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Type 2 diabetes is frequently associated with an inflammatory status; the relationships between low-grade inflammation and diabetic nephropathy are still unclear. The aim of this study was to evaluate the relationships between acute-phase markers of inflammation, glomerular structure, and albumin excretion rate (AER) in type 2 diabetes. In 74 patients with type 2 diabetes (23 normoalbuminuric, 30 microalbuminuric, and 21 proteinuric) fibrinogen, serum amyloid A protein (SAA), C-reactive protein (CRP), and IL-6 were determined. AER was measured on three 24-h urine collections; GFR was measured by 51 Cr EDTA plasma clearance. A kidney biopsy was performed, and mesangial fractional volume [Vv(mes/glom)] and glomerular basement membrane (GBM) width were estimated by electron microscopic morphometric analysis. CRP, fibrinogen, SAA, and IL-6 differed among groups, with proteinuric patients having the highest levels. SAA and fibrinogen correlated with AER (P < 0.03 and P < 0.001, respectively). GBM width and Vv(mes/glom) increased from normoalbuminuric to proteinuric patients [P < 0.005 normoalbuminuric and microalbuminuric versus proteinuric for GBM, P < 0.01 normoalbuminuric versus proteinuric for Vv(mes/glom)]. In patients with increased GBM width (>396 nm), CRP, SAA, and IL-6 were higher than in patients with normal GBM width (P < 0.003, P < 0.004, and P < 0.0004, respectively). GBM width was directly correlated with fibrinogen (r ‫؍‬ 0.33, P < 0.002) and IL-6 (r ‫؍‬ 0.25 P < 0.05). In conclusion, this study demonstrates that acute-phase markers of inflammation are associated with nephropathy status and GBM thickening, suggesting a role for inflammation in the pathogenesis of diabetic glomerulopathy. T ype 2 diabetes is frequently associated with an acutephase reaction, suggestive of a low-grade inflammatory status (1,2). In fact, markers of acute-phase response, including serum amyloid A (SAA), C-reactive protein (CRP), and IL-6, the main mediators of the response, have been shown to be elevated in patients with type 2 diabetes and with the metabolic syndrome (2). It is well known that in the general population, as well as in diabetes, these acute-phase markers are associated with increased cardiovascular risk, because chronic inflammation is one of the pathogenetic mechanisms of atherosclerosis (3). In contrast, the relationships between lowgrade inflammation and diabetic microangiopathy are still unclear. As far as nephropathy is concerned, several studies have examined the relationships with inflammation, leading to conflicting results (4 -11). Overall, however, most studies have reported an increase in acute-phase markers in patients with nephropathy and also in patients with microalbuminuria (5,7-9). The coexistence of an inflammatory condition with diabetic nephropathy could explain in part the tremendously increased cardiovascular risk among these patients.Also fibrinogen has been reported to be associated with both cardiovascular risk and nephropathy in type 1 and type 2 diabetes (10,11). The Diabetes Cont...

Contrasting information has been reported concerning the course of renal function in NIDDM with hypertension alone or in association with renal damage. The aim of the present study was to elucidate the course of the glomerular filtration rate (GFR) in hypertensive NIDDM patients during antihypertensive therapy. Furthermore, we compared the effects of ACE inhibitors (cilazapril, Inibace, Roche, Milan, Italy) and Ca(2+)-channel blockers (amlodipine, Norvasc, Pfizer, Rome, Italy). Of the hypertensive NIDDM patients attending the outpatient's clinic of the internal medicine departments of the University of Padova and Sassari, 44 participated in the present study. Of these patients, 26 were normoalbuminuric and 18 microalbuminuric. They were randomly treated with either cilazapril or amlodipine. The target of antihypertensive treatment was a value < 140 mmHg for systolic and 85 mmHg for diastolic blood pressure (BP). Microalbuminuria was defined as an albumin excretion rate (AER) between 20 and 200 micrograms/min. GFR was measured by plasma clearance of 51Cr-labeled EDTA at baseline and every 6-12 months during a 3-year follow-up interval. A significant decrease was observed in the values of GFR, AER, and systolic and diastolic BP in normoalbuminuric and microalbuminuric patients during antihypertensive therapy. The GFR fall in the overall population of NIDDM patients was significantly and inversely related to the decrease of mean BP (diastolic + 1/3 pulse pressure) (r = -0.80, P < 0.0001) but not to that of HbA1c, triglycerides, and BMI. The GFR decline (mean +/- SE) per year in the normoalbuminuric patient was 2.03 +/- 0.66 ml.min-1 x 1.73 m-2 (95% CI 0.92-3.17) during cilazapril and 2.01 +/- 0.71 ml.min-1 x 1.73 m-2 (95% CI 0.82-3.11) during amlodipine therapy. The GFR decline per year in the microalbuminuric patient was 2.15 +/- 0.69 ml.min-1 x 1.73 m-2 (95% CI 0.86-3.89) during cilazapril and 2.33 +/- 0.83 ml.min-1 x 1.73 m-2 per year (95% CI 1.03-3.67) during amlodipine therapy. Cilazapril and amlodipine lowered AER to a similar extent in normoalbuminuric and microalbuminuric patients. No significant changes were observed concerning other clinical and biochemical features between the two antihypertensive therapies and particularly HbA1c, BMI, triglycerides, and cholesterol plasma values. These results support the tenet that arterial hypertension plays a pivotal role in contributing to renal damage in NIDDM, even when AER is normal. However, the degree of BP control, with both cilazapril and amlodipine, can successfully delay the slope of GFR decline in hypertensive NIDDM patients with or without incipient nephropathy.

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Resistance to the metabolic effects of insulin has been reported with regard to glucose disposal in type I diabetic patients (IDDM) even when they were euglycemic. Our aim was to study glucose, lipid, and amino acid metabolism during glucose clamping at multiple levels of insulin in 10 normal (N) and 6 IDDM patients. Blood glucose was maintained constant (4.7 mmol/liter) at three insulin plateaus (160 min each) [42 +/- 6 (SD) 89 +/- 11, and 1255 +/- 185 microU/ml in N and 36 +/- 4, 80 +/- 13, and 1249 +/- 107 microU/liter in IDDM]. Mean glucose disposal was 34 +/- 11, 69 +/- 10, and 84 +/- 22 mumol kg-1 min-1 in N and 16 +/- 5, 40 +/- 18, and 65 +/- 27 in IDDM, respectively. Baseline concentrations of blood lactate, pyruvate, alanine, and branched chain amino acids were 560 +/- 130, 36 +/- 9, 212 +/- 44, and 451 +/- 19 mumol/liter, in N and 793 +/- 179 (P less than 0.05), 45 +/- 14, 195 +/- 50, and 439 +/- 33 in IDDM, respectively. The maximum percent change of lactate during the euglycemic clamp was +147 +/- 23% in N and +75 +/- 15% (P less than 0.05) in IDDM; that of branched chain amino acids was -61 +/- 5% in N and -48 +/- 7% (P less than 0.01) in IDDM. Baseline concentrations of glycerol, FFA, and adipate were 44 +/- 15, 449 +/- 152, and 8 - 8 mumol/liter in N and 39 +/- 14, 473 +/- 44, and 41 +/- 14 (P less than 0.01) in IDDM. The maximum percent change of glycerol during the euglycemic clamp was -50 +/- 8% in N and -16 +/- 8% (P less than 0.01) in IDDM, that of FFA -98 +/- 3% in N and -70 +/- 4% in IDDM (P less than 0.05). No significant differences were found between N and IDDM with regard to blood concentrations of ketone bodies, citrate, ketoglutarate, and hydroxymethylglutaryl coenzyme A both before and during the euglycemic clamp. The lactate percent increase was significantly correlated to glucose disposal rate (P less than 0.001). The lactate turnover rate increased during the euglycemic clamp and was lower in IDDM than in N. We conclude that during euglycemic-multiple insulin clamp studies the greater lactate increase suggests that the flux of glycolysis is higher in N than in IDDM, tricarboxylic acid concentrations are comparable in N and IDDM, and FFA, glycerol, and branched chain amino acid decreases were less in IDDM than in N, suggesting that IDDM patients are resistant to insulin with regard to lipid and protein metabolism. The higher adipate basal values demonstrate enhanced omega-oxidation in IDDM.