Low Plasma 25-Hydoxyvitamin D at Diagnosis Predicts Poor Outcomes in Patients with Bladder Cancer: A Prospective Cohort Study.

This study aimed to investigate whether plasma 25-hydroxyvitamin D (25-OHD) at diagnosis predicts poor outcomes in patients with urothelial bladder cancer. A total of 177 patients with non-muscle-invasive bladder cancer (NMIBC) were prospectively followed up over a period extending beyond 6 years. Data on poor outcomes (ie., recurrence, progression, and mortality) were collected. Plasma 25-OHD was measured by immunoassay. Cutoff-Finder web application was used to determine the best 25-OHD cutoff point to predict a specific poor outcome. Cox-hazard models were applied to test how plasma 25-OHD affect patients outcome while adjusting for potential confounding factors. During the follow-up period, tumor recurrence and progression occurred in 40.7% and 14.1% of patients, respectively and 11.3% of patients died. Baseline 25-OHD was lower in patients who experienced poor outcome (12.2 ± 7.44 vs. 16.7 ± 10.6 ng/mL; p < 0.001). Multi-adjusted HR (95% CI) for vitamin D deficiency (25-OHD < 12 ng/mL) was 2.09 (1.27-3.44) for recurrence, 2.63 (1.06-6.49) for progression and 2.93 (1.04-8.25) for mortality in patients with NMIBC. Low plasma 25-OHD in NMIBC patients is associated with higher risk of poor outcome. Future work is required to test whether correction of vitamin D deficiency will improve quality of life and extend survival in these patients.

Interaction Effects of Plasma Vitamins A, E, D, B9, and B12 and Tobacco Exposure in Urothelial Bladder Cancer: A Multifactor Dimensionality Reduction Analysis.

The study aimed to examine circulating vitamins A, E, D, and B12 and folate in patients with urothelial bladder cancer (UBC) and detect potential interaction effects of these micronutrients on UBC risk. A case-control study was conducted on 262 UBC patients and 254 matched controls. Vitamins A and E were assessed by ultra performance liquid chromatography, and vitamins D and B12 and folate were assessed by immunological methods. Binary logistic regression models were used to test associations of plasma vitamins tertiles with UBC risk. A multifactor dimensionality reduction method (MDR) was applied to assess interactive effects of the vitamins and tobacco on UBC risk. Higher levels in vitamins A, E, and D were associated with lower occurrence of UBC. No significant association was observed in plasma folate or vitamin B12 with UBC. There were redundancy interactions of plasma vitamin D with tobacco and with plasma vitamin A on UBC risk. Even though the study could not ascertain causality, the findings suggest that vitamins A, E, and D might be protective against UBC. Vitamins A and D interact antagonistically with each other's and with tobacco to modulate UBC risk. These interactions should be taken in consideration for the prevention of UBC.

Associations of rs1883832 and rs4810485 polymorphisms of CD40 gene with myocardial infarction in the Tunisian population.

Context: Cluster of differentiation 40 (CD40), and its ligand CD40L, are major co-stimulatory molecules whose interactions are important in both cellular and humoral immunity, and has been suggested to play a role in the pathogenesis of acute coronary syndrome. Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1 C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians. Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1 C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p = 0.012 and p < 0.001, respectively). Conclusions: Our work showed a significant association between the -1 C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians.

Association of MTHFR C677T, MTHFR A1298C, and MTRR A66G Polymorphisms with Neural Tube Defects in Tunisian Parents.

OBJECTIVE: This study aims to investigate the association of 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and methionine synthase reductase (MTRR A66G) gene polymorphisms with neural tube defects (NTDs) in a Tunisian population. METHODS: Genotyping was performed by polymerase chain reaction with restriction fragment length polymorphisms (PCR-RFLPs) using the restriction enzymes. Allele and genotype frequencies were compared between mothers and fathers of fetuses with NTDs with matched controls based on an association analysis using SPSS software. RESULTS: MTHFR (C677T, A1298C) and MTRR A66G polymorphisms were found to be protector factors for NTD fetuses in the mother group. In addition, a combination of the three wild-type alleles C677/A1298/A66 has increased four-fold the incidence of NTDs (p = 0.004, OR = 3.96, 95% CI: 1.53-10.23). In the father group, MTHFR C677T was a risk factor for NTDs. However, no association was found between MTHFR A1298C, MTRR A66G, and the occurrence of this anomaly. The analysis of MTHFR C677T and MTRR A66G polymorphisms has demonstrated a significant difference in vitamin B12 levels between recessive and dominant genotypes in case mothers (p < 0.05). CONCLUSION: Additional studies are required to better understand the roles of parental gene polymorphisms related to folate-homocysteine metabolism in the pathogenesis of NTD.

Decreased Oleic Acid and Marine n - 3 Polyunsaturated Fatty Acids in Tunisian Patients with Urothelial Bladder Cancer.

Fatty acids (FAs) are thought to impact carcinogenesis by affecting cell signaling. A case-control study including 250 patients with urothelial bladder cancer (UBC) and 250 controls was conducted. Plasma FAs composition was assessed using capillary gas chromatography. Associations of individual and classes of FAs with UBC were controlled for the main risk factors for UBC. Plasma FAs profile was different in patients compared to controls. Higher levels (third tertile vs. first tertile) in palmitic acid (PA) [multi-adjusted OR (95% CI), 1.83 (1.14-2.92)], and n - 6:n - 3 FA ratio [4.13 (2.38-7.16)] were associated with increased risk for UBC [multi-adjusted OR (95% CI), 1.83 (1.14-2.92)]. In contrast, higher levels (third tertile vs. first tertile) in oleic [0.54 (0.34-0.86)], dihomo-γ-linolenic (DGLA) [0.47 (0.29-0.74)], eicosapentaenoic (EPA) [0.32 (0.19-0.52)], and docosahexaenoic (DHA) acids [0.33 (0.20-0.53)] were associated with lower risk for UBC. Although the study design does not allow proving causality, the findings suggest a possible protective role of oleic acid and marine n - 3 polyunsaturated FAs (PUFAs) against bladder carcinogenesis.

The rs9939609 polymorphism in the fat mass and obesity associated (FTO) gene is associated with obesity in Tunisian population.

CONTEXT: Variations in the fat mass and obesity-associated gene (FTO) has been associated with obesity in many populations, but the results are conflicting. OBJECTIVE: The aim of this study was to evaluate the effect of the rs9939609 polymorphism in the FTO gene on obesity risk and plasma leptin, adiponectin, insulin and lipid concentrations in Tunisians. MATERIALS AND METHODS: Four hundred and ninety-four subjects with obesity and 334 non-obese participated in this study. The rs9939609 (T/A) genotype was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: Significant differences in genotype frequencies were observed between cases and controls. In the separate analysis by gender, the association between the AA genotype and obesity was statistically significant in women but not in men. After stratification by obesity class this association remains only with obesity class III. DISCUSSION: Our study is in agreement with studies on Caucasian, Portuguese and Cebu Filipino populations where a gender-specific association was found between rs9939609 polymorphism and obesity. It is also in agreement with studies on Mexican, Spanish and European populations, where an association was found with obesity class III. CONCLUSION: The rs9939609 polymorphism of FTO gene is associated with obesity, especially obesity class III in women.

Haplotype-based association of Vascular Endothelial Growth Factor gene polymorphisms with urothelial bladder cancer risk in Tunisian population.

BACKGROUND/AIM: Accumulated data suggested that Vascular Endothelial Growth Factor is a major mediator in vasculogenesis, angiogenesis and recently in tumorigenesis. Therefore, we aimed to investigate for the first time the association between VEGF gene variants (-2549I/D (rs35569394), -2578C/A (rs699947), and +936C/T (rs3025039)) with urothelial bladder cancer (UBC) in Tunisian population. METHODS: A total of 218 UBC patients and 204 controls were recruited and genotyped by Polymerase Chain Reaction technique. Odds ratios (OR) and 95% confidence intervals (CIs) were used to access the association between the VEGFA gene polymorphisms and UBC. RESULTS: We found a significant decreased risk association of -2578 C/A polymorphism with UBC (OR (95% CI), 0.62 (0.41-0.94), P = .026) for CA genotype and (OR (95% CI), 0.40 (0.21-0.76), P = .005) for double homozygous mutant genotype. No associations were found in case of both polymorphic sites of VEGF, vis. -2549I/D and +936C/T, respectively. Haplotype analysis revealed a strong linkage disequilibrium between -2578C/A and -2549I/D and CIC combination is the significant haplotype associated with increased risk of UBC (OR (95% CI), 3.63 (1.47-8.97), P = .005). Regarding tumor grade/stage and family history of cancer, no associations were found for -2578C/A polymorphism. CONCLUSION: CIC haplotype of VEGF gene may be important risk factor for UBC development in Tunisia.

Association of FokI polymorphism of vitamin D receptor with urothelial bladder cancer in Tunisians: role of tobacco smoking and plasma vitamin D concentration.

The aim of the study was to test whether the VDR FokI polymorphism is associated with the risk of urothelial bladder cancer (UBC) in Tunisians. The study included 200 unrelated patients with UBC and 200 healthy controls. Genotyping of the VDR FokI polymorphism was determined by PCR-RFLP method. Plasma 25-hydroxyvitamin D concentrations were measured by immunoassay. Binary logistic regression model was applied to test how the association of VDR FokI polymorphism is independent of potential confounding factors. Genotype distribution (FF, 45 vs. 55 %; Ff, 52.1 vs. 47.9 %, and ff, 12 vs. 5.5 %, respectively) and allele frequencies (F, 66.5 vs. 74.8 % and f, 33.5 vs. 25.2 %, respectively) were significantly different between UBC patients and controls. The "ff" genotype [OR (95 % CI), 2.66 (1.24-5.73); p = 0.012] and "f" allele [1.49 (1.09-2.02); p = 0.010] were associated with increased risk of UBC. The association remained significant in multivariate analysis. Stratified analyses showed that VDR FokI polymorphism is only associated with UBC risk in ever-smokers, subjects exposed to chemical carcinogens and those with plasma 25-hydroxyvitamin D over 12 µg/L. The "f" allele of VDR FokI polymorphism is associated with a higher risk of UBC in Tunisians, especially in smokers as well as subjects with occupational exposition and subjects without vitamin D deficiency. These results should be replicated in other ethnic groups and the influence of other genetic factors and environments on this association should be investigated.

Bladder Cancer is Associated with Low Plasma 25-hydroxyvitamin D Concentrations in Tunisian Population.

Little evidence suggests an impact of vitamin D on bladder cancer risk in Caucasians. This study aimed to investigate association of plasma 25-hydroxyvitamin D (25-OHD) with urothelial bladder cancer (UBC) risk in Tunisians. A case-control study included 250 patients with UBC and 250 healthy controls. Plasma 25-OHD was assessed by a competitive chemiluminescence immunoassay. Vitamin D deficiency and insufficiency were defined as 25-OHD <30 nmol/L and 30 to 49.99 nmol/L, respectively. Logistic regression models adjusting for gender, age, smoking status, duration of smoking, occupational exposure, and season were applied. Vitamin D deficiency (50.4% vs. 34.8%; P < 0.001) and insufficiency (40.4% vs. 26.8%; P < 0.001) were more frequent in patients than controls. Multivariate analysis showed that UBC is associated with vitamin D deficiency [odd-ratio (95% confidence interval), 3.71 (1.76-7.80); P = 0.001] and vitamin D insufficiency [2.65 (1.40-5.01); P = 0.003]. Other predictors of UBC were female gender, tobacco use, smoking duration, and occupational exposure. Plasma 25-OHD concentrations are low in Tunisian patients with UBC. These findings support experimental and epidemiological evidence of protective role of vitamin D against UBC but could not ascertain causal relationship. Further prospective studies and clinical trials are warranted to check causality.

Alpha Adducin G460T Variant is a Risk Factor for Hypertension in Tunisian Population.

BACKGROUND: Adducin is a membrane cytoskeletal protein, consisting of three subunits: α, ß, and γ subunits encoded by three different genes (ADD1, ADD2, ADD3). A specific mutation G460T of the α-adducin gene (ADD1) is associated with high renal tubular sodium reabsorption. This mutation is associated with salt sensitivity and may influence the risk of hypertension. In this study, we investigated the relationship between the G460T polymorphism of the ADD1 and essential hypertension (EH) in the Tunisian population. METHODS: The case-controlled study included 280 patients with hypertension and 257 healthy controls. The G460T polymorphism of ADD1 was determined by polymerase chain reaction-restriction fragment length polymorphism analysis method. RESULTS: In the whole population, the genotypic frequencies of the a-adducin G460T polymorphism in hypertensive and control groups (GG, GT, TT) were 78.6%, 17.5%, 3.9% and 87.5%, 11.29%, 1.16%, respectively (χ2 = 9.13, p < 0.01). The genotype was associated with hypertension, OR = 1.79, 95% CI (1.04 - 3.41), p < 0.03 for GT heterozygous and OR = 1.93, 95% CI (1.39 - 2.22), p < 0.03 for TT homozygous. Moreover, when we stratified the population according to gender, the genotypic frequencies were significantly associated with G460T polymorphism in men (p < 0.01) and in women (p < 0.05). Furthermore, no relationship was found between clinical characteristics and ADD1 G460T genotypes. CONCLUSIONS: The present study shows that the a-adducin G460T polymorphism is associated with EH. Our results suggest that this variant can be considered a genetic risk factor for hypertension in the Tunisian population.

Lack of association between FokI polymorphism in vitamin D receptor gene (VDR) & type 2 diabetes mellitus in the Tunisian population.

BACKGROUND & OBJECTIVES: The impact of several environmental and genetic factors on diabetes is well documented. Though the association between the vitamin D receptor (VDR) gene polymorphisms and type 2 diabetes mellitus (T2DM) has been analyzed in different ethnic groups, the results have been inconsistent. The aim of this study was to evaluate the possible association between VDR FokI polymorphism and genetic susceptibility to T2DM in Tunisian population. METHODS: A total of 439 unrelated patients with T2DM and 302 healthy controls were included in the study. Genomic DNA was extracted from blood and genotyped for the single nucleotide polymorphism (SNP) of FokI (T/C: (rs2228570) by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: The genotype distribution and the relative allelic frequencies for the FokI polymorphism were not significantly different between T2DM and controls: in T2DM patients the frequencies of the CC, CT, and TT genotypes were 52.6, 41.0, and 6.1 per cent, respectively, and in controls the genotype frequencies were 55.6, 38.7, and 5.6 per cent, respectively. In our study, the TT genotype of the FokI polymorphism was not associated with T2DM (OR =1.19, 95% CI 0.63 - 2.25, P=0.577). INTERPRETATION & CONCLUSIONS: Our study showed no significant association of the FokI polymorphism in the vitamin D receptor gene with type 2 diabetes mellitus in Tunisian population.

Association Between the G20210A Polymorphism of Prothrombin Gene and Myocardial Infarction in Tunisian Population.

The prothrombin is the precursor of the serine protease thrombin, a key enzyme in homeostasis. Prothrombin G20210A polymorphism (rs1799963) was described as a moderate risk factor for venous thrombosis because this mutation is associated with prothrombin elevated levels which may lead to an imbalance between the procoagulant, anticoagulant, and fibrinolytic system. 20210A carriers have an increased risk of thrombosis. In this study, we proposed to determine the prevalence of 20210A prothrombin variant among Tunisian population, and to evaluate the potential relevance of this variant with myocardial infarction. This study included 1290 unrelated Tunisians (1007 male and 283 female) divided in two groups: Four hundred and eighty-seven MI patients (mean age: 52.64 ± 8.98 years) and 803 apparently healthy controls (mean age: 51 ± 8.99). The prothrombin G20210A polymorphism was carried out by polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) analysis. The distribution of genotypes was in accordance with Hardy-Weinberg equilibrium (p > 0.05). A significant difference in genotype distribution and allele frequency was observed between patients and controls. Male patients with MI had a frequency of 97 % for GG genotype and 3 % for GA+AA genotypes. The control group had a frequency of 99 % for the GG genotype and 1 % for the GA+AA genotypes which is significantly lower than the frequency found in patients (p = 0.01). The same genotype frequencies were found in women (p = 0.032). The MI patient group showed a significantly higher frequency of 20210A allele compared to controls 0.02 versus 0.01 [OR = 3.60 (95 % CI = 1.29-10.53), p = 0.005] in men and 0.015 versus 0.068 [OR = 4.68 (95 % CI = 1.60-14.26), p = 0.001] in women. Our work showed a significant but not independent association between the G20210A polymorphism of the prothrombin gene and MI in the Tunisian population.

Plasma total homocysteine: usual values and main determinants in adults living in the Great Tunis region.

BACKGROUND: Elevated total plasma homocysteine (tHcy) is an established risk factor for occlusive vascular disease and is thought to increase the risk of pregnancy loss, birth defects, and cognitive impairment in the elderly. OBJECTIVES: To determine tHcy standard values and the prevalence of hyperhomocysteinemia (HHC) and to examine their association with demographic and life style factors in the Greater Tunis population. METHODS: This cross-sectional study included 2712 subjects (1228 males and 1484 females) aged 35 - 70 years, living in the Greater Tunis region. tHcy was analyzed by a fluorescent polarizing immunoassay method. HHC was considered as tHcy > or = 15 micromol/L. RESULTS: HHC was observed in 23.7% of subjects. Plasma tHcy was higher in males than females (median (5th - 95th percentile): 13.5 [8.75 - 26.3] micromol/L vs. 10.7 [6.94 - 19.6] micromol/L). The tHcy concentration was significantly increased in smokers, alcoholics, in subjects with vitamin B12 and folate deficiencies, and hyperuricemia. In multivariate analysis, HHC was associated with male gender, vitamin B12 deficiency, clearance of creatinine, alcohol consumption, and hyperuricemia. CONCLUSIONS: HHC is common in Tunisian adults. Male gender, advanced age, renal insufficiency, low vitamin B12 status, hyperuricemia, and alcohol consumption are the main determinants of HHC in this population.

Polymorphisms of the NOS3 gene and risk of myocardial infarction in the Tunisian population.

Controversial results regarding the association of eNOS gene (NOS3) polymorphisms with myocardial infarction (MI) have been reported. This study investigated the relationship of the -786T>C (rs2070744), 894G>T (rs1799983) and 4a4b polymorphisms of the NOS3 gene with the presence of MI in the Tunisian population. In addition, we also examined the association of NOS3 gene haplotypes with MI in Tunisian subjects. A total of 303 patients with MI and 225 controls were included in the study. The 894G>T and -786T>C single nucleotide polymorphisms were analyzed by PCR-RFLP, and 4a4b polymorphism just for PCR. There was significant linkage disequilibrium between the three NOS3 polymorphisms (p<0.0001). The genotype distribution and allele frequency of NOS3 4a4b, but not -786T>C and 894G>T, polymorphism was significantly different between MI patients and controls. The univariate logistic regression analysis showed a significant association of the 4a4b polymorphism and MI according to co-dominant, dominant and recessive models (co-dominant model OR: 4.38, 95%CI: 1.24-15.41; p=0.021, dominant model OR: 1.66, 95%CI: 1.14-2.42); p=0.007, and recessive model OR: 3.85, 95%CI: 1.10-13.47; p=0.035). The multivariate analysis, adjusted for traditional cardiovascular risk factors, revealed that the NOS3 4a4a genotype was an independent predisposing factor to MI, according to the models considered. In addition, a haplotype 7 (C-T-4a), (OR=12.05, p=0.010) was a risk factor of MI after controlling for classical risk factors. These finding suggest that the 4a4b polymorphism of the NOS3 gene was associated with MI in Tunisian patients.

G protein beta3 subunit gene C825T and angiotensin converting enzyme gene insertion/deletion polymorphisms in hypertensive Tunisian population.

BACKGROUND: We investigated the interaction between the G protein beta3 subunit (GNB3) C825T variant and angiotensin converting enzyme (ACE) Insertion/Deletion (I/D) polymorphism in hypertensive Tunisian population. METHODS: Analyses of ACE and GNB3 genotypes were performed in 388 hypertensive patients and 425 healthy controls by polymerase chain reaction-restriction fragment length polymorphism. The plasma ACE activity was determined by a spectrophotometric method. RESULTS: The ACE genotype distribution and allele frequencies were not significantly different between the hypertensive and normotensive subjects (p > 0.05). This polymorphism was not associated with hypertension (HTA) (OR = 0.93, 95% CI = 0.75 - 1.15; p = 0.50). In cases, subjects carrying the DD genotype exhibited higher plasma ACE activity than those with ID and II genotypes (p = 0.001). In this group, a linear regression analysis revealed that the ACE I/D polymorphism is independently associated with plasma ACE activity (p = 0.017). The genotypic distribution and allelic frequencies of the GNB3 C825T polymorphism were not significantly different between the two groups. This polymorphism was found to have no effect on the risk of HTA (OR = 1.14, 95% CI = 0.93 - 1.39; p = 0.21). We did not observe a significant interaction between the GNB3 gene and the ACE gene with HTA. CONCLUSIONS: In this study, the I/D polymorphism is a significant independent predictor for variability of plasma ACE activity but the ACE I/D and GNB3 C825T polymorphisms are not significant factors for HTA in the Tunisian population. Moreover, we found no interaction between ACE D allele and GNB3 825T allele solely or combined with respect to HTA in the Tunisian population.

The role of nutraceuticals in heart failure muscle wasting as a result of inflammatory activity. The International Lipid Expert Panel (ILEP) Position Paper.

Muscle wasting is one of the main causes for exercise intolerance and ventilatory inefficiency in patients with heart failure and a strong predictor of frailty and reduced survival. The prevalence of sarcopenia is at least 20% in patients with heart failure. Patients with heart failure often have subclinical systemic inflammation, which may exert sustained effects on skeletal muscle. Besides exercise, nutrition should also be carefully evaluated as an appropriate diet with selected nutraceuticals may be able to stimulate muscle anabolism and inhibit muscle catabolism. This review summarizes the epidemiological and clinical trial evidence supporting the recommendations for the use of nutraceuticals with anti-inflammatory properties in heart failure and provides an overview of the state of the evidence for nutraceutical supplementation to prevent and/or mitigate heart failure muscle wasting.

Relationship of plasma leptin and adiponectin concentrations with menopausal status in Tunisian women.

To evaluate the effect of menopausal status and body mass index (BMI) on circulating leptin and adiponectin concentrations and investigate whether there is an influence of menopausal transition on the relationships of these adipokines and leptin to adiponectin (L/A) ratio with lipid profile and insulin resistance in a sample of Tunisian women. One hundred ninety-six premenopausal (mean age 35.3±7.6 years) and 180 postmenopausal women (mean age 53.4±6.2 years) were included in the study. Participants were stratified into obese and normal weight groups based upon their baseline BMI. Fasting glucose, HDL-cholesterol (HDL-C), triglycerides (TG), total cholesterol (TC), insulin, leptin, and adiponectin concentrations were measured. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Premenopausal women had significantly higher leptin and L/A ratio and lower adiponectin levels than postmenopausal women. Menopause had no effect on the mean values of BMI, insulin or HOMA-IR, HDL-C, and TG. Using a multiple linear regression model, menopausal status was identified, as significant independent predictor for leptin and adiponectin levels. Irrespective of the menopausal status, obese women exhibited higher leptin and L/A ratio and lower adiponectin levels compared to those with normal weight. Comparison between the two menopausal stages in obese and normal weight groups showed that leptin and L/A ratio decreased, while adiponectin increased from pre- to postmenopausal stage only in obese group. The L/A ratio correlated better with lipid profile and HOMA-IR in postmenopausal stage. The present study showed a significant interaction between menopause and BMI on leptin and adiponectin secretion. Menopausal transition affects the relationships of these adipokines with lipids and insulin resistance.

Association between -786TC polymorphism in the endothelial nitric oxide synthase gene and hypertension in the Tunisian population.

BACKGROUND: Nitric oxide (NO) is produced by endothelial cells and serves as a potent vasodilator. Several lines of evidence have shown that NO plays an important role in the regulation of blood pressure and regional blood flow. Recent genetic studies have shown an association between the -786TC polymorphism in the endothelial nitric oxide synthase gene (NOS3) and coronary artery diseases, but any possible association with hypertension has been controversial. In the present study, we examined a possible association between the -786TC polymorphism of the NOS3 gene and hypertension in a sample of the Tunisian population. METHODS: A total of 288 unrelated Tunisian patients with hypertension and 373 normotensive subjects were included in the study. The -786TC gene polymorphism was analyzed by PCR-RFLP. RESULTS: A significant difference in genotype distribution and allele frequency was observed between patients and controls. Patients with hypertension had a frequency of 19.7% for CC genotype, 52.9% for TC genotype and 27.3% for TT genotype. The control had a frequency of 14.7% for the CC genotype, 47.2% for the TC genotype and 38.1% for the TT genotype (χ²=9.09, p=0.01). The hypertension patient group showed a significant higher frequency of the C allele compared to the controls (0.46 vs. 0.38; χ²=8.26, p=0.004). The odds ratio of hypertension for C vs. T allele frequencies was statistically significant 1.59 (1.14-2.21) at 95% CI, p = 0.004 in men, whereas it was non-significant in women 1.21 (0.87-1.67), p=0.23. CONCLUSION: The present study showed a significant and independent association between the -786TC gene polymorphism (presence of C allele) and hypertension in the Tunisian population.

C(-260)T polymorphism in the promoter of CD 14 gene is not associated with myocardial infarction in the Tunisian population.

Recent findings suggest that inflammation plays a role in atherosclerosis and its acute complications. Several known mechanisms may play at least a partial role in this process. One of the most likely mechanisms involves lipopolysaccharide (LPS) and its receptor, CD14. The C(-260)T single nucleotide polymorphism (rs2569190) in the promoter region of the CD14 receptor gene has been reported to be associated with a higher risk of MI. Others studies, however, have not corroborated these findings. Considering the contradictory results, the aim of the present study was to investigate the possible association between the CD14 C(-260)T polymorphism and the risk of MI in the Tunisian population. A total of 321 Tunisian patients with MI and 344 healthy controls were included in the study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. The frequency of TT homozygous genotype for the CD14 C(-260)T polymorphism was 26.2% in MI patients and 27.0% in the control group. However, the genotype distribution and allele frequencies were not significantly different between MI and controls subjects. Moreover, the odds ratio for MI associated with the TT genotype failed to reach statistical significance (OR=1.22; 95% CI: 0.85-1.77; p=0.272). These results do not support the hypothesis that the C-260T polymorphism of CD14 gene contributes to the genetic susceptibility to MI in the Tunisian population studied.

Association of systemic beta-defensin-1 and -20G/A DEFB1 gene polymorphism with Behçet's disease.

BACKGROUND: Behçet's disease (BD) is a multisystem inflammatory disease of unknown etiology. Beta-defensins are antimicrobial peptides involved in epithelial host defense. To explore whether beta-defensins might be involved in BD pathogenesis, we examined plasma human beta-defensin-1 (hBD-1) and DEFB1 -20G/A polymorphism in BD patients. METHODS: This case-control study included 106 BD patients fulfilling the criteria of the International Study Group for BD and 156 controls. The -20G/A genotypes were determined by PCR-RFLP analysis in all participants, and plasma hBD-1 was assessed by ELISA in 77 BD patients and 44 controls, only. Stepwise multiple regression models were applied to determine independent predictors for plasma hBD-1 in BD patients. RESULTS: Distribution of -20G/A genotypes was different between BD patients and controls. Compared to GG genotype, "GA" genotype [OR (95% CI), 3.12 (1.56-6.16); p = .001] and "AA" genotype [2.57 (1.10-5.96); p = .027)] were associated with increased risk for BD. Plasma hBD-1 concentrations were significantly higher in BD patients than controls (9.81 ±â€¯3.52 ng/mL vs. 5.30 ±â€¯3.02 ng/mL; p < .001), and in BD patients with neurological involvement than those without (11.1 ±â€¯4.12 ng/mL vs. 9.19 ±â€¯3.10 ng/mL; p = .040). No variation was noted according to other clinical features, treatment received or -20G/A genotypes. In multivariate analysis, neurological involvement was the only predictor for plasma hBD-1 (ß, 0.274; p = .029). CONCLUSIONS: Findings suggest that hBD-1 and its encoding gene DEFB1 could modulate the risk for BD, especially for BD neurological involvement. Further work is needed for a better understanding of role of hBD-1 and its genetic variants in the pathogenesis of BD.