Displaying all 15 publications

Abstract:
Sort:
  1. Mohd Fakharul Zaman Raja Yahya, Hasidah Mohd Sidek
    Kajian ini melibatkan pemantauan perkembangan parasitemia dan taburan morfologi Plasmodium berghei sewaktu infeksi parasit dalam mencit, serta penentuan kesan infeksi P. berghei ke atas pengisyaratan MAP kinase eritrosit perumah. Analisis mikroskop ke atas slaid calitan darah terwarna-Giemsa yang disediakan daripada mencit terinfeksi-P. berghei (strain PZZ1/00) menunjukkan darjah parasitemia mencapai sehingga 70% dalam masa dua minggu selepas penyuntikan parasit. Morfologi cecincin dan trofozoit parasit dicerap dengan jelas sepanjang tempoh infeksi manakala morfologi skizon parasit hanya dicerap dengan ketara selepas hari ketiga selepas penyuntikan parasit. Pemblotan Western [antibodi primer: anti-MAP kinase (ERK-1/2 tak terfosfat) monoklon; antibodi sekunder: anti-IgG, poliklon terkonjugat-HRP] ke atas protein sitosol eritrosit terinfeksi-P. berghei (70% parasitemia) susulan pemisahan SDS-PAGE menunjukkan bahawa keamatan protein imunoreaktif-MAP kinase eritrosit berberat molekul 42 dan 44 kDa didapati meningkat secara signifikan (p<0.05) pada 70% iaitu peningkatan sebanyak 21.5% dan 22.3% masing-masing berbanding sampel kawalan tanpa infeksi. Samada kesan infeksi P. berghei (70% parasitemia) ke atas pengisyaratan MAP kinase perumah ini berkaitan dengan pengaktifan enzim ini perlu dikaji dengan lebih lanjut.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  2. Thent ZC, Froemming GRA, Ismail ABM, Fuad SBSA, Muid S
    Iran J Basic Med Sci, 2020 Sep;23(9):1155-1163.
    PMID: 32963737 DOI: 10.22038/ijbms.2020.45296.10545
    Objectives: Since bisphenol A (BPA) induces bone loss and phytoestrogens enhance the osteoblastogenesis by binding to the non-classical and classical oestrogen receptors, respectively, the present study was aimed to observe the osteoprotective effect of phytoestrogens on BPA-induced osteoblasts in hFOB 1.19 cells.

    Materials and Methods: All groups of hFOB 1.19 cells were induced with 12.5 μg/ml of BPA except the control (Ctrl) group. Meanwhile, treated groups received phytoestrogens; Daidzein (Dz), Genistein (Gt), Equol (Eq) and 17β-oestradiol (Est) in different concentrations for 24 hr duration.

    Results: We found that the protein expression of non-classical oestrogen-related receptor (ERRG) was highly expressed in BPA group, whereas classical oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERβ) were relatively increased with phytoestrogens treatment under BPA exposure. The dense actin cytoskeletal filaments were also observed. qRT-PCR showed up-regulation of mitogen-activated protein kinase 3 (MAPK3) and G protein-coupled receptor 30 (GPR30) expressions; significant down-regulation of ERRG and up-regulation of ERα and ERβ were observed in phytoestrogens-treated cells, which was supported by the increased expressions of oestrogen receptor 1 (ESR1) and oestrogen receptor 2 (ESR2).

    Conclusion: Phytoestrogens improved the deteriorative effect of BPA via down-regulation of ERRG in hFOB 1.19 cells. This study showed that the efficacy of consumption of phytoestrogens in rendering them as potential therapeutic strategy in combating the adverse bone effects of BPA.

    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  3. Thou EMH, Choo QC, Chew CH
    Eur. Cytokine Netw., 2020 Jun 01;31(2):59-67.
    PMID: 32933893 DOI: 10.1684/ecn.2020.0446
    Atherosclerosis is initiated when lipoproteins are trapped by proteoglycans in the arterial intima. Macrophages play a vital role in this disease, especially in the formation of foam cells and the regulation of pro-inflammatory responses. They also participate in plaque stabilization through the secretion of matrix metalloproteinases. Studies have reported the role of ADAMTS proteases in osteoarthritis and atherosclerotic lesions.In the present study, we have studied the effect of interleukin-17A (IL-17A) on the expression of ADAMTS-5 in the macrophage cell line THP-1. The results show that the mRNA and protein expression levels of ADAMTS-5 were significantly upregulated when differentiated THP-1 cells were treated with 100 ng/mL of IL-17A for 24 h with maximum ADAMTS-5 mRNA expression levels obtained at 8 h of stimulation. Subsequent inhibition studies showed that IL-17A upregulation of ADAMTS-5 was mediated through ERK and JNK pathways in THP-1 cells. Phosphorylation studies revealed that the expression of ADAMTS-5 transcripts was upregulated by IL-17A through the activation of p-c-Raf (S338), p-MEK1/2 (Ser217/221), p-p44/42 MAPK (Thr202/Tyr204), and p-Elk1 (Ser383). ERK1/2 siRNA transfection further confirmed that the ERK pathway is involved in the expression of ADAMTS-5 in IL-17A-stimulated THP-1 cells.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  4. Mayer AMS, Hall ML, Lach J, Clifford J, Chandrasena K, Canton C, et al.
    Mar Drugs, 2021 Sep 07;19(9).
    PMID: 34564169 DOI: 10.3390/md19090506
    Manzamines are complex polycyclic marine-derived β-carboline alkaloids with reported anticancer, immunostimulatory, anti-inflammatory, antibacterial, antiviral, antimalarial, neuritogenic, hyperlipidemia, and atherosclerosis suppression bioactivities, putatively associated with inhibition of glycogen synthase kinase-3, cyclin-dependent kinase 5, SIX1, and vacuolar ATPases. We hypothesized that additional, yet undiscovered molecular targets might be associated with Manzamine A's (MZA) reported pharmacological properties. We report here, for the first time, that MZA selectively inhibited a 90 kDa ribosomal protein kinase S6 (RSK1) when screened against a panel of 30 protein kinases, while in vitro RSK kinase assays demonstrated a 10-fold selectivity in the potency of MZA against RSK1 versus RSK2. The effect of MZA on inhibiting cellular RSK1 and RSK2 protein expression was validated in SiHa and CaSki human cervical carcinoma cell lines. MZA's differential binding and selectivity toward the two isoforms was also supported by computational docking experiments. Specifically, the RSK1-MZA (N- and C-termini) complexes appear to have stronger interactions and preferable energetics contrary to the RSK2-MZA ones. In addition, our computational strategy suggests that MZA binds to the N-terminal kinase domain of RSK1 rather than the C-terminal domain. RSK is a vertebrate family of cytosolic serine-threonine kinases that act downstream of the ras-ERK1/2 (extracellular-signal-regulated kinase 1/2) pathway, which phosphorylates substrates shown to regulate several cellular processes, including growth, survival, and proliferation. Consequently, our findings have led us to hypothesize that MZA and the currently known manzamine-type alkaloids isolated from several sponge genera may have novel pharmacological properties with unique molecular targets, and MZA provides a new tool for chemical-biology studies involving RSK1.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/metabolism
  5. Lee SH, Jaganath IB, Manikam R, Sekaran SD
    BMC Complement Altern Med, 2013 Oct 20;13:271.
    PMID: 24138815 DOI: 10.1186/1472-6882-13-271
    BACKGROUND: Lung cancer constitutes one of the malignancies with the greatest incidence and mortality rates with 1.6 million new cases and 1.4 million deaths each year. Prognosis remains poor due to deleterious development of multidrug resistance resulting in less than 15% lung cancer patients reaching five years survival. We have previously shown that Phyllanthus induced apoptosis in conjunction with its antimetastastic action. In the current study, we aimed to determine the signaling pathways utilized by Phyllanthus to exert its antimetastatic activities.

    METHODS: Cancer 10-pathway reporter array was performed to screen the pathways affected by Phyllanthus in lung carcinoma cell line (A549) to exert its antimetastatic effects. Results from this array were then confirmed with western blotting, cell cycle analysis, zymography technique, and cell based ELISA assay for human total iNOS. Two-dimensional gel electrophoresis was subsequently carried out to study the differential protein expressions in A549 after treatment with Phyllanthus.

    RESULTS: Phyllanthus was observed to cause antimetastatic activities by inhibiting ERK1/2 pathway via suppression of Raf protein. Inhibition of this pathway resulted in the suppression of MMP2, MMP7, and MMP9 expression to stop A549 metastasis. Phyllanthus also inhibits hypoxia pathway via inhibition of HIF-1α that led to reduced VEGF and iNOS expressions. Proteomic analysis revealed a number of proteins downregulated by Phyllanthus that were involved in metastatic processes, including invasion and mobility proteins (cytoskeletal proteins), transcriptional proteins (proliferating cell nuclear antigen; zinc finger protein), antiapoptotic protein (Bcl2) and various glycolytic enzymes. Among the four Phyllanthus species tested, P. urinaria showed the greatest antimetastatic activity.

    CONCLUSIONS: Phyllanthus inhibits A549 metastasis by suppressing ERK1/2 and hypoxia pathways that led to suppression of various critical proteins for A549 invasion and migration.

    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/genetics; Mitogen-Activated Protein Kinase 3/metabolism
  6. Chien SY, Hsu CH, Lin CC, Chuang YC, Lo YS, Hsi YT, et al.
    Environ Toxicol, 2017 Aug;32(8):2085-2092.
    PMID: 28383207 DOI: 10.1002/tox.22423
    Nasopharyngeal carcinoma (NPC), a tumor arising from epithelial cells that cover the surface and line the nasopharynx, is a rare malignancy worldwide but is prevalent in certain geographical areas, such as Southern Asia (Taiwan, Hong Kong, Singapore, Malaysia, and Southern China) and North Africa. Despite advances in diagnostic techniques and improvements in treatment modalities, the prognosis of NPC remains poor. Therefore, an effective chemotherapy regimen that enhances tumor sensitivity to chemotherapeutics is urgently required. Nimbolide, derived from Azadirachta indica, has a wide range of beneficial effects, including anti-inflammatory and anticancer properties. The present study evaluated the antitumor activity of nimbolide in NPC cells and its underlying mechanisms. Our results revealed that the treatment of HONE-1 cells with nimbolide potently inhibited cell viability. Moreover, nimbolide led to cell cycle arrest, which subsequently activated caspase-3, -8, and -9 and poly (ADP-ribose) polymerase to induce cell apoptosis. Moreover, nimbolide induced Bik, Bax, and t-Bid expression in HONE-1 cells. The results indicated that nimbolide induces apoptosis through the modulation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) pathways. Nimbolide induces apoptosis in human NPC cells and is a potential chemopreventive agent against NPC proliferation. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 2085-2092, 2017.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/metabolism
  7. Gautam V, Nimmanpipug P, Zain SM, Rahman NA, Lee VS
    Molecules, 2021 Jul 27;26(15).
    PMID: 34361694 DOI: 10.3390/molecules26154540
    Extracellular signal-regulated kinases 1 and 2 (ERK1/2) play key roles in promoting cell survival and proliferation through the phosphorylation of various substrates. Remarkable antitumour activity is found in many inhibitors that act upstream of the ERK pathway. However, drug-resistant tumour cells invariably emerge after their use due to the reactivation of ERK1/2 signalling. ERK1/2 inhibitors have shown clinical efficacy as a therapeutic strategy for the treatment of tumours with mitogen-activated protein kinase (MAPK) upstream target mutations. These inhibitors may be used as a possible strategy to overcome acquired resistance to MAPK inhibitors. Here, we report a class of repeat proteins-designed ankyrin repeat protein (DARPin) macromolecules targeting ERK2 as inhibitors. The structural basis of ERK2-DARPin interactions based on molecular dynamics (MD) simulations was studied. The information was then used to predict stabilizing mutations employing a web-based algorithm, MAESTRO. To evaluate whether these design strategies were successfully deployed, we performed all-atom, explicit-solvent molecular dynamics (MD) simulations. Two mutations, Ala → Asp and Ser → Leu, were found to perform better than the original sequence (DARPin E40) based on the associated energy and key residues involved in protein-protein interaction. MD simulations and analysis of the data obtained on these mutations supported our predictions.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/metabolism
  8. Foo SC, Yusoff FM, Imam MU, Foo JB, Ismail N, Azmi NH, et al.
    Biotechnol Rep (Amst), 2019 Mar;21:e00296.
    PMID: 30581767 DOI: 10.1016/j.btre.2018.e00296
    In this study, anti-proliferative effects of C. calcitrans extract and its fucoxanthin rich fraction (FxRF) were assessed on human liver HepG2 cancer cell line. Efficacy from each extract was determined by cytotoxicity assay, morphological observation, and cell cycle analysis. Mechanisms of action observed were evaluated using multiplex gene expression analysis. Results showed that CME and FxRF induced cytotoxicity to HepG2 cells in a dose and time-dependent manner. FxRF (IC50: 18.89 μg.mL-1) was found to be significantly more potent than CME (IC50: 87.5 μg.mL-1) (p 
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  9. Jabbarzadeh Kaboli P, Leong MP, Ismail P, Ling KH
    Pharmacol Rep, 2019 Feb;71(1):13-23.
    PMID: 30343043 DOI: 10.1016/j.pharep.2018.07.005
    BACKGROUND: Berberine is an alkaloid plant-based DNA intercalator that affects gene regulation, particularly expression of oncogenic and tumor suppressor proteins. The effects of berberine on different signaling proteins remains to be elucidated. The present study aimed to identify the effects of berberine against key oncogenic proteins in breast cancer cells.

    METHODS: Molecular docking and molecular dynamics simulations were used for EGFR, p38, ERK1/2, and AKT. The effects of berberine and lapatinib on MAPK and PI3K pathways in MDA-MB231 and MCF-7 cells were evaluated using immunoflorescence assays, and the amounts of phosphorylated kinases were compared to total kinases after treating with different concentrations of berberine.

    RESULTS: Simulations showed berberine accurately interacted with EGFR, AKT, P38, and ERK1/2 active sites in silico (scores = -7.57 to -7.92 Kcal/mol) and decreased the levels of active forms of corresponding enzymes in both cell lines; however, berberine binding to p38 showed less stability. Cytotoxicity analysis indicated that MDA-MB231 cells were resistant to berberine compared to MCF-7 cells [72 h IC50 = 50 versus 15 μM, respectively). Also, lapatinib strongly activated AKT but suppressed EGFR in MDA-MB231 cells. The activity of EGFR, AKT, P38, and ERK1/2 were affected by berberine; however, berberine dramatically reduced EGFR and AKT phosphorylation.

    CONCLUSION: By way of its multikinase inhibitory effects, berberine might be a useful replacement for lapatinib, an EGFR inhibitor which can cause acquired drug resistance in patients.

    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/antagonists & inhibitors*; Mitogen-Activated Protein Kinase 3/metabolism; Mitogen-Activated Protein Kinase 3/chemistry
  10. Boroumand Moghaddam A, Moniri M, Azizi S, Abdul Rahim R, Bin Ariff A, Navaderi M, et al.
    Genes (Basel), 2017 Oct 20;8(10).
    PMID: 29053567 DOI: 10.3390/genes8100281
    Green products have strong potential in the discovery and development of unique drugs. Zinc oxide nanoparticles (ZnO NPs) have been observed to have powerful cytotoxicity against cells that cause breast cancer. The present study aims to examine the cell cycle profile, status of cell death, and pathways of apoptosis in breast cancer cells (MCF-7) treated with biosynthesized ZnO NPs. The anti-proliferative activity of ZnO NPs was determined using MTT assay. Cell cycle analysis and the mode of cell death were evaluated using a flow cytometry instrument. Quantitative real-time-PCR (qRT-PCR) was employed to investigate the expression of apoptosis in MCF-7 cells. ZnO NPs were cytotoxic to the MCF-7 cells in a dose-dependent manner. The 50% growth inhibition concentration (IC50) of ZnO NPs at 24 h was 121 µg/mL. Cell cycle analysis revealed that ZnO NPs induced sub-G₁ phase (apoptosis), with values of 1.87% at 0 μg/mL (control), 71.49% at IC25, 98.91% at IC50, and 99.44% at IC75. Annexin V/propidium iodide (PI) flow cytometry analysis confirmed that ZnO NPs induce apoptosis in MCF-7 cells. The pro-apoptotic genes p53, p21, Bax, and JNK were upregulated, whereas anti-apoptotic genes Bcl-2, AKT1, and ERK1/2 were downregulated in a dose-dependent manner. The arrest and apoptosis of MCF-7 cells were induced by ZnO NPs through several signalling pathways.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  11. Sayem ASM, Giribabu N, Karim K, Si LK, Muniandy S, Salleh N
    Biomed Pharmacother, 2018 Apr;100:132-141.
    PMID: 29428660 DOI: 10.1016/j.biopha.2018.02.008
    Sex-steroids play important role in modulating uterine functions. We hypothesized that these hormones affect expression of proteins in the uterus related to thyroid hormone action. Therefore, changes in expression levels of receptors for thyroid hormone (TRα-1 and TRβ-1), thyroid stimulating hormone (TSHR), vitamin D (VDR) and retinoid acid (RAR) as well as extracellular signal-regulated kinase (ERK1/2) in uterus were investigated under sex-steroid influence.

    METHODS: Two rat models were used: (i) ovariectomised, sex-steroid replaced and (ii) intact, at different phases of oestrous cycle. A day after completion of sex-steroid treatment or following identification of oestrous cycle phases, rats were sacrificed and expression and distribution of these proteins in uterus were identified by Western blotting and immunohistochemistry, respectively.

    RESULTS: Expression of TRα-1, TRβ-1, TSHR, VDR, RAR and ERK1/2 in uterus was higher following estradiol (E2) treatment and at estrus phase of oestrous cycle when E2levels were high. A relatively lower expression was observed following progesterone (P) treatment and at diestrus phases of oestrous cycle when P levels were high. Under E2influence, TRα, TRβ, TSHR, VDR, RAR and ERK1/2 were distributed in luminal and glandular epithelia while under P influence, TSHR, VDR abn RAR were distributed in the stroma.

    CONCLUSIONS: Differential expression and distribution of TRα-1, TRβ-1, TSHR, VDR, RAR and ERK1/2 in different uterine compartments could explain differential action of thyroid hormone, TSH, vitamin D, and retinoic acid in uterus under different sex-steroid conditions.

    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  12. Mohammed Abdul KS, Rayadurgam J, Faiz N, Jovanović A, Tan W
    J Cell Mol Med, 2020 09;24(18):10924-10934.
    PMID: 32794652 DOI: 10.1111/jcmm.15721
    In the present study, we have investigated potential cardioprotective properties of Isosteviol analogue we recently synthesized and named JC105. Treatment of heart embryonic H9c2 cells with JC105 (10 μM) significantly increased survival of cells exposed to hypoxia-reoxygenation. JC105 (10 μM) activated ERK1/2, DRP1 and increased levels of cardioprotective SUR2A in hypoxia-reoxygenation, but did not have any effects on ERK1/2, DRP1 and/or SUR2A in normoxia. U0126 (10 μM) inhibited JC105-mediated phosphorylation of ERK1/2 and DRP1 without affecting AKT or AMPK, which were also not regulated by JC105. Seahorse bioenergetic analysis demonstrated that JC105 (10 μM) did not affect mitochondria at rest, but it counteracted all mitochondrial effects of hypoxia-reoxygenation. Cytoprotection afforded by JC105 was inhibited by U0126 (10 μM). Taken all together, these demonstrate that (a) JC105 protects H9c2 cells against hypoxia-reoxygenation and that (b) this effect is mediated via ERK1/2. The unique property of JC105 is that selectively activates ERK1/2 in cells exposed to stress, but not in cells under non-stress conditions.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/metabolism
  13. Tan BL, Norhaizan ME, Chan LC
    PMID: 30519270 DOI: 10.1155/2018/7826576
    Manilkara zapota (L.) P. Royen, called sapodilla, or locally known as ciku, belongs to the family Sapotaceae. We found that Manilkara zapota leaf water extract has cytotoxic effect against human hepatocellular carcinoma (HepG2) cell line in our earlier study. Therefore, this study aimed to explore the anticancer properties of Manilkara zapota leaf water extract in HepG2 cells. We also aimed to unravel yet undiscovered mechanisms and identified several expressed genes whose functions in cytotoxicity activity of Manilkara zapota leaf water extract in HepG2 cells have not been well-studied. The apoptosis and intracellular reactive oxygen species (ROS) activities were analyzed using Annexin V-propidium iodide staining and dichlorodihydrofluorescein diacetate, respectively, by NovoCyte Flow Cytometer. Bax and Bcl-2 expression were assessed using Enzyme-Linked Immunosorbent Assay. The associated molecular pathways were evaluated by quantitative real-time PCR. Overall analyses revealed that Manilkara zapota leaf water extract can increase percentage of early apoptotic cells, induce the formation of ROS, upregulate c-Jun N-terminal kinase 1 (JNK1) and inducible nitric oxide synthase (iNOS), and reduce Akt1 and vascular endothelial growth factor A (VEGFA) transcriptional activities. Our data suggest that Manilkara zapota leaf water extract can suppress the growth of HepG2 cells via modulation of ERK1/2/Akt1/JNK1 transcriptional expression.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3
  14. Tabana YM, Hassan LE, Ahamed MB, Dahham SS, Iqbal MA, Saeed MA, et al.
    Microvasc Res, 2016 09;107:17-33.
    PMID: 27133199 DOI: 10.1016/j.mvr.2016.04.009
    We recently reported the antineovascularization effect of scopoletin on rat aorta and identified its potential anti-angiogenic activity. Scopoletin could be useful as a systemic chemotherapeutic agent against angiogenesis-dependent malignancies if its antitumorigenic activity is investigated and scientifically proven using a suitable human tumor xenograft model. In the present study, bioassay-guided (anti-angiogenesis) phytochemical investigation was conducted on Nicotiana glauca extract which led to the isolation of scopoletin. Further, anti-angiogenic activity of scopoletin was characterized using ex vivo, in vivo and in silico angiogenesis models. Finally, the antitumorigenic efficacy of scopoletin was studied in human colorectal tumor xenograft model using athymic nude mice. For the first time, an in vivo anticancer activity of scopoletin was reported and characterized using xenograft models. Scopoletin caused significant suppression of sprouting of microvessels in rat aortic explants with IC50 (median inhibitory concentration) 0.06μM. Scopoletin (100 and 200mg/kg) strongly inhibited (59.72 and 89.4%, respectively) vascularization in matrigel plugs implanted in nude mice. In the tumor xenograft model, scopoletin showed remarkable inhibition on tumor growth (34.2 and 94.7% at 100 and 200mg/kg, respectively). Tumor histology revealed drastic reduction of the extent of vascularization. Further, immunostaining of CD31 and NG2 receptors in the histological sections confirmed the antivascular effect of scopoletin in tumor vasculature. In computer modeling, scopoletin showed strong ligand affinity and binding energies toward the following angiogenic factors: protein kinase (ERK1), vascular endothelial growth factor A (VEGF-A), and fibroblast growth factor 2 (FGF-2). These results suggest that the antitumor activity of scopoletin may be due to its strong anti-angiogenic effect, which may be mediated by its effective inhibition of ERK1, VEGF-A, and FGF-2.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/metabolism*; Mitogen-Activated Protein Kinase 3/chemistry
  15. Arifin SA, Paternoster S, Carlessi R, Casari I, Ekberg JH, Maffucci T, et al.
    Biochim Biophys Acta Mol Cell Biol Lipids, 2018 09;1863(9):1132-1141.
    PMID: 29883799 DOI: 10.1016/j.bbalip.2018.06.007
    The gastrointestinal tract is increasingly viewed as critical in controlling glucose metabolism, because of its role in secreting multiple glucoregulatory hormones, such as glucagon like peptide-1 (GLP-1). Here we investigate the molecular pathways behind the GLP-1- and insulin-secreting capabilities of a novel GPR119 agonist, Oleoyl-lysophosphatidylinositol (Oleoyl-LPI). Oleoyl-LPI is the only LPI species able to potently stimulate the release of GLP-1 in vitro, from murine and human L-cells, and ex-vivo from murine colonic primary cell preparations. Here we show that Oleoyl-LPI mediates GLP-1 secretion through GPR119 as this activity is ablated in cells lacking GPR119 and in colonic primary cell preparation from GPR119-/- mice. Similarly, Oleoyl-LPI-mediated insulin secretion is impaired in islets isolated from GPR119-/- mice. On the other hand, GLP-1 secretion is not impaired in cells lacking GPR55 in vitro or in colonic primary cell preparation from GPR55-/- mice. We therefore conclude that GPR119 is the Oleoyl-LPI receptor, upstream of ERK1/2 and cAMP/PKA/CREB pathways, where primarily ERK1/2 is required for GLP-1 secretion, while CREB activation appears dispensable.
    Matched MeSH terms: Mitogen-Activated Protein Kinase 3/genetics; Mitogen-Activated Protein Kinase 3/metabolism
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links