N-acetylcysteine alleviates post-resuscitation myocardial dysfunction and improves survival outcomes via partly inhibiting NLRP3 inflammasome induced-pyroptosis

N-Acetylcysteine Inhibits Coxsackievirus B3 Replication by Downregulating Eukaryotic Translation Elongation Factor 1 Alpha 1

Group B Coxsackieviruses (CVB) are one of the causative pathogens of myocarditis, which may progress to cardiomyopathy. The pathogenesis of CVB is not fully understood, and effective antiviral therapy is not available. N-acetylcysteine (NAC), the classic antioxidant, has been used in clinical practice for several decades to treat various medical conditions. In this study, the anti-CVB effect of NAC was investigated. We show that NAC dramatically suppressed viral replication and alleviated cardiac injury induced by CVB3. To further study the antiviral mechanism of NAC, RNA-sequencing was performed for CVB3-infected cells with NAC treatment. We found that eukaryotic elongation factor 1 alpha 1 (EEF1A1) is one of the most upregulated genes in CVB3-infected cells. However, EEF1A2, the highly homologous isoform of EEF1A1, remains unchanged. EEF1A1 expression was significantly suppressed by NAC treatment in CVB3-infected cells, while EEF1A2 was not affected. eEF1A1 knockdown significantly inhibited CVB3 replication, implicating that eEF1A1 facilitates viral replication. Importantly, we show that eEF1A1, which was not expressed in the myocardia of newborn mice, was significantly upregulated by CVB3 infection. NAC markedly downregulated the expression of eEF1A1 but not eEF1A2 in the myocardia of CVB3-infected mice. Furthermore, NAC accelerated eEF1A1 degradation by promoting autophagy in CVB3-infected cells. We show that p62, one of the critical adaptors of autophagic targets, interacts with eEF1A1 and was downregulated in CVB3-infected cells upon NAC treatment. Taken together, this study demonstrated that NAC shows a potent anti-CVB effect through the downregulation of eEF1A1.

Neuroprotective Approaches for Brain Injury After Cardiac Arrest: Current Trends and Prospective Avenues

With the implementation of improved bystander cardiopulmonary resuscitation techniques and public-access defibrillation, survival after out-of-hospital cardiac arrest (OHCA) has increased significantly over the years. Nevertheless, OHCA survivors have residual anoxia/reperfusion brain damage and associated neurological impairment resulting in poor quality of life. Extracorporeal membrane oxygenation or targeted temperature management has proven effective in improving post-cardiac arrest (CA) neurological outcomes, yet considering the substantial healthcare costs and resources involved, there is an urgent need for alternative treatment strategies that are crucial to alleviate brain injury and promote recovery of neurological function after CA. In this review, we searched PubMed for the latest preclinical or clinical studies (2016-2023) utilizing gas-mediated, pharmacological, or stem cell-based neuroprotective approaches after CA. Preclinical studies utilizing various gases (nitric oxide, hydrogen, hydrogen sulfide, carbon monoxide, argon, and xenon), pharmacological agents targeting specific CA-related pathophysiology, and stem cells have shown promising results in rodent and porcine models of CA. Although inhaled gases and several pharmacological agents have entered clinical trials, most have failed to demonstrate therapeutic effects in CA patients. To date, stem cell therapies have not been reported in clinical trials for CA. A relatively small number of preclinical stem-cell studies with subtle therapeutic benefits and unelucidated mechanistic explanations warrant the need for further preclinical studies including the improvement of their therapeutic potential. The current state of the field is discussed and the exciting potential of stem-cell therapy to abate neurological dysfunction following CA is highlighted.

The role of novel programmed cell death in head and neck squamous cell carcinoma: from mechanisms to potential therapies

Head and neck squamous cell carcinoma (HNSCC) is a common oral cancer with poor prognosis and for which no targeted therapeutic strategies are currently available. Accumulating evidence has demonstrated that programmed cell death (PCD) is essential in the development of HNSCC as a second messenger. PCD can be categorized into numerous different subroutines: in addition to the two well-known types of apoptosis and autophagy, novel forms of programmed cell death (e.g., necroptosis, pyroptosis, ferroptosis, and NETosis) also serve as key alternatives in tumorigenesis. Cancer cells are not able to avoid all types of cell death simultaneously, since different cell death subroutines follow different regulatory pathways. Herein, we summarize the roles of novel programmed cell death in tumorigenesis and present our interpretations of the molecular mechanisms with a view to the development of further potential therapies.

Multi-Drug Cocktail Therapy Improves Survival and Neurological Function after Asphyxial Cardiac Arrest in Rodents

BACKGROUND

Cardiac arrest (CA) can lead to neuronal degeneration and death through various pathways, including oxidative, inflammatory, and metabolic stress. However, current neuroprotective drug therapies will typically target only one of these pathways, and most single drug attempts to correct the multiple dysregulated metabolic pathways elicited following cardiac arrest have failed to demonstrate clear benefit. Many scientists have opined on the need for novel, multidimensional approaches to the multiple metabolic disturbances after cardiac arrest. In the current study, we have developed a therapeutic cocktail that includes ten drugs capable of targeting multiple pathways of ischemia-reperfusion injury after CA. We then evaluated its effectiveness in improving neurologically favorable survival through a randomized, blind, and placebo-controlled study in rats subjected to 12 min of asphyxial CA, a severe injury model.

RESULTS

14 rats were given the cocktail and 14 received the vehicle after resuscitation. At 72 h post-resuscitation, the survival rate was 78.6% among cocktail-treated rats, which was significantly higher than the 28.6% survival rate among vehicle-treated rats (log-rank test; p = 0.006). Moreover, in cocktail-treated rats, neurological deficit scores were also improved. These survival and neurological function data suggest that our multi-drug cocktail may be a potential post-CA therapy that deserves clinical translation.

CONCLUSIONS

Our findings demonstrate that, with its ability to target multiple damaging pathways, a multi-drug therapeutic cocktail offers promise both as a conceptual advance and as a specific multi-drug formulation capable of combatting neuronal degeneration and death following cardiac arrest. Clinical implementation of this therapy may improve neurologically favorable survival rates and neurological deficits in patients suffering from cardiac arrest.

Gasdermin D Deficiency in Vascular Smooth Muscle Cells Ameliorates Abdominal Aortic Aneurysm Through Reducing Putrescine Synthesis

Abdominal aortic aneurysm (AAA) is a common vascular disease associated with significant phenotypic alterations in vascular smooth muscle cells (VSMCs). Gasdermin D (GSDMD) is a pore-forming effector of pyroptosis. In this study, the role of VSMC-specific GSDMD in the phenotypic alteration of VSMCs and AAA formation is determined. Single-cell transcriptome analyses reveal Gsdmd upregulation in aortic VSMCs in angiotensin (Ang) II-induced AAA. VSMC-specific Gsdmd deletion ameliorates Ang II-induced AAA in apolipoprotein E (ApoE)^-/- mice. Using untargeted metabolomic analysis, it is found that putrescine is significantly reduced in the plasma and aortic tissues of VSMC-specific GSDMD deficient mice. High putrescine levels trigger a pro-inflammatory phenotype in VSMCs and increase susceptibility to Ang II-induced AAA formation in mice. In a population-based study, a high level of putrescine in plasma is associated with the risk of AAA (p < 2.2 × 10^-16 ), consistent with the animal data. Mechanistically, GSDMD enhances endoplasmic reticulum stress-C/EBP homologous protein (CHOP) signaling, which in turn promotes the expression of ornithine decarboxylase 1 (ODC1), the enzyme responsible for increased putrescine levels. Treatment with the ODC1 inhibitor, difluoromethylornithine, reduces AAA formation in Ang II-infused ApoE^-/- mice. The findings suggest that putrescine is a potential biomarker and target for AAA treatment.

Protection Against Post-resuscitation Acute Kidney Injury by N-Acetylcysteine via Activation of the Nrf2/HO-1 Pathway

Background and Objective

Acute kidney injury (AKI), the common complication after cardiopulmonary resuscitation (CPR), seriously affects the prognosis of cardiac arrest (CA) patients. However, there are limited studies on post-resuscitation AKI. In addition, it has been demonstrated that N-acetylcysteine (N-AC) as an ROS scavenger, has multiorgan-protective effects on systemic and regional ischaemia-reperfusion injuries. However, no studies have reported its protective effects against post-resuscitation AKI and potential mechanisms. This study aimed to clarify the protective effects of N-AC on post-resuscitation AKI and investigate whether its potential mechanism was mediated by activating Nrf-2/HO-1 pathway in the kidney.

Methods

We established cardiac arrest models in rats. All animals were divided into four groups: the sham, control, N-AC, and ZnPP groups. Animals in each group except for the ZnPP group were assigned into two subgroups based on the survival time: 6 and 48 h. The rats in the control, N-AC, and ZnPP groups underwent induction of ventricular fibrillation (VF), 8 min untreated VF and cardiopulmonary resuscitation. Renal function indicators, were detected using commercial kits. Renal pathologic changes were assessed by haematoxylin–eosin (HE) staining. Oxidative stress and inflammatory responses were measured using the corresponding indicators. Apoptosis was evaluated using terminal uridine nick-end labeling (TUNEL) staining, and expression of proteins associated with apoptosis and the Nrf-2/HO-1 pathway was measured by western blotting.

Results

N-AC inhibited post-resuscitation AKI. We observed that N-AC reduced the levels of biomarkers of renal function derangement; improved renal pathological changes; and suppressed apoptosis, oxidative stress, and inflammatory response. Additionally, the production of ROS in the kidneys markedly decreased by N-AC. More importantly, compared with the control group, N-AC further upregulated the expression of nuclear Nrf2 and endogenous HO-1 in N-AC group. However, N-AC-determined protective effects on post-resuscitation AKI were markedly reversed after pretreatment of the HO-1 inhibitor zinc protoporphyrin (ZnPP).

Conclusions

N-AC alleviated renal dysfunction and prolonged survival in animal models of CA. N-AC partially exerts beneficial renal protection via activation of the Nrf-2/HO-1 pathway. Altogether, all these findings indicated that N-AC as a common clinical agent, may have the potentially clinical utility to improve patients the outcomes in cardiac arrest.

Curcumin Improves Cardiopulmonary Resuscitation Outcomes by Modulating Mitochondrial Metabolism and Apoptosis in a Rat Model of Cardiac Arrest

Background

Curcumin, a diarylheptanoid chemical compound extracted from curcuma longa, exerts a variety of biological and pharmacological effects in numerous pathological conditions, including ischemia/reperfusion (I/R) injury. In this study, we investigated its role in post-resuscitation myocardial dysfunction in a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) by targeting on mitochondrial metabolism and apoptosis.

Methods

Animals were randomized into three groups: sham, control and curcumin, with fifteen rats in each group. Ventricular fibrillation (VF) was induced in the rats of the control and curcumin groups. The rats in the two groups were untreated for 8 min, followed by CPR for 8 min. Placebo (saline) or curcumin was administered by intraperitoneal injection, respectively, 5 min after successful resuscitation. Myocardial function was measured at baseline and post-resuscitation for 6 h consecutively. Ten rats in each group were closely observed for an additional 66 h to analyze the survival status, and the remaining five were sacrificed for the measurement of mitochondrial parameters and cell apoptosis.

Results

Compared with the control group, myocardial function was significantly enhanced in the curcumin group, contributing to a better survival status. Curcumin treatment mitigated the depletion of superoxide dismutase (SOD) and the production of malondialdehyde (MDA). The structural damage of mitochondria was also alleviated, with improved conditions of mPTP and ΔΨm. Curcumin boosted the production of ATP and attenuated myocardial apoptosis. Cytochrome C, caspase-3 and its cleavage were suppressed by curcumin. Proteins closely related to the functional performance of mitochondria, including uncoupling protein 2 (UCP2) and uncoupling protein 3 (UCP3) were downregulated, while mitochondrial transcription factor A (mtTFA) was upregulated.

Conclusion

Curcumin improves the outcomes of CPR via alleviating myocardial dysfunction induced by I/R injury. It exhibits anti-oxidation properties. Moreover, it is capable of ameliorating mitochondrial structure and energy metabolism, as well as inhibiting the mitochondrial apoptosis pathway. UCP2, UCP3, and mtTFA might also be involved in curcumin mediated protective effects on mitochondria.

Icariin protects podocytes from NLRP3 activation by Sesn2-induced mitophagy through the Keap1-Nrf2/HO-1 axis in diabetic nephropathy

BACKGROUND

Icariin (ICA) is a flavonoid extract obtained from Herba epimedii that has been proven to exert multiple pharmacological activities, including antifibrotic and anti-inflammatory activities.

PURPOSE

This study aimed to investigate the ameliorative mechanism of ICA in diabetes mellitus rats and MPC-5 cells.

METHODS

We administered ICA at 3 different dosages (20 mg/kg, 40 mg/kg, 80 mg/kg) to streptozotocin (STZ)-treated rats and (1 μM, 3 μM, 10 μM) to high glucose (HG)-treated MPC-5 cells. We also chose irbesartan (IRB) (13.5 mg/kg in rats, 1 μM in cells) as a positive control drug to evaluate the ICA pharmacological effect. After administration, the kidneys of rats and MPC-5 cells were harvested for experiments.

RESULTS

After 8 weeks of oral administration, we found that the physiological index was improved by ICA and IRB. The results of immunohistochemistry, Western blot, and laser confocal imaging showed that mitophagy might play a key role in ICA-induced improvement. In further research, we found that ICA could activate Nrf2, suppress NLRP3 and degrade Keap1 via Sesn2-dependant mitophagy. To verify our hypothesis, we blocked the mitophagy signalling pathway via Sesn2 siRNA. The results showed that ICA-induced NLRP3 suppression and mitophagy vanished.

CONCLUSION

In summary, we conclude that ICA can increase Sesn2-induced mitophagy to inhibit NLRP3 inflammasome activation by the Keap1-Nrf2/HO-1 axis in diabetic nephropathy rats. This might be the underlying mechanism of ICA's protective effect in diabetic nephropathy.

Tubastatin A Improves Post-Resuscitation Myocardial Dysfunction by Inhibiting NLRP3-Mediated Pyroptosis Through Enhancing Transcription Factor EB Signaling

Background

Myocardial dysfunction is the leading cause of early death following successful cardiopulmonary resuscitation (CPR) in people with cardiac arrest (CA), which is potentially driven by cell pyroptosis mediated by NOD‐like receptor pyrin domain 3 (NLRP3) inflammasome. Recently, histone deacetylase 6 (HDAC6) inhibition was shown to exert effective myocardial protection against regional ischemia/reperfusion injury. In this study, we investigated whether tubastatin A, a specific histone deacetylase 6 inhibitor, could improve postresuscitation myocardial dysfunction through the inhibition of NLRP3‐mediated cell pyroptosis and its modulation mechanism.

Methods and Results

Healthy male white domestic swine were used to establish the model of CA/CPR in vivo, and the H9c2 cardiomyocyte hypoxia/reoxygenation model was used to simulate the CA/CPR process in vitro. Consequently, tubastatin A inhibited NLRP3 inflammasome activation, decreased proinflammatory cytokines production and cell pyroptosis, and increased cell survival after hypoxia/reoxygenation in H9c2 cardiomyocytes in vitro. In addition, tubastatin A increased the acetylated levels of transcription factor EB and its translocation to the nucleus, and its protective effect above was partly abrogated by transcription factor EB short interfering RNA after hypoxia/reoxygenation in H9c2 cardiomyocytes. Similarly, tubastatin A promoted cardiac transcription factor EB nuclear translocation, inhibited NLRP3‐mediated cell pyroptosis, and mitigated myocardial dysfunction after CA/CPR in swine.

Conclusions

The inhibition of histone deacetylase 6 activity by tubastatin A limited NLRP3 inflammasome activation and cell pyroptosis probably through the enhancement of transcription factor EB signaling, and therefore improved myocardial dysfunction after CA/CPR.

Vitamin C Improves the Outcomes of Cardiopulmonary Resuscitation and Alters Shedding of Syndecan-1 and p38/MAPK Phosphorylation in a Rat Model

Background

Post‐resuscitation syndrome, involves a severe inflammatory response following successful cardiopulmonary resuscitation. The potential mechanism of Vitamin C (VitC) after cardiopulmonary resuscitation on myocardial and cerebral function, duration of survival is undefined.

Methods and Results

A first set of experiments were done in 18 male Sprague‐Dawley rats for the investigation of short‐term follow‐up, randomized into 3 groups: (1) sham; (2) controls; (3) VitC. Ventricular fibrillation was electrically induced and untreated for 6 minutes. Cardiopulmonary resuscitation including chest compression and mechanical ventilation were then initiated and continued for 8 minutes followed by defibrillation. At 5 minutes after return of spontaneous circulation, either VitC (200 mg/kg) or placebo was administered by intravenous infusion with a syringe pump for half an hour. There were significant improvements in myocardial function and buccal microcirculation in rats treated with VitC after return of spontaneous circulation 4 hours compared with controls. VitC inhibited proinflammatory cytokines (interleukin‐6 and tumor necrosis factor‐α), SDC‐1 (Syndecan‐1), and hyaluronic acid in plasma compared with controls (P<0.01). VitC decreased reactive oxygen species production and inhibited p38/MAPK (mitogen‐activated protein kinase) pathway phosphorylation. A second set with 20 animals was used for assessing the neurological deficit score after return of spontaneous circulation 72 hours, randomized into 2 groups: 1) controls; 2) VitC. The survival rate and neurological deficit score after return of spontaneous circulation 72 hours were improved in VitC‐treated animals compared with those of the control group.

Conclusions

VitC reduces the severity of post‐resuscitation myocardial and cerebral dysfunction and improves the survival. The mechanisms may involve inhibiting transcription of inflammatory cytokines and oxidative stress, thus protecting the integrity of the vascular endothelium. Meanwhile VitC reduces shedding of SDC‐1 and alters p38/MAPK phosphorylation and microcirculation.

Mesenchymal Stem Cells Alleviate Post-resuscitation Cardiac and Cerebral Injuries by Inhibiting Cell Pyroptosis and Ferroptosis in a Swine Model of Cardiac Arrest

Following cardiopulmonary resuscitation (CPR), the ensuing cardiac and cerebral injuries contribute to the poor outcome of cardiac arrest (CA) victims, in which the pathogenetic process is possibly driven by cell pyroptosis and ferroptosis. Mesenchymal stem cells (MSCs) have been shown to be a promising strategy for post-resuscitation cardiac and cerebral protection in rat, but its effectiveness in the clinically relevant swine model and the potential protective mechanism remain unknown. The present study was designed to investigate whether MSCs administration could alleviate post-resuscitation cardiac and cerebral injuries through the inhibition of cell pyroptosis and ferroptosis in swine. Twenty-four male domestic swine were randomly divided into three groups: sham, CPR, and MSC. A dose of 2.5×106/kg of MSCs derived from human embryonic stem cells was intravenously infused at 1.5, and 3 days prior to CA. The animal model was established by 8 min of CA and then 8 min of CPR. After resuscitation, cardiac, cerebral function and injury biomarkers were regularly evaluated for a total of 24 h. At 24 h post-resuscitation, pyroptosis-related proteins (NLRP3, ASC, cleaved caspase-1, GSDMD), proinflammatory cytokines (IL-1β, IL-18), ferroptosis-related proteins (ACSL4, GPX4) and iron deposition in the heart, cortex and hippocampus were measured. Consequently, significantly greater cardiac, cerebral dysfunction and injuries after resuscitation were observed in the CPR and MSC groups compared with the sham group. However, the severity of cardiac and cerebral damage were significantly milder in the MSC group than in the CPR group. In addition, the expression levels of NLRP3, ASC, cleaved caspase-1, GSDMD and ACSL4, the contents of IL-1β and IL-18, and the level of iron deposition were significantly higher while the expression level of GPX4 was significantly lower in the heart, cortex and hippocampus in all resuscitated animals compared with the sham group. Nevertheless, MSCs administration significantly decreased post-resuscitation cardiac, cerebral pyroptosis and ferroptosis compared to the CPR group. Our results showed that the administration of MSCs significantly alleviated post-resuscitation cardiac and cerebral injuries in swine, in which the protective effects were related to the inhibition of cell pyroptosis and ferroptosis.

Cardioprotective activity of ethyl acetate extract of Cinnamomi Ramulus against myocardial ischemia/reperfusion injury in rats via inhibiting NLRP3 inflammasome activation and pyroptosis

BACKGROUND

NLRP3 inflammasome activation and pyroptosis play an important role in myocardial ischemia/reperfusion injury (MI/RI). Cinnamomi ramulus (CR), is an important folk medicinal plant in China, which derived from the dried twig of Cinnamomum cassia (L.) Presl, has function of "warming and tonifying heart yang", and traditionally utilized to treat the cold, blood-cold amenorrhea, phlegm, edema, arthralgia, and palpitations as well as improve blood circulation. The aqueous extract of C. ramulus was reported to show significant therapeutic potential for treating MI/RI. Whereas, there are no previous investigations in China or abroad has reported the cardioprotective effects and underlying mechanism of the ethyl acetate extract of C. ramulus (CREAE) and its bioactive substance cinnamic acid (CA) in triggering NLRP3 inflammasome activation and subsequent pyroptosis.

PURPOSE

The present study aimed to assess the cardioprotective function of CREAE and CA against the MI/RI in rats and involved the underlying mechanisms.

METHODS

The MI/RI model was established in male SD rats by occlusion of the left anterior descending coronary artery for 30 min followed by reperfusion for 120 min, respectively. The rats were intragastrically administered with CREAE (74 and 37 mg/kg) and CA (45 mg/kg) for 7 successive days before vascular ligation. The cardioprotective effects of CREAE and CA against myocardial injury of rats were detected by HE staining, TTC staining, echocardiograms, and myocardial enzymes detections. Serum levels of inflammatory factors, such as IL-6, IL-1β, and TNF-α, were analyzed by ELISA kits to evaluate the effects of CREAE and CA. The protein and gene expression levels of NLRP3 and the pyroptosis-related factors in heart tissue were conducted by western blot and RT-qPCR.

RESULTS

Our results showed that CREAE and CA decrease myocardial infarct size and improve cardiac function, mitigate myocardial damage, and repress inflammatory response in rats after I/R. Mechanistically, our results revealed that CREAE and CA can dramatically suppress the activation of NLRP3 inflammasome and subsequent cardiomyocyte pyroptosis in myocardial tissues that as evidenced by downregulating the protein and gene expressions of NLRP3, ASC, IL-1β, caspase-1, gasdermin D, and N-terminal GSDMD.

CONCLUSIONS

Our data indicated that CREAE and CA may attenuate MI/RI through suppression of NLRP3 inflammasome and subsequent pyroptosis-related signaling pathways.

LncRNAs Participate in Post-Resuscitation Myocardial Dysfunction Through the PI3K/Akt Signaling Pathway in a Rat Model of Cardiac Arrest and Cardiopulmonary Resuscitation

In this study, we aimed to explore the role of lncRNAs in post-resuscitation myocardial dysfunction in a rat model of CA-CPR. A rat model of CA-CPR was constructed using a VF method. Myocardial functions, including cardiac output (CO), ejection fraction (EF), and myocardial performance index (MPI), were evaluated at the baseline, and 1, 2, 3, 4, and 6 h after resuscitation. A high throughput sequencing method was used to screen the differentially expressed lncRNAs, miRNAs, and mRNAs, which were further analyzed with bioinformatics. In addition, relationships between the molecules involved in the PI3K/Akt signaling pathway were explored with ceRNA network. Compared with the sham group, EF was significantly reduced and MPI was increased at the five consecutive time points in the CA-CPR group. 68 lncRNAs were upregulated and 40 lncRNAs were downregulated in the CA-CPR group, while 30 miRNAs were downregulated and 19 miRNAs were upregulated. Moreover, mRNAs were also differentially expressed, with 676 upregulated and 588 downregulated. GO analysis suggested that genes associated with cell proliferation, cell death and programmed cell death were significantly enriched. KEGG analysis showed that the PI3K/Akt, MAPK and Ras signaling pathways were the three most-enriched pathways. Construction of a ceRNA regulatory network indicated that LOC102549506, LOC103689920, and LOC103690137 might play important roles in the regulation of the PI3K/Akt signaling pathway in the CA-CPR treated rat. Taken together, LncRNAs, including LOC102549506, LOC103689920 and LOC103690137, might participate in post-resuscitation myocardial dysfunction by functioning as ceRNAs and regulating the PI3K/Akt signaling pathway.

Pharmacological Approach for Neuroprotection After Cardiac Arrest-A Narrative Review of Current Therapies and Future Neuroprotective Cocktail

Cardiac arrest (CA) results in global ischemia-reperfusion injury damaging tissues in the whole body. The landscape of therapeutic interventions in resuscitation medicine has evolved from focusing solely on achieving return of circulation to now exploring options to mitigate brain injury and preserve brain function after CA. CA pathology includes mitochondrial damage and endoplasmic reticulum stress response, increased generation of reactive oxygen species, neuroinflammation, and neuronal excitotoxic death. Current non-pharmacologic therapies, such as therapeutic hypothermia and extracorporeal cardiopulmonary resuscitation, have shown benefits in protecting against ischemic brain injury and improving neurological outcomes post-CA, yet their application is difficult to institute ubiquitously. The current preclinical pharmacopeia to address CA and the resulting brain injury utilizes drugs that often target singular pathways and have been difficult to translate from the bench to the clinic. Furthermore, the limited combination therapies that have been attempted have shown mixed effects in conferring neuroprotection and improving survival post-CA. The global scale of CA damage and its resultant brain injury necessitates the future of CA interventions to simultaneously target multiple pathways and alleviate the hemodynamic, mitochondrial, metabolic, oxidative, and inflammatory processes in the brain. This narrative review seeks to highlight the current field of post-CA neuroprotective pharmaceutical therapies, both singular and combination, and discuss the use of an extensive multi-drug cocktail therapy as a novel approach to treat CA-mediated dysregulation of multiple pathways, enhancing survival, and neuroprotection.

miR-194-5p protects against myocardial ischemia/reperfusion injury via MAPK1/PTEN/AKT pathway

Background

MicroRNA (miRNA), which participates in various physiological and pathological processes, is a highly conserved small RNA sequence. This study aimed to investigate the role of miR-194-5p in hypoxia/reoxygenation (H/R)-induced cardiomyocyte apoptosis and myocardial ischemia/reperfusion (I/R) injury.

Methods

We set up an H/R H9c2 cell model in vitro and an I/R mouse model in vivo. Then, cell vitality, apoptosis, and histopathological evaluation were conducted. Reactive oxygen species (ROS) generation and the activity of superoxide dismutase (SOD) and malondialdehyde (MDA) were examined by 2’,7’-Dichlorodihydrofluorescein diacetate (H2DCFDA), and enzyme-linked immunosorbent assay (ELISA), respectively. The level of creatine kinase isoenzyme (CK-MB), cardiac troponin I (cTnI), myoglobin (Mb) is examined by ELISA. The expression of Caspase-3, cleaved-Caspase-3, Bax, Bcl-2, phosphatase and tensin homolog deleted on chromosome ten (PTEN), and protein kinase B (AKT) was analyzed by western blot.

Results

Data showed the expression of miR-194-5p was decreased in H/R-induced H9c2 cells and I/R-induced mouse. Conversely, overexpression of miR-194-5p could improve cardiomyocyte damage in ischemic models in vivo and in vitro. Furthermore, mitogen-activated protein kinase 1 (MAPK1) was found as a direct target of miR-194-5p, which negatively regulated the expression of MAPK1. The up-regulation of MAPK1 inhibited the myocardial protection previously observed by miR-194-5p.

Conclusions

Our study shows overexpression of miR-194-5p protects against H/R injury in vitro and cardiac I/R injury in vivo, which involves the inhibition of cardiac apoptosis and oxidative stress by targeting MAPK1 expression via PTEN/AKT pathway. These findings supply novel insights into potential therapeutic targets for cardiovascular diseases.

Betulinic acid inhibits pyroptosis in spinal cord injury by augmenting autophagy via the AMPK-mTOR-TFEB signaling pathway

Spinal cord injury (SCI) results in a wide range of disabilities. Its complex pathophysiological process limits the effectiveness of many clinical treatments. Betulinic acid (BA) has been shown to be an effective treatment for some neurological diseases, but it has not been studied in SCI. In this study, we assessed the role of BA in SCI and investigated its underlying mechanism. We used a mouse model of SCI, and functional outcomes following injury were assessed. Western blotting, ELISA, and immunofluorescence techniques were employed to analyze levels of autophagy, mitophagy, pyroptosis, and AMPK-related signaling pathways were also examined. Our results showed that BA significantly improved functional recovery following SCI. Furthermore, autophagy, mitophagy, ROS level and pyroptosis were implicated in the mechanism of BA in the treatment of SCI. Specifically, our results suggest that BA restored autophagy flux following injury, which induced mitophagy to eliminate the accumulation of ROS and inhibits pyroptosis. Further mechanistic studies revealed that BA likely regulates autophagy and mitophagy via the AMPK-mTOR-TFEB signaling pathway. Those results showed that BA can significantly promote the recovery following SCI and that it may be a promising therapy for SCI.