The hypothalamic arcuate nucleus (ARC) contains two main populations of neurons essential for energy homeostasis: neuropeptide Y (NPY) neurons, which are orexigenic and stimulate food intake, and proopiomelanocortin (POMC) neurons, which have an anorexigenic effect. Located near the blood-brain barrier, ARC neurons sense blood-borne signals such as leptin, insulin, and glucose. Exogenous substances, such as nicotine, can also alter ARC neuron activity and energy balance.
View Article and Find Full Text PDFMecamylamine, a noncompetitive blocker of nicotinic acetylcholine receptors (nAChRs), is the racemic mixture of two stereoisomers: S-(+)-mecamylamine (S-mec) and R-(-)-mecamylamine (R-mec), with distinct interactions with α4β2 nAChRs. It has been shown that mecamylamine increases glutamate release and excites serotonergic (5-HT) neurons in the dorsal raphe nucleus (DRN). In this study, we separately evaluated the effects of S-mec and R-mec on 5-HT neuron excitability.
View Article and Find Full Text PDFAccumulating evidence indicates that insulin-mediated signaling in the brain may play important roles in regulating neuronal function. Alterations to insulin signaling are associated with the development of neurological disorders including Alzheimer's disease and Parkinson's disease. Also, hyperglycemia and insulin resistance have been associated with seizure activity and brain injury.
View Article and Find Full Text PDFZika virus (ZIKV) is an emerging mosquito-borne flavivirus associated with congenital Zika syndrome and Guillain-Barré syndrome in adults. The recombinant ZIKV envelope (E) antigen can be useful for serodiagnosis of ZIKV infection and for monitoring immune responses during preclinical and clinical ZIKV vaccine development. In this study, we describe production of ZIKV E using the modified polyethyleneimine (PEI) transfection in HEK293 cells to improve cost-effective large-scale production.
View Article and Find Full Text PDFPrevious studies showed that mecamylamine a noncompetitive and nonspecific blocker of nicotinic acetylcholine receptors (nAChRs), stimulates the activity of the dorsal raphe nucleus (DRN) serotonergic neurons and DRN serotonin (5-HT) release. In the present study, the mechanisms involved in these mecamylamine-induced effects were examined using electrophysiology and calcium-imaging studies, both performed in Wistar rat midbrain slices. Mecamylamine (0.
View Article and Find Full Text PDFJ Cardiovasc Pharmacol Ther
November 2019
Statins may precipitate the onset of type 2 diabetes (T2D) in high-risk patients. In contrast, only the subset of individuals with insulin resistance and/or diabetes receives cardiovascular benefits with fibrates. In this context, previous observations from our laboratory suggested that atorvastatin induced an increase in visceral adipose tissue (VAT), whereas fenofibrate had the opposite effects in rabbits.
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