GPR119 Agonists Research Articles

Design and Synthesis of Novel GPR139 Agonists with Therapeutic Effects in Mouse Models of Social Interaction and Cognitive Impairment.

The GPR139 receptor is an orphan G-protein-coupled receptor (GPCR) mainly found in the central nervous system and is a potential therapeutic target for the treatment of schizophrenia and drug addiction. Guided by the reported structure of GPR139, we conducted medicinal chemistry optimizations of TAK-041, the GPR139 agonist in clinical trials. New compounds with three different core structures were designed and synthesized, and their activity at GPR139 was evaluated. Among them, compounds 15a (EC50 = 31.4 nM) and 20a (EC50 = 24.7 nM) showed potent agonist activity at GPR139 and good pharmacokinetic properties. In murine schizophrenia models, both compounds rescued the social interaction deficits observed in BALB/c mice. Compound 20a also alleviated cognitive deficits in mice with a pharmacologically induced model of schizophrenia. These findings further demonstrated the potential of GPR139 agonists in alleviating the negative symptoms and cognitive deficits of schizophrenia. Compound 20a is worth further evaluation as an antischizophrenia drug candidate.

Discovery and Characterization of Novel CNS-Penetrant GPR55 Agonists.

From our NETSseq-derived human brain transcriptomics data, we identified GPR55 as a potential molecular target for the treatment of motor symptoms in patients with Parkinson's disease. From a high-throughput screen, we identified and optimized agonists with nanomolar potency against both human and rat GPR55. We discovered compounds with either strong or limited β-arrestin signaling and receptor desensitization, indicating biased signaling. A compound that showed minimal GPR55 desensitization demonstrated a reduction in firing frequency of medium spiny neurons cultured from rat striatum but did not reverse motor deficits in a rat hypolocomotion model. Further profiling of several desensitizing and non-desensitizing lead compounds showed that they are selective over related cannabinoid receptors CB1 and CB2 and that unbound brain concentrations well above the respective GPR55 EC50 can be readily achieved following oral administration. The novel brain-penetrant GPR55 agonists disclosed can be used to probe the role of this receptor in the brain.

Chronic memantine disrupts spatial memory and up-regulates Htr1a gene expression in the hippocampus of GPR39 (zinc-sensing receptor) KO male mice

GPR39 is a receptor involved in zincergic neurotransmission, and its role in regulating psychological functions is an active area of research. The purported roles of GPR39 at the cellular level include regulation of inflammatory and oxidative stress response, and modulation of GABAergic and endocannabinoid neurotransmission. GPR39 knock-out (KO) mice exhibit episodic-like and spatial memory (ELM and SM, respectively) deficits throughout their lifetime, and are similar in that respect to senescent wild-type (WT) conspecifics. Since a role for zinc has been postulated in neurodegenerative disorders, in this study we investigated the possibility of a pharmacological rescue of both types of declarative memory with memantine - a noncompetitive NMDAR antagonist used for slowing down dementia; or, a putative GPR39 agonist – TC-G 1008.First, we tested adult WT and GPR39KO male mice under acute 5 mg/kg memantine or vehicle treatment in an object recognition task designed to simultaneously probe the “what?”, “where?” and “when?” components of ELM. Next, we investigated the impact of chronic memantine or TC-G 1008 on ELM and SM (Morris water maze, MWM) in both WT and GPR39KO mice. Following chronic experiments, we assessed with qRT-PCR hippocampal gene expression of targets previously associated with GPR39.We report: no effects of acute memantine on ELM; a tendency to improve the “where?” component of ELM in both WT and GPR39 KO mice following 12 days of memantine; and, a disruption of SM in GPR39KO mice after 24 days of memantine treatment. The latter result was associated with upregulation of Htr1a hippocampal expression.

Restoring prefrontal cortical excitation-inhibition balance with cannabidiol ameliorates neurobehavioral abnormalities in a mouse model of neurodevelopmental disorders

Maternal immune activation (MIA) resulting from viral infections during pregnancy is linked to increased rates of neurodevelopmental disorders in offspring. However, the mechanisms underlying MIA-induced neurobehavioral abnormalities remain unclear. Here, we used a poly (I:C)-induced MIA mouse model to demonstrate the presence of multiple behavioral deficits in male offspring. Through RNA sequencing (RNA-seq), we identified significant upregulation of genes involved in axonogenesis, synaptogenesis, and glutamatergic synaptic neurotransmission in the mPFC of MIA mice. Electrophysiological analyses further revealed an excitatory-inhibitory (E/I) synaptic imbalance in mPFC pyramidal neurons, leading to hyperactivity in this brain region. Cannabidiol (CBD) effectively alleviated the behavioral abnormalities observed in MIA offspring by reducing glutamatergic transmission and enhancing GABAergic neurotransmission of mPFC pyramidal neurons. Activation of GPR55 by lipid lysophosphatidylinositol (LPI), an endogenous GPR55 agonist, specifically in the mPFC of healthy animals led to MIA-associated behavioral phenotypes, which CBD could effectively reverse. Moreover, we found that a GPR55 antagonist can mimic CBD's beneficial effects, indicating that CBD's therapeutic effects are mediated via the LPI-GPR55 signaling pathway. Therefore, we identified mPFC as a primary node of a neural network that mediates MIA-induced behavioral abnormalities in offspring. Our work provides insights into the mechanisms underlying the developmental consequences of MIA and identifies CBD as a promising therapeutic approach to alleviate these effects.

G protein-coupled receptor 55 activated by palmitoylethanolamide is associated with the development of nocturia associated with circadian rhythm disorders

AimsBladder function is regulated by clock genes and dysregulation of circadian bladder function can cause nocturia. The blood concentration of palmitoylethanolamide (PEA), a fatty acid metabolite, changes with circadian rhythm. Clock gene abnormalities demonstrate the highest PEA levels during the sleep phase. PEA is a GPR55 agonist that influences urination; therefore, increased PEA during the sleep phase may cause nocturia. Herein, we investigated the function of GPR55 to evaluate the relationship between GPR55 and nocturia that evoked higher PEA during the sleep phase in patients with circadian rhythm disorders. Main methodsMale C57BL/6 mice were used. GPR55 localization was evaluated by immunofluorescence staining, qRT-PCR, and western blotting. Variations in PEA-induced intracellular Ca2+ concentrations were measured in primary cultured mouse urothelial cells (UCs) using Ca2+ imaging. PEA-induced NGF and PGI2 release in UCs was measured by ELISA. The micturition reflex pathway after PEA administration was evaluated using immunofluorescence staining. Key findingsGPR55 was predominant in the UC layer. PEA induced release of Ca2+ from the endoplasmic reticulum into the UC cytoplasm. ELISA and immunofluorescence staining revealed that NGF and PGI2 were released from bladder UCs, stimulated the pontine micturition center in mice, and induced nocturia. SignificanceThe loss of regular circadian metabolizing rhythm in fatty acids causes higher blood PEA levels during the sleep phase. Binding of PEA to GPR55 in UC may activate the downstream processes of the micturition reflex, leading to nocturia. These findings suggest a new mechanism for nocturia and its potential as a therapeutic target.

GPR119 activation by DA-1241 alleviates hepatic and systemic inflammation in MASH mice through inhibition of NFκB signaling

GPR119 activation has been suggested to improve hyperglycemia, dyslipidemia and hepatic steatosis. But its therapeutic potential for metabolic dysfunction-associated steatohepatitis (MASH) are underexplored. Here, we investigated the effects of DA-1241, a novel GPR119 agonist, on MASH and explored its underlying mechanism of anti-inflammatory effects. The in vivo anti-MASH effect was assessed by examining the preventive effect in MS-MASH and Ob-MASH mice and the therapeutic effect in MASH with severe hyperglycemia and diet-induced obese (DIO)-MASH mice. Histological and biochemical changes in liver tissue were assessed. Both plasma and hepatic biomarkers related to inflammation and fibrosis were comprehensively analyzed. To understand its mode of action, changes in NFκB signaling were determined in HepG2 and THP-1 cells. DA-1241 attenuated MASH progression and alleviated the MASH phenotypes in MASH mouse models with different etiologies, regardless of glucose-lowering activity. In DIO-MASH mice, DA-1241 significantly reduced biochemical parameters related to steatosis, inflammation and fibrosis in the liver with reduced plasma liver enzymes. When used in combination with a dipeptidyl peptidase 4 (DPP4) inhibitor, DA-1241 further improved the MASH phenotype by increasing endogenous glucagon-like peptide-1 effect. Notably, DA-1241 alone and in combination reduced liver inflammation and restored inflammation-related hepatic gene expression, leading to remission of systemic inflammation as assessed by plasma inflammatory cytokines and chemokines. We demonstrated that DA-1241 reduces macrophage differentiation through downregulation of NFκB signaling by activating GPR119. Our data suggest the therapeutic potential of DA-1241, alone and in combination with a DPP4 inhibitor, for MASH.

DHA-Provoked Reduction in Adipogenesis and Glucose Uptake Could Be Mediated by Gps2 Upregulation in Immature 3T3-L1 Cells.

The signaling pathway of fatty acids in the context of obesity is an extensively explored topic, yet their primary mechanism of action remains incompletely understood. This study aims to examine the effect of docosahexaenoic acid (DHA) on some crucial aspects of adipogenesis in differentiating 3T3-L1 cells, using palmitic acid-treated (PA), standard differentiated, and undifferentiated adipocytes as controls. Employing 60 µM DHA or PA, 3T3-L1 preadipocytes were treated from the onset of adipogenesis, with negative and positive controls included. After eight days, we performed microscopic observations, cell viability assays, the determination of adiponectin concentration, intracellular lipid accumulation, and gene expression analysis. Our findings demonstrated that DHA inhibits adipogenesis, lipolysis, and glucose uptake by suppressing peroxisome proliferator-activated receptor gamma (Pparg) and G-protein coupled receptor 120 (Gpr120) gene expression. Cell cytotoxicity was ruled out as a causative factor, and β-oxidation involvement was suspected. These results challenge the conventional belief that omega-3 fatty acids, acting as Pparg and Gpr120 agonists, promote adipogenesis and enhance insulin-dependent glucose cell flux. Moreover, we propose a novel hypothesis suggesting the key role of the co-repressor G protein pathway suppressor 2 in mediating this process. Additional investigations are required to elucidate the molecular mechanisms driving DHA's anti-adipogenic effect and its broader health implications.

Oral administration of linoleic acid immediately before glucose load ameliorates postprandial hyperglycemia.

Introduction: Fatty acids are a major nutrient in dietary fat, some of which are ligands of long-chain fatty acid receptors, including G-protein-coupled receptor (GPR) 40 and GPR120. Pretreatment with GPR40 agonists enhanced the secretion of insulin in response to elevating blood glucose levels after glucose load in a diabetes model, but pretreatment with GPR120 agonist did not ameliorate postprandial hyperglycemia. This study examined whether oral administration of linoleic acid (LA), a GPR40 and GPR120 agonist, immediately before glucose load would affect the elevation of postprandial blood glucose levels in rats. Methods: Male rats and rats with type 1 diabetes administered streptozocin were orally administered LA, trilinolein, α-linolenic acid (α-LA), oleic acid, TAK-875, or TUG-891 immediately before glucose load. Blood glucose levels were measured before, then 15, 30, 60 and 120min after glucose load. CACO-2 cells were used to measure the uptake of [14C] α-MDG for 30min with or without LA. Gastric content from rats administered LA was collected 15 and 30min after glucose load, and blood samples were collected for measurement of glucagon-like peptide 1 (GLP-1) and cholecystokinin concentrations. Results: The elevation of postprandial blood glucose levels was slowed by LA but not by trilinolein in rats without promotion of insulin secretion, and this effect was also observed in rats with type 1 diabetes. The uptake of α-MDG, an SGLT-specific substrate, was, however, not inhibited by LA. Gastric emptying was slowed by LA 15min after glucose load, and GLP-1, but not cholecystokinin, level was elevated by LA 15min after glucose load. TUG-891, a GPR120 agonist, ameliorated postprandial hyperglycemia but TAK-875, a GPR40 agonist, did not. Pretreatment with AH7614, a GPR120 antagonist, partially canceled the improvement of postprandial hyperglycemia induced by LA. α-LA, which has high affinity with GPR120 as well as LA, slowed the elevation of postprandial blood glucose levels, but oleic acid, which has lower affinity with GPR120 than LA, did not. Conclusion: Oral administration of LA immediately after glucose load ameliorated postprandial hyperglycemia due to slowing of gastric emptying via promotion of GLP-1 secretion. The mechanisms may be associated with GPR120 pathway.

6-LB: GPR119 Agonist PRM A Increases Glucagon Response to Hypoglycemia in Rats

Glucagon (Gcg) is crucial in the counter-regulatory response (CRR) to hypoglycemia yet this is severely impaired in T1D. This pathophysiology was recognized 50 years ago, but only recently have drug targets emerged to amplify Gcg CRR in T1D. One promising target is the receptor GPR119, expressed in gut endocrine cells and pancreatic islets with highest expression on α-cells, 10-fold greater than on β-cells. In the current study, a GPR119 agonist (PRM A) was given by oral gavage at doses of 3, 10 and 30 mg per kg (mpk), to rats (Sprague-Dawley, groups of 8) two hours prior to induction of hypoglycemia by an insulin tolerance test (ITT), using a dose of 1.25 Units per kg, given by intra-peritoneal injection at t=0 min. A vehicle-treated (V) control and a positive comparator group, given the GPR119 agonist MBX-2982 (10 mpk) were also studied. MBX-2982 is currently being used in a clinical trial to assess its effect on Gcg CRR in volunteers with T1D challenged with a hypoglycemic clamp. In rats in the current study, severe hypoglycemia was induced during the ITT; blood glucose nadir was achieved by 60 min in association with peak insulin ≥ 100 µU/ml. Glucose and insulin were similar across groups. The healthy V rats mounted a normal Gcg CRR, with a peak value of 26±10 pM, 5-fold above baseline. Pre-treatment with PRM A significantly amplified Gcg CRR relative to V (to 86±17, 79±18, and 85±12 pM; at 3, 10, and 30 mpk; p<0.0001 vs V). The Gcg AUC during the ITT was nearly 50% greater with all doses of PRM A (p<0.05 vs V) and the peak Gcg CRR was shifted earlier (p<0.01 vs V). MBX-2982 pre-treated rats, relative to V, trended to a higher peak (49±14 vs 26±10 pM) and AUC Gcg (7292±2039 vs 6855±1306 pM*h), but neither difference was significant, whereas the differences for PRM A were strongly significant for time and treatment. In summary, PRM A, a potent GPR119 agonist, tripled peak Gcg CRR during an ITT in healthy rats, affirming that the target of GPR119 holds promise as a novel means to mitigate the dangerous risk of hypoglycemia for individuals with T1D. Disclosure D. W. K. Kwok: None. D. Alexander: None. N. R. A. Beeley: None. D. Kelley: Consultant; Pramana Pharmaceuticals, Inc, Kallyope. Funding Pramana Pharmaceuticals Inc.

Discovery of orally active sulfonylphenyl thieno[3,2-d]pyrimidine derivatives as GPR119 agonists

G-protein-coupled receptor 119 (GPR119) has great potential as a therapeutic target for the treatment of type II diabetes. Novel thieno[3,2-d]pyrimidine derivatives were discovered as GPR119 agonists through a bioisosteric replacement strategy. The sulfonylphenyl thieno[3,2-d] pyrimidine scaffold was introduced, and its derivatives exhibited potent agonistic activity for GPR119 in cell-based assays. The representative derivative 43 displayed excellent pharmacokinetic profiles in rodents and significantly improved glucose tolerance in vivo. In OGTT study, compound 43 reduced significantly blood glucose levels in both mice and rats.

First GPR119 PET Imaging Ligand: Synthesis, Radiochemistry, and Preliminary Evaluations.

G-protein-coupled receptor 119 (GPR119) has emerged as a promising target for treating type 2 diabetes mellitus. Activating GPR119 improves glucose homeostasis, while suppressing appetite and weight gain. Measuring GPR119 levels in vivo could significantly advance GPR119-based drug development strategies including target engagement, occupancy, and distribution studies. To date, no positron emission tomography (PET) ligands are available to image GPR119. In this paper, we report the synthesis, radiolabeling, and preliminary biological evaluations of a novel PET radiotracer [18F]KSS3 to image GPR119. PET imaging will provide information on GPR119 changes with diabetic glycemic loads and the efficacy of GPR119 agonists as antidiabetic drugs. Our results demonstrate [18F]KSS3's high radiochemical purity, specific activity, cellular uptake, and in vivo and ex vivo uptake in pancreas, liver, and gut regions, with high GPR119 expression. Cell pretreatment with nonradioactive KSS3, rodent PET imaging, biodistribution, and autoradiography studies showed significant blocking in the pancreas showing [18F]KSS3's high specificity.

Preliminary biological evaluations of first brain‐penetrant GPR119‐based radiotracer in rodents and non‐human primates

AbstractBackgroundG‐protein‐coupled receptors (GPCRs) plays a key role in regulating glucose metabolism. While GPR119 (an important GPCR) agonists have shown potential for improving neurologic and cognitive function in patients with AD and type2 diabetes mellitus (T2DM), clinical interventions targeting GPR119 will require accurate in vivo measures such as PET imaging. We recently synthesized a series of novel piperdine analogs, identifying two analogs (T1 and T2) with high GPR119 binding potency (2‐5 nM) for PET radiochemistry. Here we report their radiochemistry and initial biological evaluations in neuronal cells, normal rodents, and monkeys (vervets).Method[18F]T1/T2 radiochemistry was performed in TRASIS‐AIO automated module following [18F]¯‐based nucleophilic substitution of corresponding precursors. [18F]T1 and T2 in vitro assays were performed in three patient‐derived cell lines with different GPR119 expression (MDM‐MD‐231<NCI‐H1716<HepG2), with and without GPR119 agonists and non‐radioactive T1/T2. Dynamic 0‐60 min brain microPET/CT imaging and biodistribution were performed in normal balb/c mice (n = 4). Healthy adult female vervets (n = 6, 4.5‐6.7 kg) underwent 0‐90 min brain PET imaging. Standard uptake value (SUVmax) and time‐activity curves (TACs) were calculated for whole brain PET/MR images.ResultBoth [18F]T1 and T2 were produced in high radiochemical purities (>98%) and specific activities (∼3800‐4500 mCi/µmol), decay corrected to end of synthesis. Radioactive cell uptake was lower in MDM‐MD‐231 cells (lowest GPR119 expression) and higher in HepG2 cells (higher GPR119 expression); uptake also significantly increased with GPR119 agonists and T1/T2 treatments compared to baseline. [18F]T2 showed slightly better brain uptake in mice compared to [18F]T1 (SUVmax = 0.35±0.07 Vs. 0.55±0.09 g/mL). Biodistribution of [18F]T2 (%ID/mg = 1.01±0.09) also showed high brain uptake. SUVmax (avg = 2.6±0.1 g/mL) and TACs of both [18F]T1 and [18F]T2 in monkey brains demonstrated rapid distribution across BBB within 10 min and favorable clearance within 90 min of tracer injection (Fig 1).ConclusionRadiochemistry was successfully automated and optimized. Cell uptake showed direct relationships between radiotracer uptake and GPR119 expression. MicroPET imaging, biodistribution in rodents and monkey PET imaging demonstrated excellent brain uptake and favorable pharmacokinetics, indicating BBB penetration. These data suggest for the first time that [18F]T1 and T2 have potential for imaging GPR119 in brains of humans with AD or T2DM.

Photosynthetic Fixation of CO2 in Alkenes by Heterogeneous Photoredox Catalysis with Visible Light

AbstractLight‐driven fixation of CO2 in organics has emerged as an appealing alternative for the synthesis of value‐added fine chemicals. Challenges remain in the transformation of CO2 as well as product selectivity due to its thermodynamic stability and kinetic inertness. Here we develop a boron carbonitride (BCN) with the abundant terminal B/N defects around the mesoporous walls, which essentially enhances surface active sites as well as charge transfer kinetics, boosting the overall rate of CO2 adsorption and activation. In this protocol, anti‐Markovnikov hydrocarboxylation of alkenes with CO2 to an extended carbon chain is achieved with good functional group tolerance and specific regioselectivity under visible‐light irradiation. The mechanistic studies demonstrate the formation of CO2 radical anion intermediate on defective boron carbonitride, leading to the anti‐Markovnikov carboxylation. Gram‐scale reaction, late‐stage carboxylation of natural products and synthesis of anti‐diabetic GPR40 agonists reveal the utility of this method. This study sheds new insight on the design and application of metal‐free semiconductors for the conversion of CO2 in an atom‐economic and sustainable manner.

Photosynthetic Fixation of CO2 in Alkenes by Heterogeneous Photoredox Catalysis with Visible Light.

Light-driven fixation of CO2 in organics has emerged as an appealing alternative for the synthesis of value-added fine chemicals. Challenges remain in the transformation of CO2 as well as product selectivity due to its thermodynamic stability and kinetic inertness. Here we develop a boron carbonitride (BCN) with the abundant terminal B/N defects around the mesoporous walls, which essentially enhances surface active sites as well as charge transfer kinetics, boosting the overall rate of CO2 adsorption and activation. In this protocol, anti-Markovnikov hydrocarboxylation of alkenes with CO2 to an extended carbon chain is achieved with good functional group tolerance and specific regioselectivity under visible-light irradiation. The mechanistic studies demonstrate the formation of CO2 radical anion intermediate on defective boron carbonitride, leading to the anti-Markovnikov carboxylation. Gram-scale reaction, late-stage carboxylation of natural products and synthesis of anti-diabetic GPR40 agonists reveal the utility of this method. This study sheds new insight on the design and application of metal-free semiconductors for the conversion of CO2 in an atom-economic and sustainable manner.

Piperidinium borate catalyzed Knoevenagel condensation of carbonyl compounds with active methylenes

A piperidinium borate, an organic conjugate base as a catalyst under mild conditions, effectively promotes Knoevenagel condensation between aromatic, heterocyclic, α, β unsaturated aldehydes and aliphatic, cyclic ketones with active methylenes. Piperidinium borate can be easily prepared from widely available boric acid and piperidine. The present method showed the advantages of mild reaction conditions, wide and easy availability of starting materials, and higher product yields. In addition, all the products were separated simply by filtering and washing with water. The intermediate of AMG 837, a new GPR40 agonist, was synthesized using the similar reaction conditions used in this protocol. Furthermore, the recyclability and reusability of the catalyst are also excellent.

Discovery of orally effective and safe GPR40 agonists by incorporating a chiral, rigid and polar sulfoxide into β-position to the carboxylic acid.

GPR40 is primarily expressed in pancreatic islet β-cells, and its activation by endogenous ligands of medium to long-chain free fatty acids or synthetic agonists is clinically proved to improve glycemic control by stimulating glucose-dependent insulin secretion. However, most of the reported agonists are highly lipophilic, which might cause lipotoxicity and the off-target effects in CNS. Particularly, the withdrawal of TAK-875 from clinical trials phase III due to liver toxicity concern threw doubt over the long-term safety of targeting GPR40. Improving the efficacy and the selectivity, thus enlarging the therapeutic window would provide an alternative to develop safe GPR40-targeted therapeutics. Herein, by employing an innovative "three-in-one" pharmacophore drug design strategy, the optimal structural features for GPR40 agonist was integrated into one functional group of sulfoxide, which was incorporated into the β-position of the propanoic acid core pharmacophore. As a result, the conformational constraint, polarity as well as chirality endowed by the sulfoxide significantly enhanced the efficacy, selectivity and ADMET properties of the novel (S)- 2-(phenylsulfinyl)acetic acid-based GPR40 agonists. The lead compounds (S)-4a and (S)-4s exhibited robust plasma glucose-lowering effects and insulinotropic action during an oral glucose tolerance test in C57/BL6 mice, excellent pharmacokinetic profile and little hepatobiliary transporter inhibition, marginal cell toxicities against human primary hepatocyte at 100μM.

3D-Printed Bioactive Scaffold Loaded with GW9508 Promotes Critical-Size Bone Defect Repair by Regulating Intracellular Metabolism.

The process of bone regeneration is complicated, and it is still a major clinical challenge to regenerate critical-size bone defects caused by severe trauma, infection, and tumor resection. Intracellular metabolism has been found to play an important role in the cell fate decision of skeletal progenitor cells. GW9508, a potent agonist of the free fatty acid receptors GPR40 and GPR120, appears to have a dual effect of inhibiting osteoclastogenesis and promoting osteogenesis by regulating intracellular metabolism. Hence, in this study, GW9508 was loaded on a scaffold based on biomimetic construction principles to facilitate the bone regeneration process. Through 3D printing and ion crosslinking, hybrid inorganic-organic implantation scaffolds were obtained after integrating 3D-printed β-TCP/CaSiO3 scaffolds with a Col/Alg/HA hydrogel. The 3D-printed β-TCP/CaSiO3 scaffolds had an interconnected porous structure that simulated the porous structure and mineral microenvironment of bone, and the hydrogel network shared similar physicochemical properties with the extracellular matrix. The final osteogenic complex was obtained after GW9508 was loaded into the hybrid inorganic-organic scaffold. To investigate the biological effects of the obtained osteogenic complex, in vitro studies and a rat cranial critical-size bone defect model were utilized. Metabolomics analysis was conducted to explore the preliminary mechanism. The results showed that 50 μM GW9508 facilitated osteogenic differentiation by upregulating osteogenic genes, including Alp, Runx2, Osterix, and Spp1 in vitro. The GW9508-loaded osteogenic complex enhanced osteogenic protein secretion and facilitated new bone formation in vivo. Finally, the results from metabolomics analysis suggested that GW9508 promoted stem cell differentiation and bone formation through multiple intracellular metabolism pathways, including purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, and taurine and hypotaurine metabolism. This study provides a new approach to address the challenge of critical-size bone defects.

GPR35 antagonist CID-2745687 attenuates anchorage-independent cell growth by inhibiting YAP/TAZ activity in colorectal cancer cells.

Background and purpose: GPR35, a member of the orphan G-protein-coupled receptor, was recently implicated in colorectal cancer (CRC). However, whether targeting GPR35 by antagonists can inhibit its pro-cancer role has yet to be answered. Experimental approach: We applied antagonist CID-2745687 (CID) in established GPR35 overexpressing and knock-down CRC cell lines to understand its anti-cell proliferation property and the underlying mechanism. Key results: Although GPR35 did not promote cell proliferation in 2D conditions, it promoted anchorage-independent growth in soft-agar, which was reduced by GPR35 knock-down and CID treatment. Furthermore, YAP/TAZ target genes were expressed relatively higher in GPR35 overexpressed cells and lower in GPR35 knock-down cells. YAP/TAZ activity is required for anchorage-independent growth of CRC cells. By detecting YAP/TAZ target genes, performing TEAD4 luciferase reporter assay, and examining YAP phosphorylation and TAZ protein expression level, we found YAP/TAZ activity is positively correlated to GPR35 expression level, which CID disrupted in GPR35 overexpressed cells, but not in GPR35 knock-down cells. Intriguingly, GPR35 agonists did not promote YAP/TAZ activity but ameliorated CID's inhibitory effect; GPR35-promoted YAP/TAZ activity was only partly attenuated by ROCK1/2 inhibitor. Conclusion and implications: GPR35 promoted YAP/TAZ activity partly through Rho-GTPase with its agonist-independent constitutive activity, and CID exhibited its inhibitory effect. GPR35 antagonists are promising anti-cancer agents that target hyperactivation and overexpression of YAP/TAZ in CRC.

Aminosalicylates target GPR35, partly contributing to the prevention of DSS-induced colitis

GPR35, a class A G-protein-coupled receptor, is considered an orphan receptor; the endogenous ligand and precise physiological function of GPR35 remain obscure. GPR35 is expressed relatively highly in the gastrointestinal tract and immune cells. It plays a role in colorectal diseases like inflammatory bowel diseases (IBDs) and colon cancer. More recently, the development of GPR35 targeting anti-IBD drugs is in solid request. Nevertheless, the development process is in stagnation due to the lack of a highly potent GPR35 agonist that is also active comparably in both human and mouse orthologs. Therefore, we proposed to find compounds for GPR35 agonist development, especially for the human ortholog of GPR35. As an efficient way to pick up a safe and effective GPR35 targeting anti-IBD drug, we screened Food and Drug Administration (FDA)-approved 1850 drugs using a two-step DMR assay. Interestingly, we found aminosalicylates, first-line medicine for IBDs whose precise target remains unknown, exhibited activity on both human and mouse GPR35. Among these, pro-drug olsalazine showed the most potency on GPR35 agonism, inducing ERK phosphorylation and β-arrestin2 translocation. In dextran sodium sulfate (DSS)-induced colitis, the protective effect on disease progression and inhibitory effect on TNFα mRNA expression, NF-κB and JAK-STAT3 pathway of olsalazine are compromised in GPR35 knock-out mice. The present study identified a target for first-line medicine aminosalicylates, highlighted that uncleaved pro-drug olsalazine is effective, and provided a new concept for the design of aminosalicylic GPR35 targeting anti-IBD drug.

Molecular docking studies of potent and selective orally bioavailable dihydro-pyrazole Gpr-40 agonists as Alpha-Glucosidase Inhibitors (AGIS)

Molecular docking studies of potent and selective orally bioavailable dihydro-pyrazole Gpr-40 agonists as Alpha-Glucosidase Inhibitors (AGIS)