Polydipsia

Abstract: Marked polydipsia was produced in all animals trained to press a bar for food pellets on a 1-minute variableinterval schedule. It is suggested that since this feeding arrangement produces a sustained, high fluid intake in the normal, unrestrained animal, it might serve as a useful tool in the study of renal function.

Abstract: D uring the past 2 years, Clinical Diabetes has published “Diabetes Foundation,” an eight-part series intended to explain and review facets of diabetes care for general physicians and physicians in training. The goal of the series has been to improve diabetes care for patients treated by such physicians because only a very small percentage of patients with diabetes have access to an endocrinologist. Although previous articles have focused on individual topics related to diabetes care and have reviewed available scientific data, this final article will focus on summarizing recommendations from the American Diabetes Association (ADA) and integrating them as a set of clinical practice guidelines. Information supporting the recommendations has appeared in the previous installments of “Diabetes Foundation” and from the ADA.1 Although there are always exceptions, it is likely that the majority of patients with diabetes or glucose abnormalities would benefit from implementation of many of these guidelines for prevention of diabetes itself and of the complications of diabetes and diabetes treatments. Patients who are experiencing symptoms of diabetes such as polyuria, polydipsia, or unexplained weight loss should be screened for diabetes, especially if they are obese or overweight (BMI > 25 kg/m2). Asymptomatic adult patients should be tested at any age if they are overweight or obese and have an additional risk factor for diabetes. Children who are overweight (BMI greater than the 85th percentile or weight > 120% of ideal for height) should be screened for type 2 diabetes if they have a family history of type 2 diabetes, are of an ethnic background predisposed to diabetes, have signs of insulin resistance such as acanthosis nigricans on physical examination, have a maternal history of diabetes or gestational diabetes mellitus (GDM), or have other conditions typically associated with type 2 diabetes. Such testing in children should …

Abstract: OBJECTIVE To determine whether dietary compounds targeting NFE2-related factor 2 (Nrf2) activation can be used to attenuate renal damage and preserve renal function during the course of streptozotocin (STZ)-induced diabetic nephropathy. RESEARCH DESIGN AND METHODS Diabetes was induced in Nrf2 +/+ and Nrf2 −/− mice by STZ injection. Sulforaphane (SF) or cinnamic aldehyde (CA) was administered 2 weeks after STZ injection and metabolic indices and renal structure and function were assessed (18 weeks). Markers of diabetes including blood glucose, insulin, polydipsia, polyuria, and weight loss were measured. Pathological alterations and oxidative damage in glomeruli were also determined. Changes in protein expression of the Nrf2 pathway, as well as transforming growth factor-β1 (TGF-β1), fibronectin (FN), collagen IV, and p21/WAF1Cip1 (p21) were analyzed. The molecular mechanisms of Nrf2-mediated protection were investigated in an in vitro model using human renal mesangial cells (HRMCs). RESULTS SF or CA significantly attenuated common metabolic disorder symptoms associated with diabetes in Nrf2 +/+ but not in Nrf2 −/− mice, indicating SF and CA function through specific activation of the Nrf2 pathway. Furthermore, SF or CA improved renal performance and minimized pathological alterations in the glomerulus of STZ-Nrf2 +/+ mice. Nrf2 activation reduced oxidative damage and suppressed the expression of TGF-β1, extracellular matrix proteins and p21 both in vivo and in HRMCs. In addition, Nrf2 activation reverted p21-mediated growth inhibition and hypertrophy of HRMCs under hyperglycemic conditions. CONCLUSIONS We provide experimental evidence indicating that dietary compounds targeting Nrf2 activation can be used therapeutically to improve metabolic disorder and relieve renal damage induced by diabetes.