Hebatallah Husseini Atteia

Fenugreek seed powder mitigates cadmium-induced testicular damage and hepatotoxicity in male rats.

Cadmium is a potential environmental and industrial pollutant affecting human tissues and organs including liver and testes. The protective role of fenugreek seed powder (FSP) was investigated in male rats subjected to cadmium-induced testicular injury and hepatic dysfunction. Testicular damage and hepatotoxicity were induced by oral administration of cadmium chloride (5 mg/kg body weight, once a day) for 7 weeks. FSP was given at 5% w/w in chow diet for 8 weeks, starting 1 week before cadmium administration. FSP intake significantly increased serum testosterone level and testis weight that were reduced by cadmium. FSP also compensated deficits in hepatic and testicular antioxidant defense system, interleukin-4 and nitric oxide levels, reduced serum liver function enzyme activities and suppressed lipid peroxidation in hepatic and testicular tissues resulted from cadmium administration. Additionally, FSP attenuated the cadmium-induced elevations in hepatic and testicular tumor necrosis factor-α and transforming growth factor-beta1 levels as well as cadmium deposition and hydroxyproline content. The protective effect afforded by FSP was mainly due its antioxidant, antifibrotic and anti-inflammatory effects. In conclusion, the results of the present work indicated that FSP may represent a promising medicinal herb to protect hepatic and testicular tissues from the detrimental effects of cadmium.

Inflammation, oxidative stress and apoptosis cascade implications in bisphenol A-induced liver fibrosis in male rats

Bisphenol A (BPA) is a key monomer in the production of plastics. It has been shown to be hepatotoxic. Inflammation and oxidative stress are closely linked with liver fibrosis, the major contributing factor to hepatic failure. Therefore, the aim of this study was to evaluate the impact of chronic exposure to BPA on the development of hepatic fibrosis in male rats and to determine the cross‐talk between the hepatic cytokine network, oxidative stress and apoptosis. For this purpose, 30 male Wistar albino rats were divided into three equal groups as follows: the first group was given no treatment (normal control group); the second group was given corn oil once daily by oral gavage for 8 weeks (vehicle control group); and the third group received BPA (50 mg/kg body weight/day, p.o.) for 8 weeks. BPA administration induced liver fibrosis as reflected in an increase in serum hepatic enzymes activities, hepatic hydroxyproline content and histopathological changes particularly increased collagen fibre deposition around the portal tract. In addition, there was inflammation (as reflected in increase in interleukin‐1beta ‘IL‐1β’, decrease in interleukin‐10 ‘IL‐10′ serum levels and increase in IL‐1β/IL‐10 ratio), oxidative stress (as reflected in increase in malondialdehyde (MDA) level, reduction in reduced glutathione (GSH) content and inhibition of catalase (CAT) activity) and apoptosis [as reflected in an increase in caspase‐3 level and a decrease in numbers of B‐cell lymphoma 2 (BCL2)‐immunopositive hepatocytes]. Interestingly, BPA had an upregulating effect on an extracellular matrix turnover gene [as reflected in matrix metalloproteinase‐9 (MMP‐9)] and a downregulating effect on its inhibitor gene [as reflected in tissue inhibitor of matrix metalloproteinase‐2 (TIMP‐2)] expression. Thus, the mechanism by which BPA induced liver fibrosis seems to be related to stimulation of the inflammatory response, along with oxidative stress, the apoptotic pathway and activation of extracellular matrix turnover.

Sildenafil citrate attenuates the deleterious effects of elevated ammonia

Abstract Ammonia is a bi-product of protein metabolism in the body. It is able to cross the blood-brain barrier and elevated ammonia levels are toxic to the brain. Rats with hyperammonemia showed impaired learning ability and impaired function of the glutamate-nitric oxide-cyclic guanosine monophosphate (glutamate-NO-cGMP) pathway in the brain. Chronic treatment with sildenafil restored learning ability. We therefore tested the hypothesis that sildenafil has a protective effect on the brains of hyperammonemic rats. Hyperammonemia was induced in male rats by daily intraperitoneal (i.p.) injection of ammonium chloride (100 mg/kg body weight) for 8 weeks. Sildenafil citrate was administered intraperitoneally (10 mg/kg body weight/3 days) for 8 weeks. Treatment with sildenafil resulted in a significant reduction in plasma liver enzymes, lipid profile as well as brain lipid peroxidation and caspase-3 mRNA. Meanwhile, plasma NO as well as cGMP, antioxidants and endothelial nitric oxide synthase (eNOS) gene expression were significantly elevated in the brains of hyperammonemic rats. Our results showed that sildenafil exerts a protective effect on the brain by reversing oxidative stress during hyperammonemia and this could be due to (i) cytoprotective, antioxidant and anti-apoptotic effects (ii) increasing cGMP and enhancing the proper metabolism of fats which could suppress oxygen radical generation and thus preventing oxidative damage in the brain. The exact protective mechanism of sildenafil has to be still investigated and further studies are warranted. Consequently, therapeutic modulation of the NO/cGMP pathway might have important clinical applications to improve brain functions in patients with hyperammonemia or clinical hepatic encephalopathy.

Ameliorative effect of N‐acetyl cysteine on alpha‐cypermethrin‐induced pulmonary toxicity in male rats

Alpha‐cypermethrin (α‐CYP) is one of the most widely used insecticides. It may become an air pollutant and adversely affect the health. The present study was designed to determine whether treatment with N‐acetyl cysteine (NAC), a well‐known antioxidant, can be useful for the management of the deleterious effects of α‐CYP on lung tissues. For this purpose, thirty two male rats were divided into four different groups (eight rats for each). Group (I) gavaged with corn oil (control group), group (II) gavaged daily with NAC (150 mg kg−1 body weight), group (III) gavaged with α‐CYP (14.5 mg kg−1 body weight/day, dissolved in corn oil), group (IV) gavaged with NAC then with α‐CYP 2 h later for 12 weeks. α‐CYP significantly increased serum lactate dehydrogenase (LDH) and pulmonary malondialdehyde (MDA) levels, while decreased the activities of catalase (CAT) and superoxide dismutase (SOD) as well as reduced glutathione (GSH) content in lung. It also provoked higher levels of serum nitric oxide (NO), lung interleukin‐1 beta (IL‐1β), tumor necrosis factor‐alpha (TNF‐α), hydroxyproline (Hyp) as well as heme oxygenase‐1 (HO‐1), inducible nitric oxide synthase (iNOS) and nuclear factor‐kappa B (NF‐КB) gene expression in lung tissues. Histopathological alterations in lung with congestion, cellular infiltration, necrotic changes and thickening of inter‐alveolar septa were observed following α‐CYP administration. NAC reduced the adverse effects of α‐CYP on lung tissues and improved the histological architecture of lung since it showed antioxidant, anti‐inflammatory and antifibrotic effects on lung tissues. Our results indicate that NAC exerts a potent protective effect against α‐CYP‐induced oxidative damage and inflammation in lung tissues.

Nicotine and vascular endothelial dysfunction in female ovariectomized rats: role of estrogen replacement therapy.

Objectives  The protective effects of estrogen replacement therapy (ERT) against oxidative injury and endothelial dysfunction in the aortic tissues induced with nicotine in ovariectomized (OVX) rats were investigated.

Vitamin D3 intake as regulator of insulin degrading enzyme and insulin receptor phosphorylation in diabetic rats

Insulin-degrading enzyme (IDE, insulysin) is a rate-limiting enzyme in the insulin degradation process. It is an intracellular 110-kDa thiol zinc-metalloendopeptidase located in the cytosol, peroxisomes, endosomes and cell surface. IDE catalyzes degradation of several small proteins including insulin, amylin and β-amyloid protein. In addition, insulin clearance was expressed as a target in the treatment of type 2 diabetes given the role of hyperinsulinemia in the pathogenesis of insulin resistance. In this study, fourtyadult male Wistar albino rats were used, thirty rats received 20% fructose in drinking water (HFW) for six weeks to induce diabetes. Subsequently, these rats developed significantly higher body weights, dyslipidemia, hyperglycemia and insulin resistance compared to their controls. Significant increase in the levels of serum glucagon, IDE in liver tissue along with an inhibition of insulin receptor phosphorylation were also observed. Concurrent oral administration of vitamin D3 along with HFW resulted in significant decrease of serum glucose, total cholesterol, triacylglycerol and LDL-C levels. Vitamin D alleviated also insulin resistance, where both IDE, glucagon levels showed significant decrease along with activation of insulin receptor phosphorylation. Normal rats, received vitamin D3 only demonstrated non significant changes of the studied biomarkers. We concluded that vitamin D3 ameliorated insulin resistance and hyperinsulinemia in diabetic rat model received HFW through reduction of IDE and activation of insulin receptor phosphorylation.

Haemostatic risk factors in dyslipidemic rabbits: role of 10-dehydrogingerdione as a new hypolipemic agent

Micro and macrovascular complications occurring during hyperlipidemia are mostly attributed to haemostatic impairment and vascular endothelial dysfunction. Cholesteryl ester transfer protein (CETP) inhibitors have been emerged recently as promising hypocholesterolemic agents to confer protection against lipid-mediated atherosclerosis. Therefore, 10-dehydrogingerdione (DHGD), a novel CETP inhibitor isolated from ginger rhizomes, was selected as a natural product in the present study to illustrate its effect on haemostatic impairment associated with hyperlipidemia as compared to a currently used hypocholesterolemic agent, atorvastatin (ATOR). Rabbits were fed a high cholesterol diet (HCD) and divided into three groups. One group served as control group while the other groups received DHGD or ATOR. Dyslipidemic rabbits showed a significant increase in serum endothelin-1, ischemia modified albumin, plasminogen activator inhibitor-1, prothrombin fragments (1+2) and plasma fibrinogen along with a decrease of nitric oxide level in serum. Daily administration of ATOR or DHGD significantly decreased the aforementioned coagulation and ischemia biomarkers and increased serum nitric oxide. DHGD (natural) results seem to be more remarkable as compared to ATOR (synthetic).

Coenzyme Q10 and fish oil synergistically alleviate aluminum chloride-induced suppression of testicular steroidogenesis and antioxidant defense.

Abstract Aluminum (Al) is an environmental xenobiotic that stimulates free radical generation and hence reproductive toxicity. Coenzyme Q10 (CoQ10) effectively counteracts free radical-induced tissue damage. Omega-3 polyunsaturated fatty acids present in fish oil (FO) exert beneficial effects on reproduction in male animals. This study therefore investigated the effects of both agents on testicular dysfunction induced by aluminum chloride (AlCl3). Fifty male rats were gavaged with either 1% gum acacia (control group) or AlCl3 (34 mg/kg/day) for ten weeks. Concurrently, AlCl3-treated rats received no treatment, CoQ10 (10 mg/kg/day, p.o.), and/or FO (400 mg/kg/day, p.o.) for ten weeks. AlCl3 caused a significant decrease in serum testosterone, luteinizing hormone (LH), and follicular stimulating hormone (FSH), as well as testicular weight, antioxidant enzyme gene expression and activities, reduced glutathione, zinc, adenosine 3′,5′-cyclic monophosphate (cAMP) contents, and number of Leydig cells, along with down-regulation of 3beta-hydroxysteroid dehydrogenase (3β-HSD), 17β-HSD, steroidogenic acute regulatory protein (STAR), and cholesterol side-chain cleavage enzyme (P450scc) gene expression. However, testicular Al, malondialdehyde (MDA), and nitric oxide (NO) levels were markedly increased. Treatment with CoQ10 and FO, alone or in combined form led to an improvement in the aforementioned biomarkers. Overall, individual or combined treatment with CoQ10 and FO could ameliorate the toxic effects of AlCl3 on testicular tissues by mechanisms related to their potent antioxidant potential and stimulatory effects on steroidogenic enzymes transcription. CoQ10 seems to be better than FO regarding oxidative and nitrosative stress, Zn deficiency, and Al overload. However, FO showed more pronounced effect than CoQ10 on hormones, steroidogenic markers, and cAMP. A cocktail of both demonstrated greater protective effects on testicular tissues than monotherapy.

The Effects of Monosodium Glutamate on Thymic and Splenic Immune Functions and Role of Recovery (Biochemical and Histological study)

Monosodium glutamate (MSG), a flavor enhancer, is used in modern nutrition to improve food palatability. The objectives of the current study were to investigate the effect of MSG on thymus as well as spleen structures and functions. Also, to evaluate the possibility of recovery after cessation of administration. Adult male rats were divided into three groups: control, MSG (3 g MSG/kg body weight daily for 8 weeks by oral gavages), and Recovery (MSG for same period and then left untreated for additional 4 weeks). The results showed that MSG treatments significantly increased serum interleukin (IL)-1β as well as thymic and splenic malondialdehyde and decreased serum levels of IL-10 and also reduced glutathione (GSH) levels and both catalase and superoxide dismutase activities in the thymus and spleen. Histological examination showed that MSG induced a remarkable disruption in the lobular architecture of the thymus with marked decrease of the T lymphocytes with darkly stained nuclei and dilated blood sinusoid in the cortical region. Medullary region were enlarged and repopulated with small lymphocytes and dilated blood sinusoids. The cortical-medullary differentiation was difficult to be determined. Small sized splenic lymphatic follicles with absence of germinal centers and large congested blood vessels were also noticed. The differentiation between the red and the white pulps was indistinct. Recovery groups showed preserved thymic lobular architecture with repopulation of the cortical thymocytes enclosing the paler staining medulla .Splenic lymphatic follicles of different sizes with absence of germinal centers were noticed. Marginal zone is differentiated from the red pulp. Immunohistochemical staining of MSG group demonstrated a marked decrease in CD3-positive T-lymphocytes in both thymus and spleen that significantly increased in recovery group. Taken together, the data showed that MSG consumption may have immunotoxic effects on the thymus and spleen of adult rats which is reversible but the normal structure of the spleen would need time to be regained. It is recommended that further studies aimed at corroborating these findings be carried out.

Genetic polymorphisms of cytochrome P450 2D6 (CYP2D6) are associated with long term tramadol treatment-induced oxidative damage and hepatotoxicity

ABSTRACT Our objective was to figure out whether CYP2D6 gene polymorphisms may account for long term tramadol‐induced oxidative stress and hepatotoxicity in 60 patients receiving chronic tramadol treatment in Neurology and Rheumatology Outpatients Clinic, Zagazig University Hospitals, Egypt. As expected, CYP2D6*1 allele (wild type) frequency was significantly greater than CYP2D6*DUP, CYP2D6*4 and CYP2D6*10 alleles in both chronically tramadol‐treated and control groups. In tramadol‐treated patients, CYP2D6*DUP allele carriers followed by those carrying CYP2D6*1, displayed higher levels of urinary tramadol major active metabolite, O‐desmethyltramadol (M1) and serum lipid peroxidation along with lower levels of total antioxidants than those carrying other impaired function alleles (CYP2D6*4&*10), suggesting oxidative stress. There were also significant increases in serum hepatic damage markers including alpha‐glutathione transferase (&agr;‐GST) levels and liver function enzyme activities in *DUP and *1 carriers compared to carriers of other alleles. Moreover, we reported that in 42 patients with allele *1, tramadol caused mild to moderate hepatotoxicity (grades: 1–2) within 13–16months while in 7 patients with duplicated allele (*DUP), tramadol caused moderate to severe hepatotoxicity (grades: 2–3) within 10–11months (moderately longer period but shorter than that observed in allele *1), implying that exposure to tramadol for longer time in extensive and ultra‐rapid metabolizers may contribute to hepatotoxicity development. Overall, our results suggest that CYP2D6 gene polymorphisms, particularly enhanced or normal function of CYP2D6, may increase the vulnerability to long term tramadol‐induced hepatotoxicity through the enhancement of accumulation of tramadol bioactive metabolite (M1) and hence oxidative stress. Therefore, tramadol doses should be adjusted according to patients CYP2D6 genotyping analysis to avoid hepatotoxicity. HIGHLIGHTSCYP2D6 polymorphisms increase vulnerability to tramadol‐induced hepatotoxicity.Accumulation of tramadol metabolite and oxidative stress mediate hepatotoxicity.CYP2D6 genotyping is necessary to adjust tramadol doses to avoid hepatotoxicity.