Procyanidin B2 alleviates oxidized low-density lipoprotein-induced cell injury, inflammation, monocyte chemotaxis, and oxidative stress by inhibiting the nuclear factor kappa-B pathway in human umbilical vein endothelial cells.

BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) can initiate and affect almost all atherosclerotic events including endothelial dysfunction. In this text, the role and underlying molecular basis of procyanidin B2 (PCB2) with potential anti-oxidant and anti-inflammatory activities in ox-LDL-induced HUVEC injury were examined. METHODS: HUVECs were treated with ox-LDL in the presence or absence of PCB2. Cell viability and apoptotic rate were examined by CCK-8 assay and flow cytometry, respectively. The mRNA and protein levels of genes were tested by RT-qPCR and western blot assays, respectively. Potential downstream targets and pathways of apple procyanidin oligomers were examined by bioinformatics analysis for the GSE9647 dataset. The effect of PCB2 on THP-1 cell migration was examined by recruitment assay. The effect of PCB2 on oxidative stress was assessed by reactive oxygen species (ROS) level, malondialdehyde (MDA) content, and mitochondrial membrane potential (MMP). RESULTS: ox-LDL reduced cell viability, induced cell apoptosis, and facilitated the expression of oxidized low-density lipoprotein receptor 1 (LOX-1), C-C motif chemokine ligand 2 (MCP-1), vascular cell adhesion protein 1 (VCAM-1) in HUVECs. PCB2 alleviated ox-LDL-induced cell injury in HUVECs. Apple procyanidin oligomers triggered the differential expression of 592 genes in HUVECs (|log2fold-change| > 0.58 and adjusted p-value < 0.05). These dysregulated genes might be implicated in apoptosis, endothelial cell proliferation, inflammation, and monocyte chemotaxis. PCB2 inhibited C-X-C motif chemokine ligand 1/8 (CXCL1/8) expression and THP-1 cell recruitment in ox-LDL-stimulated HUVECs. PCB2 inhibited ox-LDL-induced oxidative stress and nuclear factor kappa-B (NF-κB) activation in HUVECs. CONCLUSION: PCB2 weakened ox-LDL-induced cell injury, inflammation, monocyte recruitment, and oxidative stress by inhibiting the NF-κB pathway in HUVECs.

Experience-Dependent Behavioral Plasticity in Avoiding Epigallocatechin Gallate (EGCG) Requires DAF-16/FOXO in the AIY Interneurons of Caenorhabditis elegans.

Bitterness and astringency are the aversive tastes in mammals. In humans, aversion to bitterness and astringency may be reduced depending on the eating experience. However, the cellular and molecular mechanisms underlying plasticity in preference to bitter and astringent tastants remain unknown. This study aimed to investigate the preference plasticity to bitter and astringent tea polyphenols, including catechins and tannic acids, in the model animal Caenorhabditis elegans. C. elegans showed avoidance behavior against epigallocatechin gallate (EGCG), tannic acid, and theaflavin. However, they displayed diminishing avoidance against EGCG depending on their EGCG-feeding regime at larval stages. Additionally, the behavioral plasticity in avoiding EGCG required the transcription factor DAF-16/FOXO. Isoform-specific deletion mutant analysis and cell-specific rescue analysis revealed that the function of daf-16 isoform b in AIY interneurons is necessary for experience-dependent behavioral plasticity to EGCG.

Senolytic and senomorphic agent procyanidin C1 alleviates structural and functional decline in the aged retina.

Increased cellular senescence burden contributes in part to age-related organ dysfunction and pathologies. In our study, using mouse models of natural aging, we observed structural and functional decline in the aged retina, which was accompanied by the accumulation of senescent cells and senescence-associated secretory phenotype factors. We further validated the senolytic and senomorphic properties of procyanidin C1 (PCC1) both in vitro and in vivo, the long-term treatment of which ameliorated age-related retinal impairment. Through high-throughput single-cell RNA sequencing (scRNA-seq), we comprehensively characterized the retinal landscape after PCC1 administration and deciphered the molecular basis underlying the senescence burden increment and elimination. By exploring the scRNA-seq database of age-related retinal disorders, we revealed the role of cellular senescence and the therapeutic potential of PCC1 in these pathologies. Overall, these results indicate the therapeutic effects of PCC1 on the aged retina and its potential use for treating age-related retinal disorders.

Anti-inflammatory effects of the Thai herbal remedy Yataprasen and biflavonoids isolated from Putranjiva roxburghii in RAW264.7 macrophages.

ETHNOPHARMACOLOGICAL RELEVANCE: Yataprasen is a topical Thai herbal remedy for the treatment of musculoskeletal pain and is included in Kumpe Thart Phra Narai, the first Thai textbook of traditional medicine. The herbal preparation is made from a hydroethanolic extract of a mixture of 13 medicinal plants, of which Putranjiva roxburghii Wall. leaves are the major ingredient. AIM OF THE STUDY: In this study, we investigated the underlying mechanism of action for the anti-inflammatory effects of the Yataprasen remedy, its main ingredients, and the phytochemicals isolated from P. roxburghii leaves. MATERIALS AND METHODS: The anti-inflammatory effects of the Yataprasen remedy, along with its main ingredients, including the leaves of Baliospermum solanifolium (Burm.) Suresh, Melia azedarach L., P. roxburghii, Senna siamea (Lam.) Irwin & Barneby, and Tamarindus indica L. were determined by measuring prostaglandin E2 (PGE2) secretion, nitric oxide (NO) production, and the synthesis of inflammatory biomarkers in lipopolysaccharide (LPS)-treated RAW264.7 macrophage cells. The active ingredients of the P. roxburghii leaves were separated by chromatography and spectroscopic measurements were used to identify their chemical structures. RESULTS: Ethanol extracts of the Yataprasen remedy and some of its ingredients significantly suppressed LPS-induced PGE2 secretion and NO production in a dose-dependent manner. Treatment of RAW264.7 cells with ethanolic extracts of the Yataprasen remedy (50 µg/mL) significantly inhibited LPS-induced mRNA expression of TNF-α, COX-2, iNOS, and NF-κB. Among the plant ingredient extracts, P. roxburghii leaf extract exhibited the highest inhibitory effects on LPS-induced TNF-α and iNOS expression. Moreover, T. indica leaf extract showed the highest activity on the inhibition of LPS-induced COX-2 and NF-κB expression. Putraflavone, podocarpusflavone A, and amentoflavone were isolated biflavonoids from P. roxburghii leaf extract and showed the inhibitory effects on LPS-induced PGE2 secretion and NO synthesis in RAW264.7 cells. Of the isolated biflavonoids, amentoflavone exhibited the strongest anti-inflammatory activity by inhibiting the expression of TNF-α, COX-2, and iNOS. CONCLUSION: The results support reported the anti-inflammatory effects of the Yataprasen remedy, which are associated with the downregulation of proinflammatory mediators. P. roxburghii, along with its biflavonoids, are the impact components that contribute to the anti-inflammatory effects of the herbal remedy.

The Phytochemical Agathisflavone Modulates miR146a and miR155 in Activated Microglia Involving STAT3 Signaling.

MicroRNAs (miRs) act as important post-transcriptional regulators of gene expression in glial cells and have been shown to be involved in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). Here, we investigated the effects of agathisflavone, a biflavonoid purified from the leaves of Cenostigma pyramidale (Tul.), on modulating the expression of miRs and inflammatory mediators in activated microglia. C20 human microglia were exposed to oligomers of the ß-amyloid peptide (Aß, 500 nM) for 4 h or to lipopolysaccharide (LPS, 1 µg/mL) for 24 h and then treated or not with agathisflavone (1 µM) for 24 h. We observed that ß-amyloid and LPS activated microglia to an inflammatory state, with increased expression of miR-146a, miR-155, IL1-ß, IL-6, and NOS2. Treatment with agathisflavone resulted in a significant reduction in miR146a and miR-155 induced by LPS or Aß, as well as inflammatory cytokines IL1-ß, IL-6, and NOS2. In cells stimulated with Aß, there was an increase in p-STAT3 expression that was reduced by agathisflavone treatment. These data identify a role for miRs in the anti-inflammatory effect of agathisflavone on microglia in models of neuroinflammation and AD.

Effects of grape seed procyanidins on the lipid metabolism of growing-finishing pigs based on transcriptomics and metabolomics analyses.

This study investigated how lipid metabolism in the longissimus thoracis is influenced by the diet supplemented with grape seed procyanidins (GSPs) in growing-finishing pigs. Forty-eight crossbred pigs were randomly assigned to four groups, each receiving a basal diet, or basal diet added with 150, 200, and 250 mg/kg GSPs. Transcriptomics and metabolomics were employed to explore differential gene and metabolite regulation. The expression of key lipid metabolism-related genes was tested via qRT-PCR, and the lipid and fatty acid composition of the longissimus thoracis were determined. Dietary GSPs at different concentrations upregulated lipoprotein lipase (LPL), which is involved in lipolysis, and significantly increased the mRNA expression levels of carnitine palmitoyltransferase-1B (CPT1B) and cluster of differentiation 36 (CD36), implicated in transmembrane transport of fatty acids. Dietary supplementation of GSPs at 200 or 250 mg/kg markedly reduced total cholesterol and triglyceride content in longissimus thoracis. Dietary GSPs significantly decreased the contents of low-density lipoprotein cholesterol and saturated fatty acids, while increasing unsaturated fatty acids. In conclusion, GSPs may regulate lipid metabolism, reducing cholesterol level, and improving fatty acid composition in the longissimus thoracis of growing-finishing pigs. Our findings provide evidence for the beneficial effects of GSPs as pig feed additives for improving lipid composition.

Novel l-Cysteine Incomplete Degradation Method for Preparation of Procyanidin B2-3'-O-Gallate and Exploration of its in Vitro Anti-inflammatory Activity and in Vivo Tissue Distribution.

In this study, an effective method for preparation of bioactive galloylated procyanidin B2-3'-O-gallate (B2-3'-G) was first developed by incomplete depolymerization of grape seed polymeric procyanidins (PPCs) using l-cysteine (Cys) in the presence of citric acid. The structure-activity relationship of B2-3'-G was further evaluated in vitro through establishing lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells. The results suggested that the better protective effects of B2-3'-G against inflammation were attributed to its polymerization degree and the introduction of the galloyl group, compared to its four corresponding structural units. In vivo experiments demonstrated that the B2-3'-G prototype was distributed in plasma, small intestine, liver, lung, and brain. Remarkably, B2-3'-G was able to penetrate the blood-brain barrier and appeared to play an important role in improving brain health. Furthermore, a total of 18 metabolites were identified in tissues. Potential metabolic pathways, including reduction, methylation, hydration, desaturation, glucuronide conjugation, and sulfation, were suggested.

Pharmacotherapeutic potential of ginkgetin against polystyrene microplastics-instigated testicular toxicity in rats: A biochemical, spermatological, and histopathological assessment.

Polystyrene microplastics (PSMPs) have emerged as a ubiquitous environmental toxicant that affects different organs including testes. Ginkgetin (GNG) is a biflavonoid that shows antioxidant properties. The current research was undertaken to evaluate the ameliorative potential of GNG against PSMPs-instigated testicular damages. Forty-eight albino rats (male) were randomly divided into 4 equal groups: control, PSMPs-treated group (0.01 mgkg-1), GNG + PSMPs-exposed group (25 mgkg-1 + 0.01 mgkg-1), and only GNG-supplemented group (25 mgkg-1). After 56 days of treatment, it was revealed that PSMPs significantly reduced the activity of glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GSR), while concurrently augmented the levels of lipid peroxidation marker, i.e., malondialdehyde (MDA) along with reactive oxygen species (ROS). Rats administered with PSMPs showed a significant reduction in the spermatogenic indices (sperm count, viability, and motility), HOS coiled tail sperm along with increased sperm structural deformities, i.e., tail, head, and mid-piece. Additionally, PSMPs exposure decreased the levels of testosterone, luteinizing (LH), and follicle-stimulating hormones (FSH). Besides, administration of PSMPs reduced the steroidogenic enzymes (13ß-HSD, StAR, and 17ß-HSD) and Bcl-2 expression, while augmented the caspase-3 and Bax expression. PSMPs also elevated the levels of inflammatory markers (IL-6, IL-1ß, TNF-α, and NF-κB) and activity of COX-2 in the testes. Furthermore, PSMPs treatment induced various histopathological damages in the testes of rats. Therefore, findings of the current study suggested that GNG effectively mitigated the PSMPs-induced testicular toxicity owing to its chemoprotective potential possibly through its anti-inflammatory, antioxidant, anti-apoptotic, and androgenic properties.

Five new biflavonoids with acetylcholinesterase inhibitory activity from Diphylleia sinensis.

Five new biflavonoids, diphybiflavonoids A - E (1-5), were isolated from the roots and rhizomes of Diphylleia sinensis. Their structures were elucidated by extensive spectroscopic data, including UV, IR, HR-ESI-MS and 2D NMR. Their absolute configurations were determined by ECD spectra. All isolated compounds were evaluated for acetylcholinesterase (AChE) inhibitory activity. Compounds 1-4 exhibited the potent AChE inhibitory activities with IC50 values of 1.62, 2.10, 2.08, and 5.15 µM, respectively. The preliminary structure-activity relationship study indicated that the connection mode (C2-O-C4'''/C3-O-C3''' or C2-O-C3'''/C3-O-C4''') of biflavonoid subunits, and 3-hydroxy group of flavonol subunit were important structural factors for AChE inhibitory activity. Biflavonoids, containing a C2-O-C4'''/C3-O-C3''' or C2-O-C3'''/C3-O-C4''' linkage, can be a potentially useful platform for development of cholinesterase inhibitors.

The Antiobesity Effects and Potential Mechanisms of Theaflavins.

Theaflavins are the characteristic polyphenols in black tea which can be enzymatically synthesized. In this review, the effects and molecular mechanisms of theaflavins on obesity and its comorbidities, including dyslipidemia, insulin resistance, hepatic steatosis, and atherosclerosis, were summarized. Theaflavins ameliorate obesity potentially via reducing food intake, inhibiting pancreatic lipase to reduce lipid absorption, activating the adenosine monophosphate-activated protein kinase (AMPK), and regulating the gut microbiota. As to the comorbidities, theaflavins ameliorate hypercholesterolemia by inhibiting micelle formation to reduce cholesterol absorption. Theaflavins improve insulin sensitivity by increasing the signaling of protein kinase B, eliminating glucose toxicity, and inhibiting inflammation. Theaflavins ameliorate hepatic steatosis via activating AMPK. Theaflavins reduce atherosclerosis by upregulating nuclear factor erythropoietin-2-related factor 2 signaling and inhibiting plasminogen activator inhibitor 1. In randomized controlled trails, black tea extracts containing theaflavins reduced body weight in overweight people and improved glucose tolerance in healthy adults. The amelioration on the hyperlipidemia and the prevention of coronary artery disease by black tea extracts were supported by meta-analysis.

Inhibitory effects against SARSCoV-2 main protease (Mpro) of biflavonoids and benzophenones from the fruit of Platonia insignis.

The SARS-CoV-2 mutation and the limitation of the approved drug against COVID-19 are still a challenge in many country healthcare systems and need to be affronted despite the set of vaccines to prevent this viral infection. To contribute to the identification of new antiviral agents, the present study focused on natural products from an edible fruit with potential inhibitory effects against the SARS-CoV-2 main protease (Mpro). First, LC-ESIMS analysis of Platonia insignis fruits was performed and showed the presence of biflavonoids and benzophenones in the seed and pulp, respectively. Then, maceration and chromatographic purification led to the identification of two triglycerides (1 and 2) alongside chamaejasmine (3) and volkensiflavone (4) from the seed and isogarcinol (5) and cycloxanthochymol (6), from the pulp. Compounds 1-6 after evaluating their inhibitory against Mpro, displayed from no to significant activity. Compound 5 was the most potent with an IC50 value of 0.72 µM and was more active than the positive control, Ebselen (IC50 of 3.4 µM). It displayed weak and no cytotoxicity against THP-1 (CC50 of 116.2 µM) and Vero cell lines, respectively. Other active compounds showed no cytotoxicity against THP-1. and Vero cell lines. Molecular docking studies revealed interactions in the catalytic pocket between compound 5 and amino acid residues that composed the catalytic dyads (His 41 and Cyst 145).

Exploring the inhibitory properties of biflavonoids on α-glucosidase; computational and experimental approaches.

Biflavonoids (BFs) are a group of polyphenols that have a unique biochemical structure. One of the key biomedical mechanisms that BFs can have high potential in managing Diabetes mellitus (DM) is α-glucosidase inhibition. Normally, elevated blood glucose levels are caused by high absorption of glucose in the epithelium of the small intestine. Since α-glucosidase helps increase the absorption of glucose in the small intestine in the final stage of glycan catabolism, inhibition of this essential biochemical process in diabetic patients can be considered a suitable approach in the treatment of this disease. The interaction between the BFs and α-glucosidase are still not clear, and need to be deeply investigated. Herein, the aim is to identify BFs with strong α-glucosidase inhibitory activity. Using docking-based virtual screening approach, the potential binding affinity of 18 selected BFs to α-glucosidase was evaluated. The dynamic activity and stability of α-glucosidase-BFs complexes were then measured by molecular dynamics simulation (MDs). "Strychnobiflavone" showed the best score in α-glucosidase inhibition. Arg315 and Phe303 involved in the interactions of α-glucosidase-strychnobiflavone complex through cation-π and π-π stacking, respectively. Based on in vitro kinetic studies, it was determined that the type of inhibition of "strychnobiflavone" corresponds to the pattern of mixed inhibitors. Furthermore, details of the interactions between strychnobiflavone and α-glucosidase were performed by in silico secondary structure content analysis. The findings showed when "strychnobifone" binds to the enzyme, significant alterations occur in the enzyme conformation affecting its catalytic activity. In general, the findings highlighted the potential of "strychnobiflavone" as a promising candidate for the treatment of diabetes mellitus through α-glucosidase inhibition. Further in vitro and in vivo studies have to confirm the therapeutic benefits of "strychnobiflavone" in conformational diseases such as diabetes mellitus.

The inhibitory effect and mechanism of theaflavins on fluoride transport and uptake in HIEC-6 cell model.

Fluoride (F-) is widely present in nature, while long-term excessive F- intake can lead to fluorosis. Theaflavins are an important bioactive ingredient of black and dark tea, and black and dark tea water extracts showed a significantly lower F- bioavailability than NaF solutions in previous studies. In this study, the effect and mechanism of four theaflavins (theaflavin, theaflavin-3-gallate, theaflavin-3'-gallate, theaflavin-3,3'-digallate) on F- bioavailability were investigated using normal human small intestinal epithelial cells (HIEC-6) as a model. The results showed that theaflavins could inhibit the absorptive (apical - basolateral) transport of F- while promote its secretory (basolateral - apical) transport in HIEC-6 cell monolayers in a time- and concentration-dependent (5-100 µg/mL) manner, and significantly reduce the cellular F- uptake. Moreover, the HIEC-6 cells treated with theaflavins showed a reduction in cell membrane fluidity and cell surface microvilli. Transcriptome, qRT-PCR and Western blot analysis revealed that theaflavin-3-gallate (TF3G) addition could significantly enhance the mRNA and protein expression levels of tight junction-related genes in HIEC-6 cells, such as claudin-1, occludin and zonula occludens-1 (ZO-1). Overall, theaflavins may reduce F- absorptive transport by regulating tight junction-related proteins, and decreasing intracellular F- accumulation by affecting the cell membrane structure and properties in HIEC-6 cells.

Amentoflavone attenuates cell proliferation and induces ferroptosis in human gastric cancer by miR-496/ATF2 axis.

Amentoflavone (AF) is a natural multifunctional biflavonoid that has been revealed to possess multiple biological activities, including anticancer activity. Here, this work focused on exploring the functions and mechanism of AF in gastric cancer (GC). Levels of genes and proteins were examined by quantitative real-time PCR and western blotting. Cell proliferation and cell death were analyzed using cell counting kit-8, colony formation, and lactate dehydrogenase (LDH) release assay, respectively. Cell ferroptosis was evaluated by detecting the levels of malondialdehyde (MDA), reduced glutathione (GSH), Fe2+ , and intracellular reactive oxygen species (ROS). The binding between miR-496 and activating transcription factor 2 (ATF2) was confirmed by using dual-luciferase reporter assay. Murine xenograft assay was conducted for in vivo experiments. The results showed that AF suppressed the proliferation and induced ferroptotic cell death in GC cells. MiR-496 expression was decreased in GC tissues and cells, and AF treatment increased miR-496 expression level in GC cells. Functionally, miR-496 inhibition reversed the inhibitory effects of AF on GC cell proliferation and promoting effects on ferroptotic cell death. Mechanistically, ATF2 was targeted by miR-496. ATF2 expression was increased in GC tissues and cells, which was decreased by AF treatment and subsequently rescued by miR-496 downregulation in GC cells. Moreover, miR-496 overexpression suppressed the proliferation and induced ferroptotic cell death in GC cells via targeting ATF2. In all, AF suppressed the proliferation and induced ferroptotic cell death in GC cells via miR-496/ATF2 axis, indicating a novel therapeutic approach for GC patients.

GB1a Activates SIRT6 to Regulate Lipid Metabolism in Mouse Primary Hepatocytes.

Lipid accumulation, oxidative stress, and inflammation in hepatocytes are features of nonalcoholic fatty liver disease (NAFLD). Garcinia biflavonoid 1a (GB1a) is a natural product capable of hepatic protection. In this study, the effect of GB1a on anti-inflammatory, antioxidant, and regulation of the accumulation in HepG2 cells and mouse primary hepatocytes (MPHs) was investigated, and its regulatory mechanism was further explored. The result showed that GB1a reduced triglyceride (TG) content and lipid accumulation by regulating the expression of SREBP-1c and PPARα; GB1a reduced reactive oxygen species (ROS) and improved cellular oxidative stress to protect mitochondrial morphology by regulating genes Nrf2, HO-1, NQO1, and Keap1; and GB1a reduced the damage of hepatocytes by inhibiting the expression of inflammatory cytokines interleukin-6 (IL-6), interleukin-1ß (IL-1ß), tumor necrosis factor-alpha (TNF-α), and nuclear factor kappa B (NF-κB) p65. The activities of GB1a were lost in liver SIRT6-specific knockout mouse primary hepatocytes (SIRT6-LKO MPHs). This indicated that activating SIRT6 was critical for GB1a to perform its activity, and GB1a acted as an agonist of SIRT6. It was speculated that GB1a may be a potential drug for NAFLD treatment.

The potential beneficial role of Ginkgetin in doxorubicin-induced hepatotoxicity: Elucidating the underlying claim.

Doxorubicin (DOX) is a widely used chemotherapeutic agent for various tumors treatment; apart from its chemotherapeutic activity, the traditional usage of DOX has been limited by its adverse effects on multiple organs, mainly hepatotoxicity. The molecular mechanisms underlying DOX hepatotoxicity are mainly due to the production of reactive oxygen species (ROS) inducing oxidative stress, diminishing antioxidant enzymes, apoptosis, inflammation, and mitochondrial dysfunction. Thus, there is an urgent need to develop a therapy that minimizes DOX hepatotoxicity and widens its use in various types of cancers without fear of its serious hepatotoxicity. Ginkgetin (GINK), a natural biflavonoid, exhibits diverse actions, including promising free radical scavenging, antioxidant, and anti-inflammatory activities. So, this study's objectives were to determine whether GINK could mitigate DOX's hepatotoxic effects and look into a putative hepatoprotective molecular pathway. Mice were divided into five groups: Normal control, control GINK 100, Untreated DOX group, and DOX groups treated with GINK (50 and 100 mg/kg) intraperitoneally daily for four days before DOX administration and an additional three days afterward. GINK 100 pretreatment showed marked protection from DOX hepatotoxicity and also attenuation of histopathological structural alterations. These outcomes were corroborated biochemically by a considerable decrease in alanine aminotransferases, aspartate aminotransferase, and alkaline phosphatase levels. GINK significantly augmented silent information regulator 1 and nuclear translocation of NF-E2-related factor 2 and repressed the expression and protein levels of forkhead box protein O1, inducible nitric oxide synthase, and P53 relative to DOX group. GINK alleviated oxidative stress and induced significant anti-inflammatory effects via suppression of interleukin-6, nuclear factor Kabba B, and iNOS respectively. This study is the first to investigate GINK's potentially beneficial effects in acute DOX hepatotoxicity, possibly exhibiting antioxidant, anti-inflammatory, and anti-apoptotic effects by modulation of Sirt1/FOXO-1/NF-κB Signal.

Total biflavonoids extraction from Selaginella chaetoloma utilizing ultrasound-assisted deep eutectic solvent: Optimization of conditions, extraction mechanism, and biological activity in vitro.

In this study, the deep eutectic solvent based ultrasound-assisted extraction (DES-UAE) was investigated for the efficient and environmentally friendly extraction of Selaginella chaetoloma total biflavonoids (SCTB). As an extractant for optimization, tetrapropylaminium bromide-1,4-butanediol (Tpr-But) was employed for the first time. 36 DESs were created, with Tpr-But producing the most effective results. Based on response surface methodology (RSM), the greatest extraction rate of SCTB was determined to be 21.68 ± 0.78 mg/g, the molar ratio of HBD to HBA was 3.70:1, the extraction temperature was 57 °C, and the water content of DES was 22 %. In accordance with Fick's second rule, a kinetic model for the extraction of SCTB by DES-UAE has been derived. With correlation coefficients 0.91, the kinetic model of the extraction process was significantly correlated with the general and exponential equations of kinetics, and some important kinetic parameters such as rate constants, energy of activation and raffinate rate were determined. In addition, molecular dynamics simulations were used to study the extraction mechanisms generated by different solvents. Comparing the effect of several extraction methods on S.chaetoloma using ultrasound-assisted extraction and conventional methods, together with SEM examination, revealed that DES-UAE not only saved time but also enhanced SCTB extraction rate by 1.5-3 folds. SCTB demonstrated superior antioxidant activity in three studies in vitro. Furthermore, the extract could suppress the growth of A549, HCT-116, HepG2, and HT-29 cancer cells. Alpha-Glucosidase (AG) inhibition experiment and molecular docking studies suggested that SCTB exhibited strong inhibitory activity against AG and potential hypoglycemic effects. The results of this study indicated that a Tpr-But-based UAE method was suitable for the efficient and environmentally friendly extraction of SCTB, and also shed light on the mechanisms responsible for the increased extraction efficiency, which could aid in the application of S.chaetoloma and provide insight into the extraction mechanism of DES.

Ginkgetin suppresses ovarian cancer growth through inhibition of JAK2/STAT3 and MAPKs signaling pathways.

BACKGROUND: Ginkgo biloba L., a kind of traditional Chinese medicine, is always used to treat various diseases. Ginkgetin is an active biflavonoid isolated from leaves of Ginkgo biloba L., which exhibits diverse biological activities, including anti-tumor, anti-microbial, anti-cardiovascular and cerebrovascular diseases, and anti-inflammatory effects. However, there are few reports on the effects of ginkgetin on ovarian cancer (OC). HYPOTHESIS/PURPOSE: OC is one of the most common cancers with high mortality in women. The purpose of this study was to find out how ginkgetin inhibited OC and which signal transduction pathways was involved to suppress OC. METHODS: The OC cell lines, A2780, SK-OV-3 and CP70, were used for in vitro experiments. MTT assay, colony formation, apoptosis assay, scratch wound assay and cell invasion assay were used to determine the inhibitory effect of ginkgetin. BALB/c nude female mice were injected with A2780 cells subcutaneously, then treated with ginkgetin by intragastric administration. Western blot experiment was used to verify the inhibitory mechanism of OC in vitro and in vivo. RESULTS: We found that ginkgetin inhibited the proliferation and induced apoptosis in OC cells. In addition, ginkgetin reduced migration and invasion of OC cells. In vivo study showed that ginkgetin significantly reduced tumor volume in the xenograft mouse model. Furthermore, the anti-tumor effects of ginkgetin were associated with a down regulation of p-STAT3, p-ERK and SIRT1 both in vitro and in vivo. CONCLUSION: Our results suggest that ginkgetin exhibits anti-tumor activity in OC cells via inhibiting the JAK2/STAT3 and MAPK pathways and SIRT1 protein. Ginkgetin could be a potential candidate for the treatment of OC.

Advances in the Anti-Tumor Activity of Biflavonoids in Selaginella.

Despite the many strategies employed to slow the spread of cancer, the development of new anti-tumor drugs and the minimization of side effects have been major research hotspots in the anti-tumor field. Natural drugs are a huge treasure trove of drug development, and they have been widely used in the clinic as anti-tumor drugs. Selaginella species in the family Selaginellaceae are widely distributed worldwide, and they have been well-documented in clinical practice for the prevention and treatment of cancer. Biflavonoids are the main active ingredients in Selaginella, and they have good biological and anti-tumor activities, which warrant extensive research. The promise of biflavonoids from Selaginella (SFB) in the field of cancer therapy is being realized thanks to new research that offers insights into the multi-targeting therapeutic mechanisms and key signaling pathways. The pharmacological effects of SFB against various cancers in vitro and in vivo are reviewed in this review. In addition, the types and characteristics of biflavonoid structures are described in detail; we also provide a brief summary of the efforts to develop drug delivery systems or combinations to enhance the bioavailability of SFB monomers. In conclusion, SFB species have great potential to be developed as adjuvant or even primary therapeutic agents for cancer, with promising applications.

Theaflavin Ameliorates Streptococcus suis-Induced Infection In Vitro and In Vivo.

Streptococcus suis (S. suis) is one of the most important zoonotic pathogens that threaten the lives of pigs and humans. Even worse, the increasingly severe antimicrobial resistance in S. suis is becoming a global issue. Therefore, there is an urgent need to discover novel antibacterial alternatives for the treatment of S. suis infection. In this study, we investigated theaflavin (TF1), a benzoaphenone compound extracted from black tea, as a potential phytochemical compound against S. suis. TF1 at MIC showed significant inhibitory effects on S. suis growth, hemolytic activity, and biofilm formation, and caused damage to S. suis cells in vitro. TF1 had no cytotoxicity and decreased adherent activity of S. suis to the epithelial cell Nptr. Furthermore, TF1 not only improved the survival rate of S. suis-infected mice but also reduced the bacterial load and the production of IL-6 and TNF-α. A hemolysis test revealed the direct interaction between TF1 and Sly, while molecular docking showed TF1 had a good binding activity with the Glu198, Lys190, Asp111, and Ser374 of Sly. Moreover, virulence-related genes were downregulated in the TF1-treated group. Collectively, our findings suggested that TF1 can be used as a potential inhibitor for treating S. suis infection in view of its antibacterial and antihemolytic activity.