Growth Hormone Receptor Expression Research Articles

Dietary feed nanozeolite, Pediococcus, and medium-chain fatty acid enhanced growth performance and transcription of growth-related gene of Nile tilapia (Oreochromis niloticus)

AbstractThe current trial was designed to evaluate the positive impacts of different feed additives singly or in combination on the growth performance, nutritional parameters, intestinal histology, and gene expression of some growth and fat metabolism-related genes in the liver tissue of Nile tilapia. The experimented fish were allocated into eight groups in a glass aquarium (10 fish/aquarium in triplicate) with Pediococcus acidilactici, nanozeolites, and/or medium-chain fatty acid additives. The studied treatments were control (T0), nanozeolite (T1), Pediococcus (T2), medium-chain fatty acid (T3), nanozeolite + Pediococcus (T4), nanozeolite + medium-chain fatty acid (T5), Pediococcus + medium-chain fatty acid (T6), and nanozeolite + Pediococcus + medium-chain fatty acid (T7). The results of the growth and nutritional parameters (i.e., final body weight, total weight gain, feed intake, specific growth rate, feed conversion ratio, and protein efficiency ratio) of tilapia-fed diets supplemented with Pediococcus, nanozeolites, and medium-chain fatty acids improved, but the combination of these additives was significantly more effective. Moreover, expression of growth hormone receptor 1 gene was upregulated (P ≤ 0.05) in T7 fish when compared with T0, other groups showing intermediate values. Expression of insulin-like growth factor-1 was upregulated (P ≤ 0.05) in T5, T6, and T7 fish when compared with the other groups. The expression of the fatty acid-binding protein was higher in T6 and T7 fish (P ≤ 0.05) when compared with T0, T1, and T3 fish. In conclusion, combined additives had significant effects on improving growth and regulating growth-related genes.

Acromegalic Rat Model Presented Cognitive Impairments and Tau Hyperphosphorylation in Hippocampus.

Acromegaly patients, in addition to the most prominent physical and endocrine changes, also exhibit a higher risk of cognitive dysfunction. However, the reasons and mechanisms underlying cognitive impairments in acromegaly patients remain unknown. Acromegalic rats were induced by subcutaneous injection of tumor cells, with continuous monitoring of body weight and hormonal to confirm the occurrence of acromegaly. Behavioral assessments, including Open Field Test, Novel Object Recognition Test, and Barnes maze Test, were conducted to evaluate the animals' cognitive function. Western blotting, immunohistochemistry, and immunofluorescence techniques were employed to examine changes in hippocampal tau protein, Aβ, and associated signaling pathways. The tumor cells secreting growth hormone increased the secretion of growth hormone, resulting in changes in body size and endocrine functions, thus causing acromegaly. The acromegaly model showed deficiencies in working memory and spatial memory. Hyperphosphorylation of tau protein was observed in the hippocampus of the acromegaly model, but no Aβ deposition was observed. The acromegaly model exhibits hippocampal growth hormone (GH) resistance, decreased expression of GH receptors, and subsequently reduced expression activity of the PI3K-Akt-GSK3β signaling pathway, which is responsible for the hyperphosphorylation of tau protein. The prolonged elevation of GH and insulin-like growth factor 1 (IGF-1) levels caused by acromegaly may lead to abnormalities in the SD rat's PI3K-Akt-GSK3β signaling pathway, subsequently resulting in hyperphosphorylation of hippocampal tau protein and cognitive impairment.

Tmem263 deletion disrupts the GH/IGF-1 axis and causes dwarfism and impairs skeletal acquisition

Genome-wide association studies (GWAS) have identified a large number of candidate genes believed to affect longitudinal bone growth and bone mass. One of these candidate genes, TMEM263, encodes a poorly characterized plasma membrane protein. Single nucleotide polymorphisms in TMEM263 are associated with bone mineral density in humans and mutations are associated with dwarfism in chicken and severe skeletal dysplasia in at least one human fetus. Whether this genotype-phenotype relationship is causal, however, remains unclear. Here, we determine whether and how TMEM263 is required for postnatal growth. Deletion of the Tmem263 gene in mice causes severe postnatal growth failure, proportional dwarfism, and impaired skeletal acquisition. Mice lacking Tmem263 show no differences in body weight within the first 2 weeks of postnatal life. However, by P21 there is a dramatic growth deficit due to a disrupted growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis, which is critical for longitudinal bone growth. Tmem263-null mice have low circulating IGF-1 levels and pronounced reductions in bone mass and growth plate length. The low serum IGF-1 in Tmem263-null mice is associated with reduced hepatic GH receptor (GHR) expression and GH-induced JAK2/STAT5 signaling. A deficit in GH signaling dramatically alters GH-regulated genes and feminizes the liver transcriptome of Tmem263-null male mice, with their expression profile resembling wild-type female, hypophysectomized male, and Stat5b-null male mice. Collectively, our data validates the causal role for Tmem263 in regulating postnatal growth and raises the possibility that rare mutations or variants of TMEM263 may potentially cause GH insensitivity and impair linear growth.

Tmem263 deletion disrupts the GH/IGF-1 axis and causes dwarfism and impairs skeletal acquisition.

Genome-wide association studies (GWAS) have identified a large number of candidate genes believed to affect longitudinal bone growth and bone mass. One of these candidate genes, TMEM263, encodes a poorly characterized plasma membrane protein. Single nucleotide polymorphisms in TMEM263 are associated with bone mineral density in humans and mutations are associated with dwarfism in chicken and severe skeletal dysplasia in at least one human fetus. Whether this genotype-phenotype relationship is causal, however, remains unclear. Here, we determine whether and how TMEM263 is required for postnatal growth. Deletion of the Tmem263 gene in mice causes severe postnatal growth failure, proportional dwarfism, and impaired skeletal acquisition. Mice lacking Tmem263 show no differences in body weight within the first 2 weeks of postnatal life. However, by P21 there is a dramatic growth deficit due to a disrupted growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis, which is critical for longitudinal bone growth. Tmem263-null mice have low circulating IGF-1 levels and pronounced reductions in bone mass and growth plate length. The low serum IGF-1 in Tmem263-null mice is associated with reduced hepatic GH receptor (GHR) expression and GH-induced JAK2/STAT5 signaling. A deficit in GH signaling dramatically alters GH-regulated genes and feminizes the liver transcriptome of Tmem263-null male mice, with their expression profile resembling wild-type female, hypophysectomized male, and Stat5b-null male mice. Collectively, our data validates the causal role for Tmem263 in regulating postnatal growth and raises the possibility that rare mutations or variants of TMEM263 may potentially cause GH insensitivity and impair linear growth.

The Effect of Metformin Treatment on Disease Control in Patients with Acromegaly.

The increase in portal insulin levels has been shown to upregulate growth hormone receptor expression in the liver, leading to increased insulin-like growth hormone- 1 levels. Metformin inhibits hepatic gluconeogenesis and reduces fasting insulin. We evaluated the effect of metformin treatment in patients with acromegaly on growth hormone, insulin-like growth hormone-1, and pituitary adenoma size. Patients who were followed up with the diagnosis of acromegaly in Istanbul University- Cerrahpaşa, Cerrahpaşa Medical Faculty were evaluated. The patients were divided into three groups after pituitary adenectomy as those who received somatostatin receptor ligand and metformin treatment (group A), somatostatin receptor ligand treatment only (group B), and those who received metformin treatment only (group C). Groups A and B were compared with each other, and patients in group C were compared among themselves. While the median insulin-like growth factor-1 level decreased to 170 ng/ml in Group A after the treatment, the median insulin-like growth factor-1 level decreased to 229 ng/ml in Group B, and a statistically significant difference was found between the two groups (p =0.020). There was no significant difference in post-treatment growth hormone levels and residual adenoma sizes between groups A and B (p >0.005). In group C, there was no significant difference in growth hormone values pre-and post-metformin treatment (p =0.078); however, the median insulin-like growth factor-1 level decreased from 205 ng/ml to 168 ng/ml during metformin treatment and was found to be statistically significant (p =0.027). Due to the effect of metformin treatment on insulin-like growth factor-1 values in patients with acromegaly, it can be used in disease control, as well as diabetes treatment.

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.

Insights into the interaction between stocking density and feeding rate in fish Megalobrama ambylcephala based on growth performance, innate immunity, antioxidant activity, and the GH-IGF1 axis

The interaction between stocking density and feeding rate was investigated in juvenile blunt snout bream (Megalobrama ambylcephala) (11.94 ± 0.04 g) based on growth performance and health status. A 2 × 4 factorial design was adopted, containing two stocking densities (10 and 20 fish/m3) and four feeding rates (3%, 4%, 5% and 6% body weight/day). After the 12-weeks feeding trial, high stocking density (20 fish/m3) significantly (P < 0.05) reduced weight gain rate (WGR), feed intake (FI), protein efficiency ratio (PER), nitrogen and energy retention efficiency (NRE and ERE), plasma immunoglobulin M (IgM) level, plasma lysozyme (LZM), myeloperoxidase (MPO) and alkaline phosphatase (AKP) activities, as well as hepatic superoxide dismutase (SOD) and catalase (CAT) activities, while the opposite was observed in feed conversion rate (FCR), condition factor (CF) and plasma complement 4 (C4) level. The highest feeding rate (6%) significantly (P < 0.05) increased WGR, FI, FCR, CF, the intraperitoneal fat ratio and the protein expression of growth hormone receptor, but significantly (P < 0.001) decreased PER, NRE and ERE. Moderate feeding rates (4%–5%) significantly (P < 0.05) increased body lipid and energy contents, the activities of SOD, CAT, glutathione peroxidase, LZM, MPO, AKP and acid phosphatase, the levels of complement 3 and 4 (C3 and C4), and the transcriptions and protein levels of growth hormone and insulin-like growth factor 1, while the opposite was noted in the malondialdehyde content. Furthermore, an interactive effect between stocking density and feeding rate was also noted in WGR, FI, plasma ACP, AKP and MPO activities, and liver malondialdehyde content. In summary, stocking density and feeding rate interactively affect the growth performance and health status of blunt snout bream. The optimum feeding rate of this species increased when cultured under high-density conditions.

Growth Axis Somatostatin, Growth Hormone Receptor, and Insulin-like Growth Factor-1 Genes Express and Are Affected by the Injection of Exogenous Growth Hormone in Chinemys reevesii.

In this study, to explore the effect of growth hormone changes on the related genes and regulatory roles of the turtle, PCR amplification, real-time fluorescence quantitative analysis, and enzyme cutting technology were used to clone and sequence the somatostatin (SS) gene, growth hormone receptor (GHR), and insulin-like growth factor-1 (IGF-I) sequence of Chinemys reevesii. The effects of human growth hormone on the mRNA expression of growth-axis-related genes SS, GHR, and IGF-1 in different sexes were observed. The study of the SS gene in turtles using real-time fluorescence quantitative PCR showed that the SS gene was mainly expressed in the nervous system and the digestive system, with the highest expression found in the brain, while the GHR gene and the IGF-I gene were expressed in all tissues of Chinemys reevesii. The SS gene was expressed in the brain, pituitary, liver, stomach, and intestine, with the highest expression in the brain and the lowest expression in the liver. Within 4 weeks of the injection of exogenous growth hormone, the expression level of the SS gene in the brain of both sexes first increased and then decreased, showing a parabolic trend, and the expression level of the experimental group was lower than that of the control group. After the injection of growth hormone (GH), the expression of the GHR gene in the liver of both sexes showed a significant increase in the first week, decreasing to the control group level in the second week, and then gradually increasing. Finally, a significant level of difference in the expression of the GHR gene was reached at 3 and 4 weeks. In terms of the IGF-I gene, the changing trend of the expression level in the liver was the same as that of the GHR gene. After the injection of exogenous growth hormone, although the expression of the SS gene increased the inhibition of the secretion of the GHR gene by the Reeves' turtle, exogenous growth hormone could replace the synthesis of GH and GHR, accelerating the growth of the turtle. The experiments showed that the injection of recombinant human growth hormone affects the expression of SS, GHR, and IGF-1 genes, and promotes the growth of the Reeves' turtle.

An investigation of the assumed efficacy of methionine hydroxy analogue compared to DL-methionine by measuring growth performance, carcass traits, and GHR and IGF-I expression in broilers

This experiment was conducted to investigate the assumed efficacy of 65% on the product basis of methionine hydroxy analog (OH-Met, 88% aqueous solution of DL-2-hydroxy-4-(methylthio) butanoic acid) relative to DL-methionine (DL-Met) in broiler chickens. A total of 792-day-old male chickens were randomly allotted to 7 dietary treatments consisting of a methionine deficient-basal diet based on corn-soybean meal and 6 different diets obtained by supplying the basal diet with methionine at 3 levels (25, 100 and 125%; levels of addition relative to the required amount of additional Met to meet SID Met + Cys requirements) from either DL-Met or OH-Met at a ratio of 65:100 (DL-Met to OH-Met on a product basis) in the corresponding treatments. Regardless of the source, methionine supplementation enhanced (p < .05) growth performance, carcase and breast meat yield. Supplemental level and the source of Met had no significant effect on the proximate chemical composition of breast meat (p > .05). Comparison of effects of OH-Met and DL-Met supplemented at 100–65% weight ratio revealed no differences at any Met + Cys level and for performance criterion confirming the applied concept. Expression of growth hormone receptor (GHR) mRNA, which showed a positive correlation with body weight gain, carcase yield and breast percentage, in broiler liver significantly increased with 100% and 125% relative addition of DL-Met, while only 100% of OH-Met addition did (p < .05) when compared to the basal diet. The expression of the insulin-like growth factor-I (IGF-I) gene was not significantly affected by either Met source or supplementation level. In conclusion, our data indicated that DL-Met can be substituted with a 1.54 times higher amount of OH-Met in corn-soybean meal based broiler diets.

A cluster of X-linked miRNAs are de-repressed with age in mouse liver and target growth hormone signaling.

Growth hormone (GH) signaling influences lifespan in a wide variety of mammalian species. We previously reported that a cluster of miRNAs located on the X-chromosome are de-repressed with age in male mouse liver, and a subset, the mir-465 family, can directly attenuate expression of the growth hormone receptor (GHR) in vitro leading to a reduction in GH signaling. Here we show that this cluster of miRNAs is also upregulated in the liver with age in females, and that calorie restriction and the Ames dwarf genotype, both known to delay aging, attenuate the upregulation of the miRNA cluster. Upregulation of mir-465 in vivo leads to a reduction in GHR mRNA in the liver and an attenuation of GH signaling, indicated by a reduction in GHR, IGF-1, IGFBP3, and ALS mRNA expression. There is a corresponding reduction in IGF-1 protein levels in the liver and plasma. These results suggest that the age-associated upregulation of the X-chromosomal cluster of miRNAs could influence lifespan.

THU545 Growth Hormone Receptor Antagonist As A Novel Combination Therapy Against Triple Negative Breast Cancer

Abstract Disclosure: P. Mora-Criollo: None. R. Basu: None. J.J. Kopchick: None. Triple Negative breast (TNBC) cancer is classified based on the absence of ER-, PR-, and HER2- receptors and is associated with high metastatic potential. TNBC accounts for approximately 15-20% of new breast cancer diagnoses and is responsible for most breast cancer-related deaths. First-line treatment of anticancer drugs can be effective in 30-70% of patients with TNBC, but during treatment, more than half of the patients develop resistance and progress into metastatic disease. Previous studies have demonstrated the link between growth hormone receptor (GHR) expression and mammary carcinogenesis and established that GHR signaling promotes breast cancer development and progression. Conversely, inhibition of GHR expression has been shown to arrest tumor initiation and reduce metastasis of mammary carcinoma cells. Here we present the feasibility studies for employing GHR as a target for novel combination therapeutic approaches in TNBC. We performed retrospective analysis of GHR transcript expression and survival in TNBC patients, followed by experimental data in cellular models using combinations of Pegvisomant (an FDA-approved GHR antagonist) with chemotherapeutic agents, as a potential therapeutic option in TNBC. Survival probability plots from the TCGA dataset of 405 TNBC samples showed that patients expressing high levels of the GHR showed a significantly poor survival (27 months, p=0.038) compared to patients expressing low GHRs (40.37 months). Additionally, human breast cancer MDA-MB-453 cells, when treated with human (hGH)(2.5 nM) increased activation of JAK2, STAT5, SRC, ERK1/2, and AKT, associated with cancer progression. Importantly, treatment of the cells with Paclitaxel (1 nM) + (hGH)(2.5 nM) increased ABCG2 expression and the epithelial-to-mesenchymal transition (EMT) makers (SLUG, SNAIL, N-cad) associated with drug resistance and tumor progression. On the contrary, when cells were treated with Pegvisomant (500 nM) in combination with Paclitaxel + GH, a significant decrease in protein and RNA expression of ABCG2 as well as EMT markers was observed. Next, serum collected from GH antagonist (GHA) mice and WT as control, were used to treat PY8119 mouse cells in combination with Paclitaxel (1 nM) + bovine (bGH)(2.5 nM). Downregulation of protein and RNA expression levels of ABCG2 as well EMT makers in GHA serum treatment compared to WT was also found. This preliminary data shows that the GHR antagonist, Pegvisomant, in combination with anticancer drugs, can be effective in attacking drug resistance in TNBC. Key words: Pegvisomant, growth hormone receptor Presentation: Thursday, June 15, 2023

OR01-05 Growth Hormone Action In Somatostatin Neurons Regulates Anxiety And Fear Memory

Abstract Disclosure: W.O. dos Santos: None. V.A. Juliano: None. H.R. Vieira: None. R. Frazao: None. C.D. Munhoz: None. J. Donato: None. Dysfunctions in growth hormone (GH) secretion increase the prevalence of anxiety and depression. Furthermore, GH receptor (GHR) signaling in the amygdala has been associated with fear memory, a key feature of post-traumatic stress disorder. However, it is currently unknown which neuronal population is targeted by GH action to influence neuropsychiatric diseases. Here we showed that approximately 60% of somatostatin (SST)-expressing neurons in the extended amygdala are directly responsive to GH. GHR ablation in SST-expressing cells (SSTΔGHR mice) led to increased anxiety in the light-dark box and elevated plus maze tests, whereas SSTΔGHR females showed no changes in anxiety, compared to control animals. Using auditory Pavlovian fear conditioning, both male and female SSTΔGHR mice exhibited a significant reduction in fear memory. In contrast, GHR ablation in SST neurons did not affect memory in the novel object recognition test. The gene expression was analyzed in a bilateral micropunch comprising the central nucleus of the amygdala and basolateral complex of male mice. Increased mRNA expression of Gabbr2 (GABAB2 receptor), Syp (synaptophysin), and Bdnf were observed in the amygdala of SSTΔGHR mice. In conclusion, GHR expression in SST neurons is necessary to regulate anxiety in males, but not in female mice. GHR ablation in SST neurons also decreases fear memory and affects the gene expression in the amygdala. Our findings identified for the first time a specific neuronal population responsible for mediating the effects of GH on behavioral aspects associated with neuropsychiatric diseases. Presentation: Thursday, June 15, 2023

SAT605 Growth Hormone Action In Somatostatin Neurons Regulates Anxiety And Fear Memory

Abstract Disclosure: W.O. dos Santos: None. V.A. Juliano: None. H.R. Vieira: None. R. Frazao: None. C.D. Munhoz: None. J. Donato: None. Dysfunctions in growth hormone (GH) secretion increase the prevalence of anxiety and depression. Furthermore, GH receptor (GHR) signaling in the amygdala has been associated with fear memory, a key feature of post-traumatic stress disorder. However, it is currently unknown which neuronal population is targeted by GH action to influence neuropsychiatric diseases. Here we showed that approximately 60% of somatostatin (SST)-expressing neurons in the extended amygdala are directly responsive to GH. GHR ablation in SST-expressing cells (SSTΔGHR mice) led to increased anxiety in the light-dark box and elevated plus maze tests, whereas SSTΔGHR females showed no changes in anxiety, compared to control animals. Using auditory Pavlovian fear conditioning, both male and female SSTΔGHR mice exhibited a significant reduction in fear memory. In contrast, GHR ablation in SST neurons did not affect memory in the novel object recognition test. The gene expression was analyzed in a bilateral micropunch comprising the central nucleus of the amygdala and basolateral complex of male mice. Increased mRNA expression of Gabbr2 (GABAB2 receptor), Syp (synaptophysin), and Bdnf were observed in the amygdala of SSTΔGHR mice. In conclusion, GHR expression in SST neurons is necessary to regulate anxiety in males, but not in female mice. GHR ablation in SST neurons also decreases fear memory and affects the gene expression in the amygdala. Our findings identified for the first time a specific neuronal population responsible for mediating the effects of GH on behavioral aspects associated with neuropsychiatric diseases. Presentation: Saturday, June 17, 2023

OR05-04 Growth Hormone Receptor Antagonism Markedly Improves Therapeutic Response In Mouse Models Of Melanoma, Liver Cancer, Pancreatic Cancer And Cholangiocarcinoma

Abstract Disclosure: R. Basu: None. P. Kulkarni: None. S. Duran Ortiz: None. E. Davis: None. J.J. Kopchick: None. A major hurdle in tackling cancer, the second biggest cause of human mortality, is resistance to therapy. Human growth hormone (GH) mediated activation of the growth hormone receptor (GHR) promotes the initiation and invasive progression of several types of human cancers, known since 1950. Recently, through a series of mechanistic studies using in vitro models and in silico analyses of human cancer patient databases, we have identified a covert role of GH in promoting cancer drug resistance via direct upregulation of: (i) the expression of ATP-binding cassette containing multi-drug transporters (ABC transporters) leading to increased drug efflux, (ii) the epithelial-to-mesenchymal transition (EMT) associated gene expression program, and (iii) the mediators of fibrosis and extracellular matrix remodeling. Additionally, based on the known effects of GH and robust expression of GHR in multiple cell types that constitute the tumor microenvironment, autocrine / paracrine GH putatively exerts potent tumor supportive actions. Therefore, we hypothesized that combining GHR antagonist to chemotherapy can markedly improve therapeutic outcome in human cancers. Melanoma and liver cancer jointly and annually constitute &amp;gt;150,000 patients and &amp;gt;60,000 deaths in the US, much due to resistance to therapy. We used a syngeneic murine model of both cancers using C57BL6 mice transgenic for a GHR antagonist (GHA mice) compared against wild-type (WT) counterparts implanted with either B16F10 melanoma or Hepa-1-6 hepatoma cells. GHA expression drastically sensitized melanoma tumors to cisplatin treatment and hepatoma tumors to sorafenib treatment. Additionally, the five-year survival rates of pancreatic cancer and cholangiocarcinoma are a dismal 10% in 2022, indicating an urgent need for new therapeutic approaches for both of these devastating diseases. For this, we used Nude mice for human pancreatic cancer xenografts treated +/- GHA (Pegvisomant and another in development at our laboratory) combined with gemcitabine. Combination of GHA markedly sensitized pancreatic cancer xenografts to gemcitabine in Nude mice, leading to ∼40% of mice being tumor-free at the end of study. GHA similarly also sensitized human cholangiocarcinoma xenografts in Nude mice to gemcitabine-cisplatin therapy. In all cases, GHA led to a marked reduction in gene expression of multidrug efflux transporters, EMT markers, and fibrosis mediators. Collectively, our data provides strong pre-clinical validation for treatment regimens combining GHR antagonist and chemotherapy leading to highly efficacious tumor clearance. Presentation: Thursday, June 15, 2023

Hydrogen administration improves the growth performance of juvenile largemouth bass (Micropterus salmoides) by increasing feed intake, reducing serum lipids, activating mTOR and Nrf2 signaling pathways, and altering the intestinal microbiota

Hydrogen (H2) gas is recognized for its anti-oxidative, anti-apoptotic, and anti-inflammatory properties in multiple plant and animal models. Nevertheless, there is a lack of research on the effects of H2 administration on fish. This research seeks to investigate how H2 administration affects the growth performance, mammalian target of rapamycin (mTOR) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways, and intestinal microbiota of juvenile largemouth bass under normal feeding conditions. The research randomly allocated 240 fish (3.55 ± 0.01 g) into two treatment groups, each comprising 4 replicate tanks with 30 fish per tank. The control group was maintained in regular water, while the experimental group (referred to as H2 group) was treated with H2-dissolved water for 1 h per day for 6 weeks. Upon analysis of both groups, it was revealed that the weight gain, final weight, feed intake, specific growth rate, and survival rate were significantly improved by H2 treatment (P < 0.05). In addition, administration of H2 significantly reduced the triglyceride content and increased the high-density lipoprotein-cholesterol content in the serum (P < 0.05). Moreover, administration of H2 led to a significant increase in the expression of genes associated with mTOR (PI3K, AKT, TOR, S6K1, and 4EBP1) and Nrf2 (Nrf2, SOD, and GPX) signaling pathways (P < 0.05). Furthermore, H2 significantly increased the expression of growth hormone receptor (GHR) and neuropeptide Y (NPY) genes in the brain of juvenile largemouth bass. H2 did not significantly affect intestinal histology. However, it significantly increased the relative abundance of Sulfuritalea, Bradyrhizobium, and norank_f__Beggiatoaceae (P < 0.05) and reduced the relative abundance of Brevundimonas, unclassified_o__Chlamydiales, and Delftia in the intestinal microbiota (P < 0.05). Thus, these results suggested that providing juvenile largemouth bass with H2-dissolved water for 1 h per day can lead to a significantly increasing in growth performance, stimulating feed intake, activating mTOR and Nrf2 signaling pathways, and augmenting the abundance of beneficial bacteria in the intestines of juvenile largemouth bass. These findings provided a valuable support for the H2 application in the largemouth bass healthy culture.

Growth Hormone Action in Somatostatin Neurons Regulates Anxiety and Fear Memory.

Dysfunctions in growth hormone (GH) secretion increase the prevalence of anxiety and other neuropsychiatric diseases. GH receptor (GHR) signaling in the amygdala has been associated with fear memory, a key feature of posttraumatic stress disorder. However, it is currently unknown which neuronal population is targeted by GH action to influence the development of neuropsychiatric diseases. Here, we showed that approximately 60% of somatostatin (SST)-expressing neurons in the extended amygdala are directly responsive to GH. GHR ablation in SST-expressing cells (SSTΔGHR mice) caused no alterations in energy or glucose metabolism. Notably, SSTΔGHR male mice exhibited increased anxiety-like behavior in the light-dark box and elevated plus maze tests, whereas SSTΔGHR females showed no changes in anxiety. Using auditory Pavlovian fear conditioning, both male and female SSTΔGHR mice exhibited a significant reduction in fear memory. Conversely, GHR ablation in SST neurons did not affect memory in the novel object recognition test. Gene expression was analyzed in a micro punch comprising the central nucleus of the amygdala (CEA) and basolateral (BLA) complex. GHR ablation in SST neurons caused sex-dependent changes in the expression of factors involved in synaptic plasticity and function. In conclusion, GHR expression in SST neurons is necessary to regulate anxiety in males, but not female mice. GHR ablation in SST neurons also decreases fear memory and affects gene expression in the amygdala, although marked sex differences were observed. Our findings identified for the first time a neurochemically-defined neuronal population responsible for mediating the effects of GH on behavioral aspects associated with neuropsychiatric diseases.SIGNIFICANCE STATEMENT Hormone action in the brain regulates different neurological aspects, affecting the predisposition to neuropsychiatric disorders, like depression, anxiety, and posttraumatic stress disorder. Growth hormone (GH) receptor is widely expressed in the brain, but the exact function of neuronal GH action is not fully understood. Here, we showed that mice lacking the GH receptor in a group of neurons that express the neuropeptide somatostatin exhibit increased anxiety. However, this effect is only observed in male mice. In contrast, the absence of the GH receptor in somatostatin-expressing neurons decreases fear memory, a key feature of posttraumatic stress disorder, in males and females. Thus, our study identified a specific group of neurons in which GH acts to affect the predisposition to neuropsychiatric diseases.

O-206 Growth hormone supplementation reduces aneuploidy and improves the quality of aged oocytes by activating the JAK2-ERK1/2 pathway

Abstract Study question Does growth hormone (GH) supplementation improves the quality of oocytes in aged mice via reducing aneuploidy? Summary answer Daily injections of GH for 8 weeks reduces aneuploidy by activating JAK2-ERK1/2 pathway and improves the quality of oocyte in aged mice. What is known already Aging-induced low-quality oocytes, which are mainly caused by aneuploidy, decrease female fertility. However, few treatments are available to improve the poor quality of oocytes in aged women. Age-related decline in GH levels may be related to the insufficient reproductive potential in aged women. Several studies have reported that GH improves assisted reproductive technology outcomes in poor ovarian response patients, although its role is still controversial. In animal models, GH supplementation improved the oocyte quality by enhancing mitochondrial function. However, whether GH reduces the aneuploidy rate in aged oocytes, and if so the underlying mechanisms, are unclear. Study design, size, duration The aged (8-month-old) C57BL/6J female mice were used in the study. For the in vivo experiments, the aged mice were intraperitoneally injected with GH (GenSci, Changchun, China; 1.6 mg/kg body weight) or an equivalent volume of normal saline for 8 weeks; For the in vitro experiments, germinal vesicle (GV) oocytes from aged mice were treated with GH (200 ng/mL) or PBS in M16 medium. Participants/materials, setting, methods We counted oocytes by immunohistochemistry to assess ovarian reserve. The expression of growth hormone receptor and mitochondrial genes were measured by quantitative real-time PCR. Time–lapse incubator was utilized to record the developmental potential of early embryos. Immunofluorescence was performed to assess parameters of oocyte quality (mitochondrial functions, spindle/chromosome defects, and DNA damage). Chromosome spread and DNA sequencing were used to analyze aneuploidy rate. We performed quantitative proteomics analysis to identify the potential targets of GH. Main results and the role of chance Firstly, we found that GH promoted GHR expression in aged oocytes (30.64±1.70 vs 21.68±1.08, P &amp;lt; 0.001). GH ameliorated aging-induced decline in ovarian reserve of aged mice, with increased ovarian index (0.040%±0.0031 vs 0.023%±0.0019, P &amp;lt; 0.01), and number of antral follicles (8.67±1.2 vs 3.33±0.88, P &amp;lt; 0.05) compared to the controls. In addition, GH improved the quality of aged oocytes, representing restored mitochondrial functions (P &amp;lt; 0.05), decreased DNA damage (23.37±1.76 vs 38.35±2.52, P &amp;lt; 0.001) . As expected, GH promoted the fertilization rate (39.9%±1.10 vs 14.4%±0.62, P &amp;lt; 0.001) and early embryo development (P &amp;lt; 0.01) of aged oocytes. Of note, GH recovered the spindle/chromosome defects (42.6%±2.12 vs 63.9%±1.83, P &amp;lt; 0.01, and reduced aneuploidy rate (20.9%±1.61 vs 39.3%±1.84, P &amp;lt; 0.01) in aged oocytes. GH activated ERK1/2 expression to decrease aneuploidy rate in aged oocytes. In addition, JAK2 might be involved in the regulation of GH on ERK1/2 expression in aged oocytes. Altogether, GH restored age-related decline in oocyte number, and decreased the occurrence rate of aneuploidy by activating JAK2-ERK1/2 pathway, thereby improving the quality of aged oocytes. Limitations, reasons for caution The molecular action mechanism of GH to regulate aneuploidy remains to be determined. Besides, future work should be extended to human oocyte to determine whether this mechanism is conserved between mice and humans Wider implications of the findings Our work expounds a theoretical basis for application of GH to improve the fertility of aged women. Besides, the results also feed new ideas for the prevention and treatment of oocyte quality decline in assisted reproductive technology. Trial registration number not applicable

Caloric restriction as a possible pitfall for persistent acromegaly follow-up – case report

BackgroundAcromegaly diagnosis is established when plasma levels of IGF-1 are increased and the Oral Glucose Tolerance Test (OGTT) with 75gr of glucose can’t suppress Growth Hormone (GH) levels. These two parameters are also useful during follow-up, after surgical/radiologic therapy and/or during medical therapy.Case presentationA 29-year-old woman was diagnosed with acromegaly after a severe headache. Previous amenorrhea and facial and acral changes were noticed. A pituitary macroadenoma was found, biochemical evaluation was in agreement with the suspected acromegaly and a transsphenoidal adenectomy was performed. As the disease recurred, a surgical reintervention and radiosurgery (Gamma Knife, 22 Gy) were necessary. No normalization of IGF-1 was achieved during three years after radiosurgery. Surprisingly, then, and although clinical features seemed getting worse, IGF-1 levels became consistently controlled to 0.3–0.8 times the upper limit of the reference range. Questioned, the patient referred that she was following an intermittent fasting dietary plan. However, based on the dietary questionnaire, she was found to be under severe caloric restriction. First OGTT (under caloric restriction) showed absence of GH suppression and an IGF-1 value of 234 ng/dL (Reference Range 76–286 ng/mL). A second OGTT, one month after an eucaloric diet was instituted, showed an increased IGF-1 of 294 ng/dL, maintaining an unsuppressed, yet less elevated, GH.ConclusionsGHRH/GH/IGF-1 axis controls somatic growth. Regulation is complex, and nutrition status and feeding pattern have a recognized role. Like systemic inflammation or chronic liver disease, fasting and malnutrition decrease the expression of hepatic GH receptors, with consequent reduction of IGF-1 levels, through resistance to GH. This clinical report shows that caloric restriction may represent a pitfall in acromegaly follow-up.

Characterization of dominant-negative growth hormone receptor variants reveals a potential therapeutic target for short stature.

Growth hormone insensitivity (GHI) encompasses growth restriction, normal/elevated growth hormone (GH), and low insulin-like growth factor I (IGF1). "Nonclassical" GHI is poorly characterized and is rarely caused by heterozygous dominant-negative (DN) variants located in the intracellular or transmembrane domains of the GH receptor (GHR). We sought to determine the molecular mechanisms underpinning the growth restriction in 2 GHI cases. A custom-made genetic investigative pipeline was exploited to identify the genetic cause of growth restriction in patients with GHI. Nanoluc binary technology (NanoBiT), in vitro splicing assays, western blotting, and flow cytometry, characterized the novel GHR variants. Novel heterozygous GHR variants were identified in 2 unrelated patients with GHI. In vitro splicing assays indicated both variants activated the same alternative splice acceptor site resulting in aberrant splicing and exclusion of 26 base pairs of GHR exon 9. The GHR variants produced truncated receptors and impaired GH-induced GHR signaling. NanoBiT complementation and flow cytometry showed increased cell surface expression of variant GHR homo/heterodimers compared to wild-type (WT) homodimers and increased recombinant human GH binding to variant GHR homo/heterodimers and GH binding protein (GHBP) cleaved from the variant GHRs. The findings demonstrated increased variant GHR dimers and GHBP with resultant GH sequestration. We identified and characterized 2 novel, naturally occurring truncated GHR gene variants. Intriguingly, these DN GHR variants act via the same cryptic splice acceptor site, highlighting impairing GH binding to excess GHBP as a potential therapeutic approach.

The Optimum Dietary Phenylalanine Requirement of Hybrid Grouper (Epinephelusfuscoguttatus ♀ × Epinepheluslanceolatus ♂) Juveniles: Effects on Growth Performance, Gut Micromorphology, and Antioxidation.

The optimum phenylalanine (Phe) requirement for hybrid grouper (Epinephelusfuscoguttatus ♀ × Epinepheluslanceolatus ♂) juveniles was determined through an 8-week growth trial. A total of seven isoenergetic (340 kcal per 100 g of dry matter), isonitrogenous, and isolipidic diets were made, containing 8.2 (Phe 8.2), 9.2 (Phe 9.2), 10.1 (Phe 10.1), 11.2 (Phe 11.2), 13.3 (Phe 13.3), 15.2 (Phe 15.2), and 17.3 g/kg (Phe 17.3), respectively. Triplicate tanks of juvenile fish (about 16.7 g/fish) were fed each experimental diet twice daily until apparent satiation. The results indicated that different dietary Phe levels significantly influenced weight gain percentage (WG), feed efficiency (FE), protein efficiency ratio (PER), as well as, productive protein value (PPV). Fish fed Phe 8.2 had the lowest WG or PPV among all experimental treatments. Furthermore, the optimal dietary Phe level increased fold height, width, enterocyte, and microvillus height of fish. The Phe 10.1 group exhibited higher growth hormone (GH) expression in the pituitary compared to other groups. Expression of hepatic insulin-like growth factor-1 (IGF-1) and growth hormone receptor 1 (GHR1) displayed a similar pattern of variation to that of GH. The Phe 13.3 group had lower expression of S6 kinase 1 (S6K1) and target of rapamycin (TOR) than other groups. In addition, fish fed Phe 10.1 had lower levels of nuclear factor erythroid 2 (Nrf2) and heat shock protein 70 (HSP70) in the head kidney, and Cu/Zn-superoxide (Cu/ZnSOD) dismutases in the midgut compared to fish fed other Phe levels. Generally, optimal Phe content in the diet of hybrid grouper was estimated to be 12.7 g/kg of dry matter (27.3 g/kg of dietary protein), and at this level, the feed utilization, gut micromorphology, and immunity of fish were also elevated.