Short-term protein intake and stimulation of protein synthesis in stunted children with cystic fibrosis

Adherence to Dietary Recommendations, Nutrient Intake Adequacy and Diet Quality among Pediatric Cystic Fibrosis Patients: Results from the GreeCF Study

Nutrition is an important component of cystic fibrosis (CF) therapy, with a high-fat diet being the cornerstone of treatment. However, adherence to the dietary recommendations for CF appears suboptimal and burdensome for most children and adolescents with CF, leading to malnutrition, inadequate growth, compromised lung function and increased risk for respiratory infections. A cross-sectional approach was deployed to examine the degree of adherence to the nutrition recommendations and diet quality among children with CF. A total of 76 children were recruited from Aghia Sophia’s Children Hospital, in Athens, Greece. In their majority, participants attained their ideal body weight, met the recommendations for energy and fat intake, exceeding the goal for saturated fatty acids consumption. Carbohydrate and fiber intake were suboptimal and most participants exhibited low or mediocre adherence to the Mediterranean diet prototype. It appears that despite the optimal adherence to the energy and fat recommendations, there is still room for improvement concerning diet quality and fiber intake.

A randomized controlled trial of high parenteral protein feeding in septic children: the role of tumor necrosis factor-alpha-308 polymorphism

BACKGROUND Septic children cause high protein degradation and inadequate nutritional intake would worsen the outcomes. In addition, there are conflicting results of association between tumor necrosis factor-α (TNFA)-308 polymorphism and poorer outcomes. This study was aimed to investigate the impact of high protein feeding in septic children and to examine the role of the TNFA-308 polymorphism in outcome of sepsis. METHODS In this randomized controlled trial, septic children were randomly assigned to receive either high protein feeding (amino acid of 4 g/kg of body weight [kgBW]/day) or standard nutrient (amino acid of 2 g/kgBW/day) for three days in the pediatric intensive care unit of four hospitals in Indonesia. The patient’s enrollment was done between April 2016 and May 2017. The primary outcome was the pediatric logistic organ dysfunction (PELOD) score. TNFA-308 polymorphism was investigated using restriction fragment length polymorphism method in both groups. PELOD score was analyzed as mean differences and gene polymorphism was analyzed with mortality in a subgroup. RESULTS There were 40 children in each group. PELOD score on day-1 (22.4 versus 20.5, p = 0.429), day-2 (20.5 versus 19.8, p = 0.815), and day-3 (18.8 versus 19.8, p = 0.772) were not lower in high protein feeding compared to standard feeding. TNFA-308 polymorphism had no role in mortality of both groups (high protein, p = 0.426; standard, p = 0.456). CONCLUSIONS From this study, researchers concluded that a high protein intervention did not significantly decrease the PELOD score, length of stay, and duration of ventilator use in both groups.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when oral dietary and supplement intake has failed to achieve an adequate nutritional status. The use of this method of feeding is assessed on an individual basis taking into consideration the patients age and clinical status. This is a final update of a previously published review.

OBJECTIVES

To examine the evidence that in people with cystic fibrosis, supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 10 July 2019.Date of the most recent hand search of PubMed: 26 October 2018.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

The searches identified 44 trials; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are expensive and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement; but, efficacy has not been fully assessed by randomised controlled trials. It is acknowledged, however, that performing a randomised controlled trial would be difficult due to the ethics of withholding an intervention in a group of people whose nutritional status necessitates it.

Choline supplementation alters some amino acid concentrations with no change in homocysteine in children with cystic fibrosis and pancreatic insufficiency

The present study determined the plasma amino acid status in children with cystic fibrosis (CF) and pancreatic insufficiency (PI) in the modern medical and nutritional care setting and investigated the effect of choline supplementation on amino acid status. A total of 110 children aged 5 to 18 years with CF and PI were randomized to receive choline-enriched structured lipid (LYM-X-SORB) or placebo with similar energy and fat content. Plasma amino acids were measured at baseline and 3 and 12 months. We hypothesized that choline supplementation would result in lower plasma homocysteine concentrations in children with CF. At baseline, dietary protein intake was high and the amino acid profile was within laboratory reference ranges in most participants. Alanine and cysteine were elevated in 24% and 36% of participants, respectively. Children with baseline alanine above reference range had improved weight, body mass index, and fat-free mass. Low homocysteine was found in 62% of children 11 years and older. After 3 and 12 months, there was no effect of choline supplementation on methionine or homocysteine status. Compared with placebo, choline supplementation resulted in increased glycine and decreased threonine, histidine, valine, and total branch chained amino acids at 12 months. In conclusion, daily choline supplementation with LYM-X-SORB did not alter methionine-homocysteine metabolism but did result in alterations in other amino acids in children with CF and PI.

The effect of short-term high versus normal protein intake on whole-body protein synthesis and balance in children following cardiac surgery: a randomized double-blind controlled clinical trial

Background

Infants undergoing cardiac surgery are at risk of a negative protein balance, due to increased proteolysis in response to surgery and the cardiopulmonary bypass circuit, and limited intake. The aim of the study was to quantify the effect on protein kinetics of a short-term high-protein (HP) diet in infants following cardiac surgery.

Methods

In a prospective, double-blinded, randomized trial we compared the effects of a HP (5 g · kg⁻¹ · d⁻¹) versus normal protein (NP, 2 g · kg⁻¹ · d⁻¹) enteral diet on protein kinetics in children <24 months, on day 2 following surgical repair of congenital heart disease. Valine kinetics and fractional albumin synthesis rate (FSR_alb) were measured with mass spectrometry using [1-¹³C]valine infusion. The Mann–Whitney U test was used to investigate differences between group medians. Additionally, the Hodges-Lehmann procedure was used to create a confidence interval with a point estimate of median differences between groups.

Results

Twenty-eight children (median age 9 months, median weight 7 kg) participated in the study, of whom in only 20 subjects isotopic data could be used for final calculations. Due to underpowering of our study, we could not draw conclusions on the primary outcome parameters. We observed valine synthesis rate of 2.73 (range: 0.94 to 3.36) and 2.26 (1.85 to 2.73) μmol · kg⁻¹ · min⁻¹ in the HP and NP diet, respectively. The net valine balance was 0.54 (−0.73 to 1.75) and 0.24 (−0.20 to 0.63) μmol · kg⁻¹ · min⁻¹ in the HP and NP group. Between groups, there was no difference in FSR_alb. We observed increased oxidation and BUN in the HP diet, compared to the NP diet, as a plausible explanation of the metabolic fate of surplus protein.

Conclusions

It is plausible that the surplus protein in the HP group has caused the increase of valine oxidation and ureagenesis, compared to the NP group. Because too few patients had completed the study, we were unable to draw conclusions on the effect of a HP diet on protein synthesis and balance. We present our results as new hypothesis generating data.

Trial registration

Dutch Trial Register NTR2334.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when oral dietary and supplement intake has failed to achieve an adequate nutritional status. The use of this method of feeding is assessed on an individual basis taking into consideration the patients age and clinical status.

OBJECTIVES

To examine the evidence that in people with cystic fibrosis, supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 13 February 2015.Date of the most recent hand search of PubMed and conference abstract books: 13 February 2015.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

The searches identified 38 trials; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are expensive and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement; but, efficacy has not been fully assessed by randomised controlled trials. It is acknowledged, however, that performing a randomised controlled trial would be difficult due to the ethics of withholding an intervention in a group of patients whose nutritional status necessitates it.

Protein is an important but undervalued macronutrient in the nutritional care of patients with cystic fibrosis

PURPOSE OF REVIEW

Achieving an optimal nutritional status in patients with cystic fibrosis (CF) is important to maintain better pulmonary function, physical performance, and to prolong survival. So far, nutrition care in CF has mainly focused on fat intake and achieving energy balance, but there is increasing information on the clinical importance of muscle maintenance and protein intake in CF.

RECENT FINDINGS

Low muscle mass is consistently associated with pulmonary decline, bone mineral loss, and poor survival in CF. High energy and fat intake contributes to an increased prevalence of overweight and obesity in CF. Obesity per se is not related to better lung function in CF and has negative metabolic and clinical consequences, particularly when muscle wasting is present. Protein digestion capacity is severely impaired in CF, but high protein intake is needed and essential amino acid mixtures appear highly anabolic even in those with severe muscle loss.

SUMMARY

Body composition assessment and achieving protein balance in the routine care in CF is important to prevent muscle loss and further improve the clinical and overall outcome of these patients. New approaches are needed to optimize the interaction between high essential amino-acid-rich protein intake and pancreatic enzyme regimen in CF. The optimal level of protein intake needs to be assessed in clinically stable CF patients as well as in those recovering from an acute exacerbation.

Dietary essential amino acids are highly anabolic in pediatric patients with cystic fibrosis

BACKGROUND

Current nutritional approaches have been partially successful in Cystic Fibrosis (CF). Essential amino acids mixtures with high Leucine levels (EAA) have anabolic properties in catabolic conditions, however data in CF are lacking.

METHODS

On two days according a randomized crossover design, 15 pediatric CF patients ingested 6.7 g EAA versus mixture of total amino acids as present in whey. Whole body protein and Arginine metabolism (as EAA lack Arginine) were assessed by stable isotope methodology.

RESULTS

Protein synthesis (P<0.05) but not protein breakdown was higher after EAA and 70% higher values for net anabolism (P<0.001)were found both in patients with and without nutritional failure. Arginine turnover was lower (P<0.001) and de novo Arginine synthesis tended lower (P=0.09) after EAA. Nitric oxide synthesis was not different.

CONCLUSIONS

CF patients are highly responsive to EAA intake independent of their nutritional status. Addition of Arginine to the EAA mixture may be warranted in CF.

Role of specific dietary amino acids in clinical conditions

In a variety of chronic and acute disease states, alterations in protein synthesis, breakdown and protein turnover rates occur that are related to the loss of body protein and skeletal muscle wasting. A key observation is the stimulation of protein breakdown in muscle and the stimulation of protein synthesis in the splanchnic area; mainly liver. An altered splanchnic extraction of amino acids as well as an anabolic resistance to dietary protein, related to stress, disuse and aging play a key role in the pathogenesis of muscle wasting in these conditions. To overcome these factors, specific dietary protein and amino acid diets have been introduced. The main focus of these diets is the quantity and quality of dietary proteins and whether a balanced mixture or solely dietary essential amino acids are required with or without higher intake levels of specific amino acids. Specifically in cancer patients, stimulated muscle protein synthesis has been obtained by increasing the amount of protein in a meal and by providing additional leucine. Also in other chronic diseases such as chronic obstructive pulmonary disease and cystic fibrosis, meals with specific dietary proteins and specific combinations of dietary essential amino acids are able to stimulate anabolism. In acute diseases, a special role for the amino acid arginine and its precursor citrulline as anabolic drivers has been observed. Thus, there is growing evidence that modifying the dietary amino acid composition of a meal will positively influence the net balance between muscle protein synthesis and breakdown, leading to muscle protein anabolism in a variety of chronic and acute disease states. Specific amino acids with anabolic potential are leucine, arginine and citrulline.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when oral dietary and supplement intake has failed to achieve an adequate nutritional status. The use of this method of feeding is assessed on an individual basis taking into consideration the patients age and clinical status.

OBJECTIVES

To examine the evidence that in people with cystic fibrosis, supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases.Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 03 September 2012.Date of the most recent hand search of PubMed and conference abstract books: 15 June 2012.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Thirty-one trials were identified by the searches; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are expensive and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement; but, efficacy has not been fully assessed by randomised controlled trials. It is acknowledged, however, that performing a randomised controlled trial would be difficult due to the ethics of withholding an intervention in a group of patients whose nutritional status necessitates it.

Nutritional practices and their relationship to clinical outcomes in critically ill children--an international multicenter cohort study*

OBJECTIVES

To examine factors influencing the adequacy of energy and protein intake in the pediatric intensive care unit and to describe their relationship to clinical outcomes in mechanically ventilated children.

DESIGN, SETTING, PATIENTS

We conducted an international prospective cohort study of consecutive children (ages 1 month to 18 yrs) requiring mechanical ventilation longer than 48 hrs in the pediatric intensive care unit. Nutritional practices were recorded during the pediatric intensive care unit stay for a maximum of 10 days, and patients were followed up for 60 days or until hospital discharge. Multivariate analysis, accounting for pediatric intensive care unit clustering and important confounding variables, was used to examine the impact of nutritional variables and pediatric intensive care unit characteristics on 60-day mortality and the prevalence of acquired infections.

MAIN RESULTS

31 pediatric intensive care units in academic hospitals in eight countries participated in this study. Five hundred patients with mean (SD) age 4.5 (5.1) yrs were enrolled and included in the analysis. Mortality at 60 days was 8.4%, and 107 of 500 (22%) patients acquired at least one infection during their pediatric intensive care unit stay. Over 30% of patients had severe malnutrition on admission, with body mass index z-score >2 (13.2%) or <-2 (17.1%) on admission. Mean prescribed goals for daily energy and protein intake were 64 kcals/kg and 1.7 g/kg respectively. Enteral nutrition was used in 67% of the patients and was initiated within 48 hrs of admission in the majority of patients. Enteral nutrition was subsequently interrupted on average for at least 2 days in 357 of 500 (71%) patients. Mean (SD) percentage daily nutritional intake (enteral nutrition) compared to prescribed goals was 38% for energy and 43% (44) for protein. A higher percentage of goal energy intake via enteral nutrition route was significantly associated with lower 60-day mortality (Odds ratio for increasing energy intake from 33.3% to 66.6% is 0.27 [0.11, 0.67], p = .002). Mortality was higher in patients who received parenteral nutrition (odds ratio 2.61 [1.3, 5.3], p = .008). Patients admitted to units that utilized a feeding protocol had a lower prevalence of acquired infections (odds ratio 0.18 [0.05, 0.64], p = .008), and this association was independent of the amount of energy or protein intake.

CONCLUSIONS

Nutrition delivery is generally inadequate in mechanically ventilated children across the world. Intake of a higher percentage of prescribed dietary energy goal via enteral route was associated with improved 60-day survival; conversely, parenteral nutrition use was associated with higher mortality. Pediatric intensive care units that utilized protocols for the initiation and advancement of enteral nutrient intake had a lower prevalence of acquired infections. Optimizing nutrition therapy is a potential avenue for improving clinical outcomes in critically ill children.

Low-dose glucocorticoid treatment affects multiple aspects of intermediary metabolism in healthy humans: a randomised controlled trial

AIM/HYPOTHESIS

To assess whether low-dose glucocorticoid treatment induces adverse metabolic effects, as is evident for high glucocorticoid doses.

METHODS

In a randomised placebo-controlled double-blind (participants and the investigators who performed the studies and assessed the outcomes were blinded) dose-response intervention study, 32 healthy men (age 22 ± 3 years; BMI 22.4 ± 1.7 kg/m(2)) were allocated to prednisolone 7.5 mg once daily (n = 12), prednisolone 30 mg once daily (n = 12), or placebo (n = 8) for 2 weeks using block randomisation. Main outcome measures were glucose, lipid and protein metabolism, measured by stable isotopes, before and at 2 weeks of treatment, in the fasted state and during a two-step hyperinsulinaemic clamp conducted in the Clinical Research Unit of the Academic Medical Centre, Amsterdam, the Netherlands

RESULTS

Prednisolone, compared with placebo, dose dependently and significantly increased fasting plasma glucose levels, whereas only prednisolone 30 mg increased fasting insulin levels (29 ± 15 pmol/l). Prednisolone 7.5 mg and prednisolone 30 mg decreased the ability of insulin to suppress endogenous glucose production (by 17 ± 6% and 46 ± 7%, respectively, vs placebo). Peripheral glucose uptake was not reduced by prednisolone 7.5 mg, but was decreased by prednisolone 30 mg by 34 ± 6% (p < 0.0001). Compared with placebo, prednisolone treatment tended to decrease lipolysis in the fasted state (p = 0.062), but both prednisolone 7.5 mg and prednisolone 30 mg decreased insulin-mediated suppression of lipolysis by 11 ± 5% and 34 ± 6%, respectively. Finally, prednisolone treatment increased whole-body proteolysis during hyperinsulinaemia, which tended to be driven by prednisolone 30 mg (5 ± 2%; p = 0.06). No side effects were reported by the study participants. All participants completed the study and were analysed.

CONCLUSIONS/INTERPRETATION

Not only at high doses but also at low doses, glucocorticoid therapy impaired intermediary metabolism by interfering with the metabolic actions of insulin on liver and adipose tissue. These data indicate that even low-dose glucocorticoids may impair glucose tolerance when administered chronically.

TRIAL REGISTRATION

ISRCTN83991850.

The HepaRG cell line is suitable for bioartificial liver application

For bioartificial liver application, cells should meet the following minimal requirements: ammonia elimination, drug metabolism and blood protein synthesis. Here we explore the suitability of HepaRG cells, a human cell line reported to differentiate into hepatocyte clusters and surrounding biliary epithelial-like cells at high density and after exposure to dimethyl sulfoxide (DMSO). The effect of carbamoyl-glutamate (CG), an activator of urea cycle enzyme carbamoylphosphate synthetase (CPS) was studied additionally. The effects of DMSO and/or CG were assessed in presence of (15)NH(4)Cl on HepaRG cells in monolayer. We tested hepatocyte-specific functions at transcript and biochemical level, cell damage parameters and performed immunostainings. Ureagenesis, ammonia/galactose elimination and albumin, glutamine synthetase and CPS transcript levels were higher in -DMSO than +DMSO cultures, probably due to a higher cell content and/or cluster-neighbouring regions contributing to their functionality. DMSO treatment increased cytochrome P450 (CYP) transcript levels and CYP3A4 activity, but also cell damage and repressed hepatic functionality in cluster-neighbouring regions. The levels of ammonia elimination, apolipoprotein A-1 production, and transcription of CYP3A4, CYP2B6 and albumin reached those of primary hepatocytes in either the + or -DMSO cultures. Preconditioning with CG increased conversion of (15)NH(4)Cl into (15)N-urea 4-fold only in -DMSO cultures. Hence, HepaRG cells show high metabolic and synthetic functionality in the absence of DMSO, however, their drug metabolism is only high in the presence of DMSO. An unparalleled broad hepatic functionality, suitable for bioartificial liver application, can be accomplished by combining CG treated -DMSO cultures with +DMSO cultures.

Increased protein-energy intake promotes anabolism in critically ill infants with viral bronchiolitis: a double-blind randomised controlled trial

OBJECTIVE

The preservation of nutritional status and growth is an important aim in critically ill infants, but difficult to achieve due to the metabolic stress response and inadequate nutritional intake, leading to negative protein balance. This study investigated whether increasing protein and energy intakes can promote anabolism. The primary outcome was whole body protein balance, and the secondary outcome was first pass splanchnic phenylalanine extraction (SPE(Phe)).

DESIGN

This was a double-blind randomised controlled trial. Infants (n=18) admitted to the paediatric intensive care unit with respiratory failure due to viral bronchiolitis were randomised to continuous enteral feeding with protein and energy enriched formula (PE-formula) (n=8; 3.1 ± 0.3 g protein/kg/24 h, 119 ± 25 kcal/kg/24 h) or standard formula (S-formula) (n=10; 1.7 ± 0.2 g protein/kg/24 h, 84 ± 15 kcal/kg/24 h; equivalent to recommended intakes for healthy infants <6 months). A combined intravenous-enteral phenylalanine stable isotope protocol was used on day 5 after admission to determine whole body protein metabolism and SPE(Phe).

RESULTS

Protein balance was significantly higher with PE-formula than with S-formula (PE-formula: 0.73 ± 0.5 vs S-formula: 0.02 ± 0.6 g/kg/24 h) resulting from significantly increased protein synthesis (PE-formula: 9.6 ± 4.4, S-formula: 5.2 ± 2.3 g/kg/24 h), despite significantly increased protein breakdown (PE-formula: 8.9 ± 4.3, S-formula: 5.2 ± 2.6 g/kg/24 h). SPE(Phe) was not statistically different between the two groups (PE-formula: 39.8 ± 18.3%, S-formula: 52.4 ± 13.6%).

CONCLUSIONS

Increasing protein and energy intakes promotes protein anabolism in critically ill infants in the first days after admission. Since this is an important target of nutritional support, increased protein and energy intakes should be preferred above standard intakes in these infants. Dutch Trial Register number: NTR 515.

Dietary supplementation with pressurized whey in patients with cystic fibrosis

Cystic fibrosis (CF) is characterized by malnutrition, chronic pulmonary inflammation, and oxidative stress. Whey protein is rich in sulfhydryl groups and is recognized for its ability to increase glutathione and reduce oxidative stress. Previously, we have shown that supplementation with whey increased intracellular glutathione levels in patients with CF. We have subsequently shown that hyperbaric pressure treatment of whey protein promotes the release of novel peptides for absorption, increases intracellular glutathione in healthy subjects, and reduces in vitro production of interleukin (IL)-8. We hypothesized that pressurized whey supplementation in children and adults with CF could have significant nutritional and anti-inflammatory benefits. A pilot open-label study of 1-month dietary supplementation with pressurized whey in CF patients was undertaken to assess the effects. Twenty-seven patients with CF (nine children, 18 adults) were enrolled. The dose of pressurized whey was 20 g/day in patients less than 18 years of age and 40 g/day in older patients. Anthropometric measures, pulmonary function, serum C-reactive protein (CRP), whole blood glutathione, and whole blood IL-8 and IL-6 responses to phytohemagglutinin (PHA) stimulation were measured at baseline and at 1 month. Three adults withdrew (one with gastrointestinal side effects, two with acute infection). Both children and adults showed enhancements in nutritional status, as assessed by body mass index. Children showed improvement in lung function (forced expiratory volume in 1 second). The majority of patients with an initially elevated CRP showed a decrease. PHA-stimulated IL-8 responses tended to decrease in the adults. Whole blood glutathione levels did not change. Thus, oral supplementation with pressurized whey improves nutritional status and can have additional beneficial effects on inflammation in patients with CF.

Intermittent fasting does not affect whole-body glucose, lipid, or protein metabolism

BACKGROUND

Intermittent fasting (IF) was shown to increase whole-body insulin sensitivity, but it is uncertain whether IF selectively influences intermediary metabolism. Such selectivity might be advantageous when adapting to periods of food abundance and food shortage.

OBJECTIVE

The objective was to assess effects of IF on intermediary metabolism and energy expenditure.

DESIGN

Glucose, glycerol, and valine fluxes were measured after 2 wk of IF and a standard diet (SD) in 8 lean healthy volunteers in a crossover design, in the basal state and during a 2-step hyperinsulinemic euglycemic clamp, with assessment of energy expenditure and phosphorylation of muscle protein kinase B (AKT), glycogen synthase kinase (GSK), and mammalian target of rapamycine (mTOR). We hypothesized that IF selectively increases peripheral glucose uptake and lowers proteolysis, thereby protecting protein stores.

RESULTS

No differences in body weight were observed between the IF and SD groups. Peripheral glucose uptake and hepatic insulin sensitivity during the clamp did not significantly differ between the IF and SD groups. Likewise, lipolysis and proteolysis were not different between the IF and SD groups. IF decreased resting energy expenditure. IF had no effect on the phosphorylation of AKT but significantly increased the phosphorylation of glycogen synthase kinase. Phosphorylation of mTOR was significantly lower after IF than after the SD.

CONCLUSIONS

IF does not affect whole-body glucose, lipid, or protein metabolism in healthy lean men despite changes in muscle phosphorylation of GSK and mTOR. The decrease in resting energy expenditure after IF indicates the possibility of an increase in weight during IF when caloric intake is not adjusted. This study was registered at www.trialregister.nl as NTR1841.

Nutrition management of pediatric patients who have cystic fibrosis

Since the identification of cystic fibrosis (CF) in the 1940s, nutrition care of patients who have CF has been a challenge. Through optimal caloric intake and careful management of malabsorption, patients are expected to meet genetic potential for growth. Yet factors beyond malabsorption, including nutrient activity at the cellular level, may influence growth and health. This article reviews nutrition topics frequently discussed in relationship to CF and presents intriguing new information describing nutrients currently being studied for their impact on overall health of patients who have CF.

Nevirapine Increases High-Density Lipoprotein Cholesterol Concentration by Stimulation of Apolipoprotein A-I Production

Objective— The purpose of this study was to investigate the mechanism by which the nonnucleoside reverse transcriptase inhibitor (NNRTI) nevirapine (NVP) increases high-density lipoprotein cholesterol (HDLc) in treatment-experienced human immunodeficiency virus-1 (HIV-1)–infected patients.

Methods and Results— Twelve HIV-1 infected patients, with stably suppressed HIV-1 viral load using AZT/3TC/abacavir for ≥6 months, added NVP to their current antiretroviral regimen. Patients received a primed bolus infusion of the stable isotope L-[1- 13 C]-valine for 12 hours before, as well as 6 and 24 weeks after, the addition of NVP to study apolipoprotein A-I (apoA-I) kinetics. Absolute production rate (APR) and fractional catabolic rate (FCR) of apoA-I were calculated using SAAM-II modeling. Major HDLc-modulating enzymes were assessed. Plasma apoA-I and HDLc levels increased significantly after 24 weeks of treatment by, respectively, 13±4% ( P =0.01) and 16±6% ( P =0.015). Concomitantly, apoA-I production rate at 24 weeks increased by 17±7% ( P =0.04). ApoA-I catabolism did not change. A modest increase of lecithin:cholesterol acyltransferase and cholesteryl ester transfer protein activity was observed.

Conclusions— NVP increases apoA-I production, which contributes to the HDLc increase after introduction of NVP-containing regimens. In view of the potent antiatherogenic effects of apoA-I, the observed increase may contribute to the favorable cardiovascular profile of NVP.

Enteral tube feeding for cystic fibrosis

BACKGROUND

Enteral tube feeding is routinely used in many cystic fibrosis centres when weight for height percentage is less than 85%, when there has been weight loss for longer than a two-month period or when there has been no weight gain for two to three months (under five years old) or for six months (over five years old).

OBJECTIVES

To examine the evidence that in people with cystic fibrosis supplemental enteral tube feeding improves nutritional status, respiratory function, and quality of life without significant adverse effects.

SEARCH STRATEGY

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also contacted the companies that market enteral feeds and reviewed their databases. Date of the most recent search of the Group's Cystic Fibrosis Trials Register: November 2007.

SELECTION CRITERIA

All randomised controlled trials comparing supplemental enteral tube feeding for one month or longer with no specific intervention in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Thirteen trials were identified by the search; however, none were eligible for inclusion in this review.

MAIN RESULTS

There are no trials included in this review.

AUTHORS' CONCLUSIONS

Supplemental enteral tube feeding is widely used throughout the world to improve nutritional status in people with cystic fibrosis. The methods mostly used, nasogastric or gastrostomy feeding, are invasive, expensive, and may have a negative effect on self-esteem and body image. Reported use of enteral tube feeding suggests that it results in nutritional and respiratory improvement and it is disappointing that their efficacy has not been fully assessed by randomised controlled trials. With the more frequent recommendations to use enteral tube feeding as an early rather than a late intervention, this systematic review identifies the need for a multicentre, randomised controlled trial assessing both efficacy and possible adverse effects of enteral tube feeding in cystic fibrosis. There are no trials included in the review and we have not identified any relevant trials up to November 2007. We therefore do not plan to update this review until new trials are published.

Nutritional goals, prescription and delivery in a pediatric intensive care unit

BACKGROUND & AIMS

The aim of this study was to compare prescription and delivery of nutrition to predefined nutritional targets, and identify risk factors associated with inadequate nutritional intake.

METHODS

In 84 mechanically ventilated critically ill children with length of stay on the PICU of at least 3 days, we observed prescribed and delivered percentages of predefined targets for intake of calories and macronutrients during a 10-months study period. Factors associated with inadequate intake were identified.

RESULTS

On the third day of admission 92.9% of the patients received nutritional therapy. The caloric goal was reached on day 5, mainly supplied by fat and carbohydrates. Mean actual daily protein delivery was about 75% of the target during the entire study period. Use of catecholamines or neuromuscular blocking agents was a risk factor for caloric undernutrition, whereas there were no specific risk factors for overnutrition.

CONCLUSIONS

Nutritional therapy should be started in the early phase of critical illness, including adequate supply of protein. In order to prevent deficits to accumulate, parenteral nutrition should be added in an early phase, if nutritional needs cannot be met by enteral nutrition.

Nutrition in pediatric lung disease

The respiratory system exists in an oxygenated milieu and is recurrently exposed to both endogenous and exogenous oxidants and irritants. A variety of dietary-dependent defenses have evolved to protect the lungs. These comprise vitamins, proteins, polyphenols, fatty acids and co-factors. This is a brief review of oxidant sources and the antioxidant system, as pertains to the respiratory system. The challenge to both clinicians and investigators is to understand how defenses are integrated and coordinated so that enhanced protection can be delivered.