title: Neurite outgrowth stimulatory effects of myco synthesized AuNPs from Hericium erinaceus (Bull.: Fr.) Pers. on pheochromocytoma (PC-12) cells.
abstract: BACKGROUND
  Hericium erinaceus has been reported to have a wide range of medicinal properties such as stimulation of neurite outgrowth, promotion of functional recovery of axonotmetic peroneal nerve injury, antioxidant, antihypertensive, and antidiabetic properties. In recent years, the green synthesis of gold nanoparticles (AuNPs) has attracted intense interest due to the potential use in biomedical applications. The aim of this study was to investigate the effects of AuNPs from aqueous extract of H. erinaceus on neurite outgrowth of rat pheochromocytoma (PC-12) cells.
  
  
  METHODS
  The formation of AuNPs was characterized by UV-visible spectrum, energy dispersive X-ray (EDX), field-emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), particle size distribution, and Fourier transform-infrared spectroscopy (FTIR). Furthermore, the neurite extension study of synthesized AuNPs was evaluated by in vitro assay.
  
  
  RESULTS
  The AuNPs exhibited maximum absorbance between 510 and 600 nm in UV-visible spectrum. FESEM and TEM images showed the existence of nanoparticles with sizes of 20-40 nm. FTIR measurements were carried out to identify the possible biomolecules responsible for capping and efficient stabilization of the nanoparticles. The purity and the crystalline properties were confirmed by EDX diffraction analysis, which showed strong signals with energy peaks in the range of 2-2.4 keV, indicating the existence of gold atoms. The synthesized AuNPs showed significant neurite extension on PC-12 cells. Nerve growth factor 50 ng/mL was used as a positive control. Treatment with different concentrations (nanograms) of AuNPs resulted in neuronal differentiation and neuronal elongation. AuNPs induced maximum neurite outgrowth of 13% at 600 ng/mL concentration.
  
  
  CONCLUSIONS
  In this study, the AuNPs synthesis was achieved by a simple, low-cost, and rapid bioreduction approach. AuNPs were shown to have potential neuronal differentiation and stimulated neurite outgrowth. The water-soluble bioconstituents could be responsible for the neuroactivity. This is the first report for the biosynthesis of AuNPs using the hot aqueous extract of H. erinaceus.
authors.affiliation: Mushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Jegadeesh
authors.initials: J
authors.lastname: Raman
authors.affiliation: Mushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Hariprasath
authors.initials: H
authors.lastname: Lakshmanan
authors.affiliation: Mushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia ; Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Priscilla A
authors.initials: PA
authors.lastname: John
authors.affiliation: Low Dimensional Materials Research Center (LDMRC), Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Chan
authors.initials: C
authors.lastname: Zhijian
authors.affiliation: Low Dimensional Materials Research Center (LDMRC), Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Vengadesh
authors.initials: V
authors.lastname: Periasamy
authors.affiliation: Mushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia ; Department of Anatomy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Pamela
authors.initials: P
authors.lastname: David
authors.affiliation: Mushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia ; Department of Anatomy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Murali
authors.initials: M
authors.lastname: Naidu
authors.affiliation: Mushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia ; Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Vikineswary
authors.initials: V
authors.lastname: Sabaratnam
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000188:drug therapy*; D000818:Animals; D001487:Basidiomycota / Q000737:chemistry*; D005455:Fluorescent Antibody Technique; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000008:administration & dosage / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D016501:Neurites / Q000187:drug effects*; D016716:PC12 Cells; D010316:Particle Size; D010673:Pheochromocytoma / Q000188:drug therapy*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D010936:Plant Extracts; D006046:Gold
keywords: AuNPs; Hericium erinaceus; PC-12; nanoparticles; neurite outgrowth