Targeting Skp2 degradation with troxerutin decreases neointima formation.

The proliferative and migratory abilities of vascular smooth muscle cells (VSMCs) play a crucial role in neointima formation following vascular injury. Skp2 facilitates proliferation and migration in cells through cell cycle regulation, presenting an important therapeutic target for atherosclerosis, pulmonary hypertension, and vascular restenosis. This study aimed to identify a natural product capable of inhibiting neointima formation post vascular injury. Here, we demonstrate that troxerutin, a flavonoid, significantly reduced viability and downregulated Skp2 in VSMCs. Moreover, troxerutin exhibited anti-proliferative effects on VSMCs and mitigated neointima formation. These findings collectively elucidate the intrinsic mechanism of troxerutin in treating atherosclerosis, pulmonary hypertension, and vascular restenosis by targeting the E3-linked enzyme Skp2.

The effect of a flavonoid mixture containing diosmin, hesperidin and troxerutin in women with congestion syndrome associated to pelvic pain: a color Doppler ultrasonography study.

BACKGROUND: Pelvic congestion syndrome (PCS) is associated with chronic pelvic pain (CPP). The efficacy of flavonoids for treating PCS symptoms is still a matter of debate, and little has been published. The aim of this study was to assess the efficacy of a mixture of diosmin, troxerutin, and hesperidin in improving symptoms of patients with PCS, observing a direct effect on circulation by specific color Doppler ultrasonography (CDU) evaluations. METHODS: This was a pilot, prospective, independent, cross-over, daily-diary-based trial. Women were evaluated with CDU for 3 times (baseline, 60 days, 120 days). Data about N.=13 women who completed the study were analyzed. RESULTS: During the treatment, we recorded a significant reduction of intermenstrual and menstrual pain intensity (total points) (P<0.05). The satisfaction after treatment was significantly higher than after placebo (P<0.0001). A significant reduction in the diameter of the major ovarian vein (P=0.004 compared to placebo), associated with an increase in peak systolic velocity (P=0.01) and a corresponding significant increase in the Resistivity Index (P<0.0001) were recorded during treatment. CONCLUSIONS: The use of a mixture of diosmin, troxerutin and hesperidin in women with PCS can significantly help to manage typical symptoms of pelvic pain and it is associated with an evident Doppler effect on pelvic microcirculation.

Study of the soothing effects of troxerutin in alleviating skin sensitivity.

BACKGROUND: Transient receptor potential vanilloid 1 (TRPV1) is associated with skin sensitivity and mainly activated by capsaicin and heat. Interestingly, troxerutin can inhibit TRPV1 activation. However, its efficacy in reducing skin sensitivity remains undetermined. AIMS: We evaluated the efficacy of troxerutin in alleviating skin sensitivity using clinical tests and in vitro experiments. METHODS: For the in vitro experiment, HaCaT keratinocytes were pretreated with different concentrations of troxerutin, followed by incubation with 50 µM capsaicin for 1, 24, or 48 h. The gene and protein expressions of four inflammatory cytokines involved in skin irritation were determined. Among 35 Korean women with sensitive skin recruited for the clinical trial, 13 were involved in assessing the immediate soothing effects of 0.1% and 0.0095% troxerutin following capsaicin irritation, whereas 22 participated in evaluating the preventive soothing effect of 10% and 1% troxerutin over 4 weeks against capsaicin- and heat-induced irritation. We evaluated the soothing rate using skin redness, visual analog scale, and high temperature sensitive index as evaluation indices. RESULTS: Troxerutin inhibited the mRNA and protein expressions of cytokines in capsaicin-treated keratinocytes. In the clinical study, 0.1% and 0.0095% troxerutin promptly alleviated capsaicin-induced skin redness, whereas 10% troxerutin notably decreased both the visual analog scale and high temperature sensitive index for capsaicin- and heat-related irritation. However, 1% troxerutin was only effective in reducing the visual analog scale in response to capsaicin irritation. CONCLUSIONS: Troxerutin can inhibit TRPV1 activation in clinical and in vitro tests.

Troxerutin suppress inflammation response and oxidative stress in jellyfish dermatitis by activating Nrf2/HO-1 signaling pathway.

Background: Stomolophus meleagris envenomation causes severe cutaneous symptoms known as jellyfish dermatitis. The potential molecule mechanisms and treatment efficiency of dermatitis remain elusive because of the complicated venom components. The biological activity and molecular regulation mechanism of Troxerutin (TRX) was firstly examined as a potential treatment for jellyfish dermatitis. Methods: We examined the inhibit effects of the TRX on tentacle extract (TE) obtained from S. meleagris in vivo and in vitro using the mice paw swelling models and corresponding assays for Enzyme-Linked Immunosorbent Assay (ELISA) Analysis, cell counting kit-8 assay, flow cytometry, respectively. The mechanism of TRX on HaCaT cells probed the altered activity of relevant signaling pathways by RNA sequencing and verified by RT-qPCR, Western blot to further confirm protective effects of TRX against the inflammation and oxidative damage caused by TE. Results: TE significantly induced the mice paw skin toxicity and accumulation of inflammatory cytokines and reactive oxygen species in vivo and vitro. Moreover, a robust increase in the phosphorylation of mitogen-activated protein kinase (MAPKs) and nuclear factor-kappa B (NF-κB) signaling pathways was observed. While, the acute cutaneous inflammation and oxidative stress induced by TE were significantly ameliorated by TRX treatment. Notablly, TRX suppressed the phosphorylation of MAPK and NF-κB by initiating the nuclear factor erythroid 2-related factor 2 signaling pathway, which result in decreasing inflammatory cytokine release. Conclusion: TRX inhibits the major signaling pathway responsible for inducing inflammatory and oxidative damage of jellyfish dermatitis, offering a novel therapy in clinical applications.

Efficient regioselective enzymatic acylation of troxerutin: difference characterization of in vitro cellular uptake and cytotoxicity.

In this study, we developed a multi-site acylation strategy to improve the lipophilicity and cellular uptake of troxerutin, a natural flavonoid with many health-promoting bioactivities. By clarifying the acylation properties of troxerutin catalyzed by lipases from different sources, a series of troxerutin ester derivatives acylated at different sites was synthesized, including troxerutin dipropyl (TDP), tripropyl (TTP), tetrapropyl (TEP), dibutyl (TDB), monohexyl (TMH), monooctyl (TMO) and monodecyl (TMD) esters. Interestingly, the troxerutin esters acylated at multiple sites with shorter fatty chains (TDP, TTP and TEP) had similar lipophilicity to the mono-acylated esters bearing longer fatty chains (TMH, TMO and TMD, respectively) and meanwhile demonstrated surprisingly lower cytotoxicity than that of the long fatty-chain mono-esters. In particular, the multi-acylated esters with shorter fatty chains showed remarkably higher cellular uptake than the mono-esters with long fatty chains. In vitro gastrointestinal digestion suggested that the multi-acylated esters of troxerutin were more resistant to gastrointestinal degradation than the mono-esters. These results indicated that multi-site acylation with short fatty chains could be an effective alternative to introducing one-site mono-acylation for the modification of troxerutin and other flavonoid compounds.

A mechanistic review of the pharmacological potential of narirutin: a dietary flavonoid.

Flavanones, a type of polyphenol, are found in substantial amounts in citrus fruits. When high- or moderate-dose orange juice consumption occurs, flavanones make up a significant portion of the total polyphenols in plasma. Disaccharide derivative narirutin, mainly dihydroxy flavanone, is found in citrus fruits. The substantial chemotherapeutic potential of narirutin has been amply demonstrated by numerous experimental studies. Consequently, the purpose of this study is to compile the research that has already been done showing narirutin to be a promising anticancer drug, with its mechanism of action being documented in treatment plans for various cancer forms. Narirutin functions in a variety of cancer cells by regulating several pathways that include cell cycle arrest, apoptosis, antiangiogenic, antimetastatic, and DNA repair. Narirutin has been shown to modify many molecular targets linked to the development of cancer, including drug transporters, cell cycle mediators, transcription factors, reactive oxygen species, reactive nitrogen species, and inflammatory cytokines. Taken together, these reviews offer important new information about narirutin's potential as a potent and promising drug candidate for use in medicines, functional foods, dietary supplements, nutraceuticals, and other products targeted at improving the treatment of cancer.

Troxerutin improves cognitive function and forkhead box F2 expression in the hippocampus via modulating the microbial composition and the intestinal barrier function in diabetes mellitus mice.

Recent studies have found that gut microbes may affect blood-brain barrier (BBB) integrity. This study was to investigate the relationship between gut microbes and forkhead box F2 (FOXF2) and the mechanism of troxerutin improving diabetic cognitive dysfunction (DCD). Diabetic mice were used in this study for the prophylactic application of troxerutin (60 mg/kg/d) for 8 weeks. The cognitive function was assessed using the Morris water maze (MWM) and novel object recognition (NOR) tasks, and the changes of intestinal microbial composition were observed through 16S rRNA gene sequencing. The content of short-chain fatty acids (SCFAs) in feces was determined by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and the intestinal barrier function was assessed by enzyme-linked immunosorbent assay (ELISA) and western blotting. Troxerutin up-regulated FOXF2 expression in the hippocampus of mice, improving DCD. Meanwhile, it reversed the intestinal microbial composition (increased the abundance of the phylum Bacteroidota, as well as fecal propionic acid and butyric acid levels) and improved the intestinal barrier (increased the level of claudin-1 and significantly reduced the circulating lipopolysaccharide binding protein (LBP) levels). When intestinal microorganisms were removed with an antibiotic cocktail, the improvement of hippocampal FOXF2 expression and DCD by troxerutin attenuated accordingly, suggesting that troxerutin improved DCD by up-regulating the expression of hippocampal FOXF2 through the regulation of intestinal microbial composition and the intestinal barrier. In summary, troxerutin improved DCD by up-regulating the expression of hippocampal FOXF2 through the regulation of intestinal microbial composition and the intestinal barrier.

Effect of troxerutin consumption during gestation period on reflexive motor behavior in mice offspring.

This study aimed to determine the effects of troxerutin consumption during gestation on reflexive motor behavior in mice offspring. Forty pregnant female mice were allocated into four groups. In the control group, mice received water, while in groups 2-4, female mice p.o. administered troxerutin (50, 100, and 150 mg/kg) at 5, 8, 11, 14, and 17 days of gestation (GD). Following delivery, pups were selected based on their experimental group, and reflexive motor behaviors were determined. Also, serum malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), and total antioxidant status (TAS) were determined. Based on the findings, maternal exposure to troxerutin (100 and 150 mg/kg) increased ambulation scores in offspring's compared with control group (P < 0.05). Also, prenatal exposure to troxerutin increased front- and hind-limb suspension scores in newborns compared with control group (P < 0.05). Maternal exposure to troxerutin increased grip strength and negative geotaxis in newborns in comparison with control mice (P < 0.05). Prenatal exposure to troxerutin (100 and 150 mg/kg) decreased hind-limb foot angle and surface righting in pups compared with control group (P < 0.05). Maternal exposure to troxerutin decreased MDA production and increased SOD, GPx, and TAS levels in offspring (P < 0.05). These results suggested that prenatal consumption of the troxerutin improves reflexive motor behaviors in mice pups.

Troxerutin Abrogates Ischemic/Reperfusion-Induced Brain Injury through Ameliorating Oxidative Stress and Neuronal Inflammation by Inhibiting the Expression of NLRP3 in Sprague Dawley Rats.

Cerebral ischemic reperfusion (I/R) infarction is mostly associated with serious brain injury, cognitive damage, and neurological deficits. The oxidative stress mechanisms in the neurological region lead to higher reactive oxygen species production followed by oxidative stress, inflammation of neurons, and death of brain cells. The current work aims to evaluate the effect of troxerutin (TXN) on cerebral injury stimulated by I/R-induced ischemic stroke and examines the mechanistic effect of TXN on neuroinflammation in the Sprague Dawley model. The experimental rats were randomized in to four groups: (i) sham control, (ii) I/R + vehicle, (iii) I/R + 10 mg/kg bw TXN, and (iv) I/R + 20 mg/kg bw TXN. In the TXN administration and control, groups were injected intraperitoneally 15 min before reperfusion and every day for 7 days, except the sham group. Orally administered TXN (10 and 20 mg/kg/bw) modulated the water content, lowered the infarct volume, and abrogated score defects of neuron and changes in the brain tissue sample. In our study, the TXN-stimulated cerebral injury exhibited leakage of thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH) of the neuronal sample of tissues and showed higher antioxidant enzymes superoxide dismutase, catalase, the oxidized form of glutathione peroxidase, and the reduced form of glutathione levels. This biochemical result was additionally proved by histopathological assessment. Changes were made in antioxidant and inflammatory markers expressions interleukin-6 (IL-6), IL-4, IL-10, vascular endothelial growth factor, and cerebral induced rats. The overall findings showed that TXN protected the brain tissues from neuroinflammatory oxidative stress by reducing cerebral injury in Sprague Dawley rats. Further, the messenger RNA expression of cerebral I/R-induced animal tissues down-regulated NLRP3, caspase-1, tumor necrosis factor-α, ASC, IL-1ß, and Toll-like receptor 3 (TLR3). Therefore, the TXN action on TLR3 induced brain stroke is an excellent therapeutic approach for brain damage.

Anticancer Effect of Troxerutin in Human Non-Small-Cell Lung Cancer Cell A549 and Inhibition of Tumor Formation in BALB/c Nude Mice.

This study is intended to explore the anticancer, antiproliferative, and chemopreventive action of troxerutin (TX) in human non-small-cell lung cancer cell (A549) using BALB/c nude mice. 2 × 106 A549 cells were subcutaneously injected into mice, along with 10 µM and 20 µM/kg body weight of TX orally for 19 days. On the last day, tumor weight and volume were assessed. Stress marker enzymes such as Aryl hydrocarbon hydroxylase (AHH), lactate dehydrogenase (LDH), 5'Nucleotidase (5'ND), and γ-glutamyltranspeptidase (γ-GT) were estimated in the lung tissues. Cytotoxicity of TX was assessed using MTT assay. Expression of carcinoembryonic antigen (CEA) and inflammatory cytokines were also analyzed. Histopathological examination of tissue sections and immunohistochemical examination of proliferating cell nuclear antigen (PCNA) were also performed. mRNA expression of p53, p21, cyclin D1, P13k, Akt, and mTOR were analyzed using RT-PCR. TX administered orally in a dose-dependent manner markedly reverted the level of stress marker enzymes to a significant extent. TX also exhibited significant protection against lung cancer cells, as evidenced by cytotoxicity assay and histopathological studies. It was also found to reduce the expression of PCNA, cyclin D1, P13k, Akt, and mTOR, but increase the expression of p53 and p21. TX has also been shown to reduce cancer cell inflammation, as was evidenced by reduced expression of inflammatory cytokines. Thus TX could be used as an effective chemopreventive and anticancer agent in treating cancer.

The Protective Roles and Molecular Mechanisms of Troxerutin (Vitamin P4) for the Treatment of Chronic Diseases: A Mechanistic Review.

Troxerutin (TRX), a semi-synthetic bioflavonoid derived from rutin, has been reported to exert several pharmacological effects including antioxidant, anti-inflammatory, antihyperlipidemic, and nephroprotective. However, the related molecular details and its mechanisms remain poorly understood. In the present review, we presented evidences from the diversity in vitro and in vivo studies on the therapeutic potential of TRX against neurodegenerative, diabetes, cancer and cardiovascular diseases with the purpose to find molecular pathways related to the treatment efficacy. TRX has a beneficial role in many diseases through multiple mechanisms including, increasing antioxidant enzymes and reducing oxidative damage, decreasing in proapoptotic proteins (APAF-1, BAX, caspases-9 and-3) and increasing the antiapoptotic BCL-2, increasing the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and downregulating the nuclear factor κB (NFκ). TRX also reduces acetylcholinesterase activity and upregulates phosphoinositide 3- kinase/Akt signaling pathway in Alzheimer's disease models. Natural products such as TRX may develop numerous and intracellular pathways at several steps in the treatment of many diseases. Molecular mechanisms of action are revealing novel, possible combinational beneficial approaches to treat multiple pathological conditions.

The bioflavonoid troxerutin prevents gestational hypertension in mice by inhibiting STAT3 signaling.

Gestational hypertension is a high-risk disease for women, and the current treatments have limited efficacies. Here, we aimed to evaluate troxerutin, which is a natural monomer of flavone, in the treatment of gestational hypertension. Pregnant mice with or without pregnancy-induced hypertension (PIH) were treated with troxerutin (20 and 40 mg/kg) or vehicle. Blood pressure and proteinuria were monitored during treatment. The expression of vasodilation converting enzyme (VCE), angiotensin, TNFα, IL-6, IL-1ß and IL-10 was measured by enzyme-linked immunosorbent assay (ELISA). Oxidative stress was assessed by measuring the reactive oxygen species (ROS) levels and antioxidant enzyme concentrations. Western blot analysis was used to assess the expression of p-STAT3, STAT3, SHP-1, and RNF6. Troxerutin reduced blood pressure and the expression of VCE, angiotensin, urinary protein and pro-inflammatory cytokines in a dose-dependent manner while increasing the expression of anti-inflammatory cytokines. The levels of ROS were decreased, and the levels of antioxidant enzymes were increased. Troxerutin treatment significantly suppressed STAT3/RNF6 signaling. Overexpression of RNF6 attenuated the effects of troxerutin in ameliorating inflammation and oxidative stress. Our data support the use of troxerutin for reducing gestational hypertension due to the role of troxerutin in reducing inflammation and oxidative stress.

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.

Troxerutin protects against DHT-induced polycystic ovary syndrome in rats.

The exact pathogenesis of polycystic ovary syndrome (PCOS), the most common neuroendocrine disorder in women of reproductive age, has not been fully elucidated. Recent studies suggested that chronic inflammation and neurotransmitter disorder involved in the progress of PCOS. Troxerutin, a natural flavonoid, was reported to possess neuroprotective effect in several disease models by inhibiting inflammation or enhancing neurotrophic factor. In this study, we investigated the possible protective effect and mechanism of troxerutin in a dihydrotestosterone (DHT)-induced rat model of PCOS. The PCOS rat models were treated with troxerutin at a dose of 150 mg/kg or 300 mg/kg for up to 4 weeks. Results showed that 300 mg/kg troxerutin significantly decreased the body weight gain and improved the pathological changes of ovary induced by DHT. Meanwhile, the elevated gonadotrophin-releasing hormone (GnRH), gonadotrophin and testosterone in the serum of PCOS rats were reduced with the treatment of troxerutin. The expression of kisspeptin and NKB in arcuate nucleus and their receptors kiss1r and NK3r in GnRH positive neurons of median eminence were markedly decreased in troxerutin-treated rats. Of note, the GnRH inhibitory regulator GABA and stimulatory regulator glutamate were also restored to the normal level by troxerutin. The present study indicated that troxerutin may exhibit a protective effect in PCOS rat model via regulating neurotransmitter release.

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.

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 flavonoid has neuroprotective properties and increases neurite outgrowth and migration of neural stem cells from the subventricular zone.

Troxerutin (TRX) is a water-soluble flavonoid which occurs commonly in the edible plants. Recent studies state that TRX improves the functionality of the nervous system and neutralizes Amyloid-ß induced neuronal toxicity. In this study, an in vitro assay based upon Neural stem cell (NSCs) isolated from the subventricular zone of the postnatal balb/c mice was established to explore the impact of TRX on individual neurogenesis processes in general and neuroprotective effect against ß-amyloid 1-42 (Aß42) induced inhibition in differentiation in particular. NSCs were identified exploiting immunostaining of the NSCs markers. Neurosphere clonogenic assay and BrdU/Ki67 immunostaining were employed to unravel the impact of TRX on proliferation. Differentiation experiments were carried out for a time span lasting from 48 h to 7 days utilizing ß-tubulin III and GFAP as neuronal and astrocyte marker respectively. Protective effects of TRX on Aß42 induced depression of NSCs differentiation were determined after 48 h of application. A neurosphere migration assay was carried out for 24 h in the presence and absence of TRX. Interestingly, TRX enhanced neuronal differentiation of NSCs in a dose-dependent manner after 48 h and 7 days of incubation and significantly enhanced neurite growth. A higher concentration of TRX also neutralized the inhibitory effects of Aß42 on neurite outgrowth and length after 48 h of incubation. TRX significantly stimulated cell migration. Overall, TRX not only promoted NSCs differentiation and migration but also neutralized the inhibitory effects of Aß42 on NSCs. TRX, therefore, offers an interesting lead structure from the perspective of drug design especially to promote neurogenesis in neurological disorders i.e. Alzheimer's disease.

Troxerutin attenuates oxygen­glucose deprivation and reoxygenation­induced oxidative stress and inflammation by enhancing the PI3K/AKT/HIF­1α signaling pathway in H9C2 cardiomyocytes.

Myocardial ischemia­reperfusion (MI/R) injury is a complex pathological process that occurs when tissues are reperfused following a prolonged period of ischemia. Troxerutin has been reported to have cardioprotective functions. However, the underlying mechanism by which troxerutin protects against MI/R injury has not been fully elucidated. The aim of the present study was to explore whether troxerutin­mediated protection against oxygen­glucose deprivation/reoxygenation (OGD/R)­induced H9C2 cell injury was associated with the inhibition of oxidative stress and the inflammatory response by regulating the PI3K/AKT/hypoxia­inducible factor­1α (HIF­1α) signaling pathway. The results of the present study suggested that troxerutin pretreatment prevented the OGD/R­induced reduction in cell viability, and the increase in lactate dehydrogenase activity and apoptosis. Troxerutin reversed OGD/R­induced the inhibition of the PI3K/AKT/HIF­1α signaling pathway as demonstrated by the increased expression of PI3K and HIF­1α, and the increased ratio of phosphorylated AKT/AKT. LY294002, a selective PI3K inhibitor, inhibited the PI3K/AKT/HIF­1α signaling pathway and further attenuated the protective effect of troxerutin against OGD/R­induced H9C2 cell damage. Furthermore, small interfering (si)RNA­mediated knockdown of HIF­1α reduced troxerutin­induced protection against OGD/R injury. Troxerutin pretreatment alleviated OGD/R­induced oxidative stress, as demonstrated by the reduced generation of reactive oxygen species and malonaldehyde content, and the increased activities of superoxide dismutase and glutathione peroxidase, which were reduced by HIF­1α­siRNA. Troxerutin­induced decreases in the levels of interleukin (IL)­1ß, IL­6 and tumor necrosis factor­α in OGD/R conditions were also reduced by HIF­1α­siRNA. The results from the present study indicated that troxerutin aggravated OGD/R­induced H9C2 cell injury by inhibiting oxidative stress and the inflammatory response. The primary underlying protective mechanism of troxerutin was mediated by the activation of the PI3K/AKT/HIF­1α signaling pathway.

Troxerutin attenuates cognitive decline in the hippocampus of male diabetic rats by inhibiting NADPH oxidase and activating the Nrf2/ARE signaling pathway.

Diabetes­associated cognitive decline is a recently identified a potential complication of diabetes. The present study was designed to examine the effects of troxerutin, a potent antioxidant, on cognitive function in rats with streptozotocin­induced diabetes and to further explore the potential underlying mechanisms. Cognitive functions were investigated by the Morris water maze test. The malondialdehyde (MDA) level and superoxide dismutase (SOD) activity in the hippocampus were assessed as the parameters of oxidative stress. Subunits of the NADPH oxidase (NOX) expression and nuclear factor erythroid 2­related factor 2/antioxidant responsive element (Nrf2/ARE) signaling pathway were detected to explore the potential underlying mechanisms. The water maze test revealed that troxerutin significantly improved cognitive impairment in diabetic rats. Troxerutin treatment attenuated oxidative stress in the hippocampus of diabetic rats, as evidenced by the decreased MDA level and the increased SOD activity. Moreover, troxerutin activated the Nrf2/ARE signaling pathway via Nrf2 nuclear translocation in the cells in the hippocampus of diabetic rats. Troxerutin elevated the expression levels of the antioxidant enzymes, heme oxygenase­1 (HO­1) and NAD(P)H:quinone oxidoreductase (NQO1), and decreased the expression levels of the NOX subunits, gp91phox, p47phox and p22phox. On the whole, these findings demonstrate that troxerutin exerts neuroprotective effects against diabetes­associated cognitive decline by suppressing oxidative stress in the hippocampus of rats with streptozotocin­induced diabetes. Troxerutin may thus prove to be a potential therapeutic medicine for the treatment of diabetes­associated cognitive decline.