Valproic acid attenuates sepsis-induced myocardial dysfunction in rats by accelerating autophagy through the PTEN/AKT/mTOR pathway

JAK2 inhibitor protects the septic heart through enhancing mitophagy in cardiomyocytes

Sepsis-induced myocardial dysfunction (SIMD) is a severe complication in sepsis, manifested as myocardial systolic dysfunction, which is associated with poor prognosis and higher mortality. Mitophagy, a self-protective mechanism maintaining cellular homeostasis, plays an indispensable role in cardioprotection. This study aimed to unveil the cardioprotective effects of Baricitinib on LPS-induced myocardial dysfunction and its effect on mitophagy. Herein, we demonstrated that LPS induced severe myocardial dysfunction and initiated mitophagy in septic mice hearts. Despite the initiation of mitophagy, a significant number of apoptotic cells and damaged mitochondria persisted in the myocardium, and myocardial energy metabolism remained impaired, indicating that the limited mitophagy was insufficient to mitigate LPS-induced damage. The JAK2-AKT-mTOR signaling pathway is activated in LPS-induced cardiomyocytes and in the hearts of septic mice. Baricitinib administration remarkably improved cardiac function, suppressed systemic inflammatory response, attenuated histopathological changes, inhibited cardiac cell apoptosis and alleviated myocardial damage in septic mice. Furthermore, Baricitinib treatment significantly enhanced PINK1-Parkin-mediated mitophagy, increased autophagosomes, decreased impaired mitochondria, and restored myocardial energy metabolism. Mechanically, the limited mitophagy in septic myocardium was associated with increased p-ULK1 (Ser757), which was regulated by p-mTOR. Baricitinib reduced p-ULK1 (Ser757) and enhanced mitophagy by inhibiting the JAK2-AKT-mTOR signaling pathway. Inhibition of mitophagy with Mdivi-1 reversed the cardiac protective and anti-inflammatory effects of Baricitinib in septic mice. These findings suggest that Baricitinib attenuates SIMD by enhancing mitophagy in cardiomyocytes via the JAK2-AKT-mTOR signaling pathway, providing a novel mechanistic and therapeutic insight into the SIMD.

Identification of potential biomarkers for sepsis based on neutrophil extracellular trap-related genes

Sepsis is a highly lethal disease that poses a serious threat to human health. Increasing evidence indicates that neutrophil extracellular traps (NETs) are key factors in the pathological progression of sepsis. This study aims to screen potential biomarkers for sepsis and delve into their regulatory function in the pathogenesis. We downloaded 6 microarray datasets from the Gene Expression Omnibus (GEO) database, with 4 as the training sets and 2 as the validation sets. NETs-related genes (NRGs) were obtained from relevant literature. Differential expression analysis was performed on four training sets separately. We intersected differentially expressed genes (DEGs) from the four training sets and NRGs, finally resulting in 19 NETs-related sepsis genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) unearthed that NETs-related sepsis genes were majorly abundant in functions and pathways such as defense response to bacterium and Neutrophil extracellular trap formation. Using the PPI network, the MCC algorithm, and the MCODE algorithm in the CytoHubba plugin, 7 sepsis hub genes (ELANE, TLR4, MPO, PADI4, CTSG, MMP9, S100A12) were identified. ROC curve for each Hub gene in the training and validation sets were plotted, which revealed that the Area Under Curve (AUC) values are all greater than 0.6, indicating good classification ability. A total of 349 miRNAs targeting Hub genes were predicted in the mirDIP database, and 620 lncRNAs targeting miRNAs were predicted in the ENCORI database. The ceRNA regulatory network was constructed using Cytoscape software. Finally, we employed the cMAP database to predict small molecular complexes as potentially effective drugs for the treatment of sepsis, such as chloroquine, harpagoside, and PD-123319. In conclusion, this project successfully identified 7 core genes, which may serve as promising candidates for novel sepsis biomarkers. Meanwhile, we constructed a related ceRNA network and predicted potential targeted drugs, providing potential therapeutic targets and treatment strategies for sepsis patients.

Research Progress on Mechanisms and Treatment of Sepsis-Induced Myocardial Dysfunction

Sepsis is a syndrome of organ dysfunction caused by a dysregulated immune response to infection, with high morbidity and mortality. At present, there have been many advances in the study of its pathogenesis, especially the cardiac dysfunction caused by sepsis, namely sepsis-induced myocardial dysfunction, SIMD, which has received widespread attention. The mechanisms of SIMD mainly include excessive release of inflammatory mediators, impaired mitochondrial function, autophagy, apoptosis and myocardial dysfunction. This article reviews the pathogenesis of SIMD and elaborates on the progress in its treatment, aiming to improve the prognosis of patients with SIMD and sepsis.

Post-Translational Modification of PTEN Protein: Quantity and Activity

Post-translational modifications play crucial roles in regulating protein functions and stabilities. PTEN is a critical tumor suppressor involved in regulating cellular proliferation, survival, and migration processes. However, dysregulation of PTEN is common in various human cancers. PTEN stability and activation/suppression have been extensively studied in the context of tumorigenesis through inhibition of the PI3K/AKT signaling pathway. PTEN undergoes various post-translational modifications, primarily including phosphorylation, acetylation, ubiquitination, SUMOylation, neddylation, and oxidation, which finely tune its activity and stability. Generally, phosphorylation modulates PTEN activity through its lipid phosphatase function, leading to altered power of the signaling pathways. Acetylation influences PTEN protein stability and degradation rate. SUMOylation has been implicated in PTEN localization and interactions with other proteins, affecting its overall function. Neddylation, as a novel modification of PTEN, is a key regulatory mechanism in the loss of tumor suppressor function of PTEN. Although current therapeutic approaches focus primarily on inhibiting PI3 kinase, understanding the post-translational modifications of PTEN could help provide new therapeutic strategies that can restore PTEN's role in PIP3-dependent tumors. The present review summarizes the major recent developments in the regulation of PTEN protein level and activity. We expect that these insights will contribute to better understanding of this critical tumor suppressor and its potential implications for cancer therapy in the future.

Sodium valproate treatment reverses endothelial dysfunction in aorta from rabbits with acute myocardial infarction

Sodium valproate (VPA), a histone deacetylase (HDAC) inhibitor, could be a promising candidate to treat acute myocardial infarction (AMI). In this study, AMI was induced in New Zealand White rabbits by occluding the left circumflex coronary artery for 1 h, followed by reperfusion. The animals were distributed into three experimental groups: the sham-operated group (SHAM), the AMI group and the AMI + VPA group (AMI treated with VPA 500 mg/kg/day). After 5 weeks, abdominal aorta was removed and used for isometric recording of tension in organ baths or protein expression by Western blot, and plasma for the determination of nitrate/nitrite (NOx) levels by colorimetric assay. Our results indicated that AMI induced a reduction of the endothelium-dependent response to acetylcholine without modifying the endothelium-independent response to sodium nitroprusside, leading to endothelial dysfunction. VPA treatment reversed AMI-induced endothelial dysfunction and even increased NO sensitivity in vascular smooth muscle. This response was consistent with an antioxidant effect of VPA, as it was able to reverse the superoxide dismutase 1 (SOD 1) down-regulation induced by AMI. Our experiments also ruled out that the VPA mechanism was related to eNOS, iNOS, sGC and arginase expression or changes in NOx plasma levels. Therefore, we conclude that VPA improves vasodilation by increasing NO bioavailability, likely due to its antioxidant effect. Since endothelial dysfunction was closely related to AMI, VPA treatment could increase aortic blood flow, making it a potential agent in reperfusion therapy that can prevent the vascular damage.

Research Progress on the Preparation and Function of Antioxidant Peptides from Walnuts

Food-derived peptides have good antioxidant activity and are highly safe for humans; consequently, there has been continuous growth in research on antioxidants, with potential applications in food, medicine, cosmetics, and other fields. Among food-derived peptides, walnut-derived peptides have attracted increasing attention as food-derived peptides rich in eight essential amino acids. This review summarizes the progress made in the development and identification of antioxidant peptides in walnut proteins. This article mainly describes the interaction between reactive oxygen species and cellular antioxidant products, modulation of enzyme content and activity, and regulation of the redox signaling pathways and analyzes the mechanisms of reduction in oxidative stress. Finally, the complex structure-activity relationships of walnut-derived peptides are analyzed based on their amino acid composition and secondary structure of the polypeptides. This review provides a theoretical basis for the production of walnut-derived antioxidant peptides and could help promote the development of the walnut industry.

Sweroside functionalized with Mesenchymal Stem cells derived exosomes attenuates sepsis-induced myocardial injury by modulating oxidative stress and apoptosis in rats

Sepsis is a life-threatening problem by organ dysfunction influenced by negative inflammatory responses and stimulated oxidative stress, which most of sepsis patients about 40-60% are accompanied with myocardial injury. Recently, stem cells derived exosomes could effectively apply in the numerous diseases by combined with natural therapeutic agents. In the present investigation, Sweroside functionalized with exosomes to control inflammatory responses by sepsis and significantly proved the function of depreciated myocardial injury-induced by LPS. The sweroside could have effectively delivered to cardiomyocytes cells via exosome carriers. The induced-SMI rats exhibited severe myocardial injury and apoptosis by in vivo experiments and treatment of sweroside-functionalized exosomes (SWO/EX) reassured the phenotypes. Importantly, SWO/EX significantly downregulated the ROS generation in the SMI rat models. The SOD and GSH activity were also suppressed in SMI rat models, and treated models with SWO/EXO could have effective liberating activity in the Rats. Meanwhile, SWO/EXO treated LPS-induced cardiomyocytes displayed that significant reduction of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) levels and also increasing cell survival and prevented apoptosis. Thus, we demonstrate that MS-cells derived exosome with sweroside could have effectively impede sepsis-induced myocardial injury. SWO/EX formulations might be applied as a potent therapeutic agent for SMI therapy.

Apigenin inhibits angiogenesis in retinal microvascular endothelial cells through regulating of the miR-140-5p/HDAC3-mediated PTEN/PI3K/AKT pathway

BACKGROUND

Diabetic retinopathy (DR) is a common cause of visual impairment. Apigenin has been shown to have antiangiogenic effects in various diseases. Our study aimed to investigate the role of apigenin in DR and elucidate the underlying mechanism.

METHODS

Human retinal microvascular endothelial cells (HRMECs) were exposed to high glucose (HG) to establish a DR model. HRMECs were treated with apigenin. Then we knocked down or overexpressed miR-140-5p and HDAC3, and added PI3K/AKT inhibitor LY294002. The expression levels of miR-140-5p, HDAC3, and PTEN were measured using qRT-PCR. Western blot analysis was performed to assess the expression of HDAC3, PTEN, and PI3K/AKT pathway-related proteins. Finally, cell proliferation and migration were evaluated using MTT, wound-healing assay, and transwell assay, while angiogenesis was examined using the tube formation assay.

RESULTS

HG treatment resulted in reduced miR-140-5p expression and overexpression of miR-140-5p suppressed proliferation, migration, and angiogenesis of the HG-induced HRMECs. Apigenin treatment significantly restored the decreased level of miR-140-5p caused by HG treatment and inhibited proliferation, migration, and angiogenesis of the HG-induced HRMECs by upregulating miR-140-5p. Moreover, miR-140-5p targeted HDAC3, and overexpression of miR-140-5p reversed the HG-inducted upregulation of HDAC3 expression. HDAC3 was found to bind to the promoter region of PTEN, inhibiting its expression. Knockdown of HDAC3 suppressed the PI3K/AKT pathway by elevating PTEN expression. Furthermore, apigenin inhibited angiogenesis in DR cell models through the regulating of the miR-140-5p/HDAC3-mediated PTEN/PI3K/AKT pathway.

CONCLUSIONS

Apigenin effectively suppressed angiogenesis in HG-induced HRMECs by modulating the miR-140-5p/HDAC3-mediated PTEN/PI3K/AKT pathway. Our study may contribute to the development of novel therapeutic approaches and identification of potential targets for the treatment of DR.

N-acetylcysteine improves autism-like behavior by recovering autophagic deficiency and decreasing Notch-1/Hes-1 pathway activity

N-acetylcysteine (NAC) has been reported to improve social interaction behavior, irritability, self-injury, and anxiety-like behavior in autism. However, the molecular mechanism underlying the therapeutic roles of NAC in autism remains unknown. This study mainly aimed to investigate the therapeutic effect of NAC on valproic acid (VPA)-induced autism model and the underlying mechanisms. Our results showed that NAC ameliorated the deficits in sociability and the anxiety- and repetitive-like behaviors displayed by VPA-exposed rats. In addition, VPA exposure induced autophagic deficiency and enhanced Notch-1/Hes-1 pathway activity based on lowered Beclin-1 and LC3B levels, while increased expression of p62, Notch-1, and Hes-1 expression at the protein level. However, NAC recovered VPA-induced autophagic deficiency and reduced Notch-1/Hes-1 pathway activity in a VPA-exposed autism rat model and SH-SY5Y neural cells. The present results demonstrated that NAC improves autism-like behavioral abnormalities by inactivating Notch-1/Hes-1 signaling pathway and recovering autophagic deficiency. Taken together, this study helps to elucidate a novel molecular mechanism that underlies the therapeutic actions of NAC in autism and suggests its potential to ameliorate behavioral abnormalities in neurodevelopmental disorders.

The role of histone deacetylases in cardiac energy metabolism in heart diseases

Heart diseases are associated with substantial morbidity and mortality worldwide. The underlying mechanisms and pathological changes associated with cardiac diseases are exceptionally complex. Highly active cardiomyocytes require sufficient energy metabolism to maintain their function. Under physiological conditions, the choice of fuel is a delicate process that depends on the whole body and organs to support the normal function of heart tissues. However, disordered cardiac metabolism has been discovered to play a key role in many forms of heart diseases, including ischemic heart disease, cardiac hypertrophy, heart failure, and cardiac injury induced by diabetes or sepsis. Regulation of cardiac metabolism has recently emerged as a novel approach to treat heart diseases. However, little is known about cardiac energy metabolic regulators. Histone deacetylases (HDACs), a class of epigenetic regulatory enzymes, are involved in the pathogenesis of heart diseases, as reported in previous studies. Notably, the effects of HDACs on cardiac energy metabolism are gradually being explored. Our knowledge in this respect would facilitate the development of novel therapeutic strategies for heart diseases. The present review is based on the synthesis of our current knowledge concerning the role of HDAC regulation in cardiac energy metabolism in heart diseases. In addition, the role of HDACs in different models is discussed through the examples of myocardial ischemia, ischemia/reperfusion, cardiac hypertrophy, heart failure, diabetic cardiomyopathy, and diabetes- or sepsis-induced cardiac injury. Finally, we discuss the application of HDAC inhibitors in heart diseases and further prospects, thus providing insights into new treatment possibilities for different heart diseases.

Parecoxib attenuates inflammation injury in septic H9c2 cells by regulating the MAPK signaling pathway

Parecoxib, a non-steroidal anti-inflammatory drug, has been reported to possess protective effects against sepsis. However, its detailed role and underlying mechanisms in septic cardiomyopathy remain unclear. Therefore, the goal of the present study was to clarify the function and to investigate the mechanisms of parecoxib in lipopolysaccharide (LPS)-treated H9c2 rat cardiomyocytes. TNF-α, IL-1β and IL-6 expression levels in parecoxib-treated H9c2 cells stimulated with LPS were assessed using ELISA. Parecoxib-treated H9c2 cells stimulated with LPS were tested for viability using the Cell Counting Kit-8 assay. Western blotting analysis and 5-ethynyl-2'-deoxyuridine were used to evaluate cell proliferation. Apoptosis was assessed using TUNEL and western blotting. To assess the protein expression of the MAPK signaling pathway, western blotting was performed. The data showed that parecoxib significantly and dose-dependently reduced the inflammatory responses of LPS-treated H9c2 cells. Parecoxib also significantly and dose-dependently increased the proliferation and inhibited the apoptosis of LPS-treated H9c2 cells. In addition, parecoxib significantly suppressed the activation of the MAPK (p38, JNK and ERK) signaling pathway. The current study indicated that parecoxib could be a viable therapeutic option for septic cardiomyopathy.

Protective effect of HDACIs in improves survival and organ injury after CLP-induced sepsis

Introduction

The effects of isoform-specific histone deacetylase inhibitors (HDACIs) and the non-selective HDACI on sepsis have been profoundly reported. However, the best HDAC classes have not been fully evaluated. Therefore, this study aimed to determine which HDACIs are responsible for survival and beneficial for organ injury.

Methods

Experiment I, SD rats were subjected to cecal ligation and puncture and randomly assigned to the no treatment, dimethyl sulfoxide (DMSO) only, MS-275, LMK-235, tubastatinA (TubA), trichostatin-A (TSA), and sirtinol groups (n = 5). Survival was monitored for 48 h. Experiment II, the animals were monitored for 12 h, then, blood and tissues sample were collected. Interleukin (IL)-6, IL-1β, tumour necrosis factor (TNF)-α, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase (CK) and lactate dehydrogenase (LDH) expressions were evaluated using ELISA. Liver, heart and lung tissues were analysed via hematoxylin and eosin staining. Liver and heart tissue lysates were analysed for acetylated histones H3, H4, a-tubulin and nuclear factor kappa B (NF-κB), IL-6, IL-1β, and TNF-α using western blotting. Splenocytes were examined via flow cytometry to analyse the immune cell population.

Results

MS-275, TubA and TSA treatments significantly prolonged survival. MS-275, LMK-235, TubA and TSA significantly reduced the histopathological scores and AST, ALT, CK, LDH, IL-6, IL-1β and TNF-α levels, significantly increased acetylated of NF-κB and changed the immune cell proportion.

Conclusion

Our results indicated that HDACI classes I and IIb and non-selective HDACI can significantly prolong survival. Moreover, non-selective and isoform-specific class I and IIa/IIb HDACIs can attenuate inflammation and organ injury.

Epigenetic mechanisms of Immune remodeling in sepsis: targeting histone modification

Sepsis is a life-threatening disorder disease defined as infection-induced dysregulated immune responses and multiple organ dysfunction. The imbalance between hyperinflammation and immunosuppression is a crucial feature of sepsis immunity. Epigenetic modifications, including histone modifications, DNA methylation, chromatin remodeling, and non-coding RNA, play essential roles in regulating sepsis immunity through epi-information independent of the DNA sequence. In recent years, the mechanisms of histone modification in sepsis have received increasing attention, with ongoing discoveries of novel types of histone modifications. Due to the capacity for prolonged effects on immune cells, histone modifications can induce immune cell reprogramming and participate in the long-term immunosuppressed state of sepsis. Herein, we systematically review current mechanisms of histone modifications involved in the regulation of sepsis, summarize their role in sepsis from an immune perspective and provide potential therapeutic opportunities targeting histone modifications in sepsis treatment.

A comprehensive review on pharmacological applications and drug-induced toxicity of valproic acid

Valproic acid, a branching short chain fatty acid, is a popular drug to treat epilepsy and acts as a mood-stabilizing drug. The obstruction of ion channels and Gamma Amino Butyrate transamino butyrate GABA has been linked to antiepileptic effects. Valproic acid has been characterized as a Histone deacetylase inhibitor, functioning directly transcription of gene levels by blocking the deacetylation of histones and increasing the accessibility of transcription sites. Study has been extensively focused on pharmaceutical activity of valproic acid through various pharmacodynamics activity from absorption, distribution and excretion particularly in patients who are resistant to or intolerant of lithium or carbamazepine, as well as those with mixed mania or rapid cycling.

Epigenetic and post-translational modifications in autophagy: biological functions and therapeutic targets

Autophagy is a conserved lysosomal degradation pathway where cellular components are dynamically degraded and re-processed to maintain physical homeostasis. However, the physiological effect of autophagy appears to be multifaced. On the one hand, autophagy functions as a cytoprotective mechanism, protecting against multiple diseases, especially tumor, cardiovascular disorders, and neurodegenerative and infectious disease. Conversely, autophagy may also play a detrimental role via pro-survival effects on cancer cells or cell-killing effects on normal body cells. During disorder onset and progression, the expression levels of autophagy-related regulators and proteins encoded by autophagy-related genes (ATGs) are abnormally regulated, giving rise to imbalanced autophagy flux. However, the detailed mechanisms and molecular events of this process are quite complex. Epigenetic, including DNA methylation, histone modifications and miRNAs, and post-translational modifications, including ubiquitination, phosphorylation and acetylation, precisely manipulate gene expression and protein function, and are strongly correlated with the occurrence and development of multiple diseases. There is substantial evidence that autophagy-relevant regulators and machineries are subjected to epigenetic and post-translational modulation, resulting in alterations in autophagy levels, which subsequently induces disease or affects the therapeutic effectiveness to agents. In this review, we focus on the regulatory mechanisms mediated by epigenetic and post-translational modifications in disease-related autophagy to unveil potential therapeutic targets. In addition, the effect of autophagy on the therapeutic effectiveness of epigenetic drugs or drugs targeting post-translational modification have also been discussed, providing insights into the combination with autophagy activators or inhibitors in the treatment of clinical diseases.

Shenxian-Shengmai Oral Liquid Evoke Autophagy of Fibroblast to Attenuate Sinoatrial Node Fibrosis in Sick Sinus Syndrome Mice via the AKT/mTOR Pathway

Sick sinus syndrome (SSS) is closely associated with cardiac syncope and sudden death, wherein sinoatrial node (SAN) fibrosis is one of the main pathological changes that occur. Shenxian-Shengmai oral liquid (SXSM) has been clinically proven to significantly improve the heart rate of SSS patients. In this study, we aimed to explore the mechanism of SXSM in reducing the SAN fibrosis by combining in vitro and in vivo experiments. Accordingly, the SSS model was constructed by slowly pumping angiotensin II (AngII) with a micro-osmotic pump. The degree of fibrosis was evaluated by Masson's trichrome staining and immunofluorescence staining of the fibrosis marker protein. In addition, NIH-3T3 mouse fibroblasts were used to simulate SAN fibroblasts to further explore the mechanism, with AngII used as the cellular fibrosis inducer. Monodansylcadaverine (MDC) staining and transmission electron microscopy were employed to assay the autophagy content, whereas immunofluorescence staining and Western blotting were employed to elucidate the related protein expression. Finally, fibroblasts were given the AKT phosphorylation agonist SC79 to reversely verify the effects of SXSM. The results showed that SXSM could significantly increase the heart rate of SSS mice by reducing the deposition of extracellular matrix (ECM) in SAN induced by AngII. According to in vivo experiments, when compared with the model group, SSS mice treated with SXSM developed less fibrosis in the SAN area. In vitro experiments revealed that AngII could restrain autophagy by activating the phosphorylation of the AKT/mTOR pathway, thereby increasing the deposition of ECM. Moreover, SXSM pretreatment prevented this upregulation. After the intervention of SC79, the protective effect of SXSM was weakened. In conclusion, SXSM activated autophagy through the AKT/mTOR pathway, which in turn reduced the deposition of the ECM in SAN induced by AngII, attenuated the fibrosis of SAN, and improved the decreased heart rate in the SSS mice.

The cardioprotective effects of perindopril in a model of polymicrobial sepsis: The role of radical oxygen species and the inflammation pathway

Mortality rates associated with myocardial dysfunction due to sepsis and septic shock are generally high across the world. The present study focused on the antioxidant and anti-inflammatory effects of perindopril (PER) for the purpose of preventing the adverse effects of sepsis on the myocardium and developing new alternatives in treatment. The control group received only saline solution via the oral route for 4 days. The second group underwent cecal ligation puncture (CLP), and the third underwent CLP and received PER (2 mg/kg). Rats in the third group received 2 mg/kg PER per oral (p.o.) from 4 days before induction of sepsis. Thiobarbituric acid reactive species (TBARS), total thiol (-SH), interleukin-1 beta (IL-1β), IL-6, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and nuclear factor kappa B (NF-κB/p65) levels increased in the CLP groups. In contrast, PER (2 mg/kg) decreased the levels of biochemical parameters other than total-SH and decreased 8-OHdG, NF-κB/p65 immunopositivity in rat heart tissues. The data from this study show that impairment of the oxidant/antioxidant balance and inflammatory cytokine levels in favor of inflammation in heart tissue under septic conditions results in severe tissue damage. PER administration before sepsis was shown to exhibit antioxidant and anti-inflammatory properties by reducing these effects. This in turn increased the importance of PER as new evidence of its protective effects in heart tissue.

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.

Role of Age-Related Changes in DNA Methylation in the Disproportionate Susceptibility and Worse Outcomes of Sepsis in Older Adults

Sepsis, a complex multisystem disorder, is among the top causes of hospitalization and mortality in older adults. However, the mechanisms underlying the disproportionate susceptibility to sepsis and worse outcomes in the elderly are not well understood. Recently, changes in DNA methylation have been shown to be linked to aging processes and age-related diseases. Thus, we postulated that age-related changes in DNA methylation may play a role in the onset and prognosis of sepsis in elderly patients. Here, we performed genome-wide methylation profiling of peripheral blood from patients with sepsis and controls. Among the CpG sites whose methylation changes may contribute to an increase in sepsis susceptibility or mortality, 241 sites that possessed age-related changes in DNA methylation in controls may partly explain the increased risk of sepsis in older adults, and 161 sites whose methylation significantly correlated with age in sepsis group may be the potential mechanisms underlying the worse outcomes of elderly septic patients. Finally, an independent cohort was used to validate our findings. Together, our study demonstrates that age-related changes in DNA methylation may explain in part the disproportionate susceptibility and worse outcomes of sepsis in older adults.

Mammalian AKT, the Emerging Roles on Mitochondrial Function in Diseases

Mitochondrial dysfunction may play a crucial role in various diseases due to its roles in the regulation of energy production and cellular metabolism. Serine/threonine kinase (AKT) is a highly recognized antioxidant, immunomodulatory, anti-proliferation, and endocrine modulatory molecule. Interestingly, increasing studies have revealed that AKT can modulate mitochondria-mediated apoptosis, redox states, dynamic balance, autophagy, and metabolism. AKT thus plays multifaceted roles in mitochondrial function and is involved in the modulation of mitochondria-related diseases. This paper reviews the protective effects of AKT and its potential mechanisms of action in relation to mitochondrial function in various diseases.

The evolution of knowledge on genes associated with human diseases

Thousands of biomedical scientific articles, including those describing genes associated with human diseases, are published every week. Computational methods such as text mining and machine learning algorithms are now able to automatically detect these associations. In this study, we used a cognitive computing text-mining application to construct a knowledge network comprising 3,723 genes and 99 diseases. We then tracked the yearly changes on these networks to analyze how our knowledge has evolved in the past 30 years. Our systems approach helped to unravel the molecular bases of diseases and detect shared mechanisms between clinically distinct diseases. It also revealed that multi-purpose therapeutic drugs target genes that are commonly associated with several psychiatric, inflammatory, or infectious disorders. By navigating this knowledge tsunami, we were able to extract relevant biological information and insights about human diseases.

Hidden pharmacological activities of valproic acid: A new insight

Valproic acid (VPA) is an approved drug for managing epileptic seizures, bipolar disorders, and migraine. VPA has been shown to elevate the level of gamma-aminobutyric acid (GABA) in the brain through competitive inhibition of GABA transaminase, thus promoting the availability of synaptic GABA and facilitating GABA-mediated responses. VPA, which is a small chain of fatty acids, prevents histone deacetylases (HDACs). HDACs play a crucial role in chromatin remodeling and gene expression through posttranslational changes of chromatin-associated histones. Recent studies reported a possible effect of VPA against particular types of cancers. This effect was partially attributed to its role in regulating epigenetic modifications through the inhibition of HDACs, which affect the expression of genes associated with cell cycle control, cellular differentiation, and apoptosis. In this review, we summarize the current information on the actions of VPA in diseases such as diabetes mellitus, kidney disorders, neurodegenerative diseases, muscular dystrophy, and cardiovascular disorders.

Bone marrow-mesenchymal stem cell-derived exosomal microRNA-141 targets PTEN and activates β-catenin to alleviate myocardial injury in septic mice

BACKGROUND

Mesenchymal stem cells (MSCs) and their derived exosomes have shown potentials in the control of myocardial dysfunction. This study aimed to reveal the function of bone marrow (BM)-MSC-derived exosomes in sepsis-induced myocardial injury and the molecular mechanism.

METHODS

BM-MSC-derived exosomes were obtained and identified. A mouse model with sepsis was induced by cecalligation puncture (CLP) and treated with exosomes. The myocardial function of mice, the production of creatine kinase MB (CK-MB) and lactate dehydrogenase (LDH) in serum, the phosphorylation of a key myocardial contractility-related protein phospholamban (PLB), and the pathological changes in the myocardial tissues were examined. A microRNA (miRNA) microarray analysis was performed to examine the candidate miRNAs carried by the exosomes. Rescue experiments were conducted to validate the involvement of miR-141.

RESULTS

CLP treatment led to sepsis and notably reduced the myocardial function in mice. Further treatment of BM-MSC-derived exosomes alleviated the CLP-induced myocardial impairment, production of CK-MB and LDH, and inflammatory infiltration and cell apoptosis in mouse myocardial tissues, and restored the PLB phosphorylation. miR-141 was the most upregulated miRNA in the myocardial tissues after exosome treatment. Downregulation of miR-141 blocked the myocardium-protective functions of the exosomes. miR-141 was found to bind to and suppress PTEN expression, which further enhanced the activity of β-catenin.

CONCLUSION

This study suggested that BM-MSC derived exosomes ameliorates myocardial injury in septic mice through conveying miRNA-141 and regulating the PTEN/β-catenin axis, and exosomes may serve as promising tools for the management of myocardial injury induced by sepsis or other factors.

The critical roles of histone deacetylase 3 in the pathogenesis of solid organ injury

Histone deacetylase 3 (HDAC3) plays a crucial role in chromatin remodeling, which, in turn, regulates gene transcription. Hence, HDAC3 has been implicated in various diseases, including ischemic injury, fibrosis, neurodegeneration, infections, and inflammatory conditions. In addition, HDAC3 plays vital roles under physiological conditions by regulating circadian rhythms, metabolism, and development. In this review, we summarize the current knowledge of the physiological functions of HDAC3 and its role in organ injury. We also discuss the therapeutic value of HDAC3 in various diseases.

Pathogenetic mechanisms of septic cardiomyopathy

Sepsis is a serious complication after infection, whose further development may lead to multiple organ dysfunction syndrome and so on. It is an important cause of death in critically ill patients who suffered an infection. Sepsis cardiomyopathy is a common complication that exacerbates the prognosis of patients. At present, though the pathogenesis of sepsis cardiomyopathy is not completely clear, in-depth study of the pathogenesis of sepsis cardiomyopathy and the discovery of its potential therapeutic targets may decrease the mortality of sepsis patients and bring clinical benefits. This article reviews mitochondrial dysfunction, mitophagy, oxidation stress, and other mechanisms in sepsis cardiomyopathy.

Inhibiting miR-205 Alleviates Cardiac Ischemia/Reperfusion Injury by Regulating Oxidative Stress, Mitochondrial Function, and Apoptosis

BACKGROUND

miR-205 is important for oxidative stress, mitochondrial dysfunction, and apoptosis. The roles of miR-205 in cardiac ischemia/reperfusion (I/R) injury remain unknown. The aim of this research is to reveal whether miR-205 could regulate cardiac I/R injury by focusing upon the oxidative stress, mitochondrial function, and apoptosis.

METHODS

Levels of miR-205 and Rnd3 were examined in the hearts with I/R injury. Myocardial infarct size, cardiac function, oxidative stress, mitochondria function, and cardiomyocyte apoptosis were detected in mice with myocardial ischemia/reperfusion (MI/R) injury. The primary neonatal cardiomyocytes underwent hypoxia/reoxygenation (H/R) to simulate MI/R injury.

RESULTS

miR-205 levels were significantly elevated in cardiac tissues from I/R in comparison with those from Sham. In comparison with controls, levels of Rnd3 were significantly decreased in the hearts from mice with MI/R injury. Furthermore, inhibiting miR-205 alleviated MI/R-induced apoptosis, reduced infarct size, prevented oxidative stress increase and mitochondrial fragmentation, and improved mitochondrial functional capacity and cardiac function. Consistently, overexpression of miR-205 increased infarct size and promoted apoptosis, oxidative stress, and mitochondrial dysfunction in mice with MI/R injury. In cultured mouse neonatal cardiomyocytes, downregulation of miR-205 reduced oxidative stress in H/R-treated cardiomyocytes. Finally, inhibiting Rnd3 ablated the cardioprotective effects of miR-205 inhibitor in MI/R injury.

CONCLUSIONS

We conclude that inhibiting miR-205 reduces infarct size, improves cardiac function, and suppresses oxidative stress, mitochondrial dysfunction, and apoptosis by promoting Rnd3 in MI/R injury. miR-205 inhibitor-induced Rnd3 activation is a valid target to treat MI/R injury.

Modulation of cathelicidin and defensins by histone deacetylase inhibitors: A potential treatment for multi-drug resistant infectious diseases

Infectious diseases are an important growing public health problem, which perspective has worsened due to the increasing number of drug-resistant strains in the last few years. Although diverse solutions have been proposed, one viable solution could be the use of immune system modulators. The induction of the immune response can be increased by histone deacetylase inhibitors (iHDAC), which in turn modulate the chromatin and increase the activation of different cellular pathways and nuclear factors such as STAT3, HIF-1α NF-kB, C/EBPα and, AP-1. These pathways are capable to promote several immune response-related molecules including those with antimicrobial properties such as antimicrobial peptides (AMPs) that lead to the elimination of pathogens including multi drug-resistant strains.

Polydatin Alleviates Septic Myocardial Injury by Promoting SIRT6-Mediated Autophagy

Sepsis is a life-threatening condition. Polydatin (PD), a small natural compound from Polygonum cuspidatum, possesses antioxidant and anti-inflammatory properties. However, the protective mechanism of PD on sepsis-induced acute myocardial damage is still unclear. The aim of this study was to investigate the effect and mechanism of action of PD on lipopolysaccharide (LPS)-induced H9c2 cells and in a rat model of sepsis, and explored the role of PD-upregulated sirtuin (SIRT)6. LPS-induced H9c2 cells were used to simulate sepsis. Cecal ligation and puncture (CLP)-induced sepsis in rats were used to verify the protective effect of PD. ELISA, western blotting, immunofluorescence, immunohistochemistry, and flow cytometry were used to study the protective mechanism of PD against septic myocardial injury. PD pretreatment suppressed LPS-induced H9c2 cell apoptosis by promotion of SIRT6-mediated autophagy. Downregulation of SIRT6 or inhibition of autophagy reversed the protective effect of PD on LPS-induced apoptosis. PD pretreatment also suppressed LPS-induced inflammatory factor expression. CLP-induced sepsis in rats showed that PD pretreatment decreased CLP-induced myocardial apoptosis and serum tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 expression. 3-Methyladenine (autophagy inhibitor) pretreatment prevented the protective effect of PD on septic cardiomyopathy. SIRT6 expression was increased with PD treatment, which confirmed that PD attenuates septic cardiomyopathy by promotion of SIRT6-mediated autophagy. All these results indicate that PD has potential therapeutic effects that alleviate septic myocardial injury by promotion of SIRT6-mediated autophagy.

Inhibiting miR-22 Alleviates Cardiac Dysfunction by Regulating Sirt1 in Septic Cardiomyopathy

High morbidity and mortality are the most typical characteristics of septic cardiomyopathy. We aimed to reveal the role of miR-22 in septic cardiomyopathy and to explore the underlying mechanisms. miR-22 cardiac-specific knockout (miR-22^cKO) mice and miR-22 cardiac-specific transgenic (miR-22^cOE) mice were subjected to a cecal ligation and puncture (CLP) operation, while a sham operation was used in the control group. The echocardiogram results suggested that miR-22^cKO CLP mice cardiac dysfunction was alleviated. The serum LDH and CK-MB were reduced in the miR-22^cKO CLP mice. As expected, there was reduced apoptosis, increased autophagy and alleviated mitochondrial dysfunction in the miR-22^cKO CLP mice, while it had contrary role in the miR-22^cOE group. Inhibiting miR-22 promoted autophagy by increasing the LC3II/GAPDH ratio and decreasing the p62 level. Additionally, culturing primary cardiomyocytes with lipopolysaccharide (LPS) simulated sepsis-induced cardiomyopathy in vitro. Inhibiting miR-22 promoted autophagic flux confirmed by an increased LC3II/GAPDH ratio and reduced p62 protein level under bafilomycin A1 conditions. Knocking out miR-22 may exert a cardioprotective effect on sepsis by increasing autophagy and decreasing apoptosis via sirt1. Our results revealed that targeting miR-22 may become a new strategy for septic cardiomyopathy treatment.

Spatiotemporal evaluation of the mouse embryonic redox environment and histiotrophic nutrition following treatment with valproic acid and 1,2-dithiole-3-thione during early organogenesis

Redox regulation during metazoan development ensures that coordinated metabolic reprogramming and developmental signaling are orchestrated with high fidelity in the hypoxic embryonic environment. Valproic acid (VPA), an anti-seizure medication, is known to increase markers of oxidation and also increase the risk of neural tube defects (NTDs) when taken during pregnancy. It is unknown, however, whether oxidation plays a direct role in failed neural tube closure (NTC). Spatial and temporal fluctuations in total glutathione (GSH) and total cysteine (Cys) redox steady states were seen during a 24 h period of CD-1 mouse organogenesis in untreated conceptuses and following exposure to VPA and the Nrf2 antioxidant pathway inducer, 1,2-dithiole-3-thione (D3T). Glutathione, glutathione disulfide (GSSG), and Cys, cystine (CySS) concentrations, measured in conceptal tissues (embryo/visceral yolk sac) and fluids (yolk sac fluid/amniotic fluid) showed that VPA did not cause extensive and prolonged oxidation during the period of NTC, but instead produced transient periods of oxidation, as assessed by GSH:GSSG redox potentials, which revealed oxidation in all four conceptal compartments at 4, 10, and 14 h, corresponding to the period of heartbeat activation and NTC. Other changes were tissue and time specific. VPA treatment also reduced total FITC-Ab clearance from the medium over 3 h, indicating potential disruption of nutritive amino acid supply. Overall, these results indicated that VPA's ability to affect cellular redox status may be limited to tissue-specific windows of sensitivity during the period of NTC. The safety evaluation of drugs used during pregnancy should consider time and tissue specific redox factors.

MiR-22-3p suppresses sepsis-induced acute kidney injury by targeting PTEN

Background: Septic acute kidney injury is considered as a severe and frequent complication that occurs during sepsis. The present study was performed to understand the role of miR-22-3p and its underlying mechanism in sepsis-induced acute kidney injury.

Methods: Rats were injected with adenovirus carrying miR-22-3p or miR-NC in the caudal vein before cecal ligation. Meanwhile, HK-2 cells were transfected with the above adenovirus following LPS stimulation. We measured the markers of renal injury (blood urea nitrogen (BUN), serum creatinine (SCR)). Histological changes in kidney tissues were examined by hematoxylin and eosin (H&E), Masson staining, periodic acid Schiff staining and TUNEL staining. The levels of IL-1β, IL-6, TNF-α and NO were determined by ELISA assay. Using TargetScan prediction and luciferase reporter assay, we predicted and validated the association between PTEN and miR-22-3p.

Results: Our data showed that miR-22-3p was significantly down-regulated in a rat model of sepsis-induced acute kidney injury, in vivo and LPS-induced sepsis model in HK-2 cells, in vitro. Overexpression of miR-22-3p remarkably suppressed the inflammatory response and apoptosis via down-regulating HMGB1, p-p65, TLR4 and pro-inflammatory factors (IL-1β, IL-6, TNF-α and NO), both in vivo and in vitro. Moreover, PTEN was identified as a target of miR-22-3p. Furthermore, PTEN knockdown augmented, while overexpression reversed the suppressive role of miR-22-3p in LPS-induced inflammatory response.

Conclusions: Our results showed that miR-22-3p induced protective role in sepsis-induced acute kidney injury may rely on the repression of PTEN.

Exosomes with high level of miR-181c from bone marrow-derived mesenchymal stem cells inhibit inflammation and apoptosis to alleviate spinal cord injury

Stem cell transplantation is a promising method in the treatment of spinal cord injury (SCI). Researches have shown that stem cell-derived exosomes as well as its contents such as microRNAs contribute to the protective effects of stem cell against SCI. However, the effects of exosomes derived from bone marrow stem cells on SCI and the underlying mechanisms remain unknown. In this study, we collected bone marrow stem cells derived exosomes (BMSCs-exo) to deal with SCI rats and LPS induced microglia to explore the possible mechanisms. We found that BMSCs-exo showed significant effects on decreasing pro-inflammatory cytokines as well as increasing Basso-Beattie-Bresnahan score after acute SCI. MicroRNA-181c levels in tissue were elevated with the use of BMSCs-exo. Then we verified the effect in vitro and found that in LPS induced microglia, the administration of BMSCs-exo could inhibit the expression of pro-inflammatory cytokines, and the phosphorylation of NF-κB signal was also suppressed. During which, the expression of microRNA-181c in microglia was elevated. When LPS induced microglia were treated with BMSCs-exo over-expressing microRNA-181c, the levels of pro-inflammatory cytokines decreased. Then bioinformatics techniques were used to detect the possible target gene of microRNA-181c and then PTEN was found as a candidate. Further experiments showed that the protection effects of BMSCs-exo over-expressing microRNA-181c could be antagonized by the elevation of PTEN expression both in vitro and in vivo. In conclusion, we verified that BMSCs-exo could protect against SCI through its content microRNA-181c which suppressed the inflammation in microglia and spinal cord. It was related to the inhibition of PTEN and the suppression of NF-κB signal, and finally decreasing inflammation and apoptosis in spinal cord and improved SCI.

Inhibition of PTEN Ameliorates Secondary Hippocampal Injury and Cognitive Deficits after Intracerebral Hemorrhage: Involvement of AKT/FoxO3a/ATG-Mediated Autophagy

Spontaneous intracerebral hemorrhage (ICH) commonly causes secondary hippocampal damage and delayed cognitive impairments, but the mechanisms remain elusive. Here, we sought to identify the molecular mechanisms underlying these hemorrhagic outcomes in a rat autologous blood model of ICH. First, a significant increase in phosphatase and tensin homolog (PTEN) expression was observed in nonhemorrhagic ipsilateral hippocampus. However, systemic administration of PTEN inhibitor BPV or hippocampal injection of PTEN siRNA could prevent hippocampal neuronal injury and cognitive dysfunctions after ICH. Furthermore, we also found that ICH robustly triggered autophagic neuronal death in the ipsilateral hippocampus, but which were strongly reduced by PTEN knockdown. Notably, suppression of autophagy effectively attenuated poststroke hippocampal inflammation, neuronal damage, and cognitive decline, suggesting the beneficial effects of PTEN deletion was associated with autophagy inactivation. Specifically, PTEN antagonized the PI3K/AKT signaling and downstream effector FoxO3a phosphorylation and subsequently enhanced nuclear translocation of FoxO3a to drive proautophagy gene program, but these changes were diminished upon PTEN inhibition. More importantly, lentivirus-mediated FoxO3a overexpression apparently abrogated the antiauotphagy effect of PTEN deletion via enhancing autophagy-related gene (ATG) transcription. Collectively, these results suggest that knockdown of PTEN alleviated progressive hippocampal injury and cognitive deficits by suppression of autophagy induction involving the AKT/FoxO3a/ATG axis after ICH. Thus, this study provides a novel and promising therapeutic target for the treatment of hemorrhagic stroke.

Xanthohumol attenuates isoprenaline-induced cardiac hypertrophy and fibrosis through regulating PTEN/AKT/mTOR pathway

Emerging evidence suggests the cardiovascular protective effects of Xanthohumol (Xn), a prenylated flavonoid isolated from the hops (Humulus lupulus L.). However, the cardioprotective effect of Xn remains unclear. Present study aimed to investigate the protective role of Xn against isoprenaline (ISO)-induced cardiac hypertrophy and fibrosis, and elucidate the underlying mechanism. The cardiac hypertrophy and fibrosis model were established via subcutaneously administration of ISO. ISO reduced the left ventricular contractile function and elevated myocardial enzyme levels, suggesting cardiac dysfunction. Moreover, the increased cardiac myocyte area, heart weight/body weight (HW/BW) ratio and ANP/BNP expressions indicated the ISO-induced hypertrophy, while the excessive collagen-deposition and up-regulation of fibrosis marker protein (α-SMA, Collagen-I/III) expression indicated the ISO-induced fibrosis. The ISO-induced cardiac dysfunction, hypertrophy and fibrosis were significantly attenuated by oral administrated with Xn. PTEN/AKT/mTOR pathway has been reported to involve in pathogenesis of cardiac hypertrophy and fibrosis. We found that Xn administration up-regulated PTEN expression and inhibited the phosphorylation of AKT/mTOR in ISO-treated mice. Moreover, treating with VO-ohpic, a specific PTEN inhibitor, abolished the cardioprotective effect of Xn. Collectively, these results suggested that Xn attenuated ISO-induced cardiac hypertrophy and fibrosis through regulating PTEN/AKT/mTOR pathway.

Xanthohumol Inhibits TGF-β1-Induced Cardiac Fibroblasts Activation via Mediating PTEN/Akt/mTOR Signaling Pathway

Background

Xanthohumol (Xn) is the most abundant prenylated flavonoid in Hops (Humulus lupulus L.), and exhibits a range of pharmacological activities. This study aimed to investigate the effect of Xn on TGF-β1-induced cardiac fibroblasts activation and elucidate the underlying mechanism.

Materials and Methods

The cellTiter 96^® AQueous one solution cell proliferation assay kit was adopted to determine the cell viability of cardiac fibroblasts, and the proliferation was detected through 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay. The α-SMA protein expression was measured by using immunofluorescence and Western blotting. Western blotting was conducted to test the protein expressions of collagen I and III, PTEN, p-Akt, Akt, p-mTOR, mTOR, p-Smad3, Smad3 and GAPDH. The mRNA levels of α-SMA, collagen I and III were determined by quantitative real-time polymerase chain reaction (PCR).

Results

Xn inhibited the TGF-β1-induced proliferation, differentiation and collagen overproduction of cardiac fibroblasts. TGF-β1 induced the down-regulated PTEN expression, Akt and mTOR phosphorylation. These effects of TGF-β1 were suppressed by Xn, while blocking of PTEN reduced Xn-mediated inhibitory effect on cardiac fibroblasts activation induced by TGF-β1.

Conclusion

Xn inhibits TGF-β1-induced cardiac fibroblasts activation via mediating PTEN/Akt/mTOR signaling pathway.

Biocompatible sulfated valproic acid-coupled polysaccharide-based nanocarriers with HDAC inhibitory activity

The development of bio-based nanoparticles (NPs) as drug containers is of increasing interest to circumvent several obstacles in drug therapy such as rapid drug metabolization, short serum half-life, and unspecific side effects. The histone deacetylase inhibitor valproic acid (VPA) is known for its anti-inflammatory as well as for its anti-cancer activity. Here, recently developed VPA-loaded NPs based on cellulose- and dextran VPA esters were modified with sulfuric acid half ester moieties to improve intracellular drug release. The NPs show rapid cellular uptake, are non-toxic in vitro and in vivo, and able to induce histone H3 hyperacetylation. Thus, they represent a potent drug delivery system for the application in a variety of treatment settings, such as inflammation, sepsis and defined cancer types. In addition, the flexible NP-system offers a broad range of further options for modification, e.g. for targeting strategies and multi-drug approaches.

miR-214-3p Attenuates Sepsis-Induced Myocardial Dysfunction in Mice by Inhibiting Autophagy through PTEN/AKT/mTOR Pathway

Aims. More than half of the patients with sepsis would develop cardiac dysfunction, which is termed as sepsis-induced myocardial dysfunction (SIMD). Previous studies suggest that autophagy may play an important role in SIMD. The present study investigated whether miR-214-3p could attenuate SIMD by inhibiting autophagy. Main Methods. In this article, we investigated the role of autophagy in a mouse model of cecal ligation and puncture (CLP). The structure and function of hearts harvested from the mice were evaluated. Myocardial autophagy levels were detected with immunohistochemical, immunofluorescent, and Western blot. Key Findings. miR-214-3p can alleviate SIMD in septic mice by inhibiting the level of cardiac autophagy to attenuate myocardial dysfunction. Moreover, this study showed that miR-214-3p inhibited autophagy by silencing PTEN expression in the myocardial tissues of septic mice. Significance. This study showed that miR-214-3p attenuated SIMD through myocardial autophagy inhibition by silencing PTEN expression and activating the AKT/mTOR pathway. The present findings supported that miR-214-3p may be a potential therapeutic target for SIMD.

Melatonin ameliorates pressure overload-induced cardiac hypertrophy by attenuating Atg5-dependent autophagy and activating the Akt/mTOR pathway

Cardiac hypertrophy, including hypertension and valvular dysfunction, is a pathological feature of many cardiac diseases that ultimately leads to heart failure. Melatonin confers a protective role against pathological cardiac hypertrophy, but the underlying mechanisms remain elusive. In the present study, we hypothesized that melatonin protects against pressure overload-induced cardiac hypertrophy by attenuating Atg5-dependent autophagy and activating the Akt/mTOR pathway. Male C57BL/6 mice that received adenovirus carrying cardiac-specific Atg5 (under the cTNT promoter; Ad-cTNT-Atg5) underwent transverse aortic constriction (TAC) or sham operation and received an intraperitoneal injection of melatonin (10 mg/kg/d), vehicle or LY294002 (10 mg/kg/d) for 8 weeks. Melatonin treatment for 8 weeks markedly attenuated cardiac hypertrophy and restored impaired cardiac function, as indicated by a decreased HW/BW ratio, reduced cell cross-sectional area and fibrosis, downregulated the mRNA levels of ANP, BNP, and β-MHC and ameliorated adverse effects on the LVEF and LVFS. Melatonin treatment also inhibited apoptosis and alleviated autophagy dysfunction. Furthermore, melatonin inhibited Akt/mTOR pathway activation, while these effects were blocked by LY294002. In addition, the effect of melatonin regulation on TAC-induced autophagy dysfunction was inhibited by LY294002 or cardiac-specific Atg5 overexpression. As expected, Akt/mTOR pathway inhibition or cardiac-specific Atg5 overexpression restrained melatonin alleviation of pressure overload-induced cardiac hypertrophy. These results demonstrated that melatonin ameliorated pressure overload-induced cardiac hypertrophy by attenuating Atg5-dependent autophagy and activating the Akt/mTOR pathway.

Valproic Acid Increased Autophagic Flux in human Multiple Myeloma Cells in Vitro

BACKGROUND

To investigate the effects of valproic acid (VPA) on autophagic flux in multiple myeloma (MM) cells.

METHODS AND RESULTS

Cell proliferation was assayed by the Cell Counting Kit-8 assay. The qRT-PCR was used to measure the expressions of LC3-II at mRNA level. Autophagic flux was measured by LC3-II turnover using western blot analysis and flow cytometry using the fluorescent dye Cyto-ID. An assay using the RFP-GFP-LC3 tandem construct was performed to monitor autophagic flux. Cell proliferation assay showed that VPA could inhibit the proliferation of MM cells and the inhibitory effects were enhanced with the extension of time. The qRT-PCR and western blot showed that the expression level of LC3-II in the VPA plus CQ group was significantly higher than that in CQ group. Cyto-ID autophagy test showed that the intracellular average fluorescence intensity in VPA plus CQ group was significantly higher than that in control and VPA group (all p < 0.001). The results of RFP-GFP-LC3 tandem construct showed that the numbers of yellow puncta and red puncta in VPA group was higher than that in control group.

CONCLUSIONS

VPA could inhibit the proliferation of MM cells and the inhibitory effects were enhanced with the extension of time. VPA could enhance autophagic flux in MM cells, and the increase of autophagosomes was caused by autophagy enhancement rather than inhibition. These findings provided rationale for the treatment of MM with VPA.

Neuroprotection by Walnut-Derived Peptides through Autophagy Promotion via Akt/mTOR Signaling Pathway against Oxidative Stress in PC12 Cells

Natural-derived peptides are effective substances in attenuating oxidative stress. However, their specific mechanisms have not been fully elucidated, especially in peptide-mediated autophagy. In the present study, TWLPLPR, YVLLPSPK, and KVPPLLY, novel peptides from Juglans mandshurica Maxim, prevented reactive oxygen species (ROS) production, elevated glutathione peroxidase (GSH-Px) activity and adenosine 5'-triphosphate (ATP) levels, and ameliorated apoptosis in Aβ_25-35 (at a concentration of 50 μM for 24 h)-induced PC12 cells (P < 0.01). Both western blot and immunofluorescence analysis illustrated that the peptides regulated Akt/mTOR signaling through p-Akt (Ser473) and p-mTOR (S2481) and promoted autophagy by increasing the levels of LC3-II/LC3-I and Beclin-1 while lowering p62 expression (P < 0.01). The autophagy inhibitor (3-methyladenine, 3-MA) and inducer (rapamycin, RAPA) were combined used to confirm the contribution of peptide-regulated autophagy in antioxidative effects. Moreover, the peptides increased the levels of LAMP1, LAMP2, and Cathepsin D (P < 0.05) and promoted the fusion with lysosomes to form autolysosomes, accelerating ROS removal. These data suggested that walnut-derived peptides regulated oxidative stress by promoting autophagy in the Aβ_25-35-induced PC12 cells.

Sodium valproate attenuates the iE-DAP induced inflammatory response by inhibiting the NOD1-NF-κB pathway and histone modifications in bovine mammary epithelial cells

The anti-inflammatory effects of sodium valproate (VPA) in vivo and in vitro have been demonstrated in recent studies. The aim of this study was to evaluate whether VPA can suppress inflammation in bovine mammary epithelial cells (BMECs) stimulated by γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP). First, the concentration and treatment points of iE-DAP and VPA were optimized. Then, BMECs were cultured in complete media and separated into four groups: untreated control cells (CON group), cells stimulated by 10 μg/mL iE-DAP for 6 h (DAP group), cells stimulated by 0.5 mmol/L VPA for 6 h (VPA group), and cells pretreated with VPA (0.5 mmol/L) for 6 h followed by 10 μg/mL of iE-DAP for 6 h (VD group). The results showed that the level of  interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the culture medium increased in the iE-DAP-treated cells and that pretreatment with VPA reversed this increase. iE-DAP increased both mRNA and protein expression levels of nucleotide-binding oligomerization domain-containing protein 1 (NOD1) and receptor-interacting protein kinas (RIPK2) and activated inhibitor of NF-κB (IκB) and nuclear factor-kappa B p65 (NF-κB p65) through phosphorylation. Upon activation of the NF-κB pathway, the expression of the pro-inflammatory cytokines IL-6, interleukin-8 (IL-8) and interleukin-1β (IL-1β), the acute phase protein serum amyloid A 3 (SAA3) and the lingual antimicrobial peptide (LAP) but not  haptoglobi (HP) or bovine neutrophil beta defensing 5 (BNBD5) were increased in the DAP group. The VPA pretreatment induced the acetylation of signal transducers and activators of transcription(STAT1) and histone 3 (H3) by inhibiting histone deacetylase (HDAC) and then suppressed the NF-κB pathway. Moreover, VPA induced autophagy and reduced apoptosis in BMECs in the VD group. These results suggested that VPA treatment can attenuate the inflammatory response induced by iE-DAP.