Growth Hormone Concentrations Research Articles

The clinical complexity of patients with acromegaly

ObjectivesThe main aim of the study was to investigate the factors related to the biopsychosocial complexity in the group of patients with acromegaly with different disease activity. MethodsA cross-sectional observational study was performed. First, a linguistic adaptation of the INTERMED – self-assessment questionnaire (IMSA) and after that the assessment of the biopsychosocial complexity among patients with acromegaly and the factors which relate to the complexity was made. The following tools were used to assess: biopsychosocial complexity: The INTERMED –self-assessment (IMSA); quality of life: The World Health Organization Quality of Life – BREF (WHOQoL) and Acromegaly Quality of Life questionnaire (AcroQol); mental state: The General Health Questionnaire – 28 (GHQ-28). ResultsThe final analysis included 71 patients. According to the principal component analysis the mental state (GHQ-28) and the quality of life (AcroQol) are the most important factors related to the clinical complexity among patients with acromegaly. In the model created by a stepwise regression analysis for the total IMSA score higher growth hormone (GH) concentration, longer illness duration, and better general quality of life were included as the protective factors of the clinical complexity. By contrast, a high score in the severe depression subscale of GHQ-28 was a factor of higher clinical complexity. ConclusionThe mental state and quality of life are the most important determinants of the clinical complexity in the group of patients with acromegaly whereas the biochemical normalization is of lesser importance.

Systemic infusion of exogenous ghrelin in male broiler chickens (Gallus gallus domesticus). The effect of pulse frequency, doses, and ghrelin forms on feed intake, average daily gain, corticosterone, and growth hormone concentrations

There is limited information on the effect of exogenous ghrelin infusion on feed intake (FI) in chickens. Therefore, male broilers were used in 3 factorial experiments to determine the relationships between doses (0, 1, or 4 nM; Dose), frequency (once every two h; 2 h), once every 4th h (4 h) or continuous infusion, and ghrelin forms including acylated-ghrelin (AG) and desacylated-ghrelin (DAG) on FI, ADG, and concentrations of corticosterone and Growth Hormone (GH). Treatments were delivered via a jugular cannula, using programmable pumps for 11 consecutive days. FI and ADG were recorded, and plasma was collected. Data were analyzed using a factorial design. In Experiment 1 the effect of AG pulse frequency and doses were evaluated. There was a linear decrease in FI (P = 0.002) and a linear increase in corticosterone (P = 0.033) and GH (P = 0.011) concentrations when AG was infused. However, ADG decreased with doses (P = 0.011) only when AG was given at 2 h. In Experiment 2 the effect of ghrelin forms and doses given at 2 h was evaluated. There was a linear decrease in FI when AG was infused and a linear increase in FI when DAG was infused (P < 0.05). Birds infused with DAG gained more weight than those infused with AG. There was a linear increase in corticosterone and GH concentrations only when AG was infused (P < 0.01). In Experiment 3 the effect of continuous infusion of 2 doses (0 and 1 nM) of AG and DAG were evaluated. There was a linear decrease in FI and ADG when AG (P < 0.001) was infused and a linear increase in FI and ADG when DAG was infused (P < 0.05). There was an increase in corticosterone concentrations only when AG was infused (P = 0.022). However, GH concentrations were not affected by treatments. We concluded that AG and DAG pulse frequency and doses had a differential effect on FI, ADG, corticosterone, and GH concentrations in broiler chickens.

REPRODUCTIVE, BIOCHEMICAL, AND HORMONAL TRAITS OF LOCAL QUAIL IN RESPONSE TO DIETARY SUPPLEMENTATION OF DRIED GARLIC POWDER

The study was conducted to find out the effect of dried garlic (Allium sativum) powder at different levels on the productive and reproductive performance of local quail. About ninety female local quail were used. The quails were divided into six groups (control, standard diet + 3% lipid, standard diet + 2% powder garlic, standard diet + 2% powder garlic + 3% lipid, standard diet + 4% powder garlic, and standard diet + 4% powder garlic + 3% lipid). A higher significance (p≤0.05) in egg weight (11.69 g/egg), feed intake (2977.13 g/week), hen day egg production (92.48 %), and egg mass (10.62) was recorded of quail eating (4% powder garlic). The results show the significant (p≤0.05) superiority of quails fed 4% of garlic powder in the internal egg characteristics such as egg albumen weight, yolk height, Haugh unit, and egg hardness. A significant (p≤0.05) improvement in the blood lipid profile in favor of quail birds fed on rations containing dried garlic powder, as the highest value for total cholesterol, triglycerides, LDL, and VLDL found in the treatment of birds fed on high lipids, while the highest values ​​of HDL were in the treatments of fed different levels of garlic powder. The highest levels of Ghrelin, T4, and LH, hormones were recorded for quail birds fed with 2% garlic powder. Birds fed on high lipid diet showed higher concentrations of leptin and growth hormone, while the higher value of FSH was seen in a 4% garlic supplemented diet. We conclude from the above that birds fed 4% dried garlic powder were superior in most productive and reproductive traits, compared to other treated birds.

Effect of yeast culture supplementation on blood characteristics, body development, intestinal morphology, and enzyme activities in geese.

The objective of this experiment is to evaluatethe effects of yeast culture (YC) supplementation on blood characteristics, body size, carcass characteristics, organ weights, intestinal morphology, and enzyme activities. Five groups of geese were randomly assigned to five dietary treatments: the basal diet (control) and basal diets plus 0.5%, 1.0%, 2.0%, or 4.0% YC. Compared with the controls, YC supplementation at 0.5% and 1.0% increased the serum total protein (TP), albumin (ALB), and globulin (GLO) and decreased the uric acidand creatine kinase (CK) contents (p < 0.05). YC supplementation at 2.0% and 4.0% increased the CK, growth hormone, catalase and glutathione reductase contents, and relative proventriculus weights, and decreased the TP, ALB, and GLO contents, relative liver, gizzard, jejunum, ileum, and thymus weights (p < 0.05). YC supplementation at 2.0% improved fossil bone length, breast muscle percentage, jejunal villus height, ileal and jejunal villus height/crypt depth ratios, pepsin, lipase, amylase and pancreatic trypsin activities, and decreased abdominal fat percentage (p < 0.05). Furthermore, YC inclusion increased the body slope length (linear, p = 0.002; quadratic, p = 0.02), breast width (quadratic, p = 0.02), ileal (linear, p = 0.04; quadratic, p = 0.01) and duodenal villus height (cubic, p = 0.04), and decreased the relative gizzard (quadratic, p = 0.04) and thymus (linear, p = 0.002; quadratic, p = 0.02; cubic, p = 0.02) weights, liver (linear, p = 0.002; quadratic, p = 0.02), and serum (linear, p = 0.006; quadratic, p = 0.03) malondialdehyde contents, and jejunal crypt depth (quadratic, p = 0.03). The findings indicated that the YC supplementation had a positive effect on the growth and development of geese, with 2% YC being the most effective.

LEAP2 reduces postprandial glucose excursions and ad libitum food intake in healthy men

SummaryThe gastric hormone ghrelin stimulates food intake and increases plasma glucose through activation of the growth hormone secretagogue receptor (GHSR). Liver-expressed antimicrobial peptide 2 (LEAP2) has been proposed to inhibit actions of ghrelin through inverse effects on GHSR activity. Here, we investigate the effects of exogenous LEAP2 on postprandial glucose metabolism and ad libitum food intake in a randomized, double-blind, placebo-controlled, crossover trial of 20 healthy men. We report that LEAP2 infusion lowers postprandial plasma glucose and growth hormone concentrations and decreases food intake during an ad libitum meal test. In wild-type mice, plasma glucose and food intake are reduced by LEAP2 dosing, but not in GHSR-null mice, pointing to GHSR as a potential mediator of LEAP2’s glucoregulatory and appetite-suppressing effects in mice.

The role of growth hormone and IFR-1 in the formation of leukocytic blood composition in the body of calves during cultivation

Purpose: to evaluate the biological properties of growth hormones (GH, IGF-1) in the dairy and vegetable periods of growing Holsteinized Black-and-White heifers, determined by their ability to regulate the age-related variability of the leukocyte composition of the blood.Materials and methods. The work was carried out in the conditions of the SPK «Koelginskoe» named after V. I. Shundeeva I. N. (Chelyabinsk region) in 2019–2020 on heifers of Holsteinized Black-and-White breed during the dairy and vegetable growing periods. Animals up to 3 months of age were kept individually, and then in groups of 10 animals. Milk and milk replacer were used in the diet of animals only up to 3 months, and then they were transferred to a plant-based diet. When compiling the feeding ration on the farm, they were guided by the norms of the VIZh. The experimental group (n=10) was formed according to the principle of approximate analogues, heifers were included in its composition after a clinical examination, which was carried out later with each blood sampling. For laboratory studies, whole blood and blood serum were used. Blood sampling was performed at 1, 3, 6, 9, 12 and 13 months of age in the morning before feeding. The leukocyte composition of the blood, the concentration of growth hormone and IGF-1 were determined.Results. It was found that the total number of leukocytes in the bloodstream of heifers increases with age by 28.06% (p&lt;0.05), which is accompanied by an increase in the percentage of eosinophils, segmented neutrophils and monocytes in the leukogram by 45.31; 5.70 and 50.00% (p&lt; 0.05), a decrease in lymphocytes, rodshaped neutrophils by 5.69 and 43.39% (p&lt;0.05). The level of STH by the end of the heifer rearing period decreases by 54.32% (p &lt;0.05), and the insulin-like growth factor type 1, on the contrary, increases by 32 times (p&lt;0.05). The values of the correlation coefficients in the statistical matrix of STG and IGF.

Effect of biostimulation on growth rate and reproductive development of Bos indicus dairy heifers.

The present study aimed to compare the growth rate, feeding behavior, reproductive development, and concentrations of GH and leptin in Sahiwal heifers exposed to direct bull contact, bull contact through a fenceline, or isolated from bulls. Overall, 24 heifers were allotted to three treatment groups (n = eight/group) based on birth weight, body weight, and age. Heifers from the non-exposed group (NBE) remained isolated from bulls; heifers stimulated by fenceline bull contact (FBE) remained continuously exposed to bulls through a fenceline, and heifers with direct bull contact (DBE+FBE) had direct contact with a bull during 6 h/day plus continuous fenceline bull exposure for the entire 24 h period. It was considered that heifers attained puberty when progesterone concentration was >1 ng/mL. Biostimulated heifers achieved puberty at both a lower age and body weight (P < 0.05) than NBE heifers. Overall, average daily gain (g/day) was greater in DBE+FBE (516.3 ± 4.5) and FBE (501.6 ± 4.3) than in NBE (441.8 ± 2.9, respectively; P < 0.01). Leptin and growth hormone concentrations were significantly greater in FBE and DBE+FBE than NBE heifers. Both groups of biostimulated heifers devoted more time eating than NBE heifers, P < 0.05). In conclusion, biostimulation of Sahiwal heifers, either by exposing them to bulls through a fenceline or by both fenceline exposure and direct contact, reduced the age of puberty and increased growth performance. Overall, fenceline bull exposure can be recommended as an easy handling management to stimulate reproductive precocity and growth rate in heifers.

Effect of Dietary Betaine on Muscle Protein Deposition, Nucleic Acid and Amino Acid Contents, and Proteomes of Broilers.

Simple SummaryIn animal production, growth trials have shown that betaine has a positive effect on growth performance, especially improving meat yield. Proteins are the largest unit comprising muscle cells except moisture. However, how betaine regulates muscle protein anabolism and abundance levels remains unclear. Therefore, this study was conducted to investigate the effect of dietary betaine on growth performance, muscle protein deposition, and proteome of broilers. The results suggested that betaine could improve growth performance and muscle protein deposition of broilers. Alterations in muscle nucleic acids, amino acids, and protein abundance levels were involved in this process. Proteomic analysis further revealed that 35 proteins in breast muscle were identified as differentially abundant proteins by betaine supplementation, which were mainly related to cell differentiation, small molecule metabolic process, and tissue development.To investigate the effect of betaine supplementation on growth performance, muscle protein deposition, muscle nucleic acid and amino acid contents, and muscle proteome of broilers, 160 one-day-old male partridge shank broiler chickens were randomly divided into 2 groups with 8 replicates of 10 broilers each. Broilers were fed a basal diet alone, or a basal diet supplemented with 1000 mg/kg betaine. Compared with the control group, the betaine group significantly increased (p < 0.05) the broilers average daily gain, the levels of serum insulin-like growth factor-1 (IGF-1), growth hormone (GH), total protein (TP), the contents of muscle absolute protein deposition, RNA, Ser, Glu, Met, and Phe, and the ratio of RNA/DNA, and decreased (p < 0.05) the feed conversion ratio and serum blood urea nitrogen content. Moreover, proteomic analysis revealed 35 differentially abundant proteins (DAPs) in the betaine group compared with the control group, including 27 upregulated proteins and 8 downregulated proteins (p < 0.05). These DAPs were mainly related to cell differentiation, small molecule metabolic process, and tissue development. In conclusion, diets supplemented with 1000 mg/kg betaine improved growth performance and muscle protein deposition of broilers. Increased serum GH, IGF-1, and TP contents, and alterations in muscle nucleic acids, amino acids, and protein abundance levels were involved in this process.

Effects of Different Anesthetic and Analgesic Methods on Cellular Immune Function and Stress Hormone Levels in Patients Undergoing Esophageal Cancer Surgery.

The change of perioperative immune function in patients with esophageal cancer is mainly caused by the joint action of surgical trauma and anesthesia. In our study, we aimed to investigate the effects of different anesthetic methods on the changes of T lymphocyte subsets and cytokines in peripheral blood of patients with esophageal cancer surgery. 50 patients with esophageal cancer were divided into the study group and the control group. Among them, the patients in the control group chose intravenous anesthesia and received self-controlled intravenous analgesia after surgery. Patients in the study group chose thoracic epidural anesthesia combined with general anesthesia, undergoing self-controlled epidural analgesia after surgery; serum interleukin-2 (IL-2) and soluble interleukin-2 receptor (sIL-2R) were measured by ELISA. Serum stress hormones GH and sIL-8 were measured by radioimmunoassay. Both groups of patients achieved significant postoperative analgesia, but the VAS score in the study group at the T2–T4 time point was lower than that in the control group. The serum GH concentration in the study group increased at T1 and reached its highest peak at T2, then decreased. The serum IL-8 concentration of the two groups showed a downward trend from T1 to T4. Thoracic epidural anesthesia combined with general anesthesia for postoperative epidural analgesia can relieve the degree of cellular immunosuppression during and after surgery. Moreover, the thoracic epidural block combined with general anesthesia for esophageal cancer surgery and epidural analgesia after surgery for patients are anesthetic and analgesic methods with clinically significant effects. Our research results have a positive effect on the promotion of postoperative rehabilitation in patients with malignant cell tumors.

Growth hormone isoform testing in capillary dried blood spots: Results from single and multiple dose administration studies and large-scale field collections.

A multiphase study was designed to examine the detectability of human growth hormone (GH) use in capillary dried blood spots (DBS). First, 13 subjects self-injected a single, 2-mg dose of somatropin and collected capillary DBS samples for 24 h. Next, nine subjects self-injected 2-mg somatropin, six times over the course of 11 days; DBS were collected intermittently following dosing. Finally, a nondrug, large-scale field study involved DBS collections from an athlete and staff population over 3 years. All DBS samples were self-collected using the Tasso M20 device and were analyzed for the presence of GH using the WADA-approved GH isoforms test. Following the single dose, positive detection within 12 h of dosing was 86% and 56% sensitive on Kits 1 and 2, respectively. In the multidose study, detection within 12 h was 85% and 69% sensitive on Kits 1 and 2, respectively. No positives were detected outside the 12-h window following a single dose, wherein detection was 5.6% sensitive at 24-h in the multidose study. Combining the 12-h windows from both studies, 100% of samples had measurable recombinant (REC) and pituitary (PIT) GH concentrations above the assay LoD, 0.041 ng/ml. Finally, 1213 samples were collected in the large-scale field study: 189 showed REC and PIT concentrations above the LoD; none returned positive results. GH is detectable in capillary DBS using the isoforms method for 12-24 h following use. While detection is short lived, transitioning to a DBS self-collection method can allow more frequent testing and increase deterrence to GH abuse.

Effects of Exogenous Ghrelin on Feeding, Drinking and Growth Hormone Secretion in African Ostrich Chicks

Background: Ghrelin is widely distributed in an animal’s body, playing important biological roles. In mammals, Ghrelin can stimulate food intake and weight gain, but in poultry, it inhibits food intake and drinking. We aimed to determine the effect of Ghrelin on feeding, drinking, body weight and growth hormone (GH) content of African ostrich chicks. Methods: Sixteen 40-day-old African ostrich chicks were randomly divided into four groups and injected intravenously with saline (control) or Ghrelin (10, 50 and 100 µg/kg) for 7 days. The feeding, drinking and growth hormone (GH) levels using measurement method and radioimmunoassay were determined. Result: The results show that exogenous Ghrelin increased the feed intake rate, the drinking rate and the secretion of GH in the ostriches.

Overactivation of hepatic mechanistic target of rapamycin kinase complex 1 (mTORC1) is associated with low transcriptional activity of transcription factor EB and lysosomal dysfunction in dairy cows with clinical ketosis

Ketosis occurs most frequently in the peripartal period and is associated with liver injury and steatosis. Lysosomes serve as the terminal degradative station and contribute to liver homeostasis through their role in the digestion of dysfunctional organelles and lipid droplets. Transcription factor EB (TFEB) has been identified as a master regulator of lysosomal function. Thus, the objective of the present study was to investigate the status of lysosomal function and TFEB transcriptional activity and potential changes in abundance of upstream effectors of TFEB identified in nonruminants, including mechanistic target of rapamycin kinase complex 1 (mTORC1), protein kinase B (Akt), glycogen synthase kinase β (GSK3β), and extracellular signal-regulated kinase1/2 (ERK1/2), and to explore which factor induces the above changes. Liver and blood samples were collected from healthy cows (n = 10) and ketotic cows (n = 10) that had a similar number of lactations (median = 3, range = 2-4) and days in milk (median = 6 d, range = 3-9 d). Calf hepatocytes were isolated from Holstein calves and treated with 10 ng/mL growth hormone (GH), 3.0 mM β-hydroxybutyrate (BHB), 1.5 ng/mL interleukin-18 (IL-18), 0.15 ng/mL tumor necrosis factor-α (TNF-α), or 1.2 mM free fatty acid (FFA) for 12 h. Serum levels of FFA and activities of alanine aminotransferase and aspartate aminotransferase were greater in ketotic cows, whereas glucose was lower. Additionally, ketotic dairy cows exhibited higher serum concentrations of GH, IL-18, and TNF-α, and lower serum concentration of insulin. The lower protein abundance of lysosome-associated membrane protein 1 (LAMP1) and mRNA abundance of LAMP1 indicated that hepatic lysosomal mass was lower in ketotic cows. Furthermore, lower protein abundance of cathepsin D (CTSD) and mRNA abundance of CTSD and V0 domain of the vacuolar ATPase along with lower activity of β-N-acetylglucosaminidase indicated impairment in hepatic lysosomal function due to ketosis. The lower nuclear abundance, total protein, and mRNA abundance of TFEB and peroxisome proliferator-activated receptor γ coactivator 1 α along with greater phosphorylated (p)-TFEB in the liver of ketotic cows indicated an impairment of hepatic TFEB transcriptional activity. The protein abundances of phosphorylated mTOR (p-mTOR) and its downstream effectors ribosomal protein S6 kinase B (RPS6KB) and eukaryotic factor 4E-binding protein 1 (EIF4EBP1) were greater, whereas p-Akt, p-GSK3β, and p-ERK1/2 were lower in the liver of ketotic cows. Importantly, elevated phosphorylation of mTOR, RPS6KB, and EIF4EBP1 was observed in calf hepatocytes treated with GH, BHB, IL-18, TNF-α, and FFA. Moreover, BHB, TNF-α, and FFA, not GH and IL-18, reduced TFEB transcriptional activity and impaired lysosomal function in calf hepatocytes. Taken together, these data suggest that BHB, TNF-α, and FFA overactivate the hepatic mTORC1 signaling pathway during ketosis and further impaired TFEB transcriptional activity and lysosomal function, which may contribute to liver injury and steatosis.

Genome-wide identification and expression analysis of the MYC transcription factor family and its response to sulfur stress in cabbage (Brassica oleracea L.).

MYC transcriptional factors are members of the bHLH (basic helix-loop-helix) superfamily, and play important roles in plant growth, biological and abiotic stress. Recent studies have revealed that some MYCs are involved in the synthesis of sulfur-containing secondary metabolites. Cabbage, as a typical sulfur-loving crop and rich in sulfur-containing secondary metabolites, the regulatory relationship between sulfur stress and MYC gene family, related reports are relatively rare. In this study, we conducted the first genome-wide analysis of the MYC transcription factor family of cabbage and identified 17 BoMYC genes. Homology of the 17 BoMYC genes, 12 Arabidopsis, 12 Chinese cabbage, 8 wheat and 21 maize MYC were analyzed using the phylogenetic analysis. Meanwhile, chromosome locations, physical and chemical characteristics, gene structures, conserved motif, cis-element, specific expression in different tissues were studied. Finally, we analyzed the expression of the BoMYC gene under sulfur stress and its GO annotation and KEGG enrichment analysis, determined the expression of the BoMYC gene under hormone treatment and the growth index, photosynthetic capacity and hormone content in the leaves. This study is of great significance for functional identification and revealed the effect of S on BoMYC transcription factors.

Effects of Leptin, Growth Hormone and Photoperiod on Pituitary SOCS-3 Expression in Sheep.

Simple SummaryMaintaining energy homeostasis requires numerous processes and interactions between many systems. This study investigated the relationships between leptin, growth hormone (GH), and factors involved in cell signaling, such as suppressors of cytokine signaling-3 (SOCS-3). Exogenous or endogenous factors affecting these relationships may have different origins, and their interactions are determined in this study. The finding that the length of day significantly influenced the concentrations of growth hormone as well as pituitary leptin- and GH-dependent SOCS-3 expressions suggests that photoperiod plays an important role in regulating the physiological processes underlying adaptive phenomena in response to changing seasons in sheep, which facilitates energy homeostasis despite changing external and internal conditions.This study examined how leptin affects growth hormone (GH) release and investigated the effects of leptin, GH, and day length on the suppressor of cytokine signaling-3 (SOCS-3) mRNA levels in the adenohypophyses of sheep. The study consisted of two experiments. The first experiment was conducted during long (LD) and short (SD) days. Within-season and replicate sheep were centrally infused with Ringer-Locke buffer or leptin three times at 60-min intervals at the beginning of experiments. The second experiment involved adenohypophyses collected from sheep that were euthanized in May or November. Pituitary explants were treated with medium alone (Control) or medium with leptin or GH at different concentrations and incubated for various times. The results of the first experiment indicated GH concentrations were seasonally dependent and that leptin had no effect on GH secretion. The results of the second experiment indicated a stronger influence of leptin on the expression of SOCS-3 during the SD season than the LD season. During SDs, significant effects of both GH doses on SOCS-3 expression were observed. These results indicate a strong association between leptin, GH, and SOCS-3, which may explain the disruption of SOCS-3 leptin and GH signaling and the dominant effect of photoperiod on the above relationships.

Role of pulsatile growth hormone (GH) secretion in the regulation of lipolysis in fasting humans

BackgroundThe increase in growth hormone (GH) secretion during a prolonged fast stimulates lipolytic rate, thereby augmenting the mobilization of endogenous energy at a time when fuel availability is very low.Study aimTo identify the specific component of GH secretory pattern responsible for the stimulation of lipolytic rate during fasting in humans.Study protocolWe measured lipolytic rate (using stable isotope dilution technique) after an overnight fast in 15 young, healthy, non-obese subjects (11 men and 4 women), and again on four separate occasions after a 59 h fast. These four prolonged fasting trials differed only by the contents of an infusion solution provided throughout the 59 h fasting period. Subjects were infused either with normal saline (“Control”; n = 15) or with graded doses of a GH Releasing Hormone Receptor Antagonist (GHRHa):10 μg/kg/h (“High”; n = 15), 1 μg /kg/h (“Medium”; n = 8), or 0.5 μg /kg/h (“Low”; n = 6).ResultsAs expected, the 59 h fast completely suppressed plasma insulin levels and markedly increased endogenous GH concentrations (12 h vs 59 h Fast; p = 0.0044). Administration of GHRHa induced dose-dependent reduction in GH concentrations in response to the 59 h fast (p < 0.05). We found a strong correlation between the rate of lipolysis and GH mean peak amplitude (R = 0.471; p = 0.0019), and total GH pulse area under the curve (AUC) (R = 0.49; p = 0.0015), but not the GH peak frequency (R = 0.044; p = 0.8) or interpulse GH concentrations (R = 0.25; p = 0.115).ConclusionDuring prolonged fasting (i.e., 2–3 days), when insulin secretion is abolished, the pulsatile component of GH secretion becomes a key metabolic regulator of the increase in lipolytic rate.

Thyroid disruption and growth inhibition of zebrafish embryos/larvae by phenanthrene treatment at environmentally relevant concentrations.

Phenanthrene induces reproductive and developmental toxicity in fish, but whether it can disrupt the thyroid hormone balance and inhibit growth had not been determined to date. In this study, zebrafish embryos were exposed to phenanthrene (0, 0.1, 1, 10 and 100μg/L) for 7 days. The results of this experiment demonstrated that phenanthrene induced thyroid disruption and growth inhibition in zebrafish larvae. Phenanthrene significantly decreased the concentration of l-thyroxine (T4) but increased that of 3,5,3'-l-triiodothyronine (T3). The expression of genes related to the hypothalamic-pituitary-thyroid (HPT) axis was altered in zebrafish larvae exposed to phenanthrene. Moreover, phenanthrene exposure significantly increased the malformation rate and significantly reduced the survival rate and the body length of zebrafish larvae. Furthermore, phenanthrene significantly decreased the concentrations of growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Changes observed in gene expression patterns further support the hypothesis that these effects may be related to alterations along the GH/IGF-1 axis. In conclusion, our study indicated that exposure to phenanthrene at concentrations as low as 0.1μg/L resulted in thyroid disruption and growth inhibition in zebrafish larvae. Therefore, the estimation of phenanthrene levels in the aquatic environment needs to be revisited.

A Case of Persistent Hypoglycemia with Disorder of Sex Development

A Case of Persistent Hypoglycemia with Disorder of Sex Development

Magneto-Immunoassay for the Detection and Quantification of Human Growth Hormone.

Physiological and endocrine maintenance of a normal human growth hormone (hGH) concentration is crucial for growth, development, and a number of essential biological processes. In this study, we describe the preparation and characterization of magnetic nanoparticles coated with a gold shell (MNPs-Au). The optimal surface concentration of monoclonal anti-hGH antibodies (m-anti-hGH) on magnetic nanoparticles, as well as conditions that decrease non-specific interactions during the magneto-immunoassay, were elaborated. After the selective recognition, separation, and pre-concentration of hGH by MNPs-Au/m-anti-hGH and the hGH interaction with specific polyclonal biotin-labeled antibodies (p-anti-hHG-B) and streptavidin modified horseradish peroxidase (S-HRP), the MNPs-Au/m-anti-hGH/hGH/p-anti-hGH-B/S-HRP immunoconjugate was formed. The concentration of hGH was determined after the addition of 3,3′,5,5′-tetramethylbenzidine and hydrogen peroxide substrate solution for HRP; the absorbance at 450 nm was registered after the addition of STOP solution. The developed sandwich-type colorimetric magneto-immunoassay is characterized by a clinically relevant linear range (from 0.1 to 5.0 nmol L−1, R2 0.9831), low limit of detection (0.082 nmol L−1), and negligible non-specific binding of other antibodies or S-HRP. The obtained results demonstrate the applicability of the developed magneto-immunoassay for the concentration and determination of hGH in the serum. Additionally, important technical solutions for the development of the sandwich-type colorimetric magneto-immunoassay are discussed.

Effects of globular and flexible structures on the emulsifying and interfacial properties of mixed soy proteins

In mixed protein system, the emulsifying and interfacial properties are affected by the composition and conformation of different proteins. To clarify the underlying mechanism, β-conglycinin and hydrolysates of glycinin (GH) were used as globular and flexible proteins, and the structural and functional properties of mixed proteins with different ratios were investigated. As GH content increased, the amount of β-sheet decreased significantly, whereas α-helix, β-turn, and random coil contents increased, which indicated the intramolecular structural flexibility of mixed soy protein was slightly reduced, whereas the intermolecular structural flexibility improved substantially. Interfacial shear rheology was used to assess the linear and nonlinear behavior of mixed soy proteins at the interface. As GH content increased, the elastic modulus was decreased while the width of the linear viscoelastic region (LVR) was slightly increased. For all samples, when small strain amplitudes were at 1–10% (within the LVR), the shape of the elastic Lissajous plots was perfectly elliptical. The elliptical shape changed to circular as strain increased. Compared with single 7S, the mixed soy proteins showed reduced levels of deformation in the elliptical shape, which were likely due to the greater resistance of the gelatinous network and its ability to resist permanent deformation. The particle size, zeta-potential, interfacial protein adsorption fraction, microstructure, and stability of emulsions formed of mixed soy proteins were also studied. Results showed that emulsion formed of mixed soy proteins with a ratio of 1:1 (GH-50%) was optimal. This study could potentially aid in the application of proteins with different structures and interfacial properties in emulsion.

Effect of circadian system disruption on the concentration and daily oscillations of cortisol, progesterone, melatonin, serotonin, growth hormone, and core body temperature in periparturient dairy cattle

Metabolic, circadian, sleep, and reproductive systems are integrated and reciprocally regulated, but the understanding of the mechanism is limited. To study this integrated regulation, the circadian timing system was disrupted by exposing late pregnant nonlactating (dry) cows to chronic shifts in the light-dark phase, and rhythms of body temperature and circulating cortisol (CORT), progesterone (P4), serotonin (5HT), melatonin (MEL), and growth hormone (GH) concentrations were measured. Specifically, across 2 identical studies (1 and 2), at 35 d before expected calving (BEC) multiparous cows were assigned to control (CON; n = 24) and exposed to 16 h light and 8 h dark or phase shift (PS; n = 24) treatments and exposed to 6-h light-dark phase shifts every 3 d until parturition. All cows were exposed to control lighting after calving. Blood samples were collected in the first study at 0600 h on d 35 BEC, d 21 BEC, and 2 d before calving, and d 0, 2, 9, 15, and 22 postpartum (PP). A subset of cows (n = 6/group) in study 1 was blood sampled every 4 h over 48 h beginning on d 23 BEC, 9 BEC, and 5 PP. Body temperature was measured every 30 min (n = 8-16/treatment) for 48 h at 23 BEC and 9 BEC in both studies; and at 14 PP and 60 PP only in study 2. Treatment did not affect levels of CORT, GH, or P4 at 0600 h, but overall level of 5HT was lower and MEL higher in PS cows across days sampled. A 2-component versus single-component cosinor model better described [>coefficient of determination (R2); <Akaike information criterion and <Bayesian information criterion] daily oscillations of all hormones and temperature for both treatments. Circadian rhythm fit (R2) of body temperature and MEL increased from 23 BEC to 9 BEC in CON and was marked by loss of feeding time influence on oscillations in both treatments. Both treatments exhibited circadian rhythms of CORT at 9 BEC, CON cows also exhibited circadian rhythms in P4 at 23 BEC, and 5HT at 9 BEC. Daily oscillations in temperature and hormones, except CORT, were affected by PS treatment in the prepartum and were associated with longer gestation. In the PP, circadian rhythmicity was lost or diminished for all hormones and body temperature in both treatments. Stronger rhythms of body temperature and multiple hormones at 1 wk prepartum may indicate a synchronizing cue to time parturition. Therefore, dairy systems may need to consider management factors that affect circadian clocks in late-gestation cows.