Single-chain human follicle-stimulating hormone with a di-N-glycosylated linker.

The classic way to produce single-chain (sc) glycoprotein hormones is to fuse their two subunits through the carboxy-terminal peptide (CTP) from human Choriogonadotropin (hCG). The CTP confers a longer half-life to single-chain hormones thanks to its four O-glycosyl side chains. However, unlike syncytiotrophoblastic cells, most cells used for recombinant protein production do not transfer O-glycosyl chains efficiently.

Anthropogenic particle abundance and characteristics in seawater and intertidal sediments of the Tonkin Bay Coast (North Vietnam).

Microplastics (MPs, plastic items from 1 µm to 5 mm in size) are present in all environmental compartments. The evaluation of their concentration, fate, and spatial distribution is still a challenge for the scientific community. This concern is just debuting in developing countries, (i.

Highly-Sensitive In Vitro Bioassays for FSH, TSH, PTH, Kp, and OT in Addition to LH in Mouse Leydig Tumor Cell.

We demonstrate here that highly sensitive in vitro bioassays for FSH, TSH, and PTH can be set up in mouse Leydig Tumor Cells (mLTC), in addition to the normal LH/CG bioassay, after they were transfected with expression vectors encoding the corresponding Gs Protein-Coupled Receptors (GsPCR), such as FSHR, TSHR, or PTHR. Although the β2 adrenergic receptor is also a GsPCR, its expression in mLTC led to a significant but very low cAMP response compared to those observed with FSH, TSH, or PTH. Similarly, after transfection of the GiPCR MT1 melatonin receptor, we did not observe any inhibitory effect by melatonin of the LH or hCG stimulation.

Undissociable chemically cross-linked and single-chain gonadotropins.

Undissociable gonadotropins can be obtained either by chemical cross-linking of the natural heterodimeric hormones or by expressing recombinant single-chain molecules through the fusion of their α and β polypeptide sequences. These undissociable hormones are not more active than their natural heterodimeric counterparts indicating that the β-subunit seatbelt embracing the α-subunit ensures the αβ heterodimer stability in physiological conditions. The main interests of single-chain gonadotropins are that 1/only one single plasmid is required to produce an active recombinant hormone, 2/the two subunits' domains are constantly present in equal amounts and 3/they remain in close proximity even at low concentration for forming the hormone bioactive 3D structure.

Membrane Hormone Receptors and Their Signaling Pathways as Targets for Endocrine Disruptors.

The endocrine disruptors are mostly small organic molecules developed for numerous and very diverse industrial applications. They essentially act through nuclear receptors with small and hydrophobic endogenous ligands. Nevertheless, potential adverse effects through membrane hormone receptors cannot be ruled out, and have indeed been observed.

Improving the Utility of a Dynorphin Peptide Analogue Using Mannosylated Glycoliposomes.

Peptide therapeutics offer numerous advantages in the treatment of diseases and disorders of the central nervous system (CNS). However, they are not without limitations, especially in terms of their pharmacokinetics where their metabolic lability and low blood-brain barrier penetration hinder their application. Targeted nanoparticle delivery systems are being tapped for their ability to improve the delivery of therapeutics into the brain non-invasively.

Effect of Soluble Adenylyl Cyclase (ADCY10) Inhibitors on the LH-Stimulated cAMP Synthesis in Mltc-1 Leydig Cell Line.

In contrast to all transmembrane adenylyl cyclases except ADCY9, the cytosolic soluble adenylyl cyclase (ADCY10) is insensitive to forskolin stimulation and is uniquely modulated by calcium and bicarbonate ions. In the present paper, we focus on ADCY10 localization and a kinetic analysis of intracellular cAMP accumulation in response to human LH in the absence or presence of four different ADCY10 inhibitors (KH7, LRE1, 2-CE and 4-CE) in MTLC-1 cells. ADCY10 was immuno-detected in the cytoplasm of MLTC-1 cells and all four inhibitors were found to inhibit LH-stimulated cAMP accumulation and progesterone level in MLTC-1 and testosterone level primary Leydig cells.

Fluoxetine affects cytosolic cAMP, ATP, Ca responses to forskolin, and survival of human ovarian granulosa tumor COV434 cells.

Fluoxetine (FLX), a selective serotonin reuptake inhibitor antidepressant, exhibits various other mechanisms of action in numerous cell types and has been shown to induce cell death in cancer cells, paving the way for its potential use in cancer therapy. The aim of this study was to determine the off-target effects of the anti-depressant drug FLX, on the human ovarian granulosa tumor COV434 cells stimulated by forskolin (FSK), by measuring the real-time kinetics of intracellular cyclic AMP (cAMP), ATP level, cytoplasmic calcium ([Ca]) and survival of COV434 cells. We show that incubating COV434 cells with FLX (between 0.

Cell Communications among Microorganisms, Plants, and Animals: Origin, Evolution, and Interplays.

Cellular communications play pivotal roles in multi-cellular species, but they do so also in uni-cellular species. Moreover, cells communicate with each other not only within the same individual, but also with cells in other individuals belonging to the same or other species. These communications occur between two unicellular species, two multicellular species, or between unicellular and multicellular species.

Adiponectin: Role in Physiology and Pathophysiology.

Adiponectin, an adipokine secreted by adipocytes, is a well-known homeostatic factor for regulating glucose levels, lipid metabolism, and insulin sensitivity through its anti-inflammatory, anti-fibrotic, and antioxidant effects. All these metabolic processes are mediated via two adiponectin receptors, AdipoR1 and AdipoR2. In addition, adiponectin is one of the hormones with the highest plasma concentrations.

Mannosylated glycoliposomes for the delivery of a peptide kappa opioid receptor antagonist to the brain.

Dynantin is a potent and selective synthetic polypeptide kappa opioid receptor antagonist which has potential antidepressant and anxiolytic-like therapeutic applications, however its clinical development has been hampered by plasma stability issues and poor penetration of the blood brain barrier. Targeted liposome delivery systems represent a promising and non-invasive approach to improving the delivery of therapeutic agents across the blood brain barrier. As part of our work focused on targeted drug delivery, we have developed a novel mannosylated liposome system.

Opiate Intoxication Caused by Epidural Infusion of Morphine: A Case Report of a Near Fatal Medication Error.

Introduction: Epidural infusion of local anesthetics with opioids is widely used for pain control during the perioperative-and peripartum-periods. Selection of the opioid, appropriate dosing, and follow-up by the acute pain service are critical in providing safe postoperative epidural analgesia.

Case Report Summary: A 71-year-old man was scheduled for a parastomal hernia repair with midline laparotomy.

New insights in the AMPK regulation in chicken spermatozoa: Role of direct AMPK activator and relationship between AMPK and PKA pathways.

Energy balance is an important feature for spermatozoa functions. The 5'-AMP-activated protein kinase (AMPK), a sensor of cell energy, has been implicated as a mediator between spermatozoa functions and energy balance. We recently identified and localized the AMPK protein in chicken spermatozoa and showed that its activation with non-specific activators significantly modified spermatozoa quality.

Estrogenic Compounds or Adiponectin Inhibit Cyclic AMP Response to Human Luteinizing Hormone in Mouse Leydig Tumor Cells.

Mouse Leydig Tumor cells (mLTC), transiently expressing cAMP-dependent luciferase, were used to study the influence of sexual steroids and of adiponectin (ADPN) on the cAMP response to luteinizing hormones (LH). While testosterone and progesterone had no significant effect, several molecules with estrogenic activity (17β-estradiol, ethynylestradiol, and bisphenol A) provoked a decrease in intracellular cyclic AMP accumulation under 0.7 nM human LH stimulation.

Inhibition by fluoxetine of LH-stimulated cyclic AMP synthesis in tumor Leydig cells partly involves AMPK activation.

Fluoxetine (FLX), a widely used antidepressant primarily acting as a selective serotonin reuptake inhibitor (SSRI), has been shown to exhibit other mechanisms of action in various cell types. Consequently, it might have unexpected adverse effects not related to its intended use, possibly in the endocrine regulation of reproduction. We show in the present report that after a 1-hour preincubation of MLTC-1 Leydig cells with FLX, the intracellular cyclic adenosine monophosphate (cAMP) responses to Luteinizing Hormone (LH) and forskolin (FSK) are reduced through AMPK-dependent and -independent pathways respectively.

Solid-Phase Azopeptide Diels-Alder Chemistry for Aza-pipecolyl Residue Synthesis To Study Peptide Conformation.

Solid-phase chemistry for the synthesis and Diels-Alder reaction of Fmoc-protected azopeptides has been developed and used to construct aza-pipecolyl (azaPip) peptides. Considering their ability to induce electronic and structural constraints that favor cis-amide isomer geometry and type VI β-turn conformation in model peptides, azaPip residues have now been introduced into biologically relevant targets by this enabling synthetic method. Turn conformers were shown to be important for receptor affinity, selectivity, and activity by employing azaPip residues to study the conformational requirements of opioid and cluster of differentiation 36 receptor peptide ligands.

Choice of protocol for the in vivo bioassay of equine Chorionic Gonadotropin (eCG / PMSG) in immature female rats.

Equine Chorionic Gonadotropin (eCG) previously known as Pregnant Mare Serum Gonadotropin (PMSG) has been used for decades in regulating reproduction in various domestic animal species. Its use necessitates a good measurement of its bioactivity in commercial preparations. The EUROPEAN PHARMACOPEIA (EP 7.

Equipotent enantiomers of cyclic opioid peptides at μ opioid receptor.

Head-to-tail cyclized analogues of the μ opioid receptor (MOR) agonist tetrapeptides DALDA (H-Tyr-D-Arg-Phe-Lys-NH and [Dmt]DALDA (H-Dmt-D-Arg-Phe-Lys-NH; Dmt = 2',6'-dimethyltyrosine) and their enantiomers (mirror-image isomers) were synthesized and pharmacologically characterized in vitro. Three pairs of enantiomeric cyclic peptides with both mirror-image isomers having equipotent MOR binding affinities but different binding affinities at the δ and κ opioid receptors were identified. The cyclic peptide enantiomers c[-D-Arg-Phe-Lys-Tyr-] () and c[-Arg-D-Phe-D-Lys-D-Tyr-] () showed nearly identical MOR binding affinity (1 - 2 nM) and equipotent MOR antagonist activity.

Comparative Overview of the Mechanisms of Action of Hormones and Endocrine Disruptor Compounds.

Endocrine Disruptor Compounds (EDCs) are synthetic or natural molecules in the environment that promote adverse modifications of endogenous hormone regulation in humans and/or in wildlife animals. In the present paper, we review the potential mechanisms of EDCs and point out the similarities and differences between EDCs and hormones. There was only one mechanism, out of nine identified, in which EDCs acted like hormones (i.

Role of AMPK in mammals reproduction: Specific controls and whole-body energy sensing.

AMP-activated protein kinase (AMPK) is a key enzyme involved in linking the energy sensing to metabolic pathways. As such, it plays a central role at the whole-body level to translate endocrine communications into adapted responses aimed either at saving energy when food is scarce or at allocating it to various functions, particularly reproduction, when food is available. AMPK also plays major roles in the energy individual cells use in order to realize their specific functions.

Main signaling pathways involved in the control of fowl sperm motility.

Motility is an essential function of the mature male gamete and is widely used as an indicator of semen quality. Knowledge of signal transduction pathways regulating sperm motility is therefore important to gain insight into new methods to increase the fertilizing ability of semen samples, especially those subjected to biotechnological processes such as cryopreservation. In this article, we will briefly describe the roles of several signaling pathways involved in the motility of fowl sperm as compared to mammalian sperm.

Characterization of the antinociceptive effects of intrathecal DALDA peptides following bolus intrathecal delivery.

Background and aims We systematically characterized the potency and side effect profile of a series of small opioid peptides with high affinity for the mu opioid receptor. Methods Male Sprague Dawley rats were prepared with intrathecal (IT) catheters, assessed with hind paw thermal escape and evaluated for side effects including Straub tail, truncal rigidity, and pinnae and corneal reflexes. In these studies, DMT-DALDA (dDAL) (H-Dmt-D-Arg-Phe-Lys-NH2 MW=981), dDALc (H-Dmt-Cit-Phe-Lys-NH2 MW=868), dDALcn (H-Dmt-D-Cit-Phe-Nle-NH2 MW=739), TAPP (H-Tyr-D-Ala-Phe-Phe-NH2 MW=659), dDAL-TICP ([Dmt1]DALDA-(CH2)2-NH-TICP[psi]; MW=1519), and dDAL-TIPP (H-Dmt-D-Arg-Phe-Lys(Nε-TIPP)-NH2 were examined.

Strengthening peptide-based drug activity with novel glyconanoparticle.

The therapeutic application of peptide-based drugs is significantly limited by the rapid proteolytic degradation that occurs when in blood. Encapsulation of these peptide structures within a delivery system, such as liposomes, can greatly improve both stability and target delivery. As part of our work focused on novel ambiphilic mannosylated neoglycolipids as targeted drug delivery systems, we have developed a C14-alkyl-mannopyranoside that forms self-assembled monodisperse liposomes.

Impact of 5'-amp-activated Protein Kinase on Male Gonad and Spermatozoa Functions.

As we already know, the male reproductive system requires less energetic investment than the female one. Nevertheless, energy balance is an important feature for spermatozoa production in the testis and for spermatozoa properties after ejaculation. The 5'-AMP-activated protein kinase, AMPK, is a sensor of cell energy, that regulates many metabolic pathways and that has been recently shown to control spermatozoa quality and functions.

A Cyclic Tetrapeptide ("Cyclodal") and Its Mirror-Image Isomer Are Both High-Affinity μ Opioid Receptor Antagonists.

Head-to-tail cyclization of the μ opioid receptor (MOR) agonist [Dmt]DALDA (H-Dmt-d-Arg-Phe-Lys-NH (9; Dmt = 2',6'-dimethyltyrosine) resulted in a highly active, selective MOR antagonist, c[-d-Arg-Phe-Lys-Dmt-] (1) ("cyclodal"), with subnanomolar binding affinity. A docking study of cyclodal using the crystal structure of MOR in the inactive form showed a unique binding mode with the two basic residues of the ligand forming salt bridges with the Asp and Glu receptor residues. Cyclodal showed high plasma stability and was able to cross the blood-brain barrier to reverse morphine-induced, centrally mediated analgesia when given intravenously.