Chemopreventive effect of troxerutin against hydrogen peroxide-induced oxidative stress in human leukocytes through modulation of glutathione-dependent enzymes.

Troxerutin is a natural flavonoid present abundantly in tea, coffee, olives, wheat, and a variety of fruits and vegetables. Due to its diverse pharmacological properties, this flavonoid has aroused interest for treatment of various diseases, and consequently prompted investigation into its toxicological characteristics. The aim of this study was to evaluate the genotoxic and mutagenic effects and chemoprotective activity attributed to troxerutin using human peripheral blood leukocytes (PBLs) through several well-established experimental protocols based upon different parameters. Data demonstrated that troxerutin (100 to 1000 µM) induced no marked cytotoxic effect on PBLs after 24 hr, and did not produce strand breaks and mutagenicity. Regarding chemoprevention, this flavonoid attenuated cytotoxicity, genotoxicity, and mutagenicity initiated by hydrogen peroxide (H2O2) in human PBLs. Further, troxerutin demonstrated no marked cytotoxic effect on PBLs and exerted a protective effect against oxidative stress induced by H2O2 through modulation of GSH-dependent enzymes.

Anticancer and cytotoxic effects of troxerutin on HeLa cell line: an in-vitro model of cervical cancer.

Cervical cancer is one of the grave uterine tumors which leads to death in women worldwide. Troxerutin (TRX) as a bioflavonoid compound has many pharmacological effects such as anti-neoplastic, radioprotective, and anti-cancer. The present study was designed to examine the cytotoxic effect of TRX on human HeLa tumor cells. Human HeLa cells were cultured and treated with different doses of TRX (20-640 mg/ml) to evaluate the effective half-maximal inhibitory concentration (IC50) after 24 h. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test was used for cell proliferation assay. Also, the Bax, Bcl-2, cleaved caspase-3, and tumor necrosis factor-α (TNF-α) protein expression levels were detected with immunoblotting analysis. The malondialdehyde (MDA) concentration, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity levels were measured via their commercial kits. Data were analyzed using one-way ANOVA. The result showed that TRX at 320 mg/ml concentration (IC50) has a growth inhibitory effect against HeLa cells at 24 h treatment (P ˂ 0.01). Moreover, it increased the MDA concentration and also decreased the GPx and SOD activity levels at 320 mg/ml concentration versus control (P < 0.001). Also, TRX significantly up-regulated the Bax, cleaved caspase-3 and TNF-α proteins expression levels (P  < 0.01) and down-regulated the Bcl-2 protein expression in HeLa tumor cells at 320 mg/ml concentration compared to control (P < 0.05). Our study showed that 24 h of treatment with TRX (320 mg/ml) has apoptotic and growth inhibitory effects against HeLa cells. It can induce inflammation (at least via up-regulating the TNF-α protein expression) and oxidative stress in human HeLa cells.

Can troxerutin pretreatment prevent testicular complications in prepubertal diabetic male rats?

OBJECTIVE: The vast majority of type 1 diabetes leads to a higher prevalence of reproductive system's impairments. Troxerutin has attracted much attention owing to its favorable properties, including antihyperglycemic, anti-inflammatory, and antiapoptotic effects. This investigation was proposed to evaluate whether pretreatment with troxerutin could prevent apoptosis-induced testicular disorders in prepubertal diabetic rats. METHODS: Fifty prepubertal male Wistar rats were randomly allocated into five groups: control (C), troxerutin (TX), diabetic (D), diabetic+troxerutin (DTX), and diabetic+insulin (DI). Diabetes was induced by 55 mg/kg of streptozotocin applied intraperitoneally. In TX and DTX groups, 150 mg/kg troxerutin was administered by oral gavage. Diabetic rats in DI group received 2-4 U NPH insulin subcutaneously. Troxerutin and insulin treatments were begun immediately on the day of diabetes confirmation. After 30 days, the testicular lipid peroxidation and antioxidant activity, apoptosis process, and stereology as well as serum glucose and insulin levels were assessed. RESULTS: The results showed that diabetes caused a significant increase in the blood glucose, the number of TUNEL positive cells and tubules, and the malondialdehyde level as well as a significant decrease in serum insulin level compared to controls. The stereological analysis also revealed various alterations in diabetic rats compared to controls. Troxerutin treatment improved these alterations compared to the diabetic group. CONCLUSION: Troxerutin-pretreatment may play an essential role in the management of the type-1 diabetes-induced testicular disorders by decreasing blood glucose and modulating apoptosis.

Anti-inflammatory effects of troxerutin are mediated through elastase inhibition.

CONTEXT: Obesity is a chronic low-grade inflammatory state associated with immune cell infiltration into the adipose tissue (AT). We hypothesize that the anti-obesity and anti-inflammatory effects of troxerutin (TX) are mediated through inhibition of elastase. OBJECTIVE: To determine the inhibitory effect of TX on elastase in vitro and in tumor necrosis factor alpha (TNFα) induced 3T3-L1 adipocytes and the molecular interaction of TX with human neutrophil elastase (HNE). MATERIALS AND METHODS: Differentiated 3T3-L1 adipocytes were pretreated with TX, elastatinal (ELAS) or sodium salicylate (SAL) before exposure to TNFα. Lipid accumulation, reactive oxygen species (ROS) generation and oxidant-antioxidant balance were examined. The mRNA and protein expression of TNFα, interleukin-6, monocyte chemoattractant protein-1, adiponectin, leptin, resistin, chemerin, and elastase were analyzed. Elastase inhibition by TX and ELAS in a cell free system and docking studies for HNE with TX and ELAS were performed. RESULTS: TX, ELAS or SAL pretreatment had lowered lipid droplets formation and TG content. TX suppressed ROS generation, oxidative stress and improved antioxidant status. The expression of inflammatory cytokines and elastase was downregulated while that of adiponectin was upregulated by TX. The concentration required to produce 50% inhibition in vitro (IC50) was 11.5 µM for TX and 16.9 µM for ELAS. TX showed hydrogen bonding and hydrophobic interactions with elastase. DISCUSSION: TNFα induces inflammation of 3T3-L1 cells through elastase activation. TX inhibits elastase activity, downregulates expression and binds with elastase. CONCLUSION: The antioxidant and anti-inflammatory activities of TX in AT could be of relevance in the management of obesity.

Troxerutin attenuates myocardial cell apoptosis following myocardial ischemia-reperfusion injury through inhibition of miR-146a-5p expression.

The aim of the current study was to investigate the effects and the underlying mechanisms of troxerutin on myocardial cell apoptosis during ischemia-reperfusion (I/R) injury. Hypoxia/reoxygenation (H/R) model in neonatal rat cardiomyocytes, and I/R model in rats, were established following troxerutin preconditioning. The quantitative real-time polymerase chain reaction analysis was performed to examine the messenger RNA miR-146a-5p expression in cardiomyocytes and myocardial tissues. Hemodynamic parameters and serum creatine kinase, lactate dehydrogenase, tumor necrosis factor-α, and interleukin-10 were evaluated. Infarct size was examined by 2,3,5-triphenyltetrazolium chloride staining. Besides, myocardial apoptosis was detected by terminal deoxynucleotidyl transferase (dUTP) nick end labeling (TUNEL) assay. Western blot analysis was performed to determine the protein levels of caspase-3, Bax, and Bcl-2. The results showed that, troxerutin decreased rat cardiomyocyte apoptosis during H/R injury. Furthermore, the antiapoptotic effect of troxerutin against I/R injury was mediated by miR-146a-5p downregulation. In vivo experiments suggested that troxerutin alleviated myocardial I/R injury in rats via inhibition of miR-146a-5p. In conclusion, troxerutin exerted cardioprotective effects during I/R injury by downregulating miR-146a-5p.

Troxerutin exerts neuroprotection against lipopolysaccharide (LPS) induced oxidative stress and neuroinflammation through targeting SIRT1/SIRT3 signaling pathway.

This study was conducted to clarify the potential mechanisms of Troxerutin neuroprotection against Lipopolysaccharide (LPS) induced oxidative stress and neuroinflammation through targeting the SIRT1/SIRT3 signaling pathway. To establish a model, a single dose of LPS (500µg/kg body weight) was injected to male Wistar rats intraperitoneally. Troxerutin (100 mg/kg body weight) was injected intraperitoneally for 5 days after induction of the model. Cognitive and behavioral evaluations were performed using Y-maze, single-trial passive avoidance, and novel object recognition tests. The expression of inflammatory mediators, SIRT1/SIRT3, and P53 was measured using the ELISA assay. Likewise, the expression levels of SIRT1/SIRT3 and NF-κB were determined using Western blot assay. Brain acetyl-cholinesterase activity was determined by utilizing the method of Ellman. Reactive oxygen species (ROS) was detected using Fluorescent probe 2, 7-dichlorofluorescein diacetate (DCFH-DA). Furthermore, malondialdehyde (MDA) levels were determined. A single intraperitoneal injection of LPS was led to ROS production, acute neuroinflammation, apoptotic cell death, and inactivation of the SIRT1/SIRT3 signaling pathway. Likewise, ELISA assay demonstrated that post-treatment with Troxerutin considerably suppressed LPS-induced acute neuroinflammation, oxidative stress, apoptosis and subsequently memory impairments by targeting SIRT1/SIRT3 signaling pathway. Western blot assay confirmed ELISA results about SIRT1/SIRT3 and NF-κB proteins. These results suggest that Troxerutin can be a suitable candidate to treat neuroinflammation caused by neurodegenerative disorders.

Combining an in silico approach with an animal experiment to investigate the protective effect of troxerutin for treating acute lung injury.

BACKGROUND: Troxerutin (TRX), a naturally occurring flavonoid in various fruits, has been reported to exhibit numerous pharmacological and biological activities in vitro and in vivo. However, the molecular mechanisms underlying TRX as a treatment for disease are poorly understood. METHODS: Using pharmacophore mapping and inverse docking, a set of potential TRX target proteins that have been associated with multiple forms of diseases was obtained. Bioinformatic analyses were performed using the Enrichr and STRING servers to analyse the related biological processes and protein-protein networks. Furthermore, we investigated the potential protective effect of TRX against lipopolysaccharide-induced acute lung injury (ALI) using a mouse model. Morphological changes in the lungs were assessed using haematoxylin and eosin staining. Inflammatory cytokines, tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), IL-6 and IL-10 were investigated using ELISA. Activation of MAPK and NF-κB was detected using western blotting. RESULTS: Our network pharmacology analysis revealed the existence of multiple TRX-related chemical-target interactions and the related biological processes. We found that pretreatment with TRX protected against histological changes and obviously regulated the inflammatory cell counts and inflammatory cytokine levels in bronchoalveolar lavage fluid. Based on bioinformatic and western blot analyses, TRX may exert a protective effect against ALI by inhibiting MAPK and NF-κB signalling. CONCLUSIONS: TRX can ameliorate pulmonary injury by inhibiting the MAPK and NF-κB signalling pathways and has a potential protective effect against ALI. This study may be helpful for understanding the mechanisms underlying TRX action and for discovering new drugs from plants for the treatment of ALI.

Troxerutin with copper generates oxidative stress in cancer cells: Its possible chemotherapeutic mechanism against hepatocellular carcinoma.

Troxerutin (TXER) a rutin derivative is known for its anticancer effect against hepatocellular carcinoma (HCC). As part of large study, recently we have shown TXER interact with genetic material and its anti-mutagenic property. In the present study we have explored its possible mode of action in HCC. Since TXER alone did not show significant anticancer effect on Huh-7 cells, in vitro biochemical assays were performed for determining anticancer efficacy of TXER + metal complex using transition metals such as Cu, Zn, and Fe. The anticancer efficacy of TXER + Cu on Huh-7 cells were evaluated using MTT assay, DCFDA, JC-1 staining, comet assay, cell cycle analysis, immunocytochemistry, and Western blotting. Non-toxic nature of TXER was analyzed on primary rat hepatocytes. The in vivo efficacy of TXER was tested in N-nitrosodiethylamine initiated and γ-benzene hexachloride and partial hepatectomy promoted rat liver cancer. Liver markers, transition metal levels, histopathological examination, and expression levels of GST-P, 8-OHdG and Ki-67 were studied to assess the in vivo anticancer effect of TXER. We observed that TXER + Cu induced extensive cellular death on Huh-7 cells through generating free radicals and did not possess any toxic effect on normal hepatocytes. The in vivo studies revealed that TXER possess significant anti-cancer effect as assessed through improved liver markers and suppressed GST-P, 8-OHdG, and Ki-67 expression. TXER treatment reduced the hepatic Cu level in cancer bearing animals. Current study brings the putative mechanism involved in anti-cancer effect of TXER, further it will help to formulate phytoconstituents coupled anti-cancer drug for effective treatment of HCC.

Troxerutin Protects Against Myocardial Ischemia/Reperfusion Injury Via Pi3k/Akt Pathway in Rats.

BACKGROUND/AIMS: Troxerutin, also known as vitamin P4, has been commonly used in the treatment of chronic venous insufficiency (CVI) disease. However, its effect on in vivo myocardial ischemia/reperfusion (I/R) injury, a model that closely mimics acute myocardial infarction in humans, is still unknown. METHODS: The myocardial I/R injury rat model was created with troxerutin preconditioning. Myocardial infarct size was evaluated by the Evans blue-TTC method. Hemodynamic parameters, including the heart rate (HR), left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), maximal rate of rise in blood pressure in the ventricular chamber (+dp/dt max), and maximal rate of decline in blood pressure in the ventricular chamber (-dp/dt max) were monitored. Serum TNF-α and IL-10 were determined by ELISA kit. Cell apoptosis was detected by MTT method. RESULTS: Troxerutin preconditioning significantly reduced myocardial infarct size, improved cardiac function, and decreased the levels of creatine kinase (CK), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) in the I/R injury rat model. The serum and mRNA levels of TNF-α and IL-10 as well as some apoptosis markers (Bax, Caspase 3) also decreased. Moreover, troxerutin pretreatment markedly increased the phosphorylation of Akt, and blocking PI3K activity by LY294002 abolished the protective effect of troxerutin on I/R injury. CONCLUSION: Troxerutin preconditioning protected against myocardial I/R injury via the PI3K/Akt pathway.

The in vivo antineoplastic and therapeutic efficacy of troxerutin on rat preneoplastic liver: biochemical, histological and cellular aspects.

PURPOSE: Troxerutin (TXER), a trihydroxyethylated derivative of the natural bioflavonoid rutin, abundantly found in tea, various fruits and vegetables, is known to exhibit ample pharmacological properties. In the present investigation, we examined the antineoplastic, therapeutic efficacy and furthermore the possible mechanisms of action of TXER against NAFLD/NASH progression to hepatocarcinogenesis. METHODS: The effect of TXER (12.5, 25 or 50 mg/kg b.w/day) was evaluated on the nitrosodiethylamine (NDEA) model of hepatocarcinogenesis in rats, after 16 weeks of oral treatment, with special focus on liver specific enzymes, xenobiotic metabolizing enzymes, antioxidant status, lipid peroxidation profile, DNA damage, fibrosis, cell proliferation and inflammatory status. RESULTS: Administration of TXER to hepatocellular carcinoma-bearing rats restored the enzyme activities and the hepatic architecture. Furthermore, TXER significantly curtailed NDEA-induced DNA damage, cell proliferation, inflammation, fibrosis and hepatic hyperplasia. CONCLUSION: This study provides the evidence that troxerutin exerts a significant therapeutic effect against liver cancer by modulating liver function enzymes, xenobiotic enzymes, oxidative damage, inhibiting cell proliferation, suppressing inflammatory response and induction of apoptosis.

Short-term effects of troxerutin (vitamin P4) on muscle fatigue and gene expression of Bcl-2 and Bax in the hepatic tissue of rats.

In the current study, the effects of troxerutin (TRX) on muscle fatigue and gene expression of Bcl-2 and Bax in the hepatic tissue of rats was investigated. Forty male Wistar rats were randomly divided into 4 groups and designated as control and TRX treatment at 75 (TRX75), 150 (TRX150), and 300 mg/kg per day (TRX300). The treated groups and control group received TRX and water orally for 7 days. After an exhaustive swimming test on the 7th day, all animals were euthanized immediately and several biochemical parameters related to fatigue and gene expression of Bcl-2 and Bax in the hepatic tissue were measured. Our results showed that the exhaustion swimming time in the TRX300 groups significantly increased 1.2-fold compared with the control group (P < 0.001). TRX300 significantly reduced ALT (P < 0.05) activity and increased liver SOD activity compared with the control group (P < 0.01). Additionally, TRX significantly reduced the liver mRNA expressions of Bax (P < 0.001) and increased the Bcl-2/Bax ratio (P < 0.001) compared with the control group. Based on our data, TRX possesses anti-apoptotic and hepatoprotective action following exhaustive swimming exercise.

Troxerutin attenuates diet-induced oxidative stress, impairment of mitochondrial biogenesis and respiratory chain complexes in mice heart.

Mitochondrial abnormality is thought to play a key role in cardiac disease originating from the metabolic syndrome (MS). We evaluated the effect of troxerutin (TX), a semi-synthetic derivative of the natural bioflavanoid rutin, on the respiratory chain complex activity, oxidative stress, mitochondrial biogenesis and dynamics in heart of high fat, high fructose diet (HFFD) -induced mouse model of MS. Adult male Mus musculus mice of body weight 25-30 g were fed either control diet or HFFD for 60 days. Mice from each dietary regimen were divided into two groups on the 16th day and were treated or untreated with TX (150 mg/kg body weight [bw], per oral) for the next 45 days. At the end of experimental period, respiratory chain complex activity, uncoupling proteins (UCP)-2 and -3, mtDNA content, mitochondrial biogenesis and dynamics, oxidative stress markers and reactive oxygen species (ROS) generation were analyzed. Reduced mtDNA abundance with alterations in the expression of genes related to mitochondrial biogenesis and fission and fusion processes were observed in HFFD-fed mice. Disorganized and smaller mitochondria, reduction in complexes I, III and IV activities (by about 55%) and protein levels of UCP-2 (52%) and UCP-3 (46%) were noted in these mice. TX administration suppressed oxidative stress, improved the oxidative capacity and biogenesis and restored fission/fusion imbalance in the cardiac mitochondria of HFFD-fed mice. TX protects the myocardium by modulating the putative molecules of mitochondrial biogenesis and dynamics and by its anti-oxidant function in a mouse model of MS.

Troxerutin Attenuates Enhancement of Hepatic Gluconeogenesis by Inhibiting NOD Activation-Mediated Inflammation in High-Fat Diet-Treated Mice.

Recent evidence suggests that troxerutin, a trihydroxyethylated derivative of natural bioflavonoid rutin, exhibits beneficial effects on diabetes-related symptoms. Here we investigated the effects of troxerutin on the enhancement of hepatic gluconeogenesis in high-fat diet (HFD)-treated mice and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + Troxerutin group, and Troxerutin group. Troxerutin was treated by daily oral administration at doses of 150 mg/kg/day for 20 weeks. Tauroursodeoxycholic acid (TUDCA) was used to inhibit endoplasmic reticulum stress (ER stress). Our results showed that troxerutin effectively improved obesity and related metabolic parameters, and liver injuries in HFD-treated mouse. Furthermore, troxerutin significantly attenuated enhancement of hepatic gluconeogenesis in HFD-fed mouse. Moreover, troxerutin notably suppressed nuclear factor-κB (NF-κB) p65 transcriptional activation and release of inflammatory cytokines in HFD-treated mouse livers. Mechanismly, troxerutin dramatically decreased Nucleotide oligomerization domain (NOD) expression, as well as interaction between NOD1/2 with interacting protein-2 (RIP2), by abating oxidative stress-induced ER stress in HFD-treated mouse livers, which was confirmed by TUDCA treatment. These improvement effects of troxerutin on hepatic glucose disorders might be mediated by its anti-obesity effect. In conclusion, troxerutin markedly diminished HFD-induced enhancement of hepatic gluconeogenesis via its inhibitory effects on ER stress-mediated NOD activation and consequent inflammation, which might be mediated by its anti-obesity effect.

The flavonoid monoHER promotes the adaption to oxidative stress during the onset of NAFLD.

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease. An evidence-based pharmacological treatment for NAFLD is still lacking, but flavonoids have shown therapeutic potential. The present study was designed to investigate the effect of the flavonoid monoHER on the onset of NAFLD in Ldlr(-/-) mice on a high-fat and high-cholesterol diet. The focus was put on the effect on oxidative stress as well as the adaptive response. Wild type mice served as a control and the effect of monoHER was compared to that of a placebo. In the Ldlr(-/-) group, monoHER provided only a mild protection against oxidative stress. In the placebo Ldlr(-/-) group an adaptive response elicited by the NRF2 antioxidant defense system was observed, evidenced by a higher HO-1 and Gpx3 gene expression, as well as an increased redox status, evidenced by the higher GSH/GSSG ratio. In the monoHER treated Ldlr(-/-) group both the adaptive response as well as the increase in redox status tended to be higher, although this did not reach significance on a group level. Unexpectedly, a strong within animal relationship was found that links a high adaptive response to a low redox status in the monoHER Ldlr(-/-) group. This correlation was absent in the placebo and wild type group. The concept that emerges is that a thiol-reactive oxidation product of monoHER, formed during oxidative stress, selectively induces the NRF2 pathway and enforces the endogenous antioxidant shield, to provide protection against NAFLD.

Troxerutin reverses fibrotic changes in the myocardium of high-fat high-fructose diet-fed mice.

A previous study from our laboratory showed that troxerutin (TX) provides cardioprotection by mitigating lipid abnormalities in a high-fat high-fructose diet (HFFD)-fed mice model of metabolic syndrome (MS). The present study aims to investigate the reversal effect of TX on the fibrogenic changes in the myocardium of HFFD-fed mice. Adult male Mus musculus mice were grouped into four and fed either control diet or HFFD for 60 days. Each group was divided into two, and the mice were either treated or untreated with TX (150 mg/kg bw, p.o) from the 16th day. HFFD-fed mice showed marked changes in the electrocardiographic data. Increased levels of myocardial superoxide, p22phox subunit of NADPH oxidase, transforming growth factor (TGF), smooth muscle actin (α-SMA), and matrix metalloproteinases (MMPs)-9 and -2, and decreased levels of tissue inhibitors of MMPs-1 and -2 were observed. Furthermore, degradation products of troponin I and myosin light chain-1 were observed in the myocardium by immunoblotting. Rise in collagen was observed by hydroxyproline assay, while fibrotic changes were noticed by histology and Western blotting. Hypertrophy of cardiomyocytes and myocardial calcium accumulation were also observed in HFFD-fed mice. TX treatment exerted cardioprotective and anti-fibrotic effects in HFFD-fed mice by improving cardiac contractile function, reducing superoxide production and by favorably modifying the fibrosis markers. These findings suggest that TX could be cardioprotective through its antioxidant and antifibrogenic actions. This new finding could pave way for translation studies to human MS.

Troxerutin counteracts domoic acid-induced memory deficits in mice by inhibiting CCAAT/enhancer binding protein ß-mediated inflammatory response and oxidative stress.

The C/EBP ß is a basic leucine zipper transcription factor that regulates a variety of biological processes, including metabolism, cell proliferation and differentiation, and immune response. Recent findings show that C/EBP ß-induced inflammatory responses mediate kainic acid-triggered excitotoxic brain injury. In this article, we show that protein kinase C ζ enhances K-ras expression and subsequently activates the Raf/MEK/ERK1/2 pathway in the hippocampus of domoic acid (DA)-treated mice, which promotes C/EBP ß expression and induces inflammatory responses. Elevated production of TNF-α impairs mitochondrial function and increases the levels of reactive oxygen species by IκB kinase ß/NF-κB signaling. The aforementioned inflammation and oxidative stress lead to memory deficits in DA-treated mice. However, troxerutin inhibits cyclin-dependent kinase 1 expression, enhances type 1 protein phosphatase α dephosphorylation, and abolishes MEK/ERK1/2/C/EBP ß activation, which subsequently reverses the memory impairment observed in the DA-treated mice. Thus, troxerutin is recommended as a potential candidate for the prevention and therapeutic treatment of cognitive deficits resulting from excitotoxic brain damage and other brain disorders.

Troxerutin suppresses lipid abnormalities in the heart of high-fat-high-fructose diet-fed mice.

The reversal effect of troxerutin (TX) on obesity, insulin resistance, lipid accumulation, oxidative damage, and hypertension induced in the high-fat-high-fructose diet (HFFD)-fed mice model of metabolic syndrome was investigated. Adult male Mus musculus mice of body weight 25-30 g were fed either control diet or HFFD. Each group was divided into two and treated or untreated with TX (150 mg/kg bw, p.o.) from the 16th day. Assays were done in plasma and heart after 30 and 60 days of the experimental period. Significant increase in the levels of glucose and insulin, blood pressure (BP), and oxidative stress were observed after 30 days of HFFD feeding as compared to control. Animals fed HFFD for 60 days developed more severe changes in the above parameters compared to those fed for 30 days. Hearts of HFFD-fed mice registered downregulation of peroxisome proliferator-activated receptor-α and peroxisome proliferator-activated receptor gamma coactivator-1α, carnitine palmitoyl transferse-1b and AMP-activated protein kinase; and upregulation of cluster of differentiation 36, fatty acid-binding protein-1, and sterol regulatory element-binding protein-1c after 60 days. TX administration restricted obesity (as seen by Lee's index); improved whole body insulin sensitivity; reduced BP, lipid accumulation, and oxidative damage; upregulated fatty acid (FA) oxidation; and downregulated FA transport and lipogenesis. Histology of heart revealed that TX diminishes inflammatory cell infiltration and fatty degeneration in HFFD-fed mice. The antioxidant property of TX and its ability to influence lipid regulatory genes could be the underlying mechanisms for its beneficial effects.

Effect of troxerutin on insulin signaling molecules in the gastrocnemius muscle of high fat and sucrose-induced type-2 diabetic adult male rat.

Troxerutin is a trihydroxyethylated derivative of the flavonoid, rutin. It has been reported to possess the hepatoprotective, nephroprotective, antioxidant, anti-inflammatory, and antihyperlipidemic activities. Troxerutin treatment reduced the blood glucose and glycosylated hemoglobin levels in high-cholesterol-induced insulin-resistant mice and in type-2 diabetic patients. However, the mechanism by which it exhibits antidiabetic property was unknown. Therefore, the present study was designed to evaluate the effect of troxerutin on insulin signaling molecules in gastrocnemius muscle of high fat and sucrose-induced type-2 diabetic rats. Wistar male albino rats were selected and divided into five groups. Group I: Control. Group II: High fat and sucrose-induced type-2 diabetic rats. Group III: Type-2 diabetic rats treated with troxerutin (150 mg/kg body weight/day orally). Group IV: Type-2 diabetic rats treated with metformin (50 mg/kg body weight/day orally). Group V: Normal rats treated with troxerutin (150 mg/kg body weight/day orally). After 30 days of treatment, fasting blood glucose, oral glucose tolerance, serum lipid profile, and the levels of insulin signaling molecules, glycogen, glucose uptake, and oxidation in gastrocnemius muscle were assessed. Diabetic rats showed impairment in insulin signaling molecules (IR, p-IRS-1(Tyr632), p-Akt(Ser473), ß-arrestin-2, c-Src, p-AS160(Thr642), and GLUT4 proteins), glycogen concentration, glucose uptake, and oxidation. Oral administration of troxerutin showed near normal levels of blood glucose, serum insulin, lipid profile, and insulin signaling molecules as well as GLUT4 proteins in type-2 diabetic rats. It is concluded from the present study that troxerutin may play a significant role in the management of type-2 diabetes mellitus, by improving the insulin signaling molecules and glucose utilization in the skeletal muscle.

The cocoa flavanol (-)-epicatechin protects the cortisol response.

Various health benefits of the cocoa flavanol (-)-epicatechin (EC) have been attributed to its antioxidant and anti-inflammatory potency. In the present study we investigated whether EC is able to prevent deterioration of the anti-inflammatory effect of the glucocorticoid (GC) cortisol in the presence of oxidative stress. It was found that cortisol reduces inflammation in differentiated monocytes. Oxidative stress extinguishes the anti-inflammatory effect of cortisol, leading to cortisol resistance. EC reduces intracellular oxidative stress as well as the development of cortisol resistance. This further deciphers the enigmatic mechanism of EC by which it exerts its anti-inflammatory and antioxidant action. The observed effect of the cocoa flavanol EC will especially be of relevance in pathophysiological conditions with increased oxidative stress and consequential GC resistance and provides a fundament for the rational use of dietary antioxidants.