Eight weeks of dietary overfeeding increases renal filtration rates in humans: implications for the pathogenesis of diabetic hyperfiltration

Abstract

Objective Diabetic nephropathy is characterized at its onset by glomerular hyperfiltration. Prospective studies in humans measuring filtration rates with weight gain are lacking. We investigated renal filtration following weight gain induced by overfeeding. Design Eight week of overfeeding (40 percent above energy requirements; 44 percent fat, 15 percent protein and 41 percent carbohydrate) as well as a six month follow-up after the overfeeding intervention. Subjects Thirty-five participants (age: 26.7 ± 5.3 yrs; BMI: 25.5 ± 2.2 kg/m2; 29m/6f). Measurements Creatinine clearance rate (Ccr) from 24-hour urine collection, estimated glomerular filtration rate (eGFR) from the modification of diet in renal disease (MDRD), insulin sensitivity/glucose disposal rate (GDR) by a euglycemic-hyperinsulinemic clamp, components from basic metabolic panels, and serum lipid panels Results Both eGFR and Ccr increased with overfeeding (p = 0.04) and serum lipids (all p < 0.05), along with a decrease in insulin sensitivity (p = 0.003). Fasting glucose concentration was not affected (p = 0.98), but the percent change in Ccr correlated positively with the change in GDR with overfeeding (r = 0.39, p = 0.02). Six months following overfeeding, serum glucose was maintained, and no evidence of urinary glucose was observed at any time point. Conclusions This data suggests that renal hyperfiltration may act as a mechanism to preserve insulin sensitivity through maintenance of systemic glucose homeostasis with caloric excess.

Differences in prevalence and management of chronic kidney disease among T2DM inpatients at the grassroots in Beijing and Taiyuan: a retrospective study

“…The food source was recorded in our study, but no detailed classification was supplied, so no distinctions between total red meat, processed meat, or plant protein were drawn. A high-fat diet, on the other hand, was frequently accompanied by a high-calorie intake, increasing LDL-C and TG levels and leading to an impairment of kidney function in just eight weeks [ 27 ]. Thus, the protective effects of a low-fat diet may indeed exist, and this causal relationship must be further investigated in the future.…”