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There is a high demand for agonist biomolecules such as cytokine surrogates in both biological and medicinal research fields. These are typically sourced through natural ligand engineering or affinity-based screening, followed by individual functional validation. However, efficient screening methods for identifying rare hits within immense libraries are very limited. In this research article, we introduce a phenotypic screening method utilizing biological receptor activation-dependent cell survival (BRADS). This method offers a high-throughput, low-background, and cost-effective approach that can be implemented in virtually any biochemical laboratory setting. As a proof-of-concept, we successfully identified a surrogate for human leptin following a two-week cell culture process, without the need for specialized high-throughput equipment or reagents. This surrogate effectively emulates the activity of native human leptin in cell validation assays. Our findings not only underscore the effectiveness of BRADS but also suggest its potential applicability to a broad range of biological receptors, including Notch and GPCRs. [ABSTRACT FROM AUTHOR]

There is a high demand for agonist biomolecules such as cytokine surrogates in both biological and medicinal research fields. These are typically sourced through natural ligand engineering or affinity-based screening, followed by individual functional validation. However, efficient screening methods for identifying rare hits within immense libraries are very limited. In this research article, we introduce a phenotypic screening method utilizing biological receptor activation-dependent cell survival (BRADS). This method offers a high-throughput, low-background, and cost-effective approach that can be implemented in virtually any biochemical laboratory setting. As a proof-of-concept, we successfully identified a surrogate for human leptin following a two-week cell culture process, without the need for specialized high-throughput equipment or reagents. This surrogate effectively emulates the activity of native human leptin in cell validation assays. Our findings not only underscore the effectiveness of BRADS but also suggest its potential applicability to a broad range of biological receptors, including Notch and GPCRs.

Background and Purpose: Glucagon-like peptide-2 (GLP-2) is secreted postprandially from enteroendocrine Lcells and has anabolic action on gut and bone. Short-acting teduglutide is the only approved GLP-2 analog for the treatment of short-bowel syndrome (SBS). To improve the therapeutic effect, we created a series of lipidated GLP-2R agonists. Experimental Approach: Six GLP-2 analogs were studied in vitro for cAMP accumulation, β-arrestin 1 and 2 recruitment, affinity, and internalization. The trophic actions on intestine and bone were examined in vivo in rodents. Key Results: Lipidations at lysines introduced at position 12, 16, and 20 of hGLP-2(1−33) were well-tolerated with less than 2.2-fold impaired potency and full efficacy at the hGLP-2R in cAMP accumulation. In contrast, N- and C-terminal (His1 and Lys30) lipidations impaired potency by 4.2- and 45-fold and lowered efficacy to 77% and 85% of hGLP-2, respectively. All variants were similarly active on the rat and mouse GLP-2Rs and the three most active variants displayed increased selectivity for hGLP-2R over hGLP-1R activation, compared to native hGLP-2. Impact on arrestin recruitment and receptor internalization followed that of Gαs-coupling, except for lipidation in position 20, where internalization was more impaired, suggesting desensitization protection. A highly active variant (C16 at position 20) with low internalization and a half-life of 9.5 h in rats showed improved gut and bone tropism with increased weight of small intestine in mice and decreased CTX levels in rats. Conclusion and implication: We present novel hGLP-2 agonists suitable for in vivo studies of the GLP-2 system to uncover its pharmacological potential.

Glucagon-like-peptide 2 (GLP-2) is an endogenous enteroendocrine physiological trophic peptide. Glepaglutide is a novel long-acting GLP-2 analog under development for the treatment of patients with Short Bowel Syndrome (SBS). The objective of this work was to compare the small intestinal trophic effects in both genders following short (1 week) versus long-term (26-39 weeks) GLP-2 treatment in Wistar rats and Beagle dogs. Following both short- and long-term treatment with glepaglutide, a significant dose-dependent intestinotrophic effect was seen in both genders and species. At all doses increased length and weight of the small intestine as well as macroscopic thickening and villous hypertrophy were noted in all segments of the small intestine, without any differences between genders. The findings were still present following a 6-week recovery period, indicating long-acting intestinotrophic effects of glepaglutide. These studies demonstrate that a long-acting GLP-2 analog (glepaglutide) has a fast onset and long duration of intestinotrophic action with similar profile in both genders and species (rat and dog). [ABSTRACT FROM AUTHOR]

Adiponectin is well established to mediate many beneficial metabolic effects, and this has stimulated great interest in development and validation of adiponectin receptor agonists as pharmaceutical tools. This study investigated the effects of ALY688, a peptide-based adiponectin receptor agonist, in rat L6 skeletal muscle cells. ALY688 significantly increased phosphorylation of several adiponectin downstream effectors, including AMPK, ACC, and p38MAPK, assessed by immunoblotting and immunofluorescence microscopy. Temporal analysis using cells expressing an Akt biosensor demonstrated that ALY688 enhanced insulin sensitivity. This effect was associated with increased insulin-stimulated Akt and IRS-1 phosphorylation. The functional metabolic significance of these signaling effects was examined by measuring glucose uptake in myoblasts stably overexpressing the glucose transporter GLUT4. ALY688 treatment increased basal glucose uptake and enhanced insulin-stimulated glucose uptake. In the model of high-glucose/high-insulin (HGHI)-induced insulin-resistant cells, both temporal studies using the Akt biosensor as well as immunoblotting to assess Akt and IRS-1 phosphorylation indicated that ALY688 significantly reduced insulin resistance. Importantly, we observed that ALY688 administration to high-fat high-sucrose-fed mice also improves glucose handling, validating its efficacy in vivo. In summary, these data indicate that ALY688 activates adiponectin signaling pathways in skeletal muscle, leading to improved insulin sensitivity and beneficial metabolic effects. [ABSTRACT FROM AUTHOR]

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become the most common chronic liver disease worldwide, paralleling the rising pandemic of obesity and type 2 diabetes. Due to the growing global health burden and complex pathogenesis of MASLD, a multifaceted and innovative therapeutic approach is needed. Incretin receptor agonists, which were initially developed for diabetes management, have emerged as promising candidates for MASLD treatment. This review describes the pathophysiological mechanisms and action sites of three major classes of incretin/glucagon receptor agonists: glucagon-like peptide-1 receptor agonists, glucose-dependent insulinotropic polypeptide receptor agonists, and glucagon receptor agonists. Incretins and glucagon directly or indirectly impact various organs, including the liver, brain, pancreas, gastrointestinal tract, and adipose tissue. Thus, these agents significantly improve glycemic control and weight management and mitigate MASLD pathogenesis. Importantly, this study provides a summary of clinical trials analyzing the effectiveness and safety of incretin receptor agonists in MASLD management and provides an in-depth analysis highlighting their beneficial effects on improving liver function, hepatic steatosis, and intrahepatic inflammation. There are emerging challenges associated with the use of these medications in the real world, particularly adverse events, drug-drug interactions, and barriers to access, which are discussed in detail. Additionally, this review highlights the evolving role of incretin receptor agonists in MASLD management and suggests future research directions., Competing Interests: Conflict-of-interest statement: Xie C and Elfeki MA have no conflicts of interest to disclose. Alkhouri N has the following disclosure: Reports grant/research support from 89Bio, Akero, Altimmune, Better Therapeutics, Boehringer Ingelheim, Bristol-Myers Squibb, Corcept, DSM, Galectin, Genentech, Genfit, Gilead, Hepagene, Healio, Intercept, Inventiva, Ionis, Madrigal, Merck, NGM, Noom, NorthSea, Novo Nordisk, Perspectum, Pfizer, Poxel, Viking, and Zydus; Speaker’s fees from AbbVie, Alexion, Echosens, Eisai, Exelixis, Gilead, Intercept, Perspectum, Salix, and Theratechnologies; Consultant for 89Bio, Altimmune, Boehringer Ingelheim, Echosens, Fibronostics, Gilead, Intercept, Madrigal, NorthSea, Novo Nordisk, Perspectum, Pfizer, and Zydus., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Keywords: Glycaemic control; Glucagon-like peptide-1; Receptor agonist; Liraglutide; Semaglutide; Type 2 diabetes EN Glycaemic control Glucagon-like peptide-1 Receptor agonist Liraglutide Semaglutide Type 2 diabetes 515 517 3 11/23/20 20201101 NES 201101 In the recent issue of Diabetes & Metabolism semaglutide and liraglutide are compared head-to-head in previously GLP-1 naïve patients [1]. All patients had formal diabetes education and were specifically coached on the importance of lifestyle modification, specially exercise. 3 2009, 26-34 8 S.P. Marso, S.C. Bain, A. Consoli, F.G. Eliaschewitz, E. Jodar, L.A. Leiter, Semaglutide and cardiovascular outcomes in patients with type 2 diabetes. [Extracted from the article]

The steroid hormone 17β-estradiol (E2) remodels neural circuits at the synaptic level in the mammalian hippocampus and cortex. However, the underlying mechanism of synapse dynamics remains unclear. To elucidate the mechanism, we traced individual dendritic spines on layer V pyramidal neurons of the primary sensory cortex in adult female mice under E2 intervention using two-photon in vivo imaging microscopy. We confirmed the increase of the spine density upon E2 treatment in the intact mouse cortex. Furthermore, we found that this increase is due to the promotion of spine formation and the stability of newly formed spines. E2 treatment doesn’t alter the elimination rate of pre-existing spines. Our results also indicate that the activation of the estrogen receptor β (ERβ) mimics the effects of E2 administration on spine dynamics. Taken together, our findings suggest that estrogen promotes growth and stability of new dendritic spines via the ERβ pathway in the intact cortex of female mice. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-2 (GLP-2) is secreted postprandially from enteroendocrine L cells and has anabolic action on gut and bone. Short-acting teduglutide is the only approved GLP-2 analog for the treatment of short-bowel syndrome (SBS). To improve the therapeutic effect, we created a series of lipidated GLP-2R agonists. Six GLP-2 analogs were studied in vitro for cAMP accumulation, β-arrestin 1 and 2 recruitment, affinity, and internalization. The trophic actions on intestine and bone were examined in vivo in rodents. Lipidations at lysines introduced at position 12, 16, and 20 of hGLP-2(1−33) were well-tolerated with less than 2.2-fold impaired potency and full efficacy at the hGLP-2R in cAMP accumulation. In contrast, N- and C-terminal (His1 and Lys30) lipidations impaired potency by 4.2- and 45-fold and lowered efficacy to 77% and 85% of hGLP-2, respectively. All variants were similarly active on the rat and mouse GLP-2Rs and the three most active variants displayed increased selectivity for hGLP-2R over hGLP-1R activation, compared to native hGLP-2. Impact on arrestin recruitment and receptor internalization followed that of Gαs-coupling, except for lipidation in position 20, where internalization was more impaired, suggesting desensitization protection. A highly active variant (C16 at position 20) with low internalization and a half-life of 9.5 h in rats showed improved gut and bone tropism with increased weight of small intestine in mice and decreased CTX levels in rats. We present novel hGLP-2 agonists suitable for in vivo studies of the GLP-2 system to uncover its pharmacological potential. [Display omitted] • Lipidation of GLP-2 is best carried out in the middle part of the peptide backbone. • Lipidation of GLP-2 prolongs the half-life beyond that obtained from other approaches. • Long-acting GLP-2 analog with high activity across the human, rat and mouse GLP-2R. • Lipidation of GLP-2 at position 20 protects against receptor desensitization. • Improved gut and bone tropic actions in rodents administrated with long-acting GLP-2. [ABSTRACT FROM AUTHOR]

Covalent modifications of titanium with small molecules known to promote human osteoblast maturation are especially attractive in developing superior biomaterials. An important step in securing competent bone formation at implant sites is promoting the formation of mature osteoblasts, either from committed pre-osteoblasts or from their mesenchymal progenitors. To this end our research has focussed on identifying molecules that enhance human osteoblast formation and maturation and to develop ways of covalently attaching these molecules to implant surfaces so that they are more likely to withstand the rigors of the implantation process whilst still retaining their bioactivity. Herein we report the novel production of lipid-functionalised titanium using lysophosphatidic acid or a related compound, (3S) 1-fluoro-3-hydroxy-4-butyl-1-phosphonate. Both lipids were especially effective at co-operating with calcitriol to promote human osteoblast maturation at these modified Ti surfaces in vitro. The novel findings presented offer enticing new developments towards the fabrication of next-generation implant devices with the potential to significantly enhance the osseointegration process and with it improvements in future prosthesis performance and longevity.

Signaling by single-pass transmembrane receptors often involves a formation of ligand-induced receptor dimers with particular conformation, and bivalent receptor binders can modulate receptor functions by inducing different receptor dimer conformations, although such agents are difficult to design. Here, we describe the generation of both antagonistic and agonistic receptor dimerizers toward PlexinB1 (PlxnB1), a receptor for semaphorin 4D (Sema4D), by grafting two different PlxnB1-binding peptides onto the human immunoglobulin G1 (IgG1) Fc protein. The function-modulating activity of a peptide Fc was strongly dependent on the type of the peptide as well as the grafting site, with the best variants showing activity at an nM concentration range. Structural analysis of each peptide-PlxnB1 complex revealed that the agonistic Fc dimerizes PlxnB1 in a face-to-face fashion similar to that induced by Sema4D, whereas antagonistic Fc would induce signaling-incompetent PlxnB1 dimer conformation, enforcing the idea that plexin activation is primarily controlled by the receptor orientation within the dimer. [Display omitted] • PlexinB1-binding activity of two macrocyclic peptides can be grafted onto Fc protein • Peptide-grafted Fc variably modulates PlexinB1 function by differently dimerizing it • The agonistic Fc activates PlexinB1 like the physiological ligand semaphorin 4D • The antagonistic Fc reverses the cell collapse response induced by semaphorin 4D PlexinB1 is a signaling receptor implicated in bone homeostasis and cancer. Nakamura-Sugano et al. developed artificial receptor dimerizers by grafting PlexinB1-binding peptides onto Fc protein, which variably modulate receptor functions on cells. Structural analyses of the peptide-PlexinB1 complexes revealed that a particular dimeric configuration of PlexinB1 is required for signaling. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) are injectable glucose-lowering medications approved for the treatment of adult patients with type 2 diabetes mellitus (T2DM). This article provides practical information to guide primary care physicians on the use of GLP-1RAs in patients with T2DM. Two short-acting (once- or twice-daily administration; exenatide and liraglutide) and three long-acting (weekly administration; albiglutide, dulaglutide and exenatide) GLP-1RAs are currently approved in the US. These drugs provide levels of GLP-1 receptor agonism many times that of endogenous GLP-1. The GLP-1RAs have been shown to significantly improve glycemic parameters and reduce body weight. These agents work by activating GLP-1 receptors in the pancreas, which leads to enhanced insulin release and reduced glucagon release—responses that are both glucose-dependent—with a consequent low risk for hypoglycemia. Effects on GLP-1 receptors in the CNS and the gastrointestinal tract cause reduced appetite and delayed glucose absorption due to slower gastric emptying. The most common adverse effects are gastrointestinal, which are transient and less common with the long-acting drugs. GLP-1RAs are recommended as second-line therapy in combination with metformin, sulfonylureas, thiazolidinediones or basal insulin, providing a means of enhancing glucose control while offsetting the weight gain associated with insulin and some oral agents. GLP-1RAs represent a useful tool that the primary care physician can use to help patients with T2DM achieve their therapeutic goals. [ABSTRACT FROM PUBLISHER]

Hepatocyte growth factor (HGF), through activation of the c‐MET receptor, mediates biological processes critical for tissue regeneration; however, its clinical application is limited by protein instability and poor recombinant expression. We previously engineered an HGF fragment (eNK1) that possesses increased stability and expression yield and developed a c‐MET agonist by coupling eNK1 through an introduced cysteine residue. Here, we further characterize this eNK1 dimer and show it elicits significantly greater c‐MET activation, cell migration, and proliferation than the eNK1 monomer. The efficacy of the eNK1 dimer was similar to HGF, suggesting its promise as a c‐MET agonist.HGF is difficult to produce and unstable, highlighting a need for c‐MET agonists. A disulfide‐linked dimer (eNK1 dimer) was created from an engineered HGF fragment. The eNK1 monomer is a weak agonist and only activates c‐MET at high concentrations. The eNK1 dimer is a potent activator of c‐MET, cell migration, and proliferation. The eNK1 dimer elicits similar biological activity compared to HGF. [ABSTRACT FROM AUTHOR]

Background: Estrogen receptor (ER) β acts as a tumor suppressor in malignant mesotheliomas. Methods: Here we explored the anti-proliferative and anti-tumorigenic efficacy of the selective ERβ agonist, KB9520, in human mesothelioma cell lines in vitro and in a mesothelioma mouse model in vivo. Results: KB9520 showed significant anti-proliferative effect in ERβ positive human malignant pleural mesothelioma cells in vitro. Selective activation of ERβ with KB9520 sensitized the cells to treatment with cisplatin, resulting in enhanced growth inhibition and increased apoptosis. Furthermore, in CD1 nude mice mesothelioma tumor growth was significantly inhibited when KB9520 was added on top of the standard of care chemo combination cisplatin/ pemetrexed, as compared to the cisplatin/pemetrexed alone group. Importantly, KB9520 exerted a protective effect to cisplatin toxicity in the non-malignant mesothelium derived MET5A cells. Conclusions: Together, the data presented suggest that selective targeting of ERβ may be an efficacious stand-alone treatment option and/or become an important add-on to existing malignant mesothelioma therapy. [ABSTRACT FROM AUTHOR]

Chronic constipation (CC) is a highly prevalent heterogeneous disorder. Although CC is not known to be associated with the development of serious disease or with excess mortality, it considerably reduces the patients quality of life. In addition, it represents an economic burden to patients and society. The majority of patients with CC successfully manage the disorder by dietary management and the use of laxatives. Patients with functional CC (slow-transit and non-slow transit constipation) do not respond to laxatives and are a small fraction of the total population complaining of constipation. Regardless of the low number of these patients, the intractability of their symptoms causes psychological and social stress and greatly impairs their quality of life. Furthermore, these patients consume a disproportionate quantity of medical resources. It appears that these patients have a disturbance in the serotonin transmission system, which results in a cascade of alterations in a number of gut neuroendocrine hormones/transmitters. The effect of prucalopride, a serotonin receptor agonist, in this category of patients appears to be not only a pharmacological prokinetic action, but also a correction of a pre existing disturbance. Linaclotide, a member of the guanylin peptide family, binds to the ligand binding region of guanylate cyclase-C on the luminal surface of gastrointestinal epithelia resulting in increased fluid secretion. This drug has also been found to be effective for the treatment of functional CC. In addition, biofeedback and sacral nerve stimulation are effective in the treatment of CC caused by pelvic floor disorders. [ABSTRACT FROM AUTHOR]

Abstract: Altered glutamatergic synaptic transmission is among the key events defining the course of Alzheimer''s disease (AD). mGlu2 receptors, a subtype of group II metabotropic glutamate receptors, regulate (as autoreceptors) fast synaptic transmission in the CNS via the controlled release of the excitatory amino acid glutamate. Since their pharmacological manipulation in rodents has been reported to affect cognition, they are potential drug targets for AD therapy. We examined the fate of these receptors in cases of AD as well as in aging PS2APP mice—a proposed model of the disease. In vitro binding of [3H]LY354740, a selective group II agonist (with selective affinity for mGlu2 receptors, under the assay conditions used) and quantitative radioautography revealed a partial, but highly significant, loss of receptors in amyloid-affected discrete brain regions of AD cases and PS2APP mice. Among the mouse brain regions affected were, above all, the subiculum but also frontolateral cortex, dentate gyrus, lacunosum moleculare and caudate putamen. In AD, significant receptor losses were registered in entorhinal cortex and lacunosum moleculare (40% and 35%, respectively). These findings have implications for the development of selective ligands for symptomatic therapy in AD and for its diagnosis. [Copyright &y& Elsevier]

Abstract: We characterized the pharmacological properties of P2 receptors expressed in G292 osteoblastic cells by studying the responses or changes in intracellular Ca2+ level to P2 receptor agonists, antagonists and modulators. ATP induced robust responses in a concentration-dependent manner with EC50 of 0.5±0.07 μM. While α,β-methylene-ATP (αβmeATP) and 2'',3''-O-(4-benzoylbenzoyl)-ATP (BzATP) were ineffective, ADP mimicked the action of ATP with EC50 of 0.7±0.2 μM. UTP and UDP also evoked responses with EC50 of 2.0±0.4 μM and 0.5±0.1 μM respectively, but their responses were much smaller, resulting in an order of the response magnitude: ATP~ADP>>UTP~UDP. The responses evoked by ATP and ADP were blocked by pyridoxal-5''-phosphate-6-azophenyl-2,4,-disulfonate (PPADS) with IC50 of 3.0±0.05 μM and 5.0±0.4 μM respectively, but not by suramin up to 30 μM. ATP-evoked responses were insensitive to inhibition by trinitrophenyl-ATP (TNP-ATP) and brilliant blue G. ADP-evoked responses were significantly inhibited by 2''-deoxy-N 6-methyladenosine-3'',5''-biphosphate (MRS2179) and 2-chloro-N 6-methyl-(N)-methanocarba-2''-deoxyadenosine-3'',5''-bisphosphate (MRS2279) with IC50 of 48±1.9 μM and 7.7±0.9 μM respectively. Taken together, these results provide strong evidence for functional expression of ATP-sensitive P2Y receptors and particularly P2Y1-like receptor in G292 cells. [Copyright &y& Elsevier]

Synthetic agonists of peroxisome proliferator-activated receptor (PPAR)-δ have shown a promising pharmacological profile in preclinical models of metabolic and cardiovascular disease. At present, the pharmaceutical development of these drugs exploits the potential to raise plasma HDL-cholesterol in animals and their insulin-sensitising and glucose-lowering properties. PPAR-δ agonists have also proven to be powerful research tools that have provided insights into the role of fatty acid metabolism in human physiology and disease. Activation of PPAR-δ induces the expression of genes important for cellular fatty acid combustion and an associated increase in whole-body lipid dissipation. The predominant target tissue in this regard is skeletal muscle, in which PPAR-δ activation regulates the oxidative capacity of the mitochondrial apparatus, switches fuel preference from glucose to fatty acids, and reduces triacylglycerol storage. These changes counter the characteristic derangements of insulin- resistant skeletal muscle but resemble the metabolic adaptation to regular physical exercise. Apart from effects on fuel turnover, there is evidence for direct antiatherogenic properties, because PPAR-δ activation increases cholesterol export and represses inflammatory gene expression in macrophages and atherosclerotic lesions. Whereas conclusions about the full potential of PPAR-δ as a drug target await the result of large scale clinical testing, ongoing investigation of this nuclear receptor has greatly improved our knowledge of the physiological regulation of whole-body fuel turnover and the interdependence of mitochondrial function and insulin sensitivity. [ABSTRACT FROM AUTHOR]

Abstract: A novel benzimidazole series of small-molecule thrombopoietin receptor agonists has been discovered. Herein, we discuss the preliminary exploration of structure–activity relationships within this chemotype. [Copyright &y& Elsevier]

Over the last 10 years, structural studies of the ligand-binding domains of nuclear hormone receptors have provided a wealth of information on the nature of ligand-binding and its role in receptor activation. This review examines the insights that studies on oestrogen receptor subtypes ERα and ERβ have provided in terms of (1) basis of receptor activation; (2) recruitment of coregulators; (3) hormone recognition; and (4) subtype-selective ligands. It also highlights the implications for the binding of endocrine disruptors. [Copyright &y& Elsevier]