mGlu5 play an important role in physiology and pathology to various central nervous system (CNS) diseases. Several positron emission tomography (PET) radiotracers have been developed to explore the role of mGlu5 in brain disorders. However, there are no single photon emission computed tomography (SPECT) radioligands for mGlu5. Here we report development of [(123)I]IPEB ([(123)I]1) and [(123)I]IMPEB ([(123)I]2) as mGlu5 radioligands for SPECT. [(123)I]1 and [(123)I]2 were produced by copper(I) mediated aromatic halide displacement reactions.
To explore acute and long-term effects of 3-nitropropionic acid (3-NP)-induced neurotoxicity, longitudinal positron emission tomography (PET) studies of energy metabolism and magnetic resonance spectroscopic (MRS) studies of neurochemicals were conducted in a rat model. The first injection of 3-NP (20 mg/kg i.p.) was followed by MRS study of neurochemicals and PET study of glucose utilization using [(18)F]2-fluorodeoxy-D-glucose ((18)F-FDG). After that, 3-NP administration was done two times a day with a dose of 10 mg/kg i.p.
Viral oncolysis, the destruction of cancer cells by replicating virus, is an experimental cancer therapy that continues to be explored. The treatment paradigm for this therapy involves successive waves of lytic replication in cancer cells. At present, monitoring viral titer at sites of replication requires biopsy. However, repeat serial biopsies are not practically feasible for temporal monitoring of viral replication and tumor response in patients. Molecular imaging provides a noninvasive method to identify intracellular viral gene expression in real time.
Viral oncolysis, the destruction of cancer cells by replicating viruses, is under clinical investigation for cancer therapy. Lytic viral replication in cancer cells both destroys the cells and liberates progeny virion to infect adjacent cancer cells. The safety and efficacy of this approach are dependent on selective and robust viral replication in cancer cells rather than in normal cells. Methods to detect and quantify viral replication in tissues have relied on organ sampling for molecular analyses.
Insulin resistance is an increasingly prevalent condition in humans that frequently clusters with disorders characterized by left ventricular (LV) pressure overload, such as systemic hypertension. To investigate the impact of insulin resistance on LV remodeling and functional response to pressure overload, C57BL6 male mice were fed a high-fat (HFD) or a standard diet (SD) for 9 days and then underwent transverse aortic constriction (TAC). LV size and function were assessed in SD- and HFD-fed mice using serial echocardiography before and 7, 21, and 28 days after TAC.
The insulin-sensitive isoform of the glucose transporting protein, Glut4, is expressed in fat as well as in skeletal and cardiac muscle and is responsible for the effect of insulin on blood glucose clearance. Recent studies have revealed that Glut4 is also expressed in the brain, although the intracellular compartmentalization and regulation of Glut4 in neurons remains unknown.
PURPOSE: The lipophilic cationic compound, (4-[¹⁸F]fluorophenyl)triphenylphosphonium ion (¹⁸F-FTPP) was synthesized and evaluated as a potential positron emission tomography (PET) myocardial perfusion agent.
Pharmacologic or genetic blockade of metabotropic glutamate mGlu5 receptors (mGluR5) has been shown to attenuate parkinsonian motor deficits and protect nigrostriatal neurons from damage in the acute MPTP model of Parkinson's disease (PD), suggesting that therapeutically targeting the mGluR5 receptor may offer a novel approach to improving motor symptoms and/or slowing neurodegeneration in PD. This study further explored the neuroprotective potential of targeting mGluR5 receptors.
It has been hypothesized that neuroinflammation triggered during brain development can alter brain functions later in life. We investigated the contribution of inflammation to the alteration of normal brain circuitries in the context of neuroexcitotoxicity following neonatal ventral hippocampal lesions in rats with ibotenic acid, an NMDA glutamate receptor agonist. Excitotoxic ibotenic acid lesions led to a significant and persistent astrogliosis and microglial activation, associated with the production of inflammatory mediators.
UNLABELLED: Degeneration of dopaminergic neurons of the substantia nigra pars compacta is a cardinal feature of Parkinson's disease (PD). Although uncertain, the pathology has been suggested to derive from a malfunction of the complex interaction between dopaminergic and metabotropic glutamate receptors (mGluRs). To further address this issue, we investigated the imaging profile and expression of dopamine D(2) receptors and mGluRs in a classic parkinsonian rodent model induced by the toxin 6-hydroxydopamine.
