Interleukin-35 pretreatment attenuates lipopolysaccharide-induced heart injury by inhibition of inflammation, apoptosis and fibrotic reactions

Yohimbine Treatment Alleviates Cardiac Inflammation/Injury and Improves Cardiac Hemodynamics by Modulating Pro-Inflammatory and Oxidative Stress Indicators

Acute myocarditis, also known as myocardial inflammation, is a self-limited condition caused by systemic infection with cardiotropic pathogens, primarily viruses, bacteria, or fungi. Despite significant research, inflammatory cardiomyopathy exacerbated by heart failure, arrhythmia, or left ventricular dysfunction and it has a dismal prognosis. In this study, we aimed to evaluate the therapeutic effect of yohimbine against lipopolysaccharide (LPS) induced myocarditis in rat model. The anti-inflammatory activity of yohimbine was assessed in in-vitro using RAW 264.7 and H9C2 cells. Myocarditis was induced in rats by injecting LPS (10 mg/kg), following the rats were treated with dexamethasone (2 mg/kg) or yohimbine (2.5, 5, and 10 mg/kg) for 12 h and their therapeutic activity was examined using various techniques. Yohimbine treatment significantly attenuated the LPS-mediated inflammatory markers expression in the in-vitro model. In-vivo studies proved that yohimbine treatment significantly reduced the LPS-induced increase of cardiac-specific markers, inflammatory cell counts, and pro-inflammatory markers expression compared to LPS-control samples. LPS administration considerably affected the ECG, RR, PR, QRS, QT, ST intervals, and hemodynamic parameters, and caused abnormal pathological parameters, in contrast, yohimbine treatment substantially improved the cardiac parameters, mitigated the apoptosis in myocardial cells and ameliorated the histopathological abnormalities that resulted in an improved survival rate. LPS-induced elevation of cardiac troponin-I, myeloperoxidase, CD-68, and neutrophil elastase levels were significantly attenuated upon yohimbine treatment. Further investigation showed that yohimbine exerts an anti-inflammatory effect partly by modulating the MAPK pathway. This study emphasizes yohimbine's therapeutic benefit against LPS-induced myocarditis and associated inflammatory markers response by regulating the MAPK pathway.

IL-35 ameliorates lipopolysaccharide-induced endothelial dysfunction by inhibiting endothelial-to-mesenchymal transition

Sepsis is a systemic inflammatory response syndrome (SIRS) caused mainly by bacterial infection. The morbidity and mortality rates of sepsis are extremely high. About 18 million people worldwide suffer from severe sepsis each year, and about 14,000 people die from it every day. Previous studies have revealed that endothelial dysfunction plays a vital role in the pathological change of sepsis. Furthermore, endothelial-mesenchymal transition (EndMT, EndoMT) is capable of triggering endothelial dysfunction. And yet, it remains obscure whether interleukin-35 (IL-35) can alleviate endothelial dysfunction by attenuating LPS-induced EndMT. Here, through in vivo and in vitro experiments, we revealed that IL-35 has a previously unknown function to attenuate LPS-induced endothelial dysfunction by inhibiting LPS-induced EndMT. Mechanistically, IL-35 acts by regulating the NFκB signaling pathway.

Current insight on the mechanisms of programmed cell death in sepsis-induced myocardial dysfunction

Sepsis is a clinical syndrome characterized by a dysregulated host response to infection, leading to life-threatening organ dysfunction. It is a high-fatality condition associated with a complex interplay of immune and inflammatory responses that can cause severe harm to vital organs. Sepsis-induced myocardial injury (SIMI), as a severe complication of sepsis, significantly affects the prognosis of septic patients and shortens their survival time. For the sake of better administrating hospitalized patients with sepsis, it is necessary to understand the specific mechanisms of SIMI. To date, multiple studies have shown that programmed cell death (PCD) may play an essential role in myocardial injury in sepsis, offering new strategies and insights for the therapeutic aspects of SIMI. This review aims to elucidate the role of cardiomyocyte's programmed death in the pathophysiological mechanisms of SIMI, with a particular focus on the classical pathways, key molecules, and signaling transduction of PCD. It will explore the role of the cross-interaction between different patterns of PCD in SIMI, providing a new theoretical basis for multi-target treatments for SIMI.

NLRP3 inflammasome involves in the pathophysiology of sepsis-induced myocardial dysfunction by multiple mechanisms

Sepsis-induced myocardial dysfunction (SIMD) is one of the serious health-affecting problems worldwide. At present, the mechanisms of SIMD are still not clearly elucidated. The NOD-like receptor protein 3 (NLRP3) inflammasome has been assumed to be involved in the pathophysiology of SIMD by regulating multiple biological processes. NLRP3 inflammasome and its related signaling pathways might affect the regulation of inflammation, autophagy, apoptosis, and pyroptosis in SIMD. A few molecular specific inhibitors of NLRP3 inflammasome (e.g., Melatonin, Ulinastatin, Irisin, Nifuroxazide, and Ginsenoside Rg1, etc.) have been developed, which showed a promising anti-inflammatory effect in a cellular or animal model of SIMD. These experimental findings indicated that NLRP3 inflammasome could be a promising therapeutic target for SIMD treatment. However, the clinical translation of NLRP3 inhibitors for treating SIMD still requires robust in vivo and preclinical trials.

Impaired Regulation by IL-35 in Systemic Sclerosis

This study investigated the role of IL-35 in systemic sclerosis (SSc) patients, focusing on CD4+ T cell response and immunomodulatory cytokine production. By comparing the cytokine levels in healthy donors (HD) and SSc patients using ELISAs, we found a significantly lower plasma IL-35 concentration in the SSc patients (52.1 ± 5.6 vs. 143 ± 11.1, p < 0.001). Notably, the IL-35 levels showed a negative correlation with TGF-β (p < 0.001) and IL-17 (p = 0.04). Assessing the IL-35R expression across cell types in the SSc patients and HDs via flow cytometry, we found higher levels on monocytes (40.7 + 5.7 vs. 20.3 ± 1.9, p < 0.001) and lower levels on CD8+ T cells (61.8 ± 9.2 vs. 83.4 ± 0.8, p < 0.05) in the SSc patients. The addition of recombinant IL-35 to stimulated peripheral blood mononuclear cells reduced the IL-17+CD4+ T cell percentage (9.0 ± 1.5 vs. 4.8 ± 0.7, p < 0.05) and increased the IL-35+CD4+ T percentage (4.1 ± 2.3 vs. 10.2 ± 0.8, p < 0.001). In a Treg:Tresponder cell Sco-culture assay with HD and SSc samples, rIL35 decreased the cell proliferation and levels of IL-17A (178.2 ± 30.5 pg/mL vs. 37.4 ± 6.4 pg/mL, p < 0.001) and TGF-β (4194 ± 777 pg/mL vs. 2413 ± 608 pg/mL, p < 0.01). Furthermore, we observed a positive correlation between the modified Rodnan skin score (mRSS) and TGF-β (p < 0.001), while there was a negative correlation between mRSS and IL-35 (p = 0.004). Interestingly, higher levels of plasmatic IL-35 were detected in individuals with limited disease compared to those with diffuse disease (60.1 ± 8.0 vs. 832.3 ± 4.1, p < 0.05). These findings suggest that IL-35 exhibits anti-inflammatory properties in SSc and it may serve as a marker for disease severity and a therapeutic target.

The protective effects of sophocarpine on sepsis-induced cardiomyopathy

This investigation elucidates the impact of sophocarpine treatment on lipopolysaccharide (LPS) stimulated sepsis-induced cardiomyopathy (SIC) via in vivo and in vitro experiments. Echocardiography, ELISA, TUNEL, Western blotting experiments, and Hematoxylin/Eosin, Dihydroethidium, and Immunohistochemistry staining assays, were carried out to identify associated indicators. The echocardiography revealed that sophocarpine treatment alleviated LPS-induced cardiac dysfunction as indicated by fractional shortening shortened and improved ejection fraction. Heart injury biomarkers, such as creatine kinase, lactate dehydrogenase, and creatine kinase-MB, were assessed, and indicated that sophocarpine treatment could alleviate LPS-induced upregulation of these indices. Furthermore, different experimental protocols revealed that sophocarpine treatment inhibits LPS-induced pathological alterations and decreases LPS-stimulated inflammatory cytokines, IL-1β, monocyte chemoattractant protein-1, IL-6, NOD-like receptor protein-3, and TNF-α, increase. Apoptotic proteins such as cytochrome-c, Bax, and cleaved-caspase-3 were increased, and Bcl-2 was alleviated after LPS stimulation; however, these effects were inhibited by sophocarpine treatment. Decreased antioxidant proteins [superoxide dismutase-1 (SOD-1) and SOD-2] induced by LPS stimulation were upregulated by sophocarpine treatment. LPS upregulated autophagic proteins such as Beclin-1 and the ratio of microtubule-associated protein 1A/1B-light chain 3 (LC3)-II/LC3-I and downregulated sequestosome 1 (SQSTM1, or P62), sophocarpine therapy reversed these effects. Moreover, it was indicated that sophocarpine treatment inhibited the Toll-like receptor-4 (TLR-4)/nuclear transcription factor-kappa B (NF-κB) signaling pathway and activated nuclear factor erythroid 2-related factor-2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. In conclusion, sophocarpine treatment could alleviate LPS-trigger SIC by repressing oxidative stress, autophagy, inflammation, and apoptosis via TLR-4/NF-κB inhibition and Nrf2/HO-1 signaling pathway activation, implicating the potential of sophocarpine as a new therapeutic approach against SIC.

Myo-inositol oxygenase (MIOX) accelerated inflammation in the model of infection-induced cardiac dysfunction by NLRP3 inflammasome

BACKGROUND

Cardiac dysfunction is an important component of multiple organ failure caused by sepsis, and an important cause of high mortality in patients with sepsis. Herein, we attempted to determine whether myo-inositol oxygenase (MIOX) has proinflammation enzyme in infection-induced cardiac dysfunction (IICD) and its underlying mechanism.

METHODS

Patients with IICD were collected by our hospital. A mouse model of IICD was induced into male db/db mice by cecal ligation and puncture (CLP). All mice were injected with 20 μL of LV-MIOX or LV-control short hairpin RNA using a 0.5-mL insulin syringe. On the second day, all mice were induced by CLP. H9C2 cell was also induced with lipopolysaccharide and adenosine triphosphate. Quantitative analysis of messenger RNAs (mRNAs) and gene microarray hybridization was used to analyze the mRNA expression levels. Enzyme-linked immunosorbent assay, immunofluorescence, and Western blot analysis were used to analyze the protein expression levels.

RESULTS

The serum expressions of MIOX mRNA level in patients with IICD were upregulated compared to normal healthy volunteers. MIOX promoted inflammation levels in the in vitro model of IICD. Si-MIOX inhibited inflammation levels in the in vitro model of IICD. MIOX accelerated inflammation and cardiac dysfunction in infection-induced mice. MIOX interacted with NLR family pyrin domain containing 3 (NLRP3) protein to reduce the degradation of NLRP3. The inhibition of MIOX reversed the effects of NLRP3 in the in vitro model of cardiac dysfunction.

CONCLUSIONS

Taken together, these findings demonstrate that MIOX accelerates inflammation in the model of IICD, which may be, at least in part, attributable to NLRP3 activity by the suppression of NLRP3 degradation in IICD.

The immunoregulatory role of IL-35 in patients with interstitial lung disease

Pulmonary fibrosis involves various types of immune cells and soluble mediators, including TGF-β and IL-35, a recently identified heterodimeric cytokine that belongs to the IL-12 cytokine family. However, the effect of regulatory IL-35 may play an important role in fibrotic diseases. The aim of this paper is to explore the immunoregulatory role of IL-35 in the development of fibrosis in interstitial lung disease (ILD). To gain a better understanding of this issue, the concentrations of IL-35 and different profibrotic cytokines in fibrotic (F-ILD) and non-fibrotic (NF-ILD) patients by ELISA were compared to that of intracellular IL-35 and IL-17 on CD4+ T cells stimulated in the presence of BAL or with different ratios of recombinant IL-35 (rIL-35) and TGF-β (rTGF-β), which were evaluated by flow cytometry. We observed that BAL concentration of IL-35 was lower in F patients (p < 0.001) and was negatively correlated with concentrations of TGF-β (p < 0.001) and IL-17 (p < 0.001). In supplemented cell cultures, BAL from NF but not F patients enhanced the percentage of IL-35 + CD4+ T (p < 0.001) cells and decreased the percentage of IL-17 + CD4+ T cells (p < 0.001). The percentage of IL-35 + CD4+ T cells correlated positively with BAL concentration of IL-35 (p = 0.02), but correlated negatively with BAL concentrations of IL-17 (p = 0.007) and TGF-β (p = 0.01). After adjusting the concentrations of recombinant cytokines to establish a TGF-β: IL-35 ratio of 1:4, an enhanced percentage of IL-35 + CD4+ T cells (p < 0.001) but a decreased percentage of IL-17 + CD4+ T cells (p < 0.001) was observed. After adding recombinant IL-35 to the BAL from F patients until a 1:4 ratio of TGF-β: IL-35 was reached, a significantly increased percentage of IL-35 + CD4+ T cells (p < 0.001) and a decreased percentage of IL-17 + CD4+ T cells (p = 0.003) was found. These results suggest that IL-35 may induce an anti-fibrotic response, regulating the effect of TGF-β and the inflammatory response on CD4+ T cells. In addition, the TGF-β: IL-35 ratio in BAL has been shown to be a potential biomarker to predict the outcome of F patients with ILD.

The diagnostic value of interleukin 35 as a septic biomarker: A meta-analysis

Background

There is growing evidence that interleukin 35 (IL-35) represents a potential diagnostic biomarker for sepsis. The purpose of this meta-analysis was to evaluate the overall diagnostic accuracy of IL-35 in sepsis.

Materials and methods

From October 1998 to May 2022, set retrieval standards were used to search literature Databases. Each included study was assessed diagnostic accuracy study quality assessment tool. Two researchers independently extracted the data and research features. If there are differences, the issue will be resolved by mutual agreement. Meta-disc and Stata software were utilized to calculate combined sensitivity, specificity, and summary diagnostic odds ratio (SDOR), I2, or Cochrane Q in order to detection for heterogeneity, and meta-regression was performed to figure out the cause of heterogeneity. Utilizing funnel plots, we tested for publication bias.

Results

In this meta-analysis, eight publications were included. The combined sensitivity, specificity, and DOR were 0.87 (95% CI, 0.77–0.93), 0.73 (95% CI, 0.60–0.83), and 18.26 (95% CI, 9.70–34.37), respectively. In addition, 0.88 (95% CI, 0.84–0.90) was the area under the summary receiver operating characteristic curve. In the heterogeneity analysis, the sensitivity of comprehensive I2 statistic was 84.38, and the specificity was 87.82. Deeks’ funnel plot showed no publication bias in this meta-analysis (P = 0.17). A meta-analysis revealed that IL-35 has a modest sensitivity (AUC = 0.88) for diagnosing sepsis. We also compared the diagnostic accuracy of IL-35 and procalcitonin (PCT), and our results showed that the diagnostic accuracy parameters for IL-35 were significantly higher than those for PCT.

Conclusion

Interleukin 35 is a valuable biomarker for the early detection of sepsis. However, the data should be combined with clinical symptoms, signs, and laboratory and microbiological findings.

IL-12p40 deletion aggravates lipopolysaccharide-induced cardiac dysfunction in mice

Background

Cardiac dysfunction is one of the most common complications of sepsis and is associated with the adverse outcomes and high mortality of sepsis patients. IL-12p40, the common subunit of IL-12 and IL-23, has been shown to be involved in a variety of inflammation-related diseases, such as psoriasis and inflammatory bowel disease. However, the role of IL-12p40 in lipopolysaccharide (LPS)-induced cardiac dysfunction remains obscure. This study aimed to explore the role of IL-12p40 in LPS-induced cardiac dysfunction and its potential mechanisms.

Methods

In this study, mice were treated with LPS and the cardiac expression of IL-12p40 was determined. Then, IL-12p40–/– mice were used to detect the role and mechanisms of IL-12p40 in LPS-induced cardiac injury. In addition, monocytes were adoptively transferred to IL-12p40–/– mice to explore their effects on LPS-induced cardiac dysfunction.

Results

The results showed that cardiac IL-12p40 expression was significantly increased after treated with LPS. In addition, IL-12p40 deletion significantly aggravated LPS-induced cardiac dysfunction, evidenced by the increased serum levels of cardiomyocyte injury markers and heart injury scores, as well as by the deteriorated cardiac function. Moreover, IL-12p40 deletion increased LPS-induced monocyte accumulation and cardiac expression of inflammatory cytokines, as well as enhanced the activation of the NF-κB and MAPK pathways. Furthermore, adoptive transfer WT mouse monocytes to IL-12p40−/− mice alleviated LPS-induced cardiac dysfunction and decreased the phosphorylation of p65.

Conclusion

IL-12p40 deletion significantly aggravated LPS-induced cardiac injury and cardiac dysfunction in mice by regulating the NF-κB and MAPK signaling pathways, and this process was related to monocytes. Therefore, IL-12p40 show a protective role in SIC, and IL-12p40 deficiency or anti-IL-12p40 monoclonal antibodies may be detrimental to patients with SIC.

Interleukin-35 ameliorates cardiovascular disease by suppressing inflammatory responses and regulating immune homeostasis

The immune response is of great significance in the initiation and progression of a diversity of cardiovascular diseases involving pro-and anti-inflammatory cytokines. Interleukin-35 (IL-35), a cytokine of the interleukin-12 family, is a novel anti-inflammation and immunosuppressive cytokine, maintaining inflammatory suppression and regulating immune homeostasis. The role of IL-35 in cardiovascular diseases (CVDs) has aroused enthusiastic attention, a diversity of experimental or clinical evidence has indicated that IL-35 potentially has a pivot role in protecting against cardiovascular diseases, especially atherosclerosis and myocarditis. In this review, we initiate an overview of the relationship between Interleukin-35 and cardiovascular diseases, including atherosclerosis, acute coronary syndrome, pulmonary hypertension, abdominal aortic aneurysm, heart failure, myocardial ischemia-reperfusion, aortic dissection and myocarditis. Although the specific molecular mechanisms entailing the protective effects of IL-35 remain an unsolved issue, targeted therapies with IL-35 might provide a promising and effective solution to prevent and cure cardiovascular diseases.

Puerarin protects against sepsis-induced myocardial injury through AMPK-mediated ferroptosis signaling

Objective: Research suggests that Puerarin may protect against sepsis-induced myocardial damage. However, the mechanisms responsible for Puerarin’s cardioprotective effect remain largely unclear. In this study, our objective is to investigate the role of Puerarin-induced AMPK-mediated ferroptosis signaling in protecting myocardial injury.

Methods: 48 male Sprague-Dawley rats were randomly divided into four groups: control group, LPS group, LPS + Pue group, LPS + Pue + Era (Erastin, ferroptosis activator) group, or LPS + Pue + CC (compound C, AMPK inhibitor) group. During the experiment, cardiac systolic function indexes and myocardial histopathological changes were monitored. The serum levels of myocardial injury marker enzyme, inflammatory response related marker enzyme, and oxidative stress related-marker enzyme were measured with ELISA. Apoptotic cardiomyocytes, the iron content in myocardial tissue, apoptosis-related proteins, AMPK, and ferroptosis-related proteins were determined.

Results: Puerarin inhibited the myocardial injury induced by LPS. The cardioprotective effects of Puerarin decreased after adding ferroptosis-activating compound Erastin. The protein expression levels of GPX4 and ferritin were down-regulated, whereas ACSL4, TFR, and heart iron content were up-regulated in LPS + Pue + Era group compared with LPS+Pue group. A significant difference was identified between LPS + Pue + Era group and LPS + Pue group in P-AMPK and T-AMPK levels. Meanwhile, after providing CC, P-AMPK/T-AMPK was significantly reduced, the protein expression levels of GPX4 and ferritin were down-regulated. ACSL4, TFR, and the heart iron content were up-regulated in LPS + Pue + CC group compared to LPS + Pue group.

Conclusions: Puerarin protected against sepsis-induced myocardial injury, and AMPK-mediated ferroptosis signaling played a crucial role in its cardioprotective effect.

Lycorine ameliorates isoproterenol-induced cardiac dysfunction mainly via inhibiting inflammation, fibrosis, oxidative stress and apoptosis

Alleviating cardiac dysfunction improves the prognosis of heart failure patients. Lycorine is an alkaloid with several beneficial biological properties. Here, we used mice to evaluate the effect of lycorine on cardiac dysfunction elicited by isoproterenol. Mice were divided into four groups: control, lycorine, isoproterenol, and isoproterenol + lycorine. Mice in the combined group were treated daily with 10 mg/kg isoproterenol intraperitoneally for 2 weeks and 5 mg/kg lycorine was given simultaneously intraperitoneally for 4 weeks. Cardiac structure and function were assessed by echocardiography, hematoxylin and eosin staining, and Masson's trichrome staining. Isoproterenol-induced cardiac dysfunction and histopathological injury that was significantly improved by treatment with lycorine. Western blotting and the quantitative real-time polymerase chain reaction were used to explore the molecular mechanisms of these effects. Levels of the inflammatory cytokines, interleukin (IL)-1β, IL-6, and tumor necrosis factor-α, were increased by treatment with isoproterenol; these increases were significantly reduced by lycorine, with involvement of the NF-κB signaling pathway. The fibrotic factors, collagen I and collagen III, were increased by isoproterenol and decreased by treatment with lycorine through inhibiting activation of the Smad signaling pathway. In addition, lycorine alleviated oxidative stress as evidenced by a reduction in total reactive oxygen species in the isoproterenol + lycorine group compared to the isoproterenol group. Lycorine exerted an anti-apoptotic effect as evidenced by upregulating Bcl-2 and downregulating Bax. Overall, our findings demonstrate that lycorine protects against cardiac dysfunction induced by isoproterenol by inhibiting inflammation, fibrosis, oxidative stress, and apoptosis.

Dexmedetomidine Promotes Lipopolysaccharide-Induced Differentiation of Cardiac Fibroblasts and Collagen I/III Synthesis through α2A Adrenoreceptor-Mediated Activation of the PKC-p38-Smad2/3 Signaling Pathway in Mice

Dexmedetomidine (DEX), a selective α₂ adrenergic receptor (AR) agonist, is commonly used as a sedative drug during critical illness. In the present study, we explored a novel accelerative effect of DEX on cardiac fibroblast (CF) differentiation mediated by LPS and clarified its potential mechanism. LPS apparently increased the expression of α-SMA and collagen I/III and the phosphorylation of p38 and Smad-3 in the CFs of mice. These effects were significantly enhanced by DEX through increasing α_2A-AR expression in CFs after LPS stimulation. The CFs from α_2A-AR knockout mice were markedly less sensitive to DEX treatment than those of wild-type mice. Inhibition of protein kinase C (PKC) abolished the enhanced effects of DEX on LPS-induced differentiation of CFs. We also found that the α-SMA level in the second-passage CFs was much higher than that in the nonpassage and first-passage CFs. However, after LPS stimulation, the TNF-α released from the nonpassage CFs was much higher than that in the first- and second-passage CFs. DEX had no effect on LPS-induced release of TNF-α and IL-6 from CFs. Further investigation indicated that DEX promoted cardiac fibrosis and collagen I/III synthesis in mice exposed to LPS for four weeks. Our results demonstrated that DEX effectively accelerated LPS-induced differentiation of CFs to myofibroblasts through the PKC-p38-Smad2/3 signaling pathway by activating α_2A-AR.

Interleukin-35 inhibits lipopolysaccharide-induced endothelial cell activation by downregulating inflammation and apoptosis

Inflammation is an essential factor contributing to sepsis-induced endothelial cell (EC) activation. Interleukin-35 (IL-35) is an anti-inflammatory/immunosuppressive cytokine that exerts protective effects on many inflammatory diseases. In this study, we investigated the effects of IL-35 on lipopolysaccharide (LPS)-induced EC activation and the potential underlying mechanism. Human umbilical vein endothelial cells (HUVECs) were incubated with LPS (1 μg/ml) for 24 h and then cocultured with different concentrations (0, 1, 10, or 100 ng/ml) of recombinant human IL-35 (rhIL-35) for 12 h. Flow cytometry analysis revealed that IL-35 inhibited LPS-induced HUVEC apoptosis in a dose-dependent manner. RT-qPCR and Western blot analyses showed significantly higher mRNA and protein levels of the adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and the inflammatory factors IL-6 and IL-8 in the LPS group than in the control group. These changes were alleviated by IL-35 treatment, suggesting that IL-35 protects ECs by downregulating inflammation. Furthermore, IL-35 induced signal transducer and activator of transcription 1 (STAT1) and STAT4 activation and promoted their interaction. Blocking STAT1 or STAT4 expression by fludarabine (STAT1 inhibitor) treatment or siRNA-STAT4-interfering fragment transfection inhibited the protective effect of IL-35 on ECs. Moreover, we observed a similar protective effect of IL-35 treatment on ECs in a mouse sepsis model induced by intraperitoneal LPS injection. This study indicated that IL-35 exerts anti-inflammatory and antiapoptotic effects on LPS-induced EC activation by activating the STAT1 and STAT4 signaling pathways.

Ghrelin Alleviates Intestinal Dysfunction in Sepsis Through the KLF4/MMP2 Regulatory Axis by Activating SIRT1

Intestinal barrier dysfunction is an important contributor to morbidity caused by sepsis. This study investigates the molecular mechanism by which Ghrelin affects intestinal dysfunction in rat model of sepsis. A rat model of sepsis was established by cecal ligation and puncture (CLP), revealing that Ghrelin was downregulated when sepsis occurs. Increases in the levels of inflammatory factors tumor necrosis factor α (TNF-α), interleukin-1 (IL-1β), IL-6, gastrin, γ-H2AX and 8-OHdG was also detected in this model system, as was an overall increase in oxidative stress. Introduction of exogenous Ghrelin inhibited these increases in inflammatory response and oxidative stress, leading to a reduction of overall sepsis-induced intestinal dysfunction. Ghrelin was then shown to activate SIRT1 expression in vitro, while SIRT1 was found to co-express with KLF4, which in turn was predicted to bind to matrix metalloproteinase 2 (MMP2) promoter. Finally, gain- and loss-of-function experiment demonstrated that SIRT1 upregulated the expression of KLF4 to downregulate MMP2. Collectively, Ghrelin inhibits the oxidative stress and intestinal dysfunction to attenuate sepsis by activating SIRT1 and regulating a KLF4/MMP2 regulatory axis.

Early Passive Leg Movement Prevents Against the Development of Heart Failure With Preserved Ejection Fraction in Rats

Exercising was reported by several studies to bring great benefits to heart failure with preserved ejection fraction (HFpEF), which reduced the hospitalization and the mortality of heart failure. However, the underlying mechanism of exercising on HFpEF remains unclear. In the present study, we designed and constructed a device that can perform early passive leg movement (ePLM) in rats and further observed whether treatment of ePLM exerts protective effects on HFpEF of rats. Rats were fed with high salt feed to establish an animal model of pre-clinical diastolic dysfunction (PDD), which would eventually develop into HFpEF, and then treated rats with ePLM. We conducted several experiments to evaluate the conditions of heart and blood vessel. The results show that diastolic functions of heart and blood vessel in rats were significantly improved by treatment of ePLM. We also found that pathological injuries of heart and blood vessel were ameliorated after treatment of ePLM. Moreover, treatment of ePLM decreased the protein levels of Collagen type I, Collagen type III, MMP2, and MMP9 in heart and blood vessel, indicating that cardiac and vascular fibrosis were reduced apparently by treatment of ePLM. Further investigation suggested that treatment of ePLM probably inhibit the activation of TGF-β1/Smad3 signaling pathway as well as promote the activation of Akt/eNOS signaling pathway in high salt diet induced HFpEF. In conclusion, treatment of ePLM alleviated high salt diet induced HFpEF by inhibiting fibrosis via suppressing TGF-β1/Smad3 signaling pathway as well as activating Akt/eNOS signaling pathway, implicating treatment of ePLM as a promising novel non-pharmacological approach for HFpEF.

Astragaloside IV-targeting miRNA-1 attenuates lipopolysaccharide-induced cardiac dysfunction in rats through inhibition of apoptosis and autophagy

Astragaloside IV (AS-IV), the major active constituent purified from Astragalus membranaceus, was previously reported to have protective effects against cardiac dysfunction. However, the underlying mechanism remains unknown. In the present study, we investigated the protective effect of AS-IV on lipopolysaccharide (LPS)-induced cardiac dysfunction and explored the potential mechanism by focusing on miRNA-1 (miR-1) at the animal and cellular levels. A series of methods were used, including echocardiography, flow cytometry, ELISA, immunofluorescence, transmission electron microscopy, RT-PCR, and western blotting. The results showed that both AS-IV and the miR-1 inhibitor improved cardiac dysfunction, reduced heart injury, inhibited apoptosis and autophagy, and regulated the expression of calcium- and mitochondrial energy metabolism-related proteins in the heart tissue of rats treated with LPS. Importantly, AS-IV downregulated the expression of miR-1 mRNA in heart tissue. All effects of AS-IV were at least partly abolished by miR-1 mimics. In the in vitro study, both AS-IV and the miR-1 inhibitor inhibited apoptosis and autophagy and regulated the expression of calcium- and mitochondrial energy metabolism-related proteins in heart cells treated with LPS. Similarly, AS-IV downregulated the expression of miR-1 mRNA in heart cells. All effects of AS-IV on cells were at least partly abolished by miR-1 mimics. Furthermore, miR-1 mimics exhibited effects similar to LPS both in animal and cellular studies. Taken together, these results suggest that AS-IV protects against LPS-induced cardiac dysfunction by inhibiting calcium-mediated apoptosis and autophagy by targeting miR-1, highlighting a new mechanism for the therapeutic effect of AS-IV on cardiac dysfunction.

Sacubitril/Valsartan Reduces Fibrosis and Alleviates High-Salt Diet-Induced HFpEF in Rats

Previous studies have confirmed the clinical efficacy of sacubitril/valsartan (Sac/Val) for the treatment of heart failure with reduced ejection fraction (HFrEF). However, the role of Sac/Val in heart failure with preserved ejection fraction (HFpEF) remains unclear. Sac/Val is a combination therapeutic medicine comprising sacubitril and valsartan that acts as a first angiotensin receptor blocker and neprilysin inhibitor (angiotensin-receptor neprilysin inhibitor (ARNI)). Here, we investigated the role of Sac/Val in high-salt diet-induced HFpEF coupled with vascular injury as well as the underlying mechanism. Rats were fed with high-salt feed, followed by intragastric administration of Sac/Val (68 mg/kg; i.g.). The results of functional tests revealed that a high-salt diet caused pathological injuries in the heart and vascular endothelium, which were significantly reversed by treatment with Sac/Val. Moreover, Sac/Val significantly decreased the levels of fibrotic factors, including type I collagen and type Ⅲ collagen, thus, reducing the ratio of MMP2/TIMP2 while increasing Smad7 levels. Further investigation suggested that Sac/Val probably reversed the effects of high-salt diet-induced HFpEF by inhibiting the activation of the TGF-β1/Smad3 signaling pathway. Thus, treatment with Sac/Val effectively alleviated the symptoms of high-salt diet-induced HFpEF, probably by inhibiting fibrosis via the TGF-β1/Smad3 signaling pathway, supporting the therapeutic potential of Sac/Val for the treatment of HFpEF.