Kaempferol protects lipopolysaccharide-induced inflammatory injury in human aortic endothelial cells (HAECs) by regulation of miR-203

Bioactive Compounds in Sea Buckthorn and their Efficacy in Preventing and Treating Metabolic Syndrome

Sea buckthorn (Hippophae rhamnoides L. or Elaeagnus rhamnoides L.) is a plant that has long been used as a Chinese herbal medicine. This species is known to contain numerous bioactive components, including polyphenols, fatty acids, vitamins, and phytosterols, which may be responsible for its medicinal value. In experiments both in vitro and in vivo (ranging from cell lines to animal models and human patients), sea buckthorn has shown positive effects on symptoms of metabolic syndrome; evidence suggests that sea buckthorn treatment can decrease blood lipid content, blood pressure, and blood sugar levels, and regulate key metabolites. This article reviews the main bioactive compounds present in sea buckthorn and discusses their efficacy in treating metabolic syndrome. Specifically, we highlight bioactive compounds isolated from distinct sea buckthorn tissues; their effects on abdominal obesity, hypertension, hyperglycemia, and dyslipidemia; and their potential mechanisms of action in clinical applications. This review provides key insight into the benefits of sea buckthorn, promoting future research of this species and expansion of sea buckthorn-based therapies for metabolic syndrome.

Kaempferol and atherosclerosis: From mechanism to medicine

Natural products possess pleiotropic cardiovascular protective effects owing to their anti-oxidation, anti-inflammation and anti-thrombotic properties. Kaempferol, (3,5,7-trihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one), is a kind of naturally occurring flavonoid existing in many common fruits and vegetables (e.g., onions, broccoli, strawberries and grapes) and particularly in traditional Chinese medicine as exemplified by Ginkgo biloba. Epidemiological, preclinical and clinical studies have revealed an inverse association between the consumption of kaempferol-containing foods and medicines and the risk of developing cardiovascular diseases. Numerous translational studies in experimental animal models and cultured cells have demonstrated a wide range of pharmacological activities of kaempferol. In this article, we reviewed the antioxidant, anti-inflammatory and cardio-protective activities of kaempferol and elucidated the potential molecular basis of the therapeutic capacity of kaempferol by focusing on its anti-atherosclerotic effects. Overall, the review presents the health benefits of kaempferol-containing plants and medicines and reflects on the potential of kaempferol as a possible drug candidate to prevent and treat atherosclerosis, the underlying pathology of most cardiovascular diseases.

Potential mechanisms of Qili Qiangxin capsule to prevent pulmonary arterial hypertension based on network pharmacology analysis in a rat model

Background

Qili Qiangxin capsule (QQC), a traditional Chinese medicine, has recently been approved to treat pulmonary arterial hypertension (PAH). However, the multi-target mechanism through which QQC acts on PAH has not been clarified. The objective of this study was to explore the pharmacological processes of QQC for treating PAH.

Methods

The rat model of PAH was established by administering monocrotaline (MCT). The impact of QQC on PAH was studied in treatment group that received QQC orally over a period of 4 weeks. The Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was searched for active compounds and QQC targets that were then identified and downloaded. Then, PAH-related targets were obtained from five databases [GeneCards, DrugBank, Online Mendelian Inheritance in Man (OMIM), Therapeutic Target Database (TTD), and PharmGKB]. The QQC targets for PAH were compiled after they had been overlapped with one another. Furthermore, the STRING network platform, the Cytoscape tool, networks of protein-protein interaction (PPI) were used, and core target analyses were carried out. Moreover, molecular docking techniques were employed in this research. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment studies of overlapping targets were carried out using the R software (version: 4.0.5; Lucent Technologies Co., Ltd., China). Finally, we verified the synergistic action mechanisms using western blotting and immunofluorescence analysis on PAH rats who were treated with or without QQC.

Results

The search of the TCMSP database showed that there were 11 active ingredients in QQC that treated PAH. PPI network showed that AKT1, TP53, JUN, and MAPK1 were the most important targets in the treatment of PAH. Moreover, Molecular docking techniques showed that the affinity between the bioactive compounds in QQC and their PAH targets was strong. In vivo experiments demonstrated that QQC may attenuate the progression of MCT-stimulated PAH in rats. Furthermore, the protective effect was mediated by inhibiting the PI3K/AKT pathway. The active compounds mainly included quercetin, kaempferol, formononetin, and luteolin, which had good docking scores and targeted the AKT protein.

Conclusions

QQC might activate the PI3K/AKT signaling pathway to ameliorate MCT-induced PAH. These findings support the clinical use of QQC and provide the foundation for further studies.

The bioactivity and applications of pomegranate peel extract: A review

Pomegranate peel (PP) is a by-product in the processing of pomegranate products, which is usually discarded as a waste. However, a large number of researches have shown that pomegranate peel extract (PPE) is rich in a variety of phenolic substances, among which ellagic acid (EA), as one of the main active components, has significant biological activities, such as anti-oxidation, anti-tumor, anti-inflammatory, neuroprotection, anti-viral, and anti-bacterial. We analyzed the mechanism of EA's biological activity, and discussed its application in the food industry, for instance, food preservation, food additives, and functional foods. Combined with the research status of PPE, we discussed the limitations and development potential of PPE, in order to provide theoretical reference and scientific basis for the development and utilization of pomegranate by-products. PRACTICAL APPLICATIONS: Pomegranate peel (PP), the inedible part of the fruit, is usually treated as waste. In recent years, researchers have been committed to exploring various bioactive ingredients in PP and exploring its potential benefits to human health, which has far-reaching significance. In this paper, the chemical constituents of polyphenols in PP were reviewed, mainly focusing on the biological activity and mechanism of ellagic acid (EA). We reviewed the applications and invention patents of pomegranate peel extract (PPE) in food field, including food preservation, food additive, and functional foods, providing reference for the recycling and reuse of PP.

Kaempferol prevents cadmium chloride-induced liver damage by upregulating Nrf2 and suppressing NF-κB and keap1

This study evaluated the protective effect of kaempferol, a natural flavonoid, against cadmium chloride (CdCl₂)-induced liver damage and examined the possible anti-inflammatory and antioxidant mechanisms of protection. Adult male rats were divided into 4 groups (each of 8 rats) as control, kaempferol (50 mg/kg/day orally), CdCl₂ (15 ppm/day), and CdCl₂ (15 ppm/day) + kaempferol (50 mg/kg/day). All treatments were given for 30 days. With no effect on attenuating the reduced food intake, kaempferol significantly increased body weight and lowered serum levels of liver injury markers including bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase 1 (γ-GTT1) in the CdCl₂-treated rats. It also restored normal liver architectures, prevented hepatocyte, loss, and swelling and reduced inflammatory cell infiltration. These effects were associated with a reduction in mitochondrial permeability transition pore, as well as in the expression of cytochrome-c and cleaved caspase-3, markers of mitochondrial damage, and intrinsic cell death. In both the control positive and CdCl₂-treated rats, kaempferol significantly lowered the hepatic levels of reactive oxygen species, malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), Interleukine-6 (IL-6), and the nuclear activity and localization of NF-κB p65. Besides, kaempferol significantly increased the hepatic total and nuclear levels of the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1, as well as levels of superoxide dismutase (SOD) and reduced glutathione (GSH) but reduced the cytoplasmic protein levels of keap1. In conclusion, the protective effect of kaempferol against CdCl₂-induced hepatic damage is mediated by antioxidant and anti-inflammatory effects driven by upregulating Nrf2/HO-1 axis and suppressing the NF-κB p65 and keap1.

TLR4-Myd88 pathway upregulated caveolin-1 expression contributes to coronary artery spasm

AIM

To study the role of toll-like receptors 4-myeloid differentiation factor 88 (TLR4-Myd88) dependent caveolin-1 (Cav-1) expression modulation in coronary artery spasm (CAS) and explore the underlying pathogenic mechanisms.

METHODS AND RESULTS

Lipopolysaccharide (LPS) and acetylcholine (Ach) were used to develop the in vitro and in vivo models mimicking the physiological CAS microenvironment. LPS-induced upregulation of Cav-1 expression in mouse coronary and aorta endothelial cells was shown by western blot and immunofluorescence (IF) staining (p < 0.01). Caveolin-1-knockout (Cav-1^-/-) mice had reduced aortic inflammation after LPS challenge, and fewer ST segment changes were observed through electrocardiogram (ECG) monitoring compared to wild type mice after LPS and ACh administration. In vitro, pretreating human umbilical vein endothelial cells (HUVECs) with siCav-1 to knock down Cav-1 expression reduced the endothelial inflammation following LPS challenge. SiCav-1 also partially reversed the attenuated Ca²⁺ concentration after LPS and ACh administration compared to the control group, which was evaluated by fluorescent molecular probing for Ca²⁺ alternation monitoring (p < 0.05). TLR4 and Myd88 downregulation by siRNA partially blocked the increased Cav-1 mRNA and protein expressions following LPS treatment, as well as partially reversed the decreased NO production evaluated by nitrate reductase method and the impaired Ca²⁺ concentration of endothelial cells induced by LPS and ACh.

CONCLUSION

These findings suggested that Cav-1, which was upregulated by TLR4-Myd88, served as an important modulator of CAS microenvironment establishment in vivo and in vitro, making it a potential pharmacologic target for the treatment of vasospasm via reduced endothelial cell inflammation.

Influence of the Bioactive Diet Components on the Gene Expression Regulation

Diet bioactive components, in the concept of nutrigenetics and nutrigenomics, consist of food constituents, which can transfer information from the external environment and influence gene expression in the cell and thus the function of the whole organism. It is crucial to regard food not only as the source of energy and basic nutriments, crucial for living and organism development, but also as the factor influencing health/disease, biochemical mechanisms, and activation of biochemical pathways. Bioactive components of the diet regulate gene expression through changes in the chromatin structure (including DNA methylation and histone modification), non-coding RNA, activation of transcription factors by signalling cascades, or direct ligand binding to the nuclear receptors. Analysis of interactions between diet components and human genome structure and gene activity is a modern approach that will help to better understand these relations and will allow designing dietary guidances, which can help maintain good health.

Oxidized LDL-regulated microRNAs for evaluating vascular endothelial function: molecular mechanisms and potential biomarker roles in atherosclerosis

As a simple monolayer, vascular endothelial cells can respond to physicochemical stimuli. In addition to promoting the formation of foam cells, oxidized low-density lipoprotein (ox-LDL) contributes to the atherosclerotic process through different mechanisms, including endothelial cell dysfunction. As conserved noncoding RNAs, microRNAs (miRNAs) naturally lie in different genomic positions and post-transcriptionally regulate the expression of many genes. They participate in integrated networks formed under stress to maintain cellular homeostasis, vascular inflammation, and metabolism. These small RNAs constitute therapeutic targets in different diseases, including atherosclerosis, and their role as biomarkers is crucial given their detectability even years before the emergence of diseases. This review was performed to investigate the role of ox-LDL-regulated miRNAs in atherosclerosis, their molecular mechanisms, and their application as biomarkers of vascular endothelial cell dysfunction.

Pharmacological activities and Therapeutic potential of kaempferitrin in medicine for the treatment of human disorders: A review of medicinal importance and health benefits

BACKGROUND

Herbal drugs and their derived phytochemicals are valuable for human being as a source of vital component of food material and drugs. Flavonoids are naturally occurring phytochemical produced in plants through metabolisms and they are having anti-hyperlipidemia, anti-inflammatory, anti-oxidant and anti-apoptotic activity. Flavonoids have been identified in the fruits, nuts, vegetables, seeds, stem, flowers and tea. Kaempferol is a natural flavonoidal compound present in edible plants such as apples, broccoli, strawberries, beans, grapefruit, propolis and medicinal plants such as Aloe vera, Ginkgo biloba, Rosmarinus officinalis, Crocus sativus L., Hypericum perforatum L. Kaempferol have anti-oxidant, anti-inflammatory, anti-apoptotic, pro-apoptotic, cardio-protective and anti-cancer activities.

METHODS

Glycosides of kaempferol such as kaempferitrin also called kaempferol 3,7-dirhamnoside are known to be more abundant than their flavonoid monomers in plants. Various literature databases have been searched to collect all the scientific information of kaempferitrin in the present investigation and analyzed in order to know the therapeutic benefit and biological potential of kaempferitrin. Moreover all the information has been presented here in two broad sections i.e. pharmacological and analytical.

RESULTS

From the analysis of all the collected and presented information, it was found that kaempferitrin has potent insulin-mimetic potential and could be used for the treatment of diabetes and related complication. However, it has also shown anti-oxidant, anti-inflammatory, anti-convulsant, anti-osteoporotic, anti-depressant, anthelmintic, immunostimulatory and natriuretic properties and inhibits cell proliferation and apoptosis. Kaempferitrin also improves meat quality of broiler chickens.

CONCLUSIONS

The presented information in this work will be valuable to justify the biological importance and therapeutic potential of kaempferitrin in the scientific field.

Potential mechanisms of Guizhi decoction against hypertension based on network pharmacology and Dahl salt-sensitive rat model

Background

Guizhi decoction (GZD), a classical Chinese herbal formula, has been widely used to treat hypertension, but its underlying mechanisms remain elusive. The present study aimed to explore the potential mechanisms and therapeutic effects of GZD on hypertension by integrating network pharmacology and experimental validation.

Methods

The active ingredients and corresponding targets were collected from the Traditional Chinese Medicine Systems Pharmacology database and Analysis Platform (TCMSP). The targets related to hypertension were identified from the CTD, GeneCards, OMIM and Drugbank databases. Multiple networks were constructed to identify the key compounds, hub targets, and main biological processes and pathways of GZD against hypertension. The Surflex-Dock software was used to validate the binding affinity between key targets and their corresponding active compounds. The Dahl salt-sensitive rat model was used to evaluate the therapeutic effects of GZD against hypertension.

Results

A total of 112 active ingredients, 222 targets of GZD and 341 hypertension-related targets were obtained. Furthermore, 56 overlapping targets were identified, five of which were determined as the hub targets for experimental verification, including interleukin 6 (IL-6), C–C motif chemokine 2 (CCL2), IL-1β, matrix metalloproteinase 2 (MMP-2), and MMP-9. Pathway enrichment analysis results indicated that 56 overlapping targets were mainly enriched in several inflammation pathways such as the tumor necrosis factor (TNF) signaling pathway, Toll-like receptor (TLR) signaling pathway and nuclear factor kappa-B (NF-κB) signaling pathway. Molecular docking confirmed that most active compounds of GZD could bind tightly to the key targets. Experimental studies revealed that the administration of GZD improved blood pressure, reduced the area of cardiac fibrosis, and inhibited the expression of IL-6, CCL2, IL-1β, MMP-2 and MMP-9 in rats.

Conclusion

The potential mechanisms and therapeutic effects of GZD on hypertension may be attributed to the regulation of cardiac inflammation and fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00446-x.

Flavonoids from sea buckthorn: A review on phytochemistry, pharmacokinetics and role in metabolic diseases

Sea buckthorn (Hippophae rhamnoides L., SBT) is being used as a folk medicine for their diverse medicinal properties. Flavonoids are generally considered as the main bioactive and characteristic ingredients in SBT. This review was conducted using a comprehensive literature search on the chemical components, quality control, pharmacokinetics of flavonoids from SBT (FSBT). Particularly, we highlighted the therapeutic potential in metabolic diseases and clinical applications of FSBT. More than 95 flavonoids have been identified from SBT. Although the oral bioavailability of FSBT was relatively low, FSBT displays significant effect on the regulation of metabolism to ameliorate metabolic disorders and their complications. There is a heightened need to explore the bioactive compounds in SBT and mechanism(s) of action of FSBT in order to fully understand the pathways of their activities. PRACTICAL APPLICATIONS: For years, due to the increasing emergence of metabolic syndrome and diverse functions of FSBT in regulating metabolism, they can be efficiently utilized for human health and have an urgent need to become a hotspot for research. This review will broaden the understanding of FSBT, providing some directions for further development and expanding the therapeutic applications of FSBT.

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.

Link between microbiota and hypertension: Focus on LPS/TLR4 pathway in endothelial dysfunction and vascular inflammation, and therapeutic implication of probiotics

High blood pressure (BP) presents a significant public health challenge. Recent findings suggest that altered microbiota can exert a hypertensive effect on the host. One of the possible mechanisms involved is the chronic translocation of its components, mainly lipopolysaccharides (LPS) into systemic circulation leading to metabolic endotoxemia. In animal models, LPS has been commonly used to induce endothelial dysfunction and vascular inflammation. In human studies, plasma LPS concentration has been positively correlated with hypertension, however, the mechanistic link has not been fully elucidated. It is hypothesised here that the LPS-induced direct alterations to the vascular endothelium and resulting hypertension are possible targets for probiotic intervention. The methodology of this review involved a systematic search of the literature with critical appraisal of papers. Three tranches of search were performed: 1) existing review papers; 2) primary mechanistic animal, in vitro and human studies; and 3) primary intervention studies. A total of 70 peer-reviewed papers were included across the three tranches and critically appraised using SIGN50 for human studies and the ARRIVE guidelines for animal studies. The extracted information was coded into key themes and summarized in a narrative analysis. Results highlight the role of LPS in the activation of endothelial toll-like receptor 4 (TLR4) initiating a cascade of interrelated signalling pathways including: 1) Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase/ Reactive oxygen species (ROS)/ Endothelial nitric oxide synthase (eNOS) pathway leading to endothelial dysfunction; and 2) Mitogen-Activated Protein Kinase (MAPK) and Nuclear factor kappa B (NF-κB) pathways leading to vascular inflammation. Findings from animal intervention studies suggest an improvement in vasorelaxation, vascular inflammation and hypertension following probiotic supplementation, which was mediated by downregulation of LPS-induced pathways. Randomised controlled trials (RCTs) and systematic reviews provided some evidence for the anti-inflammatory effect of probiotics with statistically significant antihypertensive effect in clinical samples and may offer a viable intervention for the management of hypertension.

Nano-soldiers Ameliorate Silibinin Delivery: A Review Study

Flavonoids are a large group of naturally occurring compounds, which are of interest due to their great pharmacological effects and health-promoting impacts. These properties have led to their extensive application in a variety of pathological conditions, particularly cancer. Flavonoids are used in large quantities in a human's daily diet and a high amount of flavonoids are found in the intestine after oral usage. However, flavonoid concentrations in tissue/plasma are low because of their low bioavailability, the leading to the low efficacy of flavonoids in different clinical disorders. For this reason, nanotechnology application for delivering flavonoids to tumor sites has recently received significant attention. Silibinin is a key member of flavonoids and a bioactive component of silymarin, which is widely isolated from Silybum marianum. This plant-derived chemical has a number of valuable biological and therapeutic activities such as antioxidant, anti-inflammatory, neuroprotective, anti-tumor, hepatoprotective, cardioprotective and anti-diabetic. These beneficial effects have been demonstrated in in vivo and in vitro experiments. However, it seems that silibinin has a variety of limitations and poor bioavailability is the most important factor restricting its wide application. Hence, there have been attempts to improve the bioavailability of silibinin and it has been suggested that nano-soldiers are potential candidates for this aim. In the present review, we describe the different drug delivery systems for improving the bioavailability of silibinin.

Knockdown of SLC35F2 Inhibits the Proliferation and Metastasis of Bladder Cancer Cells

Background

Many studies have shown that solute carrier family 35 member F2 (SLC35F2) plays a key role in the biological processes of multiple cancers. However, there have been no reports on the role of SLC35F2 in the occurrence and development of bladder cancer (BC).

Methods

SLC35F2 expression data and clinical and prognostic information from BC patients were obtained from databases. SLC35F2 expression in BC was verified by quantitative real-time PCR (qRT-PCR). The influence of SLC35F2 knockdown on the proliferation, apoptosis, migration and invasion in the 5637 and T24 cell lines was studied, and tumor formation experiments were performed in nude mice. Gene set enrichment analysis (GSEA) was used to predict the pathways and functions of SLC35F2 in BC.

Results

SLC35F2 was highly expressed in BC tissues and was associated with invasiveness and T stage in BC patients. SLC35F2 knockdown can inhibit the proliferation, migration and invasion of BC cells and can promote apoptosis. SLC35F2 knockdown significantly reduced tumorigenesis in nude mice. GSEA showed that BC, pathways in cancer, apoptosis and the P53 signaling pathway were significantly enriched in SLC35F2 high expression phenotype.

Conclusion

SLC35F2 can promote malignant progression and is a potential therapeutic target in BC.

Evaluating the biochemical changes of LPS-stimulated endothelial cells by synchrotron FTIR microspectroscopy at a single-cell level

Endothelial damage is a major manifestation in many forms of heart and lung injuries induced by lipopolysaccharide (LPS), but the biochemical responses and activation mechanisms of endothelial cells have not been fully explicit. In this study, the biochemical changes to endothelial cells exposed to LPS were investigated by synchrotron FTIR microspectroscopy at a single-cell level. We found that the whole infrared spectrum of endothelial cells shifted after LPS treatment, indicating chemical component changes within cells. Principal component analysis (PCA) and t tests on subspectra (fatty acid region, protein region, and nucleic acid-sugar region, respectively) further showed that sugar components as well as fatty acids changed dramatically while proteins had no significant variation following LPS exposure. These results suggested that the glycocalyx layer structure on endothelial cell membrane may be mainly influenced by LPS and also proved that synchrotron FTIR microspectroscopy was a useful technique to evaluate the biochemical changes of endothelial damage at the single-cell level. Graphical abstract.

Impact of deoxynivalenol and kaempferol on expression of tight junction proteins at different stages of Caco-2 cell proliferation and differentiation

The expression of tight junction proteins in human epithelial colorectal adenocarcinoma (Caco-2) cells was investigated after treatment by the mycotoxin of deoxynivalenol and phenolic compound of kaempferol in different stages of proliferation and differentiation.