Plasma lipid peroxidation products and antioxidant enzyme activities in patients with type 2 diabetes mellitus.

Diabetes is associated with a significant increase in thiobarbituric acid reactive substances (TBARS) which are considered as an index of endogenous lipid peroxidation. The human body has a complex antioxidant defense system that prevents the initiation of free radical chain reactions. We measured plasma TBARS levels, superoxide dismutase (SOD) and catalase (CAT) activities and compared their relation to the metabolic control of diabetes and diabetic microangiopathy. Sixty-four patients (19 men), aged 52.35+/-9.31 years with type 2 diabetes mellitus were included in the study. Thirty-six healthy subjects (12 men), aged 51.02+/-7.01 years formed the control group. TBARS levels and SOD activity were elevated in the diabetic group when compared with the control group ( p<0.001 and p<0.00001, respectively). However CAT activity was significantly decreased in the diabetic group when compared with the control group ( p<0.00001). Patients with diabetic nephropathy and retinopathy, but not neuropathy, had elevated TBARS levels but there was no statistically significant difference when compared with diabetic patients without microangiopathy ( p>0.05). There was a positive correlation between plasma TBARS levels and SOD activity (r=0.770, p=0.0001) and a negative correlation between plasma TBARS levels and CAT activity (r=0.482, p=0.0001). There was also a negative correlation between SOD and CAT activities (r=-0.609, p=0.0001). We found significantly elevated TBARS levels in diabetic patients. We did not observe any correlation between TBARS levels and blood glucose and HbA(1c) levels. Elevated TBARS levels and SOD activity and decreased CAT activity may be due to a compensation mechanism of the body.

The effects of aprotinin and steroids on generation of cytokines during coronary artery surgery.

OBJECTIVE: To compare the efficacy of aprotinin and methylprednisolone in reducing cardiopulmonary bypass (CPB)-induced cytokine release, to evaluate the effect of myocardial cytokine release on systemic cytokine levels, and to determine the influence of cytokine release on perioperative and postoperative hemodynamics. DESIGN: Prospective, randomized clinical trial. SETTING: University teaching hospital and clinics. PARTICIPANTS: Thirty patients undergoing elective coronary artery bypass graft surgery. INTERVENTION: Patients were randomly allocated into groups treated with aprotinin (n = 10) or methylprednisolone (n = 10) or into an untreated control group (n = 10). Aprotinin-treated patients received aprotinin as a high-dose regimen (6 x 10(6) KIU), and methylprednisolone-treated patients received methylprednisolone (30 mg/kg intravenously) before CPB. MEASUREMENTS AND MAIN RESULTS: Patients were analyzed for hemodynamic changes and alveolar-arterial PO2 difference (AaDO2) until the first postoperative day. Plasma levels of proinflammatory cytokines (tumor necrosis factor [TNF]-alpha, interleukin [IL]-1beta, IL-6, and IL-8) were measured in peripheral arterial blood immediately before the induction of anesthesia, 5 minutes before CPB, 3 minutes after the start of CPB, 2 minutes after the release of the aortic cross-clamp, 1 hour after CPB, 6 hours after CPB, and 24 hours after CPB; and in coronary sinus blood immediately before CPB and 2 minutes after the release of the aortic cross-clamp. The hemodynamic parameters did not differ among the groups throughout the study. After CPB, AaDO2 significantly increased (p < 0.05) in all groups. A significant decrease in AaDO2 was observed in aprotinin-treated patients at 24 hours after CPB compared with the other groups (p < 0.05). TNF-alpha level from peripheral arterial blood significantly increased in control patients 1 hour after CPB (p < 0.01) and did not significantly increase in methylprednisolone-treated patients throughout the study. In all groups, IL-6 levels increased after the release of the aortic cross-clamp and reached peak values 6 hours after CPB. At 6 hours after CPB, the increase in IL-6 levels in methylprednisolone-treated patients was significantly less compared with levels measured in control patients and aprotinin-treated patients (p < 0.001). In control patients, IL-8 levels significantly increased 2 minutes after the release of the aortic cross-clamp (p < 0.05), and peak values were observed 1 hour after CPB (p < 0.01). IL-8 levels in control patients were significantly higher compared with patients treated with aprotinin and patients treated with methylprednisolone 1 hour after CPB (p < 0.05). CONCLUSION: This study showed that methylprednisolone suppresses TNF-alpha, IL-6, and IL-8 release; however, aprotinin attenuates IL-8 release alone. Methylprednisolone does not produce any additional positive hemodynamic and pulmonary effects. An improved postoperative AaDO2 was observed with the use of aprotinin.

The relation between plasma endothelin-1 levels and metabolic control, risk factors, treatment modalities, and diabetic microangiopathy in patients with Type 2 diabetes mellitus.

We evaluated the possible relation between plasma endothelin-1 (ET-1) levels and metabolic control, risk factors, treatment modalities, and diabetic microangiopathy, including nephropathy, neuropathy, and retinopathy in patients with Type 2 diabetes and healthy control group. Sixty-eight (39 females and 29 males) patients with Type 2 diabetes and 14 (6 females and 8 males) healthy subjects were included in the study. Plasma ET-1 levels were found to be 10.46+/-1.24 pmol/l in the diabetic group, whereas 7.97+/-0.41 pmol/l in the control group, which was statistically significant (P<.01). We also found elevated plasma ET-1 levels in patients with the least one microvascular complication when compared with the uncomplicated diabetes group (P=.02). Moreover, plasma ET-1 levels of the uncomplicated group was higher than the control group (P<.05). Plasma ET-1 levels were significantly elevated in hypertensive diabetics than normotensive diabetics (t=2.58, P=.012). It was also found to be elevated in diabetic patients with diabetes duration of more than 10 years when compared with patients less than 10 years (P=.02). These findings can be interpreted as the increased damage of microvascular complications in the disease process that may lead to elevated ET-1 levels. Mean plasma ET-1 levels in diabetic patients with a family history of diabetes was found to be higher than patients with no family history of diabetes. Genetical and environmental factors may have an effect on ET-1 level. We also studied the correlations of plasma ET-1 levels on age, sex, fasting blood glucose levels, treatment modalities HbA1c, hyperlipidemia, C-peptide, Body Mass Index, and smoking, but did not find any statistically significant difference. In conclusion, plasma ET-1 levels are well correlated with microangiopathy, hypertension, increased disease duration, and family history of diabetes, but poorly correlated with metabolic control, treatment modalities, age, sex, hyperlipidemia, obesity, and smoking.

Concentrations of copper, zinc and various elements in serum of patients with bronchial asthma.

In this study, serum copper, zinc, magnesium, iron and calcium concentrations were investigated in 40 patients with bronchial asthma (BA) and in 43 healthy subjects. Copper and calcium levels were found to be increased in patients with BA compared to the control group (p < 0.001 and p < 0.001 respectively). On the other hand, the serum zinc level was significantly lower in healthy subjects (p < 0.01). No changes were found in serum magnesium and iron levels in patients with BA compared to controls. In addition to various elements, certain serum proteins such as albumin, transferrin and ferritin were also assessed to determine whether there was a relationship between the elements and proteins in patients with BA. There was only a significant decrease in albumin concentration in patients with BA (p < 0.05).

Quantification of nitric oxide and cytokines in rabbit aqueous humor after neodymium:YAG laser capsulotomy.

PURPOSE: The purpose of this study was to evaluate the presence of nitric oxide (NO) and cytokines such as interleukin 1 beta, interleukin 2 receptor (IL-2R), interleukin 6 and tumor necrosis factor alpha on aqueous humor after neodymium:YAG (Nd:YAG) laser posterior capsulotomy. METHODS: Fifteen rabbits (30 eyes) with dense posterior capsule opacities underwent Nd:YAG capsulotomy 4 months after phacoemulsification cataract surgery. After general and topical anesthesia, Nd:YAG capsulotomy was performed using an equal number of shots and power setting on all eyes. Aqueous humor specimens were collected from each eye preoperatively and at 12, 24 and 48 h after the surgery to determine NO and cytokine levels. RESULTS: The levels of NO and cytokines except IL-2R were significantly high as compared to preoperative levels in all eyes at 12 and 24 h postoperatively (p < 0.05). Although the levels of NO and cytokines were higher than preoperative levels at 48 h, the differences were not statistically significant (p > 0.05). CONCLUSION: These findings suggest that NO and cytokines appear to be potential inflammatory mediators in the occurrence of early inflammation following Nd:YAG posterior capsulotomy.

Effects of NG-nitro L-arginine and corticosteroids on aqueous humor levels of nitric oxide and cytokines after cataract surgery.

PURPOSE: To assess the efficacy of nitric oxide synthesis (NOS) inhibitor, topical steroids, and nonsteroidal anti-inflammatory drugs on aqueous levels of nitric oxide (NO) and cytokines after cataract surgery. SETTING: Research Laboratory, Inonu University Turgut Ozal Medical Center, Malatya, Turkey. METHODS: Fifteen rabbits had intercapsular phacoemulsification and were randomly divided into 3 treatment groups: Group 1 was treated with topical prednisolone acetate 1% drops 5 times a day for 1 week; Group 2, flurbiprofen 0.03% drops 5 times a day for 1 week; Group 3, a 0.1 cc subconjunctival injection of NG-nitro L-arginine (L-NAME) (150 mg/kg) 1 day and 3 days after surgery. Three rabbits serving as controls received a subconjunctival injection of an equal volume of balanced salt solution (BSS) at the same times as the L-NAME injections. Aqueous humor specimens were collected from each eye to determine NO and cytokine levels including interleukin-1-beta (IL-1 beta), interleukin-2R (IL-2R), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha). RESULTS: The levels of IL-1 beta and IL-6 were higher in Group 2 and the control group than in Groups 1 and 3 at all times. The differences were not statistically significant (P < .05). Nitric oxide and TNF-alpha levels in Groups 1 and 3 were significantly lower than in Groups 2 and the controls 1, 3, and 7 days postoperatively (P < .05). CONCLUSION: These findings suggest a strong inhibitory effect of NOS inhibitors and corticosteroids on aqueous levels of TNF-alpha and NO and no inhibitory effect on IL-1 beta and IL-6 levels after cataract surgery.

Effects of 1,25 (OH)2D3 treatment on lipid levels in uremic hemodialysis patients.

The aim of this study was to evaluate the effect of 1,25 (OH)2D3 treatment on lipid levels in uremic hemodialysis (HD) patients. Thirty-one HD patients who had never been treated with vitamin D nor related drugs and 12 healthy subjects with normal renal functions were studied. Uremic HD patients were randomly divided into two groups. Sixteen uremic HD patients were treated with oral calcitriol (0.5 micrograms/day) for 8 weeks. 13 uremic HD patients and 12 healthy subjects were given placebo. In all these cases before and after 8 weeks of treatments; serum total lipid, total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride levels were determined. After calcitriol treatment, triglyceride levels were significantly decreased. But total lipid, cholesterol, HDL-cholesterol and LDL-cholesterol levels did not significantly change. In the other two groups there were no significant changes. These results show that calcitriol treatment has a positive effect on triglyceride levels in uremic HD patients. This effect of mechanism of calcitriol treatment has not been known yet. But it could be due to regulation carbohydrates metabolism and normalization of parathormone (PTH) levels.