Mohamed F. Elshal

The influence of smoking on semen quality, seminal microelements and Ca2+-ATPase activity among infertile and fertile men

OBJECTIVE Tobacco smoking is now increasing rapidly throughout the developing world and is one of the biggest threats to current and future world health. Several studies have addressed the role of cigarette smoking on semen quality, but the exact mechanisms remain inconclusive. In order to evaluate the detrimental effects of smoking on semen quality among Saudi subjects, the levels of different seminal parameters in smokers were compared to non-smokers. PATIENTS AND METHODS A total of 159 semen samples (61 smokers and 98 non-smokers) from men attending an infertility clinic for routine infertility workup were sub-grouped into fertile or infertile and were compared based on standard semen analysis (according to WHO guidelines), content of metals (magnesium, zinc and cadmium) and plasma membrane Ca(2+)-ATPase activity of sperms. RESULTS Cadmium concentration was found significantly higher in smokers than in non-smokers either in fertile or infertile group (2.9+/-0.4 vs 1.4+/-0.7; 2.9+/-0.5 vs 1.3+/-0.7 microg L(-1); respectively). Together with this increase in seminal Cd a significant decrease in Ca(2+)-ATPase activity (21.5+/-2.8 vs 33.71+/-1.2; 20.7+/-1.5 vs 35.07+/-2.9 mmol min(-1) mg(-1) protein, p<0.05), decrease in seminal zinc (109.8+/-8.1 vs 189.7+/-9.9 mg L(-1), p<0.01) and decrease in sperm motility (41.9%+/-2.9 vs 46.01%+/-2.5; 9.8%+/-2.4 vs 15.3%+/-2.7, p<0.05) were found. CONCLUSION Our data demonstrate that cigarette smoking affects both Ca(2+)-ATPase activity and motility of the spermatozoa. These effects may be attributed to increased seminal cadmium and reduced zinc concentrations.

Modulation of doxorubicin cytotoxicity by resveratrol in a human breast cancer cell line

BackgroundBreast cancer is the most common cancer in the Arab world and it ranked first among Saudi females. Doxorubicin (DOX), an anthracycline antibiotic is one of the most effective anticancer agents used to treat breast cancer. chronic cardiotoxicity is a major limiting factor of the use of doxorubicin. Therefore, our study was designed to assess the role of a natural product resveratrol (RSVL) on sensitization of human breast cancer cells (MCF-7) to the action of DOX in an attempt to minimize doxorubicin effective dose and thereby its side effects.MethodsHuman breast cancer cell line MCF-7, was used in this study. Cytotoxic activity of DOX was determined using (sulforhodamine) SRB method. Apoptotic cells were quantified after treatment by annexin V-FITC- propidium iodide (PI) double staining using flow-cytometer. Cell cycle disturbance and doxorubicin uptake were determined after RSVL or DOX treatment.ResultsTreatment of MCF-7 cells with 15 μg/ml RSVL either simultaneously or 24 h before DOX increased the cytotoxicity of DOX, with IC50 were 0.056 and 0.035 μg/ml, respectively compared to DOX alone IC50 (0.417 μg/ml). Moreover, flow cytometric analysis of the MCF-7 cells treated simultaneously with DOX (0.5 μg/ml) and RSVL showed enhanced arrest of the cells in G0 (80%). On the other hand, when RSVL is given 24 h before DOX although there was more increased in the cytotoxic effect of DOX against the growth of the cells, however, there was decreased in percentage arrest of cells in G0, less inhibition of DOX-induced apoptosis and reduced DOX cellular uptake into the cells.ConclusionRSVL treatment increased the cytotoxic activity of DOX against the growth of human breast cancer cells when given either simultaneously or 24 h before DOX.

The association of bone mineral density and parathyroid hormone with serum magnesium in adult patients with sickle-cell anaemia

Introduction Bone disorders including osteopenia and osteoporosis are a frequent cause of morbidity in sickle-cell disease (SCD). Magnesium (Mg) regulates some biological processes important in bone remodelling. We aimed to investigate whether serum Mg levels (sMg) may have an impact on bone mineral density (BMD) in sickle-cell anaemia (SCA). Material and methods Sixty adults with SCA in steady-state and 20 age- and race-matched healthy blood donors were included in the study. The BMD was evaluated with respect to minerals and biochemical indices of bone metabolism. Multivariate analysis was performed to determine the factors influencing BMD. Results The mean sMg concentration was 0.64 ±0.06 (reference range 0.7-1.2 mmol/l) for 34% of the population, and 0.86 ±0.08 mmol/l for 66%. There were significant differences between Mg groups and controls in BMD, phosphorus (PO4), parathyroid hormone (PTH) (p = 0.011, p = 0.011 and p = 0.0001 respectively) and osteocalcin (OC) (p = 0.030) levels. The sMg was found to be associated positively with serum calcium (Ca), PTH and OC (r = 0.585; r = 0.436; r = 0.351 respectively, all at p < 0.05), and negatively with PO4 (r = –0.312; p < 0.05). Multivariate analysis demonstrated that only PTH (p < 0.05) was an independent factor for BMD. Moreover, it identified sMg, OC, and CTX as independent factors for PTH (all p < 0.05). Conclusions These results indicate that serum Mg may be a co-contributing factor in causing low BMD. However, other possible aetiologies including decreased PTH and increased bone turnover certainly play a role. Based on the present data, it is prudent to monitor sMg routinely in this patient population and treat the condition whenever possible.

Reduced Dendritic Cells Expressing CD200R1 in Children with Inflammatory Bowel Disease: Correlation with Th17 and Regulatory T Cells

Loss of tolerance of the adaptive immune system towards indigenous flora contributes to the development of inflammatory bowel diseases (IBD). Defects in dendritic cell (DC)-mediated innate and adoptive immune responses are conceivable. The aim of this study was to investigate the expression of the inhibitory molecules CD200R1 and their ligand CD200 on DCs, to clarify the role of the DCs in the pathogenesis of IBD. Thirty-seven pediatric IBD patients (23 with Crohn’s disease (CD) and 14 with ulcerative colitis (UC)) with mean age 13.25 ± 2.9 years were included. Fourteen age-matched healthy pediatric volunteers (five males and nine females) served as a control group (HC). The percentage of CD11c+ myeloid dendritic cells (mDCs) and CD123+ plasmacytoid DCs (pDCs) expressing CD200R1 and CD200 were evaluated in peripheral blood using flow cytometry and were correlated with routine biochemical, serological markers, serum levels of cytokines and with the percentages of circulating regulatory T cells (Treg) and CD4+ producing IL-17 (Th17). IBD patients showed a significant decrease in the percentage of pDCs and mDCs expressing CD200R1 compared to that of HC. Patients with UC showed increased expressions of the CD200 molecule on pDCs as compared to HC. DCs expressing CD200R1 were found to be correlated positively with Treg and negatively with TH17 and erythrocyte sedimentation rate (ESR). Our findings suggest that IBD is associated with dysregulation in the CD200R1/CD200 axis and that the decrease in DCs expressing CD200R1 may contribute to the imbalance of Th17 and Treg cells and in the pathogenesis of IBD.

Analysis of CD95 and CCR7 expression on circulating CD4+ lymphocytes revealed disparate immunoregulatory potentials in systemic lupus erythematosus

Emerging data have implicated a critical role for CD4 in the pathogenesis of systemic lupus erythematosus (SLE). This study was designed to delineate the contribution of CD4+ T cells in the pathogenesis of SLE disease. Forty-four patients (3 male: 41 female) and 20 healthy volunteers (4 male: 16 female) were included in the study. CD4+ lymphocytes analysis was done using three-color flow cytometry with antibodies against human-CD95, a prototype cell death receptor, and the chemokine receptor-7 (CCR7) after gating for lymphocytes based on the forward and side scatter. Serum levels of IL-6, IL-12, IL-17, TNF-α and IL-10 cytokines were assayed using ELISA. Disease activity was assessed using the SLE disease activity index (SLEDAI). Based on the expression of CCR7 and CD95, CD4+ lymphocytes were subdivided into three particular subsets; CD4+CD95+CCR7+ cells, CD4+CD95−CCR7+ cells and CD4+CD95+CCR7− cells. Percentage of CD4+CD95+CCR7+ cell subset was significantly higher in patients with SLE with active disease (SLEDAI > 6) and inactive (SLEDAI < 6) as compared with controls (P = 0.005), and it showed a significant positive correlation with ANA titer (P = 0.01), and a negative correlation with WBCs count (P = 0.001). CD4+CD95+CCR7− cell subset was significantly higher in active SLE patients in comparison to patients with inactive disease and controls (P = 0.05, P = 0.005 respectively), and it correlates positively with SLEDAI, IL-6 and IL-17 levels (P = 0.001, 0.05, 0.01 respectively), and negatively with blood WBCs counts (P = 0.001). The third CD4+CD95−CCR7+cell subset was found significantly lower in SLE patients compared with controls, and it was found negatively correlated with IL-10, IL-6, and IL-17. The results show that CD4+CD95+subset lacking expression of CCR7 is associated with cell mediated inflammatory response as manifested by its correlation with signs of inflammation, inflammatory cytokines and disease activity index. Whereas, CD4+CD95+CCR7+ correlate more with antibody immune responses as manifested by association with serum ANA. These data suggest disparate roles of these cell subsets in the pathophysiology of SLE. A better understanding of the characteristics of CD4 cell subsets may shed light on the pathogenesis of autoimmune diseases, particularly SLE.

Cardioprotective role of tadalafil against cisplatin-induced cardiovascular damage in rats

The present study investigated the possible cardioprotective effect of tadalafil (Tad) on cisplatin (CDDP)-induced cardiac and vascular damages in rats. A total number of seventy two healthy male albino rats initially weighting between 200 and 220 g were used and randomly divided into four groups,18 rats in each. The control group received no treatment; CDDP group received a single dose of CDDP (4 mg/kg) intraperitoneal (i.p.) per week for 4 weeks the duration of the experiment; Tad group received 0.4 mg/kg BW Tad i.p. daily and Tad +CDDP group received 0.4 mg/kg BW Tad i.p. +4 mg/kg BW CDDP i.p. The results showed that Tad was able to decrease blood pressure, heart rate, levels of serum cardiac troponin (cTn-I), malondialdehyde (MDA) and increased levels of reduced glutathione (GSH) and nitric oxide (NO) in the heart homogenate sample from CDDP treated rats. Semi-quantitative analysis showed that Tad was able to decrease the histopathological scores of cardiac muscular hyalinzation and fibrosis in three sacrifices in CDDP treated rats. CDDP treated rats showed significantly increased thickening in wall of aorta with an irregular luminal layer of endothelial cell linings in three sacrifices when it was compared to other groups. Moreover, immunohistochemical labeling of α- smooth muscle actin (α-SMA) in aorta revealed significant lower scores in Tad +CDDP group when they were compared to CDDP group. In conclusion, Tad alone did not induce any harmful effects on blood pressure, selective antioxidant, peroxidation markers or cardiac histology, in addition, Tad has a cardio-protective role against CDDP.

Influence of defatted flaxseed diet on insulin sensitivity, vascular permeability and lipid profile in a rat model of type 2 diabetes mellitus

The impact of flaxseed (FSD) intake, a rich source of alpha linolenic acid (ALA), fiber and lignans, on the cardiovascular system is well documented. However, mechanisms by which flaxseed improve cardiovascular health are not clear. The aim of this study was to investigate the effects of dietary flaxseed on vascular permeability and endothelial function in streptozotocin-induced type 2 diabetes in rats. Type 2 diabetes mellitus (T2DM) was induced in male Sprague-Dawley rats by intraperitoneal injection of streptozotocin (35 mg/kg body weight) after short term feeding of high fructose diet. Diabetic rats were divided into three groups, one group fed standard diet, second group fed standard diet supplemented with defatted flaxseed powder (FSD), and third group received Metformin (200 mg/kg BW (body weight)) for 8 weeks. Fasting serum concentrations of glucose (FPG), insulin, vascular endothelial growth factor (VEGF), nitric oxide (NO), uric acid (UA) and lipid profile were measured. Vascular permeability index (VPI) was assessed at the end of experiment by quantifying the extravasation of albumin-bound Evans blue (EB) dye in the heart. Dietary FSD supplementation is comparable to Metformin in modulating blood lipid profiles, insulin and FPG levels. FSD intake was associated with significant reductions in serum insulin (-66%), glucose (-68%), VEGF levels (-66.8%) and UA (-63%), and NO (-37.5%) as compared to diabetic group without FSD supplementation. There were also improvements in lipid profile, vascular permeability index (VPI), insulin resistance and atherogenic indices in diabetic rats supplemented with flaxseed. These results suggest that dietary FSD supplementation may reduce the incidence of diabetic vascular complications through improvement of insulin sensitivity, vascular permeability and lipid profile. Key words:

In vitro cytotoxicity and induction of apoptosis by multiwalled carbon nanotubes in human peripheral lymphocytes: Correlation with physicochemical properties

Multiwalled carbon nanotubes (MWCNTs) consist of more than 80% of the current nanomaterials’ applications worldwide. Despite their wide application, little information is known concerning their impact on human health. The current study aims to identify the in vitro effects of exposure of the human peripheral blood lymphocytes (PBL) to MWCNTs and the possible associations with their physiochemical properties. Two doses (50 and 500 μg/ml) of four different commercially available MWCNTs (obtained from Frascati Laboratory, Sigma Co., Sun Nanotech Co. and Shenzhen Co.) were used in this study. Cell viability and apoptotic activity were evaluated by trypan blue exclusion test and Annexin-V/PI staining in peripheral blood leukocytes (PBL). Physicochemical properties of the different MWCNTs were determined and correlated with the cytotoxicity results after exposure for 12 and 48 h. Results indicate that PBL exposed to MWCNTs showed decreased cell viability and increased apoptosis in a dose- and time-dependent manner. The Pearson’s correlation test showed a lack of relationship between diameter of nanoparticles and their pro-apoptotic activity (r 2 = 0.282), whereas significant correlations were found between pro-apoptotic activity and the presence of some metal contaminants such as nickel, cobalt and gold (r 2 = 0.919, 0.698 and 0.520, respectively). Our results therefore suggest that carbon nanotubes at high concentrations lowered cell viability in vitro and induced apoptosis in human cells in vitro. In addition, the results indicate that metal contaminants in carbon nanotubes may be causative of some of the adverse outcomes observed. Finally, our finding provides important information on the biohazard potential of some carbon nanotubes in humans.

L-Asparaginase Isolated from Phaseolus vulgaris Seeds Exhibited Potent Anti-Acute Lymphoblastic Leukemia Effects In-Vitro and Low Immunogenic Properties In-Vivo

Escherichia coli-derived L-asparaginases have been used in the treatment of acute lymphoblastic leukemia (ALL), however, clinical hypersensitivity reactions and silent inactivation due to antibodies against E. coli-asparaginase, lead to inactivation of these preparations in most cases.Therefore, this study was aimed to investigate the cytotoxicity and antitumor effects ofa novel L-asparaginaseenzyme, isolated from Phaseolus vulgaris seeds (P-Asp) on the ALL cell line (Jurkat). The immunogenicity of the enzyme was also evaluated in-vivo and results were compared to commercially available enzymes of microbial sources. The data demonstrated that P-Asp has an enhanced anti-proliferative effect on ALL cells as detected by the WST-8 cell viability assay kit. Cells treated with P-Asp also exhibited a higher degree of early apoptosis compared with asparaginase from Escherichia coli (L-Asp) or its pegylated form Pegasparagas (PEG-ASP) that induced higher rates of late apoptosis and necrosis as detected by an Annexin V/Propidium iodide binding assay. In-vivo experiments indicated that mice treated with P-Asp had less distinct allergenic responses than other bacterial enzyme preparations as indicated by lower serum concentrations of IgG, IgE, IgM and mMCP-1 compared with other treated groups. In conclusion, P-Asp can be considered as a promising candidate for use in the treatment of ALL.

Purification and Characterization of Asparaginase from Phaseolus vulgaris Seeds.

L-asparaginase from bacteria has been used in treatment of acute lymphoblastic leukemia. The aim of this study was to purify and characterize L-asparaginase from Phaseolus vulgaris seeds instead of microbial sources. L-asparaginase was purified to apparent homogeneity. The enzyme has molecular mass of 79 kDa. The purified asparaginase had very low activity toward a number of asparagine and glutamine analogues. L-asparaginase was free from glutaminase activity. Kinetic parameters, Km and Vmax of purified enzyme, were found to be 6.72 mM and 0.16 μM, respectively. The enzyme had optimum pH at 8.0. The enzyme showed high stability at alkaline pH (pH 7.5–9.0) when incubated for up to 24 h. L-asparaginase had the same temperature optimum and thermal stability at 37°C. K+ was able to greatly enhance the activity of asparaginase by 150% compared with other metals tested. In conclusion, L-asparaginase showed no glutaminase activity and good stability over a wide range of physiological conditions, and thus it could be used as a potential candidate for treatment of acute lymphoblastic leukemia.