microRNA-193-3p attenuates myocardial injury of mice with sepsis via STAT3/HMGB1 axis

Snhg14/miR-181a-5p axis-mediated "M1" macrophages aggravate LPS-induced myocardial cell injury

An increasing number of studies have suggested that macrophages participate in sepsis-induced myocardial injury. Our study highlights the function and mechanism of the lncRNA Snhg14 in "M1" polarized macrophage-mediated myocardial cell damage. Lipopolysaccharide (LPS) was used to treat H9c2 cells to construct an in vitro myocardial injury model. M1 and M2 polarization of RAW264.7 cells were induced and the exosomes were obtained from the supernatant through ultracentrifugation. Moreover, cecal ligation and puncture (CLP) surgery was implemented to establish a mouse sepsis-induced myocardial injury model, and Snhg14 was knocked down with sh-Snhg14. The results showed that the conditioned medium (CM) and the exosomes (Exo) of M1 macrophages substantially augmented LPS-induced apoptosis and oxidative stress in myocardial cells. Notably, M1-CM and M1-Exo contributed to nearly 50 % of myocardial cell viability decline. Snhg14 was highly expressed in M1 macrophages and exosomes derived from M1-MΦ (M1-Exo). Snhg14 overexpression aggravated myocardial cell damage and increased 10 to 50 times expression of proinflammatory cytokines in MΦ. Snhg14 knockdown reversed M1-Exo-mediated myocardial cell damage and inhibited the production of proinflammatory cytokines (50 %-75 % decline) of MΦ. Moreover, Snhg14 targeted and inhibited miR-181a-5p expression. miR-181a-5p upregulation partly reversed Snhg4 overexpression-mediated myocardial cell damage and MΦ activation. In vivo, sh-Snhg14 dramatically ameliorated cardiac damage in septic mice by enhancing miR-181a-5p and inhibiting the HMGB1/NF-κB pathway. In conclusion, "M1" macrophage-derived exosomal Snhg14 aggravates myocardial cell damage by modulating the miR-181a-5p/HMGB1/NF-κB pathway.

Chronic kidney disease and left ventricular diastolic dysfunction (CKD-LVDD) alter cardiac expression of mitochondria-related genes in swine

Cardiovascular disease and heart failure doubles in patients with chronic kidney disease (CKD), but the underlying mechanisms remain obscure. Mitochondria are central to maintaining cellular respiration and modulating cardiomyocyte function. We took advantage of our novel swine model of CKD and left ventricular diastolic dysfunction (CKD-LVDD) to investigate the expression of mitochondria-related genes and potential mechanisms regulating their expression. CKD-LVDD and normal control pigs (n=6/group, 3 males/3 females) were studied for 14 weeks. Renal and cardiac hemodynamics were quantified by multidetector-CT, echocardiography, and pressure-volume loop studies, respectively. Mitochondrial morphology (electron microscopy) and function (Oroboros) were assessed ex vivo. In randomly selected pigs (n=3/group), cardiac mRNA-, MeDIP-, and miRNA-sequencing (seq) were performed to identify mitochondria-related genes and study their pre- and post -transcriptional regulation. CKD-LVDD exhibited cardiac mitochondrial structural abnormalities and elevated mitochondrial H2O2 emission but preserved mitochondrial function. Cardiac mRNA-seq identified 862 mitochondria-related genes, of which 69 were upregulated and 33 downregulated (fold-change ≥2, false discovery rate≤0.05). Functional analysis showed that upregulated genes were primarily implicated in processes associated with oxidative stress, whereas those downregulated mainly participated in respiration and ATP synthesis. Integrated mRNA/miRNA/MeDIP-seq analysis showed that upregulated genes were modulated predominantly by miRNAs, whereas those downregulated were by miRNA and epigenetic mechanisms. CKD-LVDD alters cardiac expression of mitochondria-related genes, associated with mitochondrial structural damage but preserved respiratory function, possibly reflecting intrinsic compensatory mechanisms. Our findings may guide the development of early interventions at stages of cardiac dysfunction in which mitochondrial injury could be prevented, and the development of LVDD ameliorated.

miR-29b-1-5p exacerbates myocardial injury induced by sepsis in a mouse model by targeting TERF2

Myocardial damage is a critical complication and a significant contributor to mortality in sepsis. MicroRNAs (miRNAs) have emerged as key players in sepsis pathogenesis. In this study, we explore the effect and mechanisms of miR-29b-1-5p on sepsis-induced myocardial damage. Sepsis-associated Gene Expression Omnibus datasets (GSE72380 and GSE29914) are examined for differential miRNAs. The mouse sepsis-induced cardiac injury was established by Lipopolysaccharide (LPS) or cecal ligation and puncture (CLP). LPS-treated HL-1 mouse cardiomyocytes simulate myocardial injury in vitro. miR-29b-1-5p is co-upregulated in both datasets and in cardiac tissue from sepsis mouse and HL-1 cell models. miR-29b-1-5p expression downregulation was achieved by antagomir transduction and confirmed by real-time quantitative reverse transcription PCR. Survival analysis and echocardiography examination show that miR-29b-1-5p inhibition improves mice survival cardiac function in LPS- and CLP-induced sepsis mice. Hematoxylin and eosin and Masson's trichrome staining and Immunohistochemistry analysis of mouse myocardial α-smooth muscle actin show that miR-29b-1-5p inhibition reduces myocardial tissue injury and fibrosis. The inflammatory cytokines and cardiac troponin I (cTnI) levels in mouse serum and HL-1 cells are also decreased by miR-29b-1-5p inhibition, as revealed by enzyme-linked immunosorbent assay. The expressions of autophagy-lysosomal pathway-related and apoptosis-related proteins in the mouse cardiac tissues and HL-1 cells are evaluated by western blot analysis. The sepsis-induced activation of the autophagy-lysosomal pathway and apoptosis are also reversed by miR-29b-1-5p antagomir. MTT and flow cytometry measurement further confirm the protective role of miR-29b-1-5p antagomir in HL-1 cells by increasing cell viability and suppressing cell apoptosis. Metascape functionally enriches TargetScan-predicted miR-29b-1-5p target genes. TargetScan prediction and dual luciferase assay validate the targeting relationship between miR-29b-1-5p and telomeric repeat-binding factor 2 (TERF2). The expression and function of TERF2 in HL-1 cells and mice are also evaluated. MiR-29b-1-5p negatively regulates the target gene TERF2. TERF2 knockdown partly restores miR-29b-1-5p antagomir function in LPS-stimulated HL-1 cells. In summary, miR-29b-1-5p targetedly inhibits TERF2, thereby enhancing sepsis-induced myocardial injury.

Long noncoding RNA MCM3AP-AS1 attenuates sepsis-induced cardiomyopathy by improving inflammation, oxidative stress, and mitochondrial function through mediating the miR-501-3p/CADM1/STAT3 axis

Oxidative stress and inflammation are highly important for sepsis-mediated myocardial damage. The long noncoding RNA (lncRNA) MCM3AP-AS1 is involved in inflammatory diseases, but its function in acute myocardial injury during sepsis has not been fully elucidated. LPS and cecal ligation and puncture (CLP) were used to construct in vitro and in vivo sepsis-induced myocardial damage models, respectively. qRT-PCR was used to evaluate alterations in MCM3AP-AS1 and miR-501-3p alterations. After the MCM3AP-AS1 and miR-501-3p knockdown or overexpression models were established, the viability, apoptosis, inflammation, oxidative stress, and mitochondrial function of the myocardial cells were examined. Dual luciferase activity assay, RNA immunoprecipitation, and fluorescence in situ hybridization (FISH) confirmed the correlation among MCM3AP-AS1, miR-501-3p, and CADM1. Previous studies revealed that MCM3AP-AS1 was downregulated in sepsis patients, myocardial cells treated with LPS, and in the CLP mouse sepsis model, whereas miR-501-3p expression was increased. MCM3AP-AS1 overexpression hampered myocardial damage mediated by LPS and abated inflammation, oxidative stress, and mitochondrial dysfunction in myocardial cells and THP-1 cells. In contrast, MCM3AP-AS1 knockdown or miR-501-3p overexpression promoted all the effects of LPS. In vivo, MCM3AP-AS1 overexpression increased the survival rate of CLP mice; ameliorated myocardial injury; decreased the levels of TNF-α, IL-1β, IL-6, iNOS, COX2, ICAM1, VCAM1, PGE2, and MDA; and increased the levels of SOD, GSH-PX, Nrf2, and HO-1. Mechanistic studies demonstrated that MCM3AP-AS1 acted as a competitive endogenous RNA to repress miR-501-3p, enhance CADM1 expression, and dampen STAT3/nuclear factor-kappaB (NF-κB) activation. MCM3AP-AS1 suppresses myocardial injury elicited by sepsis by mediating the miR-501-3p/CADM1/STAT3/NF-κB axis.

Extracellular Vesicles Derived from Human Adipose-Derived Mesenchymal Stem Cells Alleviate Sepsis-Induced Acute Lung Injury through a MicroRNA-150-5p-Dependent Mechanism

Extracellular vesicles (EVs) derived from human adipose mesenchymal stem cells (hADSCs) may exert a therapeutic benefit in alleviating sepsis-induced organ dysfunction by delivering cargos that include RNAs and proteins to target cells. The current study aims to explore the protective effect of miR-150-5p delivered by hADSC-EVs on sepsis-induced acute lung injury (ALI). We noted low expression of miR-150-5p in plasma and bronchoalveolar lavage fluid samples from patients with sepsis-induced ALI. The hADSC-EVs were isolated and subsequently cocultured with macrophages. It was established that hADSC-EVs transferred miR-150-5p to macrophages, where miR-150-5p targeted HMGA2 to inhibit its expression and, consequently, inactivated the MAPK pathway. This effect contributed to the promotion of M2 polarization of macrophages and the inhibition of proinflammatory cytokines. Further, mice were made septic by cecal ligation and puncture in vivo and treated with hADSC-EVs to elucidate the effect of hADSC-EVs on sepsis-induced ALI. The in vivo experimental results confirmed a suppressive role of hADSC-EVs in sepsis-induced ALI. Our findings suggest that hADSC-EV-mediated transfer of miR-150-5p may be a novel mechanism underlying the paracrine effects of hADSC-EVs on the M2 polarization of macrophages in sepsis-induced ALI.

Evaluation of circulating levels of miR-135a and miR-193 in patients with sepsis

BACKGROUND

Sepsis is a life-threatening condition where early diagnosis and prognostic awareness provide guidance for selecting the appropriate treatment strategies. A wide variety of biomarker-based studies in clinical medicine provide new insights into personalized medicine for sepsis patients. MiRNAs are endogenous non-coding RNA molecules that have been acting as great potential diagnostic, prognostic and therapeutic biomarkers in various diseases.

METHODS AND RESULTS

In the present study, the expression levels of two selected miRNAs, including miR-135a and miR-193, were evaluated for their prognostic potential in patients with sepsis. The circulating levels of miRNAs were quantified by quantitative PCR (qPCR) in patients with sepsis (n = 100) and age- and sex-matched healthy controls (n = 100). Statistical findings confirmed the valuable prognostic potential of miR-135a in patients with sepsis, while no significant difference was found between the miR-193 expression level in the patients with sepsis and the controls.

CONCLUSIONS

Circulating levels of miRNA-135a can serve a the prognostic biomarker for patients with sepsis. These findings highlight the importance of miRNAs as signatures in the personalized managements of sepsis.

Echinacoside Prevents Sepsis-Induced Myocardial Damage via Targeting SOD2

Echinacoside (ECH) is a prominent naturally occurring bioactive compound with effects of alleviating myocardial damage. We aimed to explore the beneficial effects of ECH against sepsis-induced myocardial damage and elucidate the potential mechanism. Echocardiography and Masson staining demonstrated that ECH alleviates cardiac function and fibrosis in the cecal ligation and puncture (CLP) model. Transcriptome profiling and network pharmacology analysis showed that there are 51 overlapping targets between sepsis-induced myocardial damage and ECH. Subsequently, chemical carcinogenesis-reactive oxygen species (ROS) were enriched in multiple targets. Wherein, SOD2 may be the potential target of ECH on sepsis-induced myocardial damage. Polymerase chain reaction results showed that ECH administration could markedly increase the expression of SOD2 and reduce the release of ROS. Combined with injecting the inhibitor of SOD2, the beneficial effect of ECH on mortality, cardiac function, and fibrosis was eliminated, and release of ROS was increased after inhibiting SOD2. ECH significantly alleviated myocardial damage in septic mice, and the therapeutic mechanism of ECH is achieved by upregulating SOD2 which decreased the release of ROS.

MiR-2113 overexpression attenuates sepsis-induced acute pulmonary dysfunction, inflammation and fibrosis by inhibition of HMGB1

Purpose

Sepsis-induced acute lung injury is related to high mortality. MiR-2113 possesses important functions in human diseases. This research aimed to clarify the role and mechanism of miR-2113 in sepsis-induced acute lung injury.

Methods

The expression of miR-2113 in lipopolysaccharide (LPS)-induced MLE-12 cells, serum of sepsis patients, and cecal ligation and puncture mouse models was examined using quantitative real-time PCR. The functions of miR-2113 in LPS-treated MLE-12 cells were estimated by Cell Counting Kit-8 assay, flow cytometry, enzyme-linked immunosorbent assay, Western blot, and immunofluorescence. The influences of miR-2113 in cecal ligation and puncture-induced acute lung injury in mice were assessed by hematoxylin-eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay, acute pulmonary dysfunction analysis, lactate dehydrogenase levels and total protein concentrations in bronchoalveolar lavage fluid, and Masson staining. Also, the mechanism of miR-2113 was examined using a dual-luciferase reporter assay.

Results

MiR-2113 expression was decreased in LPS-induced MLE-12 cells, serum of sepsis patients, and cecal ligation and puncture mouse models. miR-2113 overexpression restored LPS-reduced MLE-12 cell proliferation, but alleviated LPS-induced apoptosis and markers of inflammation and fibrosis in MLE-12 cells. Moreover, we found that miR-2113 mimic reduced LPS-induced MLE-12 cell injury by negatively regulating high-mobility group box 1. In vivo data further confirmed that miR-2113 overexpression alleviated acute pulmonary dysfunction, inflammation and fibrosis in cecal ligation and puncture-induced sepsis mice.

Conclusion

MiR-2113 relieved sepsis-induced acute pulmonary dysfunction, inflammation and fibrosis through decreasing high-mobility group box 1.

IFITM3 overexpression reverses insufficient healing benefits of small extracellular vesicles from high-fat-diet BMSCs in sepsis via the HMGB1 pathway

Bone marrow mesenchymal stem cells (BMSCs) are a promising new therapy for sepsis, a common cause of death in hospitals. However, the global epidemic of metabolic syndromes, including obesity and pre-obesity, threatens the health of the human BMSC pool. The therapeutic effects of BMSCs are primarily due to the secretion of the small extracellular vesicles containing lipids, proteins, and RNA. Accordingly, studies on BMSCs, their small extracellular vesicles, and their modifications in obese individuals are becoming increasingly important. In this study, we investigated the therapeutic potential of small extracellular vesicles (sEVs) from high-fat diet BMSCs (sEVsHFD) in sepsis-induced liver-heart axis injury. We found that sEVsHFD yielded diminished therapeutic benefits compared to sEVs from chow diet BMSCs (sEVsCD). We subsequently verified that IFITM3 significantly differed in sEVsCD and sEVsHFD, alternating in septic liver tissue, and indicating its potential as a remodeling target of sEVs. IFITM3-overexpressed high-fat-diet BMSCs (HFD-BMSCs) showed that corresponding sEVs (sEVsHFD-IFITM3) markedly ameliorated liver-heart axis injury during sepsis. Lastly, we identified the protective action mechanisms of sEVsHFD-IFITM3 in sepsis-induced organ failure and HMGB1 expression and secretion was altered in septic liver and serum while HMGB1 has been demonstrated as a critical mediator of multi-organ failure in sepsis. These findings indicate that IFITM3 overexpression regenerates the therapeutic benefit of sEVs from HFD-BMSCs in sepsis via the HMGB1 pathway.

SNHG1/miR-21 axis mediates the cardioprotective role of aloin in sepsis through modulating cardiac cell viability and inflammatory responses

BACKGROUND

Aloin has cardioprotective effects, however, its cardioprotective role in sepsis remains unclear. This study aimed to analyze whether aloin could prevent sepsis-related myocardial damage and explore the underlying mechanisms by examining the expression of long-noncoding RNA (lncRNA) SNHG1 and microRNA-21 (miR-21).

METHODS

The interaction of SNHG1 with miR-21 was identified by dual-luciferase reporter assay. The levels of SNHG1 and miR-21 were measured by real-time quantitative PCR. The cardioprotective function of aloin was assessed in a sepsis animal model, which was induced by cecal ligation and puncture, and in a myocardial injury cell model in H9C2 cells stimulated by lipopolysaccharide. Myocardial injury biomarker levels and hemodynamic indicators in mice model were measured to evaluate cardiac function. The viability of H9C2 cells was assessed by cell counting kit-8 assay. Inflammatory cytokine levels were examined by an ELISA method.

RESULTS

Decreased SNHG1 and increased miR-21 were found in sepsis patients with cardiac dysfunction, and they were negatively correlated. Aloin significantly attenuated myocardial damage and inflammatory responses of mice model, and increased the viability and suppressed inflammation in H9C2 cell model. In addition, SNHG1 expression was upregulated and miR-21 expression was downregulated by aloin in both mice and cell models. Moreover, in mice and cell models, SNHG1/miR-21 axis affected sepsis-related myocardial damage, and mediated the cardioprotective effects of aloin.

CONCLUSION

Our findings indicated that aloin exerts protective effects in sepsis-related myocardial damage through regulating cardiac cell viability and inflammatory responses via regulating the SNHG1/miR-21 axis.

Matrine Alleviates Sepsis-Induced Myocardial Injury by Inhibiting Ferroptosis and Apoptosis

Matrine is a Sophora alkaloid that exerts antitumor effects on a variety of diseases, but few studies have investigated the role of matrine in sepsis-induced myocardial injury. In the present study, we investigated the effects of matrine on septic myocardial injury and the potential mechanisms. Network pharmacology approaches were used to predict the targets of matrine in the treatment of sepsis-induced myocardial injury. A mouse sepsis-induced myocardial injury model was established to determine the effect of matrine. Mouse cardiac function was evaluated by ultrasonography, and cardiac morphology and cardiomyocyte apoptosis were evaluated by HE and TUNEL staining. Oxidative stress was assessed by measuring ROS levels and MDA and SOD activity. Bax, Bcl2, GPX4, ACSL4, PI3K, and AKT protein levels were evaluated by immunohistochemical staining and western blotting. Bioinformatics analysis identified that the potential therapeutic effect of matrine on sepsis-induced myocardial injury is closely related to ferroptosis and apoptosis regulation and showed significant involvement of the PI3K/AKT signaling pathway. In vivo, the matrine group showed improved myocardial function, morphology, and apoptosis ratio and alleviated oxidative stress compared with the LPS group, whereas 25 mg/kg matrine exerted the optimal inhibitory effect. Matrine alleviated LPS-induced cardiomyocyte ferroptosis and apoptosis, resulting in upregulation of Bax/Bcl2 and GPX4 expression and downregulation of ferroptosis marker protein (ACSL4) expression, as shown by immunohistochemistry and western blotting. Moreover, matrine increased PI3K/AKT pathway-related molecule expression and thus modulated ferroptosis and apoptosis. Matrine regulates PI3K/AKT pathway activity to inhibit apoptosis and ferroptosis and thereby alleviates sepsis-induced myocardial injury.

Downregulation of TRIM27 alleviates hypoxic-ischemic encephalopathy through inhibiting inflammation and microglia cell activation by regulating STAT3/HMGB1 axis

TRIM27 expression was increased in the Parkinson's disease (PD), and knockdown of TRIM27 in PC12 cells significantly inhibited cell apoptosis, indicating that downregulation of TRIM27 exerts a neuroprotective effect. Herein, we investigated TRIM27 role in hypoxic-ischemic encephalopathy (HIE) and the underlying mechanisms. HIE models were constructed in newborn rats using hypoxic ischemic (HI) treatment and PC-12/BV2 cells with oxygen glucose deprivation (OGD), respectively. The results demonstrated that TRIM27 expression was increased in the brain tissues of HIE rats and OGD-treated PC-12/BV2 cells. Downregulation of TRIM27 reduced the brain infarct volume, inflammatory factor levels and brain injury, as well as decreased the number of M1 subtype of microglia cells while increased the number of M2 microglia cells. Moreover, deletion of TRIM27 expression inhibited the expression of p-STAT3, p-NF-κB and HMGB1 in vivo and in vitro. In addition, overexpression of HMGB1 impaired the effects of TRIM27 downregulation on improving OGD-induced cell viability, inhibiting inflammatory reactions and microglia activation. Collectively, this study revealed that TRIM27 was overexpressed in HIE, and downregulation of TRIM27 could alleviate HI-induced brain injury through repressing inflammation and microglia cell activation via the STAT3/HMGB1 axis.

Specific microRNA Signature Kinetics in Porphyromonas gingivalis-Induced Periodontitis

Porphyromonas gingivalis is one of the major bacteria constituting the subgingival pathogenic polymicrobial milieu during periodontitis. Our objective is to determine the global microRNA (miRNA, miR) expression kinetics in 8- and 16-weeks duration of P. gingivalis infection in C57BL/6J mice and to identify the miRNA signatures at specific time-points in mice. We evaluated differential expression (DE) miRNAs in mandibles (n = 10) using high-throughput NanoString nCounter® miRNA expression panels. The bacterial colonization, alveolar bone resorption (ABR), serum immunoglobulin G (IgG) antibodies, and bacterial dissemination were confirmed. In addition, all the infected mice showed bacterial colonization on the gingival surface, significant increases in ABR (p < 0.0001), and specific IgG antibody responses (p < 0.05-0.001). The miRNA profiling showed 26 upregulated miRNAs (e.g., miR-804, miR-690) and 14 downregulated miRNAs (e.g., miR-1902, miR-1937a) during an 8-weeks infection, whereas 7 upregulated miRNAs (e.g., miR-145, miR-195) and one downregulated miR-302b were identified during a 16-weeks infection. Both miR-103 and miR-30d were commonly upregulated at both time-points, and all the DE miRNAs were unique to the specific time-points. However, miR-31, miR-125b, miR-15a, and miR-195 observed in P. gingivalis-infected mouse mandibles were also identified in the gingival tissues of periodontitis patients. None of the previously identified miRNAs reported in in vitro studies using cell lines (periodontal ligament cells, gingival epithelial cells, human leukemia monocytic cell line (THP-1), and B cells) exposed to P. gingivalis lipopolysaccharide were observed in the in vivo study. Most of the pathways (endocytosis, bacterial invasion, and FcR-mediated phagocytosis) targeted by the DE miRNAs were linked with bacterial pathogen recognition and clearance. Further, eighteen miRNAs were closely associated with the bacterial invasion of epithelial cells. This study highlights the altered expression of miRNA in gingiva, and their expression depends on the time-points of infection. This is the first in vivo study that identified specific signature miRNAs (miR-103 and miR-30d) in P. gingivalis invasion of epithelial cells, establishes a link between miRNA and development of periodontitis and helping to better understand the pathobiology of periodontitis.

lncR-GAS5 upregulates the splicing factor SRSF10 to impair endothelial autophagy, leading to atherogenesis

Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

Identification of PIK3CG as a hub in septic myocardial injury using network pharmacology and weighted gene co-expression network analysis

Sepsis causes multiple organ injuries, among which the heart is one most severely damaged organ. Melatonin (MEL) alleviates septic myocardial injury, although a systematic and comprehensive approach is still lacking to understand the precise protective machinery of MEL. This study aimed to examine the underlying mechanisms of MEL on improvement of septic myocardial injury at a systematic level. This study integrated three analytic modalities including database investigations, RNA-seq analysis, and weighted gene co-expression network analysis (WCGNA), in order to acquire a set of genes associated with the pathogenesis of sepsis. The Drugbank database was employed to predict genes that may serve as pharmacological targets for MEL-elicited benefits, if any. A pharmacological protein-protein interaction network was subsequently constructed, and 66 hub genes were captured which were enriched in a variety of immune response pathways. Notably, PIK3CG, one of the hub genes, displayed high topological characteristic values, strongly suggesting its promise as a novel target for MEL-evoked treatment of septic myocardial injury. Importantly, molecular docking simulation experiments as well as in vitro and in vivo studies supported an essential role for PIK3CG in MEL-elicited effect on septic myocardial injury. This study systematically clarified the mechanisms of MEL intervention in septic myocardial injury involved multiple targets and multiple pathways. Moreover, PIK3CG-governed signaling cascade plays an important role in the etiology of sepsis and septic myocardial injury. Findings from our study provide valuable information on novel intervention targets for the management of septic myocardial injury. More importantly, this study has indicated the utility of combining a series of techniques for disease target discovery and exploration of possible drug targets, which should shed some light on elucidation of experimental and clinical drug action mechanisms systematically.

High Mobility Group Proteins in Sepsis

Sepsis, a systemic inflammatory response disease, is the most severe complication of infection and a deadly disease. High mobility group proteins (HMGs) are non-histone nuclear proteins binding nucleosomes and regulate chromosome architecture and gene transcription, which act as a potent pro-inflammatory cytokine involved in the delayed endotoxin lethality and systemic inflammatory response. HMGs increase in serum and tissues during infection, especially in sepsis. A growing number of studies have demonstrated HMGs are not only cytokines which can mediate inflammation, but also potential therapeutic targets in sepsis. To reduce sepsis-related mortality, a better understanding of HMGs is essential. In this review, we described the structure and function of HMGs, summarized the definition, epidemiology and pathophysiology of sepsis, and discussed the HMGs-related mechanisms in sepsis from the perspectives of non-coding RNAs (microRNA, long non-coding RNA, circular RNA), programmed cell death (apoptosis, necroptosis and pyroptosis), drugs and other pathophysiological aspects to provide new targets and ideas for the diagnosis and treatment of sepsis.

Down-regulated HDAC1 and up-regulated microRNA-124-5p recover myocardial damage of septic mice

Studies have revealed the relationship between histone deacetylases (HDACs)/microRNAs (miRNAs) and sepsis, but little has ever investigated the mechanism of HDAC1/miR-124-5p in sepsis. Herein, we studied the impacts of HDAC1/miR-124-5p on myocardial damage of septic mice via regulating high-mobility group box chromosomal protein 1 (HMGB1). Septic mice were induced by cecal ligation and puncture. HDAC1, miR-124-5p and HMGB1 expression in myocardial tissues of septic mice were detected. Septic mice were injected with HDAC1 low expression-, miR-124-5p high expression- or HMGB1 low expression-related structures to observe cardiac function, inflammatory response, oxidative stress response, myocardial pathological changes and apoptosis in myocardial tissues of septic mice. The relationship of HDAC1/miR-124-5p/HMGB1 was verified. HDAC1 and HMGB1 expression were upregulated while miR-124-5p expression was decreased in myocardial tissues of septic mice. Restored miR-124-5p/depleted HDAC1 or HMGB1 recovered the cardiac function, improved cardiac function, inflammatory response, oxidative stress response, myocardial pathological changes and inhibit ed cardiomyocyte apoptosis in septic mice. HDAC1 bound to miR-124-5p which directly targeted HMGB1. This study suggests that down-regulated HDAC1 or up-regulated miR-124-5p recovers myocardial damage of septic mice via decreasing HMGB1.