Molecular neurobiology
-
Molecular neurobiology · Jul 2017
Hypothesizing Music Intervention Enhances Brain Functional Connectivity Involving Dopaminergic Recruitment: Common Neuro-correlates to Abusable Drugs.
The goal of this review is to explore the clinical significance of music listening on neuroplasticity and dopaminergic activation by understanding the role of music therapy in addictive behavior treatment. fMRI data has shown that music listening intensely modifies mesolimbic structural changes responsible for reward processing (e.g., nucleus accumbens [NAc]) and may control the emotional stimuli's effect on autonomic and physiological responses (e.g., hypothalamus). Music listening has been proven to induce the endorphinergic response blocked by naloxone, a common opioid antagonist. NAc opioid transmission is linked to the ventral tegmental area (VTA) dopamine release. ⋯ It has been found that musical training before the age of 7 results in changes in white-matter connectivity, protecting carriers with low dopaminergic function (DRD2A1 allele, etc.) from poor decision-making, reward dependence, and impulsivity. In this article, we briefly review a few studies on the neurochemical effects of music and propose that these findings are relevant to the positive clinical findings observed in the literature. We hypothesize that music intervention enhances brain white matter plasticity through dopaminergic recruitment and that more research is needed to explore the efficacy of these therapies.
-
Molecular neurobiology · Jul 2017
Inosine, an Endogenous Purine Nucleoside, Suppresses Immune Responses and Protects Mice from Experimental Autoimmune Encephalomyelitis: a Role for A2A Adenosine Receptor.
Multiple sclerosis (MS) is a T cell autoimmune, inflammatory, and demyelinating disease of the central nervous system (CNS). Currently available therapies have partially effective actions and numerous side reactions. Inosine, an endogenous purine nucleoside, has immunomodulatory, neuroprotective, and analgesic properties. ⋯ Furthermore, neuroinflammation and demyelinating processes were blocked by inosine treatment. Additionally, inosine consistently inhibited IL-17 levels in peripheral lymphoid tissue, as well as IL-4 levels and A2AR up-regulation in the spinal cord, likely, through an ERK1-independent pathway. EAE: experimental autoimmune encephalomyelitis; MS: multiple sclerosis; A2AR: adenosine A2A receptor; IL-17: interleukin-17; IL-4: interleukin-4.
-
Molecular neurobiology · Jul 2017
Metformin Improves Functional Recovery After Spinal Cord Injury via Autophagy Flux Stimulation.
Spinal cord injury (SCI) is a severe neurological disease with few efficacious drugs. Autophagy is a cellular process to confront with stress after SCI and considered to be a therapeutic target of SCI. In this study, we investigated the therapeutic effect of metformin on functional recovery after SCI and its underlying mechanism of autophagy regulation. ⋯ Blockage of autophagy flux by chloroquine partially abolished the apoptosis inhibition and functional recovery effect of metformin on SCI, which suggested that the protective effect of metformin on SCI was through autophagy flux stimulation. Activation of AMPK as well as inhibition of its downstream mTOR signaling were detected under metformin treatment in vivo and in vitro; inhibition of AMPK signaling by compound C suppressed autophagy flux induced by metformin in vitro, indicating that AMPK signaling was involved in the effect of metformin on autophagy flux regulation. Together, these results illustrated that metformin improved functional recovery effect through autophagy flux stimulation and implied metformin to be a potential drug for SCI therapy.
-
Molecular neurobiology · Jul 2017
Guanosine Exerts Neuroprotective Effect in an Experimental Model of Acute Ammonia Intoxication.
The nucleoside guanosine (GUO) increases glutamate uptake by astrocytes and acts as antioxidant, thereby providing neuroprotection against glutamatergic excitotoxicity, as we have recently demonstrated in an animal model of chronic hepatic encephalopathy. Here, we investigated the neuroprotective effect of GUO in an acute ammonia intoxication model. Adult male Wistar rats received an intraperitoneal (i.p.) injection of vehicle or GUO 60 mg/kg, followed 20 min later by an i.p. injection of vehicle or 550 mg/kg of ammonium acetate. ⋯ GUO drastically reduced the lethality rate and the duration of coma. Animals treated with GUO had improved EEG traces, decreased CSF levels of glutamate and alanine, lowered oxidative stress in the cerebral cortex, and increased glutamate uptake by astrocytes in brain slices compared with animals that received vehicle prior to ammonium acetate administration. This study provides new evidence on mechanisms of guanine-derived purines in their potential modulation of glutamatergic system, contributing to GUO neuroprotective effects in a rodent model of by acute ammonia intoxication.
-
Molecular neurobiology · Jul 2017
Repeated Neonatal Sevoflurane Exposure-Induced Developmental Delays of Parvalbumin Interneurons and Cognitive Impairments Are Reversed by Environmental Enrichment.
Parvalbumin (PV) interneurons are critically involved in the cognitive processes. Based on prior investigations that environmental enrichment reverses impaired cognition after anesthetic exposure, we proposed that environmental enrichment protects PV interneurons and thereby improves sevoflurane-induced cognitive impairments. Six-day-old C57BL/6 male mice were exposed to 3 % sevoflurane or 30 % oxygen/air 2 h daily for 3 days from postnatal day 6 (P6) to P8. ⋯ The sevoflurane-exposed mice that were placed in an enriched environment exhibited normal behavior and had PV interneurons that did not differ from those in the control mice at P42-43. Neonatal sevoflurane exposure induces a reduced freezing response in the contextual test at P43 and developmental delays in PV interneurons in the prefrontal cortex and hippocampus. Placement of the sevoflurane-exposed mice in an enriched environment can prevent these abnormalities.