Dietary Protein Intake and Transition between Frailty States in Octogenarians Living in New Zealand.

Adequate nutritional status may influence progression to frailty. The purpose of this study is to determine the prevalence of frailty and examine the relationship between dietary protein intake and the transition between frailty states and mortality in advanced age. We used data from a longitudinal cohort study of Maori (80-90 years) and non-Maori (85 years). Dietary assessments (24-h multiple pass dietary recalls) were completed at the second year of follow-up (wave 2 and forms the baseline in this study). Frailty was defined using the Fried Frailty criteria. Multi-state modelling examined the association of protein intake and transitions between frailty states and death over four years. Over three quarters of participants were pre-frail or frail at baseline (62% and 16%, respectively). Those who were frail had a higher co-morbidity (p < 0.05), where frailty state changed, 44% showed a worsening of frailty status (robust → pre-frail or pre-frail → frail). Those with higher protein intake (g/kg body weight/day) were less likely to transition from robust to pre-frail [Hazard Ratio (95% Confidence Interval): 0.28 (0.08-0.91)] but also from pre-frail to robust [0.24 (0.06-0.93)]. Increased protein intake was associated with lower risk of transitioning from pre-frailty to death [0.19 (0.04-0.80)], and this association was moderated by energy intake [0.22 (0.03-1.71)]. Higher protein intake in this sample of octogenarians was associated with both better and worse outcomes.

Protein restriction during puberty alters nutritional parameters and affects ovarian and uterine histomorphometry in adulthood in rats.

In a large part of the population inefficient ingestion of proteins, whether for cultural, aesthetic or economic reasons, is a global concern. Low-protein diets can cause severe functional complications, mainly during the development and maturation of organs and systems, including the female reproductive system. The present study investigated the effect of nutritional protein restriction during puberty on the oestrous cycle and expression of sex steroid receptors (AR, ERα e ERß) in ovarian and uterine tissues of adult rats. Protein restriction promoted lower body weight gain, feed efficiency and higher caloric intake. There was an increase in the oestrus phase arrest without changing the total length of the oestrous cycle. The consumption of low-protein diet also reduced the thickness of the uterine endometrium (uterine epithelium and endometrial stroma) in addition to increasing the number of primary and atretic follicles in the ovaries. Furthermore, the low-protein diet reduced the levels of androgen receptor (AR) and increased the oestrogen receptor ß (ERß) in the ovary, while no significant changes were observed in the uterus. Our study reinforces the importance of adequate protein intake during puberty, since physiological changes in this developmental period interfere with the histomorphometry of the ovaries and uteri, possibly resulting in impaired folliculogenesis and fertility in the reproductive period.

Taurine treatment reverses protein malnutrition-induced endothelial dysfunction of the pancreatic vasculature: The role of hydrogen sulfide.

BACKGROUND: Protein malnutrition in childhood predisposes individuals to vascular and pancreatic endocrine dysfunction, thus increasing the risk of diabetes and hypertension. Because taurine may reduce cardiometabolic risk, we hypothesized that taurine treatment has a beneficial effect on the pancreatic vasculature during protein restriction. METHODS AND RESULTS: Weaned mice were fed a normal or a low-protein diet and were treated with or without taurine for 3 months. The lieno-pancreatic artery (LPA) from low-protein diet-treated mice exhibited impaired endothelium-dependent relaxation to acetylcholine that was associated with decreased endothelium-derived hyperpolarization (EDH), hydrogen sulfide (H2S) production, and H2S-synthesizing CBS expression and impaired vasorelaxation to an H2S-donor, NaHS. These changes were prevented by taurine treatment. We compared the effects of taurine with the effects of the direct vasodilator hydralazine and found that both normalized blood pressure and the endothelial vasodilator function of the LPA in the mice fed a protein-restricted diet. However, only taurine restored the CBS expression in the LPA and insulin secretion in response to high glucose. The LPA supplies the pancreas and shares morphometry with the mesenteric resistance artery (MRA). However, in the MRA, low-protein diet-induced endothelial dysfunction is driven by impaired NOS-derived NO with no changes in H2S signaling. CONCLUSIONS: The results suggest that taurine protects against protein malnutrition-induced endothelial dysfunction in the LPA by upregulating the CBS-H2S pathway. Considering the importance of the pancreatic vasculature for endocrine islet activity, taurine may be a potential therapy for the vascular and metabolic dysfunction associated with malnutrition and comorbidities.

Negative effects of a low-quality protein diet on wound healing via modulation of the MMP2 activity in rats.

Protein malnutrition is largely associated with a delay or failure of the healing process. However, the effect of dietary protein quality on wound healing is largely unknown. This study aimed to reveal the effect of dietary protein quality on wound healing and elucidate the regulatory mechanisms in a rat model of full-thickness cutaneous wounds. Rats were fed a normal diet for a week, and then they were divided into three groups that were fed the following diet for the experimental period: casein diet, gluten diet and gluten + lysine diet. The gluten diet significantly decreased body weight and wound healing compared with the casein diet, but this effect was reversed by supplementation with lysine. The numbers of leukocytes were significantly higher in the skin of the gluten group than those in the casein group. The wounded skin tissues of the gluten group showed lower amounts of collagen deposition compared with that in the casein group. Our results also showed that both matrix metalloproteinase (MMP) 2 activity and MMP14 mRNA levels were significantly increased in the skin of the gluten group, compared with the casein group. In summary, this study suggests low-quality protein diets have negative effects on wound healing via modulation of MMP2 activity in rats.

Maternal protein malnutrition prolongs sickness behavior in male offspring.

Female rats were fed a normal or hypoproteic diet during the phases of gestation and lactation. The male offspring of these rats were grown to adulthood and used to study the effects of maternal protein malnutrition on progeny. The adult male rats were pretreated with either saline or LPS and subjected to behavioral tests 2 and 6 h after administration. Tumor necrosis factor (TNF-α), corticosterone and body temperature were the parameters used for assessment. Two hours after LPS administration, sickness behavior was developed in all the animals, regardless of maternal protein malnutrition. After 6 h of LPS administration, sickness behavior was more pronounced in the rats that had been subjected to maternal protein malnutrition. Only the rats with maternal protein malnutrition expressed an increase in the plasma levels of TNF-α and corticosterone. Maternal protein malnutrition prolongs sickness behaviors in offspring.

Club Cell Secretory Protein Deficiency Leads to Altered Lung Function.

RATIONALE: CC16 (club cell secretory protein-16), a member of the secretoglobin family, is one of the most abundant proteins in normal airway secretions and has been described as a serum biomarker for obstructive lung diseases. OBJECTIVES: To determine whether low CC16 is a marker for airway pathology or is implicated in the pathophysiology of progressive airway damage in these conditions. METHODS: Using human data from the birth cohort of the Tucson Children's Respiratory Study, we examined the relation of circulating CC16 levels with pulmonary function and responses to bronchial methacholine challenge from childhood up to age 32 years. In wild-type and CC16-/- mice, we set out to comprehensively examine pulmonary physiology, inflammation, and remodeling in the naive airway. MEASUREMENTS AND MAIN RESULTS: We observed that Tucson Children's Respiratory Study participants in the lowest tertile of serum CC16 had significant deficits in their lung function and enhanced airway hyperresponsiveness to methacholine challenge from 11 years throughout young adult life. Similarly, CC16-/- mice had significant deficits in lung function and enhanced airway hyperresponsiveness to methacholine as compared with wild-type mice, which were independent of inflammation and mucin production. As compared with wild-type mice, CC16-/- mice had significantly elevated gene expression of procollagen type I, procollagen type III, and α-smooth muscle actin, areas of pronounced collagen deposition and significantly enhanced smooth muscle thickness. CONCLUSIONS: Our findings support clinical observations by providing evidence that lack of CC16 in the lung results in dramatically altered pulmonary function and structural alterations consistent with enhanced remodeling.

Amino acid starvation-induced autophagy is involved in reduced subcutaneous fat deposition in weaning piglets derived from sows fed low-protein diet during gestation and lactation : Autophagy is involved in reduced fat deposition in maternal low-protein piglets.

PURPOSE: The study aimed to determine the effects of maternal low-protein (LP) diet on subcutaneous fat deposition of weaning piglets and the potential mechanism. METHODS: Sows were fed either a standard protein (SP, 15 and 18% crude protein) or a LP diet (50% protein levels of SP) throughout pregnancy and lactation. Subcutaneous fat and blood were sampled from male piglets at 28 days of age. Serum biochemical metabolites and hormone concentrations were detected with the enzymatic colorimetric methods. Serum-free amino acid (FAA) levels were measured by amino acid auto-analyzer. The mRNA and protein were measured by qRT-PCR and Western blot. RESULTS: Body weight, back fat thickness, triglycerides concentrations in subcutaneous fat tissue, and serum, as well as FFA concentrations were significantly reduced in LP piglets when compared with SP piglets. Further studies showed that mRNA and protein expression of acetyl-CoA carboxylase and fatty acid synthetase, two key enzymes of de novo lipogenesis, were significantly reduced in LP piglets, while mRNA expression and the lipolytic enzymes activities of lipolysis genes, adipose triglyceride lipase and hormone-sensitive lipase, were significantly increased. Furthermore, expression of autophagy-related gene 7 and autophagy maker gene microtubule-associated protein 1A/1B-light chain 3 (LC 3) as well as the conversion of LC3I to LC3II were significantly elevated, along with the expression of activating transcription factor-4 and eukaryotic translation initiation factor-2a. CONCLUSION: These results indicate that amino acid starvation-induced autophagy is involved in reduced subcutaneous fat deposition in maternal LP weaning piglets, demonstrating links between maternal protein restriction and offspring fat deposition.

Protein deficiency decreases stereotypic behavior frequency and prevalence and activity in the striped mouse Rhabdomys dilectus chakae.

Diverse motivational triggers, including diet, elicit stereotypic behavior. We investigated whether diets comprised of different protein levels but similar levels of energy were associated with the occurrence of locomotor stereotypies in the striped mouse Rhabdomys dilectus chakae. In a first experiment, 20 stereotypic and 20 non-stereotypic (10 subjects per sex and per group) juvenile (40 days old) subjects were placed on baseline (BP), high (HP) or low protein (LP) diet treatments (120 subjects in total). All subjects initially identified as stereotypic displayed stereotypic behavior in the BP and HP treatments on Days 60-63 and Days 80-83 compared to 35% and 12.5% of LP subjects, respectively. Moreover, LP subjects displayed lower levels of activity and stereotypic behavior than BP and HP subjects. Those identified as non-stereotypic never displayed stereotypy. In a second experiment, 48 individuals, bred and reared on LP and whose parents were stereotypic, were assigned to either HP (13 males, 12 females) or LP (12 males, 11 females) treatments at 50 days of age for 30 days. Stereotypy was three times less likely to occur in the LP than the HP treatment, and activity was greater in LP-HP individuals than LP-LP individuals. In both experiments, LP individuals had the lowest body mass. Striped mice adjusted their behaviors in response to dietary protein levels. Protein deficiency reduced activity and stereotypic behavior and prevalence, possibly related to an energy or neurological deficit.

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.

Protein malnutrition after weaning disrupts peripheral clock and daily insulin secretion in mice.

Changes in nutritional state may alter circadian rhythms through alterations in expression of clock genes. Protein deficiency has a profound effect on body metabolism, but the effect of this nutrient restriction after weaning on biological clock has not been explored. Thus, this study aims to investigate whether the protein restriction affects the daily oscillation in the behavior and metabolic rhythms, as well as expression of clock genes in peripheral tissues. Male C57BL/6 J mice, after weaning, were fed a normal-protein (NP) diet or a low-protein (LP) diet for 8 weeks. Mice fed an LP diet did not show difference in locomotor activity and energy expenditure, but the food intake was increased, with parallel increased expression of the orexigenic neuropeptide Npy and disruption of the anorexigenic Pomc oscillatory pattern in the hypothalamus. LP mice showed disruption in the daily rhythmic patterns of plasma glucose, triglycerides and insulin. Also, the rhythmic expression of clock genes in peripheral tissues and pancreatic islets was altered in LP mice. In pancreatic islets, the disruption of clock genes was followed by impairment of daily glucose-stimulated insulin secretion and the expression of genes involved in exocytosis. Pharmacological activation of REV-ERBα could not restore the insulin secretion in LP mice. The present study demonstrates that protein restriction, leading to development of malnutrition, alters the peripheral clock and metabolic outputs, suggesting that this nutrient provides important entraining cues to regulate the daily fluctuation of biological clock.

Quantitative changes in the V2 lateral visual cortex in developing rats with induced protein malnutrition

In this paper we have analyzed the quantitative changes in the lateral visual cortex V2 (V2L) from developing rats with induced isocaloric protein malnutrition that looks like Kwashiorkor condition, as well as the changes induced after refeeding. Using stereological techniques the cortical volume, numerical density and the absolute number of neurons and the average neuronal volume were estimated. The result obtained led us to the following conclusions: i) A significant enlargement in the ratio between brain weight and body weight was detected, disappearing after refeeding. ii) The volume of the cerebral cortex, and V2L was reduced. This was partially reversed by the refeeding at the level of the cerebral cortex, but there was not significant reversal in V2L. iii) The neuronal density was enlarged in V2L. Globally considered, this parameter was unchanged after refeeding. Nevertheless, in those animals refed from post-gestational age P0 the numerical density of neurons was significantly lower than in rats refed from post-gestational age P21. iv) The absolute number of neurons and their average volume was unchanged in V2L. Nevertheless, the average neuronal volume was significantly lower in rats with more than thirty days of postgestational age (>P30) in comparison with the rats with less than thirty days of post-gestational age (greater than or equal to P30). v). No differences regarding sex were observed at the level of the studied parameter

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Prenatal protein level impacts homing behavior in Long-Evans rat pups.

OBJECTIVE: This study assessed the effect of varying prenatal protein levels on the development of homing behavior in rat pups. METHODS: Long-Evans rats were fed one of the four isocaloric diets containing 6% (n = 7 litters), 12% (n = 9), 18% (n = 9), or 25% (n = 10) casein prior to mating and throughout pregnancy. At birth, litters were fostered to well-nourished control mothers fed a 25% casein diet during pregnancy, and an adequate protein diet (25% casein) was provided to weaning. On postnatal days 5, 7, 9, 11, and 13, homing behaviors, including activity levels, rate of successful returns to the nest quadrant and latencies to reach the nest over a 3-minute test period were recorded from two starting positions in the home cage. Adult body and brain weights were obtained at sacrifice (postnatal day 130 or 200). RESULTS: Growth was impaired in pups whose mothers were fed a 6% or, to a lesser extent, a 12% casein diet relative to pups whose mothers were fed the 18 and 25% casein diets. The 6 and 12% prenatal protein levels resulted in lower activity levels, with the greatest reduction on postnatal day 13. However, only the 6% pups had reduced success and higher latencies in reaching the nest quadrant when compared with pups from the three other nutrition groups. Latency in reaching the nest quadrant was significantly and negatively associated with adult brain weight. DISCUSSION: Home orientation is a sensitive measure of developmental deficits associated with variations in prenatal protein levels, including levels of protein deficiency that do not lead to overt growth failure.

Prenatal malnutrition and lead intake produce increased brain lipid peroxidation levels in newborn rats.

OBJECTIVES: Prenatal malnutrition (M) and lead intoxication (Pb) have adverse effects on neuronal development; one of the cellular mechanisms involved is a disruption of the pro- and anti-oxidant balance. In the developing brain, the vulnerability of neuronal membrane phospholipids is variable across the different brain areas. This study assesses the susceptibility of different brain regions to damage by quitar tissue oxidative stress and lead quitar concentrations to determine whether the combined effect of prenatal malnutrition (M) and lead (Pb) intoxication is worse than the effect of either of them individually. METHODS: M was induced with an isocaloric and hypoproteinic (6% casein) diet 4 weeks before pregnancy. Intoxication was produced with lead acetate in drinking water, from the first gestational day. Both the M and Pb models were continued until the day of birth. Four brain regions (hippocampus, cortex, striatum, and cerebellum) were dissected out to analyze the lipid peroxidation (LP) levels in four groups: normally nourished (C); normally nourished but intoxicated with lead (CPb); malnourished (M); and M intoxicated with lead (MPb). RESULTS: Dam body and brain weights were significantly reduced in the fourth gestational week in the MPb group. Their pups had significantly lower body weights than those in the C and CPb groups. The PbM group exhibited significant increases of lead concentration and LP in all areas evaluated. A potentiation effect of Pb and M on LP was found in the cerebellum. DISCUSSION: This study provides information on how environmental conditions (intoxication and malnutrition) during the intrauterine period could differentially affect the development of neuronal plasticity and, in consequence, alter adult brain functions such as learning and memory.

Effects of environmental enrichment on blood vessels in the optic tract of malnourished rats: A morphological and morphometric analysis.

OBJECTIVES: This study aimed to compare the effects of environmental enrichment in nourished (on a diet containing 16% protein) and malnourished (on a diet containing 6% protein) rats during the critical period of brain development, specifically focusing on the optic nerve. METHODS: By means of morphologic and morphometric assessment of the optic nerve, we analyzed the changes caused by diet and stimulation (environmental enrichment) on postnatal day 35, a time point ideal for such morphological analysis since developmental processes are considered complete at this age. RESULTS: Malnourished animals presented low body and brain weights and high body-to-brain weight ratio compared to well-nourished rats. Furthermore, malnourished animals showed morphological changes in the optic nerve such as edema and vacuolization characterized by increased interstitial space. The malnourished-stimulated group presented lesions characteristic of early protein malnutrition but were milder than lesions exhibited by malnourished-non-stimulated group. The morphometric analysis revealed no difference in glial cell density between groups, but there was significantly higher blood vessel density in the stimulated rats, independent of their nutritional condition. DISCUSSION: Our data indicate that protein malnutrition imposed during the critical period of brain development alters the cytoarchitecture of the optic nerve. In addition, we affirm that a 1-hour exposure to an enriched environment everyday was sufficient for tissue preservation in rats maintained on a low-protein diet. This protective effect might be related to angiogenesis, as confirmed by the increased vascular density observed in morphometric analyses.

Exposure to increased levels of estradiol during development can have long-term effects on the response to undernutrition in female rats.

OBJECTIVES: Undernutrition during development alters the expression of peptides that control energy expenditure and feeding behavior. Estrogens can also modulate these peptides. Here, we analyze whether the early postnatal administration of estradiol modulates the effects of undernutrition on neuroendocrine parameters in adult female Wistar rats. METHODS: Control rats were fed a control diet. Undernourished pups were submitted to a restricted diet with half of the undernourished rats receiving 0.4 mg/kg s.c. of estradiol benzoate (EB) from postnatal day (P) 6 until P13. Quantitative real-time polymerase chain reaction was performed to determine expression in the hypothalamus of agouti-related peptide (AgRP), proopiomelanocortin (POMC), neuropeptide Y (NPY), and cocaine- and amphetamine-regulated transcript. Plasma estradiol, testosterone, and adiponectin levels were measured by enzyme-linked immunosorbent assay. Total and acylated ghrelin levels were measured in plasma by radioimmunoassay. Insulin and leptin were measured by mulitplex immunoassays. RESULTS: Undernourishment decreased body weight, fat mass, plasma leptin and insulin levels, and hypothalamic POMC mRNA levels. An increase in orexigenic signals AgRP and NPY mRNA levels, and in plasma adiponectin levels were found in undernourished animals. Early postnatal treatment with EB to undernourished female rats reversed the effects of undernutrition on adult hypothalamic POMC mRNA levels. In addition, neonatal EB treatment to undernourished females significantly decreased adult plasma testosterone, estradiol, and acylated ghrelin levels. DISCUSSION: Our results suggest that increased estradiol during a critical period of development has the capacity to modulate the alterations that undernutrition produces on energy metabolism.

Effects of chronic malnourishment and aging on the ultrastructure of pyramidal cells of the dorsal hippocampus.

OBJECTIVES: Malnourishment (M) produces permanent alterations during the development of the CNS and might modify the aging process. In pyramidal neurons (PN) of the hippocampus, which are associated with learning and memory performance, few studies have focused on changes at the subcellular level under chronic malnutrition (ChM) in young (Y, 2 months old) and aged (A, 22 months old) rats. The present work evaluated the extent to which ChM disrupts organelles in PN of the dorsal hippocampus CA1 as compared to controls (C). METHODS: Ultrastructural analysis was performed at 8000× and 20 000× magnification: Nucleus eccentricity and somatic, cytoplasmic, and nuclear areas were measured; and in the PN perikaryon, density indices (number of organelles/cytoplasmic area) of Golgi membrane systems (GMS, normal, and swollen), mitochondria (normal and abnormal), and vacuolated organelles (lysosomes, lipofuscin granules, and multivesicular bodies (MVB)) were determined. RESULTS: The density of abnormal mitochondria, swollen GMS, and MVB increased significantly in the AChM group compared to the other groups. The amount of lipofuscin was significantly greater in the AChM than in the YChM groups - a sign of oxidative stress due to malnutrition and aging; however, in Y animals, ChM showed no effect on organelle density or the cytoplasmic area. An increased density of lysosomes as well as nucleus eccentricity was observed in the AC group, which also showed an increase in the cytoplasmic area. DISCUSSION: Malnutrition produces subcellular alterations in vulnerable hippocampal pyramidal cells, and these alterations may provide an explanation for the previously reported deficient performance of malnourished animals in a spatial memory task in which aging and malnutrition were shown to impede the maintenance of long-term memory.

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.

Protein and Older Persons.

An optimal protein intake is important for the preservation of muscle mass, functionality, and quality of life in older persons. In recent years, new recommendations regarding the optimal intake of protein in this population have been published. Based on the available scientific literature, 1.0 to 1.2 g protein/kg body weight (BW)/d are recommended in healthy older adults. In certain disease states, a daily protein intake of more than 1.2 g/kg BW may be required. The distribution of protein intake over the day, the amount per meal, and the amino acid profile of proteins are also discussed.

Enhanced mesenteric arterial responsiveness to angiotensin II is androgen receptor-dependent in prenatally protein-restricted adult female rat offspring.

Gestational protein restriction results in intrauterine growth restriction and hypertension in adult female growth-restricted rats. Enhanced vascular responsiveness to angiotensin II is observed, and blockade of the renin-angiotensin system abolishes hypertension in adult growth-restricted rats, suggesting that the renin-angiotensin system contributes to intrauterine growth restriction-induced hypertension. Moreover, growth-restricted adult rats have higher plasma testosterone levels, and antiandrogen treatment abolishes hypertension, indicating an important role for testosterone. We hypothesized that androgens may play a pivotal role in the enhanced responsiveness to Ang II and hypertension. Female offspring of pregnant rats fed 20% protein (control) or 6% protein diet (protein restricted), at 6 mo of age, were studied. Plasma testosterone and mean arterial pressure in protein-restricted offspring were significantly higher compared to controls. Flutamide treatment (10 mg/kg/day subcutaneously for 10 days) reduced mean arterial pressure in protein-restricted offspring but was without significant effect in controls. Vascular Agtr1/Agtr2 ratio was significantly higher in protein-restricted offspring, an effect that was reversed by flutamide. Flutamide treatment did not have any effect on Agtr1/Agtr2 ratio in controls. Enhanced contractile response to angiotensin II in mesenteric arteries was observed in protein-restricted offspring compared with control. Flutamide treatment reversed the enhanced contractile response to angiotensin II in protein-restricted offspring without significant effect in controls. Vascular reactivity to phenylephrine was similar between the control and protein-restricted offspring with and without flutamide treatment, suggesting that enhanced contractile response and flutamide's reversal effect is specific to angiotensin II. These results suggest that prenatally protein-restricted rats exhibit an enhanced responsiveness to angiotensin II that is testosterone-dependent.

Perinatal protein malnutrition affects mitochondrial function in adult and results in a resistance to high fat diet-induced obesity.

Epidemiological findings indicate that transient environmental influences during perinatal life, especially nutrition, may have deleterious heritable health effects lasting for the entire life. Indeed, the fetal organism develops specific adaptations that permanently change its physiology/metabolism and that persist even in the absence of the stimulus that initiated them. This process is termed "nutritional programming". We previously demonstrated that mothers fed a Low-Protein-Diet (LPD) during gestation and lactation give birth to F1-LPD animals presenting metabolic consequences that are different from those observed when the nutritional stress is applied during gestation only. Compared to control mice, adult F1-LPD animals have a lower body weight and exhibit a higher food intake suggesting that maternal protein under-nutrition during gestation and lactation affects the energy metabolism of F1-LPD offspring. In this study, we investigated the origin of this apparent energy wasting process in F1-LPD and demonstrated that minimal energy expenditure is increased, due to both an increased mitochondrial function in skeletal muscle and an increased mitochondrial density in White Adipose Tissue. Importantly, F1-LPD mice are protected against high-fat-diet-induced obesity. Clearly, different paradigms of exposure to malnutrition may be associated with differences in energy expenditure, food intake, weight and different susceptibilities to various symptoms associated with metabolic syndrome. Taken together these results demonstrate that intra-uterine environment is a major contributor to the future of individuals and disturbance at a critical period of development may compromise their health. Consequently, understanding the molecular mechanisms may give access to useful knowledge regarding the onset of metabolic diseases.