Insulin-like Growth Factor Igf Research Articles

Two pathways regulate insulin-like growth factor genes in the brain and liver of the tropical damselfish Chrysiptera cyanea: A possible role for melatonin in the actions of growth and thyroid hormones

External and internal factors are involved in controlling the growth of fishes. However, little is known about the mechanisms by which external factors trigger stimulus signals. This study explored the physiological roles of melatonin in the transcription of growth-related genes in the brain and liver of Chrysiptera cyanea, a tropical damselfish with long-day preference. In brain samples of this species collected at 4-h intervals, the transcript levels of arylalkylamine N-acetyltransferase2 (aanat2), the rate-limiting enzyme of melatonin synthesis, and growth hormone (gh) peaked at 20:00 and 00:00, respectively. Concomitantly, the transcript levels of insulin-like growth factors (igf1 and igf2) in the brain and liver were upregulated during the scotophase. Levels of iodothyronine deiodinases (dio2 and dio3), enzymes that convert thyroxine (T4) to triiodothyronine (T3) and reverse T3, respectively, increased in the brain (dio2 and dio3) and liver (dio2) during the photophase, whereas dio3 levels in the liver showed the opposite trend. Fish reared in melatonin-containing water exhibited significant increases in the transcription levels of gh and igf1 in the brain and igf1 in the liver, suggesting that growth in this fish is positively regulated by the GH/IGF pathway on a daily basis. Melatonin treatment also stimulated the transcript levels of dio2 and dio3 in the liver, but not in the brain. Fish consuming pellets containing T3, but not T4, showed significant increases in gh and igf1 in the brain and igf1 and igf2 in the liver, suggesting that the intercellular actions of the TH/IGF pathway have an impact on growth on a daily basis. In summary, IGF synthesis and action in the brain and liver undergo dual regulation by distinct hormone networks, which may also be affected by daily, seasonal, or nutritional factors.

Handelin alleviates cachexia- and aging-induced skeletal muscle atrophy by improving protein homeostasis and inhibiting inflammation.

Handelin is a bioactive compound from Chrysanthemum indicum L. that improves motor function and muscle integrity during aging in Caenorhabditis elegans. This study aimed to further evaluate the protective effects and molecular mechanisms of handelin in a mouse muscle atrophy model induced by cachexia and aging. A tumour necrosis factor (TNF)-α-induced atrophy model was used to examine handelin activity in cultured C2C12 myotubes in vitro. Lipopolysaccharide (LPS)-treated 8-week-old model mice and 23-month-old (aged) mice were used to examine the therapeutic effects of handelin on cachexia- and aging-induced muscle atrophy, respectively, in vivo. Protein and mRNA expressions were analysed by Western blotting, ELISA and quantitative PCR, respectively. Skeletal muscle mass was measured by histological analysis. Handelin treatment resulted in an upregulation of protein levels of early (MyoD and myogenin) and late (myosin heavy chain, MyHC) differentiation markers in C2C12 myotubes (P<0.05), and enhanced mitochondrial respiratory (P<0.05). In TNF-α-induced myotube atrophy model, handelin maintained MyHC protein levels, increased insulin-like growth factor (Igf1) mRNA expression and phosphorylated protein kinase B protein levels (P<0.05). Handelin also reduced atrogin-1 expression, inhibited nuclear factor-κB activation and reduced mRNA levels of interleukin (Il)6, Il1b and chemokine ligand 1 (Cxcl1) (P<0.05). In LPS-treated mice, handelin increased body weight (P<0.05), the weight (P<0.01) and cross-sectional area (CSA) of the soleus muscle (P<0.0001) and improved motor function (P<0.05). In aged mice, handelin slightly increased the weight of the tibialis anterior muscle (P=0.06) and CSA of the tibialis anterior and gastrocnemius muscles (P<0.0001). In the tibialis anterior muscle of aged mice, handelin upregulated mRNA levels of Igf1 (P<0.01), anti-inflammatory cytokine Il10 (P<0.01), mitochondrial biogenesis genes (P<0.05) and antioxidant-related enzymes (P<0.05) and strengthened Sod and Cat enzyme activity (P<0.05). Handelin also reduced lipid peroxidation and protein carbonylation, downregulated mRNA levels of Fbxo32, Mstn, Cxcl1, Il1b and Tnf (P<0.05), and decreased IL-1β levels in serum (P<0.05). Knockdown of Hsp70 or using an Hsp70 inhibitor abolished the ameliorating effects of handelin on myotube atrophy. Handelin ameliorated cachexia- and aging-induced skeletal muscle atrophy in vitro and in vivo, by maintaining homeostasis of protein synthesis and degradation, possibly by inhibiting inflammation. Handelin is a potentially promising drug candidate for the treatment of muscle wasting.

Use of black soldier fly (Hermetia illucens) larvae meal in diets for gilthead seabream juveniles: Effects on growth-related gene expression, intermediary metabolism, digestive enzymes, and gut microbiota modulation

A study was conducted to evaluate the effects of dietary inclusion of defatted Hermetia illucens larvae meal (HM) on the expression of growth-related genes, plasma metabolites, activity of intermediary metabolism enzymes, and gut microbiota modulation in gilthead seabream (Sparus aurata) juveniles. Four experimental diets were formulated (43% crude protein, 18% crude lipids) with increasing levels of defatted HM: 0 (HM0), 15 (HM15), 30 (HM30), and 45% (HM45) replacing fishmeal (included at 34% in the control diet) at 0, 22, 60, and 100%, respectively. Fish were fed these diets for 67 days. At the end of the trial, the expression of muscle growth hormone receptors (ghr1 and ghr2), insulin-like growth factors (igf1 and igf2), cathepsins (cts-a and cts-b), and myogenic determination factor 1 (myod1) were not affected, while a downregulation of myogenic determination factor 2 (myod2) and upregulation of myostatin (mstn) was observed with HM inclusion. Plasma metabolites profile was unaffected by diet composition, except for a linear decrease trend in total lipids. A linear increase of liver alanine aminotransferase (ALT) and glutamate dehydrogenase (GDH) activity and a linear decrease of glucose 6-phosphate dehydrogenase (G6PDH), malic enzyme (ME), and (FAS) activity were observed with HM inclusion. The activity of β-hydroxy acyl-CoA dehydrogenase (HOAD) followed a quadratic trend, being higher in fish fed with diet HM15 than in the control. Likewise, amylase, trypsin, and chymotrypsin activity were higher in the posterior intestine of fish fed with diet HM15. Digesta of fish fed the HM-containing diets showed an increase in the number of operational taxonomic units, microbial richness, and diversity. Conversely, a reduction in these indexes was observed in the mucosa. Among the identified bacteria, Firmicutes represented the predominant phyla. The inclusion of HM increased the abundance of Oceanobacillus, Lederbergia, Bacillus, and Corynebacterium in the digesta while Lactobacillus and Caldalkalibacillus abundance was reduced. Overall, total FM replacement with defatted HM had no major effects on plasma metabolites and muscle growth-related genes but induced a few differences in intermediary metabolism and digestive enzymes activity. HM inclusion improved gut digesta microbiota richness and diversity, promoting the growth of potential beneficial bacteria.

FEATURES OF METABOLISM AND THE POTENTIAL ROLE OF NEUROTROPHIC FACTORS OF THE BRAIN IN THE REHABILITATION PROCESS

Understanding the metabolic pathways of regulation and interaction of neurotrophic factors is interesting from the point of view of discussing neurotrophic factors as biological markers reflecting the dynamics and effectiveness of the rehabilitation process. The purpose was to analyze the features of production, metabolism, mechanisms of action of neurotrophic factors, which can explain the possibility of active involvement of the main neurotrophic factors in the rehabilitation process. The article presents an analysis of the literature on the metabolism of brain-derived neurotrophic factors (brain growth factor BDNF, neurotrophins NT-3 and NT4/5, fibroblast growth factor FGF-1 and FGF-2, nerve growth factor NGF, insulin-like growth factor IGF1, glial neurotrophic factor GDNF, ciliary neurotrophic factor CNTF). Information is given about the features of their production, the relationship between profactors and mature forms, as well as the specifics of interaction with receptors.&#x0D; Conclusion. A statistically significant drop in the levels of neurotrophic factors during the rehabilitation therapy of children with cerebral palsy using the «exohand-2» software and hardware complex reflects the active involvement of neurotrophic factors in these processes. The spectrum of biological effects of neurotrophic factors allows us to consider the entire multicomponent mechanism that occurs in the brain in the process of functional restructuring as sufficient for rehabilitation recovery.

Implications on growth performance, glucose metabolism, PI3K/AKT pathway, intestinal flora induced by dietary taurine in a high-carbohydrate diet for grass carp (Ctenopharyngodon idella).

An 8-week experiment was performed to investigate the influence on growth performance, plasma biochemistry, glucose metabolism and the insulin pathway of supplementation of dietary taurine to a high-carbohydrate diet for grass carp. In this study, fish were fed diets at one of two carbohydrate levels, 31·49 % (positive control) or 38·61 % (T00). The high-carbohydrate basal diet (T00), without taurine, was supplemented with 0·05 % (T05), 0·10 % (T10), 0·15 % (T15) or 0·20 % (T20) taurine, resulting in six isonitrogenous (30·37 %) and isolipidic (2·37 %) experimental diets. The experimental results showed that optimal taurine level improved significantly weight gain, specific growth rate (SGR), feed utilisation, reduced plasma total cholesterol levels, TAG and promoted insulin-like growth factor level. Glucokinase, pyruvate kinase and phosphoenolpyruvate carboxykinase activities showed a quadratic function model with increasing dietary taurine level, while hexokinase, fatty acid synthetase activities exhibited a positive linear trend. Optimal taurine supplementation in high-carbohydrate diet upregulated insulin receptor (Ir), insulin receptor substrate (Irs1), phosphatidylinositol 3-kinase (pi3k), protein kinase B (akt1), glycogen synthase kinase 3 β (gs3kβ) mRNA level and downregulated insulin-like growth factor (igf-1), insulin-like growth factor 1 receptor (igf-1R) and Fork head transcription factor 1 (foxo1) mRNA level. The above results suggested that optimal taurine level could improve growth performance, hepatic capacity for glycolipid metabolism and insulin sensitivity, thus enhancing the utilisation of carbohydrates in grass carp. Based on SGR, dietary optimal tributyrin taurine supplementation in grass carp was estimated to be 0·08 %.

The influence of insulin-like growth factor IGF-1 on the course of acne vulgaris

Finding the cause of acne is a key aspect to improve skin appearance and eliminating the problem completely. Due to the multitude of origins and their coexistence, acne treatment is in most cases long-lasting and cannot be limited to one action. Increasing importance in the occurrence and course of acne vulgaris is paid to the high glycemic index of consumed food and insulin-like growth factor (IGF-1). IGF-1 receptors are located on keratinocytes and in acne patients their elevated expression in the epidermis and sebaceous glands is noticed. High levels of IGF-1 are observed in adolescents, as well as in adult women struggling with late acne affecting people over 30 (Acne tarda). It is suspected that it is not androgens, but IGF-1, that is the key element in the appearance and course of Acne vulgaris.

Pharmacokinetics and neurotropic effects of cyclo-L-prolylglycine and its modified analogues

The review presents the results of studies on the pharmacokinetics, metabolism, and bioavailability of new neurotropic dipeptide cyclo-Lprolilglycine (CPG) and their pharmacological activity. It was shown that the pharmacologically active metabolite of the nootropic drug noopept cyclo-Lprolilglycine (CPG) is an endogenous dipeptide, it is a fragment of the terminal Tripeptide of the insulin-like nerve growth factor IGF-1. Much attention is paid both in Russia and abroad to the development of modified CPG analogues with improved pharmacokinetic properties, enzymatically more stable, better penetrating the BBB, and highly effective when used in micromolar doses. CPG shows neuroprotective activity in ischemic-hypoxic and other brain injuries, in addition, it has a complex of other pharmacological effects and therefore CPG can be considered not only as a potential drug, but also as a basic structure for the development of new neurotropic drugs – analogs of CPG with improved pharmacokinetic properties, greater enzymatic resistance and higher bioavailability for the central nervous system.

QS10: The Lysosomal Trafficking Regulator (LYST) Protein is a Novel and Essential Mediator of Cutaneous Wound Healing

Purpose:In 2009, chronic wounds were a major public health threat affecting 2% of the population, and the estimated cost of caring for the 6.5 million people in the U.S. with chronic wounds was 50 billion dollars per year [1]. By 2019, 8.2 million people were wound care patients amongst Medicare beneficiaries, with a higher cost range for care of 28.1 - 96.8 billion dollars [2]. This prevalence and cost burden highlight the increasing nature of the chronic wound problem. Despite the biologic complexity and phylogenetic conservation, basic understanding of wound biology has been limited to relatively few specific fields of study. Little is known about how entire organelle systems, such as endolysosomal-mediated protein trafficking, regulate cutaneous wound healing.Methods:We have uncovered a novel and essential regulator of cutaneous wound healing; the Lysosomal Trafficking Regulator (LYST). LYST is a widely expressed gene encoding a protein that regulates intracellular protein trafficking from secretory lysosomes, but the mechanisms underlying its function are unknown. The Beige mouse model possesses a spontaneously occurring mutation in the LYST gene. We utilized a splinted, excisional wound model to characterize wound healing in the Beige mouse to evaluate the role of LYST in normal wound healing.Results:We observed a significant delay to healing (13.7 +/- 1.0 days, C57Bl/6 vs. 16.7 +/- 2.1 days, Beige, p = 0.0098), decreased extracellular matrix (ECM) deposition (60.8 +/- 10.5% collagen density, C57Bl/6 vs. 50.5 +/- 9.9% collagen density, Beige, p = 0.0321), and delayed epithelialization (94.6 +/- 17.1% epithelialized, C57Bl/6 vs. 58.5 +/- 30.0% epithelialized, Beige, p = 0.0044) in Beige wounds. No differences were observed for macrophage infiltration, phenotype or neovascularization. Next, we evaluated protein secretion profiles from primary dermal fibroblasts from Beige and C57Bl/6 mice. Beige fibroblasts demonstrated decreased ability to secrete monocyte chemoattractant protein-1 (MCP-1) (17294 +/- 563 relative optical density (OD), C57Bl/6 vs. 10519 +/- 2348 relative OD, Beige, p = 0.0083) and members of the insulin-like growth factor regulatory axis, IGF-1 and IGFBP2 (IGF-1; 473.8 +/- 40.6 relative OD, C57Bl/6 vs. 149.8 +/- 133.7 relative OD, Beige, p = 0.0159 and IGFBP2; 17918 +/- 664 relative OD, C57Bl/6 vs. 15451 +/- 690 relative OD, Beige, p = 0.0111). While these are known mediators for normal wound healing, specifically, for wound epithelialization and ECM deposition [3-5], the role of LYST in their intracellular protein trafficking and exocytosis has not been previously described. Interestingly, IGF-1 does rely on well-established exocytic pathways reliant on the synaptotagmin family of proteins [6]. These findings, therefore, provide new insight into the intracellular mechanism of action of the LYST protein, which has previously remained elusive.Conclusions:LYST is important for the secretion of chemokines and growth factors that play an important role in regulating normal wound healing. The expansion of knowledge towards a fundamental understanding of diverse cellular processes involved in normal wound healing, such as endolysosomal trafficking, is important because it provides new lines of investigation for therapeutic strategies to address problem wounds.

Phospholipids improve the performance, physiological, antioxidative responses and, lpl and igf1 gene expressions in juvenile stellate sturgeon (Acipenser stellatus)

The effects of dietary phospholipids (PL) on the performance of juvenile stellate sturgeon (Acipenser stellatus) was evaluated in terms of growth and feed efficiency parameters, muscle and liver fatty acid profiles, activity of digestive and antioxidative stress enzymes, and expression of lipoprotein lipase (lpl) and insulin-like growth factor (igf1). For this purpose, seven isoproteic (44% crude protein) and isolipidic (17% crude fat) diets containing graded levels of soybean lecithin (0, 1, 2, 4, 6, 8 and 10%) were prepared, resulting in 0.3, 0.9, 1.6, 2.7, 3.9, 5.3 and 5.4% of dietary PLs, respectively. At the end of the nutritional study (75 days), we found that there was a positive quadratic polynomial response between growth performance parameters and dietary PLs; somatic growth increased with increasing dietary PL levels up to 3.9% when growth parameters remained stable. Dietary PLs reduced the accumulation of fat stores in the liver and up-regulated the expression of the lipoprotein lipase gene, confirming the important role of this enzyme in incorporating plasma lipids into tissues, whereas the activities of CAT and SOD showed a positive linear increase with dietary PL levels. Increasing dietary PLs from 0.9 to 3.9% promoted the activity of gastric (pepsin) and pancreatic (trypsin, chymotrypsin, bile salt-activated lipase and α-amylase) enzymes, whereas higher inclusion levels of PLs did not provide any advantage in terms of A. stellatus digestive capacities. The analysis of fatty acid profiles in diets and selected tissues (liver and muscle) showed the capacity of A. stellatus juveniles to desaturate and elongate linoleic (C18:2n–6) and alpha-linolenic (C18:3n–3) acids to arachidonic (C20:4n-6), eicosapentaenoic (C20:5n-3) and docosahexaenoic (C22:6n-3) acids. Based on the results of growth performance, feed efficiency and physiological parameters, the inclusion of 3.9% of PLs in compound diets for juvenile stellate sturgeon are recommended.

Effects of acclimation temperature regime on the thermal tolerance, growth performance and gene expression of a cold-water fish, Schizothorax prenanti.

Acclimation temperature is crucial for the optimization of a condition in aquaculture; we experimentally investigated the effects of temperature acclimation on the thermal tolerance, growth performance and gene expression levels of heat shock proteins (hsp70), growth hormone (gh) and insulin-like growth factors (igf-1) in Schizothorax prenanti, a cold-water fish in the Yangtze River basin. Critical thermal maximum (CTmax), critical thermal minimum (CTmin), lethal thermal maximum (LTmax), lethal thermal minimum (LTmin), feeding intake (FI), feeding efficiency (FE), and specific growth rate (SGR) were assessed at three stable temperatures (17, 22 and 27°C) and one variable temperature (22±5°C) for 28d. Better growth performance was observed under variable treatment compared to stable treatments. However, fish under the 27°C treatment exhibited much weaker growth performance than those in the 17°C treatment. Fish under variation temperature treatment fed like those under 22°C treatment; the fish exhibited similar SGR but a higher gh and hsp70 level under variation temperature treatment. This may be due in part to a trade-off energy expenditure to deal with the temperature fluctuation. Together, these findings suggest that juvenile Schizothorax prenanti are resilient to daily fluctuations within the temperature tested here.

Salinity, Temperature and Ammonia Acute Stress Response in Seabream (Sparus aurata) Juveniles: A Multidisciplinary Study.

Simple SummaryGilthead seabream (Sparus aurata) is a teleost fish of great relevance in marine aquaculture, especially in the Mediterranean area and one of the most important farmed food marine species in Europe. Nevertheless, in captivity fish are usually exposed to stressful conditions, with a consequent negative impact on animal welfare and growth. The principal goal of this study was to shed light on the acute stress response of gilthead seabream juveniles exposed to different stressors using a multidisciplinary approach. For this purpose, gilthead seabream have been exposed to three different stress tests (temperature, salinity, and ammonia changes) and several laboratory techniques have been used to evaluate their growth and stress response. Results revealed that all the tested stressors had an impact on fish growth and health, particularly thermic and chemical exposure, whereas salinity seems to have a minor effect since this species can efficiently face with extreme variations in environmental salinity. The present work aimed to obtain relevant information on acute stress response of gilthead seabream to be used for improving farming condition and ensuring fish welfare.The present study aimed to investigate the acute response of gilthead seabream (Sparus aurata) juveniles exposed to temperature, salinity and ammonia stress. Radioimmunoassay was used to evaluate cortisol levels, whereas insulin-like growth factors (igf1 and igf2), myostatin (mstn), heat-shock protein 70 (hsp70) and glucocorticoid receptor (gr) gene expression was assessed trough Real-Time PCR. The presence and localization of IGF-I and HSP70 were investigated by immunohistochemistry. In all the stress conditions, a significant increase in cortisol levels was observed reaching higher values in the thermic and chemical stress groups. Regarding fish growth markers, igf1 gene expression was significantly higher only in fish subjected to heat shock stress while, at 60 min, igf2 gene expression was significantly lower in all the stressed groups. Temperature and ammonia changes resulted in a higher mstn gene expression. Molecular analyses on stress response evidenced a time dependent increase in hsp70 gene expression, that was significantly higher at 60 min in fish exposed to heat shock and chemical stress. Furthermore, the same experimental groups were characterized by a significantly higher gr gene expression respect to the control one. Immunostaining for IGF-I and HSP70 antibodies was observed in skin, gills, liver, and digestive system of gilthead seabream juveniles.

Molecular identification, tissue distribution and in vitro functional analysis of growth hormone and its receptors in red-spotted grouper (Epinephelus akaara).

Red-spotted grouper (Epinephelus akaara) is one of the high economic value grouper species, however, the knowledge regarding its growth is limited. In this study, full-length cDNAs of growth hormone (gh) and its receptors (ghr1 and ghr2) were cloned from the pituitary and liver of red-spotted grouper, respectively. Tissue distribution analysis showed that gh mRNA was predominantly expressed in the pituitary. ghr1 mRNA was highly expressed in the liver, muscle, fat and gonad, while ghr2 mRNA expression was ubiquitously high in the peripheral tissues. However, the mRNA expression of both ghr isoforms was relatively low in the central nervous system. Secretory recombinant grouper GH (rgGH) was expressed in yeast Pichia pastoris and verified. HEK293T cells transiently transfected with the GHR isoforms were used to elucidate the receptor-mediated signaling pathways related to growth regulation. rgGH activated rapid phosphorylation of Janus kinase 2, signal transducer and activator of transcription 5 (STAT5) and extracellular signal-regulated protein kinase 1/2 through GHR1, but only STAT5 was phosphorylated via GHR2. rgGH strongly activated STAT5 phosphorylation and significantly stimulated ghr1, ghr2 and insulin-like growth factor (igf1, igf2) mRNA expression in primary cultured hepatocytes. Data showed that the recombinant protein rgGH played effects on igf1/2 mRNA expression via GHR-mediated signaling pathways. Our findings provide essential information about GH and GHRs characteristics in red-spotted grouper.

Validation of WINROP (online prediction model) to identify severe retinopathy of prematurity (ROP) in an Australian preterm population: a retrospective study.

Retinopathy of prematurity (ROP) is the most common disease leading to blindness in extreme preterm infants. Current screening guidelines recommend frequent eye examinations. There is a dearth of trained ophthalmologists for these frequent screening procedures. The ANZNN neonatal network report (2013) found that only 6.4% of all screened infants had severe ROP and less than half received treatment. WINROP (online prediction model, Sweden) uses the postnatal weight gain (surrogate marker for low insulin-like growth factor IGF-1 and poor retinal vascular growth) to identify ROP requiring treatment and aims to reduce the number of examinations. Our objective was to validate the WINROP model in an Australian cohort of preterm infants. Birth weight, gestational age, and weekly weight measurements were retrieved retrospectively along with the final ROP outcomes and plotted on the online WINROP software. The sensitivity, specificity, positive predictive value, and negative predictive value of WINROP were 85.7%, 59.0%, 6.98%, and 99.1% respectively for a cohort of 221 preterm infants (Median birth weight, 1040 g; Gestational age, 27.9 weeks). WINROP alarm was signaled in 42.6% of all infants. WINROP did not signal an alarm in one infant who needed treatment. This infant had intra ventricular hemorrhage grade 3-4 and temporary ventricular dilatation. This is the first Australian study validating WINROP model. Our findings suggest that it lacked sensitivity to be used alone. However, adjusting the algorithm for the Australian population may improve the efficacy and reduce the number of examinations when used along with the current screening guidelines.

Expression profiles of growth-related genes in two Nile tilapia strains and their crossbred provide insights into introgressive breeding effects.

The Nile tilapia (Oreochromis niloticus) is a prominent farmed fish in aquaculture worldwide. Crossbreeding has recently been carried out between the Red-Stirling and the wt Chitralada strains of Nile tilapia, producing a heterotic hybrid (7/8 Chitralada and 1/8 Red-Stirling) that combines the superior growth performance of the Chitralada with the reddish coloration of the Red-Stirling strain. While classical selective breeding and crossbreeding strategies are well known, the molecular mechanisms underlying the phenotypic expression of economically advantageous traits in tilapia remain largely unknown. Molecular investigations have shown that variable expression of growth hormone (gh), insulin-like growth factors (igf1 and 2) and somatolactin (smtla) - components of the growth hormone/insulin-like growth factor (GH/IGF) axis - and myostatin (mstn) genes can affect traits of economic relevance in farmed animals. The aim of this study was to assess and compare the gene expression signature among Chitralada, Red-Stirling and their backcross hybrid in order to gain insights into the effects of introgressive breeding in modulation of the GH/IGF axis. Gene expression analyses in distinct tissues showed that most genes of the GH/IGF axis were up-regulated and mstn was down-regulated in backcross animals in comparison with Red-Stirling and Chitralada animals. These gene expression profiles revealed that backcross animals displayed a distinctive expression signature, which attests to the effectiveness of the introgressive breeding technique. Our findings also suggest that the GH/IGF axis and mstn genes might be candidate markers for fish performance and prove useful within genetic improvement programs aimed at the production of superior-quality tilapia strains using introgressive breeding.

ГОРМОНАЛЬНЫЙ СОСТАВ МОЛОКА ПРОДУКТИВНЫХ ЖИВОТНЫХ И ЕГО БЕЗОПАСНОСТЬ ДЛЯ ЧЕЛОВЕКА

Hormones are an integral part of milk and throughout lactation, the content of certain hormones is unstable. Hormones regulate the process of starting lactation of animals, the lactation process itself, and also the other functions of the body. Milk is of great importance for the growth of young animals and the formation of immunity. Milk is a special product in the diet and is an important food and raw material for the production of dairy products for people. It contains a large amount of protein, fat, carbohydrates, vitamins and trace elements in biologically available form. But at the same time, over the past few years, more and more evidence has emerged that hormones in dairy products can impact on human health. Thus, some estrogens and insulin-like growth factor IGF-1 are involved in the initiation and provocation of breast, prostate and endometrial tumors. That’s why, it is necessary to normalize and control the content of certain hormones in milk with highly sensitive methods.

A novel epitope-presenting thermostable scaffold for the development of highly specific insulin-like growth factor-1/2 antibodies

High sequence and structural homology between mature human insulin-like growth factors IGF-1 and IGF-2 makes serological discrimination by immunodiagnostic IGF tests a challenging task. There is an urgent need for highly specific IGF-1 and IGF-2 antibodies, yet only a short sequence element, i.e. the IGF loop, provides enough difference in sequence to discriminate between the two molecules. We sought to address this unmet demand by investigating novel chimeric immunogens as carriers for recombinant peptide motif grafting. We found Thermus thermophilus sensitive to lysis D (SlyD) and Thermococcus gammatolerans SlyD FK-506–binding protein (FKBP) domains suitable for presentation of the predefined epitopes, namely the IGF-1 and IGF-2 loops. Chimeric SlyD-IGF proteins allowed for the development of exceptionally specific IGF-1 and IGF-2 monoclonal antibodies. The selected antibodies bound with high affinity to the distinct IGF epitopes displayed on the protein scaffolds, as well as on the mature human IGF isoforms. The respective SlyD scaffolds display favorable engineering properties in that they are small, monomeric, and cysteine-free and can be produced in high yields in a prokaryotic host, such as Escherichia coli. In conclusion, FKBP domains from thermostable SlyD proteins are highly suitable as a generic scaffold platform for epitope grafting.

Estradiol-17β regulates the expression of insulin-like growth factors 1 and 2 via estradiol receptors in spotted scat (Scatophagus argus)

Insulin-like growth factors (Igf1 and Igf2) play a key role in growth and development of vertebrates. In mammals, the expression of IGFs is regulated by estradiol-17β (E2) via estrogen receptors (ESRs). The expression of igfs can also be regulated by E2 in fish, while comparative study of this is still lacking. The present study examined tissue distribution of igfs and hepatic expression of igfs and esrs during gonad development in Scatophagus argus by real-time PCR. Serum E2 concentration was measured by enzyme-linked immunosorbent assay (ELISA). The hepatic expression of igfs and esrs at gonadal phase III, incubated with either E2 (0.1, 1 or 10 μM) alone or in combination with estrogen receptor antagonists-fulvestrant, MPP or PHTPP, was measured. igf1 and igf2 expressed highest in liver of both sexes. Igf1, esr1 and esr2b expressions and serum E2 concentration increased, while igf2 and esr2a expressions decreased, during ovary development. Igfs and esrs expressions increased while serum E2 concentration maintained low during testis development. In females, E2 incubation enhanced the expressions of igf1 and esr1 but inhibited that of igf2 and esr2a. Both fulvestrant and MPP inhibited up-regulation effect of E2 on igf1 and esr1. Fulvestrant enhanced down-regulation effect of E2 on igf2 and esr2a, but MPP conversely. In males, E2 incubation enhanced the expressions of igfs, esr1 and esr2a. Fulvestrant and MPP inhibited up-regulation effect of E2 on igfs and esr1. PHTPP inhibited igf1 and esr2 expressions in both sexes. Our results indicated that the expression of igfs is regulated by E2 via Esrs in S. argus.

STUDY OF INSULIN-LIKE GROWTH FACTORS IN THE BLOOD OF PATIENTS WITH SQUAMOUS CELL CARCINOMA OF THE TONGUE AND LOWER ORAL MUCOSA RECEIVING THERAPY WITH MONOCLONAL ANTIBODIES - CETUXIMAB

The purpose of the study was to measure blood levels of insulin-like growth factors in patients with squamous cell carcinoma of the tongue and lower oral mucosa depending of the efficacy of cetuximab chemotherapy. The study included the data on 50 patients with squamous cell carcinoma of the tongue and lower oral mucosa T3-4N0-1M0. Patients received chemotherapy with cetuximab (n=30, main group) and without it (n=20, controls). Results were compared with the values in 20 non-cancer donors. Both groups of patients were divided into two subgroups: with stable disease and partial regression. Before treatment, blood serum levels of the two insulinlike growth factors IGF-1 and IGF-2 in patients were lower than in donors by 53.5% and 20.3%, respectively. A cycle of the standard chemotherapy in the subgroup with partial regression statistically significantly increased IGF-1 levels by 33% compared to the values before treatment, while IGF-2 was both within donor and initial values and the IGF-1/IGF- 2 ratio was similar to the initial level but 33% lower than in donors. Cetuximab chemotherapy in patients with partial regression normalized IGF-1 levels increasing it compared to initial values - by 87%. IGF-2 levels did not differ statistically significantly from their initial values and were 32.5% lower than in donors. The IGF-1/IGF-2 ratio was 58% higher than before treatment. Two therapy types demonstrated than cetuximab chemotherapy normalized IGF-1 in patients with partial tumor regression shown by the IGF-1 increase up to normal blood levels in effective treatment.

SAT-LB069 Differential Regulation of Hypothalamic and Hepatic Reproductive Signals by Leptin and Sex Steroids in the Mozambique Tilapia Oreochromis mossambicus

Reproduction is a physiologically demanding process that relies on energy sufficiency, the lack of which can result in delayed puberty and suppression of reproductive function. The pleiotropic peptide hormone leptin is a key signal in energy homeostasis that relays information on peripheral energy availability to central circuits. In mammals, leptin has been found to serve as a critical permissive signal in the activation of the gonadotropic axis and onset of puberty. Although leptin effects on reproduction have been explored extensively in mammals, its actions and regulatory properties on reproduction in fishes remain unclear. The current study assesses (i) the effect of in vivo leptin treatment on hypothalamic kisspeptin (kiss2) and gonadotropin-releasing hormone (gnrh1), (ii) the effect of leptin treatment on major egg-yolk precursors, vitellogenins (vtga, vtgb, vtgc), and insulin-like growth factor (igf1) in primary tilapia hepatocytes, and (iii) the effect of sex steroid treatment on leptin (lep) and insulin-like growth factor in primary tilapia hepatocytes. Gene expression of lep in the liver, the primary source of circulating hormone, increased with gonadosomatic index and sexual maturation of male and female tilapia, suggesting the hormone may regulate reproductive function. Intraperitoneal injection and 6-hour treatment with recombinant tilapia leptin (rtLep) in adult male tilapia resulted in increased hypothalamic kiss2 and gnrh1 transcript levels versus saline control (P < 0.01). In primary hepatocyte culture, rtLep suppressed vtgb and vtgc transcript levels (P < 0.01), while it stimulated igf1 (P < 0.0001). Testosterone and estradiol reduced lep levels (P < 0.001), but disparately regulated ­igf1 whereby testosterone increased igf1 and estradiol decreased igf1 at 10 and 100 nM (P < 0.001). The non-aromatizable 11-ketotestosterone increased lep and igf1 transcript levels at 100 nM (P < 0.05). Our findings suggest that leptin expression rises with sexual maturation and the hormone exerts stimulatory effects on hypothalamic gonadotropic factors. By contrast, leptin reduces estrogen-sensitive vitellogenesis while promoting elements of the somatotropic axis (e.g., igf1), suggesting the hormone may have dual roles in regulating reproductive and somatic growth processes. We speculate that this latter effect may be associated with limiting energy partitioning to reproduction in instances of negative energy balance. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Molecular Ontogeny of First-Feeding European Eel Larvae.

Digestive system functionality of fish larvae relies on the onset of genetically pre-programmed and extrinsically influenced digestive functions. This study explored how algal supplementation (green-water) until 14 days post hatch (dph) and the ingestion of food [enriched rotifer (Brachionus plicatilis) paste] from 15 dph onward affects molecular maturation and functionality of European eel larval ingestion and digestion mechanisms. For this, we linked larval biometrics to expression of genes relating to appetite [ghrelin (ghrl), cholecystokinin (cck)], food intake [proopiomelanocortin (pomc)], digestion [trypsin (try), triglyceride lipase (tgl), amylase (amyl)], energy metabolism [ATP synthase F0 subunit 6 (atp6), cytochrome-c-oxidase 1 (cox1)], growth [insulin-like growth factor (igf1)] and thyroid metabolism [thyroid hormone receptors (thrαA, thrβB)]. Additionally, we estimated larval nutritional status via nucleic acid analysis during transition from endogenous and throughout the exogenous feeding stage. Results showed increased expression of ghrl and cck on 12 dph, marking the beginning of the first-feeding window, but no benefit of larviculture in green-water was observed. Moreover, expression of genes relating to protein (try) and lipid (tgl) hydrolysis revealed essential digestive processes occurring from 14 to 20 dph. On 16 dph, a molecular response to initiation of exogenous feeding was observed in the expression patterns of pomc, atp6, cox1, igf1, thrαA and thrβB. Additionally, we detected increased DNA contents, which coincided with increased RNA contents and greater body area, reflecting growth in feeding compared to non-feeding larvae. Thus, the here applied nutritional regime facilitated a short-term benefit, where feeding larvae were able to sustain growth and better condition than their non-feeding conspecifics. However, RNA:DNA ratios decreased from 12 dph onward, indicating a generally low larval nutritional condition, probably leading to the point-of-no-return and subsequent irreversible mortality due to unsuccessful utilization of exogenous feeding. In conclusion, this study molecularly identified the first-feeding window in European eel and revealed that exogenous feeding success occurs concurrently with the onset of a broad array of enzymes and hormones, which are known to regulate molecular processes in feeding physiology. This knowledge constitutes essential information to develop efficient larval feeding strategies and will hopefully provide a promising step toward sustainable aquaculture of European eel.