Evaluation of the Biological Properties and the Enzymatic Stability of Glycosylated Luteinizing Hormone-Releasing Hormone Analogs

Moradi, Shayli Varasteh; Varamini, Pegah; Tóth, István

doi:10.1208/s12248-015-9769-x

Cited by 9 publications

(7 citation statements)

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“…Mutation of glycosylation sites of the N152Q and N173Q not only decreased the ligand binding affinity but also suppress the LHR protein expression on cell surface (Clouser and Menon, 2005). LH releasing hormone (LHRH) was more stabilized and increased half-life after glycosylation in plasma or tissue homogenates (Moradi et al, 2015). Moreover, it is possible to elevate LHR functional efficiency after glycosylation (Liu et al, 1989;Zhang et al, 1995;Lin et al, 2008).…”

Section: Discussionmentioning

confidence: 99%

Interactive Effect of Corticosterone and Lactate on Regulation of Testosterone Production in Rat Leydig Cells

Chen¹,

Chen²,

Lin³

et al. 2017

Journal Cellular Physiology

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The increasing intensity of exercise enhanced corticosterone and lactate production in both humans and rodents. Our previous studies also demonstrated that lactate could stimulate testosterone production in vivo and in vitro. However, the production of testosterone in response to combined corticosterone and lactate on Leydig cells, and underlying molecular mechanisms are remained unclear. This study investigated the changes in testosterone levels of Leydig cells upon exposure to lactate, corticosterone or combination of both, and revealed the detailed mechanisms. Leydig cells were isolated from rat testes, and treated with different concentrations of lactate (2.5-20 mM), cortiosterone (10 -10 M) and lactate plus corticosterone. The production of testosterone were assayed by radioimmunoassay, and the key molecular proteins, including luteinizing hormone receptor (LHR), protein kinase A (PKA), steroidogenic acute regulatory protein (StAR), and cholesterol P450 side-chain cleavage enzyme (P450scc) involved in testosterone production were performed by Western blot. Results showed that testosterone levels were significantly increased with lactate, while decresed with corticosterone and lactate plus corticosterone treatment. Protein expressions of LHR and P450scc were upregulated with lactate treatment. However, PKA and P450scc were downregulated by lactate plus corticosterone treatment. This downregulation was followed by decreased testoterone levels in Leydig cells. Furthermore, acetylated cAMP, which activates testosterone production was increased with lactate, but not altered by conrtiosterone. Our findings conclude that corticosterone may interfere with lactate, and restrict lactate-stimulated testosterone production in Leydig cells. J. Cell. Physiol. 232: 2135-2144, 2017. © 2016 Wiley Periodicals, Inc.

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Section: Discussionmentioning

confidence: 99%

Interactive Effect of Corticosterone and Lactate on Regulation of Testosterone Production in Rat Leydig Cells

Chen¹,

Chen²,

Lin³

et al. 2017

Journal Cellular Physiology

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“…(Moradi et al, 2015b) The cells were passaged and plated (90 μL/well) in flat-bottomed 96-well plates at 2 × 10 5 cells/mL for LNCaP, DU145 and OVCAR-3 or 1 × 10 5 cells/mL for PC3 and SKOV-3 cells. Compounds were used at a final concentration of 1, 10, 25, 50 or 100 µM in 0.5% DMSO in the culture media (n = 3/compound, in at least 3 independent experiments).…”

Section: Tumor Cell Proliferation Assay (Mtt Assay)mentioning

confidence: 99%

“…(Moradi et al, 2015b) Cells were plated at 4 × 10 5 cells/mL in 96-well plates at a density of 3 × 10 4 cells/well and incubated for 72 h at 37 ºC.…”

Section: Rat Pituitary Cell Preparationmentioning

confidence: 99%

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New gonadotropin-releasing hormone glycolipids with direct antiproliferative activity and gonadotropin-releasing potency

Varamini

Mansfeld

Giddam

et al. 2017

International Journal of Pharmaceutics

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Graphical abstractGonadotropin-releasing hormone (GnRH) is an endogenous peptide with a short biological half-life. Although GnRH analogs (eg. triptorelin) are developed with enhanced stability compared to the native peptide, they still suffer from poor biological stability and pharmacokinetic properties. Furthermore, they are only effective in the treatment of hormone-dependent reproductive cancers. In this study we applied lipidation and glycosylation along with D-amino acid substitution at position 6 (D-Trp 6 ) to improve the stability, permeability, and consequently the potency of the GnRH peptide and triptorelin. We showed that the conjugation of GnRH with a lipid moiety and carbohydrates made all modified constructs (1-8) more stable than the parent peptide against enzymatic degradation (5.5 to 6.5 times). Two of the lactose-modified glycolipopeptides, 3 and 6, showed 27 and 16 times higher membrane permeability than the parent GnRH, respectively. All analogs with D-Trp 6 -substitution (4-6) exerted GnRH receptor-mediated antiproliferative activity in prostate and ovarian GnRH-receptor positive cell lines. They were more potent than triptorelin in the hormone-independent prostate cancer cell line: DU145. Compound 6 (lactose-modified) was the most potent analog for stimulating the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) gonadotropins from rat pituitary cells in vitro. The same glycolipopeptide exhibited a higher efficacy and duration of action in stimulating the release of LH than triptorelin in a preclinical mouse model. The superior activity 2 of lipid-and carbohydrate-substituted triptorelin analog 6 made it a promising candidate for the development of new GnRH agonists to treat both hormone-dependent and hormone-refractory prostate cancer..LIST OF ABBREVIATIONS

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“…- [122] - [33,56,120,121] 4 Corticotrophins - [124] - [123] 5 Growth hormone (GH), Insulinlike growth factors (e.g. IGF-1), Mechano Growth Factors (MGFs), etc.…”

Section: Introductionmentioning

confidence: 99%

Annual banned‐substance review: analytical approaches in human sports drug testing

Thevis

Kuuranne

Walpurgis

et al. 2016

Drug Testing and Analysis

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The aim of improving anti-doping efforts is predicated on several different pillars, including, amongst others, optimized analytical methods. These commonly result from exploiting most recent developments in analytical instrumentation as well as research data on elite athletes' physiology in general, and pharmacology, metabolism, elimination, and downstream effects of prohibited substances and methods of doping, in particular. The need for frequent and adequate adaptations of sports drug testing procedures has been incessant, largely due to the uninterrupted emergence of new chemical entities but also due to the apparent use of established or even obsolete drugs for reasons other than therapeutic means, such as assumed beneficial effects on endurance, strength, and regeneration capacities. Continuing the series of annual banned-substance reviews, literature concerning human sports drug testing published between October 2014 and September 2015 is summarized and reviewed in reference to the content of the 2015 Prohibited List as issued by the World Anti-Doping Agency (WADA), with particular emphasis on analytical approaches and their contribution to enhanced doping controls.

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Evaluation of the Biological Properties and the Enzymatic Stability of Glycosylated Luteinizing Hormone-Releasing Hormone Analogs

Cited by 9 publications

References 54 publications

Interactive Effect of Corticosterone and Lactate on Regulation of Testosterone Production in Rat Leydig Cells

Interactive Effect of Corticosterone and Lactate on Regulation of Testosterone Production in Rat Leydig Cells

New gonadotropin-releasing hormone glycolipids with direct antiproliferative activity and gonadotropin-releasing potency

Annual banned‐substance review: analytical approaches in human sports drug testing

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