Human Growth Hormone Secretion Research Articles

The revelance of the development of new reciples of protein-vitaminized products for sports nutrition in Kazakhstan (in Kazakh language)

The specificity of sports nutrition lies in the fact that a person uses various carbohydrate, protein and vegetable drinks to restore the body after physical activity. Currently, in the sports nutrition market of the CIS countries, including our country, products from other countries account for more than 95%. Because of this, the prices of sports products are very expensive. Therefore, the development of sports nutrition products containing highly digestible protein products for the body based on plant raw materials is very relevant. At the same time, the development of these products based on legumes, in particular, their peas and soybeans, is the most acceptable. In addition, pea protein can be used to build muscle mass - due to the high level of L-arginine contained in it, the protein stimulates the secretion of human growth hormone, which is involved in the regulation of growth, metabolism and muscle mass. This article presents materials on the relevance of the development of new formulations of protein - fortified products for sports nutrition in Kazakhstan.

The Role of Physical Activity in the Molecular Impact of Increased Insulin-Like Growth Factor-1 (IGF-1) Levels: A Literature Review

Insulin-like growth factor-1 (IGF-1) is a key mediator of human growth hormone (HGH), which plays an important role in promoting cell growth and differentiation in childhood and continues to exert anabolic effects in adults. IGF-1 is a small peptide that circulates in serum bound to a high affinity binding protein. IGF-1 is part of a vast network of growth factors, receptors, and binding proteins involved in mediating cell proliferation, differentiation, and apoptosis IGF-I-like growth factor has broad anabolic and insulin-sensitising effects, which are generated through endocrine (in circulation) as well as paracrine/autocrine mechanisms. Serum concentrations of IGF-1 steadily increase during childhood and peak at puberty, and continue to decline since then, as does the secretion of human growth hormone. This study aims to determine the role of physical activity in molecular impact on increasing IGF-1 levels. This article is the result of a review of various research references related to the role of physical activity in molecular impact on increasing IGF-1 levels. Physical Activity in Molecular has an impact on increasing IGF-1 levels.

Oral SSTR5 Antagonist SCO-240 for Growth Hormone Stimulation: A Phase I Single-Dose Study in Healthy Individuals.

Somatostatin inhibits endocrine and exocrine secretion in various tissues by acting on five somatostatin receptor subtypes (SSTR1-5). The clinical effects of SSTR5 antagonism remain unknown. Herein, we evaluated the effects of SCO-240, an oral SSTR5 antagonist, in healthy individuals. This randomized, single-center, double-blind, placebo-controlled, phase I study included healthy Japanese and White individuals. The effects of ascending single oral doses of SCO-240 were evaluated in healthy individuals. The main outcome measures were safety, tolerability, pharmacokinetics, and pharmacodynamics (gallbladder contractions and levels of serum insulin and plasma glucagon-like peptide-1 (GLP-1)). The levels of pituitary hormones were evaluated in our exploratory analysis. The results indicated that SCO-240 was safe and well-tolerated at all tested doses. Oral SCO-240 was readily absorbed, with its systemic exposure increasing in a dose-dependent manner. The median time to maximum concentration and mean terminal half-life of SCO-240 were 3-4 and 10.2-12.6 hours, respectively, in the ascending dose section. No clinically meaningful changes in SCO-240 pharmacokinetic profiles were observed between fed and fasted or between Japanese and White individuals. No increase in gallbladder contractions or levels of insulin and GLP-1 were detected. SCO-240 induced robust growth hormone (GH) secretion without altering the levels of other pituitary hormones. In conclusion, the study is the first to demonstrate that SSTR5 antagonism stimulates GH secretion in humans. SCO-240 was safe and well-tolerated and exhibited once-daily oral dosing potential. The robust effects of SCO-240 on GH secretion suggest that it may be a treatment option for GH-related disorders.

Sustained secretion of human growth hormone from TheraCyte devices encapsulated with PiggyBac-engineered retinal pigment epithelium cells

Growth hormone (GH) deficiency is characterized by impaired growth and development, and is currently treated by repeated administration of recombinant human GH (hGH). Encapsulated cell therapy (ECT) may offer a less demanding treatment-strategy for long-term production and release of GH into circulation. We used PiggyBac-based (PB) transposon delivery for engineering retinal pigment epithelial cells (ARPE-19), and tested a series of viral and non-viral promoters as well as codon-optimization to enhance transgene expression. Engineered cells were loaded into TheraCyte macrocapsules and secretion was followed in vitro and in vivo. The cytomegalovirus (CMV) promoter supports strong and persistent transgene expression, and we achieved clonal cell lines secreting over 6 µg hGH/106 cells/day. Codon-optimization of the hGH gene did not improve secretion. ARPE-19 cells endured encapsulation in TheraCyte devices, and resulted in steady hormone release for at least 60 days in vitro. A short-term pilot experiment in immunodeficient SCID mice demonstrated low systemic levels of hGH from a single 40 µL capsule implanted subcutaneously. No significant increase in weight increase or systemic hGH was detected after 23 days in the GH-deficient lit/SCID mouse model using 4.5 µL capsules loaded with the highest secreting clone of ARPE-19 cells. Our results demonstrate that PB-mediated engineering of ARPE-19 is an efficient way to generate hormone secreting cell lines compatible with macroencapsulation, and our CMV-driven expression cassette allows for identification of clones with high level and long-term secretory activity without addition of insulator elements. Our results pave the way for further in vivo studies of encapsulated cell therapy.

RNA profiling of human growth hormone-secreting and non-functioning pituitary adenomas reveals novel and differentially expressed immune related genes

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Optimization of expression, purification and secretion of functional recombinant human growth hormone in Escherichia coli using modified staphylococcal protein a signal peptide

BackgroundHuman Growth Hormone (hGH) is a glycoprotein released from the pituitary gland. Due to the wide range of effects in humans, any disruption in hGH secretion could have serious consequences. This highlights the clinical importance of hGH production in the treatment of different diseases associated with a deficiency of this hormone. The production of recombinant mature hormone in suitable hosts and secretion of this therapeutic protein into the extracellular space can be considered as one of the best cost-effective approaches not only to obtain the active form of the protein but also endotoxin-free preparation. Since the natural growth hormone signal peptide is of eukaryotic origin and is not detectable by any of the Escherichia coli secretory systems, including Sec and Tat, and is therefore unable to secrete hGH in the prokaryotic systems, designing a new and efficient signal peptide is essential to direct hGh to the extracellular space.ResultsIn this study, using a combination of the bioinformatics design and molecular genetics, the protein A signal peptide from Staphylococcus aureus was modified, redesigned and then fused to the mature hGH coding region. The recombinant hGH was then expressed in E. coli and successfully secreted to the medium through the Sec pathway. Secretion of the hGH into the medium was verified using SDS-PAGE and western blot analysis. Recombinant hGH was then expressed in E. coli and successfully secreted into cell culture medium via the Sec pathway. The secretion of hGH into the extracellular medium was confirmed by SDS-PAGE and Western blot analysis. Furthermore, the addition of glycine was shown to improve hGH secretion onto the culture medium. Equations for determining the optimal conditions were also determined. Functional hGH analysis using an ELISA-based method confirmed that the ratio of the active form of secreted hGH to the inactive form in the periplasm is higher than this ratio in the cytoplasm.ConclusionsSince the native signal protein peptide of S. aureus protein A was not able to deliver hGH to the extracellular space, it was modified using bioinformatics tools and fused to the n-terminal region of hGh to show that the redesigned signal peptide was functional.

Active acromegaly is associated with enhanced left ventricular contractility: Results from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study

IntroductionAcromegaly is a relatively rare chronic hormonal disease resulting in disfigurement. In 90% of cases, acromegaly is caused by a benign pituitary monoclonal human growth hormone-secreting tumor. The aim of the present study was to determine the presence of left ventricular (LV) deformation abnormalities using three-dimensional speckle-tracking echocardiography in a group of acromegalic patients. MethodsThirty-eight acromegalic patients were involved in the study. Thirteen patients were excluded due to inadequate image quality. The mean age of the remaining patients was 57.2±13.6 years and seven were male. Their data were compared to an age- and gender-matched control population, which consisted of 34 healthy volunteers (mean age: 52.7±4.9 years, 15 male). ResultsGlobal and mean segmental LV radial strain (RS) (33.2±13.4% vs. 25.2±10.8%, p=0.01 and 36.0±12.1% vs. 28.2±10.0%, p=0.009, respectively) proved to be significantly higher in acromegaly compared to controls. Active acromegalic patients had significantly higher global and mean segmental LV-RS (35.5±14.4% vs. 25.2±10.8%, p=0.03 and 37.9±13.3% vs. 28.2±10.0%, p=0.03, respectively) compared to controls. Between the active and inactive acromegaly groups, only basal LV circumferential strain (-30.2±4.8% vs. -26.7±4.1%, p=0.02) was found to be significantly different. ConclusionThe presented clinical, demographic, therapeutic and echocardiographic features demonstrate that active acromegaly is associated with enhanced LV RS as compared to healthy controls and those with inactive acromegaly.

Model informed quantification of the feed-forward stimulation of growth hormone by growth hormone-releasing hormone.

AimsGrowth hormone (GH) secretion is pulsatile and secretion varies highly between individuals. To understand and ultimately predict GH secretion, it is important to first delineate and quantify the interaction and variability in the biological processes underlying stimulated GH secretion. This study reports on the development of a population nonlinear mixed effects model for GH stimulation, incorporating individual GH kinetics and the stimulation of GH by GH‐releasing hormone (GHRH).MethodsLiterature data on the systemic circulation, the median eminence, and the anterior pituitary were included as system parameters in the model. Population parameters were estimated on data from 8 healthy normal weight and 16 obese women who received a 33 μg recombinant human GH dose. The next day, a bolus injection of 100 μg GHRH was given to stimulate GH secretion.ResultsThe GH kinetics were best described with the addition of 2 distribution compartments with a bodyweight dependent clearance (increasing linearly from 24.7 L/h for a 60‐kg subject to 32.1 L/h for a 100‐kg subject). The model described the data adequately with high parameter precision and significant interindividual variability on the GH clearance and distribution volume. Additionally, high variability in the amount of secreted GH, driven by GHRH receptor activation, was identified (coefficient of variation = 90%).ConclusionThe stimulation of GH by GHRH was quantified and significant interindividual variability was identified on multiple parameters. This model sets the stage for further development of by inclusion of additional physiological components to quantify GH secretion in humans.

The right atrium in acromegaly-a three-dimensional speckle-tracking echocardiographic analysis from the MAGYAR-Path Study.

Acromegaly is a chronic, rare hormonal disease associated with major cardiovascular co-morbidities. The disease, in the majority of the cases, is caused by a benign human growth hormone (hGH) secreting adenoma. Cardiovascular involvement is especially common in acromegalic patients from the most common hypertension to cardiomyopathy. Left ventricular hypertrophy and myocardial fibrosis are considered common findings in acromegalic cardiomyopathy, which might result in severe heart failure at end-stages. It was set out to quantify right atrial (RA) morphology and function in a group of acromegalic patients using three-dimensional (3D) speckle-tracking echocardiography (3DSTE). The study comprised 30 patients from which 8 patients were excluded due to inadequate image quality. Mean age of the remaining acromegaly patients were 53.7±14.5 years (7 males). In the control group 44 healthy adults were enrolled (mean age: 50.7±12.6 years, 15 males). In each case, complete two-dimensional Doppler echocardiography was performed followed by 3DSTE. All three RA volumetric parameters (Vmax, Vmin, VpreA) were significantly higher in case of acromegaly compared to the healthy controls. Strain analysis revealed that RA function may be enhanced in acromegalic patients, which is more notable in case of active acromegaly. Numerous independent strain parameters had significant correlations with different hormonal variables in the active acromegaly group. These correlations were not present in the inactive acromegaly subgroup. Acromegaly has a profound effect on RA function and with proper treatment these changes partly seem to be reversible.

P946 Right atrial volumetric and functional analysis by three-dimensional speckle-tracking echocardiography in acromegaly

Abstract Introduction Acromegaly is a chronic, rare hormonal disease associated with major cardiovascular comorbidities. The disease, in the majority of the cases, is caused by a benign human growth hormone secreting adenoma. Cardiovascular involvement is especially common in acromegaly patients from the most common hypertension to cardiomyopathy. It was set out to quantify right atrial (RA) morphology and function in a group of acromegaly patients using three-dimensional (3D) speckle-tracking echocardiography (3DSTE). Methods The study comprised 30 patients from which 8 patients were excluded due to inadequate image quality. Mean age of the remaining acromegaly patients were 53.7 ± 14.5 years (7 males). Ten patients were in active phase, while 12 subjects had inactive acromegaly. In the control group 40 healthy adults were enrolled (mean age: 52.3 ± 8.2 years, 15 males). In each case, complete two-dimensional Doppler echocardiography was performed followed by 3DSTE. Results Maximum (54.5 ± 14.4 ml vs. 47.2 ± 11.6 ml, p <0.05) and minimum (35.5 ± 10.2 ml vs. 29.2 ± 9.1 ml, p <0.05) RA volumes and RA volume before atrial contraction (45.1 ± 11.1 ml vs. 38.2 ± 10.3 ml, p <0.05) were significantly higher in case of acromegaly compared to the healthy controls. Both global and mean segmental peak 3D strain (-11.94 ± 7.52% vs. -8.07 ± 5.03%, p <0.05 and -17.16 ± 6.13% vs. -13.78 ± 5.35%, p <0.05) were higher in the acromegaly group compared to the controls. At atrial contraction, mean segmental radial strain (-13.22 ± 6.45% vs. -9.74 ± 4.58%, p <0.05) was significantly higher and mean segmental 3D strain (-9.78 ± 5.44% vs. -13.78 ± 5.35%, p <0.05) was significantly lower in the acromegaly group compared to the controls. Between the active and inactive group of acromegaly patients, mean segmental longitudinal strain (28.17 ± 4.89% vs. 35.34 ± 9.75%, p <0.05) was significantly different. Numerous independent strain parameters had significant correlations with different hormonal variables in the active acromegaly group. These correlations were not present in the inactive acromegaly subgroup. Conclusion Acromegaly is associated with significant RA volumetric and functional abnormalities.

P1795 Active acromegaly is associated with enhanced left ventricular contractility - A three-dimensional speckle-tracking echocardiographic study

Abstract Introduction Acromegaly is a relatively rare, chronic hormonal disease resulting in disfigurement. In 90% of the cases, acromegaly is caused by a benign pituitary monoclonal human growth hormone-secreting tumor. Hypertension and left ventricular (LV) hypertrophy are the most common cardiovascular comorbidites, but serious valvular regurgitation and heart failure could also develop at the end-stages. The aim of the present study was to determine the presence of LV deformational abnormalities using three-dimensional speckle-tracking echocardiography (3DSTE) in a group of acromegaly patients. Methods Thirty-eight acromegaly patients were involved in the present study. Thirteen patients were excluded due to inadequate image quality. The mean age of the remaining patients were 57.2 ± 13.6 years (7 males). The active acromegaly subgroup consisted of 14 patients (mean age: 58.6 ± 14.6 years, 5 males), while the inactive group contained 11 patients (mean age: 54.0 ± 12.9, 2 males). Their data was compared to an age- and gender matched control population, which comprised of 34 healthy volunteers (mean age: 52.7 ± 4.9 years, 15 males). All subjects have undergone complete two-dimensional Doppler echocardiography extended with 3DSTE. Results Significant differences in left atrial diameter and volume, LV end-diastolic diameter and volume, interventricular septum and LV posterior wall thickness could be demonstrated between the acromegaly group and healthy controls. Global and mean segmental 3DSTE-derived LV radial strain (RS)(33.2 ± 13.4% vs. 25.2 ± 10.8%, p =0.01 and 36.0 ± 12.1% vs. 28.2 ± 10.0%, p =0.009, respectively) proved to be significantly higher in acromegaly patients compared to controls. Active acromegaly patients had a significantly higher global and mean segmental RS (35.5 ± 14.4% vs. 25.2 ± 10.8%, p =0.03 and 37.9 ± 13.3% vs. 28.2 ± 10.0%, p =0.03, respectively) as compared to that of controls. Between active and inactive acromegaly groups only basal LV circumferential strain (-30.2 ± 4.8% vs. -26.7 ± 4.1%, p =0.02) was found to be significantly different. Conclusion With presented clinical, demographic, therapeutic and echocardiographic features, active acromegaly is associated with enhanced LV-RS as compared to the healthy population.

The cysteine-rich domain of synaptosomal-associated protein of 23 kDa (SNAP-23) regulates its membrane association and regulated exocytosis from mast cells

Synaptosomal-associated protein of 23 kDa (SNAP-23) plays an important role during regulated exocytosis of various inflammatory mediators, stored in secretory granules, from mast cells in response to physiological triggers. It is however synthesized as a soluble protein, and the mechanisms by which free SNAP-23 gets peripherally associated with membrane for the regulation of exocytosis, are poorly defined. SNAP-23 contains a hydrophobic domain with five closely spaced cysteines which get palmitoylated, and we show that SNAP-23 cysteine mutants show differential membrane association when transfected in rat basophilic leukemia (RBL) mast cells. SNAP-23 Cys− mutant, devoid of all five cysteines, and SNAP-23 P119A (proline to alanine) mutant, that likely interferes with palmitoylation of SNAP-23 by palmitoyl transferases are completely cytosolic. Mutating specific cysteines (Cys; C) to leucine or phenylalanine (L or F; retains hydrophobicity but lacks palmitoylation) partially decreases the membrane association of SNAP-23 which is further hampered by alanine (A; has lesser hydrophobicity, and lacks palmitoylation) mutation at C79, C80 or C83 position. Cloning a transmembrane domain MDR31–145 from multidrug resistance protein into SNAP-23 Cys− mutant is able to partially restore its membrane association. Regulated exocytosis studies using co-transfected human growth hormone (hGH) secretion reporter plasmid revealed that overexpression of SNAP-23 Cys− and P119A mutants significantly inhibits the overall extent of exocytosis from RBL mast cells, whereas expression of SNAP-23 Cys−-MDR31–145 fusion protein is able to restore exocytosis. These results establish that the cysteine-rich domain of SNAP-23 regulates its membrane association and thereby also regulates exocytosis from mast cells.

Identification of a novel growth hormone releasing peptide (a glycine analogue of GHRP-2) in a seized injection vial.

Growth hormone releasing peptides (GHRPs) are synthetic peptides with the ability to stimulate human growth hormone (hGH) secretion. Several GHRPs have been developed as drug candidates; however, only one of them, GHRP-2 (Pralmorelin), has received a clinical approval. Nevertheless, they are distributed on the black market and misused by cheating athletes, due to their performance-enhancing effects. Hence, GHRPs have been included in the World-Anti-Doping-Agency's Prohibited List as forbidden substances in sport. Predominantly, analytical methods for detection and unequivocal identification of doping substances are based on mass spectrometry. Therefore, in the present work, a qualitative analysis by liquid chromatography coupled to high-resolution tandem mass spectrometry with a quadrupole time-of-flight analyzer was performed to identify a new heptapeptide (MW=874.02Da) - a glycine analogue of GHRP-2. Structure determination using de novo sequencing is described here in detail. The results of this study may indicate a new approach to circumvent a detection of doping practices.

Escherichia coli "TatExpress" strains super-secrete human growth hormone into the bacterial periplasm by the Tat pathway.

Numerous high‐value proteins are secreted into the Escherichia coli periplasm by the General Secretory (Sec) pathway, but Sec‐based production chassis cannot handle many potential target proteins. The Tat pathway offers a promising alternative because it transports fully folded proteins; however, yields have been too low for commercial use. To facilitate Tat export, we have engineered the TatExpress series of super‐secreting strains by introducing the strong inducible bacterial promoter, ptac, upstream of the chromosomal tatABCD operon, to drive its expression in E. coli strains commonly used by industry (e.g., W3110 and BL21). This modification significantly improves the Tat‐dependent secretion of human growth hormone (hGH) into the bacterial periplasm, to the extent that secreted hGH is the dominant periplasmic protein after only 1 hr induction. TatExpress strains accumulate in excess of 30 mg L−1 periplasmic recombinant hGH, even in shake flask cultures. A second target protein, an scFv, is also shown to be exported at much higher rates in TatExpress strains.

Do anabolic nutritional supplements stimulate human growth hormone secretion in elderly women with heart failure?

Growth hormone treatment has gained attention over the past decade as a treatment for heart failure. Human growth hormone (HGH) must be administered by injections (usually daily), so there is considerable advantage to stimulation of endogenous secretion by amino acid‐based nutritional supplementation. However, studies investigating the effect of amino acid (AA) supplementation show conflicting results. Therefore, in this study we aimed to investigate the effect of nutritional supplementation on HGH production in elderly women with heart failure. Eight elderly women with heart failure participated in this randomized cross‐over study. Plasma HGH concentration was measured before and for 4 h following ingestion of a mixture of protein, carbohydrate, and fat or an AA beverage. HGH concentration was determined with ELISA kits and AA concentrations were analyzed by Liquid Chromatography–Mass Spectrometry (LCMS). Linear mixed models was performed to analyze the effect of time, treatment, and interaction. Plasma arginine and lysine concentrations were significantly higher after consumption of the AA drink compared to the mixture of protein, carbohydrate, and fat. Nonetheless, only ingestion of the protein, carbohydrate, and fat mixture (meal replacement) increased HGH concentration. HGH concentration was increased in elderly women with heart failure following consumption of a meal replacement containing protein, carbohydrate, and fat. Consumption of a mixture of amino acids failed to increase HGH concentration despite significantly greater elevations in plasma amino acid concentrations, including arginine and lysine. The stimulatory effect of the protein/carbohydrate/fat mixture was presumably mediated by factors other than increases in free amino acid concentrations.

Establishment of a protocol to extend the lifespan of human hormone-secreting pituitary adenoma cells.

The aim of this study was to generate immortalized human anterior pituitary adenoma cells. Reliable cell models for the study of human pituitary adenomas are as yet lacking and studies performed so far used repeated passaging of freshly excised adenomas, with the attendant limitations due to limited survival in culture, early senescence, and poor reproducibility. We devised a technique based upon repeated co-transfections of two retroviral vectors, one carrying the catalytic subunit of human telomerase, hTERT, the other SV40 large T antigen. This approach extended the lifespan of cells derived from a human growth hormone-secreting adenoma up to 18 months while retaining morphology of primary cells, growth hormone synthesis and growth hormone secretion. Our attempt represents the first demonstration of successful lifespan extension of human growth hormone-secreting pituitary adenoma cells via co-transfection of hTERT and SV40T and paves the way to future attempts to obtain stable cell lines.

MP76-09 GROWTH HORMONE RELEASING PEPTIDE TREATMENT IN MEN INCREASES SERUM INSULIN-LIKE GROWTH FACTOR-1 LEVELS

You have accessJournal of UrologySexual Function/Dysfunction: Medical, Hormonal & Non-surgical Therapy I1 Apr 2016MP76-09 GROWTH HORMONE RELEASING PEPTIDE TREATMENT IN MEN INCREASES SERUM INSULIN-LIKE GROWTH FACTOR-1 LEVELS John T. Sigalos, Andrew Allison, Alexander Pastuszak, Samuel J. Ohlander, Amin Herati, Mark C. Lindgren, and Larry I. Lipshultz John T. SigalosJohn T. Sigalos More articles by this author , Andrew AllisonAndrew Allison More articles by this author , Alexander PastuszakAlexander Pastuszak More articles by this author , Samuel J. OhlanderSamuel J. Ohlander More articles by this author , Amin HeratiAmin Herati More articles by this author , Mark C. LindgrenMark C. Lindgren More articles by this author , and Larry I. LipshultzLarry I. Lipshultz More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1860AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Stimulation of growth hormone (GH) secretion, rather than administration of exogenous GH, which is severely limited by FDA regulations, may afford a safer approach to obtaining the benefits of GH while avoiding the adverse effects associated with exogenous GH. Few studies have evaluated the effects of GH secretagogues on GH and insulin-like growth factor-1 (IGF-1) secretion in humans. These GH secretagogues include GH releasing peptides (GHRP) GHRP-2 and GHRP-6, and the GH releasing hormone (GHRH) analogue, sermorelin (SERM). IGF-1 serves as a surrogate marker for GH production. Here we present data evaluating the impact of GHRP/SERM therapy on IGF-1 levels. METHODS A retrospective review of medical records was performed for 105 men already on testosterone therapy seeking gains in lean body mass who were prescribed GHRP-6, GHRP-2, and SERM 3 times daily in a dose of 100 mcg of each peptide. Serum IGF-1 level were assessed in response to treatment. To gauge efficacy and compliance, study inclusion criteria included 1) evidence of drug use, assessed via frequency of prescription fills, 2) interval lab testing every 3-4 months, 3) a low-normal baseline IGF-1 (<200 ng/ml). After assessment, the 14 men who met inclusion criteria were evaluated. RESULTS Mean (SD) age within the cohort (n=14) was 33.2 (2.9) years, and baseline serum IGF-1 level was 159.5 (26.7) ng/ml. Mean (SD) duration of continuous GHRH/GHRP treatment was 134 (88) days. Post treatment IGF-1 level was 239 (54.6) ng/ml (p<0.0001). 4 of 11 men were co-administered an aromatase inhibitor and/or tamoxifen due to elevated estradiol (E2) levels and/or gynecomastia during treatment. Interestingly, decreasing E2 production or estrogen receptor blockade had a negative effect on IGF-1 production (Figure 1). CONCLUSIONS Combination therapy with GHRP-6, GHRP-2, and SERM increases serum IGF-1 levels. This effect is observed with strict compliance to 3 times daily dosing. Increases in serum IGF-1 while on treatment approached the upper limits of our laboratory reference range (250 ng/ml), but were inhibited by blocking estrogen action. Taken together, our results suggest that combination therapy with GHRP-6, GHRP-2, and SERM may be beneficial in wasting conditions. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e1010 Advertisement Copyright & Permissions© 2016MetricsAuthor Information John T. Sigalos More articles by this author Andrew Allison More articles by this author Alexander Pastuszak More articles by this author Samuel J. Ohlander More articles by this author Amin Herati More articles by this author Mark C. Lindgren More articles by this author Larry I. Lipshultz More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Effect of GenF20 Plus on serum IGF-1 levels in healthy adults: a randomized controlled study

Effect of GenF20 Plus on serum IGF-1 levels in healthy adults: a randomized controlled study Navneet Sonawane,1 Vinayak Kale,2 Suhas Erande,3 Jayesh Chaudhary1 1Vedic Lifesciences Pvt Ltd, Mumbai, India; 2Lokmanya Hospital, Pune, India; 3Akshay Hospital, Pune, India Background: Aging is related to a reduction of growth hormones, resulting in physiological derailment and affects overall wellbeing. GenF20 Plus is a dietary supplement postulated to naturally stimulate the secretion of human growth hormone (HGH) through the anterior pituitary. This study sought to evaluate the effect of GenF20 Plus in enhancing the levels of insulin-like growth factor-1 (IGF-1), which is a marker of HGH levels. Methods: Seventy subjects aged 35&ndash;65 years visiting outpatient departments at five study centers across India, presenting with at least two of the following age-related complaints: decreased memory, decreased libido, low energy levels, or poor quality of sleep were randomly assigned to either GenF20 Plus (n=35) or placebo (n=35) for a period of 12 weeks (84 days). Randomization was carried out using computerized software. The primary outcome measure was serum IGF-1 levels. Changes in waist circumference, body mass index, body fat percentage, lean muscle mass, and scores for memory, libido, energy levels, and quality of sleep were also assessed. Trial registration: CTRI/2011/06/001784. Results: Sixty-one subjects completed the study as per protocol and were analyzed. The mean increase (mean &plusmn; standard deviation) in IGF-1 levels at day 84 in the GenF20 Plus group was 13.46&plusmn;36.12 ng/mL and in the placebo group was 6.35&plusmn;36.56 ng/mL, which was not statistically significantly different (P&gt;0.05) when compared across the groups. In the &ge;40 years subgroup, the mean increase in IGF-1 in the GenF20 Plus group (14.59&plusmn;40.08 ng/mL) was not statistically significantly different when compared to the placebo group (3.17&plusmn;16.09 ng/mL) using analysis of variance (ANOVA; P&gt;0.05). However, when this change was analyzed using analysis of covariance (ANCOVA) considering baseline values as the covariates, it was found to be statistically significantly different (GenF20 Plus: 22.69&plusmn;40.62 ng/mL, placebo: -4.31&plusmn;16.79 ng/mL; P&lt;0.05). The changes in IGF-1 values in the &lt;40 years subgroup were not found to be statistically significant. No statistically significant difference over placebo was seen for the other variables. Conclusion: GenF20 Plus increased serum IGF-1 levels in subjects &ge;40 years of age who physiologically have reduced IGF-1 levels. However, significant changes in other parameters were not seen, probably due to the short duration of treatment. Further studies with longer treatment duration and large sample size are warranted to understand the clinical benefits of GenF20 Plus, especially in adults above 40 years of age. Keywords: IGF-1, herbal supplement, human growth hormone, HGH, aging&nbsp;

Efficient transfection of dissociated mouse chromaffin cells using small-volume electroporation

We have developed an improved procedure for isolating and transfecting a chromaffin cell-enriched population of primary cells from adult mouse adrenal glands. Significantly, the parameters of a novel electroporation transfection technique were optimized to achieve an average transfection efficiency of 45% on the small number of cells derived from the mouse glands. Such transfection efficiency was previously unachievable with the electroporation protocols conventionally used with bovine chromaffin cells, even with use of large cell numbers. Our small scale technique now makes feasible the use of genetically homogenous inbred mouse models for investigations on the exocytotic pathway without the time, expense, and cellular changes associated with viral approaches. High fidelity co-expression of multiple plasmids in individual cells is a further advantage of the procedure. To assess whether the biophysical characteristics of mouse adrenal chromaffin cells were altered by this process, we examined structural integrity using immunocytochemistry and functional response to stimuli using calcium imaging, amperometry, and whole-cell capacitance and current clamp recordings. We conclude these parameters are minimally affected. Finally, we demonstrate that high transfection efficiency makes possible the use of primary mouse adrenal chromaffin cells, rather than a cell line, in human growth hormone secretion assays for high throughput evaluation of secretion.

Toward gene therapy for growth hormone deficiency via salivary gland expression of growth hormone

Salivary glands are useful targets for gene therapeutics. After gene transfer into salivary glands, regulated secretory pathway proteins, such as human growth hormone, are secreted into saliva, whereas constitutive secretory pathway proteins, such as erythropoietin, are secreted into the bloodstream. Secretion of human growth hormone (hGH) into the saliva is not therapeutically useful. In this study, we attempted to redirect the secretion of transgenic hGH from the saliva to the serum by site-directed mutagenesis. We tested hGH mutants first in vitro with AtT20 cells, a model endocrine cell line that exhibits polarized secretion of regulated secretory pathway proteins. Selected mutants were further studied in vivo using adenoviral-mediated gene transfer to rat submandibular glands. We identified two mutants with differences in secretion behavior compared to wild-type hGH. One mutant, ΔN1-6 , was detected in the serum of transduced rats, demonstrating that expression of this mutant in the salivary gland resulted in its secretion through the constitutive secretory pathway. This study demonstrates that mutagenesis of therapeutic proteins normally destined for the regulated secretory pathway may result in their secretion via the constitutive secretory pathway into the circulation for potential therapeutic benefit.