Low-protein Group Research Articles

Effect of protein intake beyond habitual intakes following resistance training on cardiometabolic risk disease parameters in pre-conditioned older women.

The aim of this study was to analyze the effects of higher protein (HP) intake associated with resistance training (RT) on parameters of cardiometabolic risk disease (CMR). A randomized, double-blind and placebo-controlled design was conducted. Thirty-two pre-conditioned older women were randomized in two groups to receive 35 g of protein (high protein group - HP) or 35 g of placebo (low protein group - LP) after training sessions. The RT program was carried out over 12 weeks, 3 days per week and 3 sets of 8-12 repetitions. Body composition (whole-body dual-energy X-ray absorptiometry), blood samples, anthropometric measurements and dietary intake were performed at pre- and post-intervention. There was a significant group-by-time interaction (P < 0.05) for lean soft tissue (LST), total cholesterol/high density lipoprotein ratio (TC/HDL) and volume of load (VL), in which HP group presented greater improvements when compared to LP group (LST: +3.8% vs +2.0%; TC/HDL: -11.8% vs -2.9%; VL: 45.4% vs 35.4%). A time effect was found for HDL, LDL, Triglycerides (TGC), total cholesterol (TC), low density lipoprotein/HDL ratio (LDL/HDL) and C-reactive protein (CRP) (HDL: +6.7% vs +6.3%; LDL: -6.8% vs +0.9%; TGC: -2.0% vs -1.2%; TC: -2.8% vs +0.5%; LDL/HDL: -11.5 vs -6.9%; CRP: -8.6% vs -11.5%) in which both groups improved their scores without statistical differences between them. No effect was found for waist circumference. Increased dietary protein intake, achieved by whey protein supplementation, when associated with RT promotes greater gains on LST and VL, and a reduction on TC/HDL ratio in pre-conditioned older women.

Effect of increased enteral protein intake on plasma and urinary urea concentrations in preterm infants born at

BackgroundFeeding breast milk is associated with reduced morbidity and mortality, as well as improved neurodevelopmental outcome but does not meet the high nutritional requirements of preterm infants. Both plasma and urinary urea concentrations represent amino acid oxidation and low concentrations may indicate insufficient protein supply.This study assesses the effect of different levels of enteral protein on plasma and urinary urea concentrations and determines if the urinary urea-creatinine ratio provides reliable information about the protein status of preterm infants.MethodsSixty preterm infants (birthweight < 1500 g; gestational age < 32 weeks) were enrolled in a randomized controlled trial and assigned to either a lower-protein group (median protein intake 3.7 g/kg/d) or a higher-protein group (median protein intake 4,3 g/kg/d). Half the patients in the higher-protein group received standardized supplementation with a supplement adding 1.8 g protein/100 ml milk, the other half received individual supplementation depending on the respective mother’s milk macronutrient content. Plasma urea concentration was determined in two scheduled blood samples (BS1; BS2); urinary urea and creatinine concentrations in weekly spot urine samples.ResultsThe higher-protein group showed higher plasma urea concentrations in both BS1 and BS2 and a higher urinary urea-creatinine-ratio in week 3 and 5–7 compared to the lower-protein group. In addition, a highly positive correlation between plasma urea concentrations and the urinary urea-creatinine-ratio (p < 0.0001) and between actual protein intake and plasma urea concentrations and the urinary urea-creatinine-ratio (both p < 0.0001) was shown.ConclusionsThe urinary urea-creatinine-ratio, just like plasma urea concentrations, may help to estimate actual protein supply, absorption and oxidation in preterm infants and, additionally, can be determined non-invasively. Further investigations are needed to determine reliable cut-off values of urinary urea concentrations to ensure appropriate protein intake.Trial registrationClinicaltrials.gov; NCT01773902 registered 15 January 2013, retrospectively registered.

Differential mGluR5 expression in response to the same stress causes individually adapted hippocampal network activity

Individual differences in stress vulnerability and resilience have been observed even within a single cohort of inbred rats or mice. Stress phenotypes are typically quantified as changes in the behavior of experimental animals, which is the outcome of altered electrical activity of the brain network. Although mGluR5 is associated with individual vulnerability to stress and can act as a sensitive biomarker of stress adaptation, our understanding of mGluR5-dependent modifications to neural network activities in vivo remains limited. Here, we examined individual rats for changes in hippocampal mGluR5 expression induced by restraint stress and found that these changes cause accompanying changes in hippocampal electroencephalography (EEG) activity. We found six days of restraint stress caused variable changes in hippocampal mGluR5 expression, ranging from 20.9% to 210.7% of the control group. The low mGluR5 protein group (LE) showed increased methylation of the mGluR5 CpG island, reduced mGluR5 mRNA levels, and unaltered basal EEG theta spectral power between stress day 1 and 6. In contrast, the high mGluR5 protein group (HE) showed reduced methylation of CpG sites, increased mGluR5 mRNA expression, and reduced basal theta spectral power on stress day 6. We also found that injection of lentiviruses expressing mGluR5-specific shRNAs into the hippocampus rescued this reduction in baseline theta power in HE rats. These data suggest a causal relationship between individual differences in the changes in hippocampal mGluR5 expression induced by repetitive restraint stress and the accompanying changes in ensemble neural activity in the hippocampus.

Abstract 821: Loss and retention of mutations in cell culture model systems

Abstract Although relevant, the genomic and proteomic alterations between original tumor tissue and newly established cell lines are frequently uncharacterized. In developing a novel cell model (Powder) of high grade serous carcinoma (HGSC), we followed the status of clinically relevant biomarkers to identify changes taking place between the tissue and cultured cell population. Understanding these changes enables proper utilization of new models and continued model optimization. Using a validated panel, we analyzed 592 genes in the Powder cell model and tumor from which it was derived, detecting several classes of genomic alterations. This included point mutations, indels, copy number variations, fusions, and variant transcripts. p53 mutation status of Powder was matched to a panel of previously reported HGSC cell lines. We further subdivided the panel by p53 protein expression level by reanalyzing previously published reverse phase protein array (RPPA) data. Significance of differential expression between groups was determined with a Welch's t-test. A majority (14/21 or 67%) of the mutations detected in the HGSC tumor were conserved in the Powder cell model. Two additional mutations, undetected in the tumor, were found in the cell model. The tumor exhibited moderate to strong diffuse positive p53 immunostaining, and p53 mutations were measured in 79% of alleles. While the p53 mutation did not carry to the cell model, the cells were positive for CK7 and PAX8, consistent with ovarian cancer cells. In the panel of HGSC cell lines, we examined p53 mutation status and protein level, identifying 3 groups: (1) p53-mut/high protein, (2) p53-mut/low protein and (3) p53-WT/low protein. Powder identified with the p53-WT/low protein group. Previous work identifies the p53-WT/low protein group of cell models as part of a larger set of novel ovarian cell models with a stem-like molecular profile and higher drug resistance. Analysis of differential protein expression revealed upregulation in the p53 low protein group of both normal cell cycle genes and of notable cancer-related proteins. This included p21 and BAD, which are upregulated in cells with functional p53, eIF4E, a candidate cancer therapeutic target, and BOP1, which is disregulated in multiple solid cancers, including ovarian. These results underscore the need for further characterization of the Powder cell model to clarify its applications to specific research questions. Continued examination of Powder and other p53-WT cell models derived from HGSC tumors may uncover independent pathways driving disease. Additionally, understanding which mutations are underrepresented by cell models is necessary for ongoing methods development. Citation Format: Pamela S. Shaw, Rick Nicoletti, Naghmeh Salimi, Helen L. Yang, Abigail E. Witt, Agoston T. Agoston, Elin S. Agoston. Loss and retention of mutations in cell culture model systems [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 821. doi:10.1158/1538-7445.AM2017-821

Influence of protein deficient diet, vitamin B[sub]2[/sub] supplementation and physical training on serum composition of polyunsaturated fatty acids (PUFAs) in rats.

[b]Introduction[/b]. Prolonged shortages of protein in the diet significantly alter the composition and content of polyunsaturated fatty acids (PUFA) in tissues and body fluids. One of nutritional factors which may reduce negative effects of protein malnutrition might be vitamin B[sub]2[/sub] due to its influence on lipids metabolism. [b]Objective. [/b]The aim of the study was to investigate the influence of low protein (LP) diet enriched with vitamin B[sub]2[/sub] on the content and composition of PUFA in the blood serum of rats treated with dosed physical exercise. [b]Materials and method. [/b]The experiment was carried out for 3 months on 72 growing male Wistar rats divided into 5 groups. Animals were fed ad libitum on a diet with an energy value of 350 kcal/100 g, in which 4.5% of the energy was provided by protein. In the control diet, 20% of the energy was provided by protein. Two groups were fed the diet enriched with vitamin B2. The two groups of tested animals were trained for 5 days a week. [b]Results.[/b] LP diet caused a decrease in α-linolenic acid (ALA) after 30 days, and a decrease in docosahexaenoic acid (DHA) after 60 days of experiment, compared with rats fed the control diet. After 60 and 90 days of the experiment, a significant decrease was noted in arachidonic acid (AA) in serum of trained rats, compared with sedentary rats fed the LP diet. Physical activity increased LA (mainly on day 30), EPA (on day 90) and reduced AA content (on day 90) in serum of rats fed the LP diet. B2 supplementation in the trained LP group did not change the EPA and AA dependence; however, there was a decrease in LA content in comparison to the non-supplemented trained group. [b]Conclusions. [/b] Results of this study suggest that all investigated factors (protein deficiency, physical exercise and supplementation of vitamin B2) have significant impact on PUFA composition of serum in rats.

Maternal protein restriction depresses the duodenal expression of iron transporters and serum iron level in male weaning piglets.

To investigate the effects of maternal dietary protein restriction on offspring Fe metabolism, twenty-four second-parity Landrace×Yorkshire sows were randomly allocated to standard-protein (SP) and low-protein (LP) groups. The SP sows were fed diets containing 15 and 18 % crude protein throughout pregnancy and lactation, respectively, whereas the LP sows were subjected to 50 % dietary protein restriction. Offspring birth weight was not affected, but the body weight at weaning (P=0·06) and average daily gain (P=0·01) of the female piglets were significantly decreased. Serum Fe level in the LP piglets was markedly decreased at weaning, especially in males (P=0·03). Serum ferritin level (P=0·08) tended to be lower, yet serum transferrin was greatly higher (P=0·01) in male weaning piglets of the LP group. Duodenal expression of the divalent metal transporter 1 (DMT1) and ferroportin (FPN) was surprisingly reduced (P<0·05) at the level of protein, but not at the mRNA level, in male weaning piglets of the LP group. Male weaning piglets born to the LP sows exhibited higher hepatic hepcidin levels (P=0·09), lower hepatic expression of transferrin (P<0·01) and transferrin receptor 1 (P<0·05) at the level of mRNA. However, no significant differences were observed for hepatic Fe storage, ferritin, transferrin and transferrin receptor 1 protein expression in male weaning piglets of the two groups. These results indicate that maternal protein restriction during pregnancy and lactation influences growth of female offspring at weaning, reduces duodenal expression of Fe transporters (DMT1 and FPN) and decreases serum Fe level in male weaning piglets.

Effects of Diet Intervention on Body Composition in the Elderly with Chronic Kidney Disease.

Objective: It has been uncertain that low protein diet for patients with chronic kidney disease (CKD) may predispose to malnutrition. The study aimed to investigate the effects of low protein diet on body composition of CKD patients and analyze the influence of age.Methods: Patients with glomerular filtration rate less than 45 mL/min/1.73m2 including 103 elderly (70.7 ± 6.9 years old) and 56 non-elderly (49.8 ± 9.1 years old) CKD patients were enrolled. All patients were educated by dietitians to take low protein diet and were followed up regularly every three months. Their demographic data, underlying disease and body mass index (BMI) were reviewed and recorded. Results of body composition measurement and laboratory tests were collected every three months for one year.Results: At baseline, the distribution of body composition was similar in non-elderly patients between non-low and low protein groups. In the elderly, patients in low protein group had higher fat and lower muscle percentage. In one-year follow-up, non-elderly patients did not present significant changes in their BMI, serum albumin level and body compositions in both protein groups. Non-low protein group in elderly patients had significant decrease in BMI and estimated glomerular filtration rate (eGFR) after 12 months (both p< 0.05). Determination in body composition showed decrease in fat and increase in muscle component. In low protein group, their BMI was decreased and eGFR was not influenced. Fat component was decreased and muscle percentage was increased in one-year follow-up.Conclusions: In elderly CKD patients, low protein diet maintained good nutritional status and muscle mass was preserved.

Gestational Protein Restriction in Wistar Rats; Effect of Taurine Supplementation on Properties of Newborn Skeletal Muscle.

Taurine ameliorates changes occurring in newborn skeletal muscle as a result of gestational protein restriction in C57BL/6 mice, but taurine supplementation effects may be exaggerated in C57BL/6 mice due to their inherent excessive taurinuria.We examined if maternal taurine supplementation could ameliorate changes in gene expression levels, properties of mitochondria, myogenesis, and nutrient transport and sensing, in male newborn skeletal muscle caused by a maternal low protein (LP) diet in Wistar rats.LP diet resulted in an 11% non-significant decrease in birth weight, which was not rescued by taurine supplementation (LP-Tau). LP-Tau offspring had significantly lower birth weight compared to controls. Gene expression profiling revealed 895 significantly changed genes, mainly an LP-induced down-regulation of genes involved in protein translation. Taurine fully or partially rescued 32% of these changes, but with no distinct pattern as to which genes were rescued.Skeletal muscle taurine content in LP-Tau offspring was increased, but no changes in mRNA levels of the taurine synthesis pathway were observed. Taurine transporter mRNA levels, but not protein levels, were increased by LP diet.Nutrient sensing signaling pathways were largely unaffected in LP or LP-Tau groups, although taurine supplementation caused a decrease in total Akt and AMPK protein levels. PAT4 amino acid transporter mRNA was increased by LP, and normalized by taurine supplementation.In conclusion, gestational protein restriction in rats decreased genes involved in protein translation in newborn skeletal muscle and led to changes in nutrient transporters. Taurine partly rescued these changes, hence underscoring the importance of taurine in development.

Evaluation of Protein Levels in Diets for Salema Porgy (&amp;lt;i&amp;gt;Sarpa salpa&amp;lt;/i&amp;gt;) Juveniles, a New Candidate Species for the Mediterranean Aquaculture

In the present study, the effects of different dietary protein levels on salema porgy, Sarpa salpa (Linnaeus, 1758) juveniles were investigated. Six iso-caloric (20 kJ/g diet) diets with increasing protein levels (30, 37, 40, 47, 50, and 57%) were formulated. Each test diet was randomly fed to triplicate groups of 13 juvenile fish (initial mean weight 19.28±0.13 g) to satiety over 90 days. Growth performance and feed utilization were best with low dietary protein levels of 30 and 37%, but decreased with diets containing protein levels over 40%. Ammonia nitrogen excretion showed an increasing trend as dietary protein levels gradually increased, whereas retention rates of ammonia nitrogen per intake were highest in the low protein groups of 30 or 37%. The analyses of specific growth rate by broken-line regression indicated that the optimal dietary level of protein for salema porgy juvenile were 33.6% under the conditions applied in this study. As a result, S. salpa demonstrated better growth with low protein diets, showing that this marine fish could be a promising candidate for a sustainable and environment friendly aquaculture industry.

Evaluation of behaviour in stabled draught horse foals fed diets with two protein levels

The present work is aimed at evaluating the behaviour of Italian Heavy Draught Horse (IHDH) foals reared in semi-covered stables and fed two isoenergetic total mixed rations with different dietary protein levels (13.2% and 10.6% of CP on dry matter). The study was prompted by the restrictions for nitrate emissions in farms of the European Nitrate Directive. One suggested solution is to reduce dietary protein while maintaining normal performance and welfare, but there is a lack of literature in studies of horses. The behaviours of 20 foals of 437±60 kg of BW, aged 379±37 days and stabled in four pens by sex (S) and diet (D) were video recorded and analysed to build a suitable ethogram including 18 behaviours in six categories: ingestion, resting, maintenance, movement, social activities, other. The percentage of the daily time spent in each behavioural category and single behaviours was analysed via a single traits GLM including S, D and their interaction. Daily activity was consistent with existing literature: foals spent about 33% of the day in ingestion activities and 41% in resting, whereas social interactions constituted 8% of the time and individual maintenance <2%. Concerning diet, foals fed high protein spent more time in movement (19.62±0.73% of day v. 10.45±0.73% in low-protein (LP) foals; P⩽0.001), whereas the LP group increased resting (43.42±1.12% v. 38.02±1.12%; P⩽0.001). No stereotypies were found, and daily activity followed the typical values for draught breeds for foals in both dietary groups, a result that suggests the maintenance of well-being after dietary protein reduction. This result, together with the findings of a companion study showing no changes in growth performances of foals, showed that a reduction of CP in foal diet is reconcilable with the maintenance of performance and welfare.

Effect of Increased Enteral Protein Intake on Growth in Human Milk–Fed Preterm Infants

Protein, supplied in currently available commercial fortifiers, may be inadequate to meet the requirements of very preterm infants; in addition, intraindividual and interindividual variability of human milk protein and energy content potentially contribute to unsatisfactory early postnatal growth. To determine effects on growth of different levels of enteral protein supplementation in predominantly human milk-fed preterm infants. This randomized clinical and partially blinded single-center trial was conducted in a neonatal tertiary referral center in Germany. Sixty preterm infants (gestation <32 weeks and weight <1500 g at birth) were recruited from October 2012 to October 2014 and included 35% of 173 eligible infants. Median (interquartile range [IQR]) gestational age at birth was 29.9 (28.7-31.2) weeks. All analyses were conducted in an intention-to-treat population. Infants were randomly assigned to either a lower-protein (adding 1 g of bovine protein/100 mL of breast milk through a commercial human milk fortifier; n = 30) or a higher-protein group at a median (IQR) postnatal age of 7 (6-8) days. The higher-protein group (n = 30) received either standardized higher-protein supplementation (study fortifier adding 1.8 g of bovine protein/100 mL of breast milk [n = 15]) or individualized high-protein supplementation based on protein and fat content of administered breast milk (n = 15). Study interventions were continued for a median (IQR) of 41 (30-57) days and until definite discharge planning. Primary outcome was weight gain (g/kg/d) from birth to the end of intervention. Sixty preterm infants (gestation <32 weeks and weight <1500 g at birth), 33 girls, were recruited from October 2012 to October 2014 and included 35% of 173 eligible infants. Median (IQR) gestational age at birth was 29.9 (28.7-31.2) weeks. Demographic characteristics and hospital courses were similar in both groups, and birth weights ranged from 580 to 1495 g in the lower-protein group and 490 to 1470 g in the higher-protein group. Weight gain was similar in the lower- and higher-protein groups: mean (95% CI), 16.3 g/kg/d (15.4-17.1 g/kg/d) in the lower-protein group vs 16.0 g/kg/d (15.1-16.9 g/kg/d) in the higher-protein group) (P = .70), despite an increase in actual protein intake by 0.6 g/kg/d (0.4-0.7 g/kg/d) (P < .001). Head circumference and lower leg longitudinal growth were also similar, as was the proportion of cumulative total enteral feeding volume provided as breast milk: median (IQR) proportion of breast milk, 92% (79%-98%) in the lower-protein group vs 94% (62%-99%) in the higher-protein group (P = .89). An increase in protein intake by 0.6 g/kg/d to a mean intake of 4.3 g/kg/d did not further enhance growth of very preterm infants with a median birth weight of 1200 g, who achieved near-fetal growth rates. This might point to a ceiling effect for enteral protein intake with respect to its influence on growth. clinicaltrials.gov Identifier: NCT01773902.

Effects of perinatal protein malnutrition and fenfluramine action on food intake and neuronal activation in the hypothalamus and raphe nuclei of neonate rats

In neonatal rats, hunger and satiety responses occur particularly via dehydration and gastric distention, respectively. The control of food intake in newborns is yet to be fully consolidated, particularly with respect to the participation of the hypothalamic nuclei and their relationship with the serotonergic pathway. Moreover, it is unclear how the environmental stressors in early life, like undernutrition, interfere in these events. Therefore, this study examined the serotonin-system's impact on food intake in rat neonates at postnatal day (P) 10 and P18 and the manner in which protein undernutrition during pregnancy and lactation interferes in this behavior. To accomplish this, Wistar rats were used, nutritionally manipulated by a diet having two protein levels, (8% and 17%) during pregnancy and lactation, to form the Control (n=10) and Low protein groups (n=10). At 10 and 18 postnatal days pups received an acute dose of fenfluramine (3mg/kg) or saline (0.9% NaCl) and subjected to milk consumption testing and then perfused to obtain the brains for the analysis of cell activation of the immunoreactive c-Fos in the hypothalamic and raphe nuclei. At 10days a reduction in weight gain was observed in both groups. On comparison of the neuronal activation for the paraventricular nucleus, an increased activation in response to fenfluramine was observed. At 18days, the weight gain percentage differed between the groups according to the nutritional manipulation, in which the control animals had no significant change while the undernourished presented increased weight gain with the use of fenfluramine. The marking of c-Fos in response to fenfluramine in the hypothalamic and raphe nuclei revealed, an especially lower activation of the PVN, MnR and DR compared intra-group. However when evaluating the effect of undernutrition, marking activation was observed to increase in all the nuclei analyzed, in the hypothalamus and raphe. Data from this study indicate that the action of serotonin via food intake in the neonates may have been delayed by early protein undernutrition.

Effects of maternal low-protein diet on parameters of locomotor activity in a rat model of cerebral palsy

Children with cerebral palsy have feeding difficulties that can contribute to undernutrition. The aim of this study was to investigate the effect of early undernutrition on locomotor activity and the expression of the myofibrillar protein MuRF-1 in an experimental model of cerebral palsy (CP). In order to achieve this aim, pregnant rats were divided into two groups according to the diet provided: Normal Protein (NP, n=9) and Low Protein (LP, n=12) groups. After birth, the pups were divided into four groups: Normal Protein Sham (NPS, n=16), Normal Protein Cerebral Palsy (NPCP, n=21), Low Protein Sham (LPS, n=20) and Low Protein Cerebral Palsy (LPCP, n=18) groups. The experimental cerebral palsy protocol consisted of two episodes of anoxia at birth and during the first days of life. Each day, nitrogen flow was used (9l/min during 12min). After nitrogen exposure, sensorimotor restriction was performed 16h per day, from the 2nd to the 28th postnatal day (PND). Locomotor activity was evaluated at 8th, 14th, 17th, 21th and 28th PND. At PND 29, soleus muscles were collected to analyse myofibrillar protein MuRF-1. Our results show that CP animals decreased body weight (p<0.001), which were associated with alterations of various parameters of locomotor activity (p<0.05), compared to their control. Undernourished animals also showed a decrease (p<0.05) in body weight and locomotor activity parameters. Moreover, CP decreased MuRF-1 levels in nourished rats (p=0.015) but not in undernourished rats. In summary, perinatal undernutrition exacerbated the negative effects of cerebral palsy on locomotor activity and muscle atrophy, but it appears not be mediated by changes in MuRF-1 levels.

Asupan protein, kalsium dan fosfor pada anak stunting dan tidak stunting usia 24-59 bulan

Background: Indonesia is one of developing country which still facing a serious problem concerning stunting. Causes of stunting is a complex things, one of the cause is protein intake which is have effect on the level plasma insulin growth factor I (IGF-I), protein bone matrix and growth factor, also calcium and phosphorus that has an important role in bone formation. One of the province in Indonesia which has stunting prevalence above level of National prevalence is West Borneo. Pontianak as the capital city of West Borneo is still facing serious problem concerning stunting and the low level of food security.Objective: Analyze protein, calcium and phosphorus intake of stunting and non stunting children aged 24-49 months in Pontianak.Method: The study was an analytical observational with cross sectional design. Samples of the study were children aged 24-59 months in the districts of East Pontianak and North Pontianak, West Borneo, as much as 90 samples have been chosen by using simple random sampling technique. The research was conducted from July - August 2015. Statistical analysis was performed by using chi square and t-test.Results: Protein, calcium and phosphorus intake are lower to the stunting compare to non stunting children (p&lt;0,05). Stunting prevalence of lower protein group is higher 1,87 times than adequate protein intake group. Stunting prevalence of low calcium intake group is higher 3,625 times than adequate calcium intake group. Moreover, the stunting prevalence of low phosphor intake group is higher 2,29 times than adequate phosphor intake group.Conclusion: Protein, calcium and phosphor intake significant lower to the stunting compare to non stunting children aged 24- 59 months in Pontianak.

Association of early protein intake and pre-peritoneal fat at five years of age: Follow-up of a randomized clinical trial

Background and aimsThe double-blind randomized European Childhood Obesity Project (CHOP) demonstrated that reduced protein content in infant formula leads to a lower body mass index (BMI) up to six years of age. Here we aimed at assessing pre-peritoneal fat, a marker of visceral fat, in children participating in the CHOP trial. Methods and resultsHealthy term formula-fed infants in five European countries were randomized either to higher (n = 550) or lower (n = 540) protein formulas in the first year of life. Infants who were exclusively breastfed for at least three months (n = 588) were enrolled as an observational (non randomized) group. At age 5 years, subcutaneous fat (SC) and pre-peritoneal fat (PP) were measured by ultrasound in a subgroup of 275 children. The PP fat layer was thicker in the higher compared to the lower protein group (adjusted estimated difference: 0.058 cm, 95%CI 0.002; 0.115; p = 0.043), while SC fat was not different. Girls showed a thicker SC fat layer than boys. ConclusionsHigher protein intake in formula-fed infants appears to enhance pre-peritoneal fat tissue accumulation at the age of 5 years, but not of subcutaneous fat, which may trigger adverse metabolic and health consequences.

Effects of a higher vs. lower protein diet on weight loss in teenagers: Results from a randomized controlled trial

ObjectiveTo provide pilot data on weight loss efficacy in overweight and obese adolescents during isocaloric lower vs higher protein weight loss diets utilizing the U.S. Department of Agriculture (USDA) MyPlate nutrition guide.MethodsThirty two, 12–17 year old adolescents with body mass index ≥ 85th percentile were recruited for a 12‐week free‐living weight loss intervention. Participants were randomized to either a lower protein group with 15% of energy as protein and 60% of energy from carbohydrate or a higher protein group with 30% of energy as protein and 45% of energy from carbohydrate. Both diets restricted energy intake by 25%. Dietary counseling was based on the USDA MyPlate guidelines. The first intervention session was individual followed by 6 (biweekly) group sessions. Participants had anthropometric measurements and performed retrospective visual analogue scale (VAS) appetite ratings at baseline and week 12.ResultsParticipants were 75 % female and 62.5 % black. The baseline mean (± SD) age, body weight, and BMI z‐score were 14.3 ± 1.5 y, 96.0 ± 21.9 kg, and 2.21 ± 0.48, respectively. The lower protein group reduced BMI z‐score compared to the higher protein group (0.18 ± 0.16 vs. 0.05 ± 0.09; p&lt;0.05). No other group differences were found but fullness tended to increase in the higher protein group (0.5 ± 20.5 vs. 14.9 ± 15.2; p=0.08). Participants lost 3.1 ± 2.0 kg vs. 1.5 ± 4.2 kg body weight and 2.8 ± 2.4 % vs. 3.0 ± 5.2 % body fat in the lower vs. higher protein groups, respectively. The lower protein group change from baseline BMI z‐score, body weight, and body fat were reduced (p≤0.002) but the higher protein group change from baseline values were not different from baseline. Exploratory analyses, with the protein groups combined, indicated that overweight adolescents reduced BMI z‐score 0.38 ± 0.12 compared to 0.07 ± 0.08 in the obese subgroup (p&lt;0.01).ConclusionsParticipants in the higher protein group tended to increase fullness, but this did not translate to greater weight loss. Higher dietary protein intake should not be recommended for weight loss in group based interventions in this study population. An adolescent intervention based on the USDA MyPlate guidelines is efficacious for weight loss in adolescents.Support or Funding InformationNIH U54 GM104940 and NIH P30 DK072476

Maternal protein restriction during gestation impairs female offspring pancreas development in the rat

A maternal low-protein (LP) diet programs fetal pancreatic islet β-cell development and function and predisposes offspring to metabolic dysfunction later in life. We hypothesized that maternal protein restriction during pregnancy differentially alters β- and α-cell populations in offspring by modifying islet ontogeny and function throughout life. We aimed to investigate the effect of an LP maternal diet on pancreatic islet morphology and cellular composition in female offspring on postnatal days (PNDs) 7, 14, 21, 36, and 110. Mothers were divided into 2 groups: during pregnancy, the control group (C) was fed a diet containing 20% casein, and the LP group was fed an isocaloric diet with 10% casein. Offspring pancreases were obtained at each PND and then processed. β and α cells were detected by immunohistochemistry, and cellular area and islet size were quantified. Islet cytoarchitecture and total area were similar in C and LP offspring at all ages studied. At the early ages (PNDs 7-21), the proportion of β cells was lower in LP than C offspring. The proportion of α cells was lower in LP than C offspring on PND 14 and higher on PND 21. The β/α-cell ratio was lower in LP compared with C offspring on PNDs 7 and 21 and higher on PND 36 (being similar on PNDs 14 and 110). We concluded that maternal protein restriction during pregnancy modifies offspring islet cell ontogeny by altering the proportions of islet sizes and by reducing the number of β cells postnatally, which may impact pancreatic function in adult life.

Chronic Protein Restriction in Mice Impacts Placental Function and Maternal Body Weight before Fetal Growth.

Mechanisms of resource allocation are essential for maternal and fetal survival, particularly when the availability of nutrients is limited. We investigated the responses of feto-placental development to maternal chronic protein malnutrition to test the hypothesis that maternal low protein diet produces differential growth restriction of placental and fetal tissues, and adaptive changes in the placenta that may mitigate impacts on fetal growth. C57BL/6J female mice were fed either a low-protein diet (6% protein) or control isocaloric diet (20% protein). On embryonic days E10.5, 17.5 and 18.5 tissue samples were prepared for morphometric, histological and quantitative RT-PCR analyses, which included markers of trophoblast cell subtypes. Potential endocrine adaptations were assessed by the expression of Prolactin-related hormone genes. In the low protein group, placenta weight was significantly lower at E10.5, followed by reduction of maternal weight at E17.5, while the fetuses became significantly lighter no earlier than at E18.5. Fetal head at E18.5 in the low protein group, though smaller than controls, was larger than expected for body size. The relative size and shape of the cranial vault and the flexion of the cranial base was affected by E17.5 and more severely by E18.5. The junctional zone, a placenta layer rich in endocrine and energy storing glycogen cells, was smaller in low protein placentas as well as the expression of Pcdh12, a marker of glycogen trophoblast cells. Placental hormone gene Prl3a1 was altered in response to low protein diet: expression was elevated at E17.5 when fetuses were still growing normally, but dropped sharply by E18.5 in parallel with the slowing of fetal growth. This model suggests that nutrients are preferentially allocated to sustain fetal and brain growth and suggests the placenta as a nutrient sensor in early gestation with a role in mitigating impacts of poor maternal nutrition on fetal growth.

Effect of supplementation of crystalline lysine on the performance of WL layers in tropics during summer.

A trial was conducted to evaluate the effect of lysine concentration in the diet of WL layers with constant ratio of other essential amino acids to lysine. Pullets (528) aged 25 to 36 weeks were fed with test diet containing two protein levels (13.36 and 15.78%) each with 5% concentration of lysine (0.50, 0.55, 0.60, 0.65, and 0.70) and a control with 17% CP and 0.70%, lysine. Each test diet was fed ad libitum to six replicates of eight birds for a period of 12 weeks. Egg production (EP), egg weight (EW), egg mass (EM), feed efficiency (g/g) (FE), body weight gain (BWG), Haugh unit (HU) and yolk colour (YC) were measured. Increased (P ≤ 0.05) EP, EW, EM, FE and BWG were obtained with increasing lysine concentration in diets. Whereas, feed intake/h/day, feed intake/egg, egg shell defects (ESD), mortality and shell thickness were not affected (P ≥ 0.05) by the concentration of lysine in diet. However, higher (P ≤ 0.05) HU score and YC were noticed at low lysine (0.50 %) concentrations. Based on this, it was concluded that WL layers (25-36 weeks) reared in open-sided houses in the tropics require approximately 0.70 % lysine (597.90 vs. 584.39 mg/h/day) in low (13.36% CP) and high (15.78% CP) protein groups in diets containing approximately 2700 kcal of ME/kg in summer.

Postnatal High Protein Intake Can Contribute to Accelerated Weight Gain of Infants and Increased Obesity Risk.

Worldwide, 38% of women are now overweight (BMI 25-30) or obese (BMI ≥30). There is increasing evidence that maternal obesity can result in unfavorable (epigenetic) pre- and postnatal programming of important genes of the offspring. Infants of overweight mothers show faster weight gain during infancy, which is associated with higher risk of obesity during childhood and adult life. This can have lifelong consequences such as increased risk of noncommunicable diseases. Many studies indicate that infants of obese and nonobese mothers who were fed traditional (high-protein) formulas gain more rapidly weight than breastfed infants. An updated meta-analysis (n = 1,150) indicates that infants from four continents who were fed a whey-based, low-protein (1.8 g/100 kcal) formula with an essential amino-acid profile closer to breast milk grow in accordance with the World Health Organization (WHO) growth standard (0-4 months). A new experimental low-protein (1.61-1.65 g protein/100 kcal) formula for infants between 3 and 12 months of age was recently tested in two randomized clinical trials. One trial in the general US population indicates lower weight between 4 and 12 months of age in infants fed the low-protein formula when compared to infants on the high-protein formula (p = 0.031). Weight gain was not inferior to the WHO growth standards. Longitudinal analysis of odds ratios from 4 to 12 months of age showed a lower incidence of infants with weight >85th percentile in the low-protein group compared with the high-protein group (p = 0.015). In the second trial, which was conducted in Chile and included infants of mothers with BMI >25, infants fed the low-protein formula gained less weight between 4 and 12 months (p = 0.022) and until 24 months (p = 0.031) than the high-protein group. Weight gain was similar to the breastfed reference group. In both trials, biomarkers of protein metabolism (insulin-like growth factor-1 and C-peptide) of the low-protein groups were closer to breastfed infants than the respective biomarkers of the high-protein groups. Health economic analyses indicate that feeding low-protein formulas to nonbreastfed infants would result in cost savings for both the individual and the society. Preventive measures against childhood and adult obesity should include promotion of breastfeeding for 6 months or longer, and use of low-protein formulas in nonbreastfed infants.