Gender-Specific Association Between FGFR4 Gly388Arg Gene Variants and Hypertension.

AIMS: Variations in fibroblast growth factor (FGF) levels have been associated with alterations in blood pressure. FGFs mediate their function through binding to their FGF receptor (FGFR). The FGFR4 Gly388Arg polymorphism is associated with cancer and cardiovascular diseases, but its association with hypertension is unclear. Here, we aimed to investigate the association between the FGFR4 Gly388Arg polymorphism and hypertension. MATERIALS AND METHODS: Three hundred Saudi individuals (150 normotensive controls and 150 hypertensive subjects) were genotyped for the FGFR4 Gly388Arg (G/A) polymorphism using polymerase chain reaction-restriction fragment length polymorphism method. Anthropometrics, glucose and lipid profiles were measured for all subjects. The frequency of the FGFR4 Arg388 (A) allele was significantly higher in hypertensive subjects (36%) than controls (24.3%) (odds ratio [OR] 2.4, 95% confidence interval [CI] 1.5-3.83, p < 0.001). In addition, GA (OR 2.51, 95% CI 1.3-4.85, p = 0.006), AA (OR 5.58, 95% CI 1.79-11.8, p = 0.003), and GA + AA (OR 2.91, 95% CI 1.55-5.46, p = 0.001) genotypes were significantly associated with the risk of hypertension, even after adjusting for age, body mass index, and glucose. Gender stratification showed a significant association only in female subjects (p < 0.001). Furthermore, subjects with GA and AA genotypes showed significantly higher diastolic blood pressure than those with GG genotype (p = 0.004). CONCLUSION: The FGFR4 Arg388 allele is associated with an increased risk of hypertension in Saudi female subjects. The lack of association in men needs to be further investigated.

Lithocholic acid induces endoplasmic reticulum stress, autophagy and mitochondrial dysfunction in human prostate cancer cells.

Lithocholic acid (LCA) is a secondary bile acid that is selectively toxic to human neuroblastoma, breast and prostate cancer cells, whilst sparing normal cells. We previously reported that LCA inhibited cell viability and proliferation and induced apoptosis and necrosis of androgen-dependent LNCaP and androgen-independent PC-3 human prostate cancer cells. In the present study, we investigated the roles of endoplasmic reticulum (ER) stress, autophagy and mitochondrial dysfunction in the toxicity of LCA in PC-3 and autophagy deficient, androgen-independent DU-145 cells. LCA induced ER stress-related proteins, such as CCAAT-enhancer-binding protein homologous protein (CHOP), and the phosphorylation of eukaryotic initiation factor 2-alpha (p-eIF2α) and c-Jun N-terminal kinases (p-JNK) in both cancer cell-types. The p53 upregulated modulator of apoptosis (PUMA) and B cell lymphoma-like protein 11 (BIM) levels were decreased at overtly toxic LCA concentrations, although PUMA levels increased at lower LCA concentrations in both cell lines. LCA induced autophagy-related conversion of microtubule-associated proteins 1A/1B light chain 3B (LC3BI-LC3BII), and autophagy-related protein ATG5 in PC-3 cells, but not in autophagy-deficient DU-145 cells. LCA (>10 µM) increased levels of reactive oxygen species (ROS) concentration-dependently in PC-3 cells, whereas ROS levels were not affected in DU-145 cells. Salubrinal, an inhibitor of eIF2α dephosphorylation and ER stress, reduced LCA-induced CHOP levels slightly in PC-3, but not DU-145 cells. Salubrinal pre-treatment increased the cytotoxicity of LCA in PC-3 and DU-145 cells and resulted in a statistically significant loss of cell viability at normally non-toxic concentrations of LCA. The late-stage autophagy inhibitor bafilomycin A1 exacerbated LCA toxicity at subtoxic LCA concentrations in PC-3 cells. The antioxidant α-tocotrienol strongly inhibited the toxicity of LCA in PC-3 cells, but not in DU-145 cells. Collectively, although LCA induces autophagy and ER stress in PC-3 cells, these processes appear to be initially of protective nature and subsequently consequential to, but not critical for the ROS-mediated mitochondrial dysfunction and cytotoxicity of LCA. The full mechanism of LCA-induced mitochondrial dysfunction and cytotoxicity in the similarly sensitive DU-145 cells remains to be elucidated.

Exposure to difenoconazole, diclofop-methyl alone and combination alters oxidative stress and biochemical parameters in albino rats.

The herbicides diclofop-methyl and the fungicide difenoconazole are widely used in agriculture and may lead to serious toxicity risks. However, limited studies have been done to evaluate differences in the metabolic effects of these herbicides. Difenoconazole (10 mg/kg) and Diclofop-methyl (1 mg/kg) were orally administrated individually (Groups 1 and 2 respectively) as well as combined (G3) to rats for 28 days. In all treated groups, alanine aminotransferase (ALT) and urea were significantly higher than the control group. Plasma creatinine was also significantly higher in groups G1 and G2 than control. Significant inhibition in gamma glutamyltransferase (γGT) was observed in all treated groups, in addition to significant inhibition of plasma acetylcholinesterase enzyme (AChE) in G3 (p < 0.01). There was no effect in aspartate aminotransferase (AST) and albumin. Total plasma triiodothy-ronine (T3) hormone was significantly higher in groups G2 and G3 (p < 0.01), but significantly lower in G1 group as compared to control. Thyroxin (T4) was significantly lower in all treated groups than control. Cholesterol level was significantly lower in G3 than control, and a total protein (TP) was significantly higher in all treated groups than control. No differences were observed in glucose levels. Malondialdehyde (MDA) and superoxide dismutase (SOD), an oxidative stress biomarker, was significantly increased in all treated groups comparing to control. Sulphur containing protein (SH-protein) was significantly lower in G1 than control. No significant changes were observed for GST in all treatments. The significant differences in measured biomarkers after application of diclofop-methyl, difenoconazole individually and combined indicate that the investigated pesticides may have potentially harmful effects on humans and the surrounding environment. We suggest that larger studies be conducted to better understand the toxicity mechanisms of these pesticides.

Th1/Th2 cytokine pattern in Arab children with severe asthma.

BACKGROUND: Bronchial Asthma has recently emerged as one of the most prevalent diseases in Arab countries. Environmental and geographical influences were shown to be the reasons of the variations in the rates of prevalence; no analyses have nevertheless yet been performed on the immunologic background associated with this condition in Arabic children. OBJECTIVES: To examine the cytokine production from T cells in children with and without asthma, and to determine the role of the most related cytokine patterns in childhood asthma. METHODS: A total of 195 Saudis children (98 asthma pediatric patients and 97 healthy controls) were randomly selected from the Riyadh Cohort Study for inclusion. Asthma was based on established pediatric diagnosis and medications taken. RESULTS: Significant differences were observed between the two groups, thus, GMCSF, INF-γ, IL-5, IL-6, IL-8 and IgG-3 were reduced in patients compared to controls; in these same patients IgE, resistin, IL-4 and IgG-4 were significantly increased. In contrast with these results no differences between patients and controls were seen in CRP, TNF-α, IL-1, IL-2, IL-7, IL-10, IL-13, IgG-1, IgG-2, IgG-A and IgG-M. Result of a principal component analysis suggested that IL4. INF-γ and IgE are major players in the pathogenesis of asthma in Arabic children. CONCLUSION: These are the first data obtained in asthmatic children in Saudi; data herein confirm that this disease is associated with a profound degree of immune impairment independently of the peculiar genetic of the analyzed individuals, and of the environmental conditions that are present in this part of the world.

Vitamin D receptor gene polymorphisms are associated with obesity and inflammosome activity.

To explore the mechanisms underlying the suggested role of the vitamin D/vitamin D receptor (VDR) complex in the pathogenesis of obesity we performed genetic and immunologic analyses in obese and non-obese Saudi individuals without other concomitant chronic diseases. Genomic DNA was genotyped for gene single nucleotide polymorphisms (SNPs) of VDR by allelic discrimination in 402 obese (body mass index -BMI≥30 kg/m2) and 489 non-obese (BMI<30 kg/m2) Saudis. Q-PCR analyses were performed using an ABI Prism 7000 Sequence Detection System. The inflammosome pathway was analysed by PCR, cytokines and plasma lipopolysaccaride (LPS) concentrations with ELISA assays. Results showed that the VDR SNPs rs731236 (G) (TaqI) and rs1544410 (T) (Bsm-I) minor allele polymorphisms are significantly more frequent in obese individuals (p = 0.009, ß = 0.086 and p = 0.028, ß = 0.072, respectively). VDR haplotypes identified are positively (GTA) (p = 0.008, ß = 1.560); or negatively (ACC) (p = 0.044, ß = 0.766) associated with obesity and higher BMI scores. The GTA "risk" haplotype was characterized by an up-regulation of inflammosome components, a higher production of proinflammatory cytokines (p<0.05) and a lower VDR expression. Plasma LPS concentration was also increased in GTA obese individuals (p<0.05), suggesting an alteration of gut permeability leading to microbial translocation. Data herein indicate that polymorphisms affecting the vitamin D/VDR axis play a role in obesity that is associated with an ongoing degree of inflammation, possibly resulting from alterations of gut permeability and microbial translocation. These results could help the definition of VDR fingerprints that predict an increased risk of developing obesity and might contribute to the identification of novel therapeutic strategies for this metabolic condition.

Polycyclic aromatic hydrocarbon distribution in serum of Saudi children using HPLC-FLD: marker elevations in children with asthma.

Diesel exhaust consists of a complex mixture of chemicals which contain known genotoxicants, one of which is polycyclic aromatic hydrocarbons (PAHs) which may be associated with adverse respiratory health outcomes. This study aimed to evaluate the distribution patterns of PAHs (anthracene, naphthalene, fluorene, phenanthrene, cyclopentaphenanthrene, pyrene, fluoranthene, benzanthracene, chrysene, benzo(e)pyrene, benzoacephenanthrylene, and benzo(a)pyrene) in serum collected from asthmatic and healthy control children. PAH serum levels were measured in samples collected from children who lived in 11 different locations in/round Riyadh, Saudi Arabia (Al-yarmouk, Usaibi, Sultana Al-kadema, Omrrojam, Kof, Janoob Dawdmi, Guberah, Arabbuah, Al-mozahemyah, Iskan Al-mazzer, and Al-gharabi) during the period 2010-2011. Our results showed that the highest total mean concentrations of PAH were found in serum samples collected from people who lived in Sultana Aljadhida, Almozahemyah, Guberah, and Omrrojam and were 663.9, 486.17, 412.18, and 258.6 ng ml(-1), respectively. The most prevalent PAHs in serum samples were naphthalene, bezanthracene, benzoacephenanthrylene, phenanthrene, chrysene, and benzo(a)pyrene with a frequency that ranged from 54.5 to 90.9 % positive samples. A close monitoring of PAH pollution is strongly recommended, especially in food and plant samples, because of their high bioaccumulation capacity.

Metabolic syndrome biomarkers and early breast cancer in Saudi women: evidence for the presence of a systemic stress response and/or a pre-existing metabolic syndrome-related neoplasia risk?

BACKGROUND: Obesity has been linked to many adverse health consequences, including breast cancer. This study aims to determine adipocytokine and other biological changes in recently diagnosed breast cancer patients before therapy is started. METHODS: A total of 109 female Saudi subjects [56 newly diagnosed, treatment-naïve, histologically-confirmed breast cancer cases and 53 age- and BMI-matched controls] were enrolled in this study. Anthropometric data were collected. Serum insulin, adipocytokines and plasminogen activator inhibitor-1 (PAI-1) concentrations were measured using a customized multiplex Luminex assay. Hypersensitive C-Reactive Protein (CRP), tumor necrosis factor-alpha (TNF-α), and angiotensin II (ANG II) were measured using ELISA. RESULTS: A few days in the diagnosis, breast cancer subjects had significantly higher systolic blood pressure (p = 0.03), glucose (p = 0.01), triglycerides (p = 0.001), leptin (p = 0.044), resistin (p = 0.04), ANG II (p = 0.02), TNF-α (p = 0.045), and CRP (p = 0.04) than the controls. On the other hand, HDL (p = 0.01) and adiponectin (p = 0.02) were significantly lower in cancer subjects than controls. A significant association was found between elevated triglycerides (TG) and breast cancer [OR (95% CI), 6.1(1.8, 15.6), p = 0.004], as well as elevated ANG II [OR (95% CI), 5.2(1.2, 14.3), p = 0.03]. On the other hand, aPAI and HDL correlated negatively with breast cancer [OR (95% CI), 0.076(0.01, 0.34), p = 0.001; 0.30(0.09, 0.95), p 0.04, respectively]. CONCLUSION: Circulating ANGII and triglycerides were positively associated with early breast cancer. In contrast, HDL-cholesterol correlated negatively with ANG II and aPAI in these patients. This suggests that patients with recently diagnosed breast cancer have biochemical changes consistent with an activated stress response and/or that patients with metabolic syndrome manifestations have a higher risk of developing this disease.

Polycyclic aromatic hydrocarbon exposure and pediatric asthma in children: a case-control study.

BACKGROUND: Bronchial asthma is one of the most prevalent diseases in Arab children. Environmental pollution has been suggested to be considered causative of asthma, nasal symptoms and bronchitis in both children and adult. The objectives of this study were to evaluate the association between serum polycyclic aromatic hydrocarbons (PAHs) levels, asthma and allergic outcomes among Saudi children aged up to 15 yrs. We hypothesized that increased serum PAHs are associated with allergy, asthma, or respiratory symptoms. METHODS: A total of 195 Saudi children (98 asthma pediatric patients and 97 healthy controls) were randomly selected from the Riyadh Cohort Study for inclusion. The diagnosis of Asthma was based on established pediatric diagnosis and medications taken. RESULTS: Asthma related markers showed highly significant differences between children with and without asthma. Thus IgE, resistin and IL-4 were significantly increased (p 0.004, 0.001 and 0.003, respectively) in children with asthma compared with non-asthma control subjects. GMCSF, IFN-γ, IL-5, IL-8 and IL-10, on the other hand, were significantly decreased in children with asthma (p 0.003, 0.03, 0.001, 0.004 and 0.03, respectively). Strong associations between serum PAHs levels and biomarkers of childhood asthma were detected in Arabic children. Data confirmed the role of naphthalene, 4H-cyclobenta[def]phenanthrene, 1,2-benzanthracene, chrysene and benzo(e)acephenanthrylene in childhood asthma; levels of these PAHs were correlated with asthma related biomarkers including IgE, resistin, GMCSF and IFN-γ as well as IL-4, IL-5, IL-8 and IL-10 cytokines. CONCLUSIONS: This data highlight the pivotal role of specific PAHs in childhood asthma.

Increased circulating ANG II and TNF-α represents important risk factors in obese saudi adults with hypertension irrespective of diabetic status and BMI.

Central adiposity is a significant determinant of obesity-related hypertension risk, which may arise due to the pathogenic inflammatory nature of the abdominal fat depot. However, the influence of pro-inflammatory adipokines on blood pressure in the obese hypertensive phenotype has not been well established in Saudi subjects. As such, our study investigated whether inflammatory factors may represent useful biomarkers to delineate hypertension risk in a Saudi cohort with and without hypertension and/or diabetes mellitus type 2 (DMT2). Subjects were subdivided into four groups: healthy lean controls (age: 47.9±5.1 yr; BMI: 22.9±2.1 Kg/m(2)), non-hypertensive obese (age: 46.1±5.0 yr; BMI: 33.7±4.2 Kg/m(2)), hypertensive obese (age: 48.6±6.1 yr; BMI: 36.5±7.7 Kg/m(2)) and hypertensive obese with DMT2 (age: 50.8±6.0 yr; BMI: 35.3±6.7 Kg/m(2)). Anthropometric data were collected from all subjects and fasting blood samples were utilized for biochemical analysis. Serum angiotensin II (ANG II) levels were elevated in hypertensive obese (p<0.05) and hypertensive obese with DMT2 (p<0.001) compared with normotensive controls. Systolic blood pressure was positively associated with BMI (p<0.001), glucose (p<0.001), insulin (p<0.05), HOMA-IR (p<0.001), leptin (p<0.01), TNF-α (p<0.001) and ANG II (p<0.05). Associations between ANG II and TNF-α with systolic blood pressure remained significant after controlling for BMI. Additionally CRP (p<0.05), leptin (p<0.001) and leptin/adiponectin ratio (p<0.001) were also significantly associated with the hypertension phenotype. In conclusion our data suggests that circulating pro-inflammatory adipokines, particularly ANG II and, TNF-α, represent important factors associated with a hypertension phenotype and may directly contribute to predicting and exacerbating hypertension risk.

Soluble CD163 is associated with body mass index and blood pressure in hypertensive obese Saudi patients.

BACKGROUND: The hallmark of vascular inflammation is the recruitment of circulating leucocytes, primarily monocytes, macrophages and T lymphocytes, into the vascular wall; however, the link between monocyte/macrophage activation and hypertension has not been established as yet. In this study, we determined how sCD163, a monocyte/macrophage soluble scavenger receptor and immunomodulator, relates to arterial blood pressure (BP) in hypertensive Saudi individuals. MATERIALS AND METHODS: A total of 90 (30 non-hypertensive obese, 30 hypertensive obese and 30 lean normotensive controls) adult Saudi subjects, aged 40-60 years, participated in this cross-sectional study. Serum fasting blood glucose, triglycerides, total cholesterol, HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), leptin, adiponectin, resistin, insulin, tumour necrosis factor-alpha (TNF-α), PAI-1, angiotensin II, high-sensitivity C-reactive protein (hsCRP) and sCD163 were measured in all subjects studied. RESULTS: sCD163 concentrations were significantly increased in obese hypertensive patients compared to controls (P=0.016). Positive correlations between sCD163 and body mass index (BMI) (r=0.27, P=0.01), systolic BP (r=0.25, P=0.01), diastolic BP (r=0.33, P=0.001), LDL-C (r=0.21, P=0.04), TNF-α (r=0.23, P=0.02) and hsCRP (r=0.33, P=0.008) were observed. Positive correlations between sCD163 and diastolic BP (r=0.23, P=0.04) and LDL-C (r=0.22, P=0.03) remained significant after controlling for BMI. CONCLUSIONS: Taken together, these data demonstrate that the monocyte/macrophage activation-related sCD163 is positively associated with BMI and increased arterial BP with the elevation in diastolic BP being independent of the BMI.

Plasma neuropeptide Y levels relate cigarette smoking and smoking cessation to body weight regulation.

Loss and disproportionate gain of body weight often seen respectively in smokers and quitters are believed to be due to disrupted energy homeostasis induced by nicotine, the major constituent of cigarette smoke. Energy homeostasis is suggested to be regulated by the coordinated actions of peripheral adipose tissue derived leptin and the brain hypothalamic orexigenic neuropeptide Y (NPY). While the studies probing the role of leptin and NPY in weight modulating effect of nicotine have so far been inconsistent and based largely on animal systems, there is a paucity of data involving human subjects. Here we measured the plasma levels of orexigenic neuropeptide Y (NPY) and leptin in 35 non-smokers and 31 cigarette smokers before and three months after smoking cessation. Compared to non-smokers, smokers were leaner and had reduced NPY and leptin levels. Smoking cessation resulted in a significant weight gain and increased waist circumference accompanied by increased leptin and NPY levels. NPY levels were significantly correlated with body weight (r=0.43, p<0.05), BMI (r=0.41, p<0.05), and waist circumference (r=0.37, p<0.05), while leptin correlated with BMI (r=0.42, p<0.05) and waist circumference (r=0.39, p<0.05). Association of leptin with smoking status, but not that of NPY, was lost after controlling for anthropometric parameters. Weight modulating effect of cigarette smoke may thus involve its direct action on NPY, independent of leptin. Altered leptin levels in smokers and quitters may merely reflect changes in body weight or precisely fat mass.

Variants of endothelial nitric oxide synthase gene are associated with components of metabolic syndrome in an Arab population.

Genetics plays a crucial role in the development of metabolic syndrome (MetS). Here we examined the association between endothelial nitric oxide synthase (eNOS) gene polymorphisms and MetS in a Saudi Arabian cohort to extend the understanding of the genetic basis of MetS in diverse ethnic populations. Anthropometric, clinical and biochemical parameters as well as genotyping for 894G>T, -786T>C variants of eNOS gene by PCR-RFLP and 4a/b by direct PCR were performed in 886 Saudi Arabians (477 MetS and 409 Non-MetS). The genotype distribution (TT, p=0.001; TC, p=0.001; TC+CC, p=0.001) and allele (T, p=0.007; C, p=0.007) frequency of the -786T>C SNP were significantly different between Non-MetS and MetS subjects which remained significant after Bonferroni correction. Moreover: 1) the GT and GT+TT genotypes of the 894G>T SNP were associated with elevated blood pressure (p=0.017, and p=0.022, respectively); 2) the ab variant of 4a/b polymorphism was associated with decreased HDL levels (p= 0.044); and 3) the TC+CC genotype and C allele of the -786T>C SNP were associated with increased fasting glucose levels (p=0.039, and p=0.028, respectively). Also, G-a-C was identified as the risk haplotype for MetS susceptibility (p=0.034). The results suggest a significant association of 894G>T, 4a/b and -786T>C polymorphisms with MetS and its components is present in an Arab population. A genetic predisposition to develop abnormal metabolic phenotypes, consistent with an increased prevalence of metabolic phenotypes can be detected in this ethnic group.

Vitamin D receptor gene polymorphisms and HLA DRB1*04 cosegregation in Saudi type 2 diabetes patients.

The vitamin D receptor (VDR) gene has been involved in the modulation of susceptibility to inflammatory and autoimmune conditions, and could play a role in the pathogenesis of type 2 diabetes mellitus (T2DM). Susceptibility to T2DM was recently also suggested to associate with HLA alleles. We evaluated possible correlations between VDR polymorphisms, HLA alleles, and risk for development of T2DM by analyzing 627 individuals (368 T2DM patients and 259 healthy control subjects) part of a well-characterized cohort followed in Riyadh, Kingdom of Saudi Arabia. Genomic DNA was genotyped for the VDR gene single nucleotide polymorphisms of Fok-1, Taq-1, ApaI, and Bsm-I. Analyses were run by allelic discrimination real-time PCR. HLA genotyping was performed as well by PCR using sequence-specific primers, whereas cytokine production was evaluated by FACS. Results showed T2DM to be significantly associated with the VDR Taq1 (rs731236-AG) and Bsm-I (rs1544410-CT) genotypes, and the VDR rs1544410-T allele. Cosegregations resulting in significant increases of T2DM odds ratio were detected between Taq1 and Bsm-I VDR polymorphisms and HLA DRB1*04. Notably, the VDR polymorphisms observed to be more frequent in T2DM patients correlated with increased VDR expression and IL-12 production, as well as with metabolic parameters of susceptibility to T2DM, including serum cholesterol and high-density lipoprotein levels. VDR polymorphisms are present in T2DM, and correlate with HLA DRB1*04 and with immunologic and metabolic parameters; results from this study add T2DM to the list of diseases that are likely modulated by an HLA/VDR interaction.

Long-term exposure to incense smoke alters metabolism in Wistar albino rats.

The burning of incense is an important source of indoor air pollution in Asia. We assessed the effect of long-term exposure to incense smoke on the body weight and levels of circulating glucose, triglycerides, total cholesterol, HDL-cholesterol, insulin, adiponectin and leptin in Wistar albino rats. Two groups of rats were used. First group (n = 12) was exposed daily to incense smoke for 4 months at the rate of 4 g day(-1) in the exposure chamber. Another group of rats (n = 12), was used as non-exposed control. Blood samples were collected from all animals after 4, 8, 12 and 16 weeks of exposure. Serum glucose, triglycerides, total cholesterol and HDL-cholesterol, LDL-cholesterol insulin, adiponectin and leptin were measured. Our results showed that incense smoke exposure was associated with decreased weight gain and the adverse metabolic changes of increased triglycerides and decreased HDL-cholesterol concentrations. Exposure to incense was also associated with a transient increase of leptin levels. Taken together, these data suggest that incense smoke influences metabolism adversely in rats. The effect of incense smoke on human health and the underlying mechanisms need to be studied further.

Endothelial nitric oxide synthase gene polymorphisms (894G > T and -786T > C) and risk of coronary artery disease in a Saudi population.

BACKGROUND AND AIMS: Endothelial nitric oxide synthase gene polymorphisms, either independently or through gene environmental interactions, are associated with cardiovascular diseases in multiple ethnic populations. However, no information is available with regard to such associations in a Saudi population despite a high incidence of cardiovascular abnormalities. We studied the associations of 894G>T and -786T>C polymorphisms of endothelial nitric oxide synthase gene with coronary artery disease in Saudi population. METHODS: Variants 894G>T and -786T>C were studied in 142 coronary artery disease patients and 145 normal controls by PCR-restriction fragment length polymorphism analysis and allele specific PCR, respectively. RESULTS: Carriers of GT and TT genotypes of 894G>T polymorphism were significantly high (p <0.0001) in patients (47.2 and 7%, respectively) than in controls (27.6 and 4.8%, respectively). Likewise, carriers for TC and CC genotypes of -786T>C polymorphism were significantly high (p <0.001) in patients (50 and 32% respectively) than in controls (34.5 and 22.5% respectively). Both 894G>T [OR (95% CI); 4.39 (1.69-11.42)] and -786T>C [OR (95% CI); 2.74 (1.02-7.32]) variants were independently associated with the disease status. Genotype distributions of 894G>T and -786T>C polymorphisms in the diseased and control populations matched with those found in Caucasian populations. CONCLUSION: This study, for the first time, suggests an independent association of 894G>T and -786T>C polymorphisms of endothelial nitric oxide synthase gene with coronary artery disease in a Saudi population.

Effects of PEG-interferon-alpha-2A on Schistosoma mansoni infection in mice.

In some regions of the world, co-existence of schistosomiasis and hepatitis C (HCV) infection is common. Because the morbidity in human schistosomiasis is primarily due to host cell-mediated immune response, it was of interest to determine the effects on Schistosoma mansoni infection of an immune stimulator used in the standard treatment of HCV infection. Schistosoma mansoni -infected mice were treated with PEG-interferon-alpha-2a (PEG-IFN-alpha) by subcutaneous injection. Groups 1, 2, and 3 received 0.2 microg, 0.6 microg, and 1 microg PEG-IFN-alpha/wk, respectively, while group 4 received saline. The total worm burden was lower in all treated groups, with a maximal reduction of 35% after 9 wk of treatment with 1 microg PEG-IFN-alpha. Interferon treatment also increased the proportion of single worms over pairs. Ova counts in intestine and liver, as well as the number of liver granulomas, were greatly decreased at all time points for all treated groups. PEG-IFN-alpha also had inhibitory effects on the size of granulomas after 4 wk of treatment. The results suggest that PEG-IFN-alpha may be worth investigating for the treatment of human schistosomiasis when standard oral agents cannot be used, or when rapid inhibition of granuloma formation may be a priority.

Relationship between resistin and aPAI-1 levels with insulin resistance in Saudi children.

BACKGROUND: Association of resistin with insulin resistance (IR) in humans is still controversial and few studies have investigated the association of plasminogen activator inhibitor-1 (PAI-1) with IR in children. The purpose of the present study was therefore to evaluate serum levels of resistin and active PAI-1 (aPAI-1) in Saudi children and their association with the various obesity-related complications. METHODS: In this cross-sectional study, 73 boys and 77 girls with varying body mass index (BMI) were recruited. They were assessed for anthropometric measures and fasting serum levels of glucose, insulin, lipid profile, resistin, angiotensin II (ANG II) and aPAI-1. RESULTS: Resistin was positively correlated with hips (r = 0.33, P < 0.01), waist (r = 0.23, P < 0.05) and BMI (r = 0.33, P < 0.01). The association of resistin with the markers of obesity was also significant in girls but lost significance in boys. aPAI-1 was positively correlated with total cholesterol (r = 0.24; P < 0.01), triglycerides (r = 0.2, P < 0.05), HOMA-IR (r = 0.26, P < 0.01) and insulin (r = 0.26, P < 0.01). The significant association of aPAI-1 with IR was also true in girls but lost significance in boys. CONCLUSION: Resistin is not correlated with IR and further studies are needed to explore the role of resistin especially in childhood obesity. In contrast, increased levels of PAI-1 may contribute to the risk of cardiovascular diseases related to obesity and insulin resistance in children. The observed gender-related differences in the association between resistin, aPAI-1 with obesity markers and IR could be attributed to sexual dimorphism in body fat distribution.

Retinol binding protein-4 is associated with TNF-alpha and not insulin resistance in subjects with type 2 diabetes mellitus and coronary heart disease.

We studied the association between RBP4 and various markers related to insulin resistance and diabetic complications as well as inflammatory markers in Saudi population suffering from type 2 diabetes and coronary heart disease. Patients with type 2 diabetes were divided into 3 groups according to the type of treatment and involvement of coronary artery disease. Serum RBP4, TNF-alpha, insulin, CRP, resistin, leptin and adiponectin were analysed in all samples. RBP4 levels increased significantly in the group of diabetic subjects treated with oral hypoglycemic agents and diabetic patients with coronary heart disease (30.2 +/- 11.8; 33.4 +/- 13.6 respectively), while there was no significant change in the other group for diabetic subjects on low-carbohydrate diet (25.1 +/- 10.9) compared to control group (22.6 +/- 9.5). RPB4 levels were positively correlated with TNF-alpha in the group of diabetic subjects on oral hypoglycemic agents and diabetic patients with coronary heart disease (r = 0.52, P < 0.05; r = 0.58, P < 0.05 respectively). No correlations were found between RBP4 levels and insulin resistance in all studied groups. Our findings suggest that serum RBP4 levels is associated with pro-inflammatory cytokine (TNF-alpha) and is not associated with insulin resistance among patients with type 2 diabetes and coronary heart disease.

Host susceptibility to schistosomes: effect of host sera on cell proliferation of Schistosoma mansoni schistosomula.

To determine effects of the sera on cell proliferation, schistosomula of Schistosoma mansoni (20-days-old) were incubated in medium containing fetal calf serum plus hamster (highly susceptible host) portal or peripheral venous serum, or rat (poorly susceptible host) portal or peripheral venous serum in the presence of bromodeoxyuridine (BrdU). Compared with schistosomula cultured in presence of control medium containing fetal calf serum alone, BrdU labeling indices (BLIs) were increased by 39% in the presence of portal, but not in peripheral, serum of hamsters. In contrast, no significant differences were observed in the BLIs in rat portal, or peripheral, sera or in control media. In vivo BrdU labeling results revealed that there was no detectable cell proliferation in S. mansoni schistosomula (6 days old) in the lungs. However, cell proliferation was detected in schistosomula beginning at 17 days. The results indicated that portal venous serum from a highly susceptible host, but not from a poorly susceptible host, stimulated schistosome cell proliferation in vitro. The timing of the increase in cell proliferation in terms of development corresponded to liver portal-mesenteric localization of schistosomula. Together, the data support the conclusion that in susceptible hosts, portal serum may play a role in schistosome cell proliferation, possibly resulting in termination of schistosome migration. This may explain the colocalization of adults, and the known organ selectivity of disease.