Effect of chrysin on hepatoprotective and antioxidant status in D-galactosamine-induced hepatitis in rats

Chrysin and luteolin alleviate vascular complications associated with insulin resistance mainly through PPAR-γ activation

Chrysin and luteolin are two flavonoids with Peroxisome proliferators-activated receptor γ (PPAR-γ) stimulating activity. Here, we investigated the protective effect of chrysin and luteolin from vascular complications associated with insulin resistance (IR). IR was induced in rats by drinking fructose for 12 weeks while chrysin and luteolin were given for 6 weeks with or without PPAR-γ antagonist, bisphenol A diglycidyl ether (BADGE). Then, blood pressure (BP) was recorded and serum levels of glucose, insulin, advanced glycation end products (AGEs) and lipids were measured. Concentration response curves for phenylephrine (PE), KCl, and acetylcholine (ACh) were obtained in thoracic aorta rings. Aortic reactive oxygen species (ROS) and nitric oxide (NO) generation were also studied. Chrysin and luteolin significantly alleviated systolic BP elevations caused by IR, while the co-administration of BADGE prevented chrysin alleviation. Although, neither chrysin nor luteolin affected ACh impaired vasodilatation, they both alleviated exaggerated vasoconstrictions to PE and KCl in IR animals. In addition, incubation of the aorta from IR animals with chrysin or luteolin prevented exaggerated vasoconstrictions to PE and KCl. On the other hand, co-administration of BADGE or co-incubation with GW9662, the selective PPAR-γ antagonist, prevented chrysin alleviation. Both chrysin and luteolin inhibited the developed hyperinsulinemia and increases in serum AGEs, lipids while, BADGE reduced the effect of chrysin on hyperinsulinemia and dyslipidemia. Chrysin and luteolin markedly inhibited elevated NO and ROS in IR aortae while BADGE did not change their effect on NO and ROS. In conclusion, chrysin and luteolin alleviate vascular complications associated with IR mainly through PPAR-γ dependent pathways.

Localization and interaction of hydroxyflavones with lipid bilayer model membranes: a study using DSC and multinuclear NMR

The localization and interaction of six naturally occurring flavones (FLV, 5HF, 6HF, 7HF, CHY and BLN) in DPPC bilayers were studied using DSC and multi-nuclear NMR. DSC results indicate that FLV and 6HF interact with alkyl chains. The (1)H NMR shows interaction of flavones with the sn-glycero region. Ring current induced chemical shifts indicate that 6HF and BLN acquire parallel orientation in bilayers. 2D NOESY spectra indicate partitioning of the B-ring into the alkyl chain region. The DSC, NMR and binding studies indicate that 5HF and 7HF are located near head group region, while 6HF, CHY and BLN are located in the vicinity of sn-glycero region, and FLV is inserted deepest in the membrane.

Beneficial effects of Chrysin against Methotrexate-induced hepatotoxicity via attenuation of oxidative stress and apoptosis

Methotrexate (MTX), a folic acid antagonist, an effective chemotherapeutic agent is used in the treatment of a wide range of tumors and autoimmune diseases. Moreover, hepatotoxicity limits its clinical use. Several studies have already confirmed that the oxidative stress plays a major role in the pathogenesis of MTX-induced damage in the various organs especially in liver. The aim of this study was to determine the protective effect of Chrysin against MTX-induced hepatic oxidative stress and apoptosis in rats. In the present study, efficacy of Chrysin was investigated against hepatotoxicity caused by MTX in terms of biochemical investigations of antioxidant enzymes, apoptosis, and histopathological alteration in rat liver. In the MTX-treated group there was a significant increase in alanine transaminase, aspartate aminotransferase, lactate dehydrogenase activity and malondialdehyde content as well as decreased glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase activities and reduced glutathione content were also observed compared to the control group as a marker of oxidative stress. Histopathological alterations and apoptosis through the immunopositive staining of p53, cleaved caspases-3 and Bcl-2-associated X protein in rat liver were observed. Pretreatment of Chrysin at both doses prevents the hepatotoxicity by ameliorating oxidative stress, histopathological alterations, and apoptosis and thus our results suggest that Chrysin has a protective effect against hepatotoxicity induced by MTX and it may, therefore, improve the therapeutic index of MTX if co-administration is done.

Chrysin inhibits metastatic potential of human triple-negative breast cancer cells by modulating matrix metalloproteinase-10, epithelial to mesenchymal transition, and PI3K/Akt signaling pathway

Chrysin, a naturally occurring flavone, has been shown to inhibit cell proliferation and induce cell apoptosis in various cancers. However, the effect and mechanisms of chrysin on cancer metastasis are still enigmatic. In this study, metastatic triple-negative breast cancer (TNBC) cell lines were used to evaluate the antimetastatic activity of chrysin. The results showed that chrysin (5, 10 and 20 μM) significantly suppressed TNBC cell migration and invasion in a dose-dependent manner. Human matrix metalloproteinase (MMP) antibody array demonstrated that MMP-10 was downregulated by chrysin, which was further verified by Western blotting and ELISA. Moreover, it was shown that chrysin induced increased E-cadherin expression and decreased expression of vimentin, snail and slug in TNBC cells, suggesting that chrysin had a reversal effect on epithelial-mesenchymal transition. More importantly, it was demonstrated that inhibiting the Akt signal pathway might play a central role in chrysin-induced antimetastatic activity by regulating MMP-10 and epithelial-mesenchymal transition. In conclusion, our study indicates that chrysin exerts antimetastatic activities in TNBC cells, which suggests that chrysin might be a potential therapeutic candidate for the treatment of advanced or metastatic breast cancer.

Effects of quercetin and chrysin on 2,3,7,8-tetrachlorodibenzo-p-dioxin induced hepatotoxicity in rats

The objective of current study is to investigate the effects of the administration of chrysin (CH) and quercetin (Q) on rat liver in which oxidative and histological damage had been induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were randomly divided into six equal groups. TCDD was orally administered at the dose of 2 μg/kg/week, and Q and CH were orally administered at the doses of 20 mg/kg day and 50 mg/kg/day, respectively, by gavages dissolved in corn oil. The liver samples to be analyzed for the determination of oxidative and histological alternations were taken from rats at 60 days. The results indicated that although 2,3,7,8-TCDD significantly induced (P ≤ 0.01) lipid peroxidation (increase of MDA levels), it positively affected oxidant/antioxidant system (a decline in the levels of GSH, CAT, GSH-Px, and CuZn-SOD) in rats significantly. The histological changes observed in the liver correlated with the biochemical findings. However, these effects of TCDD on oxidative and histological changes were eliminated by Q and CH treatment. In conclusion, TCDD caused an adverse effect on rat's liver. When Q and CH were given together with TCDD, they prevented hepatotoxicty induced by TCDD. Thus, it is thought that Q and CH may be useful as a new category of anti-TCDD toxicity agent.

Quercetin vs chrysin

Effects of flavonoids quercetin and chrysin on lipid peroxidation and histopathological changes in liver of diabetic mice were studied and compared with the antioxidant and reducing ability of quercetin and chrysin and their ability to chelate Fe2+ ions in vitro. Diabetes was induced in Swiss albino mice with a single intravenous injection of alloxan (75 mg kg−1). Two days after alloxan injection, flavonoid preparations (50 mg kg−1 per day) were given intraperitoneally for 7 days in diabetic mice. The lipid peroxidation was evaluated by measuring the malondialdehyde production using the 2-thiobarbituric acid test. Administration of quercetin and chrysin to diabetic mice resulted in a significant decrease in lipid peroxidation level in liver tissue. Treatment of diabetic mice with flavonoids solutions results in decreased number of vacuolated cells and degree of vacuolization of the liver tissue. The protective role of flavonoids against the reactive oxygen species–induced damages in diabetic mice gives a hope that they may exert similar protective action in humans.

Protective Effects of HV-P411 Complex Against D-Galactosamine-Induced Hepatotoxicity in Rats

This study examined the hepatoprotective effect of the HV-P411 complex, an herbal extract mixture from the seeds of Vitis vinifera, Schisandra chinensis and Taraxacum officinale, against D-galactosamine (D-GalN)-induced hepatitis. Hepatotoxicity was induced by D-GalN (700 mg/kg, i.p.), and the HV-P411 complex was administered orally 48, 24, and 2 h before and 6 h after D-GalN injection. Increases in serum aminotransferase activity and lipid peroxidation and a decrease in hepatic glutathione content were attenuated by the HV-P411 complex 24 h after D-GalN treatment. The HV-P411 complex attenuated the increases in serum tumor necrosis factor-α, interleukin (IL)-6 level and cyclooxygenase-2 protein production and their mRNA expressions, while increases in serum IL-10 level and heme oxygenase-1 protein production and their mRNA expressions were augmented by the HV-P411 complex. The increased translocation of nuclear factor-κB and c-Jun phosphorylation were attenuated by treatment with the HV-P411 complex. Our results suggest that the HV-P411 complex prevents D-GalN-induced hepatotoxicity via antioxidative and anti-inflammatory activities.

Ameliorating effects of quercetin and chrysin on 2,3,7,8-tetrachlorodibenzo- p-dioxin-induced nephrotoxicity in rats

The aim of this study is to investigate the beneficial effects of the quercetin (Q) and chrysin (CH) against nephrotoxicity induced by 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD), a persistent environmental contaminant, in rats. Rats were divided randomly into six equal groups. TCDD, Q and CH were administered by gavages dissolved in corn oil at the doses of 2 µg/kg/week, 20 mg/kg/day and 50 mg/kg/day, respectively. The kidney samples were taken from all rats on day 60 for the determination of thiobarbituric acid reactive substances (TBARS), glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) levels by spectrophotometric method. The results indicated that TCDD significantly induced lipid peroxidation and reduced antioxidant activities in rats. In contrast, Q and CH significantly prevented toxic effects of TCDD via increased GSH, CAT, GPx and SOD levels but decreased formation of TBARS. Also, it was determined that exposure to TCDD leads to significant histological damage in kidney tissue, and these effects can be eliminated with Q and CH treatment. In conclusion, the current study showed that exposure to TCDD can exert nephrotoxicity in rats. When Q and CH were given together with TCDD, they prevented nephrotoxic effects of TCDD. Their preventive effect lends more support to the role of oxidative and histological damage in the overall toxicity of TCDD.

Protocatechuic acid prevents reproductive damage caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in male rats

In this study, it was aimed to determinate beneficial effects of protocatechuic acid (PCA) against reproductive toxicity caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an environmental contaminant. For this purpose, 28 rats were equally divided into four groups (control, TCDD 2 μg kg(-1) per week, PCA 100 mg kg(-1) per day and TCDD + PCA group), and compounds were orally administered for 45 days. The results indicated that TCDD induced oxidative stress via an increase in thiobarbituric acid-reactive substances levels and a decrease in reduced glutathione, catalase, glutathione peroxidise and SOD levels in male rats. In contrast, PCA treatment prevented toxic effects of TCDD in terms of oxidative stress. Additionally, sperm motility, sperm concentration and serum testosterone levels significantly decreased, and pathologic testicular damage increased with TCDD exposure. However, these effects of TCDD on sperm characteristics, histopathological changes and hormone levels were reversed by PCA treatment. In conclusion, it was found that TCDD exposure induced reproductive toxicity (oxidative, hormonal, histopathological and spermatological alternations) in male rats and PCA treatment could prevent toxic effects of TCDD. Thus, PCA may be useful for the prevention and treatment of reproductive toxicity caused by TCDD.

Protective effect of propolis against oxidative stress and immunosuppression induced by oxytetracycline in rainbow trout (Oncorhynchus mykiss, W.)

The aim of this study was to investigate the effects of propolis on oxytetracycline (OTC)-induced oxidative stress and immunosuppression in fish. OTC (100 mg per kg⁻¹ body weight) was orally administered to fish for 14 days. A significant elevation in the level of malondialdehyde, as an index of lipid peroxidation, and reductions in antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase) and low molecular weight antioxidant (reduced glutathione) levels were observed in the blood, liver, kidney, spleen, and heart tissues of OTC-treated fish. OTC also had a suppressive effect on specific and non-specific immune system parameters, such as leucocyte counts, oxidative radical production (nitrobluetetrazolium activity), total plasma protein and immunoglobulin levels, and phagocytic activity. Pre-treatment, post-treatment, and simultaneous treatment with propolis (50 mg per kg⁻¹ body weight, orally) attenuated the OTC-induced oxidative stress by significantly decreasing the levels of malondialdehyde in tissues. In addition, propolis significantly increased the level of reduced glutathione and the catalase, glutathione peroxidase, and superoxide dismutase activities. Upon the administration of propolis, the suppressed immune system parameters were significantly increased in fish treated with OTC. The present results suggest that pre-treatment, post-treatment, and simultaneous administration of propolis might alleviate OTC-induced oxidative stress and immunosuppression.

Chrysin modulates ethanol metabolism in Wistar rats: a promising role against organ toxicities

AIMS

Hepato- and nephro-protective efficacy of chrysin was investigated against sequential increase of ethanol intake on the alteration of alcohol metabolizing enzymes-alcohol dehydrogenase (ADH), cytochrome P450 2E1 (CYP 2E1), xanthine oxidase (XO) and oxidant/anti-oxidant status.

METHODS

Thirty female Wistar rats segregated into five groups, each with six animals, were put to different doses. Group I as control followed by Group II, III and IV were treated with ethanol (5,8,10 and 12 g/kg body weight per week respectively) for 4 weeks. While Group III and IV were administered with chrysin at 20 mg (D1) and 40 mg/kg body weight (D2), respectively, prior to ethanol administration. Group V was given only chrysin (D2). Various oxidative stress and ethanol metabolizing enzymes were estimated in hepatic and renal tissues.

RESULTS

Ethanol administration significantly induced CYP 2E1, ADH and XO in liver and kidneys, respectively, along with an enhancement in levels of malondialdehyde and serum alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatinine and lactate dehydrogenase when compared with the control group and this enhancement is significantly normalized with chrysin administration. Oxidative stress markers: reduced glutathione, glutathione peroxidase, catalase and glutathione reductase were significantly (P < 0.001) depleted in the ethanol-treated group, while chrysin administration significantly restored all of these. Only chrysin administration did not show any adverse effect.

CONCLUSION

Results demonstrate that chrysin administration prevents the liver and kidney of Wistar rats against oxidative damage during chronic ethanol consumption by inhibiting the activities of ADH, CYP 2E1, XO and catalase.

Methylated chrysin, a dimethoxy flavone, partially suppresses the development of liver preneoplastic lesions induced by N-nitrosodiethylamine in rats

The modifying effect of chemically modified chrysin on formation of preneoplastic foci induced by N-nitrosodiethylamine (DEN) was investigated in male rats. Male Wistar rats were administered three intraperitoneal injections of DEN (200 mg/kg bodyweight) interspersed by 2 weeks with or without an oral dose of dimethoxy flavone (DMF 100 mg/kg bodyweight), 2 weeks after DEN initiation. The number of GST-Pi positive foci and proliferating cell nuclear antigen (PCNA)-positive cells were significantly suppressed by the administration of DMF. Real-time RT-PCR analysis revealed that DMF treatment increased mRNA expression levels of apoptotic proteins p53 and fas, cell cycle regulatory proteins chek 2, cdkn1a, rad 50, anti-inflammatory protein pparg whereas the mRNA expression levels of bcl-2 and prdx-2 were decreased compared to mRNA levels in DEN-treated group. Therefore, we propose that DMF partially suppresses the formation of preneoplastic lesions in rats following DEN exposure by regulating anti-inflammatory and apoptosis-promoting events and restoring the cellular redox balance altered by DEN.

Synthesis, characterization and vasculoprotective effects of nitric oxide-donating derivatives of chrysin

Vascular complications are major causes of disability and death in patients with diabetes mellitus. It is often characterized by endothelial dysfunction. Studies have shown that either the loss of nitric oxide bioactivity or the decreased biosynthesis of NO is a central mechanism in endothelial dysfunction. As such, the delivery of exogenous NO is an attractive therapeutic option that has been used to slow the progress of diabetic vascular complications. In this paper, a novel group of hybrid nitric oxide-releasing chrysin derivatives was synthesized. The results indicated that all these chrysin derivatives exhibited in vitro inhibitory activities against aldose reductase and advanced glycation end-products formation. And some of them were even found to increase the glucose consumption of HepG2 cells. Furthermore, all compounds released NO upon incubation with phosphate buffer at pH 7.4. These hybrid ester NO donor prodrugs offer a potential drug design concept for the development of therapeutic or preventive agents for vascular complications due to diabetes.