title: High resolution 1H NMR-based metabonomic study of the auditory cortex analogue of developing chick (Gallus gallus domesticus) following prenatal chronic loud music and noise exposure.
abstract: Proper functional development of the auditory cortex (ACx) critically depends on early relevant sensory experiences. Exposure to high intensity noise (industrial/traffic) and music, a current public health concern, may disrupt the proper development of the ACx and associated behavior. The biochemical mechanisms associated with such activity dependent changes during development are poorly understood. Here we report the effects of prenatal chronic (last 10 days of incubation), 110dB sound pressure level (SPL) music and noise exposure on metabolic profile of the auditory cortex analogue/field L (AuL) in domestic chicks. Perchloric acid extracts of AuL of post hatch day 1 chicks from control, music and noise groups were subjected to high resolution (700MHz) (1)H NMR spectroscopy. Multivariate regression analysis of the concentration data of 18 metabolites revealed a significant class separation between control and loud sound exposed groups, indicating a metabolic perturbation. Comparison of absolute concentration of metabolites showed that overstimulation with loud sound, independent of spectral characteristics (music or noise) led to extensive usage of major energy metabolites, e.g., glucose, β-hydroxybutyrate and ATP. On the other hand, high glutamine levels and sustained levels of neuromodulators and alternate energy sources, e.g., creatine, ascorbate and lactate indicated a systems restorative measure in a condition of neuronal hyperactivity. At the same time, decreased aspartate and taurine levels in the noise group suggested a differential impact of prenatal chronic loud noise over music exposure. Thus prenatal exposure to loud sound especially noise alters the metabolic activity in the AuL which in turn can affect the functional development and later auditory associated behaviour.
authors: Department of Anatomy, All India Institute of Medical Sciences, New Delhi 110029, India.
authors: Vivek
authors: V
authors: Kumar
authors: Department of Anatomy, All India Institute of Medical Sciences, New Delhi 110029, India. Electronic address: tapas_nag@yahoo.com.
authors: Tapas Chandra
authors: TC
authors: Nag
authors: Department of NMR and MRI Facility, All India Institute of Medical Sciences, New Delhi 110029, India.
authors: Uma
authors: U
authors: Sharma
authors: Department of NMR and MRI Facility, All India Institute of Medical Sciences, New Delhi 110029, India.
authors: Sujeet
authors: S
authors: Mewar
authors: Department of NMR and MRI Facility, All India Institute of Medical Sciences, New Delhi 110029, India.
authors: Naranamangalam R
authors: NR
authors: Jagannathan
authors: Department of Anatomy, All India Institute of Medical Sciences, New Delhi 110029, India.
authors: Shashi
authors: S
authors: Wadhwa
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000378:metabolism*; D002642:Chick Embryo; D005260:Female; D018811:Maternal Exposure; D055432:Metabolomics; D009146:Music; D009622:Noise; D011247:Pregnancy; D066244:Proton Magnetic Resonance Spectroscopy
keywords: Auditory cortex; Avian; Field L; Metabolite; NMR; Noise