Ginsenoside Rg1 attenuates cardiomyocyte apoptosis and inflammation via the TLR4/NF-kB/NLRP3 pathway

Ginsenoside Rg1 as a promising adjuvant agent for enhancing the anti-cancer functions of granulocytes inhibited by noradrenaline

Introduction

In recent years, numerous studies have confirmed that chronic stress is closely related to the development of cancer. Our previous research showed that high levels of stress hormones secreted in the body during chronic stress could inhibit the cancer-killing activity of granulocytes, which could further promote the development of cancer. Therefore, reversing the immunosuppressive effect of stress hormones on granulocytes is an urgent problem in clinical cancer treatment. Here, we selected noradrenaline (NA) as a representative stress hormone.

Methods and results

After screening many traditional Chinese herbal medicine active ingredients, a promising compound, ginsenoside Rg1, attracted our attention. We verified the immunoprotective effect of ginsenoside Rg1 on granulocytes in vitro and ex vivo, and attempted to understand its potential immunoprotective mechanism. We confirmed the immunoprotective effect of ginsenoside Rg1 on granulocytes using cell and animal experiments. Cell counting kit-8 (CCK-8) and ex vivo experiments were performed to investigate the immunoprotective effects of ginsenoside Rg1 on the anti-cancer function of granulocytes inhibited by NA. Transcriptome sequencing analysis and qRT-PCR showed that NA elevated the mRNA expression of ARG2, MMP1, S100A4, and RAPSN in granulocytes, thereby reducing the anti-cancer function of granulocytes. In contrast, ginsenoside Rg1 downregulated the mRNA expression of ARG2, MMP1, S100A4, and RAPSN, and upregulated the mRNA expression of LAMC2, DSC2, KRT6A, and FOSB, thereby enhancing the anti-cancer function of granulocytes inhibited by NA. Transwell cell migration experiments were performed to verify that ginsenoside Rg1 significantly enhanced the migration capability of granulocytes inhibited by NA. Tumor-bearing model mice were used to verify the significant immunoprotective effects in vivo. Finally, CCK-8 and hematoxylin and eosin staining experiments indicated that ginsenoside Rg1 exhibited high biosafety in vitro and in vivo.

Discussion

In future clinical treatments, ginsenoside Rg1 may be used as an adjuvant agent for cancer treatment to alleviate chronic stress-induced adverse events in cancer patients.

Traditional Chinese medicine for treatment of sepsis and related multi-organ injury

Sepsis is a common but critical illness in patients admitted to the intensive care unit and is associated with high mortality. Although there are many treatments for sepsis, specific and effective therapies are still lacking. For over 2,000 years, traditional Chinese medicine (TCM) has played a vital role in the treatment of infectious diseases in Eastern countries. Both anecdotal and scientific evidence show that diverse TCM preparations alleviate organ dysfunction caused by sepsis by inhibiting the inflammatory response, reducing oxidative stress, boosting immunity, and maintaining cellular homeostasis. This review reports on the efficacy and mechanism of action of various TCM compounds, herbal monomer extracts, and acupuncture, on the treatment of sepsis and related multi-organ injury. We hope that this information would be helpful to better understand the theoretical basis and empirical support for TCM in the treatment of sepsis.

Roles of ginsenosides in sepsis

The herbal medication Panax ginseng Meyer has widespread use in China, Korea, and other parts of the world. The main constituents of ginseng are ginsenosides, which include over 30 different triterpene saponins. It has been found that ginsenosides and their metabolites including Rg1, compound K, Rb1, Re, Rg3, and Rg5 exert anti-inflammatory activities by binding to the glucocorticoid receptor, modulating inflammation-related signaling, including NF-κB and MAPK signaling, and reducing levels of pro-inflammatory cytokines. Here, we review the recent literature on the molecular actions of ginsenosides in sepsis, suggesting ways in which they may be used to prevent and treat the disease.

Ginsenoside Rg1 Improves Inflammation and Autophagy of the Pancreas and Spleen in Streptozotocin-Induced Type 1 Diabetic Mice

BACKGROUND

Ginsenoside Rg1 (Rg1) is one of the key bioactive components of the precious Traditional Chinese Medicine that has been used to treat diabetes in China. Ginsenosides have been reported to protect diabetics from tissue damage, inflammation, and insulin resistance. Type 1 diabetes (T1D) is an organ-specific autoimmune disease that occurred frequently among adolescents over the world, its development was related to inflammation and β-cells immunodeficiency. The aim of this study is to explore the biological mechanism of Rg1 on inflammation and autophagy of β-cells in T1D and its therapeutic potential.

METHODS

The model of T1D mice was established by injecting Streptozotocin (STZ) (55 mg/kg) or citric acids once a day for 5 days and from the fourth day of injection, mice were administered with Rg1 (20 mg/kg) or saline by gavage once a day for 12 days. Hematoxylin-eosin staining, immunofluorescence, ELISA, quantitative real-time PCR, and Western blot were used to observe the histopathological changes, inflammatory factor levels, and autophagy markers after administration of ginsenoside Rg1.

RESULTS

Compared to the T1D mice, Rg1 improved the weight (p < 0.05) and blood glucose (p < 0.01) of mice, advanced the injury and apoptosis of β-cells in islets (p < 0.01), and markedly inhibited the protein expression degrees of CD45, CXCL16, ox-LDL, and TF in the pancreas and spleens (p < 0.01), also activated the degrees of insulin in serum (p < 0.01). Besides, in T1D mice' pancreas and spleen, Rg1 markedly repressed the IL-1β, TNF-α, and NOS2 mRNA levels (p < 0.05 or p < 0.01), inhibited the CXCL16, NF-κB, and TF proteins (p < 0.05 or p < 0.01), while elevating the ratio of LC3 II/I (p < 0.01) and P62 (p < 0.05) protein level.

CONCLUSIONS

This study proved that Rg1 protected mice against T1D possibly by improving islet injury and tissue inflammation, raising serum insulin, and tissue autophagy marker.

Inappropriate Activation of TLR4/NF-κB is a Cause of Heart Failure

Significance: Heart failure, a disease with extremely high incidence, is closely associated with inflammation and oxidative stress. The Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) pathway plays an important role in the occurrence and development of heart failure.

Recent advances: Previous studies have shown that TLR4/NF-κB causes heart failure by inducing oxidative stress and inflammation; damaging the endothelia; promoting fibrosis; and inducing myocardial hypertrophy, apoptosis, pyroptosis, and autophagy.

Critical issues: Understanding the pathogenesis of heart failure is essential for the treatment of this disease. In this review, we outline the mechanisms underlying TLR4/NF-κB pathway-mediated heart failure and discuss drugs that alleviate heart failure by regulating the TLR4/NF-κB pathway.

Future directions: During TLR4/NF-κB overactivation, interventions targeting specific receptor antagonists may effectively alleviate heart failure, thus providing a basis for the development of new anti-heart failure drugs.

Evaluating the effects of curcumin nanomicelles on clinical outcome and cellular immune responses in critically ill sepsis patients: A randomized, double-blind, and placebo-controlled trial

Introduction

In sepsis, the immune system is overreacting to infection, leading to organ dysfunction and death. The purpose of this study was to investigate the impacts of curcumin nanomicelles on clinical outcomes and cellular immune responses in critically ill sepsis patients.

Method

For 10 days, 40 patients in the intensive care units (ICU) were randomized between the nano curcumin (NC) and placebo groups in a randomized study. We evaluated serum levels of biochemical factors, inflammatory biomarkers, the mRNA expression levels of FOXP3, NLRP-3, IFN-γ, and NF-κp genes in the PBMCs, and clinical outcomes before the beginning of the supplementation and on days 5 and 10.

Results

NLR family pyrin domain containing 3 (NLRP3), interferon gamma (IFN-γ), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) mRNA expression levels significantly P = 0.014, P = 0.014, and P = 0.019, respectively) decreased, but forkhead box P3 (FOXP3) mRNA expression levels increased significantly (P = 0.008) in the NC group compared to the placebo group after 10 days. NC supplementation decreased serum levels of IL-22, IL-17, and high mobility group box 1 (HMGB1) (P < 0.05). Nevertheless, biochemical factors and nutritional status did not differ significantly (P > 0.05). NC supplementation resulted in decreased sequential organ failure assessment and multiple organ dysfunction syndromes scores, while it did not have significant impacts on length of stay in the ICU, systolic blood pressure, diastolic blood pressure, a saturation of oxygen (%), and respiratory rate (breaths/min) PaO2/FiO2 (p > 0.05).

Conclusion

For critically ill patients with sepsis, NC supplementation may be an effective therapeutic strategy. More randomized clinical trials involving longer follow-up periods and different doses are needed to achieve the best results.

The Protective Effect of Sheng Mai Yin on Diabetic Cardiomyopathy via NLRP3/Caspase-1 Pathway

Sheng Mai Yin (SMY) has therapeutic effects on myocardial infarction (MI), heart failure (HF), diabetic cardiomyopathy (DCM), and myocarditis. To study whether SMY can relieve pyroptosis and play a protective role in diabetic cardiomyopathy, a molecular docking technique was used to predict the possible mechanism of SMY against DCM. Then, a DCM rat model was induced by intraperitoneal injection of streptozotocin (STZ), divided into 5 groups: the DM group (model), SMY-L group (2.7 mL/kg SMY), SMY-M group (5.4 mL/kg SMY), SMY-H group (10.8 mL/kg SMY), and Met group (120 mg/kg metformin). Rats in the CTL group (control) and DM group were given normal saline. After 8 weeks, the levels of blood glucose, lipids, and myocardial enzymes were detected according to the kit instructions. Cardiac function was detected by echocardiography. HE and Masson were used to observing the pathological changes, collagen deposition, and collagen volume fraction (CVF). The apoptosis rate of cardiomyocytes was determined by Tunel. The IL-1β level was determined by ELISA and RT-PCR. The expressions of NLRP3, caspase-1, and GSDMD were measured using RT-PCR and Western blotting. The docking results suggested that SMY may act on NLRP3 and its downstream signal pathway. The in vivo results showed that SMY could reduce blood glucose and lipid levels, improve heart function, improve histopathological changes and myocardial enzymes, and alleviate cardiomyocyte apoptosis and myocardial fibrosis. SMY inhibited the mRNA and protein expressions of NLRP3, ASC, Caspase-1, and GSDMD and IL-1β production. SMY can reduce DCM by regulating the NLRP3/caspase-1 signaling pathway, providing a new research direction for the treatment of DCM.

Bioactive compounds modulating Toll-like 4 receptor (TLR4)-mediated inflammation: pathways involved and future perspectives

Chronic inflammation is associated with the development and progression of several noncommunicable diseases, such as diabetes, cardiovascular disease, chronic kidney disease, cancer, and nonalcoholic fatty liver disease. Evidence suggests that pattern recognition receptors that identify pathogen-associated molecular patterns and danger-associated molecular patterns are crucial in chronic inflammation. Among the pattern recognition receptors, Toll-like receptor 4 (TLR4) stimulates several inflammatory pathway agonists, such as nuclear factor-κB, interferon regulator factor 3, and nod-like receptor pyrin domain containing 3 pathways, which consequently trigger the expression of pro-inflammatory biomarkers, increasing the risk of noncommunicable disease development and progression. Studies have focused on the antagonistic potential of bioactive compounds, following the concept of food as a medicine, in which nutritional strategies may mitigate inflammation via TLR4 modulation. Thus, this review discusses preclinical evidence concerning bioactive compounds from fruit, vegetable, spice, and herb extracts (curcumin, resveratrol, catechin, cinnamaldehyde, emodin, ginsenosides, quercetin, allicin, and caffeine) that may regulate the TLR4 pathway and reduce the inflammatory response. Bioactive compounds can inhibit TLR4-mediated inflammation through gut microbiota modulation, improvement of intestinal permeability, inhibition of lipopolysaccharide-TLR4 binding, and decreasing TLR4 expression by modulation of microRNAs and antioxidant pathways. The responses directly mitigated inflammation, especially nuclear factor-κB activation and inflammatory cytokines release. These findings should be considered for further clinical studies on inflammation-mediated diseases.

Ginsenoside Rg1 Inhibits STAT3 Expression by miR-15b-5p to Attenuate Lung Injury in Mice with Type 2 Diabetes Mellitus-Associated Pulmonary Tuberculosis

Type 2 diabetes mellitus (T2DM) has been regarded as a critical risk factor for pulmonary tuberculosis (PTB). Ginsenoside Rg1 has been identified as a potential therapeutic agent for T2DM by suppressing the inflammatory response. However, the effect of Rg1 on T2DM-associated PTB has not been reported. In this study, we aimed to explore the function of Rg1 in the regulation of T2DM-associated PTB. We established a T2DM-associated PTB mouse model and found that the fibrosis of lung tissues was inhibited by Rg1 in T2DM-associated PTB mice. The lung injury of T2DM-associated PTB mice was repressed by Rg1. Moreover, the levels of IL-6, TNF-α, and IL-1β in the lung tissues and serum were decreased by Rg1 in T2DM-associated PTB mice. The treatment with Rg1 inhibited the levels of free fatty acid and enhanced the expression of miR-15b-5p in lung tissues of T2DM-associated PTB mice. MiR-15b-5p targeted and inhibited the STAT3 expression. The expression of STAT3 was downregulated by Rg1, while the inhibition of miR-15b-5p reversed the downregulation. The expression of miR-15b-5p was reduced, but the expression of STAT3 was upregulated in the lung tissues of T2DM-associated PTB mice. We validated that miR-15b-5p attenuated inflammation and lung injury in the T2DM-associated PTB mouse model. The overexpression of STAT3 or the suppression of miR-15b-5p restored lung fibrosis and injury inhibited by Rg1 in T2DM-associated PTB mice. Meanwhile, the Rg1-repressed levels of IL-6, TNF-α, and IL-1β were enhanced by the overexpression of STAT3 or the suppression of miR-15b-5p. In addition, the levels of free fatty acid repressed by Rg1 were reversed by STAT3 overexpression and miR-15b-5p inhibition. Thus, we conclude that ginsenoside Rg1 inhibits the STAT3 expression by miR-15b-5p to attenuate lung injury in mice with type 2 diabetes mellitus-associated pulmonary tuberculosis.

Adiponectin reduces apoptosis of diabetic cardiomyocytes by regulating miR-711/TLR4 axis

OBJECTIVE

To investigate the regulation of adiponectin/miR-711 on TLR4/NF-κB-mediated inflammatory response and diabetic cardiomyocyte apoptosis.

METHODS

Diabetes models were established using rats and H9c2 cardiomyocytes. qRT-PCR was used to detect adiponectin, miR-711, and TLR4. MTT, β-galactosidase staining, and flow cytometry were utilized to assess cell viability, senescence, and apoptosis, respectively. The colorimetric method was used to measure caspase-3 activity, DCFH-DA probes to detect ROS, and western blotting to determine the protein levels of Bax, Bcl-2, TLR4, and p-NF-κB p65. ELISA was performed to measure the levels of adiponectin, ICAM-1, MCP-1, and IL-1β. Dual-luciferase reporter system examined the targeting relationship between miR-711 and TLR4. H&E and TUNEL staining revealed myocardial structure and apoptosis, respectively.

RESULTS

Adiponectin and miR-711 were underexpressed and TLR4/NF-κB signaling pathway was activated in high glucose-treated H9c2 cells. High glucose treatment reduced viability, provoked inflammatory response, and accelerated senescence and apoptosis in H9c2 cells. miR-711 could bind TLR4 mRNA and inactivate TLR4/NF-κB signaling. Adiponectin treatment increased miR-711 expression and blocked TLR4/NF-κB signaling. Adiponectin/miR-711 reduced myocardial inflammation and apoptosis in diabetic rats.

CONCLUSION

Adiponectin inhibits inflammation and alleviates high glucose-induced cardiomyocyte apoptosis by blocking TLR4/NF-κB signaling pathway through miR-711.

Protective effect of ginsenoside Rh2 against Toxoplasma gondii infection-induced neuronal injury through binding TgCDPK1 and NLRP3 to inhibit microglial NLRP3 inflammasome signaling pathway

BACKGROUND

Toxoplasma gondii (T. gondii) is a neurotropic obligate intracellular parasite that can activate microglial and promote neuronal apoptosis, leading to central nervous system diseases. The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome signaling complex plays a key role in inducing neuroinflammation. Our previous studies have found that ginsenoside Rh2 (GRh2) inhibits T. gondii infection-induced microglial activation and neuroinflammation by downregulating the Toll-like receptor 4/nuclear factor-kappa B signaling pathway. However, whether GRh2 reduces T. gondii infection-induced neuronal injury through actions on microglial NLRP3 inflammasome signaling has not yet been clarified.

METHODS

In this study, we employed T. gondii RH strain to establish in vitro and in vivo infection models in BV2 microglia cell line and BALB/c mice. Molecular docking, localized surface plasmon resonance assay, quantitative competitive-PCR, ELISA, western blotting, flow cytometric analysis, and immunofluorescence were performed.

RESULTS

Our results showed that GRh2 alleviated neuropathological damage and neuronal apoptosis in cortical tissue of T. gondii-infected mice. GRh2 and CY-09 (an inhibitor of NLRP3) exhibited potent anti-T. gondii effects through binding T. gondii calcium-dependent protein kinase 1 (TgCDPK1). GRh2 decreased Iba-1 (a specific microglial marker) and NLRP3 inflammasome signaling pathway-related protein expression by binding NLRP3. Co-culture of microglia/primary cortical neurons revealed that T. gondii-induced microglial activation caused neuronal apoptosis, but GRh2 reduced this effect, consistent with the effects of CY-09.

CONCLUSION

Taken together, our results show that GRh2 has a protective effect against T. gondii infection-induced neuronal injury by binding TgCDPK1 and NLRP3 to inhibit NLRP3 inflammasome signaling pathway in microglia.

Ginsenoside Rg1 ameliorates apoptosis, senescence and oxidative stress in ox‑LDL‑induced vascular endothelial cells via the AMPK/SIRT3/p53 signaling pathway

Coronary heart disease (CHD) mainly refers to coronary atherosclerotic heart disease and its pathogenesis is complex. Ginsenoside Rg1 (Rg1) has a wide range of pharmacological activities, such as antitumor effects, enhancing immunity and exerting protective effects on the vascular system. In the present study, the effect of Rg1 on vascular endothelial cells in CHD was investigated. Oxidized low-density lipoprotein (ox-LDL) was used to induce human umbilical vein endothelial cells (HUVECs) and cells were treated with 1, 5 or 10 µM Rg1. Cell Counting Kit-8 assay, TUNEL staining, western blot analysis of apoptosis-related proteins and senescence-related proteins, senescence-associated β-galactosidase staining, ELISA and other techniques including related kits of oxidative stress markers were used to detect the viability, apoptosis, oxidative stress, inflammatory cytokines including IL-1β, IL-6 and TNF-α and senescence of ox-LDL-induced HUVECs induced by Rg1. Western blot analysis was used to detect the expression levels of the AMP-activated protein kinase (AMPK)/sirtuin 3 (SIRT3)/p53 signaling pathway-related proteins. In addition, the associated mechanism was further determined using the AMPK pathway inhibitor compound C (CC). Rg1 increased the viability, and inhibited the apoptosis, senescence, oxidative stress and inflammation of ox-LDL-induced HUVECs. Pretreatment with CC partially reversed the protective effect of Rg1 on ox-LDL-induced HUVECs. In conclusion, Rg1 ameliorated apoptosis, senescence and oxidative stress of ox-LDL-induced HUVECs, at least in part, via the AMPK/SIRT3/p53 signaling pathway.

The Chinese medicine babaodan suppresses LPS-induced sepsis by inhibiting NLRP3-mediated inflammasome activation

ETHNOPHARMACOLOGICAL RELEVANCE

BBD is a well-known traditional Chinese medicine widely used in clinic to treat viral hepatitis, cholecystitis, angiocholitis and urinary tract infection. According to traditional medicinal theory, BBD exerts the effects of "clearing and humid heat, activating blood and removing toxicity, curing jaundice and relieving pain", the signs of which are recognized as common symptoms of inflammation during infectious diseases in modern medicine.

AIM OF THE STUDY

To determine the therapeutic effect of BBD on bacterial endotoxin lipopolysaccharide (LPS) induced sepsis and to investigate the relevant pharmacological and molecular mechanisms of action whereby BBD mitigates inflammation.

MATERIALS AND METHODS

In vivo, a mouse sepsis model was induced by intraperitoneally injection of LPS; the BBD were formulated as drug suspension for intragastric administration. The survival rate, secretion of pro-inflammatory cytokines of IL-1β and TNF-α, and multiple organ injury of lung, liver and spleen were examined. In vitro, peritoneal macrophages (PMs) were stimulated with LPS plus ATP for NLRP3 inflammasome activation; polar gradient extractions of BBD from ultrapure water (sample 1) followed by 70% ethanol (sample 2) were added as interventions. In addition to detect the secretion of IL-1β and TNF-α, the activation of NF-κB, ASC-speck formation and ASC oligomerization were examined by western blotting and immunofluorescent stainning. Eventually, the extractions of BBD were applied for UPLC-QTOF-MS analyses; refer to the identified chemicals, the bioactive compounds in BBD with anti-NLRP3 inflammasome activities were discussed.

RESULTS

BBD improved the survival of sepsis mice accomplished with diminished inflammatory cytokines production and multiple organ injury. Mechanistically, BBD inhibited both the NF-κB pathway and the assembly of NLRP3 complex in PMs. There were 29 chemical compounds identified from sample 1 and 20 from sample 2. Both samples contained bile acids and saponins and sample 2 contained 2 extra chemicals in the category of bile acids.

CONCLUSIONS

BBD presents therapeutic role of endotoxin induced sepsis by inhibiting NLRP3-medaited inflammasome activation, which supports its traditional use for the treatment of infectious diseases. The bile acids and saponins are most likely related to the anti-NLRP3 inflammasome activation effect of BBD.

Ginsenoside Rg1 Reduces Cardiotoxicity While Increases Cardiotonic Effect of Aconitine in vitro

OBJECTIVE

To explore the synergic mechanism of ginsenoside Rg₁ (Rg₁) and aconitine (AC) by acting on normal neonatal rat cardiomyocytes (NRCMs) and pentobarbital sodium (PS)-induced damaged NRCMs.

METHODS

The toxic, non-toxic, and effective doses of AC and the most suitable compatibility concentration of Rg₁ for both normal and damaged NRCMs exposed for 1 h were filtered out by 3- (4,5)-dimethylthiahiazo (-z-y1)-3,5-diphenytetrazoliumromide, respectively. Then, normal NRCMs or impaired NRCMs were treated with chosen concentrations of AC alone or in combination with Rg₁ for 1 h, and the cellular activity, cellular ultrastructure, apoptosis, leakage of acid phosphatase (ACP) and lactate dehydrogenase (LDH), intracellular sodium ions [Na⁺], potassium ions [K⁺] and calcium ions [Ca²⁺] levels, and Nav1.5, Kv4.2, and RyR₂ genes expressions in each group were examined.

RESULTS

For normal NRCMs, 3000 µ mol/L AC significantly inhibited cell viability (P<0.01), promoted cell apoptosis, and damaged cell structures (P<0.05), while other doses of AC lower than 3000 µ mol/L and the combinations of AC and Rg₁ had little toxicity on NRCMs. Compared with AC acting on NRCMs alone, the co-treatment of 3000 and 10 µ mol/L AC with 1 µ mol/L Rg₁ significantly decreased the level of intracellular Ca²⁺ (P<0.01 or P<0.05), and the co-treatment of 3000 µ mol/L AC with 1 µ mol/L Rg₁ significantly decreased the level of intracellular Ca²⁺ via regulating Nav1.5, RyR₂ expression (P<0.01). For damaged NRCMs, 1500 µ mol/L AC aggravated cell damage (P<0.01), and 0.1 and 0.001 µ mol/L AC showed moderate protective effect. Compared with AC used alone, the co-treatment of Rg₁ with AC reduced the cell damage, 0.1 µ mol/L AC with 1 µ mol/L Rg₁ significantly inhibited the level of intracellular Na⁺ (P<0.05), 1500 µ mol/L AC with 1 µ mol/L Rg₁ significantly inhibited the level of intracellular K⁺ (P<0.01) via regulating Nav1.5, Kv4.2, RyR₂ expressions in impaired NRCMs.

CONCLUSION

Rg₁ inhibited the cardiotoxicity and enhanced the cardiotonic effect of AC via regulating the ion channels pathway of [Na⁺], [K⁺], and [Ca²⁺].

Transcriptomic Analysis Uncovers Immunogenic Characteristics of Ferroptosis for Myocardial Infarction and Potential Therapeutic Prediction of Chinese Herbs

Background

Inflammation and immune response play a key role in myocardial injury and repair after myocardial infarction (MI), while the relevant regulatory mechanisms of immune infiltration in MI have been fully explored. Ferroptosis is an iron-dependent form of regulated cell death characterized by an excessive accumulation of iron and lipid peroxides and involves in the pathogenesis of myocardial infarction. In the present study, by integrating intelligent data acquisition, data mining, network pharmacology, and computer-assisted target fishing, we developed a highly efficient system for screening immunity- and ferroptosis-related biomarkers and immunomodulatory ability of herbal ingredients.

Results

Immune infiltration analysis of GSE97320 showed significant neutrophil infiltration in the myocardial infarction group compared to the healthy group, and 807 differentially expressed genes (DEGs) were obtained (526 up-regulated and 281 downregulated). Among these DEGs, 73 immune-related and 8 ferroptosis-related DEGs were obtained. Further protein-protein interaction network analysis revealed 30 hub genes. The DEGs were enriched in a total of 107 biological processes, of which neutrophil-related biological processes were the most significant, enriched in 31 cellular components such as bead-binding hemoglobin complex, hemoglobin complex, and enriched in 36 functions such as bead-binding hemoglobin complex and hemoglobin complex. The DEGs were also enriched in 21 KEGG pathways such as lipid-atherosclerosis and formation of neutrophil extracellular traps. Further analysis identified Toll-like receptor-4 (TLR4) as the key gene, and based on TLR4, 17 herbal ingredients and 6 herbal medicines were predicted by using HERB and Coremine databases. Further molecular docking analysis showed that TLR4 could bind to salvianolic acid b and stigmasterol. The molecular dynamics analysis revealed that TLR4 could bind to salvianolic acid b, stigmasterol, and resveratrol in the stable phase with the binding between TLR4 and salvianolic acid b being the most stable.

Conclusions

TLR4 is a key gene that is related to ferroptosis and immune cell infiltration. Further analysis revealed that 17 herbal ingredients and 6 herbal medicines were predicted to have potential interactions with TLR4. These predicted herbal ingredients/medicines may act synergistically to protect against myocardial injury after MI through suppressing neutrophil extracellular traps. The protective effects may be associated with immune cell infiltration and ferroptosis.

Binding proteins PnCOX11 and PnDCD strongly respond to GA and ABA in Panax notoginseng

Panax notoginseng saponins (PNS) are one of the main active ingredients of Panax notoginseng, a representative plant of the genus Panax. However, the detailed regulation mechanism of PNS biosynthesis remains elusive. Therefore, a sequence of upstream promoters of PnSS and PnSE were cloned and analyzed firstly. GUS quantitative results showed that the upstream promoters could specifically and significantly respond to exogenous GA and ABA signals. To further identify the binding proteins that respond to peripheral hormones, PnCOX11 and PnDCD were screened and identified from the P. notoginseng cDNA library. The Y1H experiment verified the interaction between the above two binding proteins and the promoters. Several online software was used to analyze the domains, secondary structures, three-dimensional structures, and phylogenetic trees of the two binding proteins. Subcellular localization analysis exhibited that PnCOX11 was mainly located in the chloroplast, while PnDCD was located in the cytoplasm and nucleus. Prokaryotic expression demonstrated that the recombinant proteins had a high concentration under the induction of IPTG. This study can provide a fundamental date for the subsequent thorough investigation of the transcription regulatory mechanism of PNS biosynthesis.

Progress in the correlation of postoperative cognitive dysfunction and Alzheimer's disease and the potential therapeutic drug exploration

Postoperative cognitive dysfunction (POCD) is a decrease in mental capacity that can occur days to weeks after a medical procedure and may become permanent and rarely lasts for a longer period of time. With the continuous development of research, various viewpoints in academic circles have undergone subtle changes, and the role of anesthesia depth and anesthesia type seems to be gradually weakened; Alzheimer's disease (AD) is a latent and progressive neurodegenerative disease in the elderly. The protein hypothesis and the synaptic hypothesis are well-known reasons. These changes will also lead to the occurrence of an inflammatory cascade. The exact etiology and pathogenesis need to be studied. The reasonable biological mechanism affecting brain protein deposition, neuroinflammation, and acetylcholine-like effect has a certain relationship between AD and POCD. Whereas there is still further uncertainty about the mechanism and treatment, and it is elusive whether POCD is a link in the continuous progress of AD or a separate entity, which has doubts about the diagnosis and treatment of the disease. Therefore, this review is based on the current common clinical characteristics of AD and POCD, and pathophysiological research, to search for their common points and explore the direction and new strategies for future treatment.

Long Non-Coding RNAs in the Pathogenesis of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is one of the major microvascular complications of diabetes mellitus, with relatively high morbidity and mortality globally but still in short therapeutic options. Over the decades, a large body of data has demonstrated that oxidative stress, inflammatory responses, and hemodynamic disorders might exert critical influence in the initiation and development of DKD, whereas the delicate pathogenesis of DKD remains profoundly elusive. Recently, long non-coding RNAs (lncRNAs), extensively studied in the field of cancer, are attracting increasing attentions on the development of diabetes mellitus and its complications including DKD, diabetic retinopathy, and diabetic cardiomyopathy. In this review, we chiefly focused on abnormal expression and function of lncRNAs in major resident cells (mesangial cell, endothelial cell, podocyte, and tubular epithelial cell) in the kidney, summarized the critical roles of lncRNAs in the pathogenesis of DKD, and elaborated their potential therapeutic significance, in order to advance our knowledge in this field, which might help in future research and clinical treatment for the disease.

Non-Coding RNAs in Sepsis-Associated Acute Kidney Injury

Sepsis is a systemic inflammatory response caused by a severe infection that leads to multiple organ damage, including acute kidney injury (AKI). In intensive care units (ICU), the morbidity and mortality associated with sepsis-associated AKI (SA-AKI) are gradually increasing due to lack of effective and early detection, as well as proper treatment. Non-coding RNAs (ncRNAs) exert a regulatory function in gene transcription, RNA processing, post-transcriptional translation, and epigenetic regulation of gene expression. Evidence indicated that miRNAs are involved in inflammation and programmed cell death during the development of sepsis-associated AKI (SA-AKI). Moreover, lncRNAs and circRNAs appear to be an essential regulatory mechanism in SA-AKI. In this review, we summarized the molecular mechanism of ncRNAs in SA-AKI and discussed their potential in clinical diagnosis and treatment.

Krill oil prevents lipopolysaccharide-evoked acute liver injury in mice through inhibition of oxidative stress and inflammation

Acute liver injury is a life-threatening syndrome that often results from the actions of viruses, drugs and toxins. Herein, the protective effect and potential mechanism of krill oil (KO), a novel natural product rich in long-chain n-3 polyunsaturated fatty acids bound to phospholipids and astaxanthin, on lipopolysaccharide (LPS)-evoked acute liver injury in mice were investigated. Male C57BL/6J mice were administered intragastrically with 400 mg kg^-1 KO or fish oil (FO) once per day for 28 consecutive days prior to LPS exposure (10 mg kg^-1, intraperitoneally injected). The results revealed that KO pretreatment significantly ameliorated LPS-evoked hepatic dysfunction indicated by reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and attenuated hepatic histopathological damage. KO pretreatment also mitigated LPS-induced hepatic oxidative stress, as evidenced by decreased malondialdehyde (MDA) contents, elevated glutathione (GSH) levels, and elevated catalase (CAT) and superoxide dismutase (SOD) activities. Additionally, LPS-evoked overproduction of pro-inflammatory mediators in serum and the liver was inhibited by KO pretreatment. Furthermore, KO pretreatment suppressed LPS-induced activation of the hepatic toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/NOD-like receptor family pyrin domain containing 3 (NLRP3) signaling pathway. Interestingly, the hepatoprotective effect of KO was superior to that of FO. Collectively, the current findings suggest that KO protects against LPS-evoked acute liver injury via inhibition of oxidative stress and inflammation.

Alpha1-adrenoceptors activate NLRP3 inflammasome through downregulation of Kir2.1 in cardiac inflammation

NEW FINDINGS

What is the central question of this study? The mechanism of cardiac inflammation induced by α ₁ -AR stimulation by NLRP3 inflammasome activation is unclear. What is the main finding and its importance? In the mechanism of cardiac inflammation induced by α₁ -AR overreaction, Kir2.1 exerts cardioprotective and anti-inflammatory effects by inhibiting the activation of NLRP3 Inflammasome.

ABSTRACT

Overstimulated sympathetic nerves in cardiovascular diseases can lead to impaired cardiomyocyte function and potential heart failure, which activates not only β-AR but also α₁ -AR. A previous report indicated that NLRP3 inflammasome activation is involved in cardiac inflammation induced by the α₁ -AR agonist phenylephrine, but the mechanism is still unknown. Here, we aimed to study whether Kir2.1 is involved in cardiac inflammation caused by phenylephrine. The results from in vitro experiments showed that phenylephrine upregulated the expression levels of NLRP3, Caspase-1, IL-18, and IL-1β and downregulated the expression level of Kir2.1 in H9C2 cells. The Kir2.1 agonist zacopride downregulated the expression of NLRP3, Caspase-1, IL-1β and IL-18, and the Kir2.1 inhibitor ML133 upregulated the expression of these genes. To further explore the mechanism, we found that zacopride downregulated the protein expression level of p-p65 and that ML133 upregulated it. Moreover, the NF-κB signaling pathway inhibitor curcumenol reversed the expression of NLRP3 inflammasomes caused by phenylephrine in H9C2 cells. In vivo experiments, the protein expression level of Kir2.1 in the phenylephrine group was significantly decreased, and the activation of Kir2.1 by zacopride reduced cardiac inflammation. In short, Kir2.1 is related to α₁ -AR overactivation, which induces cardiac inflammation, through the NF-κB signaling pathway, and activating Kir2.1 can downregulate NLRP3 inflammation and exert cardioprotective effects by zacopride. This article is protected by copyright. All rights reserved.

Potential benefits of ginseng against COVID-19 by targeting inflammasomes

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogenic virus that causes coronavirus disease 2019 (COVID-19), with major symptoms including hyper-inflammation and cytokine storm, which consequently impairs the respiratory system and multiple organs, or even cause death. SARS-CoV-2 activates inflammasomes and inflammasome-mediated inflammatory signaling pathways, which are key determinants of hyperinflammation and cytokine storm in COVID-19 patients. Additionally, SARS-CoV-2 inhibits inflammasome activation to evade the host's antiviral immunity. Therefore, regulating inflammasome initiation has received increasing attention as a preventive measure in COVID-19 patients. Ginseng and its major active constituents, ginsenosides and saponins, improve the immune system and exert anti-inflammatory effects by targeting inflammasome stimulation. Therefore, this review discussed the potential preventive and therapeutic roles of ginseng in COVID-19 based on its regulatory role in inflammasome initiation and the host's antiviral immunity.

The Emerging Role of Ferroptosis in Sepsis

Ferroptosis is a novel form of cell death characterized by the iron-dependent accumulation of lipid peroxides and is different from other types of cell death. The mechanisms of ferroptosis are discussed in the review, including System Xc-, Glutathione Peroxidase 4 pathway, Ferroptosis Suppressor Protein 1 and Dihydroorotate Dehydrogenase pathway. Ferroptosis is associated with the occurrence of various diseases, including sepsis. Research in recent years has displayed that ferroptosis is involved in sepsis occurrence and development. Iron chelators can inhibit the development of sepsis and improve the survival rate of septic mice. The ferroptotic cells can release damage-associated molecular patterns and lipid peroxidation, which further mediate inflammatory responses. Ferroptosis inhibitors can resist sepsis-induced multiple organ dysfunction and inflammation. Finally, we reviewed ferroptosis, an iron-dependent form of cell death that is different from other types of cell death in biochemistry, morphology, and major regulatory mechanisms, which is involved in multiple organ injuries caused by sepsis. Exploring the relationship between sepsis and ferroptosis may yield new treatment targets for sepsis.

Transcription Factors Involved in the Development and Prognosis of Cardiac Remodeling

To compensate increasing workload, heart must work harder with structural changes, indicated by increasing size and changing shape, causing cardiac remodeling. However, pathological and unlimited compensated cardiac remodeling will ultimately lead to decompensation and heart failure. In the past decade, numerous studies have explored many signaling pathways involved in cardiac remodeling, but the complete mechanism of cardiac remodeling is still unrecognized, which hinders effective treatment and drug development. As gene transcriptional regulators, transcription factors control multiple cellular activities and play a critical role in cardiac remodeling. This review summarizes the regulation of fetal gene reprogramming, energy metabolism, apoptosis, autophagy in cardiomyocytes and myofibroblast activation of cardiac fibroblasts by transcription factors, with an emphasis on their potential roles in the development and prognosis of cardiac remodeling.

Ingredients with anti-inflammatory effect from medicine food homology plants

Inflammation occurs when the immune system responses to external harmful stimuli and infection. Chronic inflammation induces various diseases. A variety of foods are prescribed in the traditional medicines of many countries all over the world, which gave birth to the concept of medicine food homology. Over the past few decades, a number of secondary metabolites from medicine food homology plants have been demonstrated to have anti-inflammatory effects. In the present review, the effects and mechanisms of the medicine food homology plants-derived active components on relieving inflammation and inflammation-mediated diseases were summarized and discussed. The information provided in this review is valuable to future studies on anti-inflammatory ingredients derived from medicine food homology plants as drugs or food supplements.

Cardioprotective effects of bosentan in 5-fluorouracil-induced cardiotoxicity

5-fluorouracil (5-FU) is a widely used chemotherapeutic agent but cardiotoxicity challenges its clinical usefulness. Thus, searching for more cardioprotective drugs is highly required to prevent the accompanied cardiac hazards. Up to date, the different mechanisms involved in 5-FU cardiotoxicity are still unclear and there is no evaluation of bosentan's role in controlling these cardiac complications. This forced us to deeply study and evaluate the possible cardiopreserving properties of bosentan and different mechanisms involved in mediating it. 32 Wistar albino rats were included in our experiment and induction of cardiotoxicity was performed via administration of 5-FU (150 mg/kg) on 5th day of the experiment by intraperitoneal (i.p.) injection with or without co-administration of bosentan (50 mg/kg/day) orally for 7days. Our data revealed that 5-FU could induce cardiotoxicity which was detected as significant increases of troponin I, lactate dehydrogenase (LDH), creatine kinase- MB (CK-MB), endothelin receptors, malondialdehyde (MDA), toll like receptor4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor kappa B (NFκB), and caspase 3 levels. However, there is marked decrease in endothelial nitric oxide synthase (eNOS), reduced glutathione (GSH) and total antioxidant capacity (TAC). In addition, the histopathological examination showed severe toxic features of cardiac injury. Interestingly, co-administration of bosentan could ameliorate 5-FU-induced cardiotoxicity via improving the detected biochemical and histopathological changes besides modulation of TLR4/MyD88/NFκB signaling pathway, eNOS, and endothelin receptors. Bosentan had a significant cardioprotective effect against 5-FU induced cardiac damage. This effect may be attributed to its ability to inhibit endothelin receptors, stimulates eNOS, anti-oxidant, anti-inflammatory, anti-apoptotic properties with modulation of TLR4/MyD88/NFκB signaling pathway.

Yin Yang 1 (YY1)-induced long intergenic non-protein coding RNA 472 (LINC00472) aggravates sepsis-associated cardiac dysfunction via the micro-RNA-335-3p (miR-335-3p)/Monoamine oxidase A (MAOA) cascade

As a leading complication of sepsis, sepsis-induced cardiac dysfunction (SICD) contributed to the high mortality of patients with sepsis. Long non-coding RNA (LncRNA) LINC00472 has been reported to be in sepsis-induced disease. Nonetheless, its biological function and underlying molecular in SICD remain largely unknown. In this study, in vivo and in vitro SICD models were established via LPS treatment. H&E staining was employed for the evaluation of myocardial injury. ELISA assay was performed to detect cardiac Troponin I (cTnI), creatine kinase-MB (CK-MB), interleukin (IL)-1β, and tumor necrosis factor-α (TNF-α) levels. Cardiomyocyte viability and apoptosis were assessed via CCK-8 and flow cytometry assays. The transcriptional regulation of YY1 on LINC00472 was demonstrated via ChIP assay. Besides, the interaction between YY1 and LINC00472, as well as the association between miR-335-3p and LINC00472 or MAOA were verified via luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Herein, highly expressed LINC00472 was observed in both in vivo and in vitro SICD models. LINC00472 knockdown substantially attenuated LPS-induced inhibition on cardiomyocyte viability and reversed cardiomyocyte apoptosis and inflammatory response mediated by LPS treatment. YY1 induced LINC00472 upregulation, thereby promoting cardiomyocyte dysfunction induced by LPS. In addition, MAOA upregulation or miR-335-3p inhibition could partly reverse the suppressive effect on LPS-induced cardiomyocyte dysfunction mediated by LINC00472 knockdown. Based on our results, it seemed that YY1-activated LINC00472 might contribute to SICD progression via the miR-335-3p/MAOA pathway.

Ginsenoside Rd: A promising natural neuroprotective agent

BACKGROUND

Neurological diseases seriously affect human health, which are arousing wider attention, and it is a great challenge to discover neuroprotective drugs with minimal side-effects and better efficacies. Natural agents derived from herbs or plants have become unparalleled resources for the discovery of novel drug candidates. Panax ginseng C. A. Meyer, a well-known herbal medicine in China, occupies a very important position in traditional Chinese medicines (TCMs) with a long history of clinical application. Ginsenoside Rd is the active compound in P. ginseng known to have broad-spectrum pharmacological effects to reduce neurological damage that can lead to neurological diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, depression, cognitive impairment, and cerebral ischemia.

PURPOSE

To review and discuss the effects and mechanisms of ginsenoside Rd in the treatment of neurological diseases.

STUDY DESIGN & METHODS

The related information was compiled by the major scientific databases, such as Chinese National Knowledge Infrastructure (CNKI), Elsevier, ScienceDirect, PubMed, SpringerLink, Web of Science, and GeenMedical. Using 'Ginsenoside Rd', 'Ginsenosides', 'Anti-inflammation', 'Antioxidant', 'Apoptosis' and 'Neuroprotection' as keywords, the correlated literature was extracted and conducted from the databases mentioned above.

RESULTS

Through summarizing the existing research progress, we found that the general effects of ginsenoside Rd are anti-inflammatory, antioxidant, anti-apoptosis, inhibition of Ca²⁺ influx and protection of mitochondria, and through these pathways, the compound can inhibit excitatory toxicity, regulate nerve growth factor, and promote nerve regeneration.

CONCLUSION

Ginsenoside Rd is a promising natural neuroprotective agent. This review would contribute to the future development of ginsenoside Rd as a novel clinical candidate drug for treating neurological diseases.

Ginsenoside Rg1 Inhibits Microglia Pyroptosis Induced by Lipopolysaccharide Through Regulating STAT3 Signaling

Purpose

Neuroinflammation runs through the whole process of nervous system diseases and brain injury. Inflammasomes are thought to be especially relevant to immune homeostasis, and their dysregulation contributes to pyroptosis. The natural compound Ginsenoside Rg1 has been shown to possess anti-inflammatory effects; however, its underlying mechanisms are not entirely clear. Therefore, this study was undertaken to investigate the role and mechanisms of Rg1 in regulating the production of inflammasomes and pyroptosis of microglia in vivo and in vitro.

Methods

BV-2 microglial cells were pretreated with Rg1, stattic and interleukin-6 (IL-6), and then stimulated with lipopolysaccharide (LPS) (2μg/mL). Hoechst staining and Annexin V-FITC/PI assay were then carried out. The expression levels of cleaved-caspase-1, pro-caspase-1, interleukin-1β (IL-1β), mature-IL-1β, gasdermin D (GSDMD), activated NH(2)-terminal fragment of GSDMD (GSDMD-N), NOD-, LRR- and pyrin domain-containing 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), absent in melanoma 2 (AIM2), signal transducer and activator of transcription 3 (STAT3) and phosphorylated STAT3 in BV-2 were detected by Western blotting. Additionally, immunofluorescence staining was used to determine the expression of NLRP3 and p-STAT3 in postnatal rat brain and BV-2 microglia subjected to LPS stimulation and Rg1 pretreatment. The targets of transcription factor STAT3 were predicted by hTFtarget and chromatin immunoprecipitation (ChIP) was used to confirm the interaction between STAT3 and AIM2.

Results

We showed here that Rg1 effectively inhibited the expression of inflammasomes and microglia pyroptosis induced by LPS. The targets predicted data of Rg1 from Swiss target prediction database showed STAT3 had the highest thresholds of probability score. Rg1 can regulate the phosphorylation of STAT3, which binds to the promoter region of inflammasome AIM2.

Conclusion

It is suggested that STAT3 signaling can initiate the transcription activity of AIM2. Rg1 regulates microglia pyroptosis in neuroinflammation induced by LPS through targeting STAT3 signaling.

Immunoproteasome modulates NLRP3 inflammasome-mediated neuroinflammation under cerebral ischaemia and reperfusion conditions

Compelling evidence showed that both nucleotide‐binding oligomerization domain‐like receptor family, pyrin domain‐containing protein 3 (NLRP3) inflammasomes and the immunoproteasome participate in neuroinflammatory responses in cerebral ischaemia injury. Moreover, inhibition of either NLRP3 inflammasomes or the immunoproteasome attenuates both neuroinflammation and neurological deterioration during ischaemic stroke. However, the underlying mechanism between the immunoproteasome and NLRP3 inflammasomes under ischaemic stroke conditions remains to be established. In this study, using both in vitro and in vivo ischaemic models, we demonstrated that the immunoproteasome inhibition reduced the expressions of NLRP3 inflammasome‐associated proteins, including NLRP3, apoptosis‐associated speck‐like protein (ASC), caspase‐1 and mature cytokines (interleukin [IL]‐1β and IL‐18). It also downregulated the levels of nuclear factor (NF)‐κB and pyroptotic‐ and apoptotic‐related proteins, and improved cell viability. In addition, inhibition of NF‐κB by the small molecule inhibitor Bay‐11‐7082 led to lower levels of NLRP3 inflammasomes and cleaved caspase‐1 proteins in BV2 cells after oxygen‐glucose deprivation and reoxygenation. Together, these findings suggest that the immunoproteasome may be responsible for inducing the expression and activation of NLRP3 inflammasomes via the NF‐κB pathway. Therapeutic interventions that target activation of the immunoproteasome/NF‐κB/NLRP3 inflammasome pathway may provide novel prospects for the future treatment of ischaemic stroke.

Novel insights into antidepressant mechanism of Kai Xin San formula: Inhibiting NLRP3 inflammasome activation by promoting autophagy

BACKGROUND

Kai Xin San (KXS) was widely applied for the treatment of depression for thousands of years. However, the underlying antidepressant mechanism of KXS remains not clear.

PURPOSE

This study aimed to investigate whether NLRP3 inflammasome and autophagy are involved in inflammation-induced depression and antidepressant mechanism of KXS.

METHODS

Wistar rats were exposed to chronic unpredictable mild stress (CUMS) for 6 weeks, and KXS (3, 5, and 10 g/kg/d) was administrated during the last 2 weeks of CUMS procedure. The effects of KXS on depressive-like behaviors, neuroinflammation, NLRP3 inflammasome activation, and autophagy were investigated in CUMS rats. Rat astrocytes were employed to further explore the potential mechanism of KXS in regulating NLRP3 inflammasome and autophagy. Autophagy inhibitor 3-methyladenine (3-MA, 5 mM) was used in vitro to elucidate the role of autophagy in the antidepressant mechanism of KXS.

RESULTS

In vivo, KXS improved depressive-like behaviors of CUMS rats in sucrose preference test, open field test and forced swimming test. Moreover, KXS inhibited the neuroinflammation induced by CUMS and promoted autophagy in prefrontal cortex of rats. The results in vitro further validated the anti-inflammatory and proautohapgic effects of KXS. More importantly, autophagy inhibitor 3-MA diminished the inhibitory effect of KXS on NLRP3 inflammasome activation in rat astrocytes.

CONCLUSION

KXS ameliorated CUMS-induced depressive behaviors in rats and inhibited the NLRP3 inflammasome-mediated inflammation in vivo and in vitro. These effects might be regulated by KXS-induced autophagy.

Role of miR-145-5p/ CD40 in the inflammation and apoptosis of HUVECs induced by PM2.5

Fine particulate matter (PM_2.5) exposure can cause the injury of vascular endothelial cells by inflammatory response. CD40 works in inflammation of endothelial cells and it may be regulated by the miRNAs. This study aimed to clarify the role and mechanism of CD40 and miR-145-5p in PM_2.5-induced injury of human umbilical vein endothelial cells (HUVECs). HUVECs were treated with different concentrations of PM_2.5 exposure (0, 100, 200, 400 μg/mL) for 24 h. The si-RNA was used for CD40 gene silencing (0, 200 μg/mL PM_2.5, siRNA-CD40 and siRNA-CD40 + 200 μg/mL PM_2.5). Mimics was used for overexpression of miR-145-5p (0, 200 μg/mL PM_2.5, mimics and mimics+200 μg/mL PM_2.5). The cell viability of HUVECs was detected with Cell Counting Kit8 (CCK8) kit. The level of cell apoptosis was detected by flow cytometry. The inflammation-related factor including interleukin-1β (IL-1β), interleukin-18 (IL-18), tumor necrosis factor α (TNF-α) and C1q complement/tumor necrosis factor (TNF)-associated proteins9 (CTRP9) were tested with enzyme-linked immunosorbent assay (ELISA) kits. The mRNA and protein expression levels of CD40, CD40L, caspase1, NLRP3 (Nod-like receptor family pyrin domain-containing 3) and IKKB were detected with quantitative real-time PCR (qRT-PCR), Western blot and Immunofluorescence. Compared with the control group, the cell viability of HUVECs exposed to PM_2.5 was significantly decreased (p < 0.05); the levels of IL-Iβ and TNF-α were significantly increased, while the level of CTRP9 was significantly decreased (p < 0.05). The proportion of apoptotic cells was increased after being treated with PM_2.5 (p < 0.05). Besides, the mRNA and protein levels of CD40, CD40L, IKKB, NLRP3 and caspase1 were increased comparing with the control group (p < 0.05). After CD40 silencing, the condition of inflammation and apoptosis in HUVECs exposed to PM_2.5 was alleviated, and the expression levels of CD40L, IKKB, NLRP3 and caspase1 were significantly decreased (p < 0.05). Furthermore, miR-145-5p was significantly down-regulated after exposure to 200μg/mL PM_2.5 (p < 0.05). After over-expression of miR-145-5p, the expression level of CD40 was decreased (p < 0.05). Taken together, PM_2.5 can cause inflammation and apoptosis of HUVECs via the activation of CD40, which can be regulated by miR-145-5p. Over-expression of miR-145-5p can down-regulate CD40, further inhibiting the inflammation and apoptosis of HUVECs induced by PM_2.5.

Targeting the Nod-like receptor protein 3 Inflammasome with inhibitor MCC950 rescues lipopolysaccharide-induced inhibition of osteogenesis in Human periodontal ligament cells

OBJECTIVE

We aim to investigate whether lipopolysaccharide-stimulated activition of Nod-like receptor protein 3 (NLRP3) Inflammasome inhibits osteogenesis in Human periodontal ligament cells (HPDLCs). Futhermore, to study whether MCC950 (a inhibitor of NLRP3 Inflammasome) rescues lipopolysaccharide-induced inhibition of osteogenesis in HPDLCs as well as the underlying mechanisms.

METHODS

HPDLCs were isolated from periodontal ligament of healthy orthodontic teeth from teenagers, and cells surface marker protein were detected by flow cytometry. Cells viability were determined by Cell Counting kit 8 assay. Enzyme-linked immunosorbent assay was used to analyze the secretion of proinflammatory factors. Western blot and real-time quantitative polymerase chain reaction (RT-qPCR) were measured assessing the expression of NLRP3 and Caspase-1. RT-qPCR, Alizarin red staining and Alkaline phosphatase staining were tested to determine the osteogenic differentiation capacity of HPDLCs.

RESULTS

It was found that lipopolysaccharide in the range of concentrations from 10 to 100 μg/ml significantly inhibited HPDLCs viability at 24 h and significantly improved proinflammatory cytokine expressions at 8 h and 24 h. MCC950 reversed lipopolysaccharide-stimulated proinflammatory cytokine expressions including interleukin-1β and interleukin-18, but not tumor necrosis factor-α. In addition, MCC950 rescued the lipopolysaccharide-inhibited osteogenic gene (Alkaline phosphatase, Runt-related transcription factor 2, and Osteocalcin). Moreover, MCC950 downregulated lipopolysaccharide-induced relative protein of NLRP3 Inflammasome signaling pathway, such as NLRP3 and Caspase-1.

CONCLUSION

MCC950 rescues lipopolysaccharide-induced inhibition of osteogenesis in HPDLCs via blocking NLRP3 Inflammasome signaling pathway, and it may be used as a promising therapeutic agent for periodontitis or periondontal regenerative related disease.

An herbal preparation ameliorates heart failure with preserved ejection fraction by alleviating microvascular endothelial inflammation and activating NO-cGMP-PKG pathway

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous disease presenting a substantial challenge to clinicians. Currently, there is no safe and efficacious HFpEF treatment. In this study, we reported a standardized herbal medicinal product, QiShenYiQi (QSYQ), that can be used in the treatment of HFpEF.

METHODS

HFpEF mice were established by infusing a combination of N^ω-nitro-L-arginine methyl ester (L-NAME) and feeding them a high-fat diet for 14 weeks. In the 10th week, the HFpEF mice were given dapagliflozin or QSYQ via oral gavage for four weeks. The blood pressure, echocardiography, hemodynamics, leukocyte infiltration, and oxidative stress in HFpEF mice were evaluated. Besides, inflammatory factors, endothelial adhesion factors, and endothelial-mesenchymal transformation (EndMT) markers were investigated.

RESULTS

QSYQ significantly attenuated concentric cardiac remodeling while improving diastolic function and left ventricular compliance in HFpEF mice. QSYQ also inhibited inflammation and immunocyte recruitment during HFpEF. The infiltration of CD8⁺, CD4⁺ T cells, and CD11b/c⁺ monocytes was substantially mitigated in the myocardium of QSYQ-treated mice. TNF-α, MCP-1, NF-κB, and NLRP3 levels also reduced after QSYQ treatment. Furthermore, QSYQ significantly reversed the elevated expression of endothelial adhesion factors and EndMT occurrence. These effects of QSYQ were demonstrated by the activation of NO-cGMP-PKG pathway and reduction of eNOS uncoupling in the HFpEF heart.

CONCLUSION

These results provide novel evidence that QSYQ treatment improves HFpEF by inhibiting microvascular endothelial inflammation and activating NO-cGMP-PKG pathway.

Dehydrocorydaline Protects Against Sepsis-Induced Myocardial Injury Through Modulating the TRAF6/NF-κB Pathway

We aim to investigate the effect and mechanism of dehydrocorydaline (Deh), an alkaloidal component isolated from Rhizoma corydalis, in the treatment of sepsis-mediated myocardial injury. Lipopolysaccharide (LPS) was taken to construct an in-vitro sepsis-myocardial injury models H9C2 cardiomyocytes. The in-vivo model of sepsis in C57BL/6 mice was induced by intraperitoneal injection of Escherichia coli (E. coli). The in-vitro and in-vivo models were treated with Deh in different concentrations, respectively. Hematoxylin-eosin (HE) staining, Masson staining, and immunohistochemistry (IHC) staining were taken to evaluate the histopathological changes of the heart. ELISA was applied to evaluate the levels of inflammatory factors, including IL-6, IL-1β, TNFα, IFNγ, and oxidized factors SOD, GSH-PX in the plasma or culture medium. Western blot was used to measure the expressions of Bax, Bcl2, Caspase3, iNOS, Nrf2, HO-1, TRAF6, NF-κB in heart tissues and cells. The viability of H9C2 cardiomyocytes was detected by the CCK8 method and BrdU assay. The ROS level in the H9C2 cardiomyocytes were determined using immunofluorescence. As a result, Deh treatment improved the survival of sepsis mice, reduced TUNEL-labeled apoptosis of cardiomyocytes. In vitro, Deh enhanced the viability of LPS-induced H9C2 cardiomyocytes and inhibited cell apoptosis. Additionally, Deh showed significant anti-inflammatory and anti-oxidative stress functions via decreasing IL-1β, IL-6, TNFα, and IFNγ levels, mitigating ROS level, up-regulating Nrf2/HO-1, SOD, and GSH-PX expressions dose-dependently. Mechanistically, Deh inhibited TRAF6 expression and the phosphorylation of NF-κB p65. The intervention with a specific inhibitor of TRAF6 (C25-140) or NF-κB inhibitor (BAY 11-7082) markedly repressed the protective effects mediated by Deh. In conclusion, Deh restrains sepsis-induced cardiomyocyte injury by inhibiting the TRAF6/NF-κB pathway.

Ginsenoside Rg1 exerts neuroprotective effects in 3-nitropronpionic acid-induced mouse model of Huntington's disease via suppressing MAPKs and NF-κB pathways in the striatum

Huntington's disease (HD) is one of main neurodegenerative diseases, characterized by striatal atrophy, involuntary movements, and motor incoordination. Ginsenoside Rg1 (Rg1), an active ingredient in ginseng, possesses a variety of neuroprotective effects with low toxicity and side effects. In this study, we investigated the potential therapeutic effects of Rg1 in a mouse model of HD and explored the underlying mechanisms. HD was induced in mice by injection of 3-nitropropionic acid (3-NP, i.p.) for 4 days. From the first day of 3-NP injection, the mice were administered Rg1 (10, 20, 40 mg·kg^-1, p.o.) for 5 days. We showed that oral pretreatment with Rg1 alleviated 3-NP-induced body weight loss and behavioral defects. Furthermore, pretreatment with Rg1 ameliorated 3-NP-induced neuronal loss and ultrastructural morphological damage in the striatum. Moreover, pretreatment with Rg1 reduced 3-NP-induced apoptosis and inhibited the activation of microglia, inflammatory mediators in the striatum. We revealed that Rg1 exerted neuroprotective effects by suppressing 3-NP-induced activation of the MAPKs and NF-κΒ signaling pathways in the striatum. Thus, our results suggest that Rg1 exerts therapeutic effects on 3-NP-induced HD mouse model via suppressing MAPKs and NF-κΒ signaling pathways. Rg1 may be served as a novel therapeutic option for HD.

Danshensu attenuates cisplatin-induced nephrotoxicity through activation of Nrf2 pathway and inhibition of NF-κB

The clinical application of cisplatin was mainly limited by severe nephrotoxicity. Danshensu was the main pharmacological active diterpenoids which extracted from the roots of Salvia milthiorriza Bunge. This study is aimed to investigate the protective effects and potential mechanisms of Danshensu against cisplatin-induced nephrotoxicity. After fasting for 12 h, all mice groups except the control group were administered a single intraperitoneal injection of 25 mg/kg cisplatin. 1 h later, cisplatin (25 mg/kg) + Danshensu (15 mg/kg, 30 mg/kg, 60 mg/kg) groups were treated with corresponding doses of Danshensu once a day for 7 consecutive days. Blood urea nitrogen (BUN), creatinine, reactive oxygen species (ROS), superoxide dismutase (SOD), Glutathione peroxidase (GPx), Catalase (CAT) and malondialdehyde (MDA) were assayed in this study. The expression of inflammatory cytokines TNF-α, IL-6 and IL-1β were examined by ELISA. The results showed that Danshensu could improve kidney damage, attenuate serum BUN, creatinine, cytokines and oxidative stress markers. Further studies showed that Danshensu can induce Nrf2/HO-1 activation and inhibition of NF-κB pathway. In conclusion, Danshensu exerts the protective effects on cisplatin-induced nephrotoxicity, which may be related to the activation of Nrf2/HO-1 and inhibition of NF-ĸB pathway.

Ginsenoside Rg1 enhances the healing of injured tendon in achilles tendinitis through the activation of IGF1R signaling mediated by oestrogen receptor

Background

During the pathogenesis of tendinopathy, the chronic inflammation caused by the injury and apoptosis leads to the generation of scars. Ginsenoside Rg1 (Rg1) is extracted from ginseng and has anti-inflammatory effects. Rg1 is a unique phytoestrogen that can activate the estrogen response element. This research aimed to explore whether Rg1 can function in the process of tendon repair through the estrogen receptor.

Methods

In this research, the effects of Rg1 were evaluated in tenocytes and in a rat model of Achilles tendinitis (AT). Protein levels were shown by western blotting. qRT-PCR was employed for evaluating mRNA levels. Cell proliferation was evaluated through EdU assay and cell migration was evaluated by transwell assay and scratch test assay.

Results

Rg1 up-regulated the expression of matrix-related factors and function of tendon in AT rat model. Rg1 reduced early inflammatory response and apoptosis in the tendon tissue of AT rat model. Rg1 promoted tenocyte migration and proliferation. The effects of Rg1 on tenocytes were inhibited by ICI182780. Rg1 activates the insulin-like growth factor-I receptor (IGF1R) and MAPK signaling pathway.

Conclusion

Rg1 promotes injured tendon healing in AT rat model through IGF1R and MAPK signaling pathway activation.

Methylglyoxal-Derived Advanced Glycation End Product (AGE4)-Induced Apoptosis Leads to Mitochondrial Dysfunction and Endoplasmic Reticulum Stress through the RAGE/JNK Pathway in Kidney Cells

Advanced glycation end products (AGEs) are formed via nonenzymatic reactions between reducing sugars and proteins. Recent studies have shown that methylglyoxal, a potent precursor for AGEs, causes a variety of biological dysfunctions, including diabetes, inflammation, renal failure, and cancer. However, little is known about the function of methylglyoxal-derived AGEs (AGE4) in kidney cells. Therefore, we verified the expression of endoplasmic reticulum (ER) stress-related genes and apoptosis markers to determine the effects of AGE4 on human proximal epithelial cells (HK-2). Moreover, our results showed that AGE4 induced the expression of apoptosis markers, such as Bax, p53, and kidney injury molecule-1, but downregulated Bcl-2 and cyclin D1 levels. AGE4 also promoted the expression of NF-κB, serving as a transcription factor, and the phosphorylation of c-Jun NH₂-terminal kinase (JNK), which induced cell apoptosis and ER stress mediated by the JNK inhibitor. Furthermore, AGE4 induced mitochondrial dysfunction by inducing the permeabilization of the mitochondrial membrane and ATP synthesis. Through in vitro and in vivo experiments, this study provides a new perspective on renal dysfunction with regard to the AGE4-induced RAGE /JNK signaling pathway, which leads to renal cell apoptosis via the imbalance of mitochondrial function and ER stress in kidney damage.

Ginsenoside Rg1 can restore hematopoietic function by inhibiting Bax translocation-mediated mitochondrial apoptosis in aplastic anemia

The present study investigated, the anti-apoptotic activity of Ginsenoside Rg1 (Rg1) via inhibition of Bax translocation and the subsequent recovery of hematopoietic function. Mitochondrial apoptosis in bone marrow mononuclear cells (BMNCs) was observed in aplastic anemia (AA) patients. To establish a mouse model of AA, BALB/c mice were transplanted with lymph node cells from DBA/2 donor mice via vein injection after treatment with Co60 γ-radiation. After treatment with Rg1 for 14 days, the peripheral blood and Lin–Sca-1 + c-Kit + (LSK) cell counts of the treated group were increased compared with those of the untreated model mice. In in vivo and in vitro tests of LSKs, Rg1 was found to increase mitochondrial number and the ratio of Bcl-2/Bax and to decrease damage to the mitochondrial inner and outer membranes, the mitochondrial Bax level and the protein levels of mitochondrial apoptosis-related proteins AIF and Cyt-C by decreasing the ROS level. Rg1 also improved the concentration–time curve of MAO and COX and levels of ATP, ADP and AMP in an in vitro test. In addition, high levels of Bax mitochondrial translocation could be corrected by Rg1 treatment. Levels of markers of mitochondrial apoptosis in the Rg1-treated group were significantly better than those in the AA model group, implying that Rg1 might improve hematopoietic stem cells and thereby restore hematopoietic function in AA by suppressing the mitochondrial apoptosis mediated by Bax translocation.

Morin alleviates hepatic ischemia/reperfusion-induced mischief: In vivo and in silico contribution of Nrf2, TLR4, and NLRP3

OBJECTIVE

Morin (MRN), a known natural flavonol, has demonstrated its shielding aptitude against ischemia/reperfusion (I/Re) lesion in various organs. Nonetheless, its potential influence on hepatic I/Re-induced injury modulation has not been fully elucidated. Consequently, the current study strived to investigate the mechanistic maneuvering of MRN against hepatic I/Re. Furthermore, the effects of MRN on Nrf2, TLR4, and NLRP3 proteins were evaluated via molecular docking studies.

METHODS

For fulfilling this aim, Sprague-Dawley rats were allotted into 4 groups; Sham-operated (ShG), hepatic I/Re (30 min/24 h), and 10 days orally pre-treated MRN (50 and 100 mg/kg).

KEY FINDINGS

MRN mechanistic maneuver disclosed its ability to safeguard the hepatocytes partially due to antioxidant aptitude through intensifying the expression/content of Nrf2/HO-1 trajectory accompanied by total antioxidant capacity boosting besides MDA lessening. In addition, MRN anti-inflammatory attribute was affirmed by downsizing the expression/content of TLR4/NF-κB trajectory accompanied by a sequent lessening of TNF-α, IL-1β, IL-6, and ICAM-1 content. Moreover, MRN action entangled NLRP3 inhibitory character with subsequent MPO rebating. Furthermore, MRN anti-apoptotic trait verified by diminishing the pro-apoptotic and the executioner markers; Bax and caspase-3 levels, respectively. On the other hand, MRN administration proved its shielding action by improving the histopathological deterioration and lessening the serum ALT and AST levels. Finally, in silico studies exhibited moderate to promising binding affinities of MRN with the selected proteins ranging from -4.23 to -6.09 kcal mol-1.

CONCLUSION

Higher and lower doses of MRN purveyed plausible defensive mechanisms and abated episodes concomitant with hepatic I/Re mischief in part, by modifying oxidative status and inflammation by the impact on Nrf2/HO-1, TLR4/ NF-κB, and NLRP3 pathway.

The protective role of fosfomycin in lung injury due to oxidative stress and inflammation caused by sepsis

AIM

Early and prompt treatment of sepsis by effective antibiotics against susceptible organisms may be lifesaving. However, increased antibiotic resistance and side effects of chemotherapeutic agents limiting their tolerability result in a restricted use of medications. This has led to an increased search for solution oriented novel treatments and therapeutic targets, as well as investigations on the pathogenesis and physiology of sepsis. In this study, we aimed to examine the antioxidant and anti-inflammatory effects of fosfomycin in sepsis resulting from other causes.

MAIN METHODS

Sprague Dawley rats were assigned into three groups. Randomly selected control rats received intraperitoneal saline solution only. Only caecal puncture and ligation were carried out in the caecal ligation and puncture (CLP) group, while in the CLP + fosfomycin group (CLP + FOS), together with sepsis due to caecal puncture and ligation, 500 mg/kg of FOS was administered intraperitoneally (i.p.).

KEY FINDINGS

As compared to the control group, elevated TBARS and TNF-α levels as well as increased expression of NF-kB/p65 and TLR-4 and reduced -SH levels were found in the lung tissue of CLP rats. On the other hand, TBARS and TNF-α levels were reduced and NF-kB/p65 and TLR-4 expressions were decreased together with increase in total -SH levels among CLP + FOS (500 mg/kg i.p.) rats.

SIGNIFICANCE

FOS treatment may represent a promising agent in terms of reducing the sepsis-related lung injury due to its antimicrobial effects as well as its antioxidant and anti-inflammatory properties.

Ginsenoside Rg1 alleviates lipopolysaccharide-induced neuronal damage by inhibiting NLRP1 inflammasomes in HT22 cells

Lipopolysaccharide (LPS) is a toxic component of cell walls of Gram-negative bacteria that are widely present in gastrointestinal tracts. Increasing evidence showed that LPS plays important roles in the pathogeneses of neurodegenerative disorders, such as Alzheimer's disease (AD). NADPH oxidase s2 (NOX2) is a complex membrane protein that contributes to the production of reactive oxygen species (ROS) in several neurological diseases. The NLRP1 inflammasome can be activated in response to an accumulation of ROS in neurons. However, it is still unknown whether LPS exposure can deteriorate neuronal damage by activating NOX2-NLRP1 inflammasomes. Ginsenoside Rg1 (Rg1) has protective effects on neurons, although whether Rg1 alleviates LPS-induced neuronal damage by inhibiting NOX2-NLRP1 inflammasomes remains unclear. In the present study, the effect of concentration gradients and different times of LPS exposure on neuronal damage was investigated in HT22 cells, and further observed the effect of Rg1 treatment on NOX2-NLPR1 inflammasome activation, ROS production and neuronal damage in LPS-treated HT22 cells. The results demonstrated that LPS exposure significantly induced NOX2-NLRP1 inflammasome activation, excessive production of ROS, and neuronal damage in HT22 cells. It was also shown that Rg1 treatment significantly decreased NOX2-NLRP1 inflammasome activation and ROS production and alleviated neuronal damage in LPS-induced HT22 cells. The present data suggested that Rg1 has protective effects on LPS-induced neuronal damage by inhibiting NOX2-NLRP1 inflammasomes in HT22 cells, and Rg1 may be a potential therapeutic approach for delaying neuronal damage in AD.

Adiponectin Attenuates Lipopolysaccharide-induced Apoptosis by Regulating the Cx43/PI3K/AKT Pathway

Cardiomyocyte apoptosis is a crucial factor leading to myocardial dysfunction. Adiponectin (APN) has a cardiomyocyte-protective impact. Studies have shown that the connexin43 (Cx43) and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathways play an important role in the heart, but whether APN plays a protective role by regulating these pathways is unclear. Our study aimed to confirm whether APN protects against lipopolysaccharide (LPS)-induced cardiomyocyte apoptosis and to explore whether it plays an important role through regulating the Cx43 and PI3K/AKT signaling pathways. In addition, our research aimed to explore the relationship between the Cx43 and PI3K/AKT signaling pathways. In vitro experiments: Before H9c2 cells were treated with LPS for 24 h, they were pre-treated with APN for 2 h. The cytotoxic effect of APN on H9c2 cells was evaluated by a CCK-8 assay. The protein levels of Bax, Bcl2, cleaved caspase-3, cleaved caspase-9, Cx43, PI3K, p-PI3K, AKT and p-AKT were evaluated by Western blot analysis, and the apoptosis rate was evaluated by flow cytometry. APN attenuated the cytotoxicity induced by LPS. LPS upregulated Bax, cleaved caspase-3 and cleaved caspase-9 and downregulated Bcl2 in H9c2 cells; however, these effects were attenuated by APN. In addition, LPS upregulated Cx43 expression, and APN downregulated Cx43 expression and activated the PI3K/AKT signaling pathway. LPS induced apoptosis and inhibited PI3K/AKT signaling pathway in H9c2 cells, and these effects were attenuated by Gap26 (a Cx43 inhibitor). Moreover, the preservation of APN expression was reversed by LY294002 (a PI3K/AKT signaling pathway inhibitor). In vivo experiments: In C57BL/6J mice, a sepsis model was established by intraperitoneal injection of LPS, and APN was injected into enterocoelia. The protein levels of Bax, Bcl2, cleaved caspase-3, and Cx43 were evaluated by Western blot analysis, and immunohistochemistry was used to detect Cx43 expression and localization in myocardial tissue. LPS upregulated Bax and cleaved caspase-3 and downregulated Bcl2 in sepsis; however, these effects were attenuated by APN. In addition, the expression of Cx43 was upregulated in septic myocardial tissue, and APN downregulated Cx43 expression in septic myocardial tissue. In conclusion, both in vitro and in vivo, the data demonstrated that APN can protect against LPS-induced apoptosis during sepsis by modifying the Cx43 and PI3K/AKT signaling pathways.

CLEC5A knockdown protects against the cardiac dysfunction after Myocardial infarction by suppressing macrophage polarization, NLRP3 inflammasome activation and pyroptosis

Increasing evidence has shown that NOD-like receptor protein 3 (NLRP3) inflammasome and pyroptotic cell death play vital roles in the pathophysiology of myocardial infarction (MI), a common cardiovascular disease characterized with cardiac dysfunction. C-type lectin member 5A (CLEC5A) is reported to strongly associate with activation of NLRP3 inflammasome and pyroptosis. In this study, in vivo MI model was established by the ligation of left anterior descending coronary artery on male C57BL/6 mice, and CLEC5A knockdown was further achieved by intra-myocardial injection of adenovirus delivering shRNA-CLEC5A. CLEC5A was found to be highly expressed in left ventricular of MI mice, while CLEC5A knockdown conversely alleviated the cardiac dysfunction in MI mice. Besides, MI-induced classical activation of macrophages was significantly inhibited after CLEC5A silencing. Additionally, CLEC5A knockdown dramatically inhibited MI-triggered activation of NLRP3 inflammasome, pyroptosis and NF-κB signaling in left ventricular of mice. In vitro experiment further validated that CLEC5A knockdown suppressed M1 polarization in LPS/IFNγ-stimulated RAW264.7 cells, and inhibited the polarized RAW264.7-induced activation of NLRP3 inflammasome/pyroptosis signaling in co-cultured cardiomyocytes. In conclusion, CLEC5A knockdown protects against the MI-induced cardiac dysfunction by regulating macrophage polarization, NLRP3 inflammasome and cell pyroptosis.

Pinocembrin alleviates lipopolysaccharide-induced myocardial injury and cardiac dysfunction in rats by inhibiting p38/JNK MAPK pathway

AIM

Recent studies have shown that, with its excellent anti-inflammatory and antioxidant effects, pinocembrin can reduce the occurrence of arrhythmia in myocardial infarction rats. However, whether it can alleviate lipopolysaccharide (LPS)-induced myocardial injury in rats has not been reported. Therefore, the purpose of this study was to investigate whether pinocembrin could alleviate myocardial injury and arrhythmia in rats with sepsis.

MATERIALS AND METHODS

Rats were intraperitoneally injected with LPS to simulate animal sepsis, and the caudal vein was injected with pinocembrin or normal saline for intervention. Transthoracic echocardiography, inflammatory factors, electrophysiological recording, histological analysis, and western-blot analysis were performed.

KEY FINDINGS

Compared with the control group, the rats in the LPS group had myocardial injury and cardiac dysfunction, and the incidence of ventricular arrhythmia increased. In addition, LPS resulted in the increase of p-c-Jun N-terminal kinase (JNK), p-p38 proteins in the myocardium, the levels of inflammatory factors in the blood and the apoptosis rate of left ventricular cardiomyocytes. And all these adverse effects were eliminated, thus confirming that pinocembrin has an excellent protective effect on the heart.

SIGNIFICANCE

Reducing the inflammatory response and cell apoptosis by inhibiting p38/JNK mitogen-activated protein kinase (MAPK) signaling pathway, pinocembrin can alleviate myocardial injury, cardiac dysfunction, and ventricular arrhythmia induced by LPS.