR proteins in the cerebral cortex were significantly increased (P<0.01) in three moxibustion groups. Compared with the Moxi 1 and Moxi 2 groups, the above indicators were significantly improved in rats of the Moxi 3 group (P<0.01, P<0.05). CONCLUSIONS: Moxibustion preconditioning can significantly improve the neurological function of rats after ischemia-reperfusion, inhibit serum inflammatory factors IL-1 ß and TNF-α, inhibit brain tissue injury markers S-100ß and NSE, which may be related to the activation of PI3K/AKT/mTOR signaling pathway. The protective effect of moxibustion preconditioning for 7 days on CIRI was better than that of 5 days and 3 days.

Progress of researches on mechanisms of acupuncture underlying improvement of cerebral ischemia-reperfusion injury by regulating calcium overload. / é’ˆåˆºè°ƒæŽ§è„‘ç¼ºè¡€å†çŒæ³¨æŸä¼¤åŽé’™è¶ è½½æœºåˆ¶ç ”ç©¶è¿›å±•.

Ischemic stroke is currently the most common type of stroke, and the key pathological link is cerebral ischemia-reperfusion injury (CIRI), while the key factor leading to apoptosis and necrosis of ischemic nerve cells is calcium overload. Current studies have confirmed that acupuncture therapy has a good modulating effect on calcium homeostasis and can reduce cerebral ischemia-reperfusion induced damage of neuronal cells by inhibiting calcium overload. After reviewing the relevant literature published in the past 15 years, we find that acupuncture plays a role in regulating the pathological mechanism of calcium overload after CIRI by inhibiting the opening of connexin 43 hemichannels, regulating the intracellular free calcium ion concentration, suppressing the expression of calmodulin, and blocking the function of L-type voltage-gated calcium channels, thereby inhibiting calcium overload, regulating calcium homeostasis and antagonizing neuronal damage resulted from cerebral ischemia-reperfusion, which may provide ideas for future research.

Effects of Extracellular Calcium Concentration on Hepatic Ischemia-Reperfusion Injury in a Rat Model.

OBJECTIVES: Hypocalcemia is frequently identified during liver transplant. However, supplementation of extracellular calcium could induce increased intracellular calcium concentration, as a potential factor for injury to the liver graft. We evaluated the effects of regulating extracellular calcium concentrations on hepatic ischemia-reperfusion injury. MATERIALS AND METHODS: We randomly divided 24 Sprague-Dawley rats into 3 groups: group C received normal saline (n = 8), group L received citrate to induce hypocalcemia (n = 8), and group L-Co received citrate followed by calcium gluconate to ameliorate hypocalcemia (n = 8). Liver enzyme levels and extracellular calcium were measured before surgery, 1 hour after ischemia, and 2 hours after reperfusion. The primary outcome was liver enzyme levels measured 2 hours after reperfusion. In addition, we evaluated intracellular calcium levels, lactate dehydrogenase activity, and histopathological results in liver tissue. RESULTS: Three groups demonstrated significant differences in extracellular calcium concentrations, but intracellular calcium concentrations in liver tissue were not significantly different. Group L showed significantly lower mean arterial pressure than other groups at 1 hour after ischemia (93.6 ± 20.8 vs 69.4 ± 14.2 vs 86.6 ± 10.4 mmHg; P = .02, for group C vs L vs L-Co, respectively). At 2 hours after reperfusion, group L showed significantly higher liver enzymes than other groups (aspartate aminotransferase 443.0 ± 353.2 vs 952.3 ± 94.8 vs 502.4 ± 327.3 U/L, P = .01; and alanine aminotransferase 407.9 ± 406.5 vs 860.6 ± 210.9 vs 333.9 ± 304.2 U/L, P = .02; for group C vs L vs L-Co, respectively). However, no significant difference was shown in lactate dehydrogenase and histological liver injury grade. CONCLUSIONS: Administering calcium to rats with hypocalcemia did not increase intracellular calcium accumulation but instead resulted in less hepatic injury compared with rats with low extracellular calcium concentrations in this rat model study.

FDA compound library screening Baicalin upregulates TREM2 for the treatment of cerebral ischemia-reperfusion injury.

Acute ischemic stroke (AIS) is a leading cause of global incidence and mortality rates. Oxidative stress and inflammation are key factors in the pathogenesis of AIS neuroinjury. Therefore, it is necessary to develop drugs that target neuroinflammation and oxidative stress in AIS. The Triggering Receptor Expressed on Myeloid Cells 2 (TREM2), primarily expressed on microglial cell membranes, plays a critical role in reducing inflammation and oxidative stress in AIS. In this study, we employed a high-throughput screening (HTS) strategy to evaluate 2625 compounds from the (Food and Drug Administration) FDA library in vitro to identify compounds that upregulate the TREM2 receptor on microglia. Through this screening, we identified Baicalin as a potential drug for AIS treatment. Baicalin, a flavonoid compound extracted and isolated from the root of Scutellaria baicalensis, demonstrated promising results. Next, we established an in vivo mouse model of cerebral ischemia-reperfusion injury (MCAO/R) and an in vitro microglia cell of oxygen-glucose deprivation reperfusion (OGD/R) to investigate the role of Baicalin in inflammation injury, oxidative stress, and neuronal apoptosis. Our results showed that baicalin effectively inhibited microglia activation, reactive oxygen species (ROS) production, and inflammatory responses in vitro. Additionally, baicalin suppressed neuronal cell apoptosis. In the in vivo experiments, baicalin not only improved neurological functional deficits and reduced infarct volume but also inhibited microglia activation and inflammatory responses. Overall, our findings demonstrate the efficacy of Baicalin in treating MCAO/R by upregulating TREM2 to reduce inflammatory responses and inhibit neuronal apoptosis.

Effect of hyperbaric oxygen treatment on ischaemia-reperfusion injury in rats detorsioned after experimental ovarian torsion.

Introduction: This study aimed to investigate whether hyperbaric oxygen treatment (HBOT) could ameliorate ischaemia-reperfusion injury in a rat model of ovarian torsion-detorsion. Methods: Twenty-seven rats were divided among four groups: surgical sham rats (S) (n = 6) underwent identical anaesthesia and surgical incisions to other groups (n = 7 per group) but with no ovary intervention; torsion rats (T) underwent laparotomy, ovarian torsion, relaparotomy and sacrifice after three hours; torsion and detorsion rats (T/DT) underwent laparotomy, ovarian torsion (three hours), relaparotomy and detorsion, and sacrifice after one week; torsion, detorsion, hyperbaric oxygen rats (T/DT/HBOT) underwent laparotomy, ovarian torsion, relaparotomy and detorsion, and sacrifice after one week during which HBOT was provided 21 times (100% oxygen at 600 kPa for 50 min). In all groups blood collection for markers of oxidative stress or related responses, and ovary collection for histology were performed after sacrifice. Results: When the T/DT, and T/DT/HBOT groups were compared, 8-hydroxy-2'-deoxyguanosine (a marker of oxidative damage to DNA) and malondialdehyde (a product of lipid peroxidation) levels were lower in the T/DT/HBOT group. Anti-Mullerian hormone levels were higher in the T/DT/HBOT group compared to the T/DT group. In addition, oedema, vascular occlusion, neutrophilic infiltration and follicular cell damage were less in the T/DT/HBOT group than in the T/DT group. Conclusions: When biochemical and histopathological findings were evaluated together, HBOT appeared reduce ovarian ischaemia / reperfusion injury in this rat model of ovarian torsion-detorsion.

Cathodal bilateral transcranial direct-current stimulation regulates selenium to confer neuroprotection after rat cerebral ischaemia-reperfusion injury.

Non-invasive transcranial direct-current stimulation (tDCS) is a safe ischaemic stroke therapy. Cathodal bilateral tDCS (BtDCS) is a modified tDCS approach established by us recently. Because selenium (Se) plays a crucial role in cerebral ischaemic injury, we investigated whether cathodal BtDCS conferred neuroprotection via regulating Se-dependent signalling in rat cerebral ischaemia-reperfusion (I/R) injury. We first showed that the levels of Se and its transport protein selenoprotein P (SEPP1) were reduced in the rat cortical penumbra following I/R, whereas cathodal BtDCS prevented the reduction of Se and SEPP1. Interestingly, direct-current stimulation (DCS) increased SEPP1 level in cultured astrocytes subjected to oxygen-glucose deprivation reoxygenation (OGD/R) but had no effect on SEPP1 level in OGD/R-insulted neurons, indicating that DCS may increase Se in ischaemic neurons by enhancing the synthesis and secretion of SEPP1 in astrocytes. We then revealed that DCS reduced the number of injured mitochondria in OGD/R-insulted neurons cocultured with astrocytes. DCS and BtDCS prevented the reduction of the mitochondrial quality-control signalling, vesicle-associated membrane protein 2 (VAMP2) and syntaxin-4 (STX4), in OGD/R-insulted neurons cocultured with astrocytes and the ischaemic brain respectively. Under the same experimental conditions, downregulation of SEPP1 blocked DCS- and BtDCS-induced upregulation of VAMP2 and STX4. Finally, we demonstrated that cathodal BtDCS increased Se to reduce infract volume following I/R. Together, the present study uncovered a molecular mechanism by which cathodal BtDCS confers neuroprotection through increasing SEPP1 in astrocytes and subsequent upregulation of SEPP1/VAMP2/STX4 signalling in ischaemic neurons after rat cerebral I/R injury. KEY POINTS: Cathodal bilateral transcranial direct-current stimulation (BtDCS) prevents the reduction of selenium (Se) and selenoprotein P in the ischaemic penumbra. Se plays a crucial role in cerebral ischaemia injury. Direct-current stimulation reduces mitochondria injury and blocks the reduction of vesicle-associated membrane protein 2 (VAMP2) and syntaxin-4 (STX4) in oxygen-glucose deprivation reoxygenation-insulted neurons following coculturing with astrocytes. Cathodal BtDCS regulates Se/VAMP2/STX4 signalling to confer neuroprotection after ischaemia.

Effect of electroacupuncture on global cerebral ischemia-reperfusion injury in rats: A urine proteome analysis.

BACKGROUND: This study aimed to investigate dynamic urinary proteome changes of electroacupuncture (EP) on cerebral ischemia-reperfusion (CI/R) injured rats and to explore the therapeutic biological mechanisms of EP. METHODS: First, changed urinary proteins were found in EP stimulation in healthy rats. Then, we used a CI/R injury rat model induced by Pulsinelli's four-vessel occlusion (4-VO) method to explore the function of EP on urinary proteome in CI/R injury. Urine samples were collected for proteome analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatics analysis. RESULTS: In total, 384 proteins were identified, among which 47 proteins (23 upregulated, 24 downregulated) were differentially expressed with 0.6-log FC and p < .05. Gene ontology analysis revealed that the cell redox homeostasis, acute-phase response, response to lipopolysaccharide, and cellular response to glucocorticoid stimulus were significantly enriched. The partially biologically connected differential proteins were found by the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis in the EP group. With the CI/R rat model, 80 proteins (27 upregulated, 53 downregulated) were significantly changed in the CI/R rats compared to the controls. Among these differentially expressed proteins (DEPs), 23 proteins (17 upregulated, six downregulated) showed significant changes after EP treatment (0.6-log FC change, p < .05). The main related biological processes were aging, immune response, acute-phase response, liver regeneration, protein catabolic process, and response to oxidative stress. Many metabolic pathways were enriched by KEGG analysis. CONCLUSION: Our results indicate that the EP could alleviate cerebral damage induced by ischemia-reperfusion through an anti-inflammatory and metabolism regulation mechanism. The urinary proteome might reflect the pathophysiological changes in EP pretreatment in the treatment and prevention of CI/R injury.

Berberine Alleviates Ischemic Brain Injury by Enhancing Autophagic Flux via Facilitation of TFEB Nuclear Translocation.

Berberine has been demonstrated to alleviate cerebral ischemia/reperfusion injury, but its neuroprotective mechanism has yet to be understood. Studies have indicated that ischemic neuronal damage was frequently driven by autophagic/lysosomal dysfunction, which could be restored by boosting transcription factor EB (TFEB) nuclear translocation. Therefore, this study investigated the pharmacological effects of berberine on TFEB-regulated autophagic/lysosomal signaling in neurons after cerebral stroke. A rat model of ischemic stroke and a neuronal ischemia model in HT22 cells were prepared using middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation (OGD), respectively. Berberine was pre-administered at a dose of 100[Formula: see text]mg/kg/d for three days in rats and 90[Formula: see text][Formula: see text]M in HT22 neurons for 12[Formula: see text]h. 24[Formula: see text]h after MCAO and 2[Formula: see text]h after OGD, the penumbral tissues and OGD neurons were obtained to detect nuclear and cytoplasmic TFEB, and the key proteins in the autophagic/lysosomal pathway were examined using western blot and immunofluorescence, respectively. Meanwhile, neuron survival, infarct volume, and neurological deficits were assessed to evaluate the therapeutic efficacy. The results showed that berberine prominently facilitated TFEB nuclear translocation, as indicated by increased nuclear expression in penumbral neurons as well as in OGD HT22 cells. Consequently, both autophagic activity and lysosomal capacity were simultaneously augmented to alleviate the ischemic injury. However, berberine-conferred neuroprotection could be greatly counteracted by lysosomal inhibitor Bafilomycin A1 (Baf-A1). Meanwhile, autophagy inhibitor 3-Methyladenine (3-MA) also slightly neutralized the pharmacological effect of berberine on ameliorating autophagic/lysosomal dysfunction. Our study suggests that berberine-induced neuroprotection against ischemic stroke is elicited by enhancing autophagic flux via facilitation of TFEB nuclear translocation in neurons.

Chemical proteomics unveils that seventy flavors pearl pill ameliorates ischemic stroke by regulating oxidative phosphorylation.

Ischemic stroke has high mortality and morbidity rates and is the second leading cause of death in the world, but there is no definitive medicine. Seventy Flavors Pearl Pill (SFPP) is a classic formula in Tibetan Medicine. Clinical practice has shown the attenuation effect of SFPP on blood pressure disorders, strokes and their sequelae and other neurological symptoms, but its mechanism remains to be elucidated. In this study, we established three animal models in vivo and three cell models to evaluate the anti-hypoxia, anti-ischemia, and reperfusion injury prevention effects of SFPP. Quantitative proteomics revealed that oxidative phosphorylation (OXPHOS) is essential for SFPP's efficacy. Then, cysteine-activity based protein profiling technology, which reflects redox stress at the proteome level, was employed to illustrate that SFPP brought functional differences of critical proteins in OXPHOS. In addition, quantitative metabolomics revealed that SFPP affects whole energy metabolism with OXPHOS as the core. Finally, we performed a compositional identification of SFPP to initially explore the components of potential interventions in OXPHOS. These results provide new perspectives and tools to explore the mechanism of herbal medicine. The study suggests that OXPHOS could be a potential target for further research and intervention of ischemic stroke treatment.

Network pharmacology and experimental validation to investigate the mechanism of Nao-Ling-Su capsule in the treatment of ischemia/reperfusion-induced acute kidney injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Nao-Ling-Su Capsule (NLSC) is a traditional prescription, which is composed of fifteen herbs such as epimedium, Polygala tenuifolia, and Schisandra chinensis. It has the effect of strengthening the brain, calming nerves, and protecting the kidney, which has been used clinically for many years to strengthen the brain and kidney. However, the effect of NLSC in the treatment of acute kidney injury (AKI) is still unclear. AIM OF THE STUDY: The present study aims to elucidate the pharmacological actions of NLSC in the treatment of AKI. MATERIALS AND METHODS: Molecular targets for NLSC and AKI were obtained from various databases, and then we built networks of interactions between proteins (PPI) by employing string databases. Additionally, we employed the DAVID database to conduct gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Molecular docking was conducted to analyze the interaction between core components and their corresponding core targets. Next, the C57BL male mice model of ischemia/reperfusion damage (IRI) was developed, and the nephridial protective effect of NLSC was evaluated. The accuracy of the expected targets was confirmed using real-time quantitative polymerase chain reaction (RT-qPCR). The renal protective effect of NLSC was assessed using an immortalized human kidney tubular (HK-2) cell culture produced by oxygen-glucose deprivation (OGD). RESULTS: Network pharmacology analysis identified 199 common targets from NLSC and AKI. STAT3, HSP90AA1, TP53, MAPK3, JUN, JAK2, and VEGFA could serve as potential drug targets and were associated with JAK2/STAT3 signaling pathway, PI3K-Akt signaling pathway, etc. The molecular docking analysis confirmed significant docking activity between the main bioactive components and core targets, including STAT3 and KIM-1. Moreover, the AKI mice model was successfully established and NLSC pretreatment could improve renal function and alleviate renal damage. NLSC could alleviate renal inflammation and tubular cell apoptosis, and decrease the expression of STAT3 and KIM-1 in AKI mice. In vitro, both NLSC and drug-containing serum may protect HK-2 cells by inhibiting STAT3 signaling, especially STAT3-mediated apoptosis and KIM-1 expression. CONCLUSION: NLSC could alleviate renal inflammation and apoptosis, exerting its beneficial effects by targeting the STAT3/KIM-1 pathway. NLSC is a promising candidate for AKI treatment and provides a new idea and method for the treatment of AKI.

Investigation of neuroprotective and therapeutic effects of cannabidiol in an acute coronary syndrome model.

PURPOSE: The ischemia-reperfusion (I/R) injury seen in the heart can cause severe damage to essential organs such as the brain. Cannabidiol (CBD) obtained from Cannabis sativa is used today to treat various diseases. This study aimed to demonstrate CBD's neuroprotective and therapeutic properties in rats with brain damage caused by I/R in the heart. MATERIALS: Rats were divided into four groups; sham, I/R, I/R + Prophylactic CBD, and I/R + Therapeutic CBD. End of the experiment, brain tissues were collected for biochemical, histopathological, and genetic examinations. RESULTS: I/R damage increased the number of degenerative neurons, caspase-3 and TNF-α immunoexpression, total oxidant status levels, and oxidative stress index. Both prophylactic and therapeutic CBD administration reduced these increased values. In addition, the relative fold changes of AMPK, PGC-1α, SIRT1, and Bcl 2 decreased in the I/R group, and the relative fold change of Bax increased, which are indicators of ER stress and apoptosis. Both administrations of CBD reversed these genes' relative fold changes. CONCLUSION: CBD can be protective against brain injury caused by cardiac I/R damage through antioxidant, anti-inflammatory, and anti-apoptotic mechanisms.

Neuroprotection of rhubarb extract against cerebral ischaemia-reperfusion injury via the gut-brain axis pathway.

BACKGROUND: The gut-brain axis (GBA) plays a central role in cerebral ischaemia-reperfusion injury (CIRI). Rhubarb, known for its purgative properties, has demonstrated protective effects against CIRI. However, it remains unclear whether this protective effect is achieved through the regulation of the GBA. AIM: This study aims to investigate the mechanism by which rhubarb extract improves CIRI by modulating the GBA pathway. METHODS: We identified the active components of rhubarb extract using LC-MS/MS. The model of middle cerebral artery occlusion (MCAO) was established to evaluate the effect of rhubarb extract. We conducted 16S rDNA sequencing and untargeted metabolomics to analyze intestinal contents. Additionally, we employed HE staining, TUNEL staining, western blot, and ELISA to assess intestinal barrier integrity. We measured the levels of inflammatory cytokines in serum via ELISA. We also examined blood-brain barrier (BBB) integrity using Evans blue (EB) penetration, transmission electron microscopy (TEM), western blot, and ELISA. Neurological function scores and TTC staining were utilized to evaluate neurological outcomes. RESULTS: We identified twenty-six active components in rhubarb. Rhubarb extract enhanced α-diversity, reduced the abundance of Enterobacteriaceae, and partially rectified metabolic disorders in CIRI rats. It also ameliorated pathological changes, increased the expressions of ZO-1, Occludin, and Claudin 1 in the colon, and reduced levels of LPS and d-lac in serum. Furthermore, it lowered the levels of IL-1ß, IL-6, IL-10, IL-17, and TNF-α in serum. Rhubarb extract mitigated BBB dysfunction, as evidenced by reduced EB penetration and improved hippocampal microstructure. It upregulated the expressions of ZO-1, Occludin, Claudin 1, while downregulating the expressions of TLR4, MyD88, and NF-κB. Similarly, rhubarb extract decreased the levels of IL-1ß, IL-6, and TNF-α in the hippocampus. Ultimately, it reduced neurological function scores and cerebral infarct volume. CONCLUSION: Rhubarb effectively treats CIRI, potentially by inhibiting harmful bacteria, correcting metabolic disorders, repairing intestinal barrier function, alleviating BBB dysfunction, and ultimately improving neurological outcomes.

Oral post-treatment supplementation with a combination of glutamine, citrulline, and antioxidant vitamins additively mitigates jejunal damage, oxidative stress, and inflammation in rats with intestinal ischemia and reperfusion.

INTRODUCTION: Intestinal ischemia and reperfusion (IIR) injury is closely associated with oxidative stress. Evidence shows that oral supplementation with glutamine and citrulline alleviates IIR-induced jejunal damage. We investigated the effects of a combination of glutamine, citrulline, and antioxidant vitamins on IIR-induced jejunal damage, oxidative stress, and inflammation. METHOD: Male Wistar rats that underwent 60 min of superior mesenteric artery occlusion were orally administered glutamine plus citrulline (GC), vitamin C plus E (CE), or a combination of GC and CE 15 min before and 3, 9, and 21 h after reperfusion. Healthy rats without IIR were used as controls. RESULTS: After reperfusion for 24 h, rats with IIR showed lower levels of red blood cells, hemoglobin, serum glucose, and jejunal DNA and increased white blood cell counts compared to controls (1-way ANOVA with the least significant difference, P < 0.05). The IIR-induced decrease in serum albumin and increase in plasma interleukin-6 and jejunal thiobarbituric acid-reactive substances (TBARS) were significantly reversed by GC and/or CE. The results of the 2-way ANOVA indicated that GC was the main factor that increased jejunal villus height and muscularis DNA, and CE was the main factor that increased jejunal muscularis protein and decreased jejunal proinflammatory cytokine levels and myeloperoxidase activity. In addition, GC and CE are the main factors that decrease plasma proinflammatory cytokine levels and the jejunal apoptotic index. CONCLUSION: Oral post-treatment supplementation with glutamine and citrulline, combined with vitamins C and E, may alleviate IIR-induced oxidative stress, inflammation, and jejunal damage.

Impact of folic acid supplementation on ischemia‒reperfusion-induced kidney injury in rats: folic acid prophylactic role revisited.

Folic acid (FA), with its anti-inflammatory and antioxidant properties, may offer protection against ischemia-reperfusion (IR) injury. This study investigated whether FA safeguards rat kidneys from IR by targeting high mobility group box-1 (HMGB1), a key inflammatory mediator. Fifty adult male Wistar rats were randomly allocated into four groups: control, IR, IR + FA pretreatment, and FA alone. Compared to controls, IR significantly impaired renal function and elevated levels of malondialdehyde, HMGB1, NF-κB, and caspase 3. FA pretreatment effectively reversed these detrimental changes, protecting renal function and minimizing tissue damage. The FA-alone group showed no significant differences compared to the control group, indicating no adverse effects of FA treatment. Mechanistically, FA inhibited HMGB1 expression and its downstream activation of NF-κB and caspase 3, thereby quelling inflammation and cell death. FA shields rat kidneys from IR-induced injury by suppressing HMGB1-mediated inflammation and apoptosis, suggesting a potential therapeutic avenue for IR-associated kidney damage.

Electroacupuncture ameliorates neuroinflammation by inhibiting TRPV4 channel in ischemic stroke.

AIMS: We investigated the potential mechanisms underlying the therapeutic efficacy of electroacupuncture (EA) at the Shuigou (GV26) and Baihui (GV20) acupoints in the treatment of ischemic stroke. METHODS: We assessed the therapeutic effects of EA on MCAO mice through behavioral studies and TTC staining. Various techniques, such as RT-PCR, immunofluorescence, and Western blots, were employed to evaluate the activation and polarization of microglia/macrophages, and changes in the TRPV4 ion channel. We used the TRPV4 antagonist GSK2193874 (GSK219) to verify the involvement of TRPV4 in the therapeutic effects of EA. RESULTS: EA effectively improved neurological impairments and reduced cerebral infarction volume in MCAO mice. It suppressed activated microglia/macrophages and inhibited their polarization toward the M1 phenotype post-MCAO. EA also downregulated the expression of pro-inflammatory cytokines, including Tnf-α, Il-6, Il-1ß, and Ccl-2 mRNA. Furthermore, EA reduced the elevated expression of TRPV4 following MCAO. Treatment with the TRPV4 antagonist GSK219 mirrored the effects of EA in MCAO mice. Notably, the combination of EA and GSK219 did not demonstrate an additive or synergistic effect. CONCLUSION: EA may inhibit neuroinflammation and exhibit a protective effect against ischemic brain injury by suppressing TRPV4 and the subsequent M1 polarization of microglia/macrophages.

Luminal Delivery of Pectin-Modified Oxygen Microbubbles Mitigates Rodent Experimental Intestinal Ischemia.

INTRODUCTION: Ischemic gut injury is common in the intensive care unit, impairs gut barrier function, and contributes to multiorgan dysfunction. One novel intervention to mitigate ischemic gut injury is the direct luminal delivery of oxygen microbubbles (OMB). Formulations of OMB can be modified to control the rate of oxygen delivery. This project examined whether luminal delivery of pectin-modified OMB (OMBp5) can reduce ischemic gut injury in a rodent model. METHODS: The OMBp5 formulation was adapted to improve delivery of oxygen along the length of small intestine. Adult Sprague-Dawley rats (n = 24) were randomly allocated to three groups: sham-surgery (SS), intestinal ischemia (II), and intestinal ischemia plus luminal delivery of OMBp5 (II + O). Ischemia-reperfusion injury was induced by superior mesenteric artery occlusion for 45 min followed by reperfusion for 30 min. Outcome data included macroscopic score of mucosal injury, the histological score of gut injury, and plasma biomarkers of intestinal injury. RESULTS: Macroscopic, microscopic data, and intestinal injury biomarker results demonstrated minimal intestinal damage in the SS group and constant damage in the II group. II + O group had a significantly improved macroscopic score throughout the gut mucosa (P = 0.04) than the II. The mean histological score of gut injury for the II + O group was significantly improved on the II group (P ≤ 0.01) in the proximal intestine only, within 30 cm of delivery. No differences were observed in plasma biomarkers of intestinal injury following OMBp5 treatment. CONCLUSIONS: This proof-of-concept study has demonstrated that luminal OMBp5 decreases ischemic injury to the proximal small intestine. There is a need to improve oxygen delivery over the full length of the intestine. These findings support further studies with clinically relevant end points, such as systemic inflammation and vital organ dysfunction.

Effect of electroacupuncture on neuronal programmed necrosis by regulating RIP1/RIP3/MLKL pathway in rats with cerebral ischemia reperfusion injury. / 电针调节RIP1/RIP3/MLKLé€šè·¯å¯¹è„‘ç¼ºè¡€å†çŒæ³¨æŸä¼¤å¤§é¼ ç¥žç»å ƒç¨‹åºæ€§åæ­»çš„å½±å“.

OBJECTIVES: To investigate the neuroprotective effect of electroacupuncture (EA) at "Quchi"(LI11) and "Zusanli"(ST36) in the rats with cerebral ischemia reperfusion injury and its influence on programmed necrosis of cerebral cortical neurons. METHODS: Sixty male SD rats were randomly divided into sham-operation group, model group, EA group and inhibitor group, with 15 rats in each group. Left middle cerebral artery occlusion model was established using the modified thread embolism method. In the sham-operation group, the carotid artery was exposed and dissociated in each rat. EA was applied to "Quchi"(LI11) and "Zusanli"(ST36) on the right side for 30 min each time, once daily for 7 days in the rats of the EA group. The rats in the inhibitor group were intraperitoneally injected with norstatin-1 (0.6 mg/kg) for consecutive 7 days. The neurological deficit score of rats in each group was observed. HE staining was adopted to detect the degree of pathological damage of the cerebral cortex in the infarction area. Using TUNEL staining, the apoptosis of cortical neurons in the infarction area was determined；the contents of tumor necrosis factor α (TNF-α), interleukin (IL)-1ß and IL-6 were detected by ELISA；the mRNA and protein expression of the receptor interacting protein-1 (RIP1), the receptor interacting protein-3 (RIP3) and the substrate mixed lineage kinase like protein (MLKL) were detected by fluorescence quantitative PCR and Western blot, respectively. RESULTS: In comparison with the sham-operation group, the neurological deficit score in the model group was higher(P<0.01)；HE staining showed that there was the pathological damage in the infarction area；the neuron apoptosis rate, the contents of TNF-α, IL-1ß and IL-6, and the mRNA and protein expressions of RIP1, RIP3 and MLKL increased(P<0.01) in the model group. In the EA group, the neurological deficit score was reduced(P<0.01)；HE staining showed that the pathological damage was ameliorated in the infarction area；the neuron apoptosis rate, the contents of TNF-α, IL-1ß and IL-6, and the mRNA and protein expressions of RIP1, RIP3, MLKL decreased(P<0.05, P<0.01) when compared with those in the model group. CONCLUSIONS: EA can attenuate cerebral ischemia reperfusion injury and display its neuroprotective effect probably through inhibiting programmed necrosis of cerebral cortical neurons in the rats.

20(R)-ginsenoside Rg3 attenuates cerebral ischemia-reperfusion injury by mitigating mitochondrial oxidative stress via the Nrf2/HO-1 signaling pathway.

Reducing mitochondrial oxidative stress has become an important strategy to prevent neuronal death in ischemic stroke. Previous studies have shown that 20(R)-ginsenoside Rg3 can significantly improve behavioral abnormalities, reduce infarct size, and decrease the number of apoptotic neurons in cerebral ischemia/reperfusion injury rats. However, it remains unclear whether 20(R)-ginsenoside Rg3 can inhibit mitochondrial oxidative stress in ischemic stroke and the potential molecular mechanism. In this study, we found that 20(R)-ginsenoside Rg3 notably inhibited mitochondrial oxidative stress in middle cerebral artery occlusion/reperfusion (MCAO/R) rats and maintained the stability of mitochondrial structure and function. Treatment with 20(R)-ginsenoside Rg3 also decreased the levels of mitochondrial fission proteins (Drp1 and Fis1) and increased the levels of fusion proteins (Opa1, Mfn1, and Mfn2) in MCAO/R rats. Furthermore, we found that 20(R)-ginsenoside Rg3 promoted nuclear aggregation of nuclear factor erythroid2-related factor 2 (Nrf2) but did not affect Kelch-like ECH-associated protein-1 (Keap1), resulting in the downstream expression of antioxidants. In in vitro oxygen-glucose deprivation/reperfusion stroke models, the results of PC12 cells treated with 20(R)-ginsenoside Rg3 were consistent with animal experiments. After transfection with Nrf2 short interfering RNA (siRNA), the protective effect of 20(R)-ginsenoside Rg3 on PC12 cells was reversed. In conclusion, the inhibition of mitochondrial oxidative stress plays a vital position in the anti-cerebral ischemia-reperfusion injury of 20(R)-ginsenoside Rg3, and its neuroprotective mechanism is related to the activation of the nuclear factor erythroid2-related factor 2/heme oxygenase 1 signaling pathway.