GPR119 Agonists Research Articles

Protective effects of GPR120 agonist-programmed macrophages on renal interstitial fibrosis in unilateral ureteral obstruction (UUO) rats

Macrophages in the kidney play different roles in renal interstitial fibrosis (RIF) depending on their phenotypes. M2 phenotype macrophages are believed to protect the kidney against RIF. Free fatty acid receptor GPR120 is expressed in macrophages, and its activation induces macrophage transition to M2 phenotype. In this study, the effects of GPR120 agonist-programmed macrophages on RIF were investigated. The peritoneal macrophages collected from rats were incubated with GPR120 agonist TUG891 in vitro for 24 h, and then they were transplanted autologously to the kidney with ureteral obstruction by intrarenal injection for 7 days on the same day following unilateral ureteral obstruction (UUO) operation. RIF was identified by Masson trichrome histological staining, and the expression of RIF-related proteins was analyzed by immunohistochemistry and western blot. It was observed that TUG891-programmed macrophages up-regulated the expression of CD206 and arginase-1 while the expression of interleukin-6 and tumor necrosis factor-α were down-regulated. RIF in rats was significantly increased following UUO, which was markedly alleviated by TUG891-programmed macrophages but not untreated macrophages. TUG891-programmed macrophages inhibited the abnormal expression of TGF-β1 and SMAD2. The abnormal expression of epithelial-mesenchymal transition (EMT)-related proteins including vimentin, α-SMA and β-catenin was also significantly decreased in rats with transplantation of TUG891-programmed macrophages as compared to UUO rats. This study suggests that autologous administration of peritoneal macrophages programmed in vitro by GPR120 agonist to kidney has a protective effect against RIF following UUO.

Психоневрологические нарушения у животных с ишемией головного мозга на фоне сахарного диабета и их коррекция новым агонистом GPR119 и его комбинациями с метформином и цитиколином

Сахарный диабет (СД) 2 типа значительно повышает риск развития инсульта и выбор гипогликемической терапии может оказать влияние не только на вероятность развития, но и на тяжесть течения нарушения мозгового кровообращения (НМК). Цель: оценить влияние комбинированного введения агониста GPR119 с метформином и цитиколином на выраженность психоневрологических нарушений у животных с НМК на фоне СД. Методика. Исследование проведено на крысах линии Wistar, которым моделировали фокальную ишемию ГМ на фоне 28 дневного стрептозотоцин-никотинамид-индуцированного СД. Агонист рецептора GPR119 (дипиарон) и его комбинацию с метформином вводили с первого дня развития СД, а цитиколин - после моделирования НМК. Психоневрологические нарушения оценивались с использованием шкал «Combs & D’Alecy» и «Garcia», и тестов «Открытое поле», «Ротарод», УРПИ и ТЭИ. Результаты и обсуждение. Введение метформина приводило к нормализации уровня гликемии, но не снижало выраженность неврологического дефицита при последующем моделировании НМК. По сравнению с контролем в группах, получавших дипиарон и в большей степени его комбинацию с метформином, помимо улучшения контроля гликемии наблюдалось значительное снижение объема инфаркта и отёка мозга, а также выраженности психоневрологических нарушений у выживших животных (p<0,05). Введение цитиколина без гипогликемической терапии не приводило к снижению уровня неврологического дефицита по сравнению с контрольной группой, при этом добавление цитиколина к гипогликемической терапии значимо не снижало тяжесть течения НМК. Заключение. Комбинированное введение агониста GPR119 и метформина животным с экспериментальной ишемией ГМ на фоне СД значительно повышает терапевтический потенциал обоих препаратов, обеспечивая лучший контроль уровня гликемии и снижая выраженность психоневрологического дефицита при моделировании НМК. Type 2 diabetes mellitus (DM2) significantly increases the risk of stroke, and the choice of hypoglycemic therapy may influence not only a probability of stroke but also severity of cerebrovascular disease. Objective: To evaluate the effect of combination treatment with a GPR119 agonist, metformin and citicoline on severity of neurological disorders in animals with stroke and diabetes. Cerebral ischemia was modeled by intraluminal occlusion of the middle cerebral artery (OMCA). Methods. The study was performed on Wistar rats with 28-day streptozotocin-nicotinamide-induced diabetes. The GPR119 receptor agonist (dipiaron) and its combination with metformin were administered starting from the first day of DM, and citicoline was administered after the induction of brain ischemia. Behavioral and neurological disorders were evaluated using the Combs & D’Alecy and Garcia scales, and the open field, Rotarod, and active and passive avoidance tests. Results. The metformin treatment normalized glycemia but did not alleviate severity of the neurological deficit induced by subsequent OMCA. The groups treated with dipiaron and its combination with metformin, in addition to improved glycemic control, showed significant decreases in brain infarction volume and edema and the severity of neurological disorders in surviving animals compared to the control (p<0.05). Administration of citicoline without the hypoglycemic therapy reduced the neurological deficit in comparison with the control group. Addition of citicoline to the hypoglycemic therapy did not significantly reduce the severity of brain ischemia. Conclusion. The combination treatment of animals with brain ischemia and diabetes with the GPR119 agonist and metformin significantly enhanced the therapeutic potential of both drugs evident as a better glycemic control and alleviated severity of the neurological deficit following OMCA.

RETRACTED ARTICLE: GPR39 agonist TC-G 1008 ameliorates IL-1β-induced chondrocyte senescence

We, the Editors and Publisher of the journal Artificial Cells, Nanomedicine, and Biotechnology, have retracted the following article: Huading Lu, Dawei Wang, Huizi Li, Junlong Zhong, Yimin Lin, Xianghe Xu & Bin Wang (2019) GPR39 agonist TC-G 1008 ameliorates IL-1β-induced chondrocyte senescence. Artificial Cells, Nanomedicine, and Biotechnology, 47(1), 2612–2617, DOI: 10.1080/21691401.2019.1626405 Since publication, the authors found that they were unable to obtain the same results following the performance of further experiments. As this directly impacts the reported results and conclusions the authors alerted the issue to the Editor and Publisher and all have agreed to retract the article to ensure correction of the scholarly record. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as ‘Retracted’.

SCO-267, a GPR40 Full Agonist, Improves Glycemic and Body Weight Control in Rat Models of Diabetes and Obesity.

The GPR40/FFA1 receptor is a G-protein-coupled receptor expressed in the pancreatic islets and enteroendocrine cells. Here, we report the pharmacological profiles of (3S)-3-cyclopropyl-3-{2-[(1-{2-[(2,2-dimethylpropyl)(6-methylpyridin-2-yl)carbamoyl]-5-methoxyphenyl}piperidin-4-yl)methoxy]pyridin-4-yl}propanoic acid (SCO-267), a novel full agonist of GPR40. Ca2+ signaling and insulin and glucagon-like peptide-1 (GLP-1) secretion were evaluated in GPR40-expressing CHO, MIN6, and GLUTag cells. Hormone secretions and effects on fasting glucose were tested in rats. Single or repeated dosing effects were evaluated in neonatally streptozotocin-induced diabetic rats (N-STZ-1.5 rats), diet-induced obese (DIO) rats, and GPR40-knockout (Ffar1-/- ) mice. Treatment with SCO-267 activated Gq signaling in both high- and low-FFAR1-expressing CHO cells, stimulated insulin secretion in MIN6 cells, and induced GLP-1 release in GLUTag cells. When administered to normal rats, SCO-267 increased insulin, glucagon, GLP-1, glucose-dependent insulinotropic peptide, and peptide YY (PYY) secretions under nonfasting conditions. These results show the full agonistic property of SCO-267 against GPR40. Hypoglycemia was not induced in SCO-267-treated rats during the fasting condition. In diabetic N-STZ-1.5 rats, SCO-267 was highly effective in improving glucose tolerance in single and 2-week dosing studies. DIO rats treated with SCO-267 for 2 weeks showed elevated plasma GLP-1 and PYY levels, reduced food intake, and decreased body weight. In wild-type mice, SCO-267 induced GLP-1 secretion, food intake inhibition, and body weight reduction; however, these effects were abolished in Ffar1-/- mice, indicating a GPR40-dependent mechanism. In conclusion, SCO-267 stimulated islet and gut hormone secretion, improved glycemic control in diabetic rats, and decreased body weight in obese rats. These data suggest the therapeutic potential of SCO-267 for the treatment of diabetes and obesity.

2333-PUB: CPL207-280, a Potent and Safe GPR40 Agonist for the treatment of Type 2 Diabetes

Targeting GPR40 receptor has been proposed as novel modality for patients with insufficient blood sugar control or in tolerating popular drugs. It belongs to G-protein coupled receptors family and is highly expressed in pancreatic β-cells where it mediates free fatty acid-induced insulin secretion. Although several synthetic GPR40 agonists have been generated none of them found use in the clinic predominantly due to safety issues. Therefore, the greatest interest in the field has been focused on safety and favorable pharmacokinetics. In previous study we showed a new, effective GPR40 agonist, which displayed promising safety profile in vitro. Here we show the safety, biological and pharmacological effects of CPL207-280 in rats and non-human primate (NHP) T2D models. Pharmacokinetic studies in rats and NHP showed very high bioavailability (F) (80% and 87% in rats and monkeys, respectively) of the compound CPL207-280 and favorable half-time (t1/2kel): 4,75 h in rats and 3,95 h in monkeys which can protect against compound accumulation (especially in the liver) during long term administration. CPL207-280 increased insulin secretion and showed dose-dependent improvement (at a dose range of 3-100 mg/kg) in GTT test in ZDSD rats and at a dose 15 mg/kg in diabetic NHP study. During toxicology study the maximum tolerated dose (MTD) for CPL207-280 was found at a dose of 1000 mg/kg and 500 mg/kg in rats and monkeys, respectively. In the 14-days (dose range finding) DRF study the (no observable adverse effect level) NOAEL was found at the level of 300 mg/kg and 100 mg/kg in rats and monkeys, respectively. Additionally, during a 28-days study in diabetic NHP at dose 15 mg/kg administrated p.o., no significant side effects were observed and all haematology and biochemical parameters including: total bile acids (TBA), total bilirubin (TB), ALT, AST, GGT were not changed compared to control group. This clearly demonstrates that CPL207-280 has a great potential to become a safe and effective candidate for treatment of T2D. Disclosure K. Bazydlo-Guzenda: Employee; Self; Celon Pharma S.A. P. Buda: Employee; Self; Celon Pharma S.A. I. Kozlowska: Employee; Self; Celon Pharma S.A. M. Mach: Employee; Self; Celon Pharma S.A. M. Teska-Kaminska: Employee; Self; Celon Pharma S.A. F. Stelmach: Employee; Self; Celon Pharma S.A. M. Wasinska-Kalwa: Employee; Self; Celon Pharma S.A. K. Galazka: Employee; Self; Celon Pharma S.A. K.K. Dubiel: Employee; Self; Celon Pharma S.A. J.S. Pieczykolan: Employee; Self; Celon Pharma S.A. M. Wieczorek: Other Relationship; Self; Celon Pharma S.A. Funding National Centre for Research and Development

1162-P: DA-1241, a Novel GPR119 Agonist, Improves Hyperglycaemia by Inhibiting Hepatic Gluconeogenesis and Enhancing Insulin Secretion via Stimulation of GLP-1 Secretion

Unlike other G protein-coupled receptor (GPR)119 agonists, DA-1241 has shown long-term beneficial effects on glucose and lipid metabolism in previous studies. In this study, we investigated the antidiabetic effects of DA-1241 in vitro and in vivo. The efficacy of DA-1241 was evaluated by assessing the changes in glucagon-like peptide-1 (GLP-1) levels, gluconeogenesis, and hepatic autophagy. DA-1241 was administrated to high-fat diet (HFD)-fed C57BL/6J mice for 12 weeks (n=34), and serum insulin and GLP-1 levels were measured by oral glucose tolerance tests at week 8. The effects of DA-1241 on gluconeogenic enzyme expression and autophagic flow were evaluated in HepG2 cells and livers isolated from LC3-GFP-transgenic mice. DA-1241 improved oral glucose tolerance (no significant effect on intraperitoneal glucose tolerance test) with an increase in serum GLP-1 and insulin levels. Fasting blood glucose level decreased, and the insulinogenic index was improved after DA-1241 treatment in HFD-fed mice. However, no significant increase in insulin secretion in INS1E cells and isolated mouse islet with DA1241 treatment. DA-1241 reduced gluconeogenic enzyme expression and blocked autophagic flow in HepG2 cells. Additionally, DA1241 induced GFP fragmentation in liver from LC3-GFP-transgenic mice. These findings suggested that DA-1241 augmented glucose-dependent insulin release via improvement in GLP-1 secretion, and reduced hepatic gluconeogenesis, which might be associated with autophagic blockage, leading to improved glycaemic control. Disclosure J. Kim: None. Y. Kim: None. R. Kim: None. M. Kim: None. H. Park: None. M. Lee: None. Y. Cho: None. J. Bae: None. S. Lee: None. I. Lee: None. H. Lee: None. C. Kim: None. E. Kang: None.

200-OR: Role of Delta Cell Gpr120 in the Regulation of Islet Function and Glucose Control

Gpr120 is a long-chain fatty acid receptor expressed in pancreatic islets, where it inhibits the secretion of somatostatin (SST) by the δ cell. SST is a negative regulator of glucoregulatory hormone secretion. However, the precise role of Gpr120 in the regulation of insulin and glucagon secretion is still unclear, as well as the specific islet cell(s) type(s) involved. Objective: This study aimed at defining the role of pancreatic δ-cell Gpr120 signaling in the regulation of islet function and glucose homeostasis. Methods: Insulin and SST secretion was measured in isolated islets from WT, Gpr120 KO and Gpr40 KO mice in 1h static incubation in the presence of 2.8 or 16.7 mM glucose with or without synthetic (Compound A, Cpd A) or endogenous (alpha-linolenic, eicosapentaenoic or docosahexaenoic acid) Gpr120 agonists. Glucagon and SST secretion was measured after 1h static incubation in response to arginine with or without Cpd A. Cpd A was administered orally to WT male mice before an oral Glucose Tolerance Test or an Arginine Test, and blood glucose and insulin or glucagon plasma levels were measured. Results: In isolated islets from WT mice, activation of Gpr120 with either Cpd A or endogenous agonists dose-dependently inhibited glucose-stimulated SST secretion, and concomitantly increased glucose-stimulated insulin secretion. Cpd A also inhibited SST secretion and potentiated glucagon secretion in response to arginine in low glucose conditions. The effects of Cpd A were unaltered in Gpr40 KO islets but disappeared in Gpr120 KO islets. Oral administration of Cpd A improved glucose tolerance and potentiated both glucose-induced insulin secretion and arginine-induced glucagon secretion. Conclusion: The results demonstrate that Gpr120 activation in islets inhibits SST secretion, potentiates insulin and glucagon secretion, and improves glycemic control. Disclosure M.L. Croze: None. S. Granziera: None. K. Vivot: None. A. Szpigel: None. J. Ghislain: None. V. Poitout: None. Funding Société Francophone du Diabète; Montreal Diabetes Research Center; Natural Sciences and Engineering Research Council of Canada

1161-P: SCO-267, a GPR40 Full Agonist, Improves Glycemic and Body Weight Control More Than That by Fasiglifam in Rat Models of Diabetes and Obesity

GPR40/FFAR1 is a G-protein-coupled receptor expressed in pancreatic islets and enteroendocrine cells. SCO-267 is a novel full agonist of GPR40 being developed as a treatment for type 2 diabetes and obesity. The efficacy of SCO-267 was investigated in cells and animal models of diabetes and obesity. In animal studies, the efficacy of SCO-267 was compared with that of fasiglifam, a clinically effective GPR40 agonist. SCO-267 treatment activated Gq signaling in both high and low GPR40-expressing CHO cells, stimulated insulin secretion in MIN6 cells, and induced GLP-1 release in GLUTag cells. In rats, SCO-267 increased insulin, glucagon, GLP-1, GIP, and PYY secretion, without hypoglycemia. In the neonatal streptozotocin (N-STZ)-1.5 rat, a diabetic model with impaired beta-cell function, compared to fasiglifam, SCO-267 was more effective in stimulating insulin and GLP-1 secretion, and improving glucose tolerance. In a single dose study using N-STZ-1.5 rats, 0.3 mg/kg SCO-267 (Cmax 0.023 μg/mL) and 3 mg/kg fasiglifam (Cmax 6.2 μg/mL) exhibited similar glucose-lowering efficacies. In a two-week dosing study of N-STZ-1.5 rats, glucose tolerance was more effectively improved by 1 mg/kg SCO-267 (Cmax, 0.139 μg/mL; AUC0-24hr, 0.626 μg h/mL) than by 10 mg/kg fasiglifam (Cmax, 39.8 μg/mL; AUC0-24hr, 254.6 μg h/mL). Diet-induced obese rats treated with SCO-267 for 2 weeks showed elevated plasma GLP-1 and PYY, reduced food intake, and decreased body weight, whereas fasiglifam-treated rats were weight-neutral. The reduction in body weight by SCO-267 was abolished in GPR40 knockout mice. Plasma protein binding of SCO-267 was similar across species (99.6-99.7%), indicating that similar compound exposure may induce therapeutic effects in humans. SCO-267 showed good pharmacokinetic and safety profiles in preclinical studies. These results suggest that SCO-267 treatment may result in effective glycemic and body weight control in patients. Disclosure Y. Moritoh: Employee; Self; SCOHIA PHARMA, Inc. H. Ueno: Employee; Self; Takeda Pharmaceutical Company Limited. R. Ito: Employee; Self; Takeda Pharmaceutical Company Limited. S. Abe: Employee; Self; SCOHIA PHARMA, Inc. H. Miyashita: Employee; Self; Takeda Pharmaceutical Company Limited. H. Ogino: Employee; Self; Takeda Pharmaceutical Company Limited. M. Ookawara: Employee; Self; SCOHIA PHARMA, Inc. Y. Ishimura: Employee; Self; Takeda Pharmaceutical Company Limited. Y. Miyamoto: None. T. Yoshihara: Employee; Self; Takeda Pharmaceutical Company Limited. Employee; Spouse/Partner; Takeda Pharmaceutical Company Limited. Y. Tsujihata: Employee; Self; Takeda Pharmaceutical Company Limited. K. Takeuchi: Employee; Self; Takeda Pharmaceutical Company Limited. N. Nishigaki: Employee; Self; Takeda Pharmaceutical Company Limited. Y. Yamada: Board Member; Self; SCOHIA PHARMA, Inc. M. Watanabe: Employee; Self; SCOHIA PHARMA, Inc. Funding Takeda Pharmaceutical Company Limited; SCOHIA PHARMA, Inc.

41-OR: Store-Operated Ca2+ Entry Activated by STIM1 Plays an Essential Role in GPR40-Mediated GIIS Potentiation

Background: Store-operated Ca2+ entry (SOCE) is activated by endoplasmic reticulum (ER) Ca2+ sensor STIM1 which senses depletion of Ca2+ from the ER, and induces extracellular Ca2+ influx through Orai1 to the cytosol to maintain intracellular Ca2+ homeostasis in various cell types, however the role of SOCE in pancreatic β-cells remains largely unknown. GPR40 plays an important role in potentiation of glucose-induced insulin secretion (GIIS) by long-chain fatty acids and its activation enhances Ca2+-release from ER by activating inositol 1,4,5-triphosphate (IP3) receptor. Therefore, we hypothesized that SOCE contributed to GPR40-mediated GIIS potentiation. To test the hypothesis, we examined the role of SOCE modulator, STIM1 in MIN6 cells and β-cell specific STIM1-deficient mice (βSTIM1 cKO). Methods: Fasiglifam(fas) was used for GPR40 agonist. STIM1 or Orai1 knockdowned (KD) MIN6 cells were analyzed for insulin secretion or intracellular Ca2+-dynamics. MIN6 cells were also transfected with pEX-SP-YFP-STIM1(23-685) and Orai1-CFP to analyze intracellular trafficking of STIM1 in response to fas. Insulin secretion from βSTIM1 cKO islets and OGTT was also analyzed to reveal physiological role of STIM1. Results: STIM1 or Orai1 KD MIN6 cells and islets from βSTIM1 cKO similarly abolished fas-mediated potentiation of GIIS and fas-induced elevation of intracellular Ca2+ levels, while there was little effect on GIIS itself. STIM1-YFP was rapidly translocated from the ER to the plasma membrane and merged with Orai1-CFP in response to fas which was cancelled by pretreatment of IP3 receptor antagonist, xestospongin C. In OGTT, blood glucose levels were similar in control mice and βSTIM1 cKO without fas administration, however fas-mediated glucose lowering and insulin increasing effect were significantly lower compared with control. Conclusion: GPR40 signal activates STIM1 and SOCE activated by STIM1 is essential for GPR40-mediated potentiation of GIIS. Disclosure R. Usui: None. D. Yabe: Advisory Panel; Self; Abbott. Research Support; Self; Astellas Pharma Inc. Speaker's Bureau; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp & Dohme Corp., Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Sanofi K.K., Taisho Pharmaceutical Co., Ltd., Takeda Pharmaceutical Company Limited. M. Fauzi: None. A. Botagarova: None. H. Goto: None. S. Tokumoto: None. H. Tatsuoka: None. Y. Tahara: None. S. Kobayashi: None. T. Manabe: None. Y. Baba: None. T. Kurosaki: None. M. Ogura: Research Support; Self; Takeda Pharmaceutical Company Limited. Speaker's Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Daiichi Sankyo Company, Limited, Eli Lilly and Company, Kyowa Hakko Kirin Co., Ltd., Merck & Co., Inc., Mitsubishi Tanabe Pharma Corporation, Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Sanofi, Takeda Pharmaceutical Company Limited. K. Nagashima: None. N. Inagaki: Research Support; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Japan Tobacco Inc., Kyowa Hakko Kirin Co., Ltd., Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novartis Pharmaceuticals Corporation, Ono Pharmaceutical Co., Ltd., Sanofi, Sumitomo Dainippon Pharma Co., Ltd., Takeda Pharmaceutical Company Limited. Funding Japan Society for the Promotion of Science; Japan Association for Diabetes Education and Care

Pharmacological stimulation of G–protein coupled receptor 40 alleviates cytokine-induced epithelial barrier disruption in airway epithelial Calu-3 cells

Impairment of airway tight junctions induced by elevated levels of proinflammatory cytokines is implicated in the pathogenesis of inflammatory airway diseases. Pharmacological stimulation of G–protein coupled receptor (GPR) 40, a receptor of polyunsaturated fatty acids, have recently been shown to promote tight junction assembly in airway epithelial cells under non-inflammatory conditions. However, roles of GPR40 in regulating airway epithelial integrity in response to inflammatory insults are unknown. This study was aimed to investigate the effect of GPR40 stimulation on proinflammatory cytokine (TNFα and IL–1β)-induced tight junction disruption in human airway epithelial Calu–3 cells using GW9508, a GPR40 agonist. We found that stimulation of GPR40 by GW9508 attenuated the cytokine–induced airway epithelial barrier leakage as analyzed by measurements of transepithelial electrical resistance and transepithelial flux of fluorescently labeled dextran (molecular weight of 4 kDa). Furthermore, GW9508 prevented the cytokine-induced dislocalization of zonula occludens (ZO)–1, occludin and claudin–1. The barrier-protective effect of GW9508 was abolished by a GPR40 antagonist, but not a GPR120 antagonist. Immunofluorescence staining of NF–ĸB indicated that GW9508 had no effect on cytokine-induced NF–ĸB activation. Intriguingly, GW9508 inhibited cytokine-induced airway epithelial barrier disruption through suppression of extracellular signal–regulated kinase (ERK) phosphorylation in a phospholipase C (PLC) and calcium/calmodulin–dependent protein kinase kinase beta (CaMKKβ)-dependent manner. Collectively, this study uncovered the novel role of GPR40 in preventing cytokine–induced tight junction disruption in airway epithelial cells through mechanisms involving PLC–CaMKKβ-mediated suppression of ERK signaling. Pharmacological stimulation of GPR40 may be beneficial in the treatment of airway diseases.

G protein-coupled receptor 40 activation ameliorates dextran sulfate sodium-induced colitis in mice via the upregulation of glucagon-likepeptide-2

G protein-coupled receptor (GPR) 40 is a receptor for long-chain free fatty acids that enhances glucagon-like peptide (GLP)-2 production in intestinal L-cells. GLP-2 and its analogs have reported to increase remission rates in patients with Crohn's disease and improve experimental colitis in rodents. In the present study, we investigated the ameliorative effect of GPR40 activation in a dextran sulfate sodium (DSS)-induced murine colitis model using a specific GPR40 agonist, AS2034178. The daily administration of AS2034178 attenuated DSS-induced increases in the disease activity index, the shortening of the colon length, and the histological colonic injury, and increased the myeloperoxidase (MPO) activity and expression of inflammatory cytokines, in a dose-dependent manner. These effects were abolished by treatment with DC260126, a GPR40 antagonist, or GLP-2 (3-33), a GLP-2 antagonist. GPR40 was expressed in the colonic mucosa, which was colocalized with proglucagon, a precursor of GLP-2. AS2034178 significantly increased the amount of GLP-2 in the colonic tissue, which was abolished by DC260126 but not GLP-2 (3-33). Furthermore, AS2034178 significantly promoted the healing of DSS-induced colitis. These findings suggest that GPR40 activation ameliorates DSS-induced colitis in mice by enhancing GLP-2 production. Thus, GPR40 is a potential target for the treatment of IBD.

Visible-Light-Triggered Cyanoalkylation of para-Quinone Methides and Its Application to the Synthesis of GPR40 Agonists.

Cyanoalkylated diarylmethanes with biological and pharmacological potentials were synthesized from para-quinone methides and cyanoalkylating reagents through a photocatalytic process. This protocol is operationally simple and mild and has high efficiency, which gave the corresponding products in moderate to good yields. The synthetic utility of this work has been illustrated in the efficient synthesis of GPR40 agonists, which play an important role in FA-induced glucose-sensitive insulin secretion.

Design, synthesis and biological evaluation of indane derived GPR40 agoPAMs

GPR40 (FFAR1 or FFA1) is a G protein-coupled receptor, primarily expressed in pancreatic islet β-cells and intestinal enteroendocrine cells. When activated by fatty acids, GPR40 elicits increased insulin secretion from islet β-cells only in the presence of elevated glucose levels. Towards this end, studies were undertaken towards discovering a novel GPR40 Agonist whose mode of action is via Positive Allosteric Modulation of the GPR40 receptor (AgoPAM). Efforts were made to identify a suitable GPR40 AgoPAM tool molecule to investigate mechanism of action and de-risk liver toxicity of GPR40 AgoPAMs due to reactive acyl-glucuronide (AG) metabolites.

In vivo Characterization of a Selective, Orally Available, and Brain Penetrant Small Molecule GPR139 Agonist.

Recently, our group along with another demonstrated that GPR139 can be activated by L-phenylalanine (L-Phe) and L-tryptophan (L-Trp) at physiologically relevant concentrations. GPR139 is discretely expressed in brain, with highest expression in medial habenula. Not only are the endogenous ligands catecholamine/serotonin precursors, but GPR139 expressing areas can directly/indirectly regulate the activity of catecholamine/serotonin neurons. Thus, GPR139 appears expressed in an interconnected circuit involved in mood, motivation, and anxiety. The aim of this study was to characterize a selective and brain penetrant GPR139 agonist (JNJ-63533054) in relevant in vivo models. JNJ-63533054 was tested for its effect on c-fos activation in the habenula and dorsal striatum. In vivo microdialysis experiments were performed in freely moving rats to measure basal levels of serotonin or dopamine (DA) in prefrontal cortex (mPFC) and nucleus accumbens (NAc). Finally, the compound was profiled in behavioral models of anxiety, despair, and anhedonia. The agonist (10–30 mg/kg, p.o.) did not alter c-fos expression in medial habenula or dorsal striatum nor neurotransmitter levels in mPFC or NAc. JNJ-63533054 (10 mg/kg p.o.) produced an anhedonic-like effect on urine sniffing, but had no significant effect in tail suspension, with no interaction with imipramine, no effect on naloxone place aversion, and no effect on learned helplessness. In the marble burying test, the agonist (10 mg/kg p.o.) produced a small anxiolytic-like effect, with no interaction with fluoxetine, and no effect in elevated plus maze (EPM). Despite GPR139 high expression in medial habenula, an area with connections to limbic and catecholaminergic/serotoninergic areas, the GPR139 agonist had no effect on c-fos in medial habenula. It did not alter catecholamine/serotonin levels and had a mostly silent signal in in vivo models commonly associated with these pathways. The physiological function of GPR139 remains elusive.

GPR55-Mediated Effects in Colon Cancer Cell Lines

The cannabinoid-responsive G protein-coupled receptor GPR55 and its endogenous ligand L-α-lysophosphatidyl­inositol (LPI) have been reported to play a role in several cancers. A proliferation-enhancing effect of GPR55 has been described for several cancer cell lines and LPI has been found elevated in cancer patients. The aim of this study was to investigate whether GPR55 signaling had an effect on the proliferation of colon cancer cell lines. Using cell viability assays and Western blotting, we show that stable overexpression of the GPR55 receptor led to a growth advantage of SW480 cells per se. Proliferation of native colon cancer cell lines, however, was not affected by pharmacological manipulation of GPR55. Interestingly though, GPR55 signaling was responsive to treatment with both the GPR55 agonist LPI and the antagonist CID16020046 in the overexpressing cancer cell lines. This was evident through significantly increased or decreased levels of phosphorylated ERK1/2, respectively. Taken together, our findings suggest that GPR55 is constitutively activated in overexpressing colon cancer cells affecting ERK1/2 phosphorylation and cell proliferation.

GPR55 controls functional differentiation of self-renewing epithelial progenitors for salivation.

GPR55, a lipid-sensing receptor, is implicated in cell cycle control, malignant cell mobilization, and tissue invasion in cancer. However, a physiological role for GPR55 is virtually unknown for any tissue type. Here, we localize GPR55 to self-renewing ductal epithelial cells and their terminally differentiated progeny in both human and mouse salivary glands. Moreover, we find GPR55 expression downregulated in salivary gland mucoepidermoid carcinomas and GPR55 reinstatement by antitumor irradiation, suggesting that GPR55 controls renegade proliferation. Indeed, GPR55 antagonism increases cell proliferation and function determination in quasiphysiological systems. In addition, Gpr55-/- mice present ~50% enlarged submandibular glands with many more granulated ducts, as well as disordered endoplasmic reticuli and with glycoprotein content. Next, we hypothesized that GPR55 could also modulate salivation and glycoprotein content by entraining differentiated excretory progeny. Accordingly, GPR55 activation facilitated glycoprotein release by itself, inducing low-amplitude Ca2+ oscillations, as well as enhancing acetylcholine-induced Ca2+ responses. Topical application of GPR55 agonists, which are ineffective in Gpr55-/- mice, into adult rodent submandibular glands increased salivation and saliva glycoprotein content. Overall, we propose that GPR55 signaling in epithelial cells ensures both the life-long renewal of ductal cells and the continuous availability of saliva and glycoproteins for oral health and food intake.

Zinc-induced activation of GPR39 regulates glucose homeostasis through glucose-dependent insulinotropic polypeptide secretion from enteroendocrine K-cells.

The role of Zn2+-sensing receptor GPR39 on glucose homeostasis and incretin regulation was assessed in enteroendocrine L- and K-cells. Anti-hyperglycaemic, insulinotropic and incretin secreting properties of Zn2+ were explored in normal, diabetic and incretin receptor knockout mice. Compared to intraperitoneal injection, oral administration of Zn2+ (50 μmol/kg body weight) with glucose (18 mmol/kg) in lean mice reduced the glycaemic excursion by 25-34% (p < 0.05-p < 0.001) and enhanced glucose-induced insulin release by 46-48% (p < 0.05-p < 0.01). In diabetic mice, orally administered Zn2+ lowered glucose by 24-31% (p < 0.01) and augmented insulin release by 32% (p < 0.01). In glucagon like peptide-1 (GLP-1) receptor knockout mice, Zn2+ reduced glucose by 15-28% (p < 0.05-p < 0.01) and increased insulin release by 35-43% (p < 0.01). In contrast Zn2+ had no effect on responses of glucose-dependent insulinotropic polypeptide (GIP) receptor knockout mice. Consistent with this, Zn2+ had no effect on circulating total GLP-1 whereas GIP release was stimulated by 26% (p < 0.05) in lean mice. Immunocytochemistry demonstrated GPR39 expression on mouse enteroendocrine L- and K-cells, GLUTag cells and pGIP/Neo STC-1 cells. Zn2+ had a direct effect on GIP secretion from pGIPneo STC-1 cells, increasing GIP secretion by 1.3-fold. GPR39 is expressed on intestinal L- and K-cells, and stimulated GIP secretion plays an integral role in mediating enhanced insulin secretion and glucose tolerance following oral administration of Zn2+. This suggests development of potent and selective GPR39 agonists as a therapeutic approach for diabetes.

Targeting CB1 and GPR55 Endocannabinoid Receptors as a Potential Neuroprotective Approach for Parkinson’s Disease

Cannabinoid CB1 receptors (CB1R) and the GPR55 receptor are expressed in striatum and are potential targets in the therapy of Parkinson's disease (PD), one of the most prevalent neurodegenerative diseases in developed countries. The aim of this paper was to address the potential of ligands acting on those receptors to prevent the action of a neurotoxic agent, MPP+, that specifically affects neurons of the substantia nigra due to uptake via the dopamine DAT transporter. The SH-SY5Y cell line model was used as it expresses DAT and, therefore, is able to uptake MPP+ that inhibits complex I of the respiratory mitochondrial chain and leads to cell death. Cells were transfected with cDNAs coding for either or both receptors. Receptors in cotransfected cells formed heteromers as indicated by the in situ proximity ligation assays. Cell viability was assayed by oxygen rate consumption and by the bromide-based MTT method. Assays of neuroprotection using two concentrations of MPP+ showed that cells expressing receptor heteromers were more resistant to the toxic effect. After correction by effects on cell proliferation, the CB1R antagonist, SR141716, afforded an almost full neuroprotection in CB1R-expressing cells even when a selective agonist, ACEA, was present. In contrast, SR141716 was not effective in cells expressing CB1/GPR55 heteromeric complexes. In addition, an agonist of GPR55, CID1792197, did not enhance neuroprotection in GPR55-expressing cells. These results show that neurons expressing heteromers are more resistant to cell death but question the real usefulness of CB1R, GPR55, and their heteromers as targets to afford PD-related neuroprotection.

Synthesis and evaluation of novel fused pyrimidine derivatives as GPR119 agonists

A novel series of fused pyrimidine derivatives were designed, synthesized and evaluated as GPR119 agonists. Among them, cyclohexene fused compounds (tetrahydroquinazolines) showed greater GPR119 agonistic activities than did dihydrocyclopentapyrimidine and tetrahydropyridopyrimidine scaffolds. Analogues (16, 19, 26, 28, 42) bearing endo-N-Boc-nortropane amine and fluoro-substituted aniline exhibited better EC50 values (0.27–1.2 μM) though they appeared to be partial agonists.

HM47118A, a novel insulinotropic GPR119 agonist and potential oral antidiabetic agent

AimsThe G protein-coupled receptor 119 (GPR119), mainly expressed in the pancreas and gastrointestinal tract, increases the intracellular cyclic AMP accumulation, enhances glucose-dependent insulin secretion from pancreatic β cells, and promotes glucagon-like peptide-1 (GLP-1) production by intestinal L cells. We investigated the activities of a novel GPR119 agonist, HM47118A, in vitro and in vivo. MethodsIn vitro HM47118A activities were evaluated in several cell lines. Mice, rats, and dogs were administered single intravenous or oral doses of HM47118A to evaluate its pharmacokinetics, while its antidiabetic efficacy was evaluated in Zucker diabetic fatty (ZDF) rats. ResultsThe half-maximal effective concentrations of HM47118A were 2.0 and 21.8 nM for the activation of human GPR119 in GPR119-CRE-bla CHO-K1 cells and stimulation of GLP-1 secretion by GLUTag cells, respectively. HM47118A increased insulin secretion by MIN-6 cells and the proliferation of NIT-1 pancreatic β cells. The compound showed favorable pharmacokinetic profiles in all three animal models. Administration of HM47118A but not sitagliptin to ZDF rats for 56 days significantly reduced the blood glucose and glycated hemoglobin (HbA1c) levels, increased postprandial insulin levels, and preserved the pancreatic β cell mass. ConclusionsHM47118A showed significant antidiabetic potential and may be an effective oral treatment for diabetes.