Impaired nitric oxide production in patients with primary open-angle glaucoma.

BACKGROUND: Glaucoma is an optic neuropathy induced by many factors. Vascular dysfunction is involved in the mechanism underlying glaucoma. AIM: To determine the involvement of nitric oxide (NO), which is implicated in the regulation of ocular blood flow, in primary open angle glaucoma (POAG). Furthermore, lactate and uric acid (UA) levels were investigated. METHODS: Concentrations of NO, UA and lactate in plasma and aqueous humor (AH) were measured in 214 Tunisian patients (100 patients with POAG and 114 subjects with cataract as control group). NO metabolites, nitrate and nitrite (NOx) production were determined using the Griess reaction. UA and lactate concentrations were measured using enzymatic- colorimetric methods. RESULTS: NOx concentrations in patients with POAG were significantly lower compared to cataract group in plasma (5.23±1.55 µmol/L vs 18.35±6.87 µmol/L, p=0.01) and AH (20.54±7.41 µmol/L vs 45.25±10.92 µmol/L, p=0.02). Plasma and AH levels of lactate and UA were significantly higher in glaucoma patients than in control subjects. CONCLUSIONS: In the present study, decreased NO and increased UA and lactate levels were found in the AH and plasma of POAG patients compared to control subjects. These data suggest a possible involvement of these factors in glaucoma.

Comparison between electronic cigarette refill liquid and nicotine on metabolic parameters in rats.

AIMS: Nicotine is known to promote body weight loss and to disturb glucose homeostasis and lipoprotein metabolism. Electronic cigarettes, as a substitute to nicotine, are becoming increasingly popular, although there is no evidence regarding their safety. Considering the dearth of information about e-cigarette toxicity, the present study was designed to compare nicotine alone to e-liquid with or without nicotine on metabolic parameters in Wistar rats. MAIN METHODS: For this purpose, e-liquid with or without nicotine and nicotine alone (0.5mg/kg of body weight) were administered intra-peritoneally during 28 days. KEY FINDINGS: Our results show a significant decrease in food and energy intake after nicotine or e-liquid with nicotine exposure, when compared to control or e-liquid without nicotine. Analysis of lipid status identified a significant decrease in cholesterol and LDL levels in e-cigarette groups, suggesting an improvement in lipid profile. Interestingly, e-liquid without nicotine induced hyperglycemia which is negatively correlated to hepatic glycogen level, acting like nicotine alone. Furthermore, an increase in liver biomarkers was observed in all treated groups. qRT-PCR analysis showed GSK3ß up-regulation in e-liquid with nicotine as well as, surprisingly, in e-liquid without nicotine exposure. In contrast, PEPCK genes were only up-regulated in e-liquid with nicotine. SIGNIFICANCE: While some features observed in rats may not be observed in human smokers, most of our data are consistent with, e-liquid per se i.e. without nicotine, not being neutral from a metabolic stand point since disrupting glucose homeostasis in rats.

Serum lipid level in Tunisian patients with psoriasis.

BACKGROUND: Psoriasis is a common chronic inflammatory skin disorder that has been associated with oxidative stress, abnormal plasma lipid metabolism, and high frequency of cardiovascular events. The aim of this study was to determine lipid profile variations in Tunisian psoriatic patients. METHODS: This study was designed and conducted as a case-control assay with 91 psoriatic patients and 91 controls. The lipid profiles, including serum level of triglycerides, cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL), were assessed in both groups. RESULTS: The two groups consisted of 91 patients and 91 controls, each with 45 males and 46 females. In the psoriatic group, serum triglycerides, low density lipoprotein, and very low density lipoprotein cholesterol were significantly higher than in the control group (p < 0.05), while the high density lipoprotein cholesterol (HDL-cholesterol) was significantly decreased in patients with psoriasis compared to controls (p < 0.001). There were no significant differences concerning insulin or insulin resistance and total cholesterol between the two groups. The insulin secretion was significantly higher in patients with psoriasis than in the control group (p = 0.003). However, there was no significant correlation between severity of psoriasis and serum lipid and insulin secretion. A negative correlation (r = -0.253, p = 0.019) was found between PASI index and HDL-C. CONCLUSIONS: A high serum lipid level is significantly more common in psoriatic patients. This could be responsible for higher prevalence of cardiovascular incidents in psoriatic patients. It may be useful to do early screening and treatment of hyperlipidaemia in psoriatic patients to prevent atherosclerosis and its complications.

Psoriasis is associated with increased Framingham ten-year risk score for coronary heart disease in Tunisians.

BACKGROUND: To assess the ten-year cardiovascular risk for coronary heart disease (CHD) in psoriatic patients and to test the impact of psoriasis severity and duration on cardiovascular risk. METHODS: A case-control study included 202 adult psoriatic patients and 202 controls. RESULTS: Risk CHD was estimated using the Framingham risk score algorithm. Patients had a higher ten-year Framingham risk score (13.62 +/- 11.86 vs. 9.23 +/- 8.04; p = 0.002) than controls. In addition, a high risk score and a very high risk score (> 40%) were more frequent in psoriatic patients compared with controls (p = 0.043 and p < 0.001, respectively). According to the severity of psoriasis, the ten-year cardiovascular risk increases progressively and significantly (11.84 +/- 10.08; 15.59 +/- 11.79 and 16.92 +/- 14.13 for mild, moderate and severe psoriasis, respectively). CONCLUSIONS: Psoriatic patients have significantly greater risks of developing coronary heart disease than controls in relationship with psoriasis comorbidities such as hypertension, diabetes, dyslipidemia, inflammation and probably with psoriasis itself.

Phenylketonuria is still a major cause of mental retardation in Tunisia despite the possibility of treatment.

BACKGROUND AND OBJECTIVE: Accumulation of phenylalanine following a deficiency of phenylalanine hydroxylase activity generates a brain damage with mental retardation: phenylketonuria (PKU). In the developing countries, where PKU systematic neonatal screening program is not established yet, the management of PKU handicap is not properly carried out. The aim of this study was to estimate the frequency of the PKU diagnosed following clinical features anomalies, to provide information about the untreated PKU patients profile in Tunisia not covered by neonatal screening. Also it is stressed that treated patients have a normal development. PATIENTS AND METHODS: This is a retrospective study of 156 cases of PKU detected in Tunisia over 20 years following symptoms suggestive of inherited metabolic disease. Phenylalaninemia level was performed by fluorometric method. Among them 9 patients were treated. RESULTS: The PKU estimated frequency was 1/7631. The diagnosis mean age was 4 years. The phenylalaninemia mean was 1680 µmol/L; the classical PKU form accounted for 85.3% of cases and the dominant clinical symptoms were: mental retardation (88.2%), motor delays (87.7%), speech difficulties (83.2%) and pigmentation anomalies (61.7%). The treated patients responded to treatment and showed a normal development. CONCLUSION: The establishment of neonatal screening should be a priority to avoid cases of mentally retardation.