Beneficial effect of hesperidin on lipopolysaccharide-induced hepatotoxicity

Oxidative stress and cancer; the role of hesperidin, a citrus natural bioflavonoid, as a cancer chemoprotective agent

Cancer is the third cause of death worldwide, with complex etiology, and is defined as an uncontrolled growth of cells. A high proportion of cancer incidence and deaths are due to different environmental and genetic factors such as high body mass index, low fruit and vegetable intake, lack of physical activity, tobacco use, alcohol consumption, exposure to radiation, chronic infections, and heredity also. In addition, oxidative stress plays a crucial role in the pathophysiology of different types of cancer. Hence, screening and testing of more effective compounds with minimum side effects for the prevention and treatment of cancers started a few decades ago. Regarding this, much attention has been paid to natural antioxidants as a novel prevention and treatment strategy for cancer. Flavonoids are one of the most important ingredients in vegetables and fruits, especially in the genus Citrus. Hesperidin is a flavonone glycoside, belonging to the flavonoid family, which is widely found in Citrus species and acts as a potent antioxidant and anticancer agent. In the present review, we attempt to provide an overview and summarize the scientific literature about the cancer chemoprotective effects of hesperidin with an emphasis on its relation to the protection roles against oxidative stress.

Protective effects of hesperidin on oxidative stress, dyslipidaemia and histological changes in iron-induced hepatic and renal toxicity in rats

The present study was to evaluate the protective role of hesperidin (HDN) against iron-induced hepatic and renal toxicity in rats. Administration of iron (30 mg/kg body weight) intraperitoneally for 10 days, the levels of serum hepatic markers, renal functional markers, lipid profile, lipid peroxidation markers and iron concentration in blood were significantly (p < 0.05) increased. The toxic effect of iron was also indicated by significant (p < 0.05) decrease in the levels of plasma, liver and kidney of enzymatic and non-enzymatic antioxidants. Administration of hesperidin at different doses (20, 40 and 80 mg/kg body weight) significantly (p < 0.05) reversed the levels of serum hepatic markers, renal functional markers, lipid profile, lipid peroxidation markers, restored the levels of hepatic, renal enzymatic antioxidants and non-enzymatic antioxidants with decrease in iron concentration in blood. Hesperidin at a dose of 80 mg/kg body weight exhibits significant protection on hepatic and renal when compared with other two doses (20 and 40 mg/kg body weight). All these changes were corroborating by histological observations of liver and kidney. This study demonstrated the protective role of hesperidin in reducing toxic effects of iron in experimental rats.

Amelioration of lipopolysaccharide-induced liver injury by aqueous rooibos (Aspalathus linearis) extract via inhibition of pro-inflammatory cytokines and oxidative stress

BACKGROUND

Acute liver injury occur after intraperitoneal administration of lipopolysaccharide (LPS). Oxidative stress and release of pro-inflammatory cytokines are both implicated in the pathogenesis of LPS-induced acute liver injury. This study investigated the ameliorative effect of fermented rooibos (Aspalathus linearis) extract on LPS-induced acute liver injury.

METHOD

Major phenolic compounds in the fermented rooibos extract by HPLC-DAD, as well as the in vitro antioxidant capacity were quantified before the start of the experiment. Male Wistar rats were randomized into 4 groups (n = 10 per group) and given either water or fermented rooibos extract for 4 weeks before LPS injection. Hepatic function markers, including aminotransferases and lactate dehydrogenase, lipid peroxidation markers, antioxidant enzymes, glutathione redox status, as well as cytokine levels were monitored in the rats.

RESULTS

Injection of LPS significantly increased serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH). Oxidative stress, evidenced by increased thiobarbituric acid reactive substances (TBARS) measured as malondialdehyde (MDA) in plasma and liver, and decreased glutathione redox status (GSH: GSSG ratio) in whole blood and liver was induced in LPS-challenged rats. Furthermore, hepatic levels of pro-inflammatory response markers TNF-α, IL-1β and IL-6 were increased significantly. Pre-feeding the fermented rooibos extract for 4 weeks decreased LPS-induced elevated levels of serum AST and LDH (significantly, p < 0.05) as well as ALT marginally. Consuming rooibos caused an attenuation of the observed increase in plasma and hepatic MDA, decrease in whole blood and liver GSH:GSSG ratio, as well as the changes noted in various antioxidant enzymes. The elevation in TNF-α and IL-6 was significantly suppressed, indicating an inhibition of the induced inflammatory response by rooibos.

CONCLUSION

Overall, our data showed that aqueous rooibos extract attenuated LPS-induced liver injury possibly by modulating oxidative stress and suppressing pro-inflammatory cytokines formation.

Evaluation of antioxidant activities of ampelopsin and its protective effect in lipopolysaccharide-induced oxidative stress piglets

The aim of this study was to investigate the antioxidant potential of ampelopsin (APS) by using various methods in vitro, as well as to determine effects of APS on LPS-induced oxidative stress in piglets. The results showed that APS exhibited excellent free radical scavenging by DPPH, ABTS, O₂•⁻, H₂O₂ and ferric reducing antioxidant power. Ampelopsin also protected pig erythrocytes against AAPH-induced apoptosis and hemolysis, decreased total superoxide dismutase activity, and increased lipid peroxidation. Furthermore the results demonstrated that APS enhanced the total antioxidant capacity and decreased the malondialdehyde and protein carbonyl contents in LPS-treated piglets. The results of the present investigation suggest that APS possesses a strong antioxidant activity and alleviates LPS-induced oxidative stress, possibly due to its ability to prevent reactive oxygen species.

Antioxidant effects of cranberry powder in lipopolysaccharide treated hypercholesterolemic rats

This study was conducted to investigate the effects of cranberry power on antioxidant defense system in rats fed an atherogenic diet and injected with lipopolysaccharide (LPS). Sprague-Dawley rats were divided into the following 5 groups: normal diet+saline (NS), atherogenic diet+saline (AS), atherogenic diet+LPS (AL), atherogenic diet with 5% cranberry powder+LPS (AL-C5), and atherogenic diet with 10% cranberry powder+LPS (AL-C10). Total antioxidant status measured by ferric reducing ability of plasma (FRAP) was significantly reduced by LPS injection (24%) and was restored by the cranberry powder treatment (P<0.05). In addition, the mean level of plasma total phenolics was significantly decreased by LPS injection (P<0.05) and tended to be increased when cranberry powder was incorporated in to the diet. Activity of serum superoxide dismutase (SOD) tended to be lowered by LPS injection and declined further in cranberry powder fortified groups. Overall results indicate that dietary cranberry powder may provide appropriate antioxidants to counter the diminished antioxidant status induced by exposing hypercholesterolemic rats to LPS.

Hesperidin, a flavanoglycone attenuates experimental diabetic neuropathy via modulation of cellular and biochemical marker to improve nerve functions

AIM

Diabetic neuropathy (DN) is one of the most common long-term complications of diabetes mellitus and clinically can be characterized by an elevated nociceptive response with electrophysiological conduction abnormalities. The present investigation was designed to evaluate the neuroprotective effect of hesperidin against STZ induced diabetic neuropathic pain in laboratory rats.

MATERIALS AND METHODS

DN was induced in Sprague-Dawley rats (150-200 g) by intraperitoneal administration of streptozotocin (STZ) (55 mg/kg, p.o.). Rats were divided into various groups, namely, STZ control (vehicle), hesperidin (25, 50, and 100 mg/kg, p.o.), insulin (10 IU/kg, s.c.), and combination of hesperidin (100 mg/kg, p.o.) with insulin (10 IU/kg, s.c.) for 4 weeks. Various behavioral (allodynia and hyperalgesia), biochemical parameters [oxido-nitosative stress, Na-K-ATPase, aldose reductase (AR)], and molecular changes (TNF-α and IL-1β) along with hemodynamic changes were determined.

RESULTS

Rats treated with hesperidin (50 and 100 mg/kg, p.o., 4 weeks) significantly reduced (p < 0.05) hyperglycemia and its metabolic abnormalities induced by intraperitoneal administration of STZ. The decreased nociceptive threshold, motor nerve conduction velocity (MNCV) and sensory nerve conduction velocity (SNCV), serum insulin as well as Na-K-ATPase activity were significantly increase (p < 0.05) by hesperidin (50 and 100 mg/kg, p.o.) treatment. It significantly attenuated (p < 0.05) elevated glycated hemoglobin, AR activity, oxido-nitrosative stress, neural calcium, and pro-inflammatory cytokines (TNF-α and IL-1β) levels. Histological aberration induced after STZ administration was restored by administration of hesperidin (50 and 100 mg/kg, p.o.)

CONCLUSION

In combination with insulin, hesperidin not only attenuated the diabetic condition but also reversed neuropathic pain via control over hyperglycemia as well as hyperlipidemia to down-regulate generation of free radical, release of pro-inflammatory cytokines as well as elevation in membrane bound enzyme.

Ethanolic extract of Boswellia ovalifoliolata bark and leaf attenuates doxorubicin-induced cardiotoxicity in mice

The aim of the study was to investigate the potential protective effect of ethanolic extract of Boswellia ovalifoliolata (BO) bark and leaf against doxorubicin (DOX)-induced cardiotoxicity in mice. Ethanolic extracts of BO bark (400 mg/kg) and leaves (250 mg/kg) were given orally to mice for 9 consecutive days and DOX (15 mg/kg; i.p.) was administered on the seventh day. Extract protected against DOX-induced ECG changes. It significantly inhibited DOX-provoked glutathione depletion and accumulation of malondialdehyde. The decrease in antioxidant enzyme activities of catalase, superoxide dismutase, glutathione peroxidase in cardiac tissue were significantly (p<0.05) mitigated after treatment with BO bark and leaf extracts. Pretreatment with BO significantly (p<0.05) restored the levels of DOX-induced rise of SGPT, SGOT, serum lactate dehydrogenase and creatine kinase-MB levels. These findings suggest that ethanolic extract of BO has protective effects against DOX-induced cardiotoxicity.

Modulating effects of hesperidin on key carbohydrate-metabolizing enzymes, lipid profile, and membrane-bound adenosine triphosphatases against 7,12-dimethylbenz(a)anthracene-induced breast carcinogenesis

The aim of this study was to document the effect of hesperidin on the key enzyme activities of carbohydrate metabolism, lipid profile, and membrane-bound adenosine triphosphatases (ATPases) during 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast carcinogenesis. Hesperidin has been reported to have multiple biological properties. Breast cancer was induced by single dose of DMBA (20 mg/kg body weight (bw)). The results revealed that there was a significant increase in the activities of hexokinase, phosphoglucoisomerase, and aldolase and a concomitant decrease in the activities of glucose-6-phosphatase and fructose-1,6-diphosphatase in cancer-induced animals. The activities of ATPases were found to be decreased both in erythrocyte membrane and in the liver of mammary cancer-bearing animals. The lipid profiles such as total cholesterol, free cholesterol, phospholipids, triglycerides, and free fatty acids significantly increased and in contrast the ester cholesterol in plasma was found to be decreased, whereas it was found to be elevated in the liver of cancer-bearing groups. The altered levels of the above-mentioned biochemical parameters in cancer-bearing animals were significantly ameliorated by the administration of hesperidin at the dosage of 30 mg/kg bw for 45 days. The histopathological analysis of breast and liver tissues were well supported the modulatory property of hesperidin, and this might be associated with normalizing the gluconeogenesis process, stabilization of cell membranes, and modulation of lipid biosynthesis.

Effect of hesperidin pretreatment on the expression of apoptosis-related genes in the liver of mice with acetaminophen-induced acute liver injury

AIM: To investigate the protective effect of hesperidin (HDN) pretreatment on the expression of apoptosis-related genes in the liver of mice with acetaminophen (APAP)-induced acute liver injury.

METHODS: Sixty male Balb/c mice were randomly divided into six groups, including normal group, model group, bifendate group, low-, medium-, and high-dose HDN groups. The HDN groups were intragastrically given different doses of hesperidin for 10 d. The bifendate group was given bifendate. Acute liver injury was induced by injecting APAP in all mice except those in the normal group. After 16 h, all mice were sacrificed. Liver index was calculated. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The activity of superoxide dismutase (SOD) and the contents of glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) in liver homogenates were determined. Pathological changes in hepatic tissue were observed under an optical microscope. Apoptosis of hepatic cells was detected by TUNEL assay. The expression of Bcl-2 and Bax mRNAs in hepatic tissue was measured by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS: Compared to the normal group, liver index, serum levels of ALT and AST, and the contents of MDA were significantly increased, and the activity of SOD and contents of GSH-PX in liver homogenates were significantly decreased in the model group (5.41% ± 0.68% vs 4.38% ± 0.17%, 1456.49 U/L ± 413.45 U/L vs 45.36 U/L ± 11.98 U/L, 1929.34 U/L ± 810.19 U/L vs 78.49 U/L ± 10.22 U/L, 32.04 nmol/mgprot ± 9.32 nmol/mgprot vs 11.83 nmol/mgprot ± 1.72 nmol/mgprot, 119.29 U/mgprot ± 33.02 U/mgprot vs 327.22 U/mgprot ± 26.66 U/mgprot, 75.89 μmol/L ± 20.21 μmol/Lvs 122.73 μmol/L ± 6.70 μmol/L, all P < 0.01). However, liver index, serum levels of ALT and AST, and the contents of MDA were significantly lower, and the activity of SOD and contents of GSH-PX were significantly higher in the bifendate group, high- and medium-dose HDN groups than in the model group (4.65% ± 0.61%, 4.59% ± 0.57%, 4.73% ± 0.63%vs 4.38% ± 0.17%; 66.36 U/L ± 13.43 U/L, 225.29 U/L ± 53.02 U/L, 773.06 U/L ± 251.27 U/L vs 1456.49 U/L ± 413.45 U/L; 105.75 U/L ± 17.02 U/L, 540.92 U/L ± 170.57 U/L, 906.78 U/L ± 226.38 U/L vs 1929.34 U/L ± 810.1 U/L; 15.74 nmol/mgprot ± 2.98 nmol/mgprot, 16.04 nmol/mgprot ± 4.92 nmol/mgprot, 20.85 nmol/mgprot ± 6.04 nmol/mgprot vs 32.04 nmol/mgprot ± 9.32 nmol/mgprot; 222.52 U/mgprot ± 56.11 U/mgprot, 245.95 U/mgprot ± 41.90 U/mgprot, 198.12 U/mgprot ± 68.09 U/mgprot vs 119.29 U/mgprot ± 33.02 U/mgprot; 108.70 μmol/L ± 25.96 μmol/L, 107.39 μmol/L ± 32.60 μmol/L, 98.90 μmol/L ± 10.71 μmol/L vs 75.89 μmol/L ± 20.21 μmol/L, all P < 0.01 or 0.05). The spleen index showed no significant differences among each group (all P > 0.05). Massive patchy necrosis surrounding the central vein, cellular swelling, massive inflammatory cell infiltration, and significant liver cell apoptosis were observed in liver tissues of mice in the model group; however, these pathological changes and cell apoptosis were significantly alleviated in the bifendate group and HDN groups. Such improvement was most obvious in the bifendate group and high-dose HDN group. APAP could significantly up-regulate Bax mRNA expression, down-regulate Bcl-2 mRNA expression, and decrease the Bcl-2/Bax ratio (0.68 ± 0.03 vs 0.28 ± 0.02, 0.21 ± 0.04 vs 0.58 ± 0.01; both P < 0.01). However, Bcl-2 mRNA expression was significantly up-regulated, Bax mRNA expression was significantly down-regulated and the Bcl-2/Bax ratio was significantly increased in the bifendate group, high- and medium-dose HDN groups (0.22 ± 0.04, 0.56 ± 0.01, 0.75 ± 0.01 vs 0.21 ± 0.04; 0.67 ± 0.06, 0.26 ± 0.005, 0.28 ± 0.02 vs 0.68 ± 0.03, all P < 0.05).

CONCLUSION: HDN pretreatment protects mice from acetaminophen-induced liver injury possibly via mechanisms associated with inhibiting lipid peroxidation and regulating the expressions of apoptosis-related genes.

Protective effects of propolis on female rats' histopathological, biochemical and genotoxic changes during LPS induced endotoxemia

In recent years, propolis has been the object of extensive research for its antibacterial, antioxidant, anti-inflammatory, and antitumoral activities. This study aims to determine the hepatoprotective efficiency of propolis on experimental endotoxemia in rats. In the current study, fifty adult Sprague Dawley rats (weighing 200-300 g) were randomly divided into five groups of ten rats each. Normal saline solution was administered to the rats in the control group, while in the second group LPS (30 mg/kg), in the third group propolis (250 mg/kg), in the fourth group first propolis and then LPS (30 mg/kg), and in the fifth group, first LPS (30 mg/kg) and then propolis were given. Six hours after the application, biochemical (MDA levels) and histopathological changes as well as global DNA methylation analysis in the liver tissue samples were determined, while in the blood tissue samples Genomic Template Stability (GTS, %) was evaluated using RAPD-PCR profiles. The results demonstrated that the administration of propolis could have a protective effect against changes of both genomic stability values and methylation profiles, and it minimized the increase in MDA and tissue damage caused by LPS. In conclusion, the application of propolis prior to LPS-induced endotoxemia has shown to reduce hepatic damage.

Phytochemicals in ocular health: Therapeutic potential and delivery challenges

Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are the leading causes of blindness in adults. The impact of these conditions on the quality of life is increasing in significance with a rise in life expectancy. The role of hyperglycemia, oxidative stress and inflammatory responses in the development and/or progression of DR and AMD, and several other sight threatening ocular diseases, is well established. In proliferative retinopathy, signals sent by the retina for nourishment, triggers the growth of fragile and abnormal blood vessels. Changes in ocular pressure may lead to rupture of these blood vessels causing severe vision problems. Recent in vitro and preclinical studies demonstrate that certain phytochemicals possessing potent antioxidant and anti-inflammatory activity and ocular blood flow enhancing properties may be very useful in the treatment of, or as a prophylactic measure for, DR and AMD. Apart from these properties they have also been investigated for their anti-bacterial, hormonal, enzyme stimulation, and anti-angiogenic activities. The attractive aspect of these potential therapeutic candidates is that they can act on multiple pathways identified in the etiology of DR, AMD, cataract and other ocular diseases. However, results from clinical trials have been somewhat ambiguous, raising questions about the concentrations of these bioflavonoids achieved in the neural retina following oral administration. Unfortunately, as of date, an efficient noninvasive means to deliver therapeutic agents/candidates to the back-of-the eye is still not available. This review examines some of these promising natural agents and discusses the challenges encountered in delivering them to the posterior segment ocular tissues through the oral route.

Hesperidin-mediated expression of Nrf2 and upregulation of antioxidant status in senescent rat heart

OBJECTIVES

Oxidative stress is recognized as a key element responsible for the development of age-related pathologies. A declining endogenous defence system during senescence dictates the need for supplementation with exogenous antioxidants through diet. Hesperidin is a naturally occurring flavonone present in citrus fruits and has been shown to have many biological properties, including antioxidant activity. We investigated whether hesperidin supplementation could be valuable in protecting cardiac tissue of aged rats against age-related increase in oxidative stress, as well as the mechanism by which it can boost the antioxidant status of the cell.

METHODS

The activity of antioxidant enzymes, mRNA expression of Nrf2, protein levels of superoxide dismutase and catalase were measured using standard protocols.

KEY FINDINGS

Hesperidin treatment effectively protected aged rat heart by increasing the activity of enzymic antioxidants. Hesperidin upregulated the protein levels of nuclear factor erythroid 2-related factor 2, which is responsible for maintaining the antioxidant status of the cell.

CONCLUSIONS

Hesperidin could be useful in protecting cardiomyocytes against age-related increase in oxidative stress mediated by Nrf2 upregulation.

Topical hesperidin improves epidermal permeability barrier function and epidermal differentiation in normal murine skin

Orange peel extract appears to exhibit beneficial effects on skin whitening, inflammation, UVB protection, as well as keratinocyte proliferation. In the present study, we determine whether topical hesperidin influences epidermal permeability barrier function and its underlying mechanisms. Hairless mice were treated topically with 2% hesperidin or 70% ethanol alone twice daily for 6 days. At the end of treatment, basal transepidermal water loss (TEWL) was measured 2 and 4 h post barrier disruption. Epidermal proliferation and differentiation were evaluated by immunohistochemical staining and Western blot analysis. Additionally, lamellar body density and secretion were assessed by electron microscopy. Although there were no significant differences in basal barrier function, in comparison with control animals, topical hesperidin significantly accelerated barrier recovery at both 2 and 4 h after acute barrier abrogation. Enhanced barrier function in hesperidin-treated skin correlated with stimulation of both epidermal proliferation and differentiation, as well as enhanced lamellar body secretion. These results indicate that topical hesperidin enhances epidermal permeability barrier homeostasis at least in part due to stimulation of epidermal proliferation, differentiation, as well as lamellar body secretion.

Effects of orange juice and hesperetin on serum paraoxonase activity and lipid profile in hyperuricemic rats

INTRODUCTION

Hypouricemic, antioxidant and xanthine oxidase inhibitory effects of orange juice and hesperetin have been already indicated. The objective of this study was to investigate the effects of orange juice and hesperetin on paraoxonase and arylesterase activity and lipid profile of hyperuricemic rats.

METHODS

Forty eight male Wistar rats were divided into 8 equal groups of healthy control, healthy+orange juice, healthy+hesperetin, healthy+allopurinol, hyperuricemic control, hyperuricemic+orange juice, hyperurice-mic+hesperetin and hyperuricemic+allopurinol. Hyperuricemia was induced using potassi-um oxonate (250 mg/kg ip). The treatments were carried out by daily gavage of 5 ml/kg orange juice, 5 mg/kg hesperetin and 5 mg/kg allopurinol for 2 weeks. Paraoxonase activi-ty in serum was measured spectrophotometrically using paraoxon and phenylacetate as substrates. Serum lipids levels were determined using enzymatic colorimetric methods.

RESULTS

Hyperuricemia-induced reduction of paraoxonase and arylesterase activity was restored after treatment with orange juice and hesperetin (p<0.05). The effect of both treatments on lipid profile was marginal and only orange juice could significantly increase the levels of HDL-C.

CONCLUSION

Supplementation of orange juice and hesperetin could restore paraoxonase and arylesterase activity in hyperuricemic rats. Orange juice could also partially improve the lipid profile. These effects could have major implications with respect to the prevention of cardiovascular disease in hyperuricemic patients. However, more studies are needed in future investigations.

Antioxidant and anti-inflammatory activities of aqueous extracts of Schizonepeta tenuifolia Briq

This study investigated the antioxidative and anti-inflammatory activities of aqueous extracts of Schizonepeta tenuifolia Briq. (STE). The results showed that STE displayed radical scavenging and reducing activity, as well as liposome protection activity. In addition, the implementation of an HPLC with a photodiode array detector helped to identify polyphenolic components including hesperidin, luteolin, and diosmetin. STE administration in the range of 125-500 mg/kg showed concentration dependent inhibition on carrageenan induced inflammatory response in mice. The anti-inflammatory effects of STE could be related to tissue NO and tumor necrosis factor a (TNF-α) suppression, and associated with the reduction of lipid peroxidation and an increase in antioxidant enzyme activities including catalase, superoxide dismutase, and glutathione peroxidase in vivo. Overall, the results showed that STE might serve as a natural inhibitor of oxidation and inflammation.

Antiasthmatic effects of hesperidin, a potential Th2 cytokine antagonist, in a mouse model of allergic asthma

Background and Objective. The features of asthma are airway inflammation, reversible airflow obstruction, and an increased sensitivity to bronchoconstricting agents, termed airway hyperresponsiveness (AHR), excess production of Th2 cytokines, and eosinophil accumulation in the lungs. To investigate the antiasthmatic potential of hesperidin as well as the underlying mechanism involved, we studied the inhibitory effect and anti-inflammatory effect of hesperidin (HPN) on the production of Th2 cytokines, eotaxin, IL-17, -OVA-specific IgE in vivo asthma model mice. Methods. In this paper, BALB/c mice were systemically sensitized to ovalbumin (OVA) followed intratracheally, intraperitoneally, and by aerosol allergen challenges. We investigated the effect of HPN on airway hyperresponsiveness, pulmonary eosinophilic infiltration, various immune cell phenotypes, Th2 cytokine production and OVA-specific IgE production in a mouse model of asthma. Results. In BALB/c mice, we found that HPN-treated groups had suppressed eosinophil infiltration, allergic airway inflammation, and AHR, and these occurred by suppressing the production of IL-5, IL-17, and OVA-specific IgE. Conclusions. Our data suggest that the therapeutic mechanism by which HPN effectively treats asthma is based on reductions of Th2 cytokines (IL-5), eotaxin, OVA-specific IgE production, and eosinophil infiltration via inhibition of GATA-3 transcription factor.

Hesperidin, a flavanone glycoside, on lipid peroxidation and antioxidant status in experimental myocardial ischemic rats

Myocardial infarction continues to be a leading cause of mortality world-wide. Novel therapies are needed to treat the myocardial ischemia. This study was undertaken to evaluate the cardioprotective role of hesperidin on isoproterenol-induced myocardial ischemia in rats. Myocardial ischemia was induced by subcutaneous injection of isoproterenol hydrochloride (85 mg/kg body weight), for two consecutive days. Isoproterenol-administered rats showed elevated levels of cardiac markers (aspartate transaminase, alanine transaminase, lactate dehydrogenase, creatine kinase, creatine kinase-MB, cardiac troponins T and I) when compared with control and hesperidin treatment groups (100, 200 and 400 mg/kg body weight). The serum levels of cardiac markers were significantly reduced at the doses of 200 mg and 400 mg. All further experiments were carried out at the 200 mg dose. Lipid peroxidation markers (thiobarbituric acid reactive substances, lipid hydroperoxides and conjugated dienes) were elevated significantly in the plasma and heart whereas non-enzymic antioxidants (vitamin C, vitamin E and reduced glutathione) were decreased significantly. Activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and glutathione reductase declined significantly in the heart of ischemic rats. However, after hesperidin treatment, all the above parameters reverted to normal levels. This study demonstrated that the cardioprotective effect of hesperidin on ischemic rats could be due to its anti-lipid peroxidative and antioxidant properties.

Lipopolysaccharide-induced hepatic oxidative injury is not potentiated by knockout of GPX1 and SOD1 in mice

Knockout of copper, zinc-superoxide dismutase (SOD1) and (or) cellular glutathione peroxidase (GPX1) has been reported to have dual impacts on coping with free radical-induced oxidative injury. Because bacterial endotoxin lipopolysaccharide (LPS) triggers inflammatory responses involving the release of cytokines, nitric oxide and superoxide in targeted organs such as liver, in this study we used SOD1 knockout (SOD1-/-), GPX1 knockout (GPX1-/-), GPX1 and SOD1 double-knockout (DKO) and their wild-type (WT) mice to investigate the role of these two antioxidant enzymes in LPS-induced oxidative injury in liver. Mice of the four genotypes (2 month old) were killed at 0, 3, 6 or 12 h after an i.p. injection of saline or 5 mg LPS/kg body weight. The LPS injection caused similar increase in plasma alanine aminotransferase among the four genotypes. Hepatic total glutathione (GSH) was decreased (P<0.05) compared with the initial values by the LPS injection at all time points in the WT mice, but only at 6 and 12 h in the other three genotypes. The GSH level in the DKO mice was higher (P<0.05) than in the WT at 6 h. Although the LPS injection resulted in substantial increases in plasma NO in a time-dependent manner in all genotypes, the NO level in the DKO mice was lower (P<0.05) at 3, 6 and 12 h than in the WT. The level in the GPX1-/- and SOD1-/- mice was also lower (P<0.05) than in the WT at 3 h. The LPS-mediated hepatic protein nitration was detected in the WT and GPX1-/- mice at 3, 6 or 12 h, but not in the SOD1-/-. In conclusion, knockout of SOD1 and (or) GPX1 did not potentiate the LPS-induced liver injury, but delayed the induced hepatic GSH depletion and plasma NO production.

Evaluation of antioxidative and anti-inflammatory potential of hesperidin and naringin on the rat air pouch model of inflammation

BACKGROUND

Anti-inflammatory and antioxidative potential of hesperidin and naringin was carried out considering the rat air pouch model of inflammation.

METHODS

Reference dose of hesperidin (H) or naringin (N) or indomethacin (I) was administered to the rat air pouches. The pouches were induced by injecting sterile air into the intra-scapular region of the rats followed by carrageenan (AP + C) administration. Rats injected only with air (AP) served as controls.

RESULTS

The AP + C group, showed an increase in the exudate lipid peroxidation (LPO), reduced glutathione (GSH), TNF-α, activity of catalase (CAT), total leukocytes and neutrophils along with tissue edema and infiltration of inflammatory cells. Increases in tissue nitrite, LPO, GSH, SOD (superoxide dismutase) and CAT were recorded. Increased CAT and SGPT with concomitant decrease in ALP were observed in serum. When treated with indomethacin (AP + C + I), all the alterations in the exudate, tissue and serum shifted towards normalcy, except LPO in exudate and nitrite in tissue, while, hesperidin (AP + C + H) or naringin (AP + C + N) treatment normalized all the alterations.

CONCLUSION

It seems that both naringin and hesperidin are anti-inflammatory and antioxidative in nature, but hesperidin proved to be better than indomethacin and naringin because of more pronounced pharmacological actions without tissue toxicity.

Hepatoprotective effects of flavonoids from shekwasha (Citrus depressa) against D-galactosamine-induced liver injury in rats

We attempted to isolate the constituent(s) responsible for the suppressive effect of the juice of shekwasha, a citrus produced in Okinawa Prefecture, on D-galactosamine (GalN)-induced liver injury in rats. Liver injury-suppressive activity, as assessed by plasma alanine aminotransferase and aspartate aminotransferase activities, was found only in the fraction that was extracted with n-hexane when three fractions were added to the diet and fed to rats. Of five compounds isolated from the n-hexane-soluble fraction by silica gel column chromatography, three compounds had liver injury-suppressive effects when five compounds were singly force-fed to rats at a level of 300 mg/kg body wt 4 h before the injection with GalN. The structures of the three active compounds were determined as 3',4',5,6,7,8-hexamethoxyflavanone (citromitin), 4',5,6,7,8-pentamethoxyflavone (tangeretin) and 3',4',5,6,7,8-hexamethoxyflavone (nobiletin), which are known flavonoids mainly existing in citrus. Nobiletin, the most important compound in the n-hexane-soluble fraction, also had suppressive effects on liver injuries induced by carbon tetrachloride, acetaminophen and GalN/lipopolysaccharide (LPS) in addition to liver injury induced GalN. Nobiletin suppressed GalN/LPS-induced increases in plasma tumor necrosis factor (TNF)-alpha and nitric oxide (NO) concentrations and hepatic mRNA levels for inducible NO synthase and DNA fragmentation. These results suggest that nobiletin suppressed GalN/LPS-induced liver injury at least by suppressing the production of both TNF-alpha and NO. The results obtained here indicate that the hepatoprotective effect of shekwasha juice is mainly ascribed to several polymethoxy flavonoids included in the juice.

Lipid lowering activity of Citri unshii pericarpium in hyperlipemic rats

The inhibitory effect of the MeOH extract of Citri unshii pericarpium (CU) and its fractions were tested in hyperlipemic rats using for animal models induced by high cholesterol-diet. We measured plasma levels of triglyceride, total cholesterol, low-density lipoprotein (LDL)-cholesterol and high-density lipoprotein (HDL)-cholesterol as measures of its hyperlipemic effects. We demonstrated that CU decreases plasma levels of triglyceride, total cholesterol and LDL cholesterol. There was also no elevation of plasma ALT and AST levels, which indicate CU did not cause liver injury. These results indicate that CU is a good candidate for the treatment on high cholesterol diet-induced blood circulatory disorders, obesity and hyperlipidemia.

Orange juice and hesperetin supplementation to hyperuricemic rats alter oxidative stress markers and xanthine oxidoreductase activity

Our objective was to examine the effect of orange juice and hesperetin on serum total antioxidant capacity (TAC), lipid peroxidation (MDA), uric acid and hepatic xanthine oxidase (XO) and xanthine dehydrogenase (XDH) activity in hyperuricemic rats. Experimentally hyperuricemia in rats was induced by intraperitoneal injection of potassium oxonate (250 mg/kg). Orange juice (5 ml/kg) and hesperetin (5 mg/kg) was given by oral gavage to rats for 2 weeks and biochemical data was measured. Data showed that orange juice supplementation increased serum TAC and decreased MDA concentration (p≤0.05). Orange juice also inhibited hepatic XO and XDH activity and decreased serum uric acid levels. Hesperetin, which is the main flavanone constituent in orange juice, also exhibited antioxidative and antihyperuricemic properties, but its effect was weaker than that of orange juice. Although the hypouricemic effect of allopurinol (5 mg/kg), as a positive control, was much higher than that of orange juice and hesperetin, it could not significantly change biomarkers of oxidative stress. These features of orange juice and hesperetin make them an attractive candidate for the prophylactic treatment of hyperuricaemia, particularly if these compounds are to be taken on a long-term basis.

Investigation of the radioprotective efficacy of hesperidin against gamma-radiation induced cellular damage in cultured human peripheral blood lymphocytes

The present study was aimed to evaluate the radioprotective efficacy of hesperidin (HN), a flavonone glycoside against gamma-radiation-induced cellular damage in cultured human peripheral blood lymphocytes. Different concentrations of HN (3.27, 6.55, 9.83, 13.10, 16.38 and 19.65 microM) were pre-incubated with lymphocytes for 30 min prior to gamma-irradiation [4 Gy] and the micronuclei (MN) scoring, dicentric aberration and comet assay were performed to fix the effective dose of HN against gamma-irradiation induced cellular damage. The results indicated that among all the concentrations, 16.38 microM concentration of HN showed optimum protection by effectively decreasing the MN frequencies, dicentric aberrations and comet attributes. Based on the above results, 16.38 microM concentration of HN was fixed as the effective dose to further investigate its radioprotective efficacy which was then carried out by pre-incubating lymphocytes with 16.38 microM concentration of HN, exposing the lymphocytes to different doses (1, 2, 3 and 4 Gy) of radiation and investigating radiation induced genetic damage (MN, dicentric aberration, comet assay, DNA fragmentation assay) and biochemical changes (changes in the level of enzymic and non-enzymic antioxidants, lipid peroxidation). The results indicated a dose dependent increase in both genetic damage and thiobarbituric acid reactive substances (TBARS), accompanied by a significant decrease in the antioxidant status compared to HN treated groups which modulated the toxic effects through its antioxidant potential. Thus the current study shows HN to be an effective radioprotector against gamma-radiation induced in-vitro cellular damage in lymphocytes.

Hesperidin, an antioxidant flavonoid, prevents acrylonitrile-induced oxidative stress in rat brain

Acrylonitrile (ACN) is a volatile, toxic liquid used as a monomer in the manufacture of synthetic rubber, styrene plastics, acrylic fiber, and adhesives. ACN is a potent neurotoxin. A role for free radical mediated lipid peroxidation in the toxicity of ACN has been suggested. We examined the ability of hesperidin, an antioxidant flavonoid, to attenuate ACN-induced alterations in lipid peroxidation in rat brains. The daily oral administration of ACN to male albino rats in a dose of 50 mg/kg bwt for a period of 28 days produced a significant elevation in brain lipid peroxides measured as malondialdehyde (MDA) amounting to 107%, accompanied by a marked decrease in brain-reduced glutathione (GSH) content reaching 63%. In addition, ACN administration resulted in significant reductions in the enzymatic antioxidant parameters of brain; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione-S-transferase (GST) recording 43%, 64%, 52%, and 43%, respectively. On the other hand, pretreatment with hesperidin and its coadministration with ACN once daily in a dose of 200 mg/kg bwt i.p. for 28 days ameliorated ACN-induced alterations in brain lipid peroxidation. These results suggest that hesperidin may have a beneficial role against ACN-induced oxidative stress in the brain; an effect that is mainly attributed to the antioxidant property of hesperidin.

Prophylactic effect of liposomal N-acetylcysteine against LPS-induced liver injuries

The aim of this study was to evaluate and compare the effectiveness of N-acetylcysteine (NAC) and liposomally-encapsulated NAC (L-NAC) in ameliorating the hepatotoxic effects of lipopolysaccharide (LPS). LPS, a major cell wall molecule of Gram-negative bacteria and the principal initiator of septic shock, causes liver injury in vivo that is dependent on neutrophils, platelets, and several inflammatory mediators, including tumour necrosis factor-alpha (TNF-alpha). Male Sprague-Dawley rats were pretreated intravenously with saline, plain liposomes (dipalmitoylphosphatidylcholine [DPPC]), NAC (25 mg/kg body weight), or L-NAC (25 mg/kg NAC body weight) and 4 h later were challenged intravenously with LPS (Escherichia coli O111:B4, 1.0 mg/kg body weight); animals were killed 20 h post-LPS challenge. Hepatic cell injury was evaluated by measuring the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in plasma. LPS-induced activation of the inflammatory response was evaluated by measuring the levels of myeloperoxidase activity and chloramine concentration in liver homogenates as well as TNF-alpha levels in plasma. The hepatic levels of lipid peroxidation products and non-protein thiols (NPSH) were used to assess the extent of involvement of oxidative stress mechanisms. In general, challenge of animals with LPS resulted in hepatic injuries, activation of the inflammatory response, decreases in NPSH levels and increases in the levels of lipid peroxidation products (malondialdehyde and 4-hydroxyalkenals). Pretreatment of animals with NAC or empty liposomes did not have any significant protective effect against LPS-induced hepatotoxicity. On the other hand, pretreatment of animals with an equivalent dose of L-NAC conferred protection against the liver injuries induced following LPS challenge. These data suggest that NAC when delivered as a liposomal formulation is a potentially more effective prophylactic pharmacological agent in alleviating LPS-induced liver injuries.

Antioxidant properties of hesperidin in nicotine-induced lung toxicity

Nicotine, the principal alkaloid in tobacco, is generally considered to be an active pharmacological agent responsible for lung-related disorders. The actions of nicotine have been extensively investigated in animal and variety of cell systems. Nicotine is known to induce the lipid peroxidation by producing reactive oxygen species and reactive nitrogen species. In the present study, we have investigated the effect of hesperidin on nicotine toxicity. The parameters studied were marker enzymes and antioxidant status in blood, tissues, BAL (bronchoalveolar lavage cells) and BALF (bronchoalveolar lavage fluid). Lung damage was induced by subcutaneous injection of nicotine at a dosage of 2.5 mg/kg body weight for 5 days a week. Hesperidin was administered orally at a dose of 25 mg/kg body weight. The results showed an increase in the level of marker enzymes and decrease in the antioxidant status in nicotine-treated rats. Hesperidin treatment resulted in a decreased level of all the marker enzymes and the antioxidant status was brought back to near normal. Thus the study shows that hesperidin offers protection against the lung damage caused by nicotine.

Hesperidin inhibits expression of hypoxia inducible factor-1 alpha and inflammatory cytokine production from mast cells

The citrus unshiu peel has been used traditionally as a medicine to improve bronchial and asthmatic conditions or cardiac and blood circulation in Korea, China, and Japan. Here, we report the effects of citrus unshiu peel water extract (CPWE) on the phorbol myristate acetate (PMA)+calcium ionophore A23187-induced hypoxia-inducible factor-1alpha (HIF-1alpha) activation and inflammatory cytokine production from the human mast cell line, HMC-1 cells. We compared CPWE with hesperidin, a common constituent of citrus unshiu. CPWE and hesperidin inhibited the PMA+A23187-induced HIF-1alpha expression and the subsequent production of vascular endothelial growth factor (VEGF). In addition, CPWE suppressed PMA+A23187-induced phosphorylation of the extracellular signal-regulated kinase (ERK). We also show that the increased cytokines interleukin (IL)-1beta, IL-8, and tumor necrosis factor (TNF)-alpha level was significantly inhibited by treatment of CPWE or hesperidin. In the present study, we report that CPWE and hesperidin are inhibitors of HIF-1alpha and cytokines on the mast cell-mediated inflammatory responses.

Quality control and discrimination of pericarpium citri reticulatae and pericarpium citri reticulatae viride based on high-performance liquid chromatographic fingerprints and multivariate statistical analysis

High-performance liquid chromatographic (HPLC) fingerprints of pericarpium citri reticulatae (PCR) and pericarpium citri reticulatae viride (PCRV) were firstly measured for deliberately collected 39 authentic samples and 21 commercial samples. Both correlation coefficients of similarity for chromatograms and absolute peak areas of characteristic compounds were calculated for quantitative expression of the HPLC fingerprints. After principal component analysis (PCA) successfully distinguished the 'mixed peels' samples from authentic samples, partial least squares-linear discrimination analysis (PLS-LDA) was then effectively applied to class separation between authentic PCR and PCRV. Furthermore, the unequivocally determined compounds, hesperidin, nobiletin and tangeretin, were screened out by loadings plots of PCA and PLS-LDA. The results indicated that they could be used as chemical markers for discrimination among different groups of samples. The proposed method shows an efficient strategy for quality control of PCR and PCRV, which cannot only distinguish the 'mixed peels' but also discriminate authentic PCR and PCRV. This method has potential perspective for quality control of traditional Chinese medicine (TCM).