Soha M. Hamdy

The role of glutathione S- transferase M1 and T1 gene polymorphisms and oxidative stress-related parameters in Egyptian patients with essential hypertension.

BACKGROUND Essential hypertension is a complex, multifactorial, polygenic disease in which the underlying genetic components remain unknown. Glutathione S-transferase (GST) enzyme is involved in detoxification of reactive oxygen species. This study aimed to investigate GSTM1 and GSTT1 gene polymorphisms in Egyptian essential hypertensive patients and their relationship with oxidative stress-related parameters. METHODS The study included 40 newly-diagnosed, untreated, essential hypertensive patients and 40 normotensive subjects. Plasma levels of malondialdehyde (MDA), and nitrate/nitrite and erythrocyte reduced glutathione (GSH), activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione S-transferase (GST) were measured. Genotyping for GSTM1 and GSTT1 was performed. RESULTS The frequency of GSTM1+ve/GSTT1+ve in hypertensives (5%) was lower than in normotensives (37.5%).The frequency of GSTM1-ve/GSTT1-ve was elevated in hypertensives (35%) as compared to normotensives (7.5%). Plasma MDA was higher and nitrate/nitrite was lower in hypertensives than in normotensives. Erythrocyte GSH, activities of CAT, SOD, GSH-Px, and GST of hypertensives were lower than normotensives. Moreover, GST activity was lower in subjects with GSTM1-ve/GSTT1-ve than in those with GSTM1+ve/GSTT1+ve. In hypertensives, both systolic and diastolic blood pressures were negatively correlated with activities of CAT, GSH-Px, and GST. CONCLUSIONS GSTM1-ve/GSTT1-ve is a potential genetic factor to predict development of essential hypertension and permit early therapeutic intervention. The significant association between blood pressure and oxidative stress-related parameters indicates the pathogenic role of oxidative stress in hypertension. Antioxidants could be useful in the management of essential hypertension to prevent progressive deterioration and target organ damage however, further studies involving long-term clinical trials may help to assess the efficacy of these therapeutic agents.

Serum visfatin as a non-traditional biomarker of endothelial dysfunction in chronic kidney disease: An Egyptian study

BACKGROUND Endothelial dysfunction (ED) is closely linked to cardiovascular disease and outcome in patients with chronic kidney disease (CKD). Visfatin is an adipocytokine that recently generated much interest; however, its role in CKD remains to be clarified. This study aimed to assess visfatin in correlation with markers of ED and inflammation in Egyptian patients with CKD. METHODS The study included 40 non-diabetic, clinically stable CKD patients and 20 healthy volunteers. Serum levels of visfatin, markers of ED (intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)) and markers of inflammation (interleukin-6 (IL-6), and C-reactive protein (CRP)) were measured. Endothelial function was evaluated using brachial artery flow-mediated dilatation (FMD). RESULTS Serum visfatin, ICAM-1, VCAM-1, CRP, and IL-6 levels were significantly elevated and FMD% was decreased in CKD patients as compared to controls. Visfatin correlated positively with ICAM-1, VCAM-1, CRP, and IL-6 and negatively with FMD% in CKD patients. In a multiple regression model, visfatin was strongly and independently associated with FMD (Beta=-0.02, P<0.001) in CKD patients. CONCLUSIONS Serum visfatin is strongly associated with endothelial adhesion molecules and FMD%, suggesting that visfatin is an important promising biomarker for prediction of ED and future cardiovascular risk in CKD patients. Moreover, the relationship between visfatin and IL-6 indicates that circulating visfatin may reflect the sub-clinical inflammatory status. Thus, visfatin might be involved in the complex interactions between ED, inflammation, and atherosclerosis and their major clinical consequences; however, further prospective studies are required to prove this hypothesis.

Prevention of rat breast cancer by genistin and selenium.

Breast cancer is the second leading cause of cancer death among women and the third most common cancer. In this study, we investigated the chemoprevention efficacy of each of soy genistin, selenium or a combination of them against breast cancer. Seventy-five female rats were divided into five groups : control group (I); 7,12-dimethylbenz(a)anthracene (DMBA) group (II); DMBA treated with genistin group (III); DMBA treated with selenium group (IV); and DMBA treated with genistin combined with selenium group (V). The treatments were daily administered for 3 months. There were a significant decrease in body weight and serum total antioxidant, while a significant elevation in serum total sialic acid, carcinoembryonic antigen, prolactin, estradiol, nitric oxide, and malondialdhyde of DMBA injected rats compared with control group. Administration of genistin and selenium was associated with decreasing levels of tumorigenicity, endocrine derangement, and oxidative stress. Formation of breast carcinoma in DMBA-induced rats and abnormal changes were ameliorated in the rats treated with genistin/selenium or genistin alone. Supplementation of genistin alone or with selenium provided antioxidant defense with high-potential chemopreventive activity against DMBA-induced mammary tumors more than selenium alone.

Impact of Nitric Oxide Synthase Glu298Asp Polymorphism on the Development of End-Stage Renal Disease in Type 2 Diabetic Egyptian Patients

Abstract Background: Nitric oxide is an important regulator of renal hemodynamics. This study aimed to investigate the role of endothelial nitric oxide synthase (eNOS) gene polymorphism in type 2 diabetic patients with end-stage renal disease (ESRD) and to elucidate any alteration of nitric oxide synthase (NOS) activity caused by this polymorphism. Methods: The study included 80 patients with type 2 diabetes of >10 years duration (40 with diabetes-derived ESRD, 40 without nephropathy) and 20 healthy controls. Plasma nitrate/nitrite level, and serum NOS activity were measured and eNOS Glu298Asp genotypes were determined. Results: The frequency of Glu/Glu (GG) genotype in diabetics with ESRD was lower than controls. However, the frequency of Asp/Asp (TT) genotype was increased in diabetics with ESRD as compared to those without nephropathy and controls. Diabetics with ESRD had significantly lower nitrate/nitrite level and NOS activity than those without nephropathy. Diabetic patients with TT genotype are at a significant risk for ESRD. Moreover, subjects carrying TT genotype had lower nitrate/nitrite level and NOS activity than those carrying GG genotype. In diabetics with ESRD, creatinine clearance was positively correlated with both nitrate/nitrite level and NOS activity. Conclusions: These results imply that TT genotype of eNOS may be associated with an increased risk of ESRD in Egyptian type 2 diabetics. It could represent a useful genetic marker to identify diabetics at high risk for the development of ESRD. However, larger future prospective studies are required to confirm the role of eNOS gene polymorphism in the progression of diabetic nephropathy to ESRD.

Immobilization of Urease on (HEMA/IA) Hydrogel Prepared by Gamma Radiation

In the present study, the copolymeric hydrogels based on 2-hydroxyethyl methacrylate (HEMA) and itaconic acid (IA) were synthesized by gamma radiation induced radical polymerization, in order to examine the potential use of these hydrogels in immobilization of Citrullus vulgaris urease. Gelation and Swelling properties of PHEMA and copolymeric P (HEMA/IA) hydrogels with different IA contents (96.5/3.5, 94.4/5.6 and 92.5/7.5 mol) were studied in a wide pH range. Initial studies of so-prepared hydrogels show interesting pH sensitivity in swelling and immobilization. C. vulgaris urease was immobilized on HEMA/IA (92.5/7.5) at 6 kGy with 41.3% retention of activity. The properties of free and immobilized urease were compared. Immobilized urease maintained a higher relative activity than free urease at both lower and higher pH levels, indicating that the immobilized urease was less sensitive to pH changes than the free urease. The Km value of the immobilized urease was approximately 2 times higher than that of the free urease. Temperature stability was improved for immobilized enzyme. The free form exhibited a loss about 80% of activity upon incubation for 15 min at 80°C. The influence of various heavy metal ions at the concentration of l mM was improved after enzyme immobilization. The immobilization of C. vulgaris urease on HEMA/IA (92.5/7.5) at 6 kGy showed a residual activity of 47 % after 4 reuses.

Nitric Oxide Synthase and Oxidative Stress: Regulation of Nitric Oxide Synthase

Nitric oxide has been found to play an important role as a signal molecule in many parts of the organism as well as a cytotocic effector molecule of nonspecific immune response. Nitric oxide is very important functions both in helminthes and mammalian hosts. Nitric oxide may react with proteins and nucleic acids. In addition to binding to heme groups, e.g. of guanylate cyclase, hemoglobin, and cytochrome C oxidase, NO may react with nucleophilic centers like sulfur, nitrogen, oxygen and aromatic carbons. The prime target for covalent binding of NO to a functional groups in proteins under physiological condition in the presence of oxygen are SH groups. The intra-mitochondrial reaction of NO with superoxide anion yields peroxynitrite, which irreversibly modifies susceptible targets within the mitochondria, inducing oxidative and/or nitrative stresses. The signal molecule of NO is synthesized by constitutive nitric oxide synthase (cNOS). The killer molecule NO is synthesized by inducible NOS (iNOS). There is no signal or killer NO – it depends on the environments and partners involved – be very careful in that. Yes, the production is regulated in different ways. Inducible NOS is induced by numerous inflammatory stimuli, including endotoxin, cytokines and excretory/secretory products (ESP) of helminthes. ESP directly interact with the immune system and modulate host immunity. Nitric oxide is a highly reactive and unstable free radical gas that is produced by oxidation of Larginine by oxygen and NADPH as electron donor to citrulline mediated by a family of homodimer named nitric oxide synthase. In addition to Larginine-NO pathway, L-arginine is also metabolized to L-ornithine and urea by arginase enzyme. A side from blocking NO synthesis by depleting the cell of substrate for NOS, the arginase-mediated removal of Larginine inhibits the expression of inducible NOS (iNOS) by repressing the translation as well as the stability of iNOS protein. Furthermore, arginase may inhibit iNOS-mediated NO production through the generation of urea.

Biosynthesis, optimization and potential textile application of fungal cellulases/xylanase multifunctional enzyme preparation from Penicillium sp. SAF6

Abstract The main task of the present work is to search for fungal strains isolated from agricultural soil with the potential to produce cellulases/xylanase enzyme preparation for bio-finishing of textiles. The most potent fungal strain (SAF6) was subjected to molecular identification using 18 SrRNA and was identified as Penicillium sp. SAF6 with the novel accession number of KM222497. Factors affecting the produced mixed enzyme activity were investigated. The optimum conditions for achieving maximum activity of the cellulases (FPase, CMCase and β-glucosidase) in addition to xylanase were the initial culture pH media 5, yeast extract (1.5gN/L), medium-to-air ratio (1:5) for FPase and CMCase and (1:10) for β-glucosidase, at 30 °C for 8 days incubation period. Potential application of the prepared crude enzyme in bio-finishing of cellulosic substrates, namely, bleached cotton, linen and indigo dyed fabrics were explored. Using the multi-component enzyme at appropriate dosage and conditions brought about a significant improvement and surface modification of the treated cotton substrates.

Protective effect of Hesperidin and Tiger nut against Acrylamide toxicity in female rats

Phytochemicals that have antioxidant effect play important role in protection against several diseases in humans. This study was carried out to evaluate the efficacy of hesperidin and tiger nut against the early changes that may be related to the toxicity of acrylamide in female rats. 72 Sprague Dawley female rats were divided into six groups (12 rat/group): control group (I); hesperidin (HES) treated group (II); tiger nut (TN) treated group (III); Acrylamide (ACR) treated group (IV); HES-ACR treated group (V); and TN-ACR treated group (VI). There was a significant increase in the levels of serum carcino embryonic antigen (CEA), malondialdehyde (MDA), protein carbonyls (CO), ALT, AST, LDH, urea and creatinine while no significant changes of serum total sialic acid, progesterone (prog) and estradiol (E2) levels, and significant decreases of body weights, catalase (Cat) activity, superoxide dismutase (SOD) activity, reduced glutathione (GSH) level, and glutathione peroxidase (GSH-Px) activity of ACR treated group compared with the control. Our results suggested that supplementation of a diet with hesperidin provided antioxidant defense more significant than tiger nut against the toxicity of ACR in breast, liver and kidney tissues.

Hesperidin and tiger nut reduced carcinogenicity of DMBA in female rats

Nutritional studies recommend the regular consumption of fruits and vegetables to favor a healthy quality of life. This study was carried out to evaluate the efficacy of hesperidin and tiger nut against the carcinogenic activity of DMBA in female rats. 72 adult Sprague Dawley female rats were divided equally into six groups: control group (I); Hesperidin treated group (II); Tiger Nut treated group (III); DMBA treated group (IV); HES-DMBA treated group (V); and TN-DMBA treated group (VI). There was a significant increase in serum levels of carcinoembryonic antigen, total sialic acid, progesterone, estradiol, ALT, AST, LDH, urea and creatinine, and significant decrease in reduced glutathione level, superoxide dismutase, catalase and glutathione peroxidase activities of DMBA treated group compared to control. In conclusion, our results suggested that supplementation of diets with hesperidin provided antioxidant and chemoprotective activities more significant than tiger nut against the toxicity of DMBA in breast, liver and kidney tissues.

Comparative Study for Biosorption of Heavy Metals from Synthetic Wastewater by Different Types of Marine Algae

Pollution by heavy metal ions is one of the major environmental problems in many countries. In this study, four different species of dried marine macroalgae, Ulva lactuca, Jania rubens, Pterocladia capillacea and Colpomenia sinosa were used for the removal of toxic heavy metal ions Pb+2, Cd+2 and Ni+2 from synthetic wastewater. In general, the highest efficiency of metal ion bioremoval was recorded for red alga J. rubens followed by C. sinosa and the lowest one was recorded for U. lactuca, with mean removal values of 91%, 89% and 85%, respectively. The effect of several parameters such as contact time, algal dose, effect of pH, and initial concentration of metal ions on the adsorption process was estimated. The optimum adsorption was found to occur at pH 5.0, contact time 60 min, adsorbent dose 20 g/L and initial concentration 40 mg/L. This work confirms the potential use of red macroalga J. rubens as an inexpensive and efficient alternative technology, for sequestering heavy metal ions from wastewater.