Lidocaine improves cerebral ischemia-reperfusion injury in rats through cAMP/PKA signaling pathway

The involvement of lidocaine in amyloid-β1-42-dependent mitochondrial dysfunction and apoptosis in hippocampal neurons via nerve growth factor-protein kinase B pathway

This project is conceived to reveal the role of lidocaine in the process of Alzheimer's disease (AD) and its possible downstream targets. After the employment of AD cell model in mice hippocampal neuronal HT-22 cells in the presence of amyloid-β1-42 (Aβ1-42), Cell Counting Kit-8 method investigated cell viability. Oxidative damage was assayed based on a dichloro-dihydro-fluorescein diacetate fluorescent probe and commercially available kits. The 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine iodide fluorescent probe estimated mitochondrial function. Terminal-deoxynucleotidyl transferase mediated nick end labeling, western blotting, and immunofluorescence appraised the apoptotic level. Western blot also ascertained the alternations of nerve growth factors (NGF)-protein kinase B (Akt) pathway-related proteins. Aβ1-42 concentration dependently triggered the viability loss, oxidative damage, and apoptosis in HT-22 cells. Lidocaine promoted the viability and reduced the mitochondrial impairment and mitochondria-dependent apoptosis in Aβ1-42-treated HT-22 cells in a concentration-dependent manner. Besides, lidocaine activated the NGF-Akt pathway and NGF absence blocked NGF-Akt pathway, aggravated mitochondrial dysfunction as well as mitochondria-dependent apoptosis in lidocaine-administrated HT-22 cells in response to Aβ1-42. Altogether, these observations concluded that lidocaine might stimulate NGF-Akt pathway to confer protection against mitochondrial impairment and apoptosis in Aβ1-42-mediated cellular model of AD.

Protective effect of MitoTEMPO against cardiac dysfunction caused by ischemia-reperfusion: MCAO stroke model study

PURPOSE

Neurological impairments are the leading cause of post-stroke mortality, while stroke-related cardiovascular diseases rank second in significance. This study investigates the potential protective effects of MitoTEMPO (2,2,6,6-tetramethyl-4-[[2-(triphenylphosphonio) acetyl] amino]-1-piperidinyloxy, monochloride, monohydrate), a mitochondria-specific antioxidant, against cardiac and neurological complications following stroke. The objective is to assess whether MitoTEMPO can be utilized as a protective agent for individuals with a high risk of stroke.

MATERIALS AND METHODS

Seventeen-week-old male Wistar Albino rats were randomly assigned to three groups: SHAM, ischemia-reperfusion and MitoTEMPO + ischemia-reperfusion (MitoTEMPO injection 0.7 mg/kg/day for 14 days). The SHAM group underwent a sham operation, while the ischemia-reperfusion group underwent 1-h middle cerebral artery occlusion followed by three days of reperfusion. Afterwards, noninvasive thoracic electrical bioimpedance and electrocardiography measurements were taken, and sample collection was performed for histological and biochemical examinations.

RESULTS

Our thoracic electrical bioimpedance and electrocardiography findings demonstrated that MitoTEMPO exhibited a protective effect on most parameters affected by ischemia-reperfusion compared to the SHAM group. Furthermore, our biochemical and histological data revealed a significant protective effect of MitoTEMPO against oxidative damage.

CONCLUSIONS

The findings suggest that both ischemia-reperfusion-induced cardiovascular abnormalities and the protective effect of MitoTEMPO may involve G-protein coupled receptor-mediated signaling mechanisms. This study was conducted with limitations including a single gender, a uniform age group, a specific stroke model limited to middle cerebral artery, and pre-scheduled only one ischemia-reperfusion period. In future studies, addressing these limitations may enable the implementation of preventive measures for individuals at high risk of stroke.

Luteolin alleviates cerebral ischemia/reperfusion injury by regulating cell pyroptosis

Objective

This study aimed to clarify the roles and underlying mechanisms of luteolin in the progression of cerebral ischemia/reperfusion injury (CIRI).

Methods

A mouse model of CIRI was established using the middle cerebral artery occlusion (MCAO) method, after which luteolin was administered. Subsequently, neuronal apoptosis and pyroptosis were measured and the brain tissues of each group were subjected to RNA sequencing.

Results

Luteolin alleviated MCAO-induced brain infarction, apoptosis, and pyroptosis. RNA sequencing identified 3,379, 2,777, and 3,933 differentially expressed genes (DEGs) in the MCAO vs sham, MCAO vs MCAO + luteolin, and MCAO + luteolin vs sham groups, respectively. The identified DEGs showed enrichment in multiple processes, including pattern specification, forebrain development, anion transport, leukocyte migration, regulation of cell-cell adhesion, and positive regulation of the response to external stimuli, as well as the calcium, PI3K-AKT, JAK-STAT, NF-kappa B, IL-17, cAMP, cGMP-PKG, and Wnt signaling pathways. In addition, Ccl2 and Angpt2 interacted more with the other top 30 DEGs with high interaction weights. Finally, RT-qPCR results showed that MCAO induction significantly up-regulated the expression of Stoml3, Eomes, and Ms4a15 and down-regulated Nms, Ttr, and Avpr1a; however, luteolin could partially reverse the expression caused by MCAO.

Conclusion

Luteolin can alleviate brain infarction, apoptosis, and pyroptosis in CIRI, and may improve MCAO-induced CIRI by targeting the identified DEGs and their enriched pathways.

Gallic acid pretreatment mitigates parathyroid ischemia-reperfusion injury through signaling pathway modulation

Thyroid surgery often results in ischemia-reperfusion injury (IRI) to the parathyroid glands, yet the mechanisms underlying this and how to ameliorate IRI remain incompletely explored. Our study identifies a polyphenolic herbal extract-gallic acid (GA)-with antioxidative properties against IRI. Through flow cytometry and CCK8 assays, we investigate the protective effects of GA pretreatment on a parathyroid IRI model and decode its potential mechanisms via RNA-seq and bioinformatics analysis. Results reveal increased apoptosis, pronounced G1 phase arrest, and significantly reduced cell proliferation in the hypoxia/reoxygenation group compared to the hypoxia group, which GA pretreatment mitigates. RNA-seq and bioinformatics analysis indicate GA's modulation of various signaling pathways, including IL-17, AMPK, MAPK, transient receptor potential channels, cAMP, and Rap1. In summary, GA pretreatment demonstrates potential in protecting parathyroid cells from IRI by influencing various genes and signaling pathways. These findings offer a promising therapeutic strategy for hypoparathyroidism treatment.

Overexpression of olfactory receptor 78 ameliorates brain injury in cerebral ischaemia-reperfusion rats by activating Prkaca-mediated cAMP/PKA-MAPK pathway

Ischemic stroke is one of the main causes of disability and death. However, recanalization of occluded cerebral arteries is effective only within a very narrow time window. Therefore, it is particularly important to find neuroprotective biological targets for cerebral artery recanalization. Here, gene expression profiles of datasets GSE160500 and GSE97537 were downloaded from the GEO database, which were related to ischemic stroke in rats. Olfactory receptor 78 (Olfr78) was screened, and which highly associated with Calcium signalling pathway and MAPK pathway. Interacting protein of Olfr78, Prkaca, was predicted by STRING, and their interaction was validated by Co-IP analysis. Then, a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a neuronal cell model stimulated by oxygen-glucose deprivation/reoxygenation (OGD/R) were constructed, and the results showed that expression of Olfr78 and Prkaca was downregulated in MCAO rats and OGD/R-stimulated neurons. Overexpression of Olfr78 or Prkaca inhibited the secretion of inflammatory factors, Ca2+ overload, and OGD/R-induced neuronal apoptosis. Moreover, Overexpression of Prkaca increased protein levels of cAMP, PKA and phosphorylated p38 in OGD/R-stimulated neurons, while SB203580, a p38 inhibitor, treatment inhibited activation of the cAMP/PKA-MAPK pathway and counteracted the effect of Olfr78 overexpression on improvement of neuronal functions. Meanwhile, overexpression of Olfr78 or Prkaca markedly inhibited neuronal apoptosis and improved brain injury in MCAO/R rats. In conclusion, overexpression of Olfr78 inhibited Ca2+ overload and reduced neuronal apoptosis in MCAO/R rats by promoting Prkaca-mediated activation of the cAMP/PKA-MAPK pathway, thereby improving brain injury in cerebral ischaemia-reperfusion.

Compound musk injection in the treatment of ischemic stroke: A network analysis of the mechanism of action

BACKGROUND

Ischemic stroke (IS) is affected by a wide range of factors and has certain treatment limitations. Studies have reported that compound musk injection (CMI) is effective in the treatment of IS, however, its mechanism of action is still unclear.

METHODS

The main active ingredients in CMI were retrieved from HERB, TCMSP and BATMAN databases, and the relevant targets were predicted by Swiss Target Prediction platform. MalaCards, OMIM, DrugBank, DisGeNET, Genecards and TTD databases were used to obtain the genes related to IS. The intersection of drugs and disease targets was used to construct protein-protein interaction networks, and gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed. AutoDock Vina software was used for molecular docking, and cell experiments were conducted to verify the results. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression level of relative mRNA in cells.

RESULTS

Network analysis and molecular docking results showed that the key targets of CMI in the treatment of IS were SRC, TP53, PIK3R1, MAPK3, PIK3CA, MAPK1, etc. KEGG pathway enrichment analysis mainly involved PI3K/Akt signaling pathway, Rap1 signaling pathway and MAPK signaling pathway. The molecular docking results all showed that the key ingredients were strong binding activity with the key targets. The quantitative RT-PCR results indicated that CMI may increase the expression of PIK3CA, MAPK3 mRNA and decrease the expression of SRC mRNA.

CONCLUSIONS

CMI can treat IS by regulating pathways and targets related to inflammatory response and apoptosis in a multi-component manner.

Solasonine ameliorates cerebral ischemia-reperfusion injury via suppressing TLR4/MyD88/NF-κB pathway and activating AMPK/Nrf2/HO-1 pathway

Solasonine (SS), the main active ingredient of Solanum nigrum L., has been reported to possess a variety of pharmacological properties. A recent study demonstrated a neuroprotective effect of SS in a mouse nerve injury model. However, its protective effects on cerebral ischemia/reperfusion injury (CIRI) remain to be elucidated. We investigated herein the in vitro and in vivo neuroprotective effects of SS. Primary hippocampal neurons were exposed to oxygen and glucose deprivation/reoxygenation (OGD/R) to construct an in vitro model while rats were treated with middle cerebral artery occlusion/reperfusion (MCAO/R) to establish an in vivo CIRI model. The results showed that SS reduced OGD/R-induced inflammatory responses of neurons by blocking secretion of TNF-α, IL-1β and IL-6. Moreover, SS ameliorated OGD/R-induced oxidative stress in neurons by decreasing the level of ROS and MDA and increasing the activity of SOD and GPx. We also found that SS protected neurons from OGD/R-induced apoptosis by down-regulating bax and cleaved caspase-3 and up-regulating bcl-2. The in vivo results revealed that SS administration reduced the infarct volume and alleviated the neurological deficit of MCAO/R rats as well as diminished neuronal damages in these rats. Our investigation on the underlying mechanisms indicated that the neuroprotective effect of SS on CIRI may be associated with the TLR4/MyD88/NF-κB and AMPK/Nrf2/HO-1 pathways. Taken together, these findings demonstrate that SS ameliorates CIRI via suppressing TLR4/MyD88/NF-κB pathway and activating AMPK/Nrf2/HO-1 pathway.

PFT-α protects the blood-brain barrier through the Wnt/β-catenin pathway after acute ischemic stroke

The dysfunction of blood-brain barrier (BBB) plays a pivotal role in brain injury and subsequent neurological deficits of ischemic stroke. The current study aimed to examine the potential correlation between p53 inhibition and the neuroprotective effect of on the BBB. Rat middle cerebral artery occlusion and reperfusion model (MCAO/R) and oxygen-glucose deprivation/re-oxygenation model (OGD/R) were employed to simulate cerebral ischemia-reperfusion (CI/R) injury occurrence in vivo and in vitro. mNSS and TTC staining were applied to evaluate neurological deficits and brain infarct volumes. Evans blue (EB) staining was carried out to examine the permeability of BBB. RT-qPCR and Western blot to examine the mRNA and protein levels. Cell viabilities were detected by CCK-8. Flow cytometry and ELISA assay were employed to examine apoptosis and neuroinflammation levels. TEER value and sodium fluorescein were carried out to explore the permeability of HBMEC cells. PFT-α inhibited P53 and promoted the expression of β-catenin and cyclin D1, which were reversed by DKK1. PFT-α inhibited neurological deficits, brain infarct volume, neuroinflammation, apoptosis, and BBB integrity than the MCAO/R rats; however, this inhibition was reversed by DKK1. PFT-α promoted OGD/R-induced cell viability in NSCs, and suppressed inflammation and apoptosis, but DKK1 weakened the effect of PFT-α. PFT-α increased OGD/R-induced TEER values in cerebrovascular endothelial cells, inhibited sodium fluorescein permeability, and increased the mRNA levels of tight junction protein, but they were all attenuated by DKK1. PFT-α protects the BBB after acute ischemic stroke via the Wnt/β-catenin pathway, which in turn improves neurological function.

Malignant hyperthermia as a rare complication of local lidocaine injection: A case report

BACKGROUND

Malignant hyperthermia (MH) is a hypermetabolic disorder of skeletal muscles triggered by exposure to volatile anesthetics and depolarizing muscular relaxants. It manifests with clinical presentations such as tachycardia, muscle rigidity, hyperpyrexia, and rhabdomyolysis in genetically predisposed individuals with ryanodine receptor or calcium voltage-gated channel subunit alpha1 S mutations. Local anesthetics, such as lidocaine, are generally considered safe; however, complications can arise, albeit rarely. Lidocaine administration has been reported to induce hypermetabolic reactions resembling MH in susceptible individuals. The exact mechanism by which lidocaine might trigger MH is not fully understood. Although some mechanisms are postulated, further research is needed for a better understanding of this.

CASE SUMMARY

We present the case of MH in a 43-year-old male patient with an unknown genetic predisposition following a lidocaine injection during a dental procedure. This case serves as a reminder that while the occurrence of lidocaine-induced MH is rare, lidocaine can still trigger this life-threatening condition. Therefore, caution should be exercised when administering lidocaine to individuals who may be susceptible to MH. It is important to note that prompt intervention played a crucial role in managing the patient’s symptoms. Upon recognizing the early signs of MH, aggressive measures were initiated, including vigorous intravenous normal saline administration and lorazepam. Due to the effectiveness of these interventions, the administration of dantrolene sodium, a specific antidote for MH, was deferred.

CONCLUSION

This case highlighted the significance of vigilant monitoring and swift action in mitigating the detrimental effects of lidocaine-induced MH. Caution should be exercised when administering lidocaine to individuals who may be predisposed to MH. It is very important to be aware and vigilant of the signs and symptoms of MH as early recognition and treatment intervention are important to prevent serious complications to decrease mortality.

Prophylactic effect of intravenous lidocaine against cognitive deficit after cardiac surgery: A PRISMA-compliant meta-analysis and trial sequential analysis

BACKGROUND

This study aimed at providing an updated evidence of the association between intraoperative lidocaine and risk of postcardiac surgery cognitive deficit.

METHODS

Randomized clinical trials (RCTs) investigating effects of intravenous lidocaine against cognitive deficit in adults undergoing cardiac surgeries were retrieved from the EMBASE, MEDLINE, Google scholar, and Cochrane controlled trials register databases from inception till May 2021. Risk of cognitive deficit was the primary endpoint, while secondary endpoints were length of stay (LOS) in intensive care unit/hospital. Impact of individual studies and cumulative evidence reliability were evaluated with sensitivity analyses and trial sequential analysis, respectively.

RESULTS

Six RCTs involving 963 patients published from 1999 to 2019 were included. In early postoperative period (i.e., 2 weeks), the use of intravenous lidocaine (overall incidence = 14.8%) was associated with a lower risk of cognitive deficit compared to that with placebo (overall incidence = 33.1%) (relative risk = 0.49, 95% confidence interval: 0.32-0.75). However, sensitivity analysis and trial sequential analysis signified insufficient evidence to arrive at a firm conclusion. In the late postoperative period (i.e., 6-10 weeks), perioperative intravenous lidocaine (overall incidence = 37.9%) did not reduce the risk of cognitive deficit (relative risk = 0.99, 95% confidence interval: 0.84) compared to the placebo (overall incidence = 38.6%). Intravenous lidocaine was associated with a shortened LOS in intensive care unit/hospital with weak evidence.

CONCLUSION

Our results indicated a prophylactic effect of intravenous lidocaine against cognitive deficit only at the early postoperative period despite insufficient evidence. Further large-scale studies are warranted to assess its use for the prevention of cognitive deficit and enhancement of recovery (e.g., LOS).

Bioinformatic analysis of circular RNA expression profiles in a rat lumbosacral spinal root avulsion model

Lumbosacral spinal root avulsion (LSRA) is a severe nerve injury that results in devastating dysfunction in the lower limb. Circular ribonucleic acids (circRNAs) have been reported to be implicated in a variety of diseases. However, the role of circRNAs in LSRA remains unclear. Here, we performed RNA sequencing (RNA-seq) to determine circRNA expression profiles in a rat LSRA model and further investigated their potential functions and the underlying mechanisms by bioinformatic analyses and in vitro experiments. In all, 1708 circRNAs were found to be differentially expressed in spinal cord tissues after LSRA (|fold change| ≥ 2 and p < 0.05), with 591 up-regulated 1117 down-regulated. Meanwhile, 2263 mRNAs were also indentified to be differentially expressed, of which 1471 were upregulated and 792 were downregulated. Eight randomly selected circRNAs and mRNA were successfully verified to be consistent the RNA-seq results by quantitative real-time polymerase chain reaction. Functional analyses based on gene ontology and Kyoto Encyclopedia of Genes and Genomes predicted the potential roles of differentially expressed circRNAs and mRNAs in LSRA, and circRNA/miRNA/mRNA interaction networks revealed that circRNA_7025, a down-regulated circRNA in LSRA, was targeted by two neuronal apoptosis-related miRNAs, rno-miR-1224 and rno-miR-326-5p. Further in vitro experiments revealed that circRNA_7025 protected against oxygen-glucose deprivation induced neuronal apoptosis via the circRNA_7025/miR-1224/miR-326-5p axis. In summary, our results revealed circRNA expression profiles and their potential functions in LSRA. These findings improve our understanding of the pathogenic mechanisms involved in LSRA and might enable us to identify new molecular targets for LSRA.

Hypoxia- and Inflammation-Related Transcription Factor SP3 May Be Involved in Platelet Activation and Inflammation in Intracranial Hemorrhage

The purpose of this study was to identify the biomarkers implicated in the development of intracranial hemorrhage (ICH) and potential regulatory pathways. In the transcriptomic data for patients with ICH, we identified DEmiRNAs and DEmRNAs related to hypoxia, inflammation, and their transcription factors (TFs). An ICH-based miRNA-TF-mRNA regulatory network was thus constructed, and four biomarkers (TIMP1, PLAUR, DDIT3, and CD40) were screened for their association with inflammation or hypoxia by machine learning. Following this, SP3 was found to be a transcription factor involved in hypoxia and inflammation, which regulates TIMP1 and PLAUR. From the constructed miRNA-TF-mRNA regulatory network, we identified three axes, hsa-miR-940/RUNX1/TIMP1, hsa-miR-571/SP3/TIMP1, and hsa-miR-571/SP3/PLAUR, which may be involved in the development of ICH. Upregulated TIMP1 and PLAUR were validated in an independent clinical cohort 3 days after ICH onset. According to Gene Set Enrichment Analysis (GSEA), SP3 was discovered to be important in interleukin signaling and platelet activation for hemostasis. Transcription factor SP3 associated with hypoxia or inflammation plays an important role in development of ICH. This study provides potential targets for monitoring the severity of inflammation and hypoxia in patients with ICH.

miR-542-3p-Targeted PDE4D Regulates cAMP/PKA Signaling Pathway and Improves Cardiomyocyte Injury

Objective

To investigate the protective effect of miR-542-3p on cardiomyocyte injury and related mechanisms.

Methods

A cardiomyocyte hypoxia/reoxygenation model was established. The expression levels of miR-542-3p and PDE4D were detected using qRT-PCR; the luciferase reporter assay system was used to detect the targeting relationship between miR-542-3p and PDE4D; overexpressing miR-542-3p was transfected into cardiomyocytes, and ROS release was detected by immunofluorescence while cellular apoptosis was detected by TUNEL; and the western blot assay was applied to detect the expression of PDE4D, phosphorylated protein kinase A (p-PKA), and phosphorylated cyclic adenosine monophosphate (cAMP) response element-binding protein (p-CREB).

Results

Compared with the control group, the miR-542-3p expression level was decreased and the PDE4D expression level was increased in the cardiomyocyte hypoxia/reoxygenation model group. The dual-luciferase reporter assay system confirmed that miR-542-3p could target and regulate PDE4D; the transfection with cardiomyocytes using the overexpressing miR-542-3p could downregulate PDE4D expression, attenuate ROS release during cardiomyocyte injury, and reduce cellular apoptosis rate, while upregulating the expression of p-PKA and p-CREB.

Conclusion

The miR-542-3p can negatively regulate PDE4D protein expression and attenuate cardiomyocyte injury through a mechanism related to the activation of the cAMP/PKA signaling pathway.

Lidocaine attenuates hypoxia/reoxygenation‑induced inflammation, apoptosis and ferroptosis in lung epithelial cells by regulating the p38 MAPK pathway

Lung ischemia-reperfusion (I/R) injury poses a serious threat to human health, worldwide. The current study aimed to determine the role of lidocaine in A549 cells, in addition to the involvement of the p38 MAPK pathway. Oxygen deprivation/reoxygenation-induced A549 cells were utilized to simulate I/R injury in vitro. Cell viability and apoptosis were detected using MTT and TUNEL assays, respectively. The levels of IL-6, IL-8, TNF-α, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase, iron and reactive oxygen species (ROS) were measured using corresponding commercial kits. The corresponding protein expression levels were also measured using western blotting. Moreover, a monolayer cell paracellular permeability assay was performed to determine the permeability of A549 cells. The results demonstrated that, whilst lidocaine had no influence on untreated A549 cells, it significantly increased the viability of hypoxia/reoxygenation (H/R)-induced A549 cells. A549 cell apoptosis and the release of inflammatory cytokines in the H/R group were decreased after the addition of lidocaine. When compared with the H/R group, increased MDA level and decreased SOD level were observed in H/R-induced A549 cells following lidocaine treatment. In addition, the permeability of H/R-induced A549 cells was markedly decreased following lidocaine treatment. Compared with the H/R group, the expression levels of tight junction and ferroptosis-related proteins were significantly upregulated by lidocaine, whereas the expression of transferrin was downregulated. However, p79350, an agonist of p38, reversed the effects of lidocaine on H/R-induced A549 cells. In conclusion, lidocaine exerted a protective role in HR-induced lung epithelial cell injury, which may serve as a potential agent for the treatment of patients with lung I/R injury.

Phosphodiesterase inhibitor, Vinpocetine, guards against doxorubicin induced cardiotoxicity via modulation of HIF/VEGF and cGMP/cAMP/SIRT signaling pathways

Purpose: Doxorubicin (DOX) is a widely used chemotherapeutic agent complicated with cardiotoxic adverse effects. Up till now, there are no researches discussing the role of vinpocetine (VIN) in DOX cardiotoxicity. Thus, the aim of our work was to study this effect and explore the different involved mechanisms.

Methods:

50 male Wistar albino rats were subjected to DOX toxicity via administration of single i.p. Dose (15 mg/kg) on the 4th day with or without co-administration of VIN (10, 20, 30 mg/kg/day) orally for 5 days.

Results:

Our data revealed that VIN succeeded in protecting the heart against DOX induced damage as manifested by significant decrease of cardiac enzymes, hypoxia inducible factor alpha (HIF-1α), vascular endothelial growth factor-A (VEGF-A), tissue malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α) and caspase3 levels. Furthermore, VIN given group showed marked improvement of the histopathological changes of cardiac injury, total antioxidant capacity (TAC), elevation of reduced glutathione (GSH), cyclic guanosine monophosphate (cGMP), cyclic adenosine monophosphate (cAMP) and sirtuin-1 (SIRT-1).

Conclusion:

We concluded that VIN could ameliorate DOX induced cardiac damage and this effect may be attributed to modulation of HIF/VEGF signaling pathway, up-regulation of cGMP/cAMP/SIRT pathway, inhibition of phosphodiesterase enzyme, besides its anti-apoptotic, anti-inflammatory, and anti-oxidant properties.

Pharmacological prevention of renal ischemia-reperfusion injury in a rat model

INTRODUCTION

Renal ischemia-reperfusion injury (IRI) can lead to significant morbidity and mortality. It remains a leading cause of acute kidney injury and is therefore an important issue in trauma and renal transplant surgery. Various pharmaceutical agents have been used in an attempt to dampen the harmful effects of IRI but few have been shown to be useful clinically. Riluzole, Lidocaine and Lamotrigine have been demonstrated to show anti-ischaemic properties in other organs; however, their use has not been tested in the kidneys. We investigated Riluzole, Lidocaine and Lamotrigine for their preventive effects of renal IRI using a rat model.

METHODS

Winstar rats (n = 48) were divided into four groups (n = 12 per group)-three treatment groups and one control group. Riluzole, Lidocaine and Lamotrigine were given prior to renal ischemia only (IO) or IRI. The degree of ischemia was measured by glutathione levels and a TUNEL assay was used to measure DNA fragmentation.

RESULTS

Riluzole, Lidocaine and Lamotrigine pre-treatment each resulted in statistically higher glutathione levels compared to controls (P = 0.002; P = 0.007 and P = 0.005, respectively). Riluzole and Lidocaine were also effective at preventing depletion of glutathione following IO (P = 0.007 and P = 0.014 respectively), while Lamotrigine was ineffective in IO (P = 0.71). The degree of DNA fragmentation seen on the TUNEL assay was markedly reduced in all three-drug groups in both IO and IRI.

DISCUSSION

Riluzole, Lidocaine and Lamotrigine all have anti-ischaemic effects in the rat kidney and can have potential therapeutic implications.

Potentially Functional microRNA-mRNA Regulatory Networks in Intestinal Ischemia-Reperfusion Injury: A Bioinformatics Analysis

Background

Intestinal ischemia-reperfusion (II/R) injury is a common clinical complication associated with high mortality, for which microRNA (miRNA) drives potentially its pathophysiological progression. MiRNAs regulate different messenger RNAs (mRNAs). However, the regulatory network between miRNAs and mRNAs in intestinal ischemia-reperfusion injury is elusive.

Methods

We analyzed the different expression of mRNAs and miRNAs in intestinal tissues from patients from three groups (arterial group (group A), venous group (group V), control group (group C)). Common differentially expressed (Co-DE) miRNAs and differentially expressed mRNAs were acquired via concerned analyses among the three groups. Co-DE mRNAs were shared parts of target mRNAs and differentially expression mRNAs. Cytoscape was employed to construct the regulatory network between miRNAs and mRNAs. Gene Ontology (GO) analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway depicted the functions and potential pathway associated with Co-DE mRNAs. Using the STRING and Cytoscape, we found critical mRNAs in the protein–protein interaction (PPI) network.

Results

The miRNA-mRNA network comprised 8 Co-DE miRNAs and 140 Co-DE mRNAs. Of note, 140 Co-DE mRNAs were targets of these 8 miRNAs, and their roles were established through the functional exploration via GO analysis and KEGG analysis. PPI network and Cytoscape revealed COL1A2, THY1, IL10, MMP2, SERPINH1, COL3A1, COL14A1, and P4HA1 as the top 8 key mRNAs.

Conclusion

This study has demonstrated a miRNA-mRNA regulatory network in intestinal ischemia-reperfusion injury, and explored the key mRNAs and their potential functions. These findings could provide new insight into prognostic markers and therapeutic targets for patients with intestinal ischemia-reperfusion injury in clinical practice.

Tongmai Yangxin pill reduces myocardial No-reflow via endothelium-dependent NO-cGMP signaling by activation of the cAMP/PKA pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The Tongmai Yangxin pill (TMYX) is derived from the Zhigancao decoction recorded in Shang han lun by Zhang Zhongjing during the Han dynasty. TMYX is used for the clinical treatment of chest pain, heartache, and qi-yin-deficiency coronary heart disease. Previous studies have confirmed that TMYX can improve vascular endothelial function in patients with coronary heart disease by upregulating nitric oxide activity and then regulating vascular tension. Whether TMYX can further improve myocardial NR by upregulating NO activity and then dilating blood vessels remains unclear.

AIM OF THE STUDY

This study aimed to reveal whether TMYX can further improve myocardial NR by upregulating NO activity and then dilating blood vessels. The underlying cAMP/PKA and NO-cGMP signaling pathway-dependent mechanism is also explored.

MATERIALS AND METHODS

The left anterior descending coronary arteries of healthy adult male SD rats were ligated to establish the NR model. TMYX (4.0 g/kg) was orally administered throughout the experiment. Cardiac function was measured through echocardiography. Thioflavin S, Evans Blue, and TTC staining were used to evaluate the NR and ischemic areas. Pathological changes in the myocardium were assessed by hematoxylin-eosin staining. An automated biochemical analyzer and kit were used to detect the activities of myocardial enzymes and myocardial oxidants, including CK, CK-MB, LDH, reactive oxygen species, superoxide dismutase, malonaldehyde, and NO. The expression levels of genes and proteins related to the cAMP/PKA and NO/cGMP signaling pathways were detected via real-time fluorescence quantitative PCR and Western blot analysis, respectively. A microvascular tension sensor was used to detect coronary artery diastolic function in vitro.

RESULTS

TMYX elevated the EF, FS, LVOT peak, LVPWd and LVPWs values, decreased the LVIDd, LVIDs, LV-mass, IVSd, and LV Vols values, demonstrating cardio-protective effects, and reduced the NR and ischemic areas. Pathological staining showed that TMYX could significantly reduce inflammatory cell number and interstitial edema. The activities of CK, LDH, and MDA were reduced, NO activity was increased, and oxidative stress was suppressed after treatment with TMYX. TMYX not only enhanced the expression of Gs-α, AC, PKA, and eNOS but also increased the expression of sGC and PKG. Furthermore, TMYX treatment significantly decreased ROCK expression. We further showed that TMYX (25-200 mg/mL) relaxed isolated coronary microvessels.

CONCLUSIONS

TMYX attenuates myocardial NR after ischemia and reperfusion by activating the cAMP/PKA and NO/cGMP signaling pathways, further upregulating NO activity and relaxing coronary microvessels.

[Protective effect of iridoid glycosides of radix scrophulariae on endoplasmic reticulum stress induced by oxygen-glucose deprivation and reperfusion in vitro model]

OBJECTIVE

To investigate the regulatory effect of iridoid glycoside of radix scrophulariae (IGRS) on endoplasmic reticulum stress induced by oxygen-glucose deprivation and reperfusion in vitro model.

METHODS

Rat pheochromocytoma PC12 cells were pretreated with IGRS (50, 100, 200 μg/mL) for 24h, and the in vitro model of oxygen-glucose deprivation/reoxygenation (OGD/R) was applied. The cell viability was determined by MTT and lactate dehydrogenase (LDH) assay. The apoptotic rate was detected by flow cytometry. The expression of B-cell lymphoma-2 (Bcl-2), Bcl-2 related X protein (Bax), C/EBP homologous protein (CHOP), caspase-12 protein, and glucose-regulated protein-78(GRP78)were detected by Western blotting. The mRNA expression levels of sarco/endoplasmic reticulum Ca2+-ATPase2 (SERCA2), 1, 4, 5-triphosphate inositol receptor 1 (IP3R1), and ryanodine receptor 2 (RyR2)were detected by real-time RT-PCR. Free Ca2+ concentration [Ca2+]i was determined by using laser scanning confocal microscopy.

RESULTS

The damage caused by OGD/R to PC12 cells was significantly reduced by IGRS, with significant effect on increasing survival rate and reducing LDH release (all P<0.01). The expression of GRP78, CHOP, Bax, and caspase-12 were down-regulated (all P<0.01), and the expression of Bcl-2 and Bcl-2/Bax ratio was up-regulated (all P<0.01); IGRS increased the expression of SERCA2 mRNA in PC12 cells after OGD/R injury (P<0.01), decreased [Ca2+]i and down-regulated the expression of RyR2 mRNA and IP3R1 mRNA.

CONCLUSIONS

IGRS has neuroprotective effect, which may alleviate cerebral ischemia-reperfusion injury by regulating SERCA2, maintaining calcium balance, and inhibiting endoplasmic reticulum stress-mediated apoptosis.