Hepatoprotective effect of taxifolin on cyclophosphamide-induced oxidative stress, inflammation, and apoptosis in mice: Involvement of Nrf2/HO-1 signaling.

Taxifolin (TA) is a natural flavonoid found in many foods and medicinal plants with well-documented antioxidant and anti-inflammatory properties. Cyclophosphamide (CP) is an effective antineoplastic and immunosuppressive agent; however, it is associated with numerous adverse events, including hepatotoxicity. Herein, we aimed to investigate the potential protective effects of TA using a mouse model of CP-induced hepatotoxicity. Mice were co-treated with TA (25 and 50 mg/kg, orally) and CP (30 mg/kg, i.p.) for 10 consecutive days and sacrificed 24 hours later. CP induced increased transaminases (ALT and AST), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) paralleled with pronounced histopathological alterations in the liver. Moreover, hepatic tissues of CP-injected mice showed increased malondialdehyde (MDA), protein carbonyl, and nitric oxide (NO) levels, accompanied by decreased antioxidant defenses (glutathione [GSH], superoxide dismutase [SOD], and catalase [CAT]). Livers of CP-injected mice also showed increased inflammatory response (nuclear transcription factor kappa-B [NF-κB] p65 activation, increased levels of proinflammatory cytokines tumor necrosis factor alpha [TNF-α], interleukin 1 beta [IL-1ß], and IL-6) and apoptosis (decreased Bcl-2 and increased Bax and caspase-3 expression levels). Remarkably, TA ameliorated markers of liver injury and histological damage in CP-injected mice. TA treatment also attenuated numerous markers of oxidative stress, inflammation, and apoptosis in the liver of CP-injected mice. This was accompanied by increased nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) expression in the liver tissues of CP-injected mice. Taken together, this study indicates that TA may represent a promising new avenue to prevent/treat CP-induced hepatotoxicity and perhaps other liver diseases associated with oxidative stress and inflammation.

A flavonoid-rich fraction of Monolluma quadrangula inhibits xanthine oxidase and ameliorates potassium oxonate-induced hyperuricemia in rats.

Hyperuricemia represents a risk factor for the progression of chronic kidney disease. Oxidative stress and inflammation are implicated in the mechanisms underlying hyperuricemia-mediated kidney injury. Monolluma quadrangula possesses several beneficial effects; however, its effect on hyperuricemia has not been investigated. This study evaluated the renoprotective and xanthine oxidase (XO) inhibitory activity of M. quadrangula in hyperuricemic rats. Phytochemical investigation revealed the presence of six known flavonoid isolated for the first time from this species. The rats received M. quadrangula extract (MQE) and potassium oxonate (PO) for 7 days. In vitro assays showed the radical scavenging and XO inhibitory activities of MQE, and in silico molecular docking revealed the inhibitory activity of the isolated flavonoids towards XO. Hyperuricemic rats showed elevated serum uric acid, creatinine, urea, and XO activity, and renal pro-inflammatory cytokines, MDA and NO, and decreased GSH, SOD, and catalase. MQE ameliorated serum uric acid, urea, creatinine, and XO activity, and renal pro-inflammatory cytokines. In addition, MQE attenuated renal oxidative stress, enhanced antioxidants, downregulated URAT-1, and GLUT-9 and upregulated OAT-1 in PO-induced rats. In conclusion, M. quadrangula attenuated hyperuricemia and kidney impairment by suppressing XO activity, oxidative stress and inflammation, and modulating urate transporters.

Activation of aryl hydrocarbon receptor signaling by gallic acid suppresses progression of human breast cancer in vitro and in vivo.

BACKGROUND: Despite the significant advances in diagnosis and treatment, breast cancer remains the most common malignancy and the second cause of death in women. Increasingly, preclinical evidence has suggested aryl hydrocarbon receptor (Ahr), a ligand activated transcription factor, a promising therapeutic target in breast cancer. PURPOSE: This study aims at screening a number of phenolic compounds to identify an Ahr ligand with suppressive effects on human breast cancer. METHODS: Potential interactions between Ahr and phenolic compounds were predicted in silico, and physical interaction was examined by ligand competitive binding in vitro. The MDA-MB-231 and T47D breast cancer cell lines were used to examine the expression of Ahr downstream genes and progression of breast cancer cells in vitro. Binding of Ahr/Ahr nuclear transporter (Arnt) complex to the xenobiotic-responsive element (XRE)-box was examined by DNA-protein interaction (DPI)-ELISA, promoter activity was assessed using luciferase reporter system, and RNA interreference was carried out using electroporation. The real-time PCR and/or immunoblotting were used to quantify gene expressions. Tumor growth in vivo was assessed using a murine orthotopic model. RESULTS: A combined computational modeling and in vitro approaches identified gallic acid (GA) as an Ahr ligand with agonistic properties. It induced binding of Ahr/Arnt to the XRE-box, enhanced the promoter activity and expression of Ahr downstream genes including cytochrome P450 1A1 (CYP1A1), and SRY-related HMG-box4 (SOX4)-targeting miR-212/132 cluster and miR-335 in both MDA-MB-231 and T47D cells. GA increased apoptosis while decreased proliferation, migration and invasion capacities of breast cancer cells in an Ahr-dependent fashion. Furthermore, it reduced the levels of B-cell lymphoma 2 (BCL-2), cyclooxygenase-2 (COX-2) and SOX4, while selectively increased that of tumor protein 53 (P53), in an Ahr-dependent and -independent fashions. In an in vivo orthotopic model, GA activated Ahr signaling and reduced the growth of breast cancer cells. CONCLUSION: We identified GA as an Ahr phenolic ligand, and provided evidence on the role of Ahr in mediating its anti-breast cancer effects, indicating that GA, and possibly other phenolic compounds, have important therapeutic implications in human breast cancer through activation of Ahr signaling.

Herbs as thermoregulatory agents in poultry: An overview.

The adverse effect of increased environmental temperature during summer season on avian industry has received great global concern. High temperature leads to severe economic loss in poultry production, because it is considered as valuable stress factor. Several practical methods were used to alleviate the adverse impact of increased temperature; among them were dietary modifications. So, several types of herbs are supplemented to reduce the deleterious influences of thermal stress altitudes in various animals, and even to prevent their adverse impacts. Therefore, sustainable supports for dietary modification based on herbs supplementations are largely needed, particularly when consider the additional advantages of herbs such as availability, actual efficiency, low cost, as well as their free from residual impact and antibiotic resistance. Numerous types of herbs were concluded to their efficient properties by poultry breeders to overcome a variety of the harmful effects of high ambient temperature. The present article deliberates the different practical applications of several members of the traditional herbal wealth to improve the general health state of poultry particularly as thermoregulatory and immunomodulatory agents, and for countering the heat stress-associated immunosuppressive effects. Additionally, the antioxidant activity of herbal growth promoters and their influence on improvement of production performances were a special aim of this review. The reported information will be helpful for improvement of general production and health status of birds reared under the heat stress via enhancement of immune response and stress tolerance, and popularizes usage of herbs amongst poultry producers.

Spirulina platensis ameliorates the sub chronic toxicities of lead in rabbits via anti-oxidative, anti- inflammatory, and immune stimulatory properties.

Lead acetate (Pb) is an oldest and widespread environmental toxicant that led to cumulative injury in humans and all living organisms through induction of oxidative stress. Spirulina platensis (SP) is a cyanobacteria with strong antioxidant, anti-inflammatory, and immune stimulatory effects. In this study, the ameliorative effect of SP was evaluated against the dietary sub chronic lead toxicities in rabbits. A total number of 75 male New Zealand rabbits were allocated randomly into 5 groups; the first group feed on basal diet alone and served as control group, the second group feed on basal diet + 100 mg Pb /kg diet, the third, fourth, and the fifth groups feed on basal diet + 100 mg Pb /kg diet + SP (0.5, 1, or 1.5 g/kg diet; respectively), the experiment was extended for 8 weeks. Results revealed a significant improvement in some of growth parameters like final body weight and daily weight gain, blood parameters in rabbits treated with SP at level 1.5 g/kg diet followed by those receiving SP 1 g/kg diet. However, a significant decrease in blood parameters, liver function, renal parameters, lipid profiles, oxidative parameters (malondialdehyde and protein carbonyl), heart indices (creatine phosphokinase, creatine kinase-muscle/brain, lactate dehydrogenase), total Pb residues in muscles, and area percent of nuclear factor kappa b immune expression were reported in groups supplemented with different levels of SP. Pathologic analysis of liver, kidneys, and heart revealed moderate to severe degenerative and necrotic changes in Pb- exposed rabbits, which is ameliorated with supplementation of SP in different levels. Conclusively, dietary supplementation of SP at different levels attenuated the cumulative effect of lead in rabbits in dose-dependent manner; this attenuation may be attributed to its anti-oxidative, anti-inflammatory, as well as its immune stimulant effect.

Pathophysiological mechanisms of diabetic cardiomyopathy and the therapeutic potential of epigallocatechin-3-gallate.

Cardiovascular complications are considered one of the leading causes of morbidity and mortality among diabetic patients. Diabetic cardiomyopathy (DCM) is a type of cardiovascular damage presents in diabetic patients independent of the coexistence of ischemic heart disease or hypertension. It is characterized by impaired diastolic relaxation time, myocardial dilatation and hypertrophy and reduced systolic and diastolic functions of the left ventricle. Molecular mechanisms underlying these pathological changes in the diabetic heart are most likely multifactorial and include, but not limited to, oxidative/nitrosative stress, increased advanced glycation end products, mitochondrial dysfunction, inflammation and cell death. The aim of this review is to address the major molecular mechanisms implicated in the pathogenesis of DCM. In addition, this review provides studies conducted to determine the pharmacological effects of (-)-epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, focusing on its therapeutic potential against the processes involved in the pathogenesis and progression of DCM. EGCG has been shown to exert several potential therapeutic properties both in vitro and in vivo. Given its therapeutic potential, EGCG might be a promising drug candidate to decrease the morbidity and mortality associated with DCM and other diabetes complications.

Ginger alleviates hyperglycemia-induced oxidative stress, inflammation and apoptosis and protects rats against diabetic nephropathy.

Oxidative stress plays a major role in the development and progression of diabetic nephropathy (DN). In this study, the potential protective effect of ginger (Zingiber officinale) rhizome extract on hyperglycemia-induced oxidative stress, inflammation and apoptosis was investigated. An experimental diabetic rat model was induced by intraperitoneal injection of streptozotocin. Diabetic rats were treated orally with 400 or 800 mg/kg/day Z. officinale extract for six weeks. Diabetic animals exhibited elevated blood glucose levels and glycated hemoglobin (HbA1c) with altered lipid profile. Blood urea nitrogen, serum creatinine and urea, and urine albumin levels were significantly increased in diabetic rats. Treatment with Z. officinale ameliorated hyperglycemia, hyperlipidemia and kidney function. In addition, Z. officinale minimized the histological alterations in the kidney of diabetic rats. Chronic hyperglycemia resulted in a significant increase in malondialdehyde, protein carbonyl, pro-inflammatory cytokines, cytochrome c and caspase-3 in the kidney of rats. Z. officinale extract significantly attenuated oxidative stress, inflammation and apoptosis, and enhanced antioxidant defenses in the diabetic kidney. In conclusion, this study strongly suggests that Z. officinale rhizome extract exerts a protective role against diabetes-induced renal injury by ameliorating oxidative stress, inflammation and apoptosis.

Epigallocatechin-3-gallate protects against diabetic cardiomyopathy through modulating the cardiometabolic risk factors, oxidative stress, inflammation, cell death and fibrosis in streptozotocin-nicotinamide-induced diabetic rats.

The potential protective effect of epigallocatechin-3-gallate (EGCG) on type 2 diabetes-induced heart injury was investigated. A rat model of diabetes was achieved by injection of nicotinamide (100mg/kg, i.p), 20min before the administration of streptozotocin (55mg/kg, i.p.). After confirmation of diabetes, EGCG (2mg/kg, p.o.) was administrated on alternate days for one month. Treatment of diabetic rats with EGCG showed a remarkable reduction in glucose, glycosylated hemoglobin, HOMA-IR and lipid profile levels with an elevation in insulin levels, indicating its antihyperglycemic and antidyslipidemic actions. EGCG treatment also suppressed the increase in the levels of superoxide, 4-hydroxynonenal and protein carbonyl, whereas it increased the content of glutathione and the activities of superoxide dismutase and catalase in heart of diabetic rats, indicating its antioxidant capacity. In addition, EGCG improved heart function of diabetic rats as evidenced by a remarkable reduction in troponin T level and creatine kinase-MB, lactate dehydrogenase and aspartate aminotransferase activities in the serum. Oral administration of EGCG for one month after diabetes induction significantly protected the increase in serum levels of pro-inflammatory cytokines (IL-1 ß, IL-6 and TNF-α) and adhesion molecules (ICAM-1 and VCAM-1), suggesting its anti-inflammatory potential. Furthermore, EGCG hampered the mitochondrial apoptotic pathway through increasing Bcl-2 level and decreasing p53, Bax, cytochrome c and caspase-3 and 9 levels in hearts of diabetic rats, indicating its anti-apoptotic action. Diabetic rats treated with EGCG also exhibited decreased level of DNA damage in the myocardium. The histological examinations indicated the cardioprotective effect of EGCG against harmful impact of diabetes. Therefore, these findings suggest that EGCG has a protective effect on the heart affected by type 2 diabetes and recommend it as a complementary supplement for diabetic patients.