33 research outputs found
ROLES OF SPHINGOSINE 1-PHOSPHATE RECEPTOR 2 (S1P2) IN NEURAL AND CANCER CELLS: IMPLICATION FOR PREVENTION OF CISPLATIN-INDUCED PERIPHERAL NEUROPATHY
No full textPh.DDOCTOR OF PHILOSOPH
CHARACTERIZING THE ROLE OF FREE FATTY ACID RECEPTORS (FFARs) IN BREAST CANCER CELLS
No full textPh.DDOCTOR OF PHILOSOPH
EVALUATING THE THERAPEUTIC POTENTIAL OF ORPHAN G-PROTEIN COUPLED RECEPTORS: GPR19 AND GPR17
No full textPh.DDOCTOR OF PHILOSOPH
Associations with metabolites in Chinese suggest new metabolic roles in Alzheimer’s and Parkinson’s diseases
No full textAbstract Metabolites are small intermediate products of cellular metabolism perturbed in a variety of complex disorders. Identifying genetic markers associated with metabolite concentrations could delineate disease-related metabolic pathways in humans. We tested genetic variants for associations with 136 metabolites in 1,954 Chinese from Singapore. At a conservative genome-wide threshold (3.7 x 10-10), we detected 1,899 variant-metabolite associations at 16 genetic loci. Three loci (ABCA7, A4GALT, GSTM2) represented novel associations with metabolites, with the strongest association observed between ABCA7 and d18:1/24:1 dihexosylceramide. Among 13 replicated loci, we identified six new variants independent of previously reported metabolite or lipid signals. We observed variant-metabolite associations at two loci (ABCA7, CHCHD2) that have been linked to neurodegenerative diseases. At SGPP1 and SPTLC3 loci, genetic variants showed preferential selectivity for sphingolipids with d16 (rather than d18) sphingosine backbone, including sphingosine-1-phosphate (S1P). Our results provide new genetic associations for metabolites and highlight the role of metabolites as intermediate modulators in disease metabolic pathways
Discovery of indolylpiperazinylpyrimidines with dual-target profiles at adenosine A2A and dopamine D2 receptors for Parkinson's disease treatment.
No full textParkinson's disease (PD) is a neurodegenerative disorder characterized by progressive loss of dopaminergic neurons in the substantia nigra of the human brain, leading to depletion of dopamine production. Dopamine replacement therapy remains the mainstay for attenuation of PD symptoms. Nonetheless, the potential benefit of current pharmacotherapies is mostly limited by adverse side effects, such as drug-induced dyskinesia, motor fluctuations and psychosis. Non-dopaminergic receptors, such as human A2A adenosine receptors, have emerged as important therapeutic targets in potentiating therapeutic effects and reducing the unwanted side effects. In this study, new chemical entities targeting both human A2A adenosine receptor and dopamine D2 receptor were designed and evaluated. Two computational methods, namely support vector machine (SVM) models and Tanimoto similarity-based clustering analysis, were integrated for the identification of compounds containing indole-piperazine-pyrimidine (IPP) scaffold. Subsequent synthesis and testing resulted in compounds 5 and 6, which acted as human A2A adenosine receptor binders in the radioligand competition assay (Ki = 8.7-11.2 μM) as well as human dopamine D2 receptor binders in the artificial cell membrane assay (EC50 = 22.5-40.2 μM). Moreover, compound 5 showed improvement in movement and mitigation of the loss of dopaminergic neurons in Drosophila models of PD. Furthermore, in vitro toxicity studies on compounds 5 and 6 did not reveal any mutagenicity (up to 100 μM), hepatotoxicity (up to 30 μM) or cardiotoxicity (up to 30 μM)
Manipulation of alcohol and short-chain fatty acids in the metabolome of commensal and virulent klebsiella pneumoniae by linolenic acid
No full text10.3390/microorganisms8050773Microorganisms8577
Hydrocarbon stapled B chain analogues of relaxin-3 retain biological activity
No full textAbstractRelaxin-3 or insulin-like peptide 7 (INSL7) is the most recently discovered relaxin/insulin-like family peptide. Mature relaxin-3 consists of an A chain and a B chain held by disulphide bonds. According to structure activity relationship studies, the relaxin-3 B chain is more important in binding and activating the receptor. RXFP3 (also known as Relaxin-3 receptor 1, GPCR 135, somatostatin- and angiotensin- like peptide receptor or SALPR) was identified as the cognate receptor for relaxin-3 by expression profiles and binding studies. Recent studies imply roles of this system in mediating stress and anxiety, feeding, metabolism and cognition. Stapling of peptides is a technique used to develop peptide drugs for otherwise undruggable targets. The main advantages of stapling include, increased activity due to reduced proteolysis, increased affinity to receptors and increased cell permeability. Stable agonists and antagonists of RXFP3 are crucial for understanding the physiological significance of this system. So far, agonists and antagonists of RXFP3 are peptides. In this study, for the first time, we have introduced stapling of the relaxin-3 B chain at 14th and 18th positions (14s18) and 18th and 22nd position (18s22). These stapled peptides showed greater helicity than the unstapled relaxin-3 B chain in circular dichroism analysis. Both stapled peptides bound RXFP3 and activated RXFP3 as observed in an inhibition of forskolin-induced cAMP assay and a ERK1/2 activation assay, although with different potencies. Therefore, we conclude that stapling of the relaxin3 B chain does not compromise its ability to activate RXFP3 and is a promising method for developing stable peptide agonists and antagonists of RXFP3 to aid relaxin-3/RXFP3 research
Butyric acid from probiotic staphylococcus epidermidis in the skin microbiome down-regulates the ultraviolet-induced pro-inflammatory IL-6 cytokine via short-chain fatty acid receptor
No full text10.3390/ijms20184477International Journal of Molecular Sciences2018447
A derivative of butyric acid, the fermentation metabolite of staphylococcus epidermidis, inhibits the growth of a staphylococcus aureus strain isolated from atopic dermatitis patients
No full text10.3390/toxins11060311Toxins11631
