The effect of orthopaedic surgeons' and interventional radiologists' availability on the priority treatment sequence for hemodynamically unstable pelvic fractures: a survey of US Level I trauma centers.

BACKGROUND: Most guidelines recommend both pelvic packing (PP) and angioembolization for hemodynamically unstable pelvic fractures, however their sequence varies. Some argue to use PP first because orthopaedic surgeons are more available than interventional radiologists; however, there is no data confirming this. METHODS: This cross-sectional survey of 158 trauma medical directors at US Level I trauma centers collected the availability of orthopaedic surgeons and interventional radiologists, the number of orthopaedic trauma surgeons trained to manage pelvic fractures, and priority treatment sequence for hemodynamically unstable pelvic fractures. The study objective was to compare the availability of orthopaedic surgeons to interventional radiologists and describe how the availability of orthopaedic surgeons and interventional radiologists affects the treatment sequence for hemodynamically unstable pelvic fractures. Fisher's exact, chi-squared, and Kruskal-Wallis tests were used, alpha = 0.05. RESULTS: The response rate was 25% (40/158). Orthopaedic surgeons (86%) were on-site more often than interventional radiologists (54%), p = 0.003. Orthopaedic surgeons were faster to arrive 39% of the time, and interventional radiologists were faster to arrive 6% of the time. There was a higher proportion of participants who prioritized PP before angioembolization at centers with above the average number (> 3) of orthopaedic trauma surgeons trained to manage pelvic fractures, as among centers with equal to or below average, p = 0.02. Arrival times for orthopaedic surgeons did not significantly predict prioritization of angioembolization or PP. CONCLUSIONS: Our results provide evidence that orthopaedic surgeons typically are more available than interventional radiologists but contrary to anecdotal evidence most participants used angioembolization first. Familiarity with the availability of orthopaedic surgeons and interventional radiologists may contribute to individual trauma center's treatment sequence.

Antenatal antipsychotic exposure induces multigenerational and gender-specific programming of adiposity and glucose tolerance in adult mouse offspring.

Second-generation antipsychotics (SGAs) are well known for their metabolic side effects in humans, including obesity and diabetes. These compounds are maintained during pregnancy to prevent the relapse of psychoses, but they readily diffuse across the placenta to the fetus, as documented with the widely-prescribed drug olanzapine (OLZ). However, observational studies have provided conflicting results on the potential impact of SGAs on fetal growth and body weight, and their effects on metabolic regulation in the offspring. For this reason, our study has tested whether antenatal exposure of CD1 mice to OLZ influenced metabolic outcomes in the offspring of the first (F1) and second (F2) generations. In F1 mice, OLZ antenatal treatment caused a decrease in neonatal body weight in both genders, an effect that persisted throughout life only in male animals. Interestingly, F1 female mice also displayed altered glucose homoeostasis. F2 mice, generated by mating normal males with F1 female mice exposed to OLZ during antenatal life, exhibited higher neonatal body weights which persisted only in F2 female animals. This was associated with expansion of fat mass and a concordant pattern of adipose tissue gene expression. Moreover, male and female F2 mice were glucose-intolerant. Thus, our study has demonstrated that antenatal OLZ exposure induces multigenerational and gender-specific programming of glucose tolerance in the offspring mice as adults, and points to the need for careful monitoring of children exposed to SGAs during pregnancy.

Oxidative and energetic stresses mediate beta-cell dysfunction induced by PGC-1α.

AIM: Alteration of functional beta-cell mass in adults can be programmed by adverse events during fetal life. Previously, it was demonstrated that high glucocorticoid (GC) levels during fetal life participate in this programming by inhibition of beta-cell development. More specifically, GC levels stimulate expression of peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α), a transcriptional co-regulator of the GC receptor (GR), which per se impairs beta-cell mass and function when overexpressed. As PGC-1α is also a potent inducer of mitochondrial biogenesis, our study aimed to determine how PGC-1α modifies mitochondrial function in beta cells and how it might regulate insulin secretion. METHODS: Beta-cell function was studied in mice overexpressing PGC-1α specifically in beta cells and in MIN6 cells overexpressing PGC-1α in vitro. RESULTS: PGC-1α overexpression in beta cells in vivo leads to a reduced beta-cell mass early in fetal life, whereas PGC-1α overexpression in vitro stimulates mitochondrial biogenesis and respiratory activity without improving ATP production, while increasing oxidative stress and impairing insulin secretion in response to glucose. While oxidative stress with PGC-1α overexpression in beta cells activates AMPK, it has also been revealed that blocking such oxidative stress or AMPK activation restores insulin secretion. CONCLUSION: PGC-1α induces oxidative stress, which disrupts insulin secretion by AMPK activation. Thus, control of oxidative or energetic stress in beta cells may help to restore insulin secretion.

[Hyperammonemic encephalopathy as the presenting feature of a relapsing multiple myeloma]. / Encéphalopathie hyperammoniémique révélant une récidive de myélome.

INTRODUCTION: Hyperammonemia attributed to multiple myeloma has been rarely reported. CASE REPORT: We report a 63-year-old man who was admitted to an intensive care unit for confusion and altered mental status progressing to coma that was related to a relapsing multiple myeloma. Chemotherapy allowed the reduction of serum ammonia and the return to a normal state of consciousness. CONCLUSION: Hyperammonemic encephalopathy is a rare complication of multiple myeloma and is associated with high in-patient mortality. To our knowledge, this is the first case of hyperammonemic encephalopathy due to a relapsing myeloma diagnosed and treated in intensive care unit.

Metabolic roles of PGC-1α and its implications for type 2 diabetes.

PGC-1α is a transcriptional coactivator expressed in brown adipose tissue, liver, pancreas, kidney, skeletal and cardiac muscles, and the brain. This review presents data illustrating how PGC-1α regulates metabolic adaptations and participates in the aetiology of type 2 diabetes (T2D). Studies in mice have shown that increased PGC-1α expression may be beneficial or deleterious, depending on the tissue: in adipose tissue, it promotes thermogenesis and thus protects against energy overload, such as seen in diabetes and obesity; in muscle, PGC-1α induces a change of phenotype towards oxidative metabolism. In contrast, its role is clearly deleterious in the liver and pancreas, where it induces hepatic glucose production and inhibits insulin secretion, changes that promote diabetes. Previous studies by our group have also demonstrated the role of PGC-1α in the fetal origins of T2D. Overexpression of PGC-1α in ß cells during fetal life in mice is sufficient to induce ß-cell dysfunction in adults, leading to glucose intolerance. PGC-1α also is associated with glucocorticoid receptors in repressing expression of Pdx1, a key ß-cell transcription factor. In conclusion, PGC-1α participates in the onset of diabetes through regulation of major metabolic tissues. Yet, it may not represent a useful target for therapeutic strategies against diabetes as it exerts both beneficial and deleterious actions on glucose homoeostasis, and because PGC-1α modulation is involved in neurodegenerative diseases. However, its role in cellular adaptation shows that greater comprehension of PGC-1α actions is needed.

Incretin-based therapy and pancreatic beta cells.

Type 2 diabetes (T2D) is a complex, progressive disease with life-threatening complications and one of the most serious public-health problems worldwide. The two main mechanisms of T2D pathogenesis are pancreatic beta cell dysfunction and insulin resistance. It is now recognized that pancreatic beta cell dysfunction is a necessary factor for T2D development. Traditional therapies for controlling blood glucose are suboptimal as they fail to meet target goals for many patients. Glucagon-like peptide-1 receptor agonists (GLP1RA) and dipeptidyl peptidase-4 inhibitors (DPP4I) are an attractive class of therapy because they reduce blood glucose by targeting the incretin hormone system and, in particular, have the potential to positively affect pancreatic beta cell biology. This review outlines our current understanding of pancreatic beta cell incretin system dysfunction in T2D and summarizes recent evidence of the effect of incretin-based therapies on beta cell function and mass. Incretin-based therapies have shown strong evidence for beneficial effects on beta cell function and mass in animal studies. In humans, incretin-based therapies are effective glucose-lowering agents, but further study is still required to evaluate their long-term effects on beta cell function and safety as well as beta cell mass expansion.

Comparative minimum inhibitory and mutant prevention drug concentrations of enrofloxacin, ceftiofur, florfenicol, tilmicosin and tulathromycin against bovine clinical isolates of Mannheimia haemolytica.

Mannheimia haemolytica is the most prevalent cause of bovine respiratory disease (BRD) and this disease accounts for 75% of morbidity, 50-70% of feedlot deaths and is estimated to cost up to $1 billion dollars annually in the USA. Antimicrobial therapy is essential for reducing morbidity, mortality and impacting on the financial burden of this disease. Due to the concern of increasing antimicrobial resistance, investigation of antibacterial agents for their potential for selecting for resistance is of paramount importance. A novel in vitro measurement called the mutant prevention concentration (MPC) defines the antimicrobial drug concentration necessary to block the growth of the least susceptible cells present in high density (≥10(7) colony forming units/ml) bacterial populations such as those seen in acute infection. We compared the minimum inhibitory concentration (MIC) and MPC values for 5 antimicrobial agents (ceftiofur, enrofloxacin, florfenicol, tilmicosin, tulathromycin) against 285 M. haemolytica clinical isolates. The MIC(90)/MPC(90) values for each agent respectively were as follows: 0.016/2, 0.125/1, 2/≥16, 8/≥32, 2/8. Dosing to achieve MPC concentrations (where possible) may serve to reduce the selection of bacterial subpopulations with reduced antimicrobial susceptibility. The rank order of potency based on MIC(90) values was ceftiofur > enrofloxacin > florfenicol = tulathromycin > tilmicosin. The rank order of potency based on MPC(90) values was enrofloxacin > ceftiofur > tulathromycin > florfenicol ≥ tilmicosin.

In vitro killing of Escherichia coli, Staphylococcus pseudintermedius and Pseudomonas aeruginosa by enrofloxacin in combination with its active metabolite ciprofloxacin using clinically relevant drug concentrations in the dog and cat.

Enrofloxacin is a fluoroquinolone antibacterial agent used to treat infections in companion animals. Enrofloxacin's antimicrobial spectrum includes Gram positive and Gram-negative bacteria and demonstrates concentration-dependent bacteriocidal activity. In dogs and cats, enrofloxacin is partially metabolized to ciprofloxacin and both active agents circulate simultaneously in treated animals at ratios of approximately 60-70% enrofloxacin to 30-40% ciprofloxacin. We were interested in determining the killing of companion animal isolates of Escherichia coli, Staphylococcus pseudintermedius and Pseudomonas aeruginosa by enrofloxacin and ciprofloxacin combined using clinically relevant drug concentrations and ratios. For E. coli isolates exposed to 2.1 and 4.1µg/ml of enrofloxacin/ciprofloxacin at 50:50, 60:40 and 70:30 ratios, a 1.7-2.5log(10) reduction (94-99% kill) was seen following 20min of drug exposure; 0.89-1.7log(10) (92-99% kill) of S. pseudintermedius following 180min of drug exposure; 0.85-3.4log(10) (98-99% kill) of P. aeruginosa following 15min of drug exposure. Killing of S. pseudintermedius was enhanced in the presence of enrofloxacin whereas killing of P. aeruginosa was enhanced in the presence of ciprofloxacin. Antagonism was not seen when enrofloxacin and ciprofloxacin were used in kill assays. The unique feature of partial metabolism of enrofloxacin to ciprofloxacin expands the spectrum of enhanced killing of common companion animal pathogens.

Exposure in utero to maternal diabetes leads to glucose intolerance and high blood pressure with no major effects on lipid metabolism.

AIM: Recent evidence shows that adult metabolic disease may originate from an adverse fetal environment that can alter organ development and function in postnatal life. This study aimed to analyze the effect of exposure in utero to maternal diabetes on the development of the metabolic syndrome in the offspring. METHODS: Pregnant rats were made diabetic (blood glucose was 20mM) with a single streptozotocin injection on day 0 of gestation. Offspring from diabetic mothers (DMO) and control mothers (CMO) were followed from birth to 12 months of age. In these animals, metabolic parameters, such as glucose tolerance, insulin sensitivity and plasma lipid levels, as well as pancreatic insulin and morphology were studied. RESULTS: Compared with controls, DMO offspring had normal birth weights, but impaired postnatal growth that persisted throughout life. Metabolic tests revealed that DMO offspring also showed impaired glucose tolerance at six months associated with decreased insulin sensitivity and low insulin secretion. In older animals (12 months old), this phenotype persisted, but to a lesser extent. The DMO offspring also presented with high blood pressure and decreased levels of fasting plasma triglycerides, but normal plasma NEFA, and HDL and total cholesterol. CONCLUSION: Altogether, these results show that our model of exposure in utero to maternal diabetes led to normal birth weights, and induced transient glucose intolerance and increased blood pressure with no major effects on lipid metabolism. It also suggests that a hyperglycaemic fetal environment may be able to 'programme' hypertension and glucose intolerance, but not alter lipid metabolism.

Genetic evidence of the programming of beta cell mass and function by glucocorticoids in mice.

AIMS/HYPOTHESIS: Prenatal exposure to excess glucocorticoids associates with low birthweight in rodents, primates and humans and its involvement in programming glucose homeostasis is suspected. Our aim was to further dissect the role of glucocorticoids on beta cell development and function in mice. METHODS: Using the model of maternal general food restriction during the last week of pregnancy, we thoroughly studied in the CD1 mouse-mothers and fetal and adult offspring--the pancreatic, metabolic and molecular consequences of maternal undernutrition associated with excess glucocorticoids. The specific involvement of the glucocorticoid receptor (GR) was studied in mutant fetuses lacking GR in pancreatic precursors or mature beta cells. RESULTS: Maternal general food restriction in the mouse is associated with decreased maternal glucose and increased corticosterone levels. Fetuses from underfed dams had increased corticosterone levels, decreased pancreatic endocrine gene expression but increased exocrine gene expression and a lower beta cell mass. The offspring of these dams had a low birthweight, permanent postnatal growth retardation and, as adults, impaired glucose tolerance, decreased beta cell mass (-50%) and massively reduced islet expression (-80%) of most of the genes involved in beta cell function (e.g. Pdx1, Sur1 [also known as Abcc8], insulin). Moreover, using mutant fetuses lacking GR in pancreatic precursors or beta cells we show that the deleterious effect of undernutrition on fetal beta cell development requires the presence of the GR in pancreatic precursor cells. CONCLUSIONS/INTERPRETATION: These results demonstrate the crucial role of excess fetal glucocorticoids and the importance of GR signalling in progenitor cells to programme beta cell mass and dysfunction.

Different mechanisms operating during different critical time-windows reduce rat fetal beta cell mass due to a maternal low-protein or low-energy diet.

AIMS/HYPOTHESIS: Adverse events during intra-uterine life may programme organ growth and favour disease later in life. In animals, protein or energy restriction during gestation alters the development of the endocrine pancreas, even though the duration of malnutrition is different. Here, we evaluate the specific effects of both diets during different periods of gestation and the mechanisms underlying the decreased beta cell mass. METHODS: Pregnant Wistar rats were fed either a low-protein or a low-energy diet during the last week of gestation or throughout gestation. Fetuses and their pancreases were analysed at days 15 and 21 of gestation. RESULTS: The low-energy diet reduced the beta cell mass from 21-day-old fetuses by 33 or 56% when administered during the last week or throughout gestation, respectively. Fetal corticosterone levels were increased. At 15 days of fetal age, the number of cells producing neurogenin 3 (NEUROG3) or pancreatic and duodenal homeobox gene 1 (PDX-1) was reduced. Neither islet vascularisation nor beta cell proliferation was affected. The low-protein diet, in contrast, was more efficient in decreasing the fetal beta cell mass when given during the last week of gestation (-53%) rather than throughout gestation (-33%). Beta cell proliferation was decreased by 50% by the low-protein diet, independently of its duration, and islet vascularisation was reduced. This diet did not affect NEUROG3- or PDX-1-positive cell numbers. CONCLUSION/INTERPRETATION: Although both diets reduced the fetal beta cell mass, the cellular mechanisms and the sensitivity windows were different. Early alteration of neogenesis due to elevated corticosterone levels is likely to be responsible for the decreased beta cell mass in low-energy fetuses, whereas impaired beta cell proliferation and islet vascularisation at later stages are implicated in low-protein fetuses.

Glucocorticoid signalling affects pancreatic development through both direct and indirect effects.

AIMS/HYPOTHESIS: Beta cell development is sensitive to glucocorticoid levels. Although direct effects of glucocorticoids on pancreatic precursors have been shown to control beta cell mass expansion, indirect effects of these hormones on pancreatic development remain unexplored. This issue was addressed in mice lacking the glucocorticoid receptor (GR) in the whole organism. MATERIALS AND METHODS: The pancreatic phenotype of GR(null/null) mice was studied at fetal ages (embryonic day [E]) E15.5 and E18 by immunohistochemistry and beta cell fraction measurements. To distinguish between direct and indirect effects, mutant E15.5 fetal pancreata were grafted under the kidney capsule of immunodeficient mice and analysed after 1 week. RESULTS: E18 GR(null/null) fetuses had smaller digestive tracts and tiny pancreata. Massive pancreatic disorganisation and apoptosis were observed despite the presence of all cell types. E15.5 GR(null/null) mutants were indistinguishable from wild-type regarding pancreatic size, tissue structure and organisation, beta cell fraction and production of exocrine transcription factor Ptf1a, neurogenin 3 and Pdx-1. Grafting E15.5 GR(null/null) pancreata into a GR-expressing environment rescued the increased apoptosis and mature islets were observed, suggesting that GR(null/null) pancreatic cell death can be attributed to indirect effects of glucocorticoids on this tissue. Heterozygous GR(+/null) mutants with reduced GR numbers showed no apoptosis but increased beta cell fraction at E18 and the adult age, strengthening the importance of an accurate GR dosage on beta cell mass expansion. CONCLUSIONS/INTERPRETATION: Our results provide evidence for GR involvement in pancreatic tissue organisation and survival through indirect effects. GR does not appear necessary for early phases, but its accurate dosage is critical to modulate beta cell mass expansion at later fetal stages, presumably through direct effects.

Nutrition, glucocorticoids and pancreas development.

Low birth weight is strongly predictive of hypertension, cardiovascular diseases, obesity, insulin resistance and diabetes. The mechanisms by which fetal undernutrition and, hence, low birth weight increase the risk of developing these diseases are unclear. To investigate the hypothesis of a primary defect in beta-cell development, we designed a rat model of undernutrition, involving an overall reduction in maternal food intake. In this model, fetuses with intrauterine growth retardation have a decreased beta-cell mass, which persists into adulthood and ultimately causes glucose intolerance, thereby mimicking features of the metabolic syndrome. Maternal undernutrition causes elevations in glucocorticoid concentrations, which, in turn, cause a reduction in beta-cell mass in the fetus. Our data also suggest a key role of glucocorticoids when nutrient supply is normal. By combining in-vitro studies with in-vivo investigations in mice lacking the glucocorticoid receptor in the whole organism or in specific pancreatic cell populations, we have shown that the glucocorticoid receptor is critical for ensuring pancreatic architecture and survival, as well as for beta-cell mass expansion during a critical developmental window. Glucocorticoids act on precursor cells before the onset of hormone gene expression and are likely to programme beta-cell differentiation by modifying the balance of specific transcription factors, mostly Pdx-1. Glucocorticoids should therefore be considered as important hormones in pancreatic development, in situations of both normal nutrition and undernutrition. To investigate whether this is also the case in human pancreatic development, we studied the expression of the glucocorticoid receptor and that of the transcription factor Pdx-1 on pancreatic specimens from very early to late stages of development of the human embryo. In terms of beta-cell ontogeny, expression of the glucocorticoid receptor in the pancreas coincides with that of the transcription factor Pdx-1 in beta cells. These results are consistent with a possible role for glucocorticoids during human pancreatic development.

Perioperative factors and outcome associated with massive blood loss during major liver resections.

BACKGROUND: Mortality and morbidity rates from major liver resections have decreased sharply over the past 25 years. This improvement is due to a better understanding of liver anatomy and the introduction of new operative techniques, but also to improved anesthetic perioperative support. Certain cases are still associated with voluminous blood loss. These patients may be at higher risk for postoperative problems and increased length of stay (LOS) in hospital. METHODS: We have retrospectively reviewed 115 patients undergoing major hepatic resections (three or more anatomic segments) with respect to operative blood loss (EBL). Those with an EBL >or=5000 ml (group 1; n = 39) were compared to those with an EBL or=70 years), tumor size, mortality, morbidity, and hospital LOS were examined. Operative reports were examined for any explanation for excessive blood loss. Anesthetic support often entailed the use of a rapid infusion system. RESULTS: The EBL was 7692+/-3848 ml for group 1 and 1359+/-514 ml for group 2. Primary liver tumors were resected in 20 patients in group 1 and in 18 patients in group 2. The remaining resections were for metastatic tumors, primarily colorectal in origin. In group 1, 13/39 patients had a left hepatectomy compared to 10/42 patients in group 2 (p=0.34). The overall mortality was 5/1 15. Four deaths occurred in group 1 and one in group 2 (p=0.16). Two deaths in group 1 were intra-operative (hemorrhage, air embolism). There was no difference in the number of patients with complications, 12/ 39 in group 1 and 8/42 in group 2 (p=0.22). Two patients in group 1 required re-operation for bleeding; there were none in group 2. Largest tumor size did not differ between the two groups (p=0.08), nor did the proportion of patients aged 70 years or older (p=0.06). There was no difference in hospital LOS (10.54+/-6.1 vs 8.90+/-4.7 days, p=0.2l). Review of operative notes in group 1 indicated no unusual problems in 13/39, large tumors or proximity to the inferior vena cava in 10/39, and bleeding from the middle hepatic vein in 7/39. Three patients in group 1 required total vascular exclusion for tumor removal; there were none in group 2. DISCUSSION: Massive EBL during major liver resection seems to be provoked by tumors near the inferior vena cava or major hepatic veins, or injury to the middle hepatic vein during operation, and not by patient age, tumor size alone, or type of hepatectomy. However, by avoiding prolonged hypotension and hypothermia with the use of rapid infusion devices, the perioperative course of these patients does not differ from those with much less EBL.

Decreased beta-cell proliferation impairs the adaptation to pregnancy in rats malnourished during perinatal life.

We investigated the cellular mechanisms responsible for the inability of 8-month-old previously malnourished (PM) females to adapt their beta-cell mass during pregnancy. The evolution during pregnancy of beta-cell fraction, size and proliferation was studied. At day 21 of pregnancy beta-cell fraction increased less in PM than in control females, compared with their non-pregnant values. A slight beta-cell hypertrophy was observed during pregnancy in both groups. In control females, beta-cell 5-bromo-2'-deoxyuridine (BrdU) labelling index (LI) increased from 0.07+/-0.04% before pregnancy to 1.13+/-0.20% at day 12 and decreased thereafter to reach again basal levels at day 21. In PM females, beta-cell proliferation rate was decreased at day 12 (0.74+/-0.15%, P<0.05) but similar to controls at all other stages studied. Separate analysis of the head and tail parts of the pancreas in control animals revealed that the beta-cell fraction during pregnancy increased more in the head than in the tail; similarly, BrdU LI increased 20-fold in the head and 10-fold in the tail, compared with non-pregnant values. In PM females, no adaptation of beta-cell fraction could be observed in the head, where BrdU LI was decreased by half at day 12 of pregnancy. In PM females the lactogenic activity was twice that of controls at day 12 whereas all beta-cells expressed the prolactin receptor. In conclusion, perinatal malnutrition impairs subsequent adaptation to pregnancy by decreasing beta-cell proliferation in the head of the pancreas at a critical time during pregnancy.

Maternal undernutrition during late gestation-induced intrauterine growth restriction in the rat is associated with impaired placental GLUT3 expression, but does not correlate with endogenous corticosterone levels.

Fetal intrauterine growth restriction (IUGR) is a frequently occurring and serious complication of pregnancy. Infants exposed to IUGR are at risk for numerous perinatal morbidities, including hypoglycemia in the neonatal period, as well as increased risk of later physical and/or mental impairments, cardiovascular disease and non-insulin-dependent diabetes mellitus. Fetal growth restriction most often results from uteroplacental dysfunction during the later stage of pregnancy. As glucose, which is the most abundant nutrient crossing the placenta, fulfills a large portion of the fetal energy requirements during gestational development, and since impaired placental glucose transport is thought to result in growth restriction, we investigated the effects of maternal 50% food restriction (FR50) during the last week of gestation on rat placental expression of glucose transporters, GLUT1, GLUT3 and GLUT4, and on plasma glucose content in both maternal and fetal compartments. Moreover, as maternal FR50 induces fetal overexposure to glucocorticoids and since these hormones are potent regulators of placental glucose transporter expression, we investigated whether putative alterations in placental GLUT expression correlate with changes in maternal and/or fetal corticosterone levels. At term (day 21 of pregnancy), plasma glucose content was significantly reduced (P<0.05) in mothers subjected to FR50, but was not affected in fetuses. Food restriction reduced maternal body weight (P<0.001) but did not affect placental weight. Plasma corticosterone concentration, at term, was increased (P<0.05) in FR50 mothers. Fetuses from FR50 mothers showed reduced body weight (P<0.001) but higher plasma corticosterone levels (P<0.05). Adrenalectomy (ADX) followed by corticosterone supplementation of the mother prevented the FR50-induced rise in maternal plasma corticosterone at term. Food restriction performed on either sham-ADX or ADX mothers induced a similar reduction in the body weight of the pups at term (P<0.01). Moreover, plasma corticosterone levels were increased in pups from sham-ADX FR50 mothers (P<0.01) and in pups from ADX control mothers (P<0.01). Western blot analysis of placental GLUT proteins showed that maternal FR50 decreased placental GLUT3 protein levels in all experimental groups at term (P<0.05 and P<0.01), but did not affect either GLUT1 or GLUT4 protein levels. Northern blot analysis of placental GLUT expression showed that both GLUT1 and GLUT3 mRNA were not affected by the maternal feeding regimen or surgery. We concluded that prolonged maternal malnutrition during late gestation decreases maternal plasma glucose content and placental GLUT3 glucose transporter expression, but does not obviously affect fetal plasma glucose concentration. Moreover, the present results are not compatible with a role of maternal corticosterone in the development of growth-restricted rat fetuses.

Endocrine pancreas development is altered in foetuses from rats previously showing intra-uterine growth retardation in response to malnutrition.

AIMS/HYPOTHESIS: We have shown that perinatal malnutrition decreases beta-cell mass at birth and impairs the adaptation of the endocrine pancreas to a subsequent pregnancy. The aim of this study is to investigate the impact of this maternal inadaptation on the development of endocrine pancreas in foetuses. METHODS: Female rats malnourished during their perinatal life and showing intra-uterine growth retardation at birth were mated at 8 months of age. The development of the endocrine pancreas was studied at embryonic days 14, 17 and 20 in their foetuses by immunohistochemistry and morphometrical measurements on pancreatic sections. RESULTS: At embryonic day 20, both alpha and beta-cell fractions were decreased in foetuses from IUGR dams. Beta-cell mass was reduced (197 +/- 27 microg, vs 281 +/- 40 microg in control, p < 0.01) and so were insulin content and islet number per cm(2), as in the first generation foetuses. At embryonic day 14, the number of cells expressing only insulin was decreased by half in foetuses from intra-uterine growth retardation dams. At embryonic day 17, 50 % of the homeodomain protein Pdx-1 cell population expressed insulin but all the insulin cells expressed Pdx-1 in both groups; in foetuses from intra-uterine growth retardation dams the number of epithelial cells expressing Pdx-1 was decreased (415 +/- 40 cells/ mm(2) vs 481 +/- 28 cells/mm(2) in control foetuses, p < 0.05) and the mesenchymal fraction in the pancreas was increased by 36 % ( p < 0.05). CONCLUSION/INTERPRETATION: Early malnutrition decreases beta-cell mass in the first generation of offspring and impairs the subsequent beta-cell adaptation to pregnancy. The beta-cell alteration is also present in the next generation and involves a decreased expansion of the epithelial population expressing Pdx-1.

Perinatal malnutrition programs sympathoadrenal and hypothalamic-pituitary-adrenal axis responsiveness to restraint stress in adult male rats.

In humans, an altered control of cortisol secretion was reported in adult men born with a low birth weight making the hypothalamic-pituitary-adrenal (HPA) axis a possible primary target of early life programming. In rats, we have recently shown that maternal food restriction during late pregnancy induces both an intrauterine growth retardation and an overexposure of fetuses to maternal corticosterone, which disturb the development of the HPA axis in offspring. The first aim of this work was to investigate, in adult male rats, whether perinatal malnutrition has long-lasting effects on the HPA axis activity during both basal and stressful conditions. Moreover, as the HPA axis and sympathetic nervous system are both activated by stress, the second aim of this work was to investigate, in these rats, the adrenomedullary catecholaminergic system under basal and stressful conditions. This study was conducted on 4-month-old male rats malnourished during their perinatal life and on age-matched control animals. Under basal conditions, perinatal malnutrition reduced body weight and plasma corticosteroid-binding globulin (CBG) level but increased mineralocorticoid receptor (MR) gene expression in CA1 hippocampal area. After 30 min of restraint, perinatally malnourished (PM) rats showed increased plasma noradrenaline, adrenocorticotropin hormone (ACTH) and corticosterone concentrations similarly as controls, but calculated plasma-free corticosterone concentration was significantly higher and adrenaline level lower than controls. During the phase of recovery, PM rats showed a rapid return of plasma ACTH and corticosterone concentrations to baseline levels in comparison with controls. These data suggest that in PM rats, an elevation of basal concentrations of corticosterone, in face of reduced CBG and probably increased hippocampal MR lead to a much larger impact of corticosterone on target cells that mediate the negative-feedback mechanism on the activities of both the HPA axis and sympathoadrenal one.

Glucocorticoids impair fetal beta-cell development in rats.

In rats, poor fetal growth due to maternal food restriction during pregnancy is associated with decreased beta-cell mass at birth and glucose intolerance in adulthood. Overexposure to glucocorticoids in utero can induce intrauterine growth retardation in humans and animals and subsequent glucose intolerance in rodents. The aims of this study were to investigate whether glucocorticoid overexposure mediates the effect of undernutrition on beta-cell mass and to study their potential role in normally nourished rats. Undernutrition significantly increased maternal and fetal corticosterone levels. Twenty-one-day-old fetuses with undernutrition showed growth retardation and decreased pancreatic insulin content; adrenalectomy and subcutaneous corticosterone implants in their dams prevented the maternal corticosterone increase and restored fetal beta-cell mass. In fetuses with normal nutrition, fetal corticosterone levels were negatively correlated to fetal weight and insulin content; fetal beta-cell mass increased from 355 +/- 48 microg in sham to 516 +/- 160 microg after maternal adrenalectomy; inhibition of steroid production by metyrapone induced a further increase to 757 +/- 125 microg. Our data support the new concept of a negative role of glucocorticoids in fetal beta-cell development.