Diet enriched in saturated fatty acids induces liver oxidative stress and elicits inflammatory pathways prior to metabolic disruption in perinatal protein undernutrition.

The impact of diets high in saturated fatty acids in individuals who have undergone maternal protein restriction is not clear. Here, we tested the hypothesis that a saturated fatty acid-enriched hyperlipidic diet (HL) affects liver expression of genes of the redox balance and inflammatory pathway in postweaning rat offspring subjected to maternal protein restriction. Pregnant Wistar rats received either a control (C; 19% protein) or low protein (LP; 8% protein) diet during gestation and lactation. At weaning, pups received either C or HL diets up to 90 days of life. The LP+HL group showed an upregulation of transcription of peroxisome proliferator-activated receptor γ (+48%) and peroxisome proliferator-activated receptor γ coactivator α (+96%) compared with the LP+C group (P < .05), respectively. Similarly, gene expression of the markers of inflammation, nuclear factor-kappa B1 (+194%) and tumor necrosis factor-α (+192%), was enhanced (P < .05). Although other antioxidant enzymes were not modified in gene expression, catalase (CAT) was 66% higher in LP+HL compared with LP+C. In contrast, CAT protein content in the liver was 50% lower in LP groups compared with C, and superoxide dismutase 2 (SOD2) was twice as high in LP groups compared with C. Postweaning HL after maternal protein restriction induces hepatic metabolic adaptation characterized by enhanced oxidative stress, unbalanced expression in the antioxidant enzymes SOD1, SOD2 and CAT, and activation of inflammatory pathways but does not impact circulating markers of lipid metabolism and liver function.

C/EBP homologous protein deficiency enhances hematopoietic stem cell function via reducing ATF3/ROS-induced cell apoptosis.

Hematopoietic stem cells (HSCs) reside in a quiescent niche to reserve their capacity of self-renewal. Upon hematopoietic injuries, HSCs enter the cell cycle and encounter protein homeostasis problems caused by accumulation of misfolded proteins. However, the mechanism by which protein homeostasis influences HSC function and maintenance remains poorly understood. Here, we show that C/EBP homologous protein (CHOP), demonstrated previously to induces cell death upon unfolded protein response (UPR), plays an important role in HSCs regeneration. CHOP-/- mice showed normal hematopoietic stem and progenitor cell frequencies in steady state. However, when treated with 5-FU, CHOP deficiency resulted in higher survival rates, associated with an increased number of HSCs and reduced level of apoptosis. In serial competitive transplantation experiments, CHOP-/- HSCs showed a dramatic enhancement of repopulation ability and a reduction of protein aggresomes. Mechanistically, CHOP deletion causes reduced ATF3 expression and further leads to decreased protein aggregation and ROS. In addition, CHOP-/- HSCs exhibited an increased resistance to IR-induced DNA damage and improved HSCs homeostasis and function in telomere dysfunctional (G3Terc-/- ) mice. In summary, these findings disclose a new role of CHOP in the regulation of the HSCs function and homeostasis through reducing ATF3 and ROS signaling.

Effects of protein malnutrition on hematopoietic regulatory activity of bone marrow mesenchymal stem cells.

Protein malnutrition causes anemia and leukopenia as it reduces hematopoietic precursors and impairs the production of mediators that regulate hematopoiesis. Hematopoiesis occurs in distinct bone marrow niches that modulate the processes of differentiation, proliferation and self-renewal of hematopoietic stem cells (HSCs). Mesenchymal stem cells (MSCs) contribute to the biochemical composition of bone marrow niches by the secretion of several growth factors and cytokines, and they play an important role in the regulation of HSCs and hematopoietic progenitors. In this study, we investigated the effect of protein malnutrition on the hematopoietic regulatory function of MSCs. C57BL/6NTaq mice were divided into control and protein malnutrition groups, which received, respectively, a normal protein diet (12% casein) and a low protein diet (2% casein). The results showed that protein malnutrition altered the synthesis of SCF, TFG-ß, Angpt-1, CXCL-12, and G-CSF by MSCs. Additionally, MSCs from the protein malnutrition group were not able to maintain the lymphoid, granulocytic and megakaryocytic-erythroid differentiation capacity compared to the MSCs of the control group. In this way, the comprehension of the role of MSCs on the regulation of the hematopoietic cells, in protein malnutrition states, is for the first time showed. Therefore, we infer that hematopoietic alterations caused by protein malnutrition are due to multifactorial alterations and, at least in part, the MSCs' contribution to hematological impairment.

1H NMR metabolomic and transcriptomic analyses reveal urinary metabolites as biomarker candidates in response to protein undernutrition in adult rats.

Protein undernutrition contributes to the development of various diseases in broad generations. Urinary metabolites may serve as non-invasive biomarkers of protein undernutrition; however, this requires further investigation. We aimed to identify novel urinary metabolites as biomarker candidates responsive to protein undernutrition. Adult rats were fed control (CT; 14 % casein) or isoenergetic low-protein (LP; 5 % casein) diets for 4 weeks. 1H NMR metabolomics was applied to urine, plasma and liver samples to identify metabolites responsive to protein undernutrition. Liver samples were subjected to mRNA microarray and quantitative PCR analyses to elucidate the mechanisms causing fluctuations in identified metabolites. Urinary taurine levels were significantly lower in the LP group than in the CT group at week 1 and remained constant until week 4. Hepatic taurine level and gene expression level of cysteine dioxygenase type 1 were also significantly lower in the LP group than in the CT group. Urinary trimethylamine N-oxide (TMAO) levels were significantly higher in the LP group than in the CT group at week 2 and remained constant until week 4. Hepatic TMAO level and gene expression levels of flavin-containing mono-oxygenase 1 and 5 were also significantly higher in the LP group than in the CT group. In conclusion, urinary taurine and TMAO levels substantially responded to protein undernutrition. Furthermore, changes in hepatic levels of these metabolites and gene expressions associated with their metabolic pathways were also reflected in their fluctuating urinary levels. Thus, taurine and TMAO could act as non-invasive urinary biomarker candidates to detect protein undernutrition.

Unusual Late-onset Enteropathy in a Patient With Lipopolysaccharide-responsive Beige-like Anchor Protein Deficiency.

In recent years, monogenic causes of immune dysregulation syndromes, with variable phenotypes, have been documented. Mutations in the lipopolysaccharide-responsive beige-like anchor (LRBA) protein are associated with common variable immunodeficiency, autoimmunity, chronic enteropathy, and immune dysregulation disorders. The LRBA protein prevents degradation of cytotoxic T-lymphocyte antigen 4 (CTLA4) protein, thus inhibiting immune responses. Both LRBA and CTLA4 deficiencies usually present with immune dysregulation, mostly characterized by autoimmunity and lymphoproliferation. In this report, we describe a patient with an atypical clinical onset of LRBA deficiency and the patient's response to abatacept, a fusion protein-drug that mimics the action of CTLA4.

[Protein deficiency - a rare nutrient deficiency]. / Svårt att få brist på protein ­ för högt intag större risk - Lagom mängd mat ­ oavsett kosttyp ­ ger tillräckligt mycket.

There is a widespread myth that we have to be careful about what we eat so that we do not cause protein deficiency. We know today that it is virtually impossible to design a calorie-sufficient diet, whether it is based on meat, fish, eggs, various vegetarian diets or even unprocessed whole natural plant foods, which is lacking in protein and any of the amino acids. The body is capable of taking incomplete proteins and making them complete by utilizing the amino acid recycling mechanism. The majority of amino acids absorbed from the intestinal tract are derived from recycled body protein. Research shows that high levels of animal protein intake may significantly increase the risk of premature mortality from all causes, among them cardiovascular diseases, cancer and type 2 diabetes.

Differential expression of genes in fetal brain as a consequence of maternal protein deficiency and nematode infection.

Maternal dietary protein deficiency and gastrointestinal nematode infection during early pregnancy have negative impacts on both maternal placental gene expression and fetal growth in the mouse. Here we used next-generation RNA sequencing to test our hypothesis that maternal protein deficiency and/or nematode infection also alter the expression of genes in the developing fetal brain. Outbred pregnant CD1 mice were used in a 2×2 design with two levels of dietary protein (24% versus 6%) and two levels of infection (repeated sham versus Heligmosomoides bakeri beginning at gestation day 5). Pregnant dams were euthanized on gestation day 18 to harvest the whole fetal brain. Four fetal brains from each treatment group were analyzed using RNA Hi-Seq sequencing and the differential expression of genes was determined by the edgeR package using NetworkAnalyst. In response to maternal H. bakeri infection, 96 genes (88 up-regulated and eight down-regulated) were differentially expressed in the fetal brain. Differentially expressed genes were involved in metabolic processes, developmental processes and the immune system according to the PANTHER classification system. Among the important biological functions identified, several up-regulated genes have known neurological functions including neuro-development (Gdf15, Ing4), neural differentiation (miRNA let-7), synaptic plasticity (via suppression of NF-κß), neuro-inflammation (S100A8, S100A9) and glucose metabolism (Tnnt1, Atf3). However, in response to maternal protein deficiency, brain-specific serine protease (Prss22) was the only up-regulated gene and only one gene (Dynlt1a) responded to the interaction of maternal nematode infection and protein deficiency. In conclusion, maternal exposure to GI nematode infection from day 5 to 18 of pregnancy may influence developmental programming of the fetal brain.

Hematological alterations in protein malnutrition.

Protein malnutrition is one of the most serious nutritional problems worldwide, affecting 794 million people and costing up to $3.5 trillion annually in the global economy. Protein malnutrition primarily affects children, the elderly, and hospitalized patients. Different degrees of protein deficiency lead to a broad spectrum of signs and symptoms of protein malnutrition, especially in organs in which the hematopoietic system is characterized by a high rate of protein turnover and, consequently, a high rate of protein renewal and cellular proliferation. Here, the current scientific information about protein malnutrition and its effects on the hematopoietic process is reviewed. The production of hematopoietic cells is described, with special attention given to the hematopoietic microenvironment and the development of stem cells. Advances in the study of hematopoiesis in protein malnutrition are also summarized. Studies of protein malnutrition in vitro, in animal models, and in humans demonstrate several alterations that impair hematopoiesis, such as structural changes in the extracellular matrix, the hematopoietic stem cell niche, the spleen, the thymus, and bone marrow stromal cells; changes in mesenchymal and hematopoietic stem cells; increased autophagy; G0/G1 cell-cycle arrest of progenitor hematopoietic cells; and functional alterations in leukocytes. Structural and cellular changes of the hematopoietic microenvironment in protein malnutrition contribute to bone marrow atrophy and nonestablishment of hematopoietic stem cells, resulting in impaired homeostasis and an impaired immune response.

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.

Protein- and zinc-deficient diets modulate the murine microbiome and metabolic phenotype.

BACKGROUND: Environmental enteropathy, which is linked to undernutrition and chronic infections, affects the physical and mental growth of children in developing areas worldwide. Key to understanding how these factors combine to shape developmental outcomes is to first understand the effects of nutritional deficiencies on the mammalian system including the effect on the gut microbiota. OBJECTIVE: We dissected the nutritional components of environmental enteropathy by analyzing the specific metabolic and gut-microbiota changes that occur in weaned-mouse models of zinc or protein deficiency compared with well-nourished controls. DESIGN: With the use of a 1H nuclear magnetic resonance spectroscopy-based metabolic profiling approach with matching 16S microbiota analyses, the metabolic consequences and specific effects on the fecal microbiota of protein and zinc deficiency were probed independently in a murine model. RESULTS: We showed considerable shifts within the intestinal microbiota 14-24 d postweaning in mice that were maintained on a normal diet (including increases in Proteobacteria and striking decreases in Bacterioidetes). Although the zinc-deficient microbiota were comparable to the age-matched, well-nourished profile, the protein-restricted microbiota remained closer in composition to the weaned enterotype with retention of Bacteroidetes. Striking increases in Verrucomicrobia (predominantly Akkermansia muciniphila) were observed in both well-nourished and protein-deficient mice 14 d postweaning. We showed that protein malnutrition impaired growth and had major metabolic consequences (much more than with zinc deficiency) that included altered energy, polyamine, and purine and pyrimidine metabolism. Consistent with major changes in the gut microbiota, reductions in microbial proteolysis and increases in microbial dietary choline processing were observed. CONCLUSIONS: These findings are consistent with metabolic alterations that we previously observed in malnourished children. The results show that we can model the metabolic consequences of malnutrition in the mouse to help dissect relevant pathways involved in the effects of undernutrition and their contribution to environmental enteric dysfunction.

One carbon metabolism in pregnancy: Impact on maternal, fetal and neonatal health.

One carbon metabolism or methyl transfer, a crucial component of metabolism in all cells and tissues, supports the critical function of synthesis of purines, thymidylate and methylation via multiple methyl transferases driven by the ubiquitous methyl donor s-adenosylmethionine. Serine is the primary methyl donor to the one carbon pool. Intracellular folates and methionine metabolism are the critical components of one carbon transfer. Methionine metabolism requires vitamin B12, B6 as cofactors and is modulated by endocrine signals and is responsive to nutrient intake. Perturbations in one carbon transfer can have profound effects on cell proliferation, growth and function. Epidemiological studies in humans and experimental model have established a strong relationship between impaired fetal growth and the immediate and long term consequences to the health of the offspring. It is speculated that during development, maternal environmental and nutrient influences by their effects on one carbon transfer can impact the health of the mother, impair growth and reprogram metabolism of the fetus, and cause long term morbidity in the offspring. The potential for such effects is underscored by the unique responses in methionine metabolism in the human mother during pregnancy, the absence of transsulfuration activity in the fetus, ontogeny of methionine metabolism in the placenta and the unique metabolism of serine and glycine in the fetus. Dietary protein restriction in animals and marginal protein intake in humans causes characteristic changes in one carbon metabolism. The impact of perturbations in one carbon metabolism on the health of the mother during pregnancy, on fetal growth and the neonate are discussed and their possible mechanism explored.

Perinatal low-protein diet alters brainstem antioxidant metabolism in adult offspring.

BACKGROUND AND OBJECTIVES: Studies in humans and animal models have established a close relationship between early environment insult and subsequent risk of development of non-communicable diseases, including the cardiovascular. Whereas experimental evidences highlight the early undernutrition and the late cardiovascular disease relation, the central mechanisms linking the two remain unknown. Owing to the oxidative balance influence in several pathologies, the aim of the present study was to evaluate the effects of maternal undernutrition (i.e. a low-protein (LP) diet) on oxidative balance in the brainstem. METHODS AND RESULTS: Male rats from mothers fed with an LP diet (8% casein) throughout the perinatal period (i.e. gestation and lactation) showed 10× higher lipid peroxidation levels than animals treated with normoprotein (17% casein) at 100 days of age. In addition, we observed the following reductions in enzymatic activities: superoxide dismutase, 16%; catalase, 30%; glutathione peroxidase, 34%; glutathione-S-transferase, 51%; glutathione reductase, 23%; glucose-6-phosphate dehydrogenase, 31%; and in non-enzymatic glutathione system, 46%. DISCUSSION: This study is the first to focus on the role of maternal LP nutrition in oxidative balance in a central nervous system structure responsible for cardiovascular control in adult rats. Our data observed changes in oxidative balance in the offspring, therefore, bring a new concept related to early undernutrition and can help in the development of a new clinical strategy to combat the effects of nutritional insult. Wherein the central oxidative imbalance is a feasible mechanism underlying the hypertension risk in adulthood triggered by maternal LP diet.

FGF21 is not required for glucose homeostasis, ketosis or tumour suppression associated with ketogenic diets in mice.

AIMS/HYPOTHESIS: Ketogenic diets (KDs) have increasingly gained attention as effective means for weight loss and potential adjunctive treatment of cancer. The metabolic benefits of KDs are regularly ascribed to enhanced hepatic secretion of fibroblast growth factor 21 (FGF21) and its systemic effects on fatty-acid oxidation, energy expenditure (EE) and body weight. Ambiguous data from Fgf21-knockout animal strains and low FGF21 concentrations reported in humans with ketosis have nevertheless cast doubt regarding the endogenous function of FGF21. We here aimed to elucidate the causal role of FGF21 in mediating the therapeutic benefits of KDs on metabolism and cancer. METHODS: We established a dietary model of increased vs decreased FGF21 by feeding C57BL/6J mice with KDs, either depleted of protein or enriched with protein. We furthermore used wild-type and Fgf21-knockout mice that were subjected to the respective diets, and monitored energy and glucose homeostasis as well as tumour growth after transplantation of Lewis lung carcinoma cells. RESULTS: Hepatic and circulating, but not adipose tissue, FGF21 levels were profoundly increased by protein starvation, independent of the state of ketosis. We demonstrate that endogenous FGF21 is not essential for the maintenance of normoglycaemia upon protein and carbohydrate starvation and is therefore not needed for the effects of KDs on EE. Furthermore, the tumour-suppressing effects of KDs were independent of FGF21 and, rather, driven by concomitant protein and carbohydrate starvation. CONCLUSIONS/INTERPRETATION: Our data indicate that the multiple systemic effects of KD exposure in mice, previously ascribed to increased FGF21 secretion, are rather a consequence of protein malnutrition.

Protein deficiency and intestinal nematode infection in pregnant mice differentially impact fetal growth through specific stress hormones, growth factors, and cytokines.

BACKGROUND: Protein deficiency (PD) and intestinal nematode infections commonly co-occur during pregnancy and impair fetal growth, but the complex network of signals has not been explored. OBJECTIVE: Our objective was to assess those stress hormones, growth factors, and cytokines affected by maternal PD and nematode infection and associated with fetal growth. METHODS: Using a 2 × 2 factorial design, CD-1 mice, fed protein-sufficient (PS; 24%) or protein-deficient (PD; 6%) isoenergetic diets, were either uninfected or infected every 5 d with Heligmosomoides bakeri, beginning on gestational day (GD) 5. Biomarker concentrations were measured on GD 18 in maternal serum (m), fetal serum (f), and amniotic fluid (af) by using Luminex. RESULTS: Maternal PD lowered fetal body mass (PS/uninfected 1.25 ± 0.02 g, PS/infected 1.19 ± 0.02 g vs. PD/uninfected 1.11 ± 0.02 g, PD/infected 0.97 ± 0.02 g; P = 0.02), fetal lung (P = 0.005), and liver (P = 0.003) but not brain mass, whereas maternal infection lowered fetal length (PS/uninfected 2.28 ± 0.02 cm, PD/uninfected 2.27 ± 0.03 cm vs. PS/infected 2.21 ± 0.03 cm, PD/infected 2.11 ± 0.02 cm; P = 0.05) and kidney mass (P = 0.04). PD elevated stress hormones (m-adrenocortiotropic hormone, f-corticosterone, af-corticosterone) and reduced insulin-like growth factor 1 in all compartments (P ≤ 0.01), but these were unassociated with fetal mass or length. Fetal mass was positively associated with f-leptin (R(2) = 0.71, P = 0.0001) and negatively with fetal cytokines [tumor necrosis factor-α: R(2) = 0.62, P = 0.001; interleukin-4 (IL-4): R(2) = 0.63, P = 0.0004]. In contrast, maternal infection lowered f-prolactin (P = 0.02) that was positively associated with fetal length (R(2) = 0.43; P = 0.03); no other biomarker was affected by infection. Regression analyses showed associations between organ growth, cytokines, and growth factors: 1) thymus, spleen, heart, and brain with m-IL-10; 2) brain and kidney with f-vascular endothelial growth factor, af-monocyte chemotactic protein 1, af-interferon-γ, and af-eotaxin; and 3) liver and lung with f-leptin and af-corticosterone (all P ≤ 0.02). CONCLUSIONS: PD and nematode infection impaired fetal mass and linear growth, respectively. Fetal mass, length, and individual organ masses were regulated by different hormones, growth factors, and cytokines.

[Controversies around diet proteins]. / Kontrowersje wokól bialek diety.

Critical theories regarding proteins of anima origin are still and still popularized, though they are ungrounded from scientific point of view. Predominance of soya proteins over the animal ones in relation to their influence on calcium metabolism, bone break risk or risk of osteoporosis morbidity has not been confirmed in any honest, reliable research experiment. Statement, that sulphur amino acids influence disadvantageously on calcium metabolism of human organism and bone status, is completely groundless, the more so as presence of sulphur amino acids in diet (animal proteins are their best source) is the condition of endogenic synthesis of glutathione, the key antioxidant of the organism, and taurine stimulating brain functioning. Deficiency of proteins in the diet produce weakness of intellectual effectiveness and immune response. There is no doubt that limitation of consumption of animal proteins of standard value is not good for health.

Folic acid and protein content in maternal diet and postnatal high-fat feeding affect the tissue levels of iron, zinc, and copper in the rat.

Although maternal, fetal, and placental mechanisms compensate for disturbances in the fetal environment, any nutritional inadequacies present during pregnancy may affect fetal metabolism, and their consequences may appear in later life. The aim of the present study is to investigate the influence of maternal diet during gestation on Fe, Zn, and Cu levels in the livers and kidneys of adult rats. The study was carried out on the offspring (n = 48) of mothers fed either a protein-balanced or a protein-restricted diet (18% vs. 9% casein) during pregnancy, with or without folic acid supplementation (0.005- vs. 0.002-g folic acid/kg diet). At 10 weeks of age, the offspring of each maternal group were randomly assigned to groups fed either the AIN-93G diet or a high-fat diet for 6 weeks, until the end of the experiment. The levels of Fe, Zn, and Cu in the livers and kidneys were determined by the F-AAS method. It was found that postnatal exposure to the high-fat diet was associated with increased hepatic Fe levels (p < 0.001), and with decreased liver Zn and Cu contents (p < 0.01 and p < 0.05, respectively), as well as with decreased renal Cu contents (p < 0.001). Moreover, the offspring's tissue mineral levels were also affected by protein and folic acid content in the maternal diet. Both prenatal protein restriction and folic acid supplementation increased the liver Zn content (p < 0.05) and the kidney Zn content (p < 0.001; p < 0.05, respectively), while folic acid supplementation resulted in a reduction in renal Cu level (p < 0.05). Summarizing, the results of this study show that maternal dietary folic acid and protein intake during pregnancy, as well as the type of postweaning diet, affect Fe, Zn, and Cu levels in the offspring of the rat. However, the mechanisms responsible for this phenomenon are unclear, and warrant further investigation.

Correlation of salivary and serum IgG, IgA levels with total protein in oral submucous fibrosis.

Oral submucous fibrosis (OSMF) is a disabling, potentially malignant condition of the oral cavity. The aetiology of OSMF is multifactorial but remains obscure. Although arecanut is considered to be the most important causative agent, responses observed in individuals using arecanut vary in relation to quantity and duration. It is considered that an immunological process is responsible for the pathogenesis of disease. We correlated salivary immunoglobulin A (IgA), salivary immunoglobulin G (IgG) and serum immunoglobulin A (IgA), serum immunoglobulin G (IgG), levels by turbidometric immunoassay. We estimated the levels of total serum protein (TSP) and haemoglobin (Hb) to determine the role of nutritional deficiency. The study population comprised 30 cases of OSMF and 10 controls. Five milliliters of blood and 2 ml of saliva were collected. Quantitative analysis of serum and salivary IgG, IgA was done by turbidometric immunoassay. TSP and Hb were estimated by Biuret and cyanmethaemoglobin methods, respectively. All patients showed significant (P < 0.01) increase in serum and salivary IgG, IgA levels as compared to controls. TSP patients showed significant (P < 0.01) decrease as compared to controls. Results of Hb in patients were not significant. The estimation of immunoglobulin levels is important to support the concept of autoimmune basis. Estimation of TSP and Hb suggests that nutrition has a definite role in OSMF.

Experimental model considerations for the study of protein-energy malnutrition co-existing with ischemic brain injury.

Protein-energy malnutrition (PEM) affects ~16% of patients at admission for stroke. We previously modeled this in a gerbil global cerebral ischemia model and found that PEM impairs functional outcome and influences mechanisms of ischemic brain injury and recovery. Since this model is no longer reliable, we investigated the utility of the rat 2-vessel occlusion (2-VO) with hypotension model of global ischemia for further study of this clinical problem. Male, Sprague-Dawley rats were exposed to either control diet (18% protein) or PEM induced by feeding a low protein diet (2% protein) for 7d prior to either global ischemia or sham surgery. PEM did not significantly alter the hippocampal CA1 neuron death (p = 0.195 by 2-factor ANOVA) or the increase in dendritic injury caused by exposure to global ischemia. Unexpectedly, however, a strong trend was evident for PEM to decrease the consistency of hippocampal damage, as shown by an increased incidence of unilateral or no hippocampal damage (p=0.069 by chi-square analysis). Although PEM caused significant changes to baseline arterial blood pH, pO(2), pCO(2), and fasting glucose (p<0.05), none of these variables (nor hematocrit) correlated significantly with CA1 cell counts in the malnourished group exposed to 2-VO (p>0.269). Intra-ischemic tympanic temperature and blood pressure were strictly and equally controlled between ischemic groups. We conclude that co-existing PEM confounded the consistency of hippocampal injury in the 2-VO model. Although the mechanisms responsible were not identified, this model of brain ischemia should not be used for studying this co-morbidity factor.

Protein-energy malnutrition alters thermoregulatory homeostasis and the response to brain ischemia.

Co-existing protein-energy malnutrition (PEM), characterized by deficits in both protein and energy status, impairs functional outcome following global ischemia and has been associated with increased reactive gliosis. Since temperature is a key determinant of brain damage following an ischemic insult, the objective was to investigate whether alterations in post-ischemic temperature regulation contribute to PEM-induced reactive gliosis following ischemia. Male Sprague-Dawley rats (190-280 g) were assigned to either control diet (18% protein) or PEM induced by feeding a low protein diet (2% protein) for 7 days prior to either global ischemia or sham surgery. There was a rapid disruption in thermoregulatory function in rats fed the low protein diet as assessed by continuous recording of core temperature with bio-electrical sensor transmitters. Both daily temperature fluctuation and mean temperature increased within the first 24 hours, and these remained significantly elevated throughout the 7 day pre-ischemic period (p < 0.027). In the immediate post-surgical period, PEM decreased body temperature to a greater extent than that in well-nourished controls (p = 0.003). The increase in daily temperature fluctuation caused by PEM persisted throughout the 7 day post-surgical period (p < 0.001), and this interacted with the effects of global ischemia on days 8 (p = 0.018) and 11 (p = 0.021). The astrocytic and microglial responses induced at 7 days after global ischemia were not influenced by PEM, but this preliminary analysis needs to be confirmed with a more reliable global ischemia model. In conclusion, exposure to a low protein diet rapidly impairs the ability to maintain thermoregulatory homeostasis, and the resultant PEM also diminishes the ability to thermoregulate in response to a challenge. Since temperature regulation is a key determinant of brain injury following ischemia, these findings suggest that the pathophysiology of brain injury could be altered in stroke victims with coexisting PEM.