The impact of diabetes mellitus on blood-tissue barrier regulation and vascular complications: Is the lung different from other organs?

Diabetes Mellitus presents a formidable challenge as one of the most prevalent and complex chronic diseases, exerting significant strain on both patients and the world economy. It is recognized as a common comorbidity among severely ill individuals, often leading to a myriad of micro- and macro-vascular complications. Despite extensive research dissecting the pathophysiology and molecular mechanisms underlying vascular complications of diabetes, relatively little attention has been paid to potential lung-related complications. This review aims to illuminate the impact of diabetes on prevalent respiratory diseases, including chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), idiopathic pulmonary fibrosis (IPF), tuberculosis (TB), pneumonia infections, and asthma, and compare the vascular complications with other vascular beds. Additionally, we explore the primary mechanistic pathways contributing to these complications, such as the expression modulation of blood-tissue-barrier proteins, resulting in increased paracellular and transcellular permeability, and compromised immune responses rendering diabetes patients more susceptible to infections. The activation of inflammatory pathways leading to cellular injury and hastening the onset of these respiratory complications is also discussed.

Common mechanisms underlying diabetic vascular complications: focus on the interaction of metabolic disorders, immuno-inflammation, and endothelial dysfunction

Diabetic vascular complications (DVCs), including macro- and micro- angiopathy, account for a high percentage of mortality in patients with diabetes mellitus (DM). Endothelial dysfunction is the initial and role step for the pathogenesis of DVCs. Hyperglycemia and lipid metabolism disorders contribute to endothelial dysfunction via direct injury of metabolism products, crosstalk between immunity and inflammation, as well as related interaction network. Although physiological and phenotypic differences support their specified changes in different targeted organs, there are still several common mechanisms underlying DVCs. Also, inhibitors of these common mechanisms may decrease the incidence of DVCs effectively. Thus, this review may provide new insights into the possible measures for the secondary prevention of DM. And we discussed the current limitations of those present preventive measures in DVCs research. Video Abstract.

Natural flavonoids derived from herbal medicines are potential anti-atherogenic agents by inhibiting oxidative stress in endothelial cells

As the common pathological basis of various cardiovascular diseases, the morbidity and mortality of atherosclerosis (AS) have increased in recent years. Unfortunately, there are still many problems in the treatment of AS, and the prevention and treatment of the disease is not ideal. Up to now, the occurrence and development of AS can roughly include endothelial cell dysfunction, vascular smooth muscle cell proliferation, inflammation, foam cell production, and neoangiogenesis. Among them, endothelial dysfunction, as an early event of AS, plays a particularly important role in promoting the development of AS. In addition, oxidative stress occurs throughout the causes of endothelial dysfunction. Some previous studies have shown that flavonoids derived from herbal medicines are typical secondary metabolites. Due to its structural presence of multiple active hydroxyl groups, it is able to exert antioxidant activity in diseases. Therefore, in this review, we will search PubMed, Web of Science, Elesvier, Wliey, Springer for relevant literature, focusing on flavonoids extracted from herbal medicines, and summarizing how they can prevent endothelial dysfunction by inhibiting oxidative stress. Meanwhile, in our study, we found that flavonoid represented by quercetin and naringenin showed superior protective effects both in vivo and in vitro, suggesting the potential of flavonoid compounds in the treatment of AS.

Antiproliferative activity, cell-cycle arrest, apoptotic induction and LC-HRMS/MS analyses of extracts from two Linum species

CONTEXT

Linum is the largest genus of the Linaceae family; the species of this genus are known to have anticancer activity.

OBJECTIVE

In this study, ethyl acetate extracts of L. numidicum Murb. (EAELN) and L. trigynum L. (EAELT) were examined, for the first time, for their anticancer capacity. The secondary metabolites compositions were analysed by LC-HRMS/MS.

MATERIALS AND METHODS

The antiproliferative effect of EAELN and EAELT (0-10.000 μg/mL) against PC3 and MDA-MB-231 cell lines were  evaluated by the MTT assay after 72 h of treatment. Flow cytometer analysis of apoptosis (Annexin V-FITC/PI) and cell cycle (PI/RNase) was also performed after treatment with EAELN and EAELT at 250, 500, and 1000 μg/mL, for 24 h.

RESULTS

EAELN had the highest antiproliferative activity against PC3 (IC₅₀ 133.2 ± 5.73 μg/mL) and MDA-MB-231 (IC₅₀ 156.9 ± 2.83 μg/mL) lines, EAELN had also shown better apoptotic activity with 19 ± 2.47% (250 μg/mL), 87.5 ± 0.21% (500 μg/mL), and 92 ± 0.07% (1000 μg/mL), respectively, causing cell cycle arrest of PC3 cells in G2/M phase, whereas arrest in G0/G1 and G2/M phases was observed after treatment with EAELT. LC-HRMS/MS profiling of the extracts revealed the presence of known compounds that might be responsible for the observed anticancer activity such as chicoric acid, vicenin-2, vitexin and podophyllotoxin-β-d-glucoside.

DISCUSSION AND CONCLUSIONS

We have shown, for the first time, that EAELN and EAELT exert anticancer activity through cell cycle arrest and induction of apoptosis. EAELN can be considered as a source to treat cancer. Further studies will be required to evaluate the effect of the active compounds, once identified, on other cancer cell lines.

Advances and Challenges in Enzymatic C-glycosylation of Flavonoids in Plants

Flavonoid glycosides play required determinant roles in plants and have considerable potential for applications in medicine and biotechnology. Glycosyltransferases transfer a sugar moiety from uridine diphosphate-activated sugar molecules to an acceptor flavonoid via C-O and C-C linkages. Compared with O-glycosylflavonoids, C-glycosylflavonoids are more stable, are resistant to glycosidase or acid hydrolysis, exhibit better pharmacological properties, and have received more attention. Herein, we discuss the mining of C-glycosylflavones and the corresponding C-glycosyltransferases and evaluate the differences in structure and catalytic mechanisms between C-glycosyltransferase and O-glycosyltransferase. We conclude that promiscuity and specificity are key determinants for general flavonoid C-glycosyltransferase engineering and summarize the C-glycosyltransferase engineering strategy. A thorough understanding of the properties, catalytic mechanisms, and engineering of C-glycosyltransferases will be critical for any future biotechnological applications in areas such as the production of desired C-glycosylflavonoids for nutritional or medicinal use.

Anticancer Potential of Moringa oleifera on BRCA-1 Gene: Systems Biology

Breast cancer has consistently been a global challenge that is prevalent among women. There is a continuous increase in the high number of women mortality rates because of breast cancer and affecting nations at all modernization levels. Women with high-risk factors, including hereditary, obesity, and menopause, have the possibility of developing breast cancer growth. With the advent of radiotherapy, chemotherapy, hormone therapy, and surgery in breast cancer treatment, breast cancer survivors have increased. Also, the design and development of drugs targeting therapeutic enzymes effectively treat the tumour cells early. However, long-term use of anticancer drugs has been linked to severe side effects. This research aims to develop potential drug candidates from Moringa oleifera, which could serve as anticancer agents. In silico analysis using Schrödinger Molecular Drug Discovery Suite and SWISS ADME was employed to determine the therapeutic potential of phytochemicals from M oleifera against breast cancer via molecular docking, pharmacokinetic parameters, and drug-like properties. The result shows that rutin, vicenin-2, and quercetin-3-O-glucoside have the highest binding energy of −7.522, −6.808, and −6.635 kcal/mol, respectively, in the active site of BRCA-1. The essential amino acids involved in the protein-ligand interaction following active site analysis are ASN 1678, ASN 1774, GLY 1656, LEU 1657, GLN 1779, LYS 1702, SER 1655, PHE 1662, ARG 1699, GLU 1698, and VAL 1654. Thus, we propose that bioactive compounds from M oleifera may be potential novel drug candidates in the treatment of breast cancer.

Vascular Dysfunction in Diabetes and Obesity: Focus on TRP Channels

Transient receptor potential (TRP) superfamily consists of a diverse group of non-selective cation channels that has a wide tissue distribution and is involved in many physiological processes including sensory perception, secretion of hormones, vasoconstriction/vasorelaxation, and cell cycle modulation. In the blood vessels, TRP channels are present in endothelial cells, vascular smooth muscle cells, perivascular adipose tissue (PVAT) and perivascular sensory nerves, and these channels have been implicated in the regulation of vascular tone, vascular cell proliferation, vascular wall permeability and angiogenesis. Additionally, dysfunction of TRP channels is associated with cardiometabolic diseases, such as diabetes and obesity. Unfortunately, the prevalence of diabetes and obesity is rising worldwide, becoming an important public health problems. These conditions have been associated, highlighting that obesity is a risk factor for type 2 diabetes. As well, both cardiometabolic diseases have been linked to a common disorder, vascular dysfunction. In this review, we briefly consider general aspects of TRP channels, and we focus the attention on TRPC (canonical or classical), TRPV (vanilloid), TRPM (melastatin), and TRPML (mucolipin), which were shown to be involved in vascular alterations of diabetes and obesity or are potentially linked to vascular dysfunction. Therefore, elucidation of the functional and molecular mechanisms underlying the role of TRP channels in vascular dysfunction in diabetes and obesity is important for the prevention of vascular complications and end-organ damage, providing a further therapeutic target in the treatment of these metabolic diseases.

Healing Effect of Vicenin-2 (VCN-2) on Human Dermal Fibroblast (HDF) and Development VCN-2 Hydrocolloid Film Based on Alginate as Potential Wound Dressing

Chronic wounds represent serious globally health care and economic issues especially for patients with hyperglycemic condition. Wound dressings have a predominant function in wound treatment; however, the dressings for the long-lasting and non-healing wounds are still a significant challenge in the wound care management market. Astonishingly, advanced wound dressing which is embedded with a synthetic drug compound in a natural polymer compound that acts as drug release carrier has brought about promising treatment effect toward injured wound. In the current study, results have shown that Vicenin-2 (VCN-2) compound in low concentration significantly enhanced cell proliferation and migration of HDF. It also regulated the production of pro-inflammatory cytokines such as IL-6, IL-1β, and TNF-α from HDF in wound repair. Treatment of VCN-2 also has facilitated the expression of TGF-1β and VEGF wound healing maker in a dose-dependent manner. A hydrocolloid film based on sodium alginate (SA) incorporated with VCN-2 synthetic compound which targets to promote wound healing particularly in diabetic condition was successfully developed and optimized for its physico-chemical properties. It was discovered that all the fabricated film formulations prepared were smooth, translucent, and good with flexibility. The thickness and weight of the formulations were also found to be uniform. The hydrophilic polymer comprised of VCN-2 were shown to possess desirable wound dressing properties and superior mechanical characteristics. The drug release profiles have revealed hydrocolloid film, which is able to control and sustain the VCN-2 released to wound area. In short, hydrocolloid films consisting of VCN-2 formulations are suitably used as a potential wound dressing to promote restoration of wound injury.

Plant-Based Antidiabetic Nanoformulations: The Emerging Paradigm for Effective Therapy

Diabetes mellitus is a life-threatening metabolic syndrome. Over the past few decades, the incidence of diabetes has climbed exponentially. Several therapeutic approaches have been undertaken, but the occurrence and risk still remain unabated. Several plant-derived small molecules have been proposed to be effective against diabetes and associated vascular complications via acting on several therapeutic targets. In addition, the biocompatibility of these phytochemicals increasingly enhances the interest of exploiting them as therapeutic negotiators. However, poor pharmacokinetic and biopharmaceutical attributes of these phytochemicals largely restrict their clinical usefulness as therapeutic agents. Several pharmaceutical attempts have been undertaken to enhance their compliance and therapeutic efficacy. In this regard, the application of nanotechnology has been proven to be the best approach to improve the compliance and clinical efficacy by overturning the pharmacokinetic and biopharmaceutical obstacles associated with the plant-derived antidiabetic agents. This review gives a comprehensive and up-to-date overview of the nanoformulations of phytochemicals in the management of diabetes and associated complications. The effects of nanosizing on pharmacokinetic, biopharmaceutical and therapeutic profiles of plant-derived small molecules, such as curcumin, resveratrol, naringenin, quercetin, apigenin, baicalin, luteolin, rosmarinic acid, berberine, gymnemic acid, emodin, scutellarin, catechins, thymoquinone, ferulic acid, stevioside, and others have been discussed comprehensively in this review.

Functional Characterization and Structural Basis of an Efficient Di-C-glycosyltransferase from Glycyrrhiza glabra

A highly efficient di-C-glycosyltransferase GgCGT was discovered from the medicinal plant Glycyrrhiza glabra. GgCGT catalyzes a two-step di-C-glycosylation of flopropione-containing substrates with conversion rates of >98%. To elucidate the catalytic mechanisms of GgCGT, we solved its crystal structures in complex with UDP-Glc, UDP-Gal, UDP/phloretin, and UDP/nothofagin, respectively. Structural analysis revealed that the sugar donor selectivity was controlled by the hydrogen-bond interactions of sugar hydroxyl groups with D390 and other key residues. The di-C-glycosylation capability of GgCGT was attributed to a spacious substrate-binding tunnel, and the G389K mutation could switch di- to mono-C-glycosylation. GgCGT is the first di-C-glycosyltransferase with a crystal structure, and the first C-glycosyltransferase with a complex structure containing a sugar acceptor. This work could benefit the development of efficient biocatalysts to synthesize C-glycosides with medicinal potential.

Antihyperglycaemic, haemorheological and antioxidant activities of Lychnis chalcedonica L. extract in a streptozotocin-induced rat model of diabetes mellitus

Background New therapeutic strategies, such as the use of agents to correct rheological disorders, are needed for the prevention and treatment of angiopathy in diabetic patients. The aim of this work was to study the antihyperglycaemic, haemorheologic and antioxidant activities of an extract from the flowering plant Lychnis chalcedonica L. (ELC) and 20-hydroxyecdysone using the streptozotocin-induced model of diabetic rats. Methods The streptozotocin-induced model of diabetes was produced using streptozotocin at a dose of 50 mg/kg (ip). Animals from the experimental groups were treated with ELC (150 mg/kg) or 20-hydroxyecdysone (1.1 mg/kg) intragastrically in 1% aqueous starch mucilage daily, for 14 days; rats of control groups received an equal volume of starch mucilage. The following parameters were measured: glucose concentration (GC) in blood, whole blood viscosity (WBV), conjugated dienes in RBC membranes. Macro- and microrheological indicators (viz. plasma viscosity, haematocrit, RBC aggregation (T1/2) and the RBC elongation index (EI)) were additionally measured in rats that received ELC, and in the control group. Results After treatment with ELC, the GC in rats was 19% lower than that in the control group (14.7 ± 0.9 mM compared to 18.2 ± 1.1 mM). Rats with streptozotocin-induced diabetes have hyperviscosity syndrome, which is characterized by increased WBV, increased RBC aggregation and decreased deformability. ELC treatment reduced WBV at shear rates of 10-90 s-1 by 5-8%, and T1/2 and EI in the experimental group were 31% and 5-10% higher compared to the control group. 20-Hydroxyecdysone decreased WBV at shear rates of 10-90 s-1 by 3-11%. Finally, ELC and 20-hydroxyecdysone lowered the content of conjugated dienes by 27% and by 26% compared to the control groups. Conclusion In the streptozotocin-induced diabetic rat model, ELC showed measurable antihyperglycaemic activity; ELC and 20-hydroxyecdysone demonstrated similar haemorheological, and antioxidant activities.

Adipose tissue as a possible therapeutic target for polyphenols: A case for Cyclopia extracts as anti-obesity nutraceuticals

Obesity is a significant contributor to increased morbidity and premature mortality due to increasing the risk of many chronic metabolic diseases such as type 2 diabetes, cardiovascular disease and certain types of cancer. Lifestyle modifications such as energy restriction and increased physical activity are highly effective first-line treatment strategies used in the management of obesity. However, adherence to these behavioral changes is poor, with an increased reliance on synthetic drugs, which unfortunately are plagued by adverse effects. The identification of new and safer anti-obesity agents is thus of significant interest. In recent years, plants and their phenolic constituents have attracted increased attention due to their health-promoting properties. Amongst these, Cyclopia, an endemic South African plant commonly consumed as a herbal tea (honeybush), has been shown to possess modulating properties against oxidative stress, hyperglycemia, and obesity. Likewise, several studies have reported that some of the major phenolic compounds present in Cyclopia spp. exhibit anti-obesity effects, particularly by targeting adipose tissue. These phenolic compounds belong to the xanthone, flavonoid and benzophenone classes. The aim of this review is to assess the potential of Cyclopia extracts as an anti-obesity nutraceutical as underpinned by in vitro and in vivo studies and the underlying cellular mechanisms and biological pathways regulated by their phenolic compounds.

Hepatoprotective effects of vicenin-2 and scolymoside through the modulation of inflammatory pathways

The aim of this study was to investigate the effects of two structurally related flavonoids found in Cyclopia subternata, vicenin-2 (VCN) and scolymoside (SCL) on lipopolysaccharide (LPS)-induced liver failure in mice and to elucidate underlying mechanisms. Mice were treated intravenously with VCN or SCL at 12 h after LPS treatment. LPS significantly increased mortality, serum levels of alanine transaminase, aspartate transaminase, and inflammatory cytokines, and toll-like receptor 4 (TLR4) protein expression; these effects of LPS were inhibited by VCN or SCL. It also attenuated the LPS-induced activation of myeloid differentiation primary response gene 88 and TLR-associated activator of interferon-dependent signaling pathways of the TLR system. Our results suggest that VCN or SCL protects against LPS-induced liver damage by inhibiting the TLR-mediated inflammatory pathway, indicating its potential to treat liver diseases.

Endothelial permeability, LDL deposition, and cardiovascular risk factors-a review

Early atherosclerosis features functional and structural changes in the endothelial barrier function that affect the traffic of molecules and solutes between the vessel lumen and the vascular wall. Such changes are mechanistically related to the development of atherosclerosis. Proatherogenic stimuli and cardiovascular risk factors, such as dyslipidaemias, diabetes, obesity, and smoking, all increase endothelial permeability sharing a common signalling denominator: an imbalance in the production/disposal of reactive oxygen species (ROS), broadly termed oxidative stress. Mostly as a consequence of the activation of enzymatic systems leading to ROS overproduction, proatherogenic factors lead to a pro-inflammatory status that translates in changes in gene expression and functional rearrangements, including changes in the transendothelial transport of molecules, leading to the deposition of low-density lipoproteins (LDL) and the subsequent infiltration of circulating leucocytes in the intima. In this review, we focus on such early changes in atherogenesis and on the concept that proatherogenic stimuli and risk factors for cardiovascular disease, by altering the endothelial barrier properties, co-ordinately trigger the accumulation of LDL in the intima and ultimately plaque formation.

Anti-inflammatory effects of Vicenin-2 on dextran sulfate sodium-induced colitis in mice

The objective of the present work was to evaluate the anti-inflammatory effects of Vicenin-2 on dextran sulfate sodium (DSS)-induced colitis model. Colitis was induced in C57BL/6J mice by administration of 2% DSS in drinking water for 7 days. In addition to DSS, Vicenin-2 (50 mg kg^-1 /day^-1 ) was administrated orally to the test group. The ulceration extent and severity were assessed macroscopically, histopathologically, and by disease activity index. The Vicenin-2 treated group showed significant differences in physiological parameters including bodyweight, colon weight, and colon length, compared to DSS-induced colitis group. In addition, Vicenin-2 treatment effectively reduced stool consistency and bleeding scores. Myeloperoxidase (MPO) activity, expressions of pro-inflammatory cytokines, and specific key inflammatory markers (iNOS and COX-2) significantly increased in DSS-induced colitis colon tissues. However, administration of Vicenin-2 effectively reduced the MPO activity, attenuated the expression of pro-inflammatory cytokines and key inflammatory markers, in DSS-induced colitis mice. These results were comparable with sulfasalazine, an anti-inflammatory drug used routinely for ulcerative colitis (UC). These findings suggest that Vicenin-2 effectively suppresses DSS-induced colitis by attenuating expressions of key inflammatory mediators and found to be an attractive therapeutic drug for treating UC.

Targeting epigenetics and non-coding RNAs in atherosclerosis: from mechanisms to therapeutics

Atherosclerosis, the principal cause of cardiovascular death worldwide, is a pathological disease characterized by fibro-proliferation, chronic inflammation, lipid accumulation, and immune disorder in the vessel wall. As the atheromatous plaques develop into advanced stage, the vulnerable plaques are prone to rupture, which causes acute cardiovascular events, including ischemic stroke and myocardial infarction. Emerging evidence has suggested that atherosclerosis is also an epigenetic disease with the interplay of multiple epigenetic mechanisms. The epigenetic basis of atherosclerosis has transformed our knowledge of epigenetics from an important biological phenomenon to a burgeoning field in cardiovascular research. Here, we provide a systematic and up-to-date overview of the current knowledge of three distinct but interrelated epigenetic processes (including DNA methylation, histone methylation/acetylation, and non-coding RNAs), in atherosclerotic plaque development and instability. Mechanistic and conceptual advances in understanding the biological roles of various epigenetic modifiers in regulating gene expression and functions of endothelial cells (vascular homeostasis, leukocyte adhesion, endothelial-mesenchymal transition, angiogenesis, and mechanotransduction), smooth muscle cells (proliferation, migration, inflammation, hypertrophy, and phenotypic switch), and macrophages (differentiation, inflammation, foam cell formation, and polarization) are discussed. The inherently dynamic nature and reversibility of epigenetic regulation, enables the possibility of epigenetic therapy by targeting epigenetic "writers", "readers", and "erasers". Several Food Drug Administration-approved small-molecule epigenetic drugs show promise in pre-clinical studies for the treatment of atherosclerosis. Finally, we discuss potential therapeutic implications and challenges for future research involving cardiovascular epigenetics, with an aim to provide a translational perspective for identifying novel biomarkers of atherosclerosis, and transforming precision cardiovascular research and disease therapy in modern era of epigenetics.

Hydroxysafflor yellow A attenuates high glucose-induced human umbilical vein endothelial cell dysfunction

High glucose (HG) induces vascular injury in diabetes. Hydroxysafflor yellow A (HSYA) has been used to ameliorate ischemic cardiovascular diseases in China for many years. In the present study, we assessed whether HSYA has a potential protective role in HG-induced human umbilical vein endothelial cell (HUVEC) injury. Cell viability was determined with an 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Cell apoptosis was detected by fluorescein isothiocyanate/propidium iodide staining assay. The endothelial cell permeability was measured with a permeability assay. Cell adhesion molecule (CAM) expression, vascular endothelial growth factor, and basic fibroblast growth factor levels were detected with an enzyme-linked immunosorbent assay. Reactive oxygen species (ROS) formation was measured with a DCF-DA assay. Protein expression of NADPH oxidase 4 (NOX4) was measured by Western blotting. Our data indicated that HG increases HUVEC apoptosis, vascular permeability, monocyte adhesion, the level of CAMs, the formation of ROS, and NOX4 expression. Our data revealed that HG increases vascular injury, which is attenuated by HSYA. Because vascular inflammation has a key role in the development of diabetes mellitus, our results implied that HSYA is considered as a potential agent for diabetic vascular injury treatment.

Structure Identification of ViceninII Extracted from Dendrobium officinale and the Reversal of TGF-β1-Induced Epithelial⁻Mesenchymal Transition in Lung Adenocarcinoma Cells through TGF-β/Smad and PI3K/Akt/mTOR Signaling Pathways

ViceninII is a naturally flavonoid glycoside extracted from Dendrobium officinale, a precious Chinese traditional herb, has been proven to be valuable for cancer treatment. Transforming growth factor-β1 (TGF-β1), promotes the induction of epithelial–mesenchymal transition (EMT), a process involved in the metastasis of cells that leads to enhanced migration and invasion. However, there is no previously evidence that ViceninII has an inhibitory effect on cancer metastasis, specifically on the TGF-β1-induced EMT process in lung adenocarcinoma cells. In this experiment, we used UV, ESIMS, and NMR to identify the structure of ViceninII.A549 and H1299 cells were treated with TGF-β1 in the absence and presence of ViceninII, and subsequent migration and invasion were measured by wound-healing and transwell assays. The protein localization and expressions were detected by immunofluorescence and Western blotting. The results indicated that TGF-β1 induced spindle-shaped changes, increased migration and invasion, and upregulated or downregulated the relative expression of EMT biomarkers. Meanwhile, these alterations were significantly inhibited when co-treated with ViceninII and inhibitors LY294002 and SB431542. In conclusion, ViceninII inhibited TGF-β1-induced EMT via the deactivation of TGF-β/Smad and PI3K/Akt/mTOR signaling pathways.This is the first time that the anti-metastatic effects of ViceninII have been demonstrated, and their molecular mechanisms provided.

Vicenin-2 inhibits Wnt/β-catenin signaling and induces apoptosis in HT-29 human colon cancer cell line

Background

Colorectal cancer (CRC) is among highest prevailing cancers in the whole world, especially in western countries. For a diverse of reasons, patients prefer naturally occurring dietary substances over synthetic agents to prevent cancer. Vicenin-2 is largely available in a medicinal plant Ocimum sanctum and is an apigenin form, 6,8-di-C-glucoside, which has been reported to have a range of pharmacological values which includes antioxidant, hepatoprotective, anti-inflammatory and anti-cancer. This study was aimed to analyze the anti-proliferative effect of Vicenin-2 on human colon cancer cells via the Wnt/β-catenin signaling inhibition.

Methods

MTT assay was used to assess the cell viability at different concentrations and time point. Vicenin-2 at a concentration of 50 µM (IC₅₀) decreased the phosphorylated (inactive) glycogen synthase kinase-3β, cyclin D1, and non-p-β-catenin expressions in HT-29 cells, which were evidenced through western blot analysis.

Results

Further, Vincenin-2 reduced the T-cell factor (TCF) / Leukocyte erythroid factor (LEF) reporter activity in HT-29 cells. Vicenin-2 also promoted substantial cell cycle arrest at the G₂M phase of HT-29 cells, as well induced apoptosis in HT-29 cells, as revealed through flow cytometric analysis. Furthermore, immunoblot analysis showed that Vicenin-2 treatment enhanced the expression of Cytochrome C, Bax and caspase-3 whereas suppressed the Bcl-2 expression.

Conclusion

Together, these results revealed that Vicenin-2 can act as a potent inhibitor of HT-29 cell proliferation and can be used as an agent against CRC.

TET-2 up-regulation is associated with the anti-inflammatory action of Vicenin-2

Vicenin-2, a C-glycoside flavone that is present in many plant sources, exerts potent anti-inflammatory effects in a number of cell and animal models of inflammation. Ten-eleven translocation (TET)-2 has recently gained considerable attention due to the role it plays in regulating the inflammasome. We studied the ability of Vicenin-2 (V-2) to regulate a range of lipopolysaccharide (LPS) stimulated inflammatory activities in PMA-differentiated THP-1 cells and human primary mononuclear cells. We also investigated the action of V-2 on the secretion of NLRP3 inflammasome regulated cytokines (IL-1β and IL-18) by ELISA, and determined if V-2 can regulate the expression of NLRP3, IL-10, IL-1Ra and TET-2. The effect of V-2 on NF-κB signalling was investigated by fluorescence microscopy and gene reporter assay. Additionally, the effect of V-2 on LPS-induced phosphorylation of IKB-α was also investigated by Western blot analysis. V-2 down-regulated LPS-induced secretion of proinflammatory cytokines (TNF-α and IL-1β), in both THP-1 and primary mononuclear cells. V-2 also decreased the LPS-stimulated secretion of IL-18 in THP-1 cells. V-2 significantly down-regulated TNF-α induced NF-κB reporter activity in HEK293T transfected cells and attenuated IKB-α phosphorylation in THP-1 cells. V-2 treatment also induced enhanced nuclear staining of the p50 subunit and reduced p65 subunit of NF-κB. V-2 treatment alone increased the expression of anti-inflammatory cytokine, IL-10, and the regulator of the inflammasome; IL-1Ra, in the presence of LPS. V-2 also significantly decreased LPS-induced NLRP3 expression while concomitantly increasing TET-2 expression. This study demonstrates that the anti-inflammatory actions of V-2 are associated not only with increased IL-10 and IL-1Ra expression, but also with TET-2 up-regulation. Further work is required to establish if the effects of V-2 can be definitively linked to TET-2 activity and that these actions are mirrored in a range of relevant cell types.