The effect of adrenal denervation on the metabolic effects of hyperammonemia in sheep

The metabolic effect of intravenous infusion of ammonium chloride (60 mumol/(kg body weight.min] was compared in five sheep before and after adrenal denervation. Adrenal denervation completely abolished the hyperglycemic effect of ammonium chloride, diminished the rise of pyruvate and lactate concentration, and failed to influence the lipolytic effect of NH4Cl. It is suggested that the metabolic effects of ammonia are in a different degree related to the action of ammonia on the central nervous system and (i) the hyperammonemic effect of ammonia completely depends on the neurogenic increase of adrenal medullary hormones; (ii) the rise of blood lactate and pyruvate level observed during hyperammonemia is only partially mediated by adrenaline; and (iii) the lipolytic effect of ammonia ion does not depend on the nerve-controlled secretion of adrenal medullary hormones.     

Endocrine regulation of female contact sex pheromone production in the German cockroach, Blattella germanica

ABSTRACT The amount of the major component of the cuticular sex pheromone, 3, 11-dimethyl-2-nonacosanone, on individual female German cockroaches, Blattella germanica (L.), as a function of age was determined by gas-liquid-chromatographic analysis. Accumulation of phermone increased with age in both virgin and mated females. During the first gono-trophic cycle, the pheromone accumulated most rapidly when oocyte growth rates were maximal (days 5–10), and least rapidly while the female carried an ootheca (days 11–32). Pheromone accumulation was similar in virgin and mated females when the same physiological stages (determined by oocyte maturation) were considered. Inhibition of Juvenile Hormone release, through allatectomy, chemicals (precocene or fluoromevalonate), or through mechanical egg case implants, suppressed or delayed pheromone production and oocyte growth. The Juvenile Hormone analogue ZR512 induced allatectomized or head-ligated females and females with chemically or mechanically inhibited corpora allata to produce pheromone and enlarge their basal oocytes. Finally, ZR512 applied to intact females stimulated pheromone production in a dose-dependent manner.     

Endocrine control of nutrition in cyclostomes and fish

• 1.1. The relationship between nutritional patterns and physiological levels of endogenous hormones, in some species of cytosomes and fish, is studied.
• 2.2. Most of the observations are related to species showing a marked life cycle, including natural fasting periods and migrations.
• 3.3. Insulin seems to play a major role in regulating the nutritional metabolism, which appears to be largely dependent on gluconeogenesis and on amino acids supply.

     

Comparison of metabolic effect of ammonia and adrenaline infusions in sheep.

Intravenous infusions of ammonium chloride (62.3 mumol.kg-1.min-1) for 30 min caused a significant increase in blood glucose, lactate, pyruvate and free fatty acid (FFA) levels. A similar effect was also observed during infusion of adrenaline. Propanolol--a beta-receptor blocking agent--completely prevented the rise of blood pyruvate and lactate after adrenaline when 8.3 microgram.kg-1.min-1 of propranolol were infused, but not after NH4Cl administration. Lipolytic actions of adrenaline were completely prevented but that of NH4Cl was only significantly diminished by blockade of beta-receptors with propranolol. It was concluded that the influence of ammonium ions on blood lactate and pyruvate and FFA was not entirely mediated by adrenaline.     

Mechanisms involved in the control of pheromone production in female moths: recent developments

Species‐specific pheromone blends of nocturnal female moths, derived from fatty acid precursors, are produced and released for mate‐finding, and are initiated by the circadian, trophic hormone, Pheromone Biosynthesis Activating Neuropeptide (PBAN). PBAN, produced in the sub‐oesophageal ganglion, is a 33 amino acid neuropeptide with a minimum active core in its FXPRLamide C‐terminal. PBAN acts directly on pheromone gland cells of mature females by binding to a specific G‐protein‐coupled membrane receptor (GPCR), and thereby initiating a signal transduction cascade involving calcium and cAMP. This discussion will review recent developments concerning the identification of the PBAN GPCR, its regulation by juvenile hormone (JH), and its mode of action at the level of the pheromone biosynthetic pathway. The discussion will also include recent developments concerning events occurring as a result of the transfer of pheromonostatic compounds of male origin after mating.     

The effect of nutrition and metabolic status on the development of follicles,oocytes and embryos in ruminants

The impact of nutrition and energy reserves on the fertility of ruminants has been extensively described. However, the metabolic factors and the molecular mechanisms involved in the interactions between nutrition and ovarian function are still poorly understood. These factors could be hormonal (either reproductive and/or metabolic) and/or dietary and metabolic (glucose, amino acids and fatty acids). In this review, we briefly summarize the impact of those nutrients (fatty acids, glucose and amino acids) and metabolic hormones (insulin/IGF-I, growth hormone, T3/4, ghrelin, apelin and the adipokines (leptin, adiponectin and resistin)) implicated in the development of ovarian follicles, oocytes and embryos in ruminants. We then discuss the current hypotheses on the mechanisms of action of these factors on ovarian function. We particularly describe the role of some energy sensors including adenosine monophosphate-activated kinase and peroxisome proliferator-activated receptors in the ovarian cells.     

Endocrine factors in the neonatal adaptation

In this review an attempt has been made to summarize our current knowledge on the involvement of various endocrine systems in the adaptation of the neonate to extrauterine life. Clinical and experimental evidence has been provided to indicate the role of catecholamines, glucocorticoids, prostaglandins, vasopressin, endorphins and the renin-angiotensin-aldosterone system in the cardiovascular and respiratory adaptation. Furthermore, the contribution of prolactin, vasopressin and the renin-angiotensin system to the redistribution of the body fluid compartments after birth and to the regulation of neonatal salt and water metabolism has been demonstrated. It has been concluded that the endocrine reactions induced by birth process and perinatal pathological events are important regulators of successful transition.     

Presence of osteoinductive factors in bovine colostrum

New approaches in the treatment of skeletal defects may benefit from the use of soluble biological factors. We previously standardized a derivative of bovine colostrum (SBCD), deprived of casein and fat and rich in cytokines. In the present study, we tested its possible use as an adjuvant in bone healing. SBCD contained factors involved in stromal cell stimulation and differentiation and induced cytokine production from stimulated mesenchymal stem cells (MSCs). In vitro, SBCD promoted proliferation, migration and, in association with osteogenic factors, osteogenic differentiation of osteoblastic and MSCs. In in vivo experiments of subcutaneous Matrigel injection in mice, SBCD plus hydroxyapatite, but not hydroxyapatite nor SBCD alone, induced recruitment of macrophages and stromal cells. After 60?days, plugs containing SBCD and hydroxyapatite were densely calcified and diffusely positive for osteocalcin, supporting the occurrence of an early osteogenic process. These results indicate that SBCD is a rich source of factors with osteoinductive properties.     

Effects of maternal parity and late gestational nutrition on mRNA abundance for growth factors in the liver of postnatal sheep

The liver is a major metabolic and endocrine organ in growing neonates, but the extent to which its hormone receptor (R) sensitivity is potentially determined by maternal parity and the mother's nutritional environment is unknown. This was therefore investigated by sampling livers from postnatal sheep born to nulliparous or multiparous mothers. Offspring were sampled 1 or 30 days after birth from mothers consuming either 100 or 50% [i.e., nutrient-restricted (NR) group] of total metabolizable energy requirements from 110 days gestation to term ( approximately 147 days). Regardless of maternal diet, offspring of nulliparous mothers were lighter at birth and had smaller livers. By 1 mo of age, they exhibited catch-up growth, an adaptation not seen when mothers were NR, but they retained their lighter livers. At both sampling ages, livers from offspring born to nulliparous mothers exhibited increased mRNA abundance for growth hormone (GH) receptor, IGF-IR, plus hepatocyte growth factor (HGF); and at day 1 only IGF-I, but not IGF-IIR mRNA was decreased. In addition, mRNA for IGF-II, the HGFR, c-Met, and Bax were persistently reduced in these offspring. Effects of parity were largely unaffected by maternal nutrient restriction. Maternal parity therefore has a substantial effect on liver size during postnatal development and its receptor population that is not dependent on maternal diet. First-born offspring appear to exhibit a resetting of the endocrine control of hepatic growth within the HGF and GH-IGF axis, which could have later consequences after their growth has caught up.     

营养因子对干酪乳杆菌LC2W胞外多糖合成的影响

针对影响干酪乳杆菌LC2W产胞外多糖的主要营养因子:葡萄糖、酪蛋白胨和酵母提取物进行了单因素及正交试验,确定了合成胞外多糖的最适组成为葡萄糖60 g/L,酪蛋白胨16 g/L ,酵母提取物10 g/L,其中酪蛋白胨影响差异极显著.验证试验表明,以优化后的培养基进行发酵试验,37 ℃培养24 h,所得胞外多糖量为120.37 mg/L,较原来提高67.97 %.     

Neonatal piglet survival: impact of sow nutrition around parturition on fetal glycogen deposition and production and composition of colostrum and transient milk

Piglet survival is a major problem, especially during the first 3 days after birth. Piglets are born deficient of energy, but at the same time they have a very high energy requirement because of high physical activity, high need for thermoregulation (because of their lean body with low insulation) and high heat production in muscle tissues. To be able to survive, newborn piglets may rely upon three different sources of energy, namely, glycogen, colostrum and transient milk, which orchestrate to cover their energy requirements. Piglets are born with limited amounts of energy in glycogen depots in the liver and muscle tissues and these depots are sufficient for normal activity for ∼16 h. Intake and oxidation of fat and lactose from colostrum must supply sufficient amount of energy to cover at least another 18 h until transient milk becomes available in the sow udder ∼34 h after the first piglet is born. Selection for large litters during the last two decades has challenged piglets even further during the critical neonatal phase because the selection programs indirectly decreased birth weight of piglets and because increased litter size has increased the competition between littermates. Different attempts have been made to increase the short-term survival of piglets, that is, survival until day 3 of lactation, by focusing on improving transfer of vital maternal energy to the offspring, either in utero or via mammary secretions. Thus, the present review addresses how sow nutrition in late gestation may favor survival of newborn piglets by increasing glycogen depots, improving colostrum yield or colostrum composition, or by increasing production of transient milk.     

Local production of IgG4 in human colostrum

Total IgG4 levels were determined in 27 colostrum and 27 plasma paired samples by using RIA techniques, and total IgG was determined on the same pairs by using radial immunodiffusion. In colostrum, the mean IgG4 level was 4.6 micrograms/ml (0.6 to 19.0), and in the plasma the mean IgG4 level was 170.5 micrograms/ml (30 to 920). IgG averaged 42.3 micrograms/ml (12 to 240) in colostrum and 7980.9 micrograms/ml (3250 to 16,000) in plasma. Of colostral IgG, 15.3% was IgG4, whereas only 3.5% of plasma IgG was IgG4. Specific IgG4 antibodies to beta-lactoglobulin, bovine serum albumin, bermuda grass, and alpha-gliadin were also assayed. In six patients, strong evidence was found for local mammary production of IgG4-specific antibodies.     

Improvement of bacterial cellulose production by manipulating the metabolic pathways in which ethanol and sodium citrate involved

Nowadays, bacterial cellulose has played more and more important role as new biological material for food industry and medical and industrial products based on its unique properties. However, it is still a difficult task to improve the production of bacterial cellulose, especially a large number of byproducts are produced in the metabolic biosynthesis processes. To improve bacterial cellulose production, ethanol and sodium citrate are added into the medium during the fermentation, and the activities of key enzymes and concentration of extracellular metabolites are measured to assess the changes of the metabolic flux of the hexose monophosphate pathway (HMP), the Embden–Meyerhof–Parnas pathway (EMP), and the tricarboxylic acid cycle (TCA). Our results indicate that ethanol functions as energy source for ATP generation at the early stage of the fermentation in the HMP pathway and the supplementation of ethanol significantly reduces glycerol generation (a major byproduct). While in the EMP pathway, sodium citrate plays a key role, and its supplementation results in the byproducts (mainly acetic acid and pyruvic acid) entering the gluconeogenesis pathway for cellulose synthesis. Furthermore, by adding ethanol and sodium citrate, the main byproduct citric acid in the TCA cycle is also reduced significantly. It is concluded that bacterial cellulose production can be improved by increasing energy metabolism and reducing the formation of metabolic byproducts through the metabolic regulations of the bypasses.     

Endocrine and metabolic regulation of renal drug transporters

Renal xenobiotic transporters are important determinants of urinary secretion and reabsorption of chemicals. In addition to glomerular filtration, these processes are key to the overall renal clearance of a diverse array of drugs and toxins. Alterations in kidney transporter levels and function can influence the efficacy and toxicity of chemicals. Studies in experimental animals have revealed distinct patterns of renal transporter expression in response to sex hormones, pregnancy, and growth hormone. Likewise, a number of disease states including diabetes, obesity, and cholestasis alter the expression of kidney transporters. The goal of this review is to provide an overview of the major xenobiotic transporters expressed in the kidneys and an understanding of metabolic conditions and hormonal factors that regulate their expression and function. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:407–421, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21435