GABA receptors mediate prolonged inhibition in the brain and are important for keeping neuronal excitation and inhibition in a healthy balance. However, under excitotoxic/ischemic conditions, GABA receptors are downregulated by dysregulated endocytic trafficking and can no longer counteract the severely enhanced excitation, eventually triggering neuronal death. Recently, we developed interfering peptides targeting protein-protein interactions involved in downregulating the receptors.
View Article and Find Full Text PDFClass-B1 G-protein-coupled receptors (GPCRs) are an important family of clinically relevant drug targets that remain difficult to investigate via high-throughput screening and in animal models. Here, we engineered PAClight1, a novel genetically encoded sensor based on a class-B1 GPCR (the human PAC1 receptor, hmPAC1R) endowed with high dynamic range (Δ/ = 1100%), excellent ligand selectivity, and rapid activation kinetics ( = 1.15 s).
View Article and Find Full Text PDFNociceptin/orphanin-FQ (N/OFQ) is a recently appreciated critical opioid peptide with key regulatory functions in several central behavioral processes including motivation, stress, feeding, and sleep. The functional relevance of N/OFQ action in the mammalian brain remains unclear due to a lack of high-resolution approaches to detect this neuropeptide with appropriate spatial and temporal resolution. Here we develop and characterize NOPLight, a genetically encoded sensor that sensitively reports changes in endogenous N/OFQ release.
View Article and Find Full Text PDFGABA receptor-mediated inhibition is indispensable for maintaining a healthy neuronal excitation/inhibition balance. Many neurological diseases are associated with a disturbed excitation/inhibition balance and downregulation of GABA receptors due to enhanced sorting of the receptors to lysosomal degradation. A key event triggering the downregulation of the receptors is the phosphorylation of S867 in the GABA subunit mediated by CaMKIIβ.
View Article and Find Full Text PDFThe molecular code that controls synapse formation and maintenance in vivo has remained quite sparse. Here, we identify that the secreted protein Adamtsl3 functions as critical hippocampal synapse organizer acting through the transmembrane receptor DCC (deleted in colorectal cancer). Traditionally, DCC function has been associated with glutamatergic synaptogenesis and plasticity in response to Netrin-1 signaling.
View Article and Find Full Text PDFGenetically encoded indicators engineered from G-protein-coupled receptors are important tools that enable high-resolution in vivo neuromodulator imaging. Here, we introduce a family of sensitive multicolor norepinephrine (NE) indicators, which includes nLightG (green) and nLightR (red). These tools report endogenous NE release in vitro, ex vivo and in vivo with improved sensitivity, ligand selectivity and kinetics, as well as a distinct pharmacological profile compared with previous state-of-the-art GRAB indicators.
View Article and Find Full Text PDFNociceptin/orphanin-FQ (N/OFQ) is a recently appreciated critical opioid peptide with key regulatory functions in several central behavioral processes including motivation, stress, feeding, and sleep. The functional relevance of N/OFQ action in the mammalian brain remains unclear due to a lack of high-resolution approaches to detect this neuropeptide with appropriate spatial and temporal resolution. Here we develop and characterize NOPLight, a genetically encoded sensor that sensitively reports changes in endogenous N/OFQ release.
View Article and Find Full Text PDFThe glucagon-like peptide-1 receptor (GLP1R) is a broadly expressed target of peptide hormones with essential roles in energy and glucose homeostasis, as well as of the blockbuster weight-loss drugs semaglutide and liraglutide. Despite its large clinical relevance, tools to investigate the precise activation dynamics of this receptor with high spatiotemporal resolution are limited. Here, we introduce a novel genetically encoded sensor based on the engineering of a circularly permuted green fluorescent protein into the human GLP1R, named GLPLight1.
View Article and Find Full Text PDFNeural differentiation, synaptic transmission, and action potential propagation depend on membrane sphingolipids, whose metabolism is tightly regulated. Mutations in the ceramide transporter CERT (CERT1), which is involved in sphingolipid biosynthesis, are associated with intellectual disability, but the pathogenic mechanism remains obscure. Here, we characterize 31 individuals with de novo missense variants in CERT1.
View Article and Find Full Text PDFBackground: The present study was designed to develop an improved in vitro regeneration system for Dioscorea bulbifera using mature nodal explants. Direct organogenesis from nodal segments was achieved by culturing the nodal explants on Murashige and Skoog medium supplemented with 3.5 mgl 6-benzylaminopurine (BAP).
View Article and Find Full Text PDFCerebral ischemia is the leading cause for long-term disability and mortality in adults due to massive neuronal death. Currently, there is no pharmacological treatment available to limit progressive neuronal death after stroke. A major mechanism causing ischemia-induced neuronal death is the excessive release of glutamate and the associated overexcitation of neurons (excitotoxicity).
View Article and Find Full Text PDFGABA receptors control neuronal excitability via slow and prolonged inhibition in the central nervous system. One important function of GABA receptors under physiological condition is to prevent neurons from shifting into an overexcitation state which can lead to excitotoxic death. However, under ischemic conditions, GABA receptors are downregulated, fostering over-excitation and excitotoxicity.
View Article and Find Full Text PDFOne important function of GABA receptors is the control of neuronal activity to prevent overexcitation and thereby excitotoxic death, which is a hallmark of cerebral ischemia. Consequently, sustained activation of GABA receptors with the selective agonist baclofen provides neuroprotection in and models of cerebral ischemia. However, excitotoxic conditions severely downregulate the receptors, which would compromise the neuroprotective effectiveness of baclofen.
View Article and Find Full Text PDFTranscriptional silencing induced by hypermethylation of CpG islands in the promoter regions of genes is believed to be an important mechanism of carcinogenesis in human cancers including epithelial ovarian cancer (EOC). Previously published data on gene methylation of EOC focused mainly on single gene or on cancer tissues. Objectives of the study were to estimate the promoter hypermethylation status of and genes in circulating blood of EOC patients and to determine their association with clinicopathological features of EOC.
View Article and Find Full Text PDFBackground: The protein coded by the cystathionine β synthase (CBS) gene acts as a catalyzer and converts homocysteine to cystathionine. Impairment of the CBS gene leads to homocystinuria by cystathionine β synthase deficiency which is linked to Coronary Artery Disease. A number of polymorphisms studies have been performed on the cystathionine β synthase gene.
View Article and Find Full Text PDFIn the original publication, third author name was incorrectly published as "Ab Rashid Mir". The correct name should read as "Rashid Mir".
View Article and Find Full Text PDFEscalated PD-L1 expression has been identified during malignant transformation in a number of cancer types and helps cancer cells escape an effective anti-tumor immune response. The mechanisms underlying escalated production of PD-L1 in many cancers, however, are still far from clear. We studied PD-L1, STAT3 and STAT5 mRNA expression using qRT-PCR in 72 BCR/ABL1 negative myeloproliferative neoplasm (MPN) patients (39 polycythemia vera and 33 essential thrombocythemia).
View Article and Find Full Text PDFThe influence of Estrogen Receptor 1 (ESR1) gene -397T>C (PvuII) and -351A>G (XbaI) polymorphisms on the risk of development of coronary artery disease (CAD) in the north Indian population was analysed. We hypothesized that ESR1 gene polymorphisms may influence the susceptibility to CAD through variation in Estrogen Receptor α (ERα) expression. To assess this concept, we evaluated ERα mRNA expression in blood plasma of CAD patients.
View Article and Find Full Text PDFBackground: Epithelial ovarian cancer continues to be a deleterious threat to women as it is asymptomatic and is typically detected in advanced stages. Cogent non-invasive biomarkers are therefore needed which are effective in apprehending the disease in early stages. Recently, miRNA deregulation has shown a promising magnitude in ovarian cancer tumorigenesis.
View Article and Find Full Text PDFRelaxin, a peptide hormone has emerged as a cardioprotective agent against the heart failure and has been found to protect cardiac muscle cells against hypoxia/reoxygenation injury under in vitro conditions. The present study was conducted to study its possible role in activating the Nrf2/HO-1 signaling pathway in cardiomyocytes, as a means to counter hypoxia associated oxidative damage and cell death. H9C2 cell line was induced with chemical hypoxia alone or together with relaxin.
View Article and Find Full Text PDF: Catechol--methyltransferase (COMT) plays a central role in DNA repair and estrogen-induced carcinogenesis. The nonsynonymous single nucleotide polymorphism (SNP) in exon 4 G > A or Val108 > 158Met or rs4680 G > A influences COMT enzyme activity. The three phenotypes of the COMT enzyme activities include COMT A/A with low enzyme activity, COMT A/G with medium enzyme activity and COMT G/G with high enzyme activity.
View Article and Find Full Text PDFGABA has always been an inviting target in the etiology and treatment of epilepsy. The GABRA1, GABRG2, and GABRD genes provide instructions for making α1, ϒ2, and δ subunits of GABAA receptor protein respectively. GABAA is considered as one of the most important proteins and has found to play an important role in many neurological disorders.
View Article and Find Full Text PDFHeme oxygenase-1 (HO-1) is considered to be the main protein in diseases arising as a result of oxidative and inflammatory insults. Tremendous research has been carried out on HO-1 since years, pertaining its cytoprotective effect against oxidative injury and other cellular stresses. HO-1, by regulating intracellular levels of pro-oxidant heme, or by other benefits of its by-products such as carbon monoxide (CO) and biliverdin (BV) had become an important candidate protein to be up-regulated to combat diverse stressful events.
View Article and Find Full Text PDFPlatelet-derived growth factor receptor has been implicated in many malignant and non-malignant diseases. Platelet-derived growth factor receptor-α is a tyrosine kinase and a side target for imatinib, a revolutionary drug for the treatment of chronic myeloid leukemia that has dramatically improved the survival of chronic myeloid leukemia patients. Given the importance of platelet-derived growth factor receptor in platelet development and its inhibition by imatinib, it was intriguing to analyze the role of platelet-derived growth factor receptor-α in relation to imatinib treatment in the development of imatinib-induced thrombocytopenia in chronic myeloid leukemia patients.
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