Cyanidin 3-glucoside ameliorates hyperglycemia and insulin sensitivity due to downregulation of retinol binding protein 4 expression in diabetic mice

Dietary plant flavonoids in prevention of obesity and diabetes

Obesity and diabetes are the most prevailing chronic metabolic diseases worldwide from mainly lipid and glucose metabolic dysfunctions and their incidence is increasing at an alarming high rate. Obesity is characterized by excess fat accumulation in WAT and liver and is the central player of insulin resistance in the peripheral tissues from chronic inflammation, lipotoxicity and gut dysbiosis, and plays a key role for development of type 2 diabetes (T2DM) and vascular diseases. Diabetes mellitus, known as diabetes, is chiefly characterized by hyperglycaemia from impaired insulin secretion and insulin resistance. Several identified mutant genes in insulin secretion and resistance and various environmental factors are considered responsible for the onset of this disease. Currently available oral synthetic drugs, biguanides, incretin mimetic, GLP-1R and PPAR agonists and DPP-4 inhibitors for management of obesity and diabetes have several adverse effects in patients on long-term use. Emerging evidence supports the efficacy of dietary plant flavonoids in prevention and attenuation of obesity and diabetes by the protection and proliferation of pancreatic beta-cells and improvement of their insulin secretory function via activation of cAMP/PKA signaling pathway as well as in the improvement of insulin sensitivity in the peripheral metabolic tisssues for glucose uptake and utilization via inhibition of inflammation, lipotoxicity and oxidative stress. These flavonoids improve GLUT-4 expression and translocation to plasma membrane by activation of insulin-sensitive PI3K/Akt signaling and insulin-independent AMPK, SIRT-1 and MOR activation pathways for regulation of glucose homeostasis, and improve fat oxidation and reduce lipid synthesis by regulation of related genes for lipid homeostasis in the body of obese diabetic animals. In this chapter, we have highlighted all these beneficial anti-obesity and antidiabetic potentials of some dietary plant flavonoids along with their molecular actions, bioavailability and pharmacokinetics. In addition, the present understanding and management of obesity and diabetes are also focused.

Effects of phytochemicals on cellular signaling: reviewing their recent usage approaches

Most of the previous studies in last three decades report evidence of interactions between the different phytochemicals and the proteins involved in signal transduction pathways using in silico, in vitro, ex vivo, and in vivo analyses. However, extrapolation of these findings for clinical purposes has not been that fruitful. The efficacy of the phytochemicals in vivo studies is limited by parameters such as solubility, metabolic degradation, excretion, etc. Various approaches have now been devised to circumvent these limitations. Recently, chemical modification of the phytochemicals are demonstrated to reduce some of the limitations and improve their efficacy. Similar to traditional medicines several combinatorial phytochemical formulations have shown to be more efficient. Further, phytochemicals have been reported to be even more efficient in the form of nanoparticles. However, systematic evaluation of their efficacy, mode of action in pathway modulation, usage and associated challenges is required to be done. The present review begins with basic understanding of how signaling cascades regulate cellular response and the consequences of their dysregulation further summarizing the developments and problems associated with the dietary phytochemicals and also discuss recent approaches in strengthening these compounds in pharmacological applications. Only context relevant studies have been reviewed. Considering the limitations and scope of the article, authors do not claim inclusion of all the early and recent studies.

Effects of Blackcurrant Anthocyanin on Endothelial Function and Peripheral Temperature in Young Smokers

Background: Blackcurrant anthocyanin (BCA) is expected to repair endothelial dysfunction, but it remains unclear whether beneficial effects are present in young healthy persons. This study examines whether supplements containing blackcurrant anthocyanin improve endothelial function and peripheral temperature in young smokers. Methods: Young, healthy male nonsmokers (N group: n = 11; mean age 22 ± 2 years) and smokers (S group: n = 13; mean age 21 ± 1 years) were enrolled. A randomized and double-blind trial was designed to compare the effects of no supplement, a supplement containing 50 mg of blackcurrant anthocyanin (supplement A), and a supplement containing 50 mg of blackcurrant anthocyanin plus vitamin E (supplement B) on flow-mediated dilatation (FMD) and skin temperature. Results: Under no supplement, FMD was unchanged during the 2 h period after smoking in the N group, whereas it was decreased during the 2 h period after smoking in the S group. Under the A supplement, FMD was decreased 1 h after smoking and returned to the baseline level 2 h after smoking in the S group. The skin temperature in the area of the foot dorsum was decreased in the S group after smoking compared with that in the N group, who did not smoke, whereas under A and B supplements, it was higher in the S group compared with that in the N group. Conclusions: BCA could attenuate the smoking-induced acute endothelial dysfunction and improve peripheral temperature in young smokers.

Sweet Cherry Extract Targets the Hallmarks of Cancer in Prostate Cells: Diminished Viability, Increased Apoptosis and Suppressed Glycolytic Metabolism

The present work evaluated the anticancer properties of sweet cherry (Prunus avium) extract on human prostate cells. Several sweet cherry cultivars from Fundão (Portugal) were methanol-extracted and their phytochemical composition characterized. The Saco "late harvest" extract was highly-enriched in anthocyanins and selected for use in biological assays. Non-neoplastic (PNT1A) and neoplastic (LNCaP and PC3) human prostate cells were treated with 0-2,000 μg/ml of extract for 48-96 h. Cell viability was evaluated by the MTT assay. Apoptosis, oxidative stress, and glycolytic metabolism were assessed by Western blotting and enzymatic assays. Glucose consumption and lactate production were measured spectrophotometrically. Saco cherry extract diminished the viability of neoplastic and non-neoplastic cells, whereas enhancing apoptosis in LNCaP. Cherry extract-treatment also diminished oxidative damage and suppressed glycolytic metabolism in LNCaP cells. These findings widened the knowledge on the mechanisms by which cherry extract modulate cell physiology, demonstrating their broad action over the hallmarks of cancer.

Antidiabetic and Antioxidative Potential of the Blue Congo Variety of Purple Potato Extract in Streptozotocin-Induced Diabetic Rats

This study was designed to evaluate the effects of purple potato extract of the Blue Congo variety (PP) on diabetes and its antioxidant activities after two-week administration tostreptozotocin (STZ)-induced diabetic rats. The activities of PP were evaluated at a dose of 165 mg/kg body weight (b.w.) by estimating biochemical changes in blood plasma and through a histopathological study of kidney, muscles, and liver tissue. We evaluated the effect of treatment with extract on glucose level, glycated hemoglobin, activities of enzymatic antioxidants (including superoxide dismutase, glutathione peroxidase, and catalase), and lipid peroxidation. Moreover, we determined advanced glycation end-products (AGEs), advanced oxidation protein products (AOPPs), and the level of oxidative modified proteins (OMPs) as markers of carbonyl-oxidative stress in rats with diabetes. Using high-performance liquid chromatography, we identified five anthocyanins and six phenolic acids in the extract from Blue Congo with the dominant acylated anthocyanin as petunidin-3-p-coumaroyl-rutinoside-5-glucoside. The administration of Blue Congo extract lowered blood glucose, improved glucose tolerance, and decreased the amount of glycated hemoglobin. Furthermore, PP demonstrated an antioxidative effect, suppressed malondialdehyde levels, and restored antioxidant enzyme activities in diabetic rats. After administration of PP, we also noticed inhibition of OMP, AGE, and AOPP formation in the rats' blood plasma.

Myocardial Protection from Ischemia-Reperfusion Damage by the Antioxidant Effect of Hibiscus sabdariffa Linnaeus on Metabolic Syndrome Rats

Cardiovascular diseases (CVD) constitute one of the most prevalent health problems worldwide, being strongly associated with metabolic syndrome (MS). Oxidative stress (OS) is present in both CVD and MS. Infusions of Hibiscus sabdariffa Linnaeus (HSL) have antioxidant properties and could therefore decrease the presence of OS in these diseases. The aim of this study was to evaluate myocardial protection during ischemia/reperfusion due to the antioxidant effect of HSL infusion (3%) on a MS rat model induced by the administration of 30% sucrose in drinking water. We determined in control, MS, and MS + HSL rat hearts (n = 6 per group) cardiac mechanical performance (CMP), coronary vascular resistance (CVR), and activities of manganese and copper/zinc superoxide dismutases (Mn and Cu/Zn-SOD), peroxidases, glutathione peroxidase (GPx), catalase (CAT), glutathione s-transferase (GST), glutathione reductase (GR), and glutathione (GSH). We also determined lipoperoxidation (LPO), total antioxidant capacity (TAC), and the nitrate/nitrite ratio (NO₃⁻/NO₂⁻). The treatment with the HSL infusion restored the CMP (p = 0.01) and CVR (p = 0.04) and increased the Mn- (p = 0.02), Cu/Zn-SOD (p = 0.05), peroxidases (p = 0.04), GST (p = 0.02) activity, GHS (p = 0.02), TAC (p = 0.04), and NO₃⁻/NO₂⁻ (p = 0.01) and decreased the LPO (p = 0.02) in the heart of MS rats undergoing ischemia/reperfusion. The results suggest that the treatment with an infusion from HSL calices protects the cardiac function from damage by ischemia and reperfusion through the antioxidant activities of the substances it possesses. It favors antioxidant enzymatic activities and nonenzymatic antioxidant capacity.

Endogenously Synthesized n-3 Polyunsaturated Fatty Acids in Pregnant fat-1 Mice Decreases Mammary Cancer Risk of Female Offspring by Regulating Expression of Long Noncoding RNAs

SCOPE

The present study investigates the precise mechanism by which maternal n-3 PUFAs decrease mammary cancer risk of offspring in terms of epigenetics.

METHODS AND RESULTS

Transgenic fat-1 and wild-type C57BL/6J littermates are fed an n-6 PUFAs diet during pregnancy. Wild-genotype offspring of fat-1 mothers (fat-1 group) are compared with wild-genotype offspring of C57BL/6J mothers (control group) in breast cancer risk. Fat-1 group shows a significantly lower tumor incidence and smaller tumor volume compared with control group. n-3 PUFAs in fat-1 mothers change the expression of long noncoding RNA (lncRNA, 53 upregulated and 45 downregulated) in mammary glands of offspring. The lncRNA changes are associated with the changes of mRNA in multiple oncogenic signaling pathways, especially NF-κB, Jak-STAT, and MAPK pathways. Expression of key protein in these pathways, namely p65, p60, STAT3, Jak1, and p38, are significantly inhibited in fat-1 group. In line with these results, reduced proliferation and increased apoptosis are also observed in mammary epithelial of fat-1 group than control group.

CONCLUSION

The anticancer effect of maternal n-3 PUFAs is related to the regulation of lncRNA expression, which can further regulate the susceptibility of offspring to breast cancer.

Instant White Rice with Pigmented Giant Embryonic Rice Improves Glucose Metabolism and Inhibits Oxidative Stress in High-Fat Diet-Fed Mice

The effects of instant cooked rice made from a combination of white rice and pigmented giant embryonic Keunnunjami rice, in comparison with those of instant regular white or brown rice and instant non-pigmented giant embryonic brown rice, on the glucose metabolism and antioxidant defense status in high-fat diet-fed mice were investigated. 56 male C57BL/6N mice were randomly divided into 7 dietary groups: normal control, high fat (23 %, HF), and HF supplemented with normal white (HF + NW) or brown rice (HF + NB), non-pigmented giant embryonic rice (HF + GB), and white rice with 8 % Keunnunjami (HF + KJ8) and 18 % Keunnunjami (HF + KJ18). After 7 weeks, HF mice showed marked increases in blood glucose (156 mg/dL), plasma insulin (12.1 mg/mL), and lipid peroxidation, and a significant decrease in hepatic glycogen (14.2 mg/g) relative to the control group (p < 0.05). However, addition of instant NB, GB, KJ8, andKJ18) rice suppressed this high-fat diet-induced hyperglycemia and oxidative stress through altering glucose-regulating enzymes (glucokinase, glucose-6-phosphatase, and phosphoenolpyruvate carboxykinase) and activation of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase, glutathione reductase, and paraoxonase). Compared with HF mice, HF + KJ8 and HF + KJ18 groups exhibited significantly lower glucose (139-141 mg/dL), insulin (10.6-10.9 mg/mL), and lipid peroxidation and higher glycogen (15.3-16.4 mg/g) (p < 0.05). The hypoglycemic and antioxidant effects of instant KJ8 and KJ18 rice were generally comparable to those of instant NB and GB rice. These findings illustrate that instant rice made from white rice with 8 % Keunnunjami rice may be useful as a functional food with therapeutic potential against hyperglycemia and oxidative damage.

Jaboticaba peel powder and jaboticaba peel aqueous extract reduces obesity, insulin resistance and hepatic fat accumulation in rats

This study investigated the effects of freeze-dried jaboticaba peel (FJP) and jaboticaba tea (JE) on obesity parameters of diet-induced obese rats. Thirty-six male Wistar rats were distributed into six groups: AIN-93 M feed a normal control diet; HFF (obese control) feed a high-fat and fructose diet; Prevention FJP (P. FJP) and Treatment FJP (T. FJP) feed HFF diet with 2% of FJP powder, for 12 and 6 weeks respectively; Prevention JE (P. JE) and Treatment JE (T. JE) were feed with HFF diet and the water was substituted by JE, for 12 and 6 weeks, respectively. Lipid profile, glucose, adiponectin and leptin were measured. Glucose and insulin tolerance, also pancreatic islet insulin secretion were determined. Liver morphology and fat liver accumulation were evaluated. Results showed that HFF-diet induced weight gain, dyslipidemia, glucose intolerance, insulin resistance and hepatic steatosis. All FJP and JE treatments reduced weight gain, adiposity and improved insulin sensitivity. Twelve weeks supplementation increased HDL-cholesterol and prevented hepatic steatosis. Our results suggest that FJP and JE act as functional foods, being a dietary strategy to prevent or control obesity. FJP and JE 12 weeks supplementation can modulate important parameters of obesity and insulin metabolism, preventing liver steatosis in obese rats.

Health promoting properties of blueberries: a review

With the strengthening of the link between diet and health, several foodstuffs have emerged as possessing potential health benefits such as phenolic rich fruits and vegetables. Blueberries, along with other berries, given their flavonoid and antioxidant content have long since been considered as a particularly interesting health promoting fruit. Therefore, the present work aimed to compile the existing evidences regarding the various potential benefits of blueberry and blueberry based products consumption, giving particular relevance to in vivo works and epidemiological studies whenever available. Overall, the results demonstrate that, while the evidences that support a beneficial role of blueberry and blueberry extracts consumption, further human based studies are still needed.

Cyanidin 3-O-glucoside prevents the development of maladaptive cardiac hypertrophy and diastolic heart dysfunction in 20-week-old spontaneously hypertensive rats

The present study investigated the effects of cyanidin 3-O-glucoside (C3G) in cardiomyocytes (CM) and fibroblasts exposed to endothelin 1 (ET1), as well as in the spontaneously hypertensive rat (SHR) model, alone or in combination with hydrochlorothiazide (HCT). Adult rat CM and cardiac fibroblasts (CF) were pretreated with C3G and co-incubated with ET1 (10-7 M) for 24 hours. Five-week-old male SHR and their normotensive controls, Wistar-Kyoto rats (WKY), received one of 4 treatments via oral gavage daily for 15 weeks: (1) water (control); (2) C3G (10 mg per kg per day); (3) HCT (10 mg per kg per day); (4) C3G + HCT (10 mg per kg per day each). Blood pressure (BP) was measured at 1, 8 and 15 weeks. Echocardiography measurements were performed at 15 weeks. C3G prevented ET1-induced CM death and hypertrophy. Stimulating CF with ET1 did not induce their phenoconversion; nevertheless, C3G inhibited un-stimulated CF differentiation. HCT slowed the rise of systolic BP (SBP) in the SHR over time (week 1: SHRs control = 161 ± 6.3 mmHg, SHRs HCT = 129 ± 6.3 mmHg; week 15: SHRs control = 201 ± 7.3 mmHg, SHRs HCT = 168 ± 7.3 mmHg), but C3G had no effect on SBP (week 1: SHRs control = 161 ± 6.3 mmHg, SHRs C3G = 126 ± 6.3 mmHg; week 15: SHRs control = 201 ± 7.3 mmHg, SHRs C3G = 186 ± 7.3 mmHg). SHRs treated with C3G, HCT, and C3G + HCT had lower left ventricular mass and shorter isovolumetric relaxation time compared to control SHRs. C3G ameliorated cardiac hypertrophy and diastolic dysfunction in SHRs.

Açaí (Euterpe oleracea Mart.) beverage consumption improves biomarkers for inflammation but not glucose- or lipid-metabolism in individuals with metabolic syndrome in a randomized, double-blinded, placebo-controlled clinical trial

Açaí (Euterpe oleracea Mart.) berries, characterized by high polyphenol concentrations (predominantly anthocyanins), have demonstrated anti-inflammatory and anti-diabetic activities. The study objective was to determine the modulation of lipid and glucose-metabolism, as well as oxidative stress and inflammation, by an açaí-beverage (containing 1139 mg L-1 gallic acid equivalents of total polyphenolics) in 37 individuals with metabolic syndrome (BMI 33.5 ± 6.7 kg m-2) who were randomized to consume 325 mL twice per d of a placebo control or açaí-beverage for 12 weeks. Anthropometric measurements, dietary intake, and blood and urine samples were collected at baseline and after 12 weeks of consumption. Two functional biomarkers, plasma level of interferon gamma (IFN-γ) and urinary level of 8-isoprostane, were significantly decreased after 12 weeks of açaí consumption compared to the placebo control (p = 0.0141 and 0.0099, respectively). No significant modification of biomarkers for lipid- and glucose-metabolism was observed in this study. Findings from this small pilot study provide a weak indication that the selected dose of açaí polyphenols may be beneficial in metabolic syndrome as only two biomarkers for inflammation and oxidative stress were improved over 12 weeks. Follow-up studies should be conducted with higher polyphenol-doses before drawing conclusions regarding the efficacy of açaí polyphenols in metabolic syndrome.

Differential effects of EPA, DPA and DHA on cardio-metabolic risk factors in high-fat diet fed mice

The aim of the present study was to assess and compare the effects of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) supplementation on lipid metabolism in 4 month-old male C57BL/6J mice fed a high-fat diet. The high-fat fed mice showed evidence of fatty liver, obesity and insulin resistance after being on the high-fat diet for 6 weeks compared with the control low-fat diet fed mice. Supplementation of the high-fat diet with either EPA, DPA or DHA prevented the fatty liver, prevented high serum cholesterol and serum glucose and prevented high liver cholesterol levels. DPA (but not EPA or DHA) was associated with a significantly improved homeostasis model assessment of insulin resistance (HOMA-IR) compared with the high-fat fed mice. Supplementation with DPA and DHA both prevented the decreased serum adiponectin levels, compared with EPA and the high-fat diet. In addition, supplementation with DPA and DHA both prevented the increased serum alanine aminotransferase (ALT) levels compared with EPA and the high-fat group, which can be attributed to down-regulation of TLR-4/NF-κB signaling pathway and decreasing lipogenesis in the liver. Therefore, DPA and DHA seem to exert similar effects in cardio-metabolic protection against the high-fat diet and these effects seem to be different to those of EPA.

Dietary flavonoids as a potential intervention to improve redox balance in obesity and related co-morbidities: a review

Obesity represents one of major health problems strongly linked to other co-morbidities, such as type 2 diabetes, CVD, gastrointestinal disorders and cognitive impairment. In this context, nutritional stress, such as an excess of fat intake, promotes a systemic oxidative stress, characterised by hyperproduction of reactive oxygen species, leading to cellular alterations that include impaired energy metabolism, altered cell signalling and cell cycle control, impaired cell transport mechanisms and overall dysfunctional biological activity. Flavonoids, dietary components of plant foods, are endowed with a wide spectrum of biological activities, including antioxidant activity, and have been proposed to reduce the risk of major chronic diseases. The present review intends to highlight and critically discuss the current scientific evidence on the possible effects of flavonoids in counteracting obesity and related co-morbidities (i.e. type 2 diabetes mellitus, CVD, gastrointestinal disorders and cognitive impairment) through a decrease in oxidative stress and related inflammatory conditions.

fat-1 mice prevent high-fat plus high-sugar diet-induced non-alcoholic fatty liver disease

High-fat and high-sugar (HFS) diets have been suggested to play a causal role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). This study aimed to investigate whether fat-1 transgenic mice with a higher tissue content of n-3 polyunsaturated fatty acids (PUFAs) could prevent HFS diet-induced NAFLD, compared with wild-type mice. The fat-1 and wild-type littermates had free access to a 15% fructose solution plus high-fat diet, a 15% glucose solution plus high-fat diet, or a 15% sucrose solution plus high-fat diet, respectively. Caloric intake, weight gain, biochemical parameters, histology, and gene and protein expression levels were measured after 8 weeks of intervention. Liquid intake in glucose- or sucrose-fed mice was about 2-fold compared with that in fructose-fed mice. The wild-type mice given glucose showed the highest total caloric intake and weight gain compared to the other groups. The serum concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and alanine transaminase (ALT) were significantly lowered in fat-1 groups compared with their paired wild-type groups. Histological analysis showed that the wild-type groups fed the HFS diets developed hepatic lipid accumulation and steatosis, compared with the fat-1 groups. The gene and protein expression levels involved in fatty acid synthesis and the toll-like receptor (TLR)-4 signaling pathway were significantly inhibited in the fat-1 groups compared with the wild-type groups. The endogenously synthesized n-3 PUFAs of the three fat-1 groups, which inhibit fatty acid synthesis and the TLR-4 signaling pathway, prevent HFS diet-induced NAFLD.

Serum Carotenoids Are Inversely Associated with RBP4 and Other Inflammatory Markers in Middle-Aged and Elderly Adults

(1) Background: Carotenoids may be inversely associated with inflammatory markers (i.e., TNF-α, IL-6, IL-1β). However, data are scarce on retinol binding protein 4 (RBP4) in humans. We examined the associations among serum carotenoids, RBP4 and several inflammatory markers in a Chinese population. (2) Methods: This community-based cross-sectional study included 3031 participants (68% males) aged 40-75 years in Guangzhou, China. Serum concentrations of carotenoids, RBP4, and inflammatory markers were measured. (3) Results: Generally, serum individual and total carotenoids were significantly and inversely associated with retinol-adjusted RBP4, RBP4, hsCRP, MCP1, and TNF-alpha levels. Age- and gender-adjusted partial correlation coefficients between total carotenoids and the above inflammatory markers were -0.129, -0.097, -0.159, -0.079, and -0.014 (all p < 0.01, except for TNF-alpha with p >0.05), respectively. The multivariate-adjusted values of partial correlation coefficients for these inflammation-related markers were -0.098, -0.079, -0.114, -0.090, and -0.079 (all p < 0.01), respectively. Among the individual carotenoids, those with the most predominant association were lutein-zeaxanthin and total carotenoids for retinol-adjusted RBP4 and RBP4, alpha- and beta-carotene for hsCRP, and alpha-carotene for MCP1 and TNF-alpha. No significant associations were observed for IL-6 and IL-1beta. (4) Conclusions: Serum carotenoids were inversely associated with RBP4, hsCRP, MCP1 and TNF-alpha among middle-aged and elderly Chinese adults.

Natural products for the treatment of type 2 diabetes mellitus: Pharmacology and mechanisms

Epidemiological studies have implied that diabetes mellitus (DM) will become an epidemic accompany with metabolic and endocrine disorders worldwide. Most of DM patients are affected by type 2 diabetes mellitus (T2DM) with insulin resistance and insulin secretion defect. Generally, the strategies to treat T2DM are diet control, moderate exercise, hypoglycemic and lipid-lowing agents. Despite the therapeutic benefits for the treatment of T2DM, most of the drugs can produce some undesirable side effects. Considering the pathogenesis of T2DM, natural products (NPs) have become the important resources of bioactive agents for anti-T2DM drug discovery. Recently, more and more natural components have been elucidated to possess anti-T2DM properties, and many efforts have been carried out to elucidate the possible mechanisms. The aim of this paper was to overview the activities and underlying mechanisms of NPs against T2DM. Developments of anti-T2DM agents will be greatly promoted with the increasing comprehensions of NPs for their multiple regulating effects on various targets and signal pathways.

Anti-Inflammatory and Anti-Obesity Properties of Food Bioactive Components: Effects on Adipose Tissue

Obesity is an epidemic and costly disease affecting 13% of the adult population worldwide. Obesity is associated with adipose tissue hypertrophy and hyperplasia, as well as pathologic endocrine alterations of adipose tissue including local and chronic systemic low-grade inflammation. Moreover, this inflammation is a risk factor for both metabolic syndrome (MetS) and insulin resistance. Basic and clinical studies demonstrate that foods containing bioactive compounds are capable of preventing both obesity and adipose tissue inflammation, improving obesity-associated MetS in human subjects and animal models of obesity. In this review, we discuss the anti-obesity and anti-inflammatory protective effects of some bioactive polyphenols of plant origin and omega-3 polyunsaturated fatty acids, available for the customers worldwide from commonly used foods and/or as components of commercial food supplements. We review how these bioactive compounds modulate cell signaling including through the nuclear factor-κB, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, toll-like receptors, and G-protein coupled receptor 120 intracellular signaling pathways and improve the balance of pro- and anti-inflammatory mediators secreted by adipose tissue and subsequently lower systemic inflammation and risk for metabolic diseases.

Dietary Anthocyanins and Insulin Resistance: When Food Becomes a Medicine

Insulin resistance is an abnormal physiological state that occurs when insulin from pancreatic β-cells is unable to trigger a signal transduction pathway in target organs such as the liver, muscles and adipose tissues. The loss of insulin sensitivity is generally associated with persistent hyperglycemia (diabetes), hyperinsulinemia, fatty acids and/or lipid dysregulation which are often prevalent under obesity conditions. Hence, insulin sensitizers are one class of drugs currently employed to treat diabetes and associated metabolic disorders. A number of natural products that act through multiple mechanisms have also been identified to enhance insulin sensitivity in target organs. One group of such compounds that gained interest in recent years are the dietary anthocyanins. Data from their in vitro, in vivo and clinical studies are scrutinized in this communication to show their potential health benefit through ameliorating insulin resistance. Specific mechanism of action ranging from targeting specific signal transduction receptors/enzymes to the general antioxidant and anti-inflammatory mechanisms of insulin resistance are presented.

Effects of Anthocyanins on Cardiometabolic Health: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Numerous clinical trials have examined the role of anthocyanins on cardiometabolic health, but their effects have not been quantitatively synthesized and systematically evaluated. The aim of our study was to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) assessing the effects of anthocyanins on glycemic regulation and lipid profiles in both healthy populations and those with cardiometabolic diseases. The MEDLINE, EMBASE, Cochrane database, OVID EBM Reviews, and clinicaltrials.gov databases were searched until February 2017. RCTs with a duration of ≥2 wk that evaluated the effects of anthocyanins on glycemic control, insulin sensitivity, and lipids as either primary or secondary outcomes were included. The Cochrane Risk of Bias tool was used to assess the study quality. Standardized mean differences (SMDs) were determined by random-effects models. Meta-regression, sensitivity, and subgroup analyses were performed to explore the influence of covariates on the overall effects. Thirty-two RCTs (1491 participants) were eligible for meta-analysis. Anthocyanins significantly reduced fasting glucose (SMD: -0.31; 95% CI: -0.59, -0.04; I² = 80.7%), 2-h postprandial glucose (SMD: -0.82; 95% CI: -1.49, -0.15; I² = 77.7), glycated hemoglobin (SMD: -0.65; 95% CI: -1.00, -0.29; I² = 72.7%), total cholesterol (SMD: -0.33; 95% CI: -0.62, -0.03; I² = 86.9%), and LDL (SMD: -0.35; 95% CI: -0.66, -0.05; I² = 85.2%). Sensitivity analyses showed that the overall effects remained similar by excluding the trials with a high or unclear risk of bias. The significant improvements in glycemic control and lipids support the benefits of anthocyanins in the prevention and management of cardiometabolic disease. Further well-designed RCTs are needed to evaluate the long-term effects of anthocyanins on metabolic profiles and to explore the optimal formula and dosage. The protocol for this review was registered at https://www.crd.york.ac.uk/PROSPERO/#index.php as CRD42016033210.

Optimized preparation of anthocyanin-rich extract from black rice and its effects on in vitro digestibility

The procedure for obtaining anthocyanin-enriched extracts from black rice was optimized by response surface methodology, and the effects of the optimized extract on in vitro starch digestibility were investigated in a wheat flour gel model. The experimental results were well-described by a polynomial multiple regression model (R² = 0.8812, p = 0.0546) with regard to anthocyanin content in anthocyanin-enriched extracts from black rice. The optimal conditions for obtaining anthocyanin-enriched extracts from black rice were 50.78% ethanol and 1 N HCl (0.60 mL), yielding a predicted anthocyanin content of 624.27 mg cyanidin 3 glucoside extract. The optimized anthocyanin-enriched extract was a stronger inhibitor of α-glucosidase than acarbose. Furthermore, the predicted glycemic index values of gels prepared with the optimized extract were significantly lower than that of wheat flour gel. These results indicate that the optimized extract suppressed starch hydrolysis by inhibiting digestive enzymes.

Dietary polyphenol intake and risk of type 2 diabetes in the Polish arm of the Health, Alcohol and Psychosocial factors in Eastern Europe (HAPIEE) study

This study aimed to test the association between dietary content of total and individual classes of polyphenols and incident cases of type 2 diabetes in Polish adults participating to the Health, Alcohol and Psychosocial factors In Eastern Europe study. At baseline, diet by 148-item FFQ and health information were collected from 5806 participants free of diabetes. Self-reported incident type 2 diabetes was ascertained at 2–4-year follow-up visit. OR and 95 % CI of type 2 diabetes comparing the various categories of polyphenol intake to the lowest one (reference category) and as 1 sd increase modelled as continuous variable were calculated by performing age-, energy-, and multivariate-adjusted logistic regression models. During the follow-up, 456 incident cases of type 2 diabetes occurred. When comparing extreme quartiles, intake of total polyphenol was inversely associated with the risk of type 2 diabetes (OR 0·43; 95 % CI 0·30, 0·61); 1 sd increase was associated with a reduced risk of diabetes (OR 0·68; 95 % CI 0·59, 0·79). Among the main classes of polyphenols, flavonoids, phenolic acids, and stilbenes were independent contributors to this association. Both subclasses of phenolic acids were associated with decreased risk of type 2 diabetes, whereas among subclasses of flavonoids, high intake of flavanols, flavanones, flavones and anthocyanins was significantly associated with decreased risk of type 2 diabetes. Total dietary polyphenols and some classes of dietary polyphenols were associated with lower risk of type 2 diabetes.

Anthocyanins from Black Chokeberry (Aroniamelanocarpa Elliot) Delayed Aging-Related Degenerative Changes of Brain

Aging is the greatest risk factor for most neurodegenerative diseases, which is associated with decreasing cognitive function and significantly affecting life quality in the elderly. Computational analysis suggested that 4 anthocyanins from chokeberry fruit increased Klotho (aging-suppressor) structural stability, so we hypothesized that chokeberry anthocyanins could antiaging. To explore the effects of anthocyanins treatment on brain aging, mice treated with 15 or 30 mg/kg anthocyanins by gavage and injected D-galactose accelerated aging per day. After 8 weeks, cognitive and noncognitive components of behavior were determined. Our studies showed that anthocyanins blocked age-associated cognitive decline and response capacity in senescence accelerated mice. Furthermore, mice treated with anthocyanins-supplemented showed better balance of redox systems (SOD, GSH-PX, and MDA) in all age tests. Three major monoamines were norepinephrine, dopamine, and 5-hydroxytryptamine, and their levels were significantly increased; the levels of inflammatory cytokines (COX2, TGF-β1, and IL-1) transcription and DNA damage were decreased significantly in brains of anthocyanins treated mice compared to aged models. The DNA damage signaling pathway was also regulated with anthocyanins. Our results suggested that anthocyanins was a potential approach for maintaining thinking and memory in aging mice, possibly by regulating the balance of redox system and reducing inflammation accumulation, and the most important factor was inhibiting DNA damage.

An LC-MS/MS method for quantitation of cyanidin-3-O-glucoside in rat plasma: Application to a comparative pharmacokinetic study in normal and streptozotocin-induced diabetic rats

A sensitive and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to determine cyanidin-3-O-glucoside (Cy-3G) in normal and streptozotocin-induced diabetic rat plasma. Chromatographic separation was carried out on a Zorbax SB-C₁₈ (50 × 4.6 mm, 5 μm) column and mass spectrometric analysis was performed using a Thermo Finnigan TSQ Quantum Ultra triple-quadrupole mass spectrometer coupled with an ESI source in the negative ion mode. Selected reaction monitoring mode was applied for quantification using target fragment ions m/z 447.3 → 285.2 for Cy-3G and m/z 463.0 → 300.1 for quercetin-3-O-glucoside (internal standard). The calibration curve was linear over the range 3.00-2700 ng/mL (r²  ≥ 0.99) with the lower limit of quantitation at 3.00 ng/mL. Intra- and inter-day precision was <14.5% and mean accuracy was from -11.5 to 13.6%. Stability testing showed that Cy-3G remained stable during the whole analytical procedure. After validation, the assay was successfully used to support a preclinical pharmacokinetic comparison of Cy-3G between normal and diabetic rats. Results indicated that diabetes mellitus significantly altered the in vivo pharmacokinetic characteristics of Cy-3G after oral administration in rats.

Gene-Diet Interactions in Type 2 Diabetes: The Chicken and Egg Debate

Consistent evidence from both experimental and human studies indicates that Type 2 diabetes mellitus (T2DM) is a complex disease resulting from the interaction of genetic, epigenetic, environmental, and lifestyle factors. Nutrients and dietary patterns are important environmental factors to consider in the prevention, development and treatment of this disease. Nutritional genomics focuses on the interaction between bioactive food components and the genome and includes studies of nutrigenetics, nutrigenomics and epigenetic modifications caused by nutrients. There is evidence supporting the existence of nutrient-gene and T2DM interactions coming from animal studies and family-based intervention studies. Moreover, many case-control, cohort, cross-sectional cohort studies and clinical trials have identified relationships between individual genetic load, diet and T2DM. Some of these studies were on a large scale. In addition, studies with animal models and human observational studies, in different countries over periods of time, support a causative relationship between adverse nutritional conditions during in utero development, persistent epigenetic changes and T2DM. This review provides comprehensive information on the current state of nutrient-gene interactions and their role in T2DM pathogenesis, the relationship between individual genetic load and diet, and the importance of epigenetic factors in influencing gene expression and defining the individual risk of T2DM.

Purple corn silk: A potential anti-obesity agent with inhibition on adipogenesis and induction on lipolysis and apoptosis in adipocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Corn silk or the stigma of Zea mays L. has traditionally been used in weight loss stimulation and treatment of cystitis, urinary infections and obesity. Purple corn silk, rich of polyphenolic substances, was reported on anti-diabetic and anti-obesity effect in animal studies. However, scientific evidence on mechanisms and targets of action of purple corn silk related to adipocyte life cycle has been limited.

AIM OF STUDY

To determine phytochemical compositions and investigate anti-obesity potential of the purple corn silk focusing on interruption of adipocyte life cycle; effect on pre-adipocyte proliferation, adipogenesis, adipocyte lipolysis, and apoptosis.

MATERIALS AND METHODS

The ethanolic purple corn silk extract (PCS) was prepared and investigated for phytochemical compositions by LC/MS/MS technique and anti-obesity potential using murine 3T3-L1 cell line. Using methyl thiazole tetrazolium (MTT) assay, the effects on pre-adipocytes and adipocyte viability and on pre-adipocytes proliferation at 24-, 48-, and 72-h incubation period were evaluated. In addition, anti-adipogenesis via inhibition on adipocyte differentiation and reduction of total lipid accumulation was evaluated using Oil Red O staining and spectrophotometric methods, respectively. The lipolysis effect was determined by measurement of glycerol released content using glycerol test kit after 48-h treatment of PCS to adipocytes. Apoptosis inductive effect was done by using 2-(4-Amidinophenyl)-6-indolecarbamidine dihydrochloride (DAPI) staining method.

RESULTS

The polyphenols including anthocyanins, quercetin and phenolic acids and derivatives were found as the major chemical compositions of the PCS. With multiple-stages interruption on the adipocyte life cycle, anti-obesity effect of PCS was interestingly demonstrated. When compared to the control, the PCS at concentration range between 250-1000 μg/mL showed anti-adipogenesis effect as expressing of significant inhibition on pre-adipocyte proliferation at all incubation period (43.52±5.28 - 75.51±9.09%) and significant decreasing of total lipid accumulation at concentration of 500μg/mL (80.22±6.58%) and 1000μg/mL (69.62±5.42%). Moreover, the PCS exhibited lipolysis and apoptosis inductive effect with dose dependent manner and significance at concentration of 1000μg/mL by increase of released glycerol content (173.88±6.13% of the control) and of nuclei condensing and apoptotic bodies (with relative apoptosis induction as 131.74±1.64% of the control).

CONCLUSION

Our data has evidenced the anti-obesity potential of PCS related interruption at multiple stages of adipocyte life cycle. Its potency was attributed to inhibition on adipocyte proliferation and adipogenesis as well as induction on lipolysis and apoptosis at high concentration. However, further in vivo investigation should be considered to insist the possibility in applications of PCS in prevention and treatment of obesity.

Eradication and Sensitization of Methicillin Resistant Staphylococcus aureus to Methicillin with Bioactive Extracts of Berry Pomace

The therapeutic roles of phenolic blueberry (Vaccinium corymbosum) and blackberry (Rubus fruticosus) pomace (commercial byproduct) extracts (BPE) and their mechanism of actions were evaluated against methicillin resistant Staphylococcus aureus (MRSA). Five major phenolic acids of BPE, e.g., protocatechuic, p. coumaric, vanillic, caffeic, and gallic acids, as well as crude BPE completely inhibited the growth of vegetative MRSA in vitro while BPE+methicillin significantly reduced MRSA biofilm formation on plastic surface. In addition, BPE restored the effectiveness of methicillin against MRSA by down-regulating the expression of methicillin resistance (mecA) and efflux pump (norA, norB, norC, mdeA, sdrM, and sepA) genes. Antibiogram with broth microdilution method showed that MIC of methicillin reduced from 512 μg/mL to 4 μg/mL when combined with only 200 μg Gallic Acid Equivalent (GAE)/mL of BPE. Significant reduction in MRSA adherence to and invasion into human skin keratinocyte Hek001 cells were also noticed in the presence of BPE. BPE induced anti-apoptosis and anti-autophagy pathways through overexpression of Bcl-2 gene and down-regulation of TRADD and Bax genes (inducers of apoptosis pathway) in Hek001 cells. In summary, novel and sustainable prophylactic therapy can be developed with BPE in combination with currently available antibiotics, especially methicillin, against skin and soft tissue infections with MRSA.

Health Benefits of Purple Corn (Zea mays L.) Phenolic Compounds

Purple corn (Zea mays L.), a grain with one of the deepest shades in the plant kingdom, has caught the attention of the food industry as it could serve as a source for alternatives to synthetic colorants. Also being rich in phenolic compounds with potential health-promoting properties, purple corn is becoming a rising star in the novel ingredients market. Although having been widely advertised as a "healthy" food, the available information on purple corn health benefits has not yet been well reviewed and summarized. In this review, we present compositional information focused on the potential functional phenolic compounds correlated to health-promoting effects. Studies evaluating potential health-benefitting properties, including in vitro tests, cell models, animal and human trials, are also discussed. This paper emphasizes research using purple corn, or its extracts, but some other plant sources with similar phenolic composition to purple corn are also mentioned. Dosage and toxicity of purple corn studies are also reviewed. Purple corn phenolic compounds have been shown in numerous studies to have potent antioxidant, anti-inflammatory, antimutagenic, anticarcinogenic, and anti-angiogenesis properties. They were also found to ameliorate lifestyle diseases, such as obesity, diabetes, hyperglycemia, hypertension, and cardiovascular diseases, based on their strong antioxidant power involving biochemical regulation amelioration. With promising evidence from cell and animal studies, this rich source of health-promoting compounds warrants additional attention to better understand its potential contributions to human health.

Effect of Elderberry (Sambucus nigra L.) Extract Supplementation in STZ-Induced Diabetic Rats Fed with a High-Fat Diet

Elderberry (Sambucus nigra L.) lipophilic and polar extract dietary supplementation effects were evaluated according to diabetes management indices, using an in vivo model. A research pipeline was constructed, that ranged from extract preparation, partial chemical characterization and toxicity evaluation, to examining the elderberry extract dietary supplementation effects on biofluid and tissues. Extracts toxicity was screened using an Aliivibrio fischeri bioluminescence model. A concentration of up to 60 mg/L was selected, and rat doses for oral supplementation were computed applying the interspecies correlation between A. fischeri and rats. Wistar type 2 diabetic rats, induced by streptozotocin (STZ), were fed a high-fat diet and supplemented for 4 weeks at doses of 190 and 350 mg/kg body weight/day of lipophilic and polar extract, respectively. As far as we know, lipophilic elderberry extract supplementation was assessed for the first time, while polar extract was administrated at higher doses and for a shorter period compared to previous studies, aiming to evaluate subacute supplementation effects. The polar extract modulated glucose metabolism by correcting hyperglycemia, while the lipophilic extract lowered insulin secretion. Both extracts lowered insulin resistance, without remarkable alterations to hematological indices, sera lipids and sera and tissular trace element homeostasis. In conclusion, elderberries are a potential source of bioactive compounds for formulations to be used as co-adjuvants in diabetes management.

Cyanidin-3-O-glucoside ameliorates palmitate-induced insulin resistance by modulating IRS-1 phosphorylation and release of endothelial derived vasoactive factors

Increased plasma levels of free fatty acids, including palmitic acid (PA), cause insulin resistance in endothelium characterized by a decreased synthesis of insulin-mediated vasodilator nitric oxide (NO), and by an increased production of the vasoconstrictor protein, endothelin-1. Several in vitro and in vivo studies suggest that anthocyanins, natural phenols commonly present in food and vegetables from Mediterranean Diet, exert significant cardiovascular health-promoting activities. These effects are possibly mediated by a positive regulation of the transcription factor Nrf2 and activation of cellular antioxidant and cytoprotective genes. The present study examined, at a molecular level, the effects of cyanidin-3-O-glucoside (C3G), a widely distributed anthocyanin, on PA-induced endothelial dysfunction and insulin resistance in human umbilical vein endothelial cells (HUVECs). Our results indicate that C3G pretreatment effectively reverses the effects of PA on PI3K/Akt axis, and restores eNOS expression and NO release, altered by PA. We observed that these effects were exerted by changes on the phosphorylation of IRS-1 on specific serine and tyrosine residues modulated by PA through the modulation of JNK and IKK activity. Furthermore, silencing Nrf2 transcripts demonstrated that the protective effects of C3G are directly related to the activation of Nrf2.

Potential role of cyanidin 3-glucoside (C3G) in diabetic cardiomyopathy in diabetic rats: An in vivo approach

The present study aimed to evaluate the importance of cyanidin 3-glucoside (C3G) of diabetic cardiomyopathy in diabetic rats. The rats were induced with diabetic using streptozotocin and total triglyceride (TG) and total cholesterol (TC) were determined. The range of myocardial enzymes such as aspartate aminotransferase (AST), creatine kinase (CK) and lactate dehydrogenase (LD) were also estimated, further, the Immuno histochemical analysis and western blot investigation were determined for the actual activity of C3G. Results indicated that the marker enzymes such as CK, LD and AST were significantly (P < 0.05) increased in STZ administered rats (DM group), while the levels of these elevated marker enzymes of cardiac injury significantly (P < 0.05) declined in the DM + C3G group, as compared to the diabetic group of rats. Additionally, a decrease in the level of TNF-alpha and interleukin-6, was noticed in the C3G treated group as compared to diabetic group. Finally, blotting analysis clearly confirmed that theC3G treatment resulted to higher level response of Bcl-2 and lower level response of caspase-3 and BAX. In conclusion, C3G a natural antioxidant may prevent cardiovascular complications by ameliorating oxidative damage, inflammation, metabolic dysfunctions and apoptosis pathways in type 2 diabetes.

Cyanidin-3-glucoside attenuates angiotensin II-induced oxidative stress and inflammation in vascular endothelial cells

Angiotensin II (Ang II) causes oxidative stress and vascular inflammation, leading to vascular endothelial cell dysfunction, and is associated with the development of inflammatory cardiovascular diseases such as atherosclerosis. Therefore, interventions of oxidative stress and inflammation may contribute to the reduction of cardiovascular diseases. Cyanidin-3-glucoside (C3G) plays a role in the prevention of oxidative damage in several diseases. Here, we investigated the effect of C3G on Ang II-induced oxidative stress and vascular inflammation in human endothelial cells (EA.hy926). C3G dose-dependently suppressed the free radicals and inhibited the nuclear factor-kappa B (NF-κB) signaling pathway by protecting the degradation of inhibitor of kappa B-alpha (IκB-α), inhibiting the expression and translocation of NF-κB into the nucleus through the down-regulation of NF-κB p65 and reducing the expression of inducible nitric oxide synthase (iNOS). Pretreatment with C3G not only prohibited the NF-κB signaling pathway but also promoted the activity of the nuclear erythroid-related factor 2 (Nrf2) signaling pathway through the upregulation of endogenous antioxidant enzymes. Particularly, we observed that C3G significantly enhanced the production of superoxide dismutase (SOD) and induced the expression of heme oxygenase (HO-1). Our findings confirm that C3G can protect against vascular endothelial cell inflammation induced by AngII. C3G may represent a promising dietary supplement for the prevention of inflammation, thereby decreasing the risk for the development of atherosclerosis.

Whole Grains in Amelioration of Metabolic Derangements

Daily diet influences whole body metabolism, and intricately linked to the prevention or progression of metabolic diseases including obesity, diabetes and cardiovascular diseases. Several epidemiological and large scale studies have shown that diets enriched with whole grains improves metabolic function and protect from the development of metabolic diseases. Direct impact of whole grain diet can be mediated on several levels of metabolic functions i.e. reduced glycemic index, improved fat oxidation potential, increased cholesterol clearance or decreased cholesterol biosynthesis and modulation of gut microbiome. In this article we reviewed several studies indicating the beneficial effects of whole grain diets on metabolic functions, as well as discussed the potential active phytochemicals present in these whole grain foods to contribute in modulation of metabolic function in our body.

Mulberry anthocyanin extract regulates glucose metabolism by promotion of glycogen synthesis and reduction of gluconeogenesis in human HepG2 cells

Mulberry has been demonstrated to possess important biological activities such as antioxidation and antiinflammation. However, research on the ability of mulberry for diabetes improvement mainly focuses on the leaves and less on the fruit. This study showed that a mulberry anthocyanin extract (MAE) had a significant effect on increasing the glucose consumption in HepG2 cells. The MAE enhanced the glycogen content and suppressed levels of glucose production. The enzyme activities of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) were decreased in HepG2 cells after MAE treatment due to PPARγ coactivator 1α (PGC-1α) and forkhead box protein O1 (FOXO1) inhibition. Moreover, the phosphorylation of protein kinase B (AKT) and glycogen synthase kinase-3β (GSK-3β) was increased by the MAE, leading to an expression enhancement of glycogen synthase 2 (GYS2). And this effect was blocked by the phosphoinositide 3-kinase (PI3K) inhibitor LY294002. In summary, our results suggested that the MAE regulates glucose metabolism by activating the PI3K/AKT pathway that relates to glycogen synthesis as well as through the inhibition of key molecules that promote gluconeogenesis.

Wild blueberry consumption attenuates local inflammation in the perivascular adipose tissue of obese Zucker rats

Perivascular adipose tissue (PVAT) has been shown to play important roles in regulating vascular tone and linking local and systemic vascular inflammation. We examined the impact of PVAT on phenylephrine-mediated vasoconstriction in the aorta of obese Zucker rats (OZR) and their lean littermates (LZR) by comparing aortic rings with or without PVAT. Subsequently we placed OZR and LZR on a control (C) or an 8% wild blueberry (WB) diet and evaluated the effect of WB consumption on such response. PVAT-released adipokine concentrations were also measured as a function of WB diet. Maximal constrictor force (Fmax) in aortic rings without PVAT was significantly lower in OZR-C compared with LZR-C (0.41 ± 0.05 and 0.71 ± 0.06 g, respectively). Following WB diet, Fmax significantly increased in OZR (0.54 ± 0.06 g). In aortas with intact PVAT, Fmax was significantly lower in all groups (0.31 ± 0.06 OZR-C, 0.30 ± 0.05 OZR-WB, 0.29 ± 0.03 LZR-C, and 0.30 ± 0.04 g LZR-WB), but no difference was observed between treatments. PVAT concentrations of monocyte chemoactractant protein 1 (MCP-1), tumor necrosis factor alpha, and adiponectin were significantly higher in OZR compared with LZR (+102%, +108%, and +45%, respectively). Following WB diet, PVAT concentrations of interleukin-8 were significantly lower in both OZR (-37%) and LZR (-30%), while adiponectin concentrations significantly increased in both OZR (+11%) and LZR (+16%). MCP-1 concentrations significantly decreased (-31%) in the PVAT of OZR with the WB diet. WB consumption appears to attenuate local inflammation in PVAT, which may impact systemic vascular inflammation and endothelial function.

Synergistic effect of atorvastatin and cyanidin-3-glucoside against angiotensin II-mediated vascular smooth muscle cell proliferation and migration through MAPK and PI3K/Akt pathways

This study aimed to investigate the mechanism of cyanidin-3-glucoside (C3G) in synergy with atorvastatin, even when it is used in low concentrations. Human aortic smooth muscle cells (HASMCs) were used to verify the synergistic mechanism of atorvastatin and C3G against angiotensin II-induced proliferation and migration. BrdU incorporation assay was used to evaluate cell proliferation. Wound healing and Boyden chamber assays were used to investigate cell migration. The cell cycle was examined using flow cytometry. The results revealed that atorvastatin and C3G exhibit a synergistic effect in ameliorating HASMC proliferation and migration by enhancing cell cycle arrest. In addition, these effects also decreased mitogen-activated protein kinase (MAPK) activity by attenuating the expression of phospho-p38, phospho-extracellular signaling-regulated kinase 1/2, and phospho-c-Jun N-terminal kinase. Furthermore, the combination of atorvastatin and C3G modulated the PI3K/Akt pathway and upregulated p21Cip1, which was associated with decreases in cyclin D1 and phospho-retinoblastoma expressions. The synergistic effect of atorvastatin and C3G induced anti-proliferation and anti-migration through MAPK and PI3K/Akt pathways mediated by AT1R. These results suggest that the synergistic effect of atorvastatin and C3G may be an alternative therapy for atherosclerosis patients.

Purification of Flavonoids from Chinese Bayberry (Morella rubra Sieb. et Zucc.) Fruit Extracts and α-Glucosidase Inhibitory Activities of Different Fractionations

Chinese bayberry (Morella rubra Sieb. et Zucc.) fruit have a diverse flavonoid composition responsible for the various medicinal activities, including anti-diabetes. In the present study, efficient simultaneous purification of four flavonoid glycosides, i.e., cyanidin-3-O-glucoside (1), myricetin-3-O-rhamnoside (2), quercetin-3-O-galactoside (3), quercetin-3-O-rhamnoside (4), from Chinese bayberry pulp was established by the combination of solid phase extract (SPE) by C18 Sep-Pak^® cartridge column chromatography and semi-preparative HPLC (Prep-HPLC), which was followed by HPLC and LC-MS identification. The purified flavonoid glycosides, as well as different fractions of fruit extracts of six bayberry cultivars, were investigated for α-glucosidase inhibitory activities. The flavonol extracts (50% methanol elution fraction) of six cultivars showed strong α-glucosidase inhibitory activities (IC₅₀ = 15.4–69.5 μg/mL), which were higher than that of positive control acarbose (IC₅₀ = 383.2 μg/mL). Four purified compounds 1–4 exerted α-glucosidase inhibitory activities, with IC₅₀ values of 1444.3 μg/mL, 418.8 μg/mL, 556.4 μg/mL, and 491.8 μg/mL, respectively. Such results may provide important evidence for the potential anti-diabetic activity of different cultivars of Chinese bayberry fruit and the possible bioactive compounds involved.