Apigenin attenuates TGF-β1-stimulated cardiac fibroblast differentiation and extracellular matrix production by targeting miR-155-5p/c-Ski/Smad pathway

Vitexin enhances radiosensitivity of mouse subcutaneous xenograft glioma by affecting the miR-17-5p/miR-130b-3p/PTEN/HIF-1α pathway

PURPOSE

Vitexin can cooperate with hyperbaric oxygen to sensitize the radiotherapy of glioma by inhibiting the hypoxia-inducible factor (HIF)-1α. However, whether vitexin has a direct radiosensitization and how it affects the HIF-1α expression remain unclear. This study investigated these issues.

METHODS

The SU3 cells-inoculated nude mice were divided into control, radiation, and vitexin + radiation groups. The vitexin + radiation-treated mice were intraperitoneally injected with 75 mg/kg vitexin daily for 21 days. On the 3rd, 10th, and 17th days during the vitexin treatment, the radiation-treated mice were locally irradiated with 10 Gy, respectively. In vitro, the microRNA (miR)-17-5p or miR-130b-3p mimics-transfected SU3 cells were used to examine the effects of vitexin plus radiation on expression of miR-17-5p- or miR-130b-3p-induced radioresistance-related pathway proteins. The effects of vitexin on miR-17-5p and miR-130b-3p expression in SU3 cells were also evaluated.

RESULTS

Compared with the radiation group, the tumor volume, tumor weight, and expression of HIF-1α, vascular endothelial growth factor, and glucose transporter-1/3 proteins, miR-17-5p, and miR-130b-3p in tumor tissues in the vitexin + radiation group decreased, whereas the expression of phosphatase and tensin homolog (PTEN) protein increased. After treatment of miR-17-5p or miR-130b-3p mimics-transfected SU3 cells with vitexin plus radiation, the PTEN protein expression also increased, the HIF-1α protein expression decreased correspondingly. Moreover, vitexin decreased the miR-17-5p and miR-130b-3p expression in SU3 cells.

CONCLUSION

Vitexin can enhance the radiosensitivity of glioma, and its mechanism may partly be related to the attenuation of HIF-1α pathway after lowering the inhibitory effect of miR-17-5p and miR-130b-3p on PTEN.

Enzymatic synthesis of Vaccinium blue using vaccinoside as a bifunctional precursor

Since Tang dynasty in China, the fresh leaves of Vaccinium bracteatum (VBL) have been applied as natural pigment to produce black rice. However, detailed information on its biosynthetic mechanism still remained unclear. Following rice dyeing capacity assay, vaccinoside, one of iridoid glycosides, was identified as the key active compound. Increased methodical research demonstrated vaccinoside as a distinct bifunctional precursor, which could be catalyzed by polyphenol oxidase or β-glucosidase independently, followed by reaction with 15 amino acids to give blue pigments (VBPs; λmax 581-590 nm) of different hues. Two synthetic pathways of VBPs were proposed, using multiple techniques such as HPLC, HPSEC, UV-Vis spectrum and colorimeter as analysis tools. Black rice was interpreted to be prepared by cooking, using vaccinoside, intrinsic enzymes from fresh VBL and rice protein in combination. These findings promote the understanding of VBP formation mechanisms and provide an efficient method of producing novel Vaccinium blue pigments.

Targeting extracellular matrix through phytochemicals: a promising approach of multi-step actions on the treatment and prevention of cancer

Extracellular matrix (ECM) plays a pivotal and dynamic role in the construction of tumor microenvironment (TME), becoming the focus in cancer research and treatment. Multiple cell signaling in ECM remodeling contribute to uncontrolled proliferation, metastasis, immune evasion and drug resistance of cancer. Targeting trilogy of ECM remodeling could be a new strategy during the early-, middle-, advanced-stages of cancer and overcoming drug resistance. Currently nearly 60% of the alternative anticancer drugs are derived from natural products or active ingredients or structural analogs isolated from plants. According to the characteristics of ECM, this manuscript proposes three phases of whole-process management of cancer, including prevention of cancer development in the early stage of cancer (Phase I); prevent the metastasis of tumor in the middle stage of cancer (Phase II); provide a novel method in the use of immunotherapy for advanced cancer (Phase III), and present novel insights on the contribution of natural products use as innovative strategies to exert anticancer effects by targeting components in ECM. Herein, we focus on trilogy of ECM remodeling and the interaction among ECM, cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs), and sort out the intervention effects of natural products on the ECM and related targets in the tumor progression, provide a reference for the development of new drugs against tumor metastasis and recurrence.

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.

Chamomile: A Review of Its Traditional Uses, Chemical Constituents, Pharmacological Activities and Quality Control Studies

Matricaria chamomilla L. (MC) and Chamaemelum nobile (L.) All. (CN) are two varieties of Chamomile. These herbs have been used for thousands of years in Greece, Rome and ancient Egypt. Chamomile has been used for the treatment of stomach problems, cramps, dermatitis, and minor infections. The purpose of this study was to introduce the botanical characteristics and geographical distribution, traditional uses, chemical constituents, pharmacological activities, toxicity studies and quality control studies, and lay a theoretical foundation for the rational development and utilization of chamomile. This review powered that chemical constituents include flavonoids, coumarins, volatile oils, terpenes, organic acids, polysaccharides, and others. These compounds possess anticancer, anti-infective, anti-inflammatory, antithrombotic, antioxidant, hypolipidaemic, hypoglycaemic, antihypertensive, antidepressant, neuroprotective activities, among others. Chamomile is a widely used herb in traditional medicine. It brings great economic value due to its numerous pharmacological effects and traditional uses. However, more toxicity tests should be carried out to confirm its safety. There is need for further research to provide concrete scientific evidence and validate its medicinal properties.

Virtual screening analysis of natural flavonoids as trimethylamine (TMA)-lyase inhibitors for coronary heart disease

Coronary heart disease (CHD) is defined by atherosclerosis, which can result in stenosis or blockage of the arterial cavity, leading to ischemic cardiac diseases such as angina and myocardial infarction. Accumulating evidence indicates that the gut microbiota plays a vital role in the beginning and progression of CHD. The gut microbial metabolite, trimethylamine-N-oxide (TMAO), is intimately linked to the pathophysiology of CHD. TMAO is formed when trimethylamine (TMA) is converted by flavin-containing monooxygenases in the hepatocytes. Therefore, inhibition of TMA production is essential to reduce TMAO levels. Flavonoids may reduce the risk of death from cardiovascular disease. In this article, we reviewed and evaluated twenty-two flavonoids for the therapy of CHD based on their inhibition of TMA-lyase by molecular docking. Docking results revealed that baicalein, fisetin, acacetin, and myricetin in flavonoid aglycones, and baicalin, naringin, and hesperidin in flavonoid glycosides had a good binding effect with TMA-lyase. This indicates that these chemicals were the most active and could be used as lead compounds for structural modification in the future. PRACTICAL APPLICATIONS: Flavonoids are a large class of polyphenolic compounds found in fruits, vegetables, flowers, tea, and herbal medicines, which are inexorably metabolized and transformed into bioactive metabolites by α-rhamnosidase, β-glucuronidase, β-glucosidase, and nitroreductase produced by the gut microbiota, which plays a beneficial role in the prevention and treatment of cardiovascular diseases. Because flavonoids protect the cardiovascular system and regulate the gut microbiota, and the gut microbiota is directly connected to TMAO, thus, reducing TMAO levels involves blocking the transition of TMA to TMAO, which may be performed by reducing TMA synthesis. Molecular docking results found that baicalein, fisetin, acacetin, and myricetin in flavonoid aglycones, and baicalin, naringin, and hesperidin in flavonoid glycosides had good binding effects on TMA-lyase, which were the most active and could be used as lead compounds for structural modification.

Apigenin inhibits fibrous scar formation after acute spinal cord injury through TGFβ/SMADs signaling pathway

AIM

To investigate the effect of apigenin on fibrous scar formation after mouse spinal cord injury (SCI).

METHODS

The pneumatic impactor strike method was used to establish an SCI model. Mice were intraperitoneally injected with 5 mg/kg or 20 mg/kg apigenin daily for 28 days after SCI. The Basso Mouse Scale (BMS) score, hematoxylin-eosin staining, and immunohistochemical staining were used to assess the effect of apigenin on scar formation and motor function recovery. Western blotting and qRT-PCR were used to detect the expression of fibrosis-related parameters in spinal cord tissue homogenates. NIH-3 T3 cells and mouse primary spinal cord fibroblasts, α-Smooth muscle actin (α-SMA), collagen 1, and fibronectin were used to evaluate apigenin's effect in vitro. Western blotting and immunofluorescence techniques were used to study the effect of apigenin on TGFβ/SMADs signaling.

RESULTS

Apigenin inhibited fibrous scar formation in the mouse spinal cord and promoted the recovery of motor function. It reduced the expression of fibroblast-related parameters and increased the content of nerve growth factor in vivo, decreasing myofibroblast activation and collagen fiber formation by inhibiting TGFβ-induced SMAD2/3 phosphorylation and nuclear translocation in vitro.

CONCLUSION

Apigenin inhibits fibrous scar formation after SCI by decreasing fibrosis-related factor expression through TGFβ/SMADs signaling.

Pharmacokinetic, Metabolism, and Metabolomic Strategies Provide Deep Insight Into the Underlying Mechanism of Ginkgo biloba Flavonoids in the Treatment of Cardiovascular Disease

Ginkgo biloba, known as the “living fossil,” has a long history of being used as botanical drug for treating cardiovascular diseases and the content of flavonoids as high as 24%. More than 110 different kinds of flavonoids and their derivatives have been separated from G. biloba, including flavones, flavonols, biflavonoids, catechins, and their glycosides, etc., all of which display the ability to dilate blood vessels, regulate blood lipids, and antagonize platelet activating factor, and protect against ischemic damage. At present, many types of preparations based on G. biloba extract or the bioactive flavonoids of it have been developed, which are mostly used for the treatment of cardiovascular diseases. We herein review recent progress in understanding the metabolic regulatory processes and gene regulation of cellular metabolism in cardiovascular diseases of G. biloba flavonoids. First, we present the cardioprotective flavonoids of G. biloba and their possible pharmacological mechanism. Then, it is the pharmacokinetic and liver and gut microbial metabolism pathways that enable the flavonoids to reach the target organ to exert effect that is analyzed. In the end, we review the possible endogenous pathways toward restoring lipid metabolism and energy metabolism as well as detail novel metabolomic methods for probing the cardioprotective effect of flavonoids of G. biloba.

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.

MicroRNA regulates the toxicological mechanism of four mycotoxins in vivo and in vitro

Mycotoxins can cause body poisoning and induce carcinogenesis, often with a high mortality rate. Therefore, it is of great significance to seek new targets that indicate mycotoxin activity and to diagnose and intervene in mycotoxin-induced diseases in their early stages. MicroRNAs (miRNAs) are physiological regulators whose dysregulation is closely related to the development of diseases. They are thus important markers for the occurrence and development of diseases. In this review, consideration is given to the toxicological mechanisms associated with four major mycotoxins (ochratoxin A, aflatoxin B1, deoxynivalenol, and zearalenone). The roles that miRNAs play in these mechanisms and the interactions between them and their target genes are explained, and summarize the important role of histone modifications in their toxicity. As a result, the ways that miRNAs are regulated in the pathogenicity signaling pathways are revealed which highlights the roles played by miRNAs in preventing and controlling the harmful effects of the mycotoxins. It is hoped that this review will provide a theoretical basis for the prevention and control of the damage caused by these mycotoxins.

MiRNA-Regulated Pathways for Hypertrophic Cardiomyopathy: Network-Based Approach to Insight into Pathogenesis

Hypertrophic cardiomyopathy (HCM) is the most common hereditary heart disease. The wide spread of high-throughput sequencing casts doubt on its monogenic nature, suggesting the presence of mechanisms of HCM development independent from mutations in sarcomeric genes. From this point of view, HCM may arise from the interactions of several HCM-associated genes, and from disturbance of regulation of their expression. We developed a bioinformatic workflow to study the involvement of signaling pathways in HCM development through analyzing data on human heart-specific gene expression, miRNA-target gene interactions, and protein-protein interactions, available in open databases. Genes regulated by a pool of miRNAs contributing to human cardiac hypertrophy, namely hsa-miR-1-3p, hsa-miR-19b-3p, hsa-miR-21-5p, hsa-miR-29a-3p, hsa-miR-93-5p, hsa-miR-133a-3p, hsa-miR-155-5p, hsa-miR-199a-3p, hsa-miR-221-3p, hsa-miR-222-3p, hsa-miR-451a, and hsa-miR-497-5p, were considered. As a result, we pinpointed a module of TGFβ-mediated SMAD signaling pathways, enriched by targets of the selected miRNAs, that may contribute to the cardiac remodeling in HCM. We suggest that the developed network-based approach could be useful in providing a more accurate glimpse on pathological processes in the disease pathogenesis.

Apigenin increases radiosensitivity of glioma stem cells by attenuating HIF-1α-mediated glycolysis

Apigenin, a natural flavonoid compound present in a variety of edible plants and health foods, has an anti-tumor effect and inhibits hypoxia inducible factor-lα (HIF-1α) expression in hypertrophic cardiac tissues. However, whether or not apigenin has a radiosensitization effect on glioma stem cells (GSCs) is unknown. Our present study aimed to investigate the effect of apigenin and its possible mechanisms. The human GSCs SU3 and its radioresistance line SU3-5R were treated with apigenin, radiation, or their combination, and the cell proliferation, migration, colony formation, and intracellular lactic acid and glycolytic related protein expressions were determined. Additionally, a cell model with hypoxia-induced HIF-1α expression was used and treated with apigenin. The current results displayed that the combination of apigenin and radiation could synergically reduce the viability, colony formation, and migration of the both GSCs. Moreover, this combination could also decrease the radiation-induced increments of glycolytic production lactic acid in the both GSCs and related protein expressions, including HIF-1α, glucose transporter (GLUT)-1/3, nuclear factor kappa B (NF-κB) p65, and pyruvate kinase isozyme type M2 (PKM2). Further study confirmed that after treatment of hypoxia-cultured SU3 or SU3-5R cells with apigenin, the expression levels of HIF-1α, GLUT-1/3, NF-κB p65, and PKM2 proteins were reduced. These results demonstrated that apigenin could increase the radiosensitivity of GSCs and its radiosensitization mechanisms were attributable to the attenuation of glycolysis, which might result from the inhibition of HIF-1α expression and subsequent reductions of GLUT-1/3, NF-κB, and PKM2 expressions.

Chitosan Nanoparticles Loaded with TGF-β1 Inhibit Cervical Cancer Cell Progression Through Down-Regulation of MicroRNA-155 and Activation of Tim-3 Pathway

Chemically modified chitosan nanoparticles (NPs) are capable of releasing their own substances to target cells or tissues, improving microenvironment and promoting wound healing. This study aimed to explore the molecular mechanism underlying chitosan NPs loaded with TGF-β1 participating in cervical cancer (CC) progression. TGF-β1-loaded-chitosan NPs were prepared and particle size distribution, zeta potential and encapsulation efficiency of NPs were determined. MTT assay assessed the toxicity of NPs to macrophages. CC cells were co-cultured with TGF-β1-loaded chitosan NPs (experimental group) or pure chitosan NPs (control group) and cells were cultured alone to produce control group. After treatment, flow cytometry was conducted to detect apoptosis and cycle. Cancer cell migration was evaluated by Transwell assay, and miR-155 and Tim-3 expression was determined. At a ratio of 2:1 chitosan and TGF-β1, the particle size was102.65±11.98 nm, which was smallest, with high encapsulation rate of 81.26%, and low potential of 1.46±1.71. NP toxicity increased as concentration rose and relative cell proliferation rate was >80%, indicated as non-toxic. CC tissues had positive expression of CD163 and TGF-β1 (95%) (p < 0.05). Treatment with TGF-β1-loaded chitosan NPs induced increased apoptosis rate of 9.13±2.15%, reduced migration (67.65±9.91) and invaded cells (19.98±3.41), causing cell accumulation in the S phase when compared to the blank and control groups (p < 0.05). Besides, experimental group exhibited lower expression of miR-155 (0.39±0.59) and higher expression of Tim-3 (2.87± 0.51), which was higher than the blank group and control group. The optimal concentration ratio for producing TGF-β1-loaded chitosan NPs was 2:1, with less toxicity. The composite NPs suppressed malignant characteristics of CC cells through down-regulation of miR-155 and activation of Tim-3 signal pathway on the surface of macrophages, promoting secretion of macrophage inflammatory factors.

Network pharmacology and RNA-sequencing reveal the molecular mechanism of Xuebijing injection on COVID-19-induced cardiac dysfunction

BACKGROUND

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Up to 20%-30% of patients hospitalized with COVID-19 have evidence of cardiac dysfunction. Xuebijing injection is a compound injection containing five traditional Chinese medicine ingredients, which can protect cells from SARS-CoV-2-induced cell death and improve cardiac function. However, the specific protective mechanism of Xuebijing injection on COVID-19-induced cardiac dysfunction remains unclear.

METHODS

The therapeutic effect of Xuebijing injection on COVID-19 was validated by the TCM Anti COVID-19 (TCMATCOV) platform. RNA-sequencing (RNA-seq) data from GSE150392 was used to find differentially expressed genes (DEGs) from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) infected with SARS-CoV-2. Data from GSE151879 was used to verify the expression of Angiotensin I Converting Enzyme 2 (ACE2) and central hub genes in both human embryonic-stem-cell-derived cardiomyocytes (hESC-CMs) and adult human CMs with SARS-CoV-2 infection.

RESULTS

A total of 97 proteins were identified as the therapeutic targets of Xuebijing injection for COVID-19. There were 22 DEGs in SARS-CoV-2 infected hiPSC-CMs overlapped with the 97 therapeutic targets, which might be the therapeutic targets of Xuebijing injection on COVID-19-induced cardiac dysfunction. Based on the bioinformatics analysis, 7 genes (CCL2, CXCL8, FOS, IFNB1, IL-1A, IL-1B, SERPINE1) were identified as central hub genes and enriched in pathways including cytokines, inflammation, cell senescence and oxidative stress. ACE2, the receptor of SARS-CoV-2, and the 7 central hub genes were differentially expressed in at least two kinds of SARS-CoV-2 infected CMs. Besides, FOS and quercetin exhibited the tightest binding by molecular docking analysis.

CONCLUSION

Our study indicated the underlying protective effect of Xuebijing injection on COVID-19, especially on COVID19-induced cardiac dysfunction, which provided the theoretical basis for exploring the potential protective mechanism of Xuebijing injection on COVID19-induced cardiac dysfunction.

Regulation of miRNAs by Natural Antioxidants in Cardiovascular Diseases: Focus on SIRT1 and eNOS

Cardiovascular diseases (CVDs) are the most common cause of morbidity and mortality worldwide. The potential benefits of natural antioxidants derived from supplemental nutrients against CVDs are well known. Remarkably, natural antioxidants exert cardioprotective effects by reducing oxidative stress, increasing vasodilation, and normalizing endothelial dysfunction. Recently, considerable evidence has highlighted an important role played by the synergistic interaction between endothelial nitric oxide synthase (eNOS) and sirtuin 1 (SIRT1) in the maintenance of endothelial function. To provide a new perspective on the role of natural antioxidants against CVDs, we focused on microRNAs (miRNAs), which are important posttranscriptional modulators in human diseases. Several miRNAs are regulated via the consumption of natural antioxidants and are related to the regulation of oxidative stress by targeting eNOS and/or SIRT1. In this review, we have discussed the specific molecular regulation of eNOS/SIRT1-related endothelial dysfunction and its contribution to CVD pathologies; furthermore, we selected nine different miRNAs that target the expression of eNOS and SIRT1 in CVDs. Additionally, we have summarized the alteration of miRNA expression and regulation of activities of miRNA through natural antioxidant consumption.

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

BACKGROUND

Apigenin can reduce cardiomyocyte hypertrophy by downregulating hypoxia inducible factor-1 alpha (HIF-1α) expression. However, its effects on cardiac fibroblasts (CFs) and its exact inhibitory molecular mechanisms on HIF-1α remain unclear.

PURPOSE

This study aims to examine the effects of apigenin on cell proliferation and differentiation, microRNA-122-5p (miR-122-5p) expression, and HIF-1α-mediated Smad signaling pathway in transforming growth factor beta 1 (TGF-β1)-stimulated CFs and cardiac fibrosis and to investigate the relationship between miR-122-5p and HIF-1α.

METHODS

The TGF-β1-stimulated CFs, the combination of TGF-β1-stimulated and miR-122-5p mimic-transfected CFs, the combination of TGF-β1-stimulated and miR-122-5p inhibitor-transfected CFs, and the isoproterenol-induced cardiac fibrotic mice were used and treated with or without apigenin. The recombinant lentiviruses overexpressing HIF-1α vector and miR-122-5p mimic were co-transfected to observe their interaction. Related mRNA and protein expressions and myocardial collagen were determined. The luciferase reporter gene that contains HIF-1α wild type or mutant type 3'-UTR was used, and the luciferase activity was determined to verify the direct link between miR-122-5p and HIF-1α.

RESULTS

In the TGF-β1-stimulated CFs, apigenin treatment increased the miR-122-5p and Smad7 expressions and decreased the HIF-1α, α-smooth muscle actin, collagen Ⅰ/Ⅲ, Smad2/3, and p-Smad2/3 expressions. Similar and inverse results were observed in the miR-122-5p mimic- and inhibitor-transfected CFs, respectively. Moreover, the miR-122-5p mimic could antagonize the effects of TGF-β1 in the TGF-β1 and miR-122-5p mimic-combined CFs, and the miR-122-5p inhibitor could enhance the effects of TGF-β1 in the TGF-β1 and miR-122-5p inhibitor-combined CFs. In the two aforementioned cell models, the addition of apigenin could further enhance the effects of miR-122-5p mimic and partially reverse the effects of miR-122-5p inhibitor. After treatment of HIF-1α-transfected CFs with miR-122-5p mimic, the HIF-1α expression decreased. Further study confirmed that HIF-1α was a direct target of miR-122-5p. Apigenin also decreased the myocardial collagen accumulation in cardiac fibrotic mice.

CONCLUSION

Apigenin could suppress the differentiation and collagen synthesis of TGF-β1-stimulated CFs and mouse cardiac fibrosis, and its mechanisms were related to the increment of miR-122-5p expression and subsequent downregulation of HIF-1α expression via direct interaction, which might finally result in the decrements of Smad2/3 and p-Smad2/3 expressions and increment of Smad7 expression.

Polyphenols in the Mediterranean Diet: From Dietary Sources to microRNA Modulation

It is now well established that polyphenols are a class of natural substance that offers numerous health benefits; they are present in all plants in very different quantities and types. On the other hand, their bioavailability, and efficacy is are not always well proven. Therefore, this work aims to discuss some types of polyphenols belonging to Mediterranean foods. We chose six polyphenols-(1) Naringenin, (2) Apigenin, (3) Kaempferol, (4) Hesperidin, (5) Ellagic Acid and (6) Oleuropein-present in Mediterranean foods, describing dietary source and their chemistry, as well as their pharmacokinetic profile and their use as nutraceuticals/supplements, in addition to the relevant element of their capability in modulating microRNAs expression profile.

Food Bioactive Compounds and Emerging Techniques for Their Extraction: Polyphenols as a Case Study

Experimental studies have provided convincing evidence that food bioactive compounds (FBCs) have a positive biological impact on human health, exerting protective effects against non-communicable diseases (NCD) including cancer and cardiovascular (CVDs), metabolic, and neurodegenerative disorders (NDDs). These benefits have been associated with the presence of secondary metabolites, namely polyphenols, glucosinolates, carotenoids, terpenoids, alkaloids, saponins, vitamins, and fibres, among others, derived from their antioxidant, antiatherogenic, anti-inflammatory, antimicrobial, antithrombotic, cardioprotective, and vasodilator properties. Polyphenols as one of the most abundant classes of bioactive compounds present in plant-based foods emerge as a promising approach for the development of efficacious preventive agents against NCDs with reduced side effects. The aim of this review is to present comprehensive and deep insights into the potential of polyphenols, from their chemical structure classification and biosynthesis to preventive effects on NCDs, namely cancer, CVDs, and NDDS. The challenge of polyphenols bioavailability and bioaccessibility will be explored in addition to useful industrial and environmental applications. Advanced and emerging extraction techniques will be highlighted and the high-resolution analytical techniques used for FBCs characterization, identification, and quantification will be considered.