A Randomized Trial of Low-Protein Diet in Type 1 and in Type 2 Diabetes Mellitus Patients With Incipient and Overt Nephropathy
ABSTRACT The efficacy of a low-protein diet in the secondary prevention of diabetic nephropathy is not established in patients with type 1 or type 2 diabetes mellitus. To determine whether a low-protein diet slows the decrease in glomerular filtration rate (GFR) and decreases the albumin excretion rate (AER) in diabetic patients with incipient and overt nephropathy, we performed a 2-year prospective, randomized controlled trial comparing the effects of a low-protein diet (0.8 g/kg/day) with a usual-protein diet.
The study was conducted in a University hospital and included 63 type 1 and type 2 diabetic patients with either incipient or overt nephropathy and mild renal failure (prestudy GFR, 80 +/- 20 mL/min). The primary outcome measures were decreased in GFR and 24-hour AER.
In the low-protein-diet group, patients were younger (52 +/- 12 versus 63 +/- 9 years old) and more often were type 2 diabetic. During the follow-up period, according to dietary records the low-protein-diet group consumed 16% +/- 3% of total caloric intakes as compared with 19% +/- 4% in the usual-protein-diet group (P < .02), but 24-hour urinary urea excretions did not differ between the two groups. The 2-year GFR decrease was 7 +/- 11 mL/min in the low-protein-diet group and 5 +/- 15 mL/min in the usual-protein-diet group (P = not significant). AER did not increase significantly in the two diet groups during the follow-up period. Blood pressure and glycemic control were similar in the two groups all along the study. The decrease in GFR and AER were also similar in 6 compliant patients according to dietary records and to 24-hour urinary urea excretions from the low-protein-diet group and in 12 patients from the usual-protein-diet group.
A 2-year low-protein diet did not alter the course of GFR or of AER in diabetic patients with incipient or overt nephropathy receiving renin-angiotensin blockers with strict blood pressure control.
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- "Thus, the treatment strategies for renal failure, including the use of protein-restricted diets , have gained increased interest for the treatment of patients with diabetic nephropathy. Despite the few studies that suggest that protein intake restriction fails to improve renal prognosis in type 1 or type 2 diabetic patients with incipient or overt nephropathy and confers renoprotection, several findings have demonstrated that a low-protein diet preserves renal function and structure in animal models  and in type 2 diabetic patients with macroalbuminuria and improves disease prognosis, low-grade inflammation and proteinuria and depressive symptoms. However, there has been increasing concern regarding the risk of the subsequent development of malnutrition due to these diets. "
ABSTRACT: A low-protein diet supplemented with ketoacids maintains nutritional status in patients with diabetic nephropathy. The activation of autophagy has been shown in the skeletal muscle of diabetic and uremic rats. This study aimed to determine whether a low-protein diet supplemented with ketoacids improves muscle atrophy and decreases the increased autophagy observed in rats with type 2 diabetic nephropathy. In this study, 24-week-old Goto-Kakizaki male rats were randomly divided into groups that received either a normal protein diet (NPD group), a low-protein diet (LPD group) or a low-protein diet supplemented with ketoacids (LPD+KA group) for 24 weeks. Age- and weight-matched Wistar rats served as control animals and received a normal protein diet (control group). We found that protein restriction attenuated proteinuria and decreased blood urea nitrogen and serum creatinine levels. Compared with the NPD and LPD groups, the LPD+KA group showed a delay in body weight loss, an attenuation in soleus muscle mass loss and a decrease of the mean cross-sectional area of soleus muscle fibers. The mRNA and protein expression of autophagy-related genes, such as Beclin-1, LC3B, Bnip3, p62 and Cathepsin L, were increased in the soleus muscle of GK rats fed with NPD compared to Wistar rats. Importantly, LPD resulted in a slight reduction in the expression of autophagy-related genes; however, these differences were not statistically significant. In addition, LPD+KA abolished the upregulation of autophagy-related gene expression. Furthermore, the activation of autophagy in the NPD and LPD groups was confirmed by the appearance of autophagosomes or autolysosomes using electron microscopy, when compared with the Control and LPD+KA groups. Our results showed that LPD+KA abolished the activation of autophagy in skeletal muscle and decreased muscle loss in rats with type 2 diabetic nephropathy.PLoS ONE 11/2013; 8(11):e81464. DOI:10.1371/journal.pone.0081464 · 3.23 Impact Factor
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ABSTRACT: Ausgehend von der allgemeinen Kaiserschen Definition der Nachweisgrenze und der Garantiegrenze fr Reinheit in der analytischen Chemie wird die Berechnung dieser Gren im speziellen Fall der Emissionsspektrographie dargelegt. Insbesondere wird auf die praktische Bestimmung des mittleren Blindwertes und der Blindwertschwankungen eingegangen und am Beispiel von Antimonspektren gezeigt, da auch bei einem ungleichmigen Bandenuntergrund die Krnigkeitsfluktuationen der photographischen Emulsion die die Nachweisgrenze bestimmenden Blindwertschwankungen sein knnen. Ein einfaches Verfahren zur Ermittlung dieser Fluktuationen wird angegeben und dabei besonders auf die Voraussetzungen fr diese Arbeitsweise hingewiesen.The calculation of analytical limits of detection and limits of guarantee for purity in emission spectrography—based on Kaiser's general definitions—is shown. Especially the estimate of the mean value and the standard deviation of blanks is discussed. Spectra of antimony are given as an example to demonstrate that even in presence of a non-uniform background produced by bands the graininess-of the photographic emulsion may be the predominating factor for blank fluctuations. A simple procedure for estimating these fluctuations is recommended, the presumptions of the method are pointed out particularly.Fresenius Journal of Analytical Chemistry 06/1966; 220(4):260-272. DOI:10.1007/BF00513179
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ABSTRACT: Type 2 diabetes mellitus and hypertension are frequently associated. Cardiovascular morbidity is a major burden in these patients. Furthermore a renal disease appears in 40% of them that may lead to chronic terminal renal failure. Whatever the stage of the renal disease, it increases the cardiovascular risk. A majority of type 2 diabetic patients will eventually died of cardiovascular complications before having reached chronic terminal renal failure. Many large clinical trials including type 2 diabetic patients with hypertension have been performed in the last 20 years with cardiovascular morbidity and mortality as primary outcomes. These trials mainly evaluated the role of glycemic control, of hypertension as well as the decrease of LDL-cholesterol. Based on these trials, the prescription type of hypertensive type 2 diabetic patient should include, besides hygienic and dietary advices, antidiabetic treatment, thiazide and/or betablocker and platelet inhibitor. Statin should be prescribed for secondary prevention if serum LDL-cholesterol is above 1,3 g/l and for primary prevention depending on serum LDL-cholesterol and on the number of cardiovascular risk factors. The objectives are an HbA1c below 6,5%, a LDL-cholesterol below 1g/l and a blood pressure below 150/80 mmHg. The appearance of diabetic nephropathy alters the treatment and the therapeutic objectives. Many large trials aimed at preventing microalbuminuria (primary prevention), macroproteinuria (secondary prevention), and chronic renal failure (tertiary prevention) have been conducted. For primary prevention, angiotensin-converting-enzyme inhibitors should be prescribed in case of hypertension because they delay the appearance of microalbuminuria. For secondary prevention, angiotensin-converting-enzyme inhibitors and angiotensin-receptor blockers decrease albuminuria excretion rate and delay the appearance of macroproteinuria whatever the blood pressure. Tertiary prevention is based on angiotensin-receptor blockers since they slow down the decrease of renal function. The objectives are a blood pressure below 130/80 mmHg and the regression or the reduction of albuminuria excretion rate. Intensified and target-driven interventions aimed at multiple risk factors implicated in cardiovascular and renal lesions, as successfully performed in the STENO-2 study, reduce the risk of cardiovascular and renal morbidity and mortality. In this article, large clinical trials having the prevention of cardiovascular and renal risks as primary outcomes were analyzed.NÃ©phrologie & ThÃ©rapeutique 05/2006; 2(2):51-74. DOI:10.1016/j.nephro.2006.01.004 · 0.40 Impact Factor