title: Neuronal growth on L- and D-cysteine self-assembled monolayers reveals neuronal chiral sensitivity.
abstract: Studying the interaction between neuronal cells and chiral molecules is fundamental for the design of novel biomaterials and drugs. Chirality influences all biological processes that involve intermolecular interaction. One common method used to study cellular interactions with different enantiomeric targets is the use of chiral surfaces. Based on previous studies that demonstrated the importance of cysteine in the nervous system, we studied the effect of L- and D-cysteine on single neuronal growth. L-Cysteine, which normally functions as a neuromodulator or a neuroprotective antioxidant, causes damage at elevated levels, which may occur post trauma. In this study, we grew adult neurons in culture enriched with L- and D-cysteine as free compounds or as self-assembled monolayers of chiral surfaces and examined the effect on the neuronal morphology and adhesion. Notably, we have found that exposure to the L-cysteine enantiomer inhibited, and even prevented, neuronal attachment more severely than exposure to the D-cysteine enantiomer. Atop the L-cysteine surfaces, neuronal growth was reduced and degenerated. Since the cysteine molecules were attached to the surface via the thiol groups, the neuronal membrane was exposed to the molecular chiral site. Thus, our results have demonstrated high neuronal chiral sensitivity, revealing chiral surfaces as indirect regulators of neuronal cells and providing a reference for studying chiral drugs.
authors.affiliation: Faculty of Engineering, ‡Department of Chemistry, §Gonda Multidisciplinary Brain Research Center, and ∥Bar Ilan Institute of Nanotechnologies and Advanced Materials, Bar Ilan University , 5290002 Ramat Gan, Israel.
authors.forename: Koby
authors.initials: K
authors.lastname: Baranes
authors.forename: Hagay
authors.initials: H
authors.lastname: Moshe
authors.forename: Noa
authors.initials: N
authors.lastname: Alon
authors.forename: Shmulik
authors.initials: S
authors.lastname: Schwartz
authors.forename: Orit
authors.initials: O
authors.lastname: Shefi
mesh_terms: D000327:Adsorption; D000818:Animals; D002478:Cells, Cultured; D003545:Cysteine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005724:Ganglia / Q000166:cytology; D007865:Leeches; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D008855:Microscopy, Electron, Scanning; D055495:Neurogenesis / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects* / Q000648:ultrastructure; D013237:Stereoisomerism; D013499:Surface Properties / Q000187:drug effects; D013997:Time Factors
chemical_list: D003545:Cysteine