Apigenin suppresses TGF-β1-induced cardiac fibroblast differentiation and collagen synthesis through the downregulation of HIF-1α expression by miR-122-5p

Predictive value of HIF-1α for left ventricular remodeling following an anterior ST-segment elevation myocardial infarction

BACKGROUND

Hypoxia-inducible factor-1α (HIF-1α) has an essential role in ventricular remodeling processes involving myocardial fibrosis and hypertrophy, but the clinical significance of HIF-1α levels in the early period after ST-segment elevation myocardial infarction (STEMI) for the prediction of left ventricular remodeling (LVR) has yet to be fully elucidated.

OBJECTIVE

To investigate the predictive value of HIF-1α for LVR after STEMI based on the echocardiographic parameters.

METHODS

In this prospective observational study, plasma samples were collected within 12 hours of onset from 183 patients with a first reperfused anterior ST-segment elevation myocardial infarction (STEMI), and HIF-1α levels were measured using enzyme-linked immunosorbent assay (ELISA). At baseline and 12 months after discharge, all patients underwent repeat echocardiography. The changes of echocardiography parameters from baseline to 12 months were used to reflect the changes of ventricular structure and function. An increase in end-diastolic volume of ≥20 % was defined as LVR.

RESULTS

The levels of HIF-1α were highly correlated with the changes of echocardiography parameters (ΔLVEF, ΔLVEDD, as well as ΔLVEDV). During the follow-up period, patients with higher HIF-1α concentrations had higher incidence of LVR, poorer ventricular function, and a lower MACE-free survival. Multivariate analysis showed the single-point HIF-1α was an independent predictor of LVR (odds ratio[OR]: 4.813; 95 % CI: 1.553 to 14.918; P = 0.006). The HIF-1α levels predicted LVR with an AUC of 0.7905 (95 % CI: 0.7067 to 0.8744; P < 0.0001). The combination of HIF-1α and N-terminal probrain natriuretic peptide (NT-proBNP) yielded a favorable increase in AUC to 0.8121 (95 % CI: 0.7345 to 0.8896; P < 0.0001).

CONCLUSION

These results demonstrate that serum HIF-1α levels can predict LVR after STEMI independently.

Ncl liquid-liquid phase separation and SUMOylation mediate the stabilization of HIF-1α expression and promote pyroptosis in ischemic hindlimb

Liquid-liquid phase separation (LLPS) has emerged as a flexible intracellular compartment that modulates various pathological processes. Hypoxia-inducible factor-1α (HIF-1α) has been shown to play an essential role in inflammation after ischemic injury. However, the mechanisms underlying HIF-1α-induced inflammation in ischemic diseases have not been defined. This study found that HIF-1α mediated the progression of ischemia-induced muscle injury. After ischemic injury, SUMO1 is upregulated and rapidly activates NLRP3 inflammasome through the upregulation of HIF-1α, leading to enhanced inflammation and pyroptosis. Co-IP revealed an interaction between SUMO1 and HIF-1α and SUMOylation of HIF-1α at K477. Moreover, we demonstrated the important role of dynamic phase separation of Nucleolin (Ncl) in regulating HIF-1α mRNA stability through fluorescence recovery after photobleach (FRAP) analysis. The stability of HIF-1α is regulated by Ncl liquid-liquid phase separation and SUMOylation in ischemia-induced hindlimb injury. HIF-1α can promote the expression of NLRP3 and other inflammation-related molecules, leading to pyroptosis, suggesting that Ncl/LLPS/HIF-1α or SUMO1/HIF-1α pathway may be a new target for the treatment of inflammation in ischemic diseases. Although previous studies have found that HIF-1α is able to promote the expression of target genes after hypoxia, and these genes are used to maintain the stability of the intracellular environment to adapt to hypoxia. We found that HIF-1α is involved in the activation process of NLRP3 inflammasomes after hind limb ischemia, which enriches our understanding of the biological role of HIF-1α.

Interplay Between Polyphenols and Autophagy: Insights From an Aging Perspective

The relationship between polyphenols and autophagy, particularly in the context of aging, presents a promising avenue for therapeutic interventions in age-related diseases. A decline in autophagy is associated with aging-related affections, and an increasing number of studies suggest that this enhancement is linked to cellular resilience and longevity. This review delves into the multifaceted roles of autophagy in cellular homeostasis and the potential of polyphenols to modulate autophagic pathways. We revised the most updated literature regarding the modulatory effects of polyphenols on autophagy in cardiovascular, liver, and kidney diseases, highlighting their therapeutic potential. We highlight the role of polyphenols as modulators of autophagy to combat age-related diseases, thus contributing to improving the quality of life in aging populations. A better understanding of the interplay of autophagy between autophagy and polyphenols will help pave the way for future research and clinical applications in the field of longevity medicine.

Regulatory Roles and Therapeutic Potential of miR-122-5p in Hypoxic-Ischemic Brain Injury: Comprehensive Review

In the regulation of gene expression, epigenetic factors, including non-coding RNAs (ncRNAs) play a role in genetics. Among the ncRNA family, microRNAs (miRNAs) have gained significant attention for their involvement in post-transcriptional gene regulation, with profound implications for both normal and pathological processes including neurological diseases such as hypoxic-ischemic brain injury. A specific miRNA, called miR-122-5p, has gained attention in hypoxic-ischemic conditions, where it modulates critical pathways such as inflammation, oxidative stress, and neuronal survival. The purpose of this review is to highlight recent advances in the biogenesis, expression, and regulation of miR-122-5p, focusing on its role in hypoxic-ischemic conditions and its potential as a therapeutic target. We first studied the therapeutic strategies and potential clinical applications of miR-122-5p, our research showing it interacts with key transcription factors, such as HIF-1α and NF-κB, influencing cellular responses to low oxygen levels. Our findings revealed that miR-122-5p plays a vital role in hypoxic-ischemic brain injury, with its abnormal levels strongly associated with increased brain damage and neuroinflammation, suggesting its potential as a promising therapeutic target. Furthermore, miR-122-5p influences various biological processes in the brain, such as metabolism and blood vessel formation. The use of miR-122-5p inhibitor has been shown to increase autophagy, reduce apoptosis, and decrease oxidative stress and inflammation, thereby protecting neurons and improving outcomes in hypoxic encephalopathy by targeting multiple genes related to these processes. Conversely, miR-122-5p mimics exacerbate oxidative stress and reduce autophagy. These findings highlight the therapeutic potential of miR-122-5p inhibition in reducing brain injury and promoting recovery in hypoxic-ischemic encephalopathy through enhanced neuroprotective mechanisms and the suppression of harmful cellular processes. However, further experimental studies are needed to fully understand the therapeutic potential of targeting miR-122-5p and its related genes in hypoxic-ischemic encephalopathy.

The PKM2/HIF-1α Axis is Involved in the Pathogenesis of Endometriosis via TGF-β1 under Endometrial Polyps

BACKGROUND

Endometriosis patients exhibit a cancer-like glycolytic phenotype. The pyruvate kinase M2 (PKM2)/hypoxia-inducible factor-1 alpha (HIF-1α) axis plays important roles in glycolysis-related diseases, but its role in patients with endometrial polyps (EPs) combined with endometriosis has not been validated.

METHODS

EP samples were collected from patients with and without endometriosis. PKM2, HIF-1α, and transforming growth factor-beta 1 (TGF-β1) levels were detected by immunohistochemistry (IHC), quantitative polymerase chain reaction, western blotting, and/or immunofluorescence. Primary endometrial stromal cells (ESCs) and non-endometriotic patient-derived ESCs (NESCs) were isolated from patients with EP with or without endometriosis. PKM2 loss-of-function assays in ESCs and gain-of-function assays in NESCs were performed to assess the function of PKM2. The effects of PKM2 and TGF-β1 on the promoter activity of HIF-1α were determined by dual-luciferase reporter assay.

RESULTS

PKM2 was overexpressed in ESCs compared to NESCs. Furthermore, PKM2 knockdown repressed viability, decreased migration and invasion, and restrained glycolysis of ESCs, accompanied by reduced HIF-1α levels and weakened promoter activity of HIF-1α. In addition, PKM2 overexpression had the opposite effect on these indicators in NESCs. Of note, an anti-TGF-β1 Ab reversed the PKM2-overexpression-mediated effects on cell viability, migration, and invasion, but not glycolysis or HIF-1α promoter activity, in NESCs. Additionally, PKM2, HIF-1α, and TGF-β1 levels were higher in EP samples with endometriosis than in EP samples without endometriosis, and there were positive correlations between PKM2, HIF-1α, and TGF-β1 IHC scores in all EP samples.

CONCLUSIONS

PKM2/HIF-1α-axis-dependent glycolysis participates in the pathogenesis of EP combined with endometriosis by mediating TGF-β1 signaling.

Interleukin-11 drives fibroblast metabolic reprogramming in crystalline silica-induced lung fibrosis

Environmental exposure to crystalline silica (CS) particles is common and occurs during natural, industrial, and agricultural activities. Prolonged inhalation of CS particles can cause silicosis, a serious and incurable pulmonary fibrosis disease. However, the underlying mechanisms remain veiled. Herein, we aim to elucidate the novel mechanisms of interleukin-11 (IL-11) driving fibroblast metabolic reprogramming during the development of silicosis. We observed that CS exposure induced lung fibrosis in mice and activated fibroblasts, accompanied by increased IL-11 expression and metabolic reprogramming switched from mitochondrial respiration to glycolysis. Besides, we innovatively uncovered that elevated IL-11 promoted the glycolysis process, thereby facilitating the fibroblast-myofibroblast transition (FMT). Mechanistically, CS-stimulated IL-11 activated the extracellular signal-regulated kinase (ERK) pathway and the latter increased the expression of hypoxia inducible factor-1α (HIF-1α) via promoting the translation and delaying the degradation of the protein. HIF-1α further facilitated glycolysis, driving the FMT process and ultimately the formation of silicosis. Moreover, either silence or neutralization of IL-11 inhibited glycolysis augmentation and attenuated CS-induced lung myofibroblast generation and fibrosis. Overall, our findings elucidate the role of IL-11 in promoting fibroblast metabolic reprogramming through the ERK-HIF-1α axis during CS-induced lung fibrosis, providing novel insights into the molecular mechanisms and potential therapeutic targets of silicosis.

Role of TRIM59 in regulating PPM1A in the pathogenesis of silicosis and the intervention effect of tanshinone IIA

This study examines the involvement of TRIM59 in silica-induced pulmonary fibrosis and explores the therapeutic efficacy of Tanshinone IIA (Tan IIA). In vivo experiments conducted on rats with silica-induced pulmonary fibrosis unveiled an increase in TRIM59 levels and a decrease in PPM1A levels. Subsequent investigations using in vitro silicosis cell models demonstrated that modulation of TRIM59 expression significantly impacts silicosis fibrosis, influencing the levels of PPM1A and activation of the Smad2/3 signaling pathway. Immunofluorescence and co-immunoprecipitation assays confirmed the interaction between TRIM59 and PPM1A in fibroblasts, wherein TRIM59 facilitated the degradation of PPM1A protein via proteasomal and ubiquitin-mediated pathways. Furthermore, employing a rat model of silica-induced pulmonary fibrosis, Tan IIA exhibited efficacy in mitigating lung tissue damage and fibrosis. Immunohistochemical analysis validated the upregulation of TRIM59 and downregulation of PPM1A in silica-induced pulmonary fibrosis, which Tan IIA alleviated. In vitro studies elucidated the mechanism by which Tan IIA regulates the Smad2/3 signaling pathway through TRIM59-mediated modulation of PPM1A. Treatment with Tan IIA in silica-induced fibrosis cell models resulted in concentration-dependent reductions in fibrotic markers and attenuation of relevant protein expressions. Tan IIA intervention in silica-induced fibrosis cell models mitigated the TRIM59-induced upregulation of fibrotic markers and enhanced PPM1A expression, thereby partially reversing Smad2/3 activation. Overall, the findings indicate that while overexpression of TRIM59 may activate the Smads pathway by suppressing PPM1A expression, treatment with Tan IIA holds promise in counteracting these effects by inhibiting TRIM59 expression.

Unraveling the pharmacodynamic substances and possible mechanism of Trichosanthis Pericarpium in the treatment of coronary heart disease based on plasma pharmacochemistry, network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Coronary heart disease (CHD) is a chronic disease that seriously threatens people's health and even their lives. Currently, there is no ideal drug without side effects for the treatment of CHD. Trichosanthis Pericarpium (TP) has been used for several years in the treatment of diseases associated with CHD. However, there is still a need for systematic research to unravel the pharmacodynamic substances and possible mechanism of TP in the treatment of coronary heart.

AIM OF THE STUDY

The purpose of current study was to explore the pharmacodynamic substances and potential mechanisms of TP in the treatment of CHD via integrating network pharmacology with plasma pharmacochemistry and experimental validation.

MATERIALS AND METHODS

The effect of TP intervention in CHD was firstly assessed on high-fat diet combined with isoprenaline-induced CHD rats and H2O2-induced H9c2 cells, respectively. Then, the LC-MS was utilized to identify the absorbed components of TP in the plasma of CHD rats, and this was used to develop a network pharmacology prediction to obtain the possible active components and mechanisms of action. Molecular docking and immunohistochemistry were used to explore the interaction between TP and key targets. Subsequently, the efficacy of the active ingredients was investigated by in vitro cellular experiments, and their metabolic pathways in CHD rats were further analyzed.

RESULTS

The effects of TP on amelioration of CHD were verified by in vivo and in vitro experiments. Plasma pharmacochemistry and network pharmacology screened six active components in plasma including apigenin, phenylalanine, quercetin, linoleic acid, luteolin, and tangeretin. The interaction of these compounds with potential key targets AKT1, IL-1β, IL-6, TNF-α and VEGFA were preliminarily verified by molecular docking. And immunohistochemical results showed that TP reduced the expression of AKT1, IL-1β, IL-6, TNF-α and VEGFA in CHD rat hearts. Then cellular experiments confirmed that apigenin, phenylalanine, quercetin, linoleic acid, luteolin, and tangeretin were able to reduce the ROS level in H2O2-induced HUVEC cells and promote the migration and tubule formation of HUVEC cells, indicating the pharmacodynamic effects of the active components. Meanwhile, the metabolites of TP in CHD rats suggested that the pharmacological effects of TP might be the result of the combined effects of the active ingredients and their metabolites.

CONCLUSION

Our study found that TP intervention in CHD is characterized by multi-component and multi-target regulation. Apigenin, phenylalanine, linoleic acid, quercetin, luteolin, and tangeretin are the main active components of TP. TP could reduce inflammatory response and endothelial damage by regulating AKT1, IL-1β, IL-6, TNF-α and VEGFA, reduce ROS level to alleviate the oxidative stress situation and improve heart disease by promoting angiogenesis to regulate endothelial function. This study also provides an experimental and scientific basis for the clinical application and rational development of TP.

Metabolite and protein shifts in mature erythrocyte under hypoxia

As the only cell type responsible for oxygen delivery, erythrocytes play a crucial role in supplying oxygen to hypoxic tissues, ensuring their normal functions. Hypoxia commonly occurs under physiological or pathological conditions, and understanding how erythrocytes adapt to hypoxia is fundamental for exploring the mechanisms of hypoxic diseases. Additionally, investigating acute and chronic mountain sickness caused by plateaus, which are naturally hypoxic environments, will aid in the study of hypoxic diseases. In recent years, increasingly developed proteomics and metabolomics technologies have become powerful tools for studying mature enucleated erythrocytes, which has significantly contributed to clarifying how hypoxia affects erythrocytes. The aim of this article is to summarize the composition of the cytoskeleton and cytoplasmic proteins of hypoxia-altered erythrocytes and explore the impact of hypoxia on their essential functions. Furthermore, we discuss the role of microRNAs in the adaptation of erythrocytes to hypoxia, providing new perspectives on hypoxia-related diseases.

Hypoxia-inducible factor-1: Regulatory mechanisms and drug therapy in myocardial infarction

Myocardial infarction (MI), an acute cardiovascular disease characterized by coronary artery blockage, inadequate blood supply, and subsequent ischemic necrosis of the myocardium, is one of the leading causes of death. The cellular, physiological, and pathological responses following MI are complex, involving multiple intertwined pathological mechanisms. Hypoxia-inducible factor-1 (HIF-1), a crucial regulator of hypoxia, plays a significant role in of the development of MI by modulating the behavior of various cells such as cardiomyocytes, endothelial cells, macrophages, and fibroblasts under hypoxic conditions. HIF-1 regulates various post-MI adaptive reactions to acute ischemia and hypoxia through various mechanisms. These mechanisms include angiogenesis, energy metabolism, oxidative stress, inflammatory response, and ventricular remodeling. With its crucial role in MI, HIF-1 is expected to significantly influence the treatment of MI. However, the drugs available for the treatment of MI targeting HIF-1 are currently limited, and most contain natural compounds. The development of precision-targeted drugs modulating HIF-1 has therapeutic potential for advancing MI treatment research and development. This study aimed to summarize the regulatory role of HIF-1 in the pathological responses of various cells following MI, the diverse mechanisms of action of HIF-1 in MI, and the potential drugs targeting HIF-1 for treating MI, thus providing the theoretical foundations for potential clinical therapeutic targets.

PEG-modified nano liposomes co-deliver Apigenin and RAGE-siRNA to protect myocardial ischemia injury

Ischemic heart disease (IHD) is a cardiac disorder in which myocardial damage occurs as a result of myocardial ischemia and hypoxia. Evidence suggests that oxidative stress and inflammatory responses are critical in the development of myocardial ischemia. Therefore, the combination of antioxidant and anti-inflammatory applications is an effective strategy to combat ischemic heart disease. In this paper, polyethylene glycol (PEG)-modified cationic liposomes were used as carriers to deliver apigenin (Apn) with small interfering RNA (siRNA) targeting the receptor for glycosylation end products (RAGE) (siRAGE) into cardiomyocytes to prevent myocardial ischemic injury through antioxidant and anti-inflammatory effects. Our results showed that we successfully prepared cationic PEG liposomes loaded with Apn and siRAGE (P-CLP-A/R) with normal appearance and morphology, particle size and Zeta potential, and good encapsulation rate, drug loading and in vitro release degree. In vitro, P-CLP-A/R was able to prevent oxidative stress injury in H9C2 cells, downregulate the expression of RAGE, reduce the secretion of cellular inflammatory factors and inhibit apoptosis through the RAGE/NF-κB pathway; In vivo, P-CLP-A/R was able to prevent arrhythmia and myocardial pathological injury, and reduce apoptosis and the area of necrotic myocardium in rats. In conclusion, P-CLP-A/R has a protective effect on myocardial ischemic injury and is expected to be a potential drug for the prevention of ischemic heart disease in the future.

MiR-122 knockdown regulates vascular smooth muscle cells phenotypic switching through enhanced FOXO3 expression

Vascular smooth muscle cells (VSMCs) phenotypic switching is identified as enhanced dedifferentiation, proliferation, and migration ability of VSMCs, in which microRNAs have been identified as important regulators of the process. The present study is aimed to explore the pathophysiological effect of miR-122 on VSMC phenotypic modulation. Here, the result showed that the decreased miR-122 expression was found in VSMCs subjected to platelet-derived growth factor-BB (PDGF-BB) treatment. Next, we investigated the response of miR-122 knockdown in VSMCs with PDGF-BB stimulation. MiR-122 silencing showed increased proliferation and migration capability, whereas attenuated the differentiation markers expression. The above results were reversed by miR-122 overexpression. Finally, we further demonstrated that FOXO3 was an important target for miR-122. Collectively, we demonstrated that miR-122 silencing promoted VSMC phenotypic modulation partially through upregulated FOXO3 expression that indicated miR-122 may be a novel therapeutic target for neointimal formation.

MicroRNA-122-5p alleviates endometrial fibrosis via inhibiting the TGF-β/SMAD pathway in Asherman's syndrome

RESEARCH QUESTION

What is the effect of miR-122 on the progression and recovery of fibrosis in Asherman's syndrome?

DESIGN

Endometrial tissue was collected from 21 patients, 11 with intrauterine adhesion (IUA) and 10 without IUA. Quantitative real-time polymerase chain reaction, immunofluorescence and Western blot were applied to observe the expression of mRNAs/miRNAs and protein, respectively. The endometrial physical injury was carried out in C57BL/6 mice to create an endometrial fibrosis model, with intrauterine injection of adenovirus to compare the antifibrosis and repair function of miR-122 on endometrium. The morphology of the uterus was observed using haematoxylin and eosin staining, and fibrosis markers were detected by immunohistochemistry.

RESULTS

miR-122 expression was reduced in patients with IUAs, accompanied by fibrosis. MiR-122 overexpression reduced the degree of fibrosis in endometrial stromal cells. Further molecular analyses demonstrated that miR-122 inhibited fibrosis through the TGF-β/SMAD pathway by directly targeting the 3' untranslated region of SMAD family member 3, suppressing its expression. Notably, miR-122 promoted endometrial regeneration and recovery of pregnancy capacity in a mouse endometrial injury model.

CONCLUSIONS

miR-122 is a critical regulator for repair of endometrial fibrosis and provided new insight for the clinical treatment of intrauterine adhesions.

PDK4 facilitates fibroblast functions and diabetic wound healing through regulation of HIF-1α protein stability and gene expression

Fibroblast activation disorder is one of the main pathogenic characteristics of diabetic wounds. Orchestrated fibroblast functions and myofibroblast differentiation are crucial for wound contracture and extracellular matrix (ECM) formation. Pyruvate dehydrogenase kinase 4 (PDK4), a key enzyme regulating energy metabolism, has been implicated in modulating fibroblast function, but its specific role in diabetic wounds remains poorly understood. In this study, we investigated the impact of PDK4 on diabetic wounds and its underlying mechanisms. To assess the effect of PDK4 on human dermal fibroblasts (HDFs), we conducted CCK-8, EdU proliferation assay, wound healing assay, transwell assay, flow cytometry, and western blot analyses. Metabolic shifts were analyzed using the Seahorse XF analyzer, while changes in metabolite expression were measured through LC-MS. Local recombinant PDK4 administration was implemented to evaluate its influence on wound healing in diabetic mice. Finally, we found that sufficient PDK4 expression is essential for a normal wound-healing process, while PDK4 is low expressed in diabetic wound tissues and fibroblasts. PDK4 promotes proliferation, migration, and myofibroblast differentiation of HDFs and accelerates wound healing in diabetic mice. Mechanistically, PDK4-induced metabolic reprogramming increases the level of succinate that inhibits PHD2 enzyme activity, thus leading to the stability of the HIF-1α protein, during which process the elevated HIF-1α mRNA by PDK4 is also indispensable. In conclusion, PDK4 promotes fibroblast functions through regulation of HIF-1α protein stability and gene expression. Local recombinant PDK4 administration accelerates wound healing in diabetic mice.

Thymoquinone affects the gemcitabine sensitivity of pancreatic cancer by regulating collagen via hypoxia inducible factor-1α

Objective: To clarify the potential therapeutic effects of thymoquinone (TQ) on pancreatic cancer and its gemcitabine (GEM) sensitivity. Methods: The expression levels of hypoxia inducible factor-1α (HIF-1α), collagens (COL1A1, COL3A1, and COL5A1), and transforming growth factor-β1 (TGFβ1) in pancreatic cancer and para-carcinoma tissues were compared using immunohistochemical methods, and their relationships with TNM staging were analyzed. The effects of TQ on apoptosis, migration, invasion, and GEM sensitivity of pancreatic cancer cells were assessed using in vitro and in vivo experiments. Western blot and immunohistochemistry were used to detect the expression levels of HIF-1α, extracellular matrix (ECM) production pathway-related proteins, and TGFβ/Smad signaling pathway-related proteins. Results: The expression levels of HIF-1α, COL1A1, COL3A1, COL5A1, and TGFβ1 in pancreatic cancer tissues were significantly higher than those in para-carcinoma tissues and correlated with TNM staging (p < 0.05). TQ and GEM administration inhibited the migration and invasion of the human pancreatic cancer cell line PANC-1 and promoted the apoptosis of PANC-1 cells. The combination of TQ and GEM was more effective than GEM alone. Western blot analysis showed that the expression levels of HIF-1α, ECM production pathway-related proteins, and TGFβ/Smad signaling pathway-related proteins were significantly decreased when TQ was used to treat PANC-1 cells (p < 0.05), and the expression levels of these proteins in the TQ + GEM group were significantly more decreased than those in the GEM group. Overexpression or knockdown of HIF-1α in PANC-1 cells showed the same effects as those induced by TQ administration. In vivo experiments showed that in PANC-1 tumor-bearing mice, tumor volume and tumor weight in mice treated with GEM and TQ were significantly lower than those in control or GEM-treated mice, whereas cell apoptosis was significantly increased (p < 0.05). Western blot and immunohistochemistry results showed that the levels of HIF-1α, ECM production pathway-related proteins, and TGFβ/Smad signaling pathway-related proteins in the GEM + TQ treatment group were further decreased compared to the control group or the GEM treatment group (p < 0.05). Conclusion: In pancreatic cancer cells, TQ can promote apoptosis, inhibit migration, invasion, and metastasis, and enhance the sensitivity to GEM. The underlying mechanism may involve the regulation of ECM production through the TGFβ/Smad pathway, in which HIF-1α plays a key role.

Inhibitory effect of miR-138-5p on choroidal fibrosis in lens-induced myopia guinea pigs via suppressing the HIF-1α signaling pathway

Myopia is one of the most common eye diseases in children and adolescents worldwide. Currently, there is no effective treatment in clinical practice. Ocular tissue fibrosis is involved in the development of myopia and this study aimed to investigate the effect of miR-138-5p on choroidal fibrosis in myopic guinea pigs via regulating the HIF-1α signaling pathway. First, guinea pigs were randomly divided into a normal control (NC) group, a lens-induced myopia (LIM) group, a LIM + miR-138-5p-carried Lentivirus treatment (LV) group, and a LIM + miR-138-5p-Vector treatment (VECTOR) group. All animals were induced experimental myopia with a -6.0 diopter lens except those in the NC group. Meanwhile, animals in the LV group were supplemented with 5 μl of miR-138-5p-carried Lentivirus, while those in the VECTOR group were only supplemented with the same volume of miR-138-5p-Vector. After myopia induction for 2 and 4 weeks, the refractive status and other ocular parameters of the guinea pigs were measured. Further, the expression of hypoxia-inducible factor (HIF)-1α, transforming growth factor (TGF)-β, collagen I, hydroxyproline (HYP), interleukin 1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and a-smooth muscle actin (α-SMA) in choroidal tissues was investigated. Results showed that the refraction and axial length of the experimental myopic guinea pigs increased, and choroid fibrosis aggravated after experimental myopic induction. miR-138-5p can efficiently decrease the refraction and ocular length, and ameliorate the choroidal fibrosis of the experimental myopic guinea pigs via downregulating the fibrosis-related TGF-β1, collagen I, HYP, IL-1β, TNF-α, and α-SMA expression through inhibiting the HIF-1α signaling pathway. Our results provide new insight into controlling myopic development using microRNAs in clinical practice.

Apigenin alleviates oxidative stress-induced myocardial injury by regulating SIRT1 signaling pathway

Apigenin is a natural flavonoid which is widely found in vegetables and fruits. However, the mechanism of apigenin in oxidative stress-induced myocardial injury has not been fully elucidated. We established an isoproterenol (Iso)-induced myocardial injury mouse model and a hypoxia/reoxygenation (H/R)-induced H9c2 cell injury model, followed by pretreatment with apigenin to explore its protective effects. Apigenin can significantly alleviate isoproterenol-induced oxidative stress, cell apoptosis and myocardial remodeling in vivo. Apigenin pretreatment can also significantly improve cardiomyocyte morphology, decrease H/R induced oxidative stress, and attenuate cell apoptosis and inflammation in vitro. Further mechanism study revealed that apigenin treatment reversed isoprenaline and H/R-induced decrease of Sirtuin1 (SIRT1). Molecular docking results proved that apigenin can form hydrogen bond with 230 Glu, a key site of SIRT1 activation, indicating that apigenin is an agonist of SIRT1. Moreover, SIRT1 knockdown by siRNA significantly reversed the protective effect of apigenin in H/R-induced myocardial injury. In conclusion, apigenin protects cardiomyocyte function from oxidative stress-induced myocardial injury by modulating SIRT1 signaling pathway, which provides a new potential therapeutic natural compound for the clinical treatment of cardiovascular diseases.

Mechanism of action of non-coding RNAs and traditional Chinese medicine in myocardial fibrosis: Focus on the TGF-β/Smad signaling pathway

Cardiac fibrosis is a serious public health problem worldwide that is closely linked to progression of many cardiovascular diseases (CVDs) and adversely affects both the disease process and clinical prognosis. Numerous studies have shown that the TGF-β/Smad signaling pathway plays a key role in the progression of cardiac fibrosis. Therefore, targeted inhibition of the TGF-β/Smad signaling pathway may be a therapeutic measure for cardiac fibrosis. Currently, as the investigation on non-coding RNAs (ncRNAs) move forward, a variety of ncRNAs targeting TGF-β and its downstream Smad proteins have attracted high attention. Besides, Traditional Chinese Medicine (TCM) has been widely used in treating the cardiac fibrosis. As more and more molecular mechanisms of natural products, herbal formulas, and proprietary Chinese medicines are revealed, TCM has been proven to act on cardiac fibrosis by modulating multiple targets and signaling pathways, especially the TGF-β/Smad. Therefore, this work summarizes the roles of TGF-β/Smad classical and non-classical signaling pathways in the cardiac fibrosis, and discusses the recent research advances in ncRNAs targeting the TGF-β/Smad signaling pathway and TCM against cardiac fibrosis. It is hoped, in this way, to give new insights into the prevention and treatment of cardiac fibrosis.

Pharmacological and Molecular Insight on the Cardioprotective Role of Apigenin

Apigenin is a naturally occurring dietary flavonoid found abundantly in fruits and vegetables. It possesses a wide range of biological properties that exert antioxidant, anti-inflammatory, anticancer, and antibacterial effects. These effects have been reported to be beneficial in the treatment of atherosclerosis, stroke, hypertension, ischemia/reperfusion-induced myocardial injury, and diabetic cardiomyopathy, and provide protection against drug-induced cardiotoxicity. These potential therapeutic effects advocate the exploration of the cardioprotective actions of apigenin. This review focuses on apigenin, and the possible pharmacological mechanisms involved in the protection against cardiovascular diseases. We further discuss its therapeutic uses and highlight its potential applications in the treatment of various cardiovascular disorders. Apigenin displays encouraging results, which may have implications in the development of novel strategies for the treatment of cardiovascular diseases. With the commercial availability of apigenin as a dietary supplement, the outcomes of preclinical studies may provide the investigational basis for future translational strategies evaluating the potential of apigenin in the treatment of cardiovascular disorders. Further preclinical and clinical investigations are required to characterize the safety and efficacy of apigenin and establish it as a nutraceutical as well as a therapeutic agent to be used alone or as an adjuvant with current drugs.

Targeting epigenetics in diabetic cardiomyopathy: Therapeutic potential of flavonoids

The pathophysiological mechanisms of diabetic cardiomyopathy have been extensively studied, but there is still a lack of effective prevention and treatment methods. The ability of flavonoids to protect the heart from diabetic cardiomyopathy has been extensively described. In recent years, epigenetics has received increasing attention from scholars in exploring the etiology and treatment of diabetes and its complications. DNA methylation, histone modifications and non-coding RNAs play key functions in the development, maintenance and progression of diabetic cardiomyopathy. Hence, prevention or reversal of the epigenetic alterations that have occurred during the development of diabetic cardiomyopathy may alleviate the personal and social burden of the disease. Flavonoids can be used as natural epigenetic modulators in alternative therapies for diabetic cardiomyopathy. In this review, we discuss the epigenetic effects of different flavonoid subtypes in diabetic cardiomyopathy and summarize the evidence from preclinical and clinical studies that already exist. However, limited research is available on the potential beneficial effects of flavonoids on the epigenetics of diabetic cardiomyopathy. In the future, clinical trials in which different flavonoids exert their antidiabetic and cardioprotective effects through various epigenetic mechanisms should be further explored.

RNA sequencing-based identification of the regulatory mechanism of microRNAs, transcription factors, and corresponding target genes involved in vascular dementia

Vascular dementia (VaD) is the second most common form of dementia with uncertain mechanisms and no effective treatments. microRNAs (miRNAs) and transcription factors (TFs) are considered regulatory factors of genes involved in many diseases. Therefore, this work investigated the aberrantly expressed miRNAs, TFs, corresponding target genes, and their co-regulatory networks in the cortex of rats with bilateral common carotid artery occlusion (2VO) to uncover the potential mechanism and biomarkers of VaD. Differentially expressed genes (DEGs), miRNAs (DEMs), and TFs (DETFs) were identified using RNA sequencing, and their interaction networks were constructed using Cytoscape. The results showed that rats with 2VO had declined cognitive abilities and neuronal loss in the cortex than sham rats. DEGs, DEMs, and DETFs were discriminated between rats with 2VO and sham rats in the cortex, as shown by the 13 aberrantly expressed miRNAs, 805 mRNAs, and 63 TFs. The miRNA-TF-target gene network was constructed, showing 523 nodes and 7237 edges. Five miRNAs (miR-5132-5p, miR-764-3p, miR-223-3p, miR-145-5p, and miR-122-5p), ten TFs (Mxi1, Nfatc4, Rxrg, Zfp523, Foxj2, Nkx6-1, Klf4, Klf5, Csrnp1, and Prdm6), and seven target genes (Serpine1, Nedd4l, Pxn, Col1a1, Plec, Trip12, and Tpm1) were chosen as the significant nodes to construct feed-forward loops (FFLs). Gene Ontology and pathway enrichment analysis revealed that these miRNA and TF-associated genes are mostly involved in the PI3K/Akt, neuroactive ligand–receptor interaction, calcium signaling, and Wnt signaling pathways, along with central locations around the cell membrane. They exert functions such as growth factor binding, integrin binding, and extracellular matrix structural constituent, with representative biological processes like vasculature development, cell–substrate adhesion, cellular response to growth factor stimulus, and synaptic transmission. Furthermore, the expression of three miRNAs (miR-145-5p, miR-122-5p, and miR-5132-5p), six TFs (Csrnp1, Klf4, Nfatc4, Rxrg, Foxj2, and Klf5), and five mRNAs (Serpine1, Plec, Nedd4l, Trip12, and Tpm1) were significantly changed in rats with VaD, in line with the outcome of RNA sequencing. In the potential FFL, miR-145-5p directly bound Csrnp1 and decreased its mRNA expression. These results might help the understanding of the underlying regulatory mechanisms of miRNA-TF-genes, providing potential therapeutic targets in VaD.

Apigenin suppresses tumor angiogenesis and growth via inhibiting HIF-1α expression in non-small cell lung carcinoma

Tumor angiogenesis inhibitors such as Bevacizumab, Ramucirumab and Endostar have been applied to the therapy of non-small cell lung carcinoma (NSCLC) patients, especially for lung adenocarcinoma (LUAD). However, several safe concerns such as neutropenia, febrile neutropenia and hypertension pulmonary hemorrhage limit their further development. And they often showed poor efficacy and serious side effect for lung squamous cell carcinoma (LUSC) patient. Thus, identification of effective and safe tumor angiogenesis inhibitor for NSCLC therapy is warranted. Apigenin is a bioflavonoid with potential anti-tumor effect and perfect safety, but its effect on tumor angiogenesis and underlying mechanism are still unclear. Herein, we found that apigenin not merely suppressed endothelial cells related motilities but also reduced pericyte coverage. Further research showed that apigenin had strong suppressive activity against HIF-1α expression and its downstream VEGF-A/VEGFR2 and PDGF-BB/PDGFβR signaling pathway. Apigenin also reduced microvessel density and pericyte coverage on the xengraft model of NCI-H1299 cells, leading to suppression of tumor growth. Moreover, apigenein showed perfect anti-angiogenic effect in xengraft model of LUSC cell NCI-H1703 cells, indicating it may be developed into a potential angiogenesis inhibitor for LUSC patient. Collectively, our study provides new insights into the anti-tumor mechanism of apigenin and suggests that apigenin is a safe and effective angiogenesis inhibitor for NSCLC therapy.

Intracellular Toxic Advanced Glycation End-Products May Induce Cell Death and Suppress Cardiac Fibroblasts

Cardiovascular disease (CVD) is a lifestyle-related disease (LSRD) induced by the dysfunction and cell death of cardiomyocytes. Cardiac fibroblasts are activated and differentiate in response to specific signals, such as transforming growth factor-β released from injured cardiomyocytes, and are crucial for the protection of cardiomyocytes, cardiac tissue repair, and remodeling. In contrast, cardiac fibroblasts have been shown to induce injury or death of cardiomyocytes and are implicated in the pathogenesis of diseases such as cardiac hypertrophy. We designated glyceraldehyde-derived advanced glycation end-products (AGEs) as toxic AGEs (TAGE) due to their cytotoxicity and association with LSRD. Intracellular TAGE in cardiomyocytes decreased their beating rate and induced cell death in the absence of myocardial ischemia. The TAGE levels in blood were elevated in patients with CVD and were associated with myocardial ischemia along with increased risk of atherosclerosis in vascular endothelial cells in vitro. The relationships between the dysfunction or cell death of cardiac fibroblasts and intracellular and extracellular TAGE, which are secreted from certain organs, remain unclear. We examined the cytotoxicity of intracellular TAGE by a slot blot analysis, and TAGE-modified bovine serum albumin (TAGE-BSA), a model of extracellular TAGE, in normal human cardiac fibroblasts (HCF). Intracellular TAGE induced cell death in normal HCF, whereas TAGE-BSA did not, even at aberrantly high non-physiological levels. Therefore, only intracellular TAGE induced cell death in HCF under physiological conditions, possibly inhibiting the role of HCF.

Osthole Increases the Sensitivity of Liver Cancer to Sorafenib by Inhibiting Cholesterol Metabolism

Osthole is a natural product that has an inhibitory effect on liver cancer, but its effect on the sensitivity of liver cancer to sorafenib is poorly understood. Here, we investigated the effect of osthole and possible sensitization mechanisms. Our results showed that the combination of 2.5 μM sorafenib and 10 μM osthole had significantly synergistic inhibitory effects on proliferation, colony formation, and migration of HCCLM3, sorafenib-resistant HCCLM3 (HCCLM3-SR), and SK-Hep-1 cells. After treatment of HCCLM3 cells-inoculated subcutaneous xenotransplanted tumor mice with 100 mg/kg osthole, 70 mg/kg sorafenib or their combination for 24 day, the tumor volume, tumor weight, and tumor weight coefficient were significantly lower in the osthole + sorafenib group than in the sorafenib group. Compared with the control group, the total cholesterol and low density lipoprotein-cholesterol contents in serum and tumor tissue were significantly decreased in the osthole or osthole + sorafenib groups, the sterol regulatory element binding protein (SREBP)-2c, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), and low-density lipoprotein receptor (LDLR) protein expressions in tumor tissue were significantly downregulated as well. In conclusion, osthole can increase the sensitivity of liver cancer to sorafenib, and the mechanism is related to the downregulations of SREBP-2c, HMGCR, and LDLR protein expressions and subsequent inhibition of cholesterol metabolism.

OTUD7B (Cezanne) ameliorates fibrosis after myocardial infarction via FAK-ERK/P38 MAPK signaling pathway

Fibrosis is one of the crucial reasons for cardiac dysfunction after myocardial infarction (MI). Understanding the underlying molecular mechanism that causes fibrosis is crucial to developing effective therapy. Recently, OUT domain-containing 7B (OTUD7B), also called Cezanne, a multifunctional deubiquitylate, has been found to play various roles in cancer and vascular diseases and control many important signaling pathways, including inflammation, proliferation, and so on. However, whether OTUD7B plays a role in fibrosis caused by MI remains unclear. Our study aimed to explore the function of OTUD7B in cardiac fibrosis and investigate the underlying mechanism. We found that the expression of OTUD7B was downregulated in the MI rat model and cultured cardiac fibroblasts (CFs) in hypoxic conditions and after TGF-β1 treatment. In vitro, silencing OTUD7B using small interfering RNA (siRNA) increased α-SMA (smooth muscle actin α) and collagen Ⅰ levels in CFs, whereas the overexpression of OTUD7B using adenovirus decreased their expression. Mechanistically, OTUD7B could regulate the phosphorylation of focal adhesion kinase (FAK), a non-receptor tyrosine kinase that has been proved to act as a potential mediator of fibrosis, and ERK/P38 MAPK was involved in this regulation process. In vitro, overexpression of OTUD7B downregulated the phosphorylation level of FAK and then inhibited ERK/P38 phosphorylation, thus leading to decreased α-SMA and collagen Ⅰ expressions, while OTUD7B knockdown showed an opposite result. These findings suggest that OTUD7B could become a potentially effective therapeutic strategy against fibrosis after MI.

Apigenin inhibits isoproterenol‐induced myocardial fibrosis and Smad pathway in mice by regulating oxidative stress and miR‐122‐5p/155‐5p expressions

Apigenin, a flavonoid isolated from Apium graveolens, is an effective natural active ingredient that inhibits transforming growth factor-β1 (TGF-β1)-induced cardiac fibroblasts (CFs) differentiation and collagen synthesis. However, its effects on isoproterenol-induced myocardial fibrosis in mice remain unknown. This study aimed to examine the effect of apigenin in the prevention of myocardial fibrosis. A mouse model of myocardial fibrosis induced by isoproterenol was established, and the mice were given apigenin 75-300 mg/kg orally for 40 days. The results showed that the heart weight coefficient, myocardial hydroxyproline, collagen accumulation, and malondialdehyde levels in the apigenin-treated groups were significantly reduced. In contrast, the activity of myocardial superoxide dismutase and glutathione peroxidase were significantly enhanced. The results of real-time quantitative polymerase chain reaction and western blot assays showed that apigenin could significantly upregulate the expressions of myocardial microRNA-122-5p (miR-122-5p), c-Ski, and Smad7 and downregulate the expressions of myocardial miR-155-5p, α-smooth muscle actin, collagen I/III, NF-κB, TGF-β1, hypoxia-inducible factor-1α (HIF-1α), Smad2/3, and p-Smad2/3. In vitro, the differentiation and extracellular matrix production, as well as TGF-β1/Smads axis, were further reduced after treatment of miR-122-5p mimic or miR-155-5p inhibitor-transfected and TGF-β1-stimulated CFs with apigenin. These results suggested that apigenin increased the expression of miR-122-5p and decreased the expression of miR-155-5p, which subsequently downregulated and upregulated the target genes HIF-1α and c-Ski, respectively. Furthermore, apigenin administration downregulated TGF-β1-induced Smad2/3 and upregulated Smad7. In addition, it reduced the NF-κB/TGF-β1 signaling pathway axis by increasing antioxidant ability to exert the antifibrotic effects.

Correlation between serum miR-122 and myocardial damage and ventricular function in patients with essential hypertension

Background

Myocardial damage and decreased ventricular function are risk factors leading to a bad prognosis in patients with essential hypertension (EH). MicroRNAs play important roles in myocardial function impairment in patients with hypertension. The purpose of our research was to investigate the correlation between serum miR-122 and myocardial damage and ventricular functions in EH patients.

Methods

The clinic data of EH patients (group A, n=60) and healthy individuals (group B, n=60) from December 2016 to December 2019 in our hospital were collected and analyzed. Serum miR-122, myocardial damage markers [B-type brain natriuretic peptide (BNP), homocysteine (Hcy), cardiac troponin T (cTnT) and creatine kinase MB isoenzyme (CK-MB)] and cardiac function indicators [ejection fraction (EF), left ventricular septal thickness (IVST), left ventricular isovolumic relaxation time (IVRT), left ventricular end-diastolic diameter (LVEDD), left ventricular posterior wall thickness (LVPWT), and left ventricular end-systolic diameter (LVESD)] were assessed in both groups. The correlation between serum miR-122 and myocardial damage markers and ventricular function indicators was analyzed.

Results

(I) The mean serum miR-122 concentration in group A and group B was 6.86±1.23 and 3.36±1.87 µmol/L, respectively. The serum miR-122 concentration in group A was evidently increased compared with that in group B. (II) The levels of BNP, Hcy, cTnT, and CK-MB in the peripheral blood in group A were evidently increased compared with those in group B (P<0.05). (III) EF and IVRT were evidently decreased in group A compared with that in group B (P<0.05). (IV) Serum miR-122 concentration was positively correlated with the myocardial damage markers BNP, Hcy, cTnT and CK-MB, and serum miR-122 concentration was negatively correlated with the ventricular function indicators EF and IVRT but not significantly correlated with other ventricular function indicators (IVST, LVEDD, LVPWT and LVESD).

Conclusions

The serum miR-122 concentration in EH patients was higher than that in healthy individuals, and miR-122 concentration was positively correlated with myocardial damage markers. Serum miR-122 level was negatively correlated with the ventricular function indicators EF and IVRT but was not significantly correlated with other ventricular function indicators (IVST, LVEDD, LVPWT, and LVESD).