Consumption of a high-fat diet does not potentiate the deleterious effects on lipid and protein levels and body development in rats subjected to maternal protein restriction.

Maternal undernutrition may cause injuries in several organs of the offspring, as well as lead to diseases in adulthood. Obesity and/or the consumption of a high-fat diet may also induce metabolic and cardiorespiratory diseases. We hypothesized that the consumption of a post-weaning high-fat diet would potentiate the deleterious effects of maternal protein undernutrition. This study evaluated the effects of the association of a low-protein diet during gestation and lactation with a post-weaning high-fat diet on the biochemical and ventilatory parameters of rats. Male Wistar rats from mothers who received a low-protein (9% of protein) or normoprotein diet during pregnancy and lactation received a high-fat (32% of total kilocalories from lipids) or a normal fat diet after weaning. Mass gain and somatic growth of the offspring were monitored. Also examined were biochemical chemical parameters and respiratory frequency, tidal volume (volume of air displaced in each normal respiratory cycle when extra effort is not applied), and pulmonary ventilation. Offspring from undernourished mothers presented lower birth weight (P = .0225), which remained until the end of lactation (P < .01). The rats that consumed high-fat diet and had been submitted to maternal undernutrition presented higher tidal volume when compared to the ones that consumed control diet at the 21st day of life (P Ë‚ .05). At 30 and 90 days, no further ventilatory changes were observed. Our data show that the consumption of a high-fat diet post-weaning did not seem to potentiate the changes induced by maternal undernutrition.

Protein restriction in early life increases intracellular calcium and insulin secretion, but does not alter expression of SNARE proteins during pregnancy.

NEW FINDINGS: What is the central question of this study? Does protein restriction in early life modify glucose-induced insulin secretion by altering [Ca2+ ]i and the expression of SNARE proteins in pancreatic islets from pregnant rats? What is the main finding and its importance? Protein restriction in early life increased the first phase of glucose-induced insulin secretion and [Ca2+ ]i without altering the expression of SNARE proteins during pregnancy. This finding contributes to our understanding of the mechanisms of altered insulin secretion and might provide new perspectives for the development of therapeutic tools for gestational diabetes. ABSTRACT: We investigated the kinetics of glucose-induced insulin secretion and their relationship with [Ca2+ ]i and the expression of protein from exocytotic machinery in islets from recovered pregnant and long-term protein-deficient pregnant rats. Isolated islets were evaluated from control-fed pregnant (CP), protein-deficient pregnant (DP), control-fed non-pregnant (CNP) and protein-deficient non-pregnant (DNP) female adult rats, and from protein-deficient pregnant (RP) and non-pregnant (RNP) rats that were recovered after weaning. The insulin responses to glucose during the first phase of secretion were higher in RP than in CP groups, and both were higher than in the DP group. Islets from RP rats displayed a rapid increase in insulin release (first phase), followed by a plateau that was maintained thereafter. The [Ca2+ ]i in islets from the protein-deficient groups was lower than in the control groups, and both were lower than in the RP and RNP groups. SNAP-25 was increased in islets from pregnant rats independently of their nutritional status, and the syntaxin-1A content was reduced in islets from the RP rats compared with the RNP rats. The VAMP2 content was similar among the groups. Thus, protein restriction during intrauterine life and lactation increased insulin secretion during pregnancy, attributable, in part, to increased [Ca2+ ]i , and independent of an alteration of expression of SNARE proteins.

A Multicomponent Neuronal Response Encodes the Larval Decision to Pupariate upon Amino Acid Starvation.

Organisms need to coordinate growth with development, particularly in the context of nutrient availability. Thus, multiple ways have evolved to survive extrinsic nutrient deprivation during development. In Drosophila, growth occurs during larval development. Larvae are thus critically dependent on nutritional inputs; but after critical weight, they pupariate even when starved. How nutrient availability is coupled to the internal metabolic state for the decision to pupariate needs better understanding. We had earlier identified glutamatergic interneurons in the ventral ganglion that regulate pupariation on a protein-deficient diet. Here we report that Drosophila third instar larvae (either sex) sense arginine to evaluate their nutrient environment using an amino acid transporter Slimfast. The glutamatergic interneurons integrate external protein availability with internal metabolic state through neuropeptide signals. IP3-mediated calcium release and store-operated calcium entry are essential in these glutamatergic neurons for such integration and alter neuronal function by reducing the expression of multiple ion channels.SIGNIFICANCE STATEMENT Coordinating growth with development, in the context of nutrient availability is a challenge for all organisms in nature. After attainment of "critical weight," insect larvae can pupariate, even in the absence of nutrition. Mechanism(s) that stimulate appropriate cellular responses and allow normal development on a nutritionally deficient diet remain to be understood. Here, we demonstrate that nutritional deprivation, in postcritical weight larvae, is sensed by special sensory neurons through an amino acid transporter that detects loss of environmental arginine. This information is integrated by glutamatergic interneurons with the internal metabolic state through neuropeptide signals. These glutamatergic interneurons require calcium-signaling-regulated expression of a host of neuronal channels to generate complex calcium signals essential for pupariation on a protein-deficient diet.

Safety and effectiveness of low-protein diet supplemented with ketoacids in diabetic patients with chronic kidney disease.

BACKGROUND: The impact of the low-protein diet on nutrition in CKD diabetics is uncertain. METHODS: The metabolic and nutritional effects of a low-protein (0.5-0.6 g/kg/d), normal-high energy (30-35 kcal/kg/d) diet supplemented with ketoacids (LPD-KA) were prospectively evaluated in CKD patients with (DM) and without (non-DM) diabetes mellitus. RESULTS: 197 patients on CKD stages 3-5 were enrolled. DM (n = 81) and non-DM (n = 116) were comparable for gender (Male 58 vs 55%), age (66 ± 9 vs 63 ± 18 years), renal function (eGFR 23 ± 13 vs 24 ± 13 mL/min). After 6-month, serum urea (DM: 131 ± 58 to 105 ± 49 mg/dl, p < 0.05; non-DM: 115 ± 52 to 88 ± 36, p < 0.05) and phosphate (DM: 4.5 ± 1.3 to 4.1 ± 1.2 mg/dl, p = 0.06; non-DM: 4.3 ± 1.0 to 3.7 ± 0.8, p < 0.05) declined. Fasting glucose decreased in DM (126 ± 52 to 103 ± 29 mg/dl, p < 0.05) without insulin dose increase. These effects were preserved after 3-year. Serum albumin did not change after 6 months (DM: 3.7 ± 0.6 to 3.8 ± 0.4 mg/dl; non-DM: 4.0 ± 0.6 to 4.0 ± 0.4) and in the long-term. Body weight (BW) declined after the diet start (DM: 68.9 ± 14.3 to 65.1 ± 12.1 kg, p < 0.05; non-DM: 66.6 ± 15.1 to 64.1 ± 15.1, p < 0.05) and was stable at 6 months and 3 years. Muscle strength at baseline was reduced in all patients and remained stable during the diet period. Changes of nutritional markers during the study were similar among groups and diabetes was not associated to any nutritional change at the multivariate analysis. As attain wasting, lower BMI (< 23 kg/m2) and albumin (< 3.8 g/dl) levels were present in 1/3 patients at start and along 3 years, cholesterol never dropped below the lower threshold (< 100 mg/dl) and poorer FM (< 10%) was less than 10% during the study in both groups. CONCLUSIONS: In diabetic CKD patients a low-protein diet supplemented with ketoacids improves uremia and diabetes, causes sudden decline of body weight which remains stable over time and has not a negative effect on wasting and muscle mass and fitness. In diabetic CKD patients the LPD-KA is safe and the nutritional impact is the same as in non-diabetics CKD.

Hitting a triple in the non-alcoholic fatty liver disease field: sucrose intake in adulthood increases fat content in the female but not in the male rat offspring of dams fed a gestational low-protein diet.

The excessive consumption of carbohydrates is related to non-alcoholic fatty liver disease (NAFLD) in infants and adults. The effect of combining maternal malnutrition and a high carbohydrate intake on the development of NAFLD in adulthood remains unknown. We therefore hypothesized that consumption of 5% sucrose by the offspring of dams fed a low-protein diet during pregnancy promotes liver fat accumulation and oxidative damage differently in females and males. To test this, 12-month-old female and male offspring of mothers fed a Control (C) or low-protein diet (Restricted, R) were provided with either tap water or 5% sucrose for a period of 10 weeks. Livers were excised to measure the fat content and 3-nitrotyrosine (3-NTyr) immunostaining; serum samples were also obtained to measure the concentration of malondialdehyde (MDA). Data were analyzed using a non-repeated measures three-way analysis of variance to determine significant differences (P<0.05) regarding to the interaction among maternal diet, sucrose consumption and sex. Results showed that the liver fat content of females from R mothers was higher than that of their male counterpart. Hepatic 3-NTyr immunostaining and serum MDA concentrations were not affected by the interaction involving maternal diet, sucrose consumption and sex. Otherwise, liver fat content was correlated with the hepatic 3-NTyr immunostaining and serum MDA concentrations only in females. Thus, sucrose intake in adulthood increases fat content in the female but not in the male rat offspring of dams fed with a low-protein diet during pregnancy. This research emphasizes the importance of a balanced diet during pregnancy and the influence of the diet on the adult offspring.

Long-term effect of a chronic low-protein multideficient diet on the heart: Hypertension and heart failure in chronically malnourished young adult rats.

BACKGROUND: We investigated whether a chronic low-protein multideficient diet (BRD) from weaning turns on cardiovascular adaptive responses that could culminate in hypertension and heart failure. METHODS AND RESULTS: Systolic pressure (SP) and heart rate (HR) were determined in CTRL (normal diet) and BRD rats. Plasma albumin, plasma urea and urinary urea excretion decreased in BRD rats. In this group, echocardiography and the Langendorff technique showed: (i) increased HR and hypertension; (ii) decreased LVDP, dP/dtmax, dP/dtmin, cardiac output, ejection fraction, stroke volume and left ventricular diameter. BRD rats were less sensitive to isoproterenol (ISO) in LVDP and dP/dtmax, with unchanged dP/dtmin; Pressure-volume relationships indicated left-oriented shifts in LVDP, SP and DP, and decreased capacitance compared to CTRL. BRD rats had higher cardiac and lung indexes, accompanied by muscle atrophy and recent ventricular-infarcted areas, higher ventricular ß1-AR content, and decreased ß2-AR and α1-AR. Propranolol treatment gave similar ISO responses in both groups, disappearance of the infarcted regions and, except for ß2-AR, recovery of normal receptor expression. BRD rats had intense stimulation of plasma membrane Ca2+-ATPase (PMCA) activity, with increased Ca2+ affinity and inhibition of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA). Ventricular phospholamban increased and Na+/Ca2+ exchanger decreased. PMCA activity correlated with an increase in its PKC-mediated phosphorylation, overlying a decrease in PKA-catalyzed phosphorylation. Propranolol normalized PKC and PKA activities with recovery of PMCA but not SERCA. CONCLUSION: BRD triggers sympathetic exacerbation and dysfunction in Ca2+ handling, accompanied by early onset of hypertension and left ventricle congestive heart failure.

Vegan-vegetarian low-protein supplemented diets in pregnant CKD patients: fifteen years of experience.

BACKGROUND: Pregnancy in women with advanced CKD becoming increasingly common. However, experience with low-protein diets in CKD patients in pregnancy is still limited. Aim of this study is to review the results obtained over the last 15 years with moderately restricted low-protein diets in pregnant CKD women (combining: CKD stages 3-5, proteinuria: nephrotic at any time, or > =1 g/24 at start or referral; nephrotic in previous pregnancy). CKD patients on unrestricted diets were employed for comparison. STUDY PERIOD: January, 2000 to September, 2015: 36 on-diet pregnancies (31 singleton deliveries, 3 twin deliveries, 1 pregnancy termination, 1 miscarriage); 47 controls (42 singleton deliveries, 5 miscarriages). The diet is basically vegan; since occasional milk and yoghurt are allowed, we defined it vegan-vegetarian; protein intake (0.6-0.8 g/Kg/day), keto-acid supplementation, protein-unrestricted meals (1-3/week) are prescribed according to CKD stage and nutritional status. Statistical analysis was performed as implemented on SPSS. RESULTS: Patients and controls were similar (p: ns) at baseline with regard to age (33 vs 33.5), referral week (7 vs 9), kidney function (CKD 3-5: 48.4 % vs 64.3 %); prevalence of hypertension (51.6 % vs 40.5 %) and proteinuria >3 g/24 h (16.1 % vs 12.2 %). There were more diabetic nephropathies in on-diet patients (on diet: 31.0 % vs controls 5.3 %; p 0.007 (Fisher)) while lupus nephropathies were non-significantly higher in controls (on diet: 10.3 % vs controls 23.7 %; p 0.28 (Fisher)). The incidence of preterm delivery was similar (<37 weeks: on-diet singletons 77.4 %; controls: 71.4 %). The incidence of other adverse pregnancy related outcomes was non-significantly lower in on-diet patients (early preterm delivery: on diet: 32.3 % vs controls 35.7 %; birth-weight = <1.500 g: on diet: 9.7 % vs controls 23.8 %). None of the singletons in the on-diet series died, while two perinatal deaths occurred among the controls (p = 0.505). The incidence of small for gestational age (SGA <10th centile) and/or extremely preterm babies (<28th week) was significantly lower in singletons from on-diet mothers than in controls (on diet: 12.9 % vs controls: 33.3 %; p: 0.04 (Fisher)). CONCLUSION: Moderate protein restriction in the context of a vegan-vegetarian supplemented diet is confirmed as a safe option in the management of pregnant CKD patients.

Dietary management of feline chronic renal failure: where are we now? In what direction are we headed?

Dietary modification is of primary importance in managing cats with chronic renal failure. Diets designed for cats with chronic renal failure are typically formulated to be pH neutral and contain reduced quantities of protein, phosphorus and sodium and an increased quantity of potassium. These changes in diet formulation are designed to ameliorate clinical signs of renal failure by adapting dietary intakes to meet the limited ability of failing kidneys to adapt to the normal range of dietary intakes. Important recent clinical trials support the therapeutic value of dietary therapy in cats with chronic renal failure.