Quantitative histologic evaluation reveals different degree of liver atrophy in cachectic and starved dogs.

Cases of neglect in dogs are among the forensic cases submitted most commonly for postmortem examination. Starvation is a form of primary protein-energy malnutrition in which the availability of food is severely restricted or absent; cachexia is a form of protein-energy malnutrition secondary to progressive metabolic derangement during chronic diseases. Despite both conditions leading to an emaciated appearance of the cadaver, discrimination between the two is crucial in forensic cases. We hypothesized that among emaciated dogs, the degree of liver atrophy in starved animals is higher than in cachectic ones, and that this can be investigated microscopically, regardless of the degree of cadaver decomposition. We studied 46 animals: 23 starved, 11 cachectic, and 12 control dogs. Portal tracts were identified by the presence of a bile duct and associated vascular structures recognizable by a thin rim of collagen still visible regardless of the degree of cadaver decomposition. The number of portal tracts per lpf (10×) was used as an indirect measure of atrophy. The number of portal tracts in starved dogs was significantly higher (p < 0.01) compared to both cachectic and control dogs, indicating a higher degree of liver atrophy in starvation. Measuring the density of portal tracts offers a reliable additional tool for discrimination between starvation and cachexia.

Maternal Spirulina supplementation during pregnancy and lactation partially prevents oxidative stress, glial activation and neuronal damage in protein malnourished F1 progeny.

Protein malnutrition (PMN) is a global health issue but most prevalent in Africa and Asia. It exerts detrimental effect on structural and physiological aspects of hippocampal circuitry. Despite accumulating evidence for PMN induced changes in nervous system, relatively very little is known about how maternal nutritional supplementation during malnutrition affects glial cells and neurons. Herein, we aimed to investigate the effects of maternal Spirulina supplementation against PMN induced oxidative stress, reactive gliosis and neuronal damage in hippocampus of F1 progeny. Three months old healthy Sprague Dawley females (n = 24) were shifted to normoprotein (NC; 20% protein) and low protein (LP; 8% protein) diets 15 days before conception. The NC and LP group females were subdivided into two groups according to Spirulina supplementation (400 mg/kg/b.wt. orally throughout gestation and lactation period): normal control with Spirulina (NC SPI) and low protein with Spirulina supplemented group (LP SPI). F1 progeny born were used in present study. Thus, building on earlier results of ameliorated neurobehavioral and cognitive abilities in Spirulina supplemented protein deprived rats, the present study incorporates neurochemical and morphometric analysis of glial cells and neurons and revealed that maternal Spirulina consumption partially prevented the PMN associated neuropathological alterations in terms of attenuated oxidative brain damage, reduced reactive gliosis and apoptotic cell population, improved dendritic branch complexity with few damaged neurons and enhanced mushroom shaped spine density. The results suggest that cellular changes in hippocampus after PMN are partially restored after maternal Spirulina supplementation and one could envision intervention approaches using Spirulina against malnutrition.

Adult characteristics of survivors of early life malnutrition in an impoverished population.

BACKGROUND & AIMS: To determine the characteristics of adults who survived early life malnutrition (ELM) and the possible associated factors. The setting is an impoverished community in Kenya. The coastal region of Kenya has a high prevalence of acute protein-energy-malnutrition and stunting. METHODS: Observational cross-sectional survey where 872 skeletally mature adults of African origin, were surveyed in a period of three months. A discrimination tool to detect ELM survivors was created. Personal, historical and family data were collected in a semi-structured questionnaire. Various observations and body measurements were done. The subjects were grouped into two, those with ELM (Group1), and those without (Group2). RESULTS: Group1 had 242 participants, 49.8% males, mean age of 49.1 ± 8.7 years. Group2 had 630 participants, 48.3% males, mean age 41.0 ± 9.7 years. The phenotypic characteristics included height, BMI, and head circumference (P < 0.05). Developmental characteristics were duration of schooling, occupation and income (P < 0.001). Factors associated with malnutrition were County of origin, parental education, parental occupation, and family size (P < 0.001). CONCLUSIONS: There are discernible phenotypic and developmental characteristics associated with adult survivors of ELM. The predisposing factors for ELM are location of birth, parental education and occupation, and family size.

Mineral Disorders in Adult Inpatients Receiving Parenteral Nutrition. Is Older Age a Contributory Factor?

BACKGROUND: Parenteral nutrition (PN)-dependent adults and elderly individuals who are admitted to hospital treatment are potentially susceptible to mineral disorder complications due to depleted physiological reserves, loss of lean body mass, and increased fat mass, thus worsening inflammation. AIM: The purpose of this study is to evaluate the prevalence of hypophosphatemia, hypokalemia, and hypomagnesaemia prior and within the first 7 days of PN infusion. Furthermore, whether malnutrition and old age are associated with these disorders was also investigated. METHODS: This study included a historical cohort of adult patients, and 1,040 patients whose information was prospectively entered in the database were evaluated. RESULTS: Of the 781 patients, 27.3% were ≥65 years, 80.9% had undergone surgical treatment, 74.3% were in the intensive care unit, and 17.9% died during the hospitalization period. About 17.1% patients were malnourished. Protein energy malnutrition (PEM) was observed in 31.9% of the elderly patients and 27.1% of adults in general. Hypophosphatemia, hypokalemia, and hypomagnesemia were more prevalent before the start of PN infusion (D0: 214 [18.4%]), and new events were more common during the first 2 days of PN infusion (D1: 283 [23.1%]; D2: 243 [20.1%]. Elderly patients were more susceptible to developing hypophosphatemia (odds ratio [OR]: 1.69; 95% confidence interval [CI]: 1.29-2.19; p<0.001). Patients with PEM were also more susceptible to hypophosphatemia (OR: 3.75; 95% CI: 1.13-12.47; p=0.036). CONCLUSION: Hypophosphatemia, hypokalemia, and hypomagnesemia were frequently observed in hospitalized adults and elderly patients before and particularly during the first 2 days of PN infusion. Elderly patients and patients with PEM are more susceptible to developing hypophosphatemia.

Protein Malnutrition Pre- and Postnatal and Nutritional Rehabilitation Modulates the Morphology of Muscle Fibers in Wistar Rats.

This study investigated the effects of pre- and postnatal conditions of protein deficiency followed to nutritional rehabilitation in the morphology of skeletal muscle. Twelve Wistar male rats were distributed in two groups: nourished (N), with normal protein diet and undernourished (U), with low protein diet. The respective diet was maintained until animals completed 21 days of life. After that, part of group U (n = 4) received normal protein diet, forming a third group, renourished group (R). Forty-two-day-old animals were euthanized and we performed histopathological and morphometric analysis of the soleus muscle. Analysis stained in hematoxylin and eosin (H&E) of the group N revealed polygonal and equidistant muscle fibers, with normal distribution in muscle fascicles. However, D group had rounded and disorganized fibers with different distances between them in muscle fascicles. R group presented muscle fibers with several formats, polygonal and rounded, and some muscle fascicles starting the reorganization process. In N group, analysis of the connective tissue showed predominance of type I collagen and a lower amount collagen type III, both well organized. Whereas U group had a predominance of disorganized type III collagen, in R group, there was return of type I collagen, but partially organized. Muscle fiber area of U (163.18 ± 52.55 µm2) and R (381.79 ± 26.62 µm2) groups was smaller than N (1229.2 µm2 ± 61.12 µm2). Muscle fibers density of groups U (3369 ± 1226 fibers/mm2) and R (1979 ± 28 fibers/mm2) was larger than N (830 ± 113 fibers/mm2). The nutritional rehabilitation in the present study showed an attempt of reorganization of the muscle tissue.

The influence of protein malnutrition on biological and immunomodulatory aspects of bone marrow mesenchymal stem cells.

Tissues that require a great supply of nutrients and possess high metabolic demands, such as lympho-hemopoietics tissues, are the first to be affected by protein malnutrition (PM). Thus, PM directly affects hemopoiesis and the production and function of immune cells. Consequently, malnourished individuals are more susceptible to infections. Mesenchymal stem cells (MSCs) have immunomodulatory properties and are important in the formation of lympho-hemopoietic stroma. Since an adequate supply of nutrients is essential to sustain stroma formation, which is mainly constituted of MSCs and differentiated cells originated from them, this study investigated whether PM would influence some biological and immunomodulatory aspects of MSCs. Two-month-old Balb/c mice were divided into control and malnourished groups receiving normoproteic or hypoproteic diets, respectively (12% and 2% of protein) for 28 days. MSCs obtained from control (MSCct) and malnourished (MSCmaln) animals were characterized. In addition, the proliferation rate and cell cycle protein expression were determined, but no differences in these parameters were observed. In order to evaluate whether PM affects the immunomodulatory properties of MSCs, the expression of NFκB and STAT-3, and the production of IL-1α, IL-1ß, IL-6, IL-10, TGF-ß and TNF-α by MSCs were assessed. MSCmaln expressed lower levels of NF-κB and the production of IL-1ß, IL-6 and TGF-ß was significantly influenced by PM. Furthermore, MSCct and MSCmaln culture supernatants affected lymphocyte and macrophage proliferation. However, MSCmaln did not reduce the production of IFN-γ nor stimulate the production of IL-10 in lymphocytes in the same manner as observed in MSCct. Overall, this study implied that PM modifies immunosuppressive properties of MSCs.

PEX2 is the E3 ubiquitin ligase required for pexophagy during starvation.

Peroxisomes are metabolic organelles necessary for anabolic and catabolic lipid reactions whose numbers are highly dynamic based on the metabolic need of the cells. One mechanism to regulate peroxisome numbers is through an autophagic process called pexophagy. In mammalian cells, ubiquitination of peroxisomal membrane proteins signals pexophagy; however, the E3 ligase responsible for mediating ubiquitination is not known. Here, we report that the peroxisomal E3 ubiquitin ligase peroxin 2 (PEX2) is the causative agent for mammalian pexophagy. Expression of PEX2 leads to gross ubiquitination of peroxisomes and degradation of peroxisomes in an NBR1-dependent autophagic process. We identify PEX5 and PMP70 as substrates of PEX2 that are ubiquitinated during amino acid starvation. We also find that PEX2 expression is up-regulated during both amino acid starvation and rapamycin treatment, suggesting that the mTORC1 pathway regulates pexophagy by regulating PEX2 expression levels. Finally, we validate our findings in vivo using an animal model.

Protein malnutrition potentiates the amplifying pathway of insulin secretion in adult obese mice.

Pancreatic beta cell (ß) dysfunction is an outcome of malnutrition. We assessed the role of the amplifying pathway (AMP PATH) in ß cells in malnourished obese mice. C57Bl-6 mice were fed a control (C) or a low-protein diet (R). The groups were then fed a high-fat diet (CH and RH). AMP PATH contribution to insulin secretion was assessed upon incubating islets with diazoxide and KCl. CH and RH displayed increased glucose intolerance, insulin resistance and glucose-stimulated insulin secretion. Only RH showed a higher contribution of the AMP PATH. The mitochondrial membrane potential of RH was decreased, and ATP flux was unaltered. In RH islets, glutamate dehydrogenase (GDH) protein content and activity increased, and the AMP PATH contribution was reestablished when GDH was blunted. Thus, protein malnutrition induces mitochondrial dysfunction in ß cells, leading to an increased contribution of the AMP PATH to insulin secretion through the enhancement of GDH content and activity.

Fidelity in Animal Modeling: Prerequisite for a Mechanistic Research Front Relevant to the Inflammatory Incompetence of Acute Pediatric Malnutrition.

Inflammatory incompetence is characteristic of acute pediatric protein-energy malnutrition, but its underlying mechanisms remain obscure. Perhaps substantially because the research front lacks the driving force of a scholarly unifying hypothesis, it is adrift and research activity is declining. A body of animal-based research points to a unifying paradigm, the Tolerance Model, with some potential to offer coherence and a mechanistic impetus to the field. However, reasonable skepticism prevails regarding the relevance of animal models of acute pediatric malnutrition; consequently, the fundamental contributions of the animal-based component of this research front are largely overlooked. Design-related modifications to improve the relevance of animal modeling in this research front include, most notably, prioritizing essential features of pediatric malnutrition pathology rather than dietary minutiae specific to infants and children, selecting windows of experimental animal development that correspond to targeted stages of pediatric immunological ontogeny, and controlling for ontogeny-related confounders. In addition, important opportunities are presented by newer tools including the immunologically humanized mouse and outbred stocks exhibiting a magnitude of genetic heterogeneity comparable to that of human populations. Sound animal modeling is within our grasp to stimulate and support a mechanistic research front relevant to the immunological problems that accompany acute pediatric malnutrition.

THE RELEVANCE OF NUTRITIONAL STATUS AND HISTOPATHOLOGICAL FINDINGS ON THE INFECTIOUS PROCESS OF BALB/C MICE INOCULATED WITH Lacazia loboi.

The aim of this study was to evaluate the effects of the protein-calorie malnutrition in BALB/c isogenic mice infected with Lacazia loboi, employing nutritional and histopathological parameters. Four groups were composed: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. Once malnutrition had been imposed, the animals were inoculated intradermally in the footpad and after four months, were sacrificed for the excision of the footpad, liver and spleen. The infection did not exert great influence on the body weight of the mice. The weight of the liver and spleen showed reduction in the undernourished groups when compared to the nourished groups. The macroscopic lesions, viability index and total number of fungi found in the footpads of the infected mice were increased in G3 when compared to G1. Regarding the histopathological analysis of the footpad, a global cellularity increase in the composition of the granuloma was observed in G3 when compared to G1, with large numbers of macrophages and multinucleated giant cells, discrete numbers of lymphocytes were present in G3 and an increase was observed in G1. The results suggest that there is considerable interaction between Jorge Lobo's disease and nutrition.

THE RELEVANCE OF NUTRITIONAL STATUS AND HISTOPATHOLOGICAL FINDINGS ON THE INFECTIOUS PROCESS OF BALB/C MICE INOCULATED WITH Lacazia loboi / A relevância do estado nutricional e alterações histopatológicas no processo infeccioso de camundongos BALB/c inoculados com Lacazia loboi

SUMMARY The aim of this study was to evaluate the effects of the protein-calorie malnutrition in BALB/c isogenic mice infected with Lacazia loboi, employing nutritional and histopathological parameters. Four groups were composed: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. Once malnutrition had been imposed, the animals were inoculated intradermally in the footpad and after four months, were sacrificed for the excision of the footpad, liver and spleen. The infection did not exert great influence on the body weight of the mice. The weight of the liver and spleen showed reduction in the undernourished groups when compared to the nourished groups. The macroscopic lesions, viability index and total number of fungi found in the footpads of the infected mice were increased in G3 when compared to G1. Regarding the histopathological analysis of the footpad, a global cellularity increase in the composition of the granuloma was observed in G3 when compared to G1, with large numbers of macrophages and multinucleated giant cells, discrete numbers of lymphocytes were present in G3 and an increase was observed in G1. The results suggest that there is considerable interaction between Jorge Lobo's disease and nutrition.

RESUMO O objetivo do estudo foi avaliar os efeitos da desnutrição protéico-calórica em camundongos isogênicos da linhagem BALB/c inoculados com Lacazia loboi, empregando parâmetros nutricionais e histopatológicos. Foram constituídos quatro grupos: G1- inoculados com restrição dietética; G2- não inoculados com restrição dietética; G3- inoculados sem restrição dietética; G4- não inoculados sem restrição dietética. Após instalada a desnutrição, os animais foram inoculados via intradérmica no coxim plantar e após quatro meses foram sacrificados para remoção do coxim plantar, fígado e baço. A infecção não exerceu grande influência no peso corporal dos camundongos. O peso do fígado e baço apresentou redução nos grupos desnutridos em comparação aos grupos nutridos. A lesão macroscópica, a viabilidade e o número total de fungos dos coxins plantares dos camundongos inoculados revelaram aumento no G3 quando comparado com o G1. Em relação à análise histopatológica dos coxins plantares observou-se aumento da celularidade global na composição do granuloma no G3 em relação ao G1, com grande número de macrófagos e células gigantes multinucleadas, discretos números de linfócitos estavam presentes em G3 e aumentados no G1. Os resultados sugerem que existe grande interação entre nutrição e doença de Jorge Lobo.

Midupper Arm Circumference Outperforms Weight-Based Measures of Nutritional Status in Children with Diarrhea.

BACKGROUND: Undernutrition contributes to 45% of all deaths in children <5 y of age worldwide, with a large proportion of those deaths caused by diarrhea. However, no validated tools exist for assessing undernutrition in children with diarrhea and possible dehydration. OBJECTIVE: This study assessed the validity of different measures of undernutrition in children with diarrhea. METHODS: A prospective cohort study was conducted at an urban hospital in Bangladesh. Children <60 mo of age presenting to the hospital rehydration unit with acute diarrhea were eligible for enrollment. Study staff randomly selected 1196 children for screening, of which 1025 were eligible, 850 were enrolled, and 721 had complete data for analysis. Anthropometric measurements, including weight-for-age z score (WAZ), weight-for-length z score (WLZ), midupper arm circumference (MUAC), and midupper arm circumference z score (MUACZ), were calculated pre- and posthydration in all patients. Measurements were evaluated for their ability to correctly identify undernutrition in children with varying degrees of dehydration. RESULTS: Of the 721 patients with full data for analysis, the median percent dehydration was 4%. Of the 4 measures evaluated, MUAC and MUACZ demonstrated 92-94% agreement pre- and posthydration compared with 69-76% for WAZ and WLZ. Although each 1% change in hydration status was found to change weight-for-age by 0.0895 z scores and weight-for-length by 0.1304 z scores, MUAC and MUACZ were not significantly affected by dehydration status. Weight-based measures misclassified 12% of children with severe underweight and 14% with severe acute malnutrition (SAM) compared with only 1-2% for MUAC and MUACZ. CONCLUSIONS: MUAC and MUACZ were the most accurate predictors of undernutrition in children with diarrhea. WAZ and WLZ were significantly affected by dehydration status, leading to the misdiagnosis of many patients on arrival with severe underweight and SAM. This trial was registered at clinicaltrials.gov as NCT02007733.

Leucine supplementation improves acquired growth hormone resistance in rats with protein-energy malnutrition.

BACKGROUND: Protein-energy malnutrition (PEM) can lead to growth hormone (GH) resistance. Leucine supplementation diets have been shown to increase protein synthesis in muscles. Our study aimed at investigating if long-term leucine supplementation could modulate GH-insulin-like growth factor (IGF)-1 system function and mammalian target of rapamycin (mTOR)-related signal transduction in skeletal muscles in a rat model of severe malnutrition. METHODOLOGY/PRINCIPAL FINDINGS: Male Sprague-Dawley rats (n = 50; weight, 302 ± 5 g) were divided into 5 treatment groups, including 2 control groups (a normal control group that was fed chow and ad libitum water [CON, n = 10] and a malnourished control group [MC, n = 10] that was fed a 50% chow diet). After undergoing a weight loss stage for 4 weeks, rats received either the chow diet (MC-CON, n = 10), the chow diet supplemented with low-dose leucine (MC-L, n = 10), or the chow diet supplemented with high-dose leucine (MC-H, n = 10) for 2 weeks. The muscle masses of the gastrocnemius, soleus, and extensor digitorum longus were significantly reduced in the MC group. Re-feeding increased muscle mass, especially in the MC-L and MC-H groups. In the MC group, serum IGF-1, IGF-binding protein (IGFBP)-3, and hepatic growth hormone receptor (GHR) levels were significantly decreased and phosphorylation of the downstream anabolic signaling effectors protein kinase B (Akt), mTOR, and ribosomal protein S6 kinase 1 (S6K1) were significantly lower than in other groups. However, serum IGF-1 and IGF binding protein (IGFBP)-3 concentrations and hepatic growth hormone receptor (GHR) levels were significantly higher in the MC-L and MC-H groups than in the MC-CON group, and serum IGFBP-1 levels was significantly reduced in the MC-L and MC-H groups. These changes were consistent with those observed for hepatic mRNA expression levels. Phosphorylation of the downstream anabolic signaling effectors Akt, mTOR, and S6K1 were also significantly higher in the MC-L and MC-H groups than in the MC-CON group. CONCLUSION/SIGNIFICANCE: Our data are the first to demonstrate that long-term supplementation with leucine improved acquired growth hormone resistance in rats with protein-energy malnutrition. Leucine might promote skeletal muscle protein synthesis by regulating downstream anabolic signaling transduction.

A simple protein-energy wasting score predicts survival in maintenance hemodialysis patients.

OBJECTIVE: Nutritional status is a powerful predictor of survival in maintenance hemodialysis patients but remains challenging to assess. We defined a new Protein Energy Wasting (PEW) score based on the nomenclature proposed by the International Society of Renal Nutrition and Metabolism in 2008. DESIGN AND METHODS: This score, graded from 0 (worse) to 4 (best) was derived from 4 body nutrition compartments: serum albumin, body mass index, a normalized serum creatinine value, and protein intake as assessed by nPNA. SUBJECTS: We applied this score to 1443 patients from the ARNOS prospective dialysis cohort and provide survival data from 2005 until 2008. MAIN OUTCOME MEASURE: Patients survival at 3.5 year. RESULTS: Survival ranged from 84%-69% according to the protein-energy wasting score. There was a clear-cut reduction in survival (5%-7%; P < 0.01) for each unit decrement in the score grade. There was a 99% survival at 1 year for patients with the score of 4. In addition, the 6-month variation of this PEW score also strongly predicted patients' survival (P < 0.01). CONCLUSION: A new simple and easy-to-get PEW score predicts survival in maintenance hemodialysis patients. Furthermore, increase of this nutritional score over time also indicates survival improvement, and may help to better identify subgroups of patients with a high mortality rate, in which nutrition support should be enforced.

Probiotics protect the intestinal wall of morphological changes caused by malnutrition.

This study sought to morphometrically analyze the jejunal wall of protein-malnourished rats administered a probiotic supplement. The sample consisted of recently weaned Wistar rats (Rattus norvegicus) distributed among four groups: animals given a commercial diet (G1, n = 4); animals given the same ration as G1 plus a probiotic supplement (G2, n = 4); animals given a 4% protein diet (G3, n = 4); and animals given the same ration as G3 plus a probiotic supplement (G4, n = 4). After 12 weeks, part of the jejunum was harvested and subjected to routine histological processing. Transverse sections with a thickness of 3 µm were stained with HE, and histochemical techniques were used to assay for glycoconjugates, including staining with periodic acid-Schiff (PAS) + diastase, Alcian Blue (AB) solution at pH 2.5, and Alcian Blue solution at pH 1.0. Morphometric analysis of the bowel wall showed that the probiotic culture used in this study induced hypertrophy of several layers of the jejunal wall in well-nourished animals and reduced the bowel wall atrophy usually observed in protein-malnourished animals. Neither malnutrition nor the use of probiotics altered the relationship between the number of goblet cells and the number of enterocytes.

Malnutrition and retinal vascular caliber in the elderly: the POLA study.

PURPOSE: The pathway linking late-life malnutrition to greater risk of cardiovascular disease is unclear. Microcirulatory changes assessed by retinal vascular caliber have been linked with increased risk of stroke and coronary heart disease. The purpose of this study was to examine whether retinal vascular calibers are associated with malnutrition in elderly subjects free of cardiovascular diseases. METHODS: This was a cross-sectional analysis of a community-dwelling cohort comprising 1145 individuals aged 60 years and older. Retinal vascular caliber was measured from fundus photographs using a semiautomated, standardized imaging software. Malnutrition was assessed using body mass index (BMI) < 18.5 kg/m(2) and biomarkers of protein malnutrition: plasma albumin and transthyretin. RESULTS: In a multivariate model controlling for cardiovascular risk factors, retinal venular caliber was related to BMI (P = 0.0002) with an increased mean caliber for individuals with obesity and for those with low BMI. After multivariate adjustment for age, sex, hypertension, smoking, high-density lipoprotein (HDL) cholesterol, glomerular filtration rate and BMI, lower levels of albumin or transthyretin were associated with larger retinal venular caliber (P = 0.026 and P = 0.0018, respectively), that remain significant when adjusting for CRP (P = 0.040 and P = 0.0060, respectively) or orosomucoid (P = 0.034 and P = 0.0020, respectively). The relationships between retinal arteriolar caliber and BMI, albumin and transthyretin did not reach significance (P = 0.14, P = 0.12, and P = 0.15, respectively). CONCLUSIONS: Protein malnutrition was identified as an additional factor associated with retinal venular dilatation beyond inflammation. This suggests that early microvascular changes may be one of the underlying mechanisms of increased risk of cardiovascular disease observed in elderly subjects suffering from malnutrition.

Fundamental determinants of protein requirements in the ICU.

PURPOSE OF REVIEW: Currently, feeding the ICU patient is highly discussed. Energy feeding has been the topic of randomized studies, but protein feeding has not. Study results are contradictory on early feeding; however, little is known about early protein requirement. What is this protein requirement based on, therefore what are the fundamental determinants? RECENT FINDINGS: Recent studies have addressed the importance of protein feeding and/or muscle (protein) wasting in critically ill patients. Targeted feeding has been shown to improve protein balance in one study, and infection rate in one study. Low muscle mass that is already present during ICU admission has been shown to be related to higher mortality, in two studies. Four studies have related muscle wasting to (protein) feeding strategies with very diverse results: Two small studies have reported no advantage [n = 15, computed tomography] or negative impact (n = 62, ultrasound, 50% sepsis patients) of protein on muscle wasting. Two studies, one small (n = 33, computed tomography) and one very large (n = 1372, Subjective Global Assessment), have reported a positive impact of (early) feeding on muscle wasting. SUMMARY: Fundamental to adequate protein feeding in critically ill patients, at least 1.2 g protein/kg per day, is targeted energy feeding using indirect calorimetry. The level of protein requirement is related to fat free mass or muscle mass, which makes sex and BMI also relevant. Targeted early protein feeding is found to improve short-term outcome, reduction of muscle wasting and hospital mortality. Long-term outcome of protein feeding has not been studied. However, targeted protein feeding may be harmful in sepsis patients. Up to now, we lack biomarkers that provide caregivers with an instrument to increase protein feeding up to the individual protein requirement of the critically ill patient.

Postnatal protein malnutrition induces neurochemical alterations leading to behavioral deficits in rats: prevention by selenium or zinc supplementation.

BACKGROUND/OBJECTIVES: Protein malnutrition (PM) is a worldwide problem affecting brain development in a large number of children. The present study was aimed at studying the perturbations in antioxidant defense system resulting from protein deficiency and to evaluate the preventive effect of Se and Zn on cortex and cerebellum. METHODS: Well-fed (WF) and PM rats were fed on 16 and 5% protein diet, respectively. After 10 weeks, animals were supplemented with Se and Zn at a concentration of 0.15 and 227 mg/l in drinking water for 3 weeks. RESULTS: PM rats showed significant increase in lipid peroxidation, nitrite, and protein carbonyl levels. Reduction in the activity of antioxidant enzymes, thiol levels, GSH/GSSG ratio, and neurobehavioral deficits were observed in PM groups. Se and Zn supplementation reduced the levels of lipid peroxidation, nitrite, and protein carbonyl and restored the activity of antioxidant enzymes and thiol levels in the cortex and cerebellum of PM rats along with neurobehavioral deficits. DISCUSSION: The study showed that Se and Zn supplementation might be beneficial in preventing biochemical alterations and neurobehavioral deficits in PM children.

Acute effects of rotavirus and malnutrition on intestinal barrier function in neonatal piglets.

AIM: To investigate the effect of protein-energy malnutrition on intestinal barrier function during rotavirus enteritis in a piglet model. METHODS: Newborn piglets were allotted at day 4 of age to the following treatments: (1) full-strength formula (FSF)/noninfected; (2) FSF/rotavirus infected; (3) half-strength formula (HSF)/noninfected; or (4) HSF/rotavirus infected. After one day of adjustment to the feeding rates, pigs were infected with rotavirus and acute effects on growth and diarrhea were monitored for 3 d and jejunal samples were collected for Ussing-chamber analyses. RESULTS: Piglets that were malnourished or infected had lower body weights on days 2 and 3 post-infection (P < 0.05). Three days post-infection, marked diarrhea and weight loss were accompanied by sharp reductions in villus height (59%) and lactase activity (91%) and increased crypt depth (21%) in infected compared with non-infected pigs (P < 0.05). Malnutrition also increased crypt depth (21%) compared to full-fed piglets. Villus:crypt ratio was reduced (67%) with viral infection. There was a trend for reduction in transepithelial electrical resistance with rotavirus infection and malnutrition (P = 0.1). (3)H-mannitol flux was significantly increased (50%; P < 0.001) in rotavirus-infected piglets compared to non-infected piglets, but there was no effect of nutritional status. Furthermore, rotavirus infection reduced localization of the tight junction protein, occludin, in the cell membrane and increased localization in the cytosol. CONCLUSION: Overall, malnutrition had no additive effects to rotavirus infection on intestinal barrier function at day 3 post-infection in a neonatal piglet model.

Effect of protein malnutrition on the metabolism and toxicity of cisplatin, 5-fluorouracil and mitomycin C in rat stomach.

This study investigated the effect of protein malnutrition on metabolism and toxicity of cisplatin (CP), 5-fluorouracil (FU) and mitomycin C (MMC) in rat stomach. Weanling male Wistar rats received a normal (24%) or low (2.5%) protein diet for 28 days and were allocated into: normally-fed control, protein-malnourished control (PM), 3 normally-fed drug-treated groups and 3 protein-malnourished drug-treated groups (PM-CP, PM-FU and PM-MMC). Cisplatin and MMC were injected intraperitoneally (8 mg/kg on day 26 and 1 mg/kg/day for 7 days, respectively). 5-Fluorouracil was given orally (50 mg/kg/day for 5 days). Compared with normally-fed counterparts, PM-CP rats exhibited higher glutathione S-transferase, aminopeptidase N and cysteine S-conjugate beta-lyase (CCBL) and lower gamma-glutamyltransferase activities, PM-FU rats exhibited decreased dihydropyrimidine dehydrogenase and cytochrome P450 1A1/2 activities and PM-MMC rats showed higher quinone reductase and depleted xanthine oxidase activities. Protein-malnourished drug-treated groups exhibited exacerbated gastrotoxicity, relative to normally-fed counterparts, manifested by lower mucus levels, higher permeability and histopathological deterioration, along with increased oxidative stress in PM-CP rats and exaggerated prostaglandin E2 production in PM-MMC rats. Conclusively, protein malnutrition alters CP, FU and MMC metabolism in rat stomach by enhancing CCBL pathway for CP activation, delaying FU elimination and activating two-electron reduction of MMC, potentiating their gastrotoxicity.