Low-protein diet improves blood and urinary glucose levels and renal manifestations of diabetes in C57BLKS-db/db mice

Abstract

Low-protein intake in the range used by humans may relieve renal manifestations through the suppressed expression of genes in the renal RA system of CT mice. On the other hand, in db mice, low-protein intake improved hyperglycemia and the renal manifestations of diabetes.

Deteriorated glucose metabolism with a high-protein, low-carbohydrate diet in db mice, an animal model of type 2 diabetes, might be caused by insufficient insulin secretion

“…In our previous study, a high-protein diet led to deterioration of glucose metabolism, but lowered BW in db mice under pair-fed conditions for 10 weeks [12]. Therefore, we now investigated how diets with varying protein and carbohydrate contents may affect the diabetic condition of db mice for a shorter duration without also affecting BW.…”

“…Therefore, we previously examined the effect of clinically relevant dietary protein content diets (12-24 % energy) on glucose levels and renal manifestations in db mice, an animal model for DM exhibiting leptin receptor deficiency and a relatively low capacity for insulin secretion [10,11]. We found that a high-protein, low-carbohydrate diet increased blood glucose levels and deteriorated renal manifestations, in contrast to a low-protein, highcarbohydrate diet [12]. Similarly, a human study revealed that a high-protein diet led to highly advanced glycation, often resulting in HbA1c production [13].…”

Effects of Diets with Different Proportions of Protein/ Carbohydrate on Retinal Manifestations in db Mice

“…Of them, db mice are deficient in the leptin receptor and show retinopathy and nephropathy caused by type 2 diabetes (24)(25)(26). The diabetic nephropathy and glucose metabolism abnormality in db mice are aggravated by a high protein content diet (21,22). In the present study, db mice were used to evaluate the effects of dietary protein and carbohydrate content on diabetic retinopathy.…”

“…The effect of dietary protein content diets (12-24% energy), which is the range in regular human diets (4, 8), on glucose levels and renal manifestations in db mice (19,20), an animal model for diabetes with leptin-receptor deficiency. In the experiments using db mice, a high-protein, low-carbohydrate diet increased blood glucose levels and exacerbated renal manifestations, compared with a low-protein, high-carbohydrate diet (21,22). The dietary protein content should be examined for its 265…”

Voluntary exercise under a food restriction condition decreases blood branched-chain amino acid levels, in addition to improvement of glucose and lipid metabolism, in db mice, animal model of type 2 diabetes

“…Biochemical parameters Blood (0.5 ml) was drawn from the heart with a syringe containing 0.2 mol/l EDTA (10 ll), and organs including the heart, liver, SM, and WAT were isolated [22]. The organs were rinsed in isotonic saline, weighed, and quickly frozen in liquid nitrogen.…”