title: Novel peptide VIP-TAT with higher affinity for PAC1 inhibited scopolamine induced amnesia.
abstract: A novel peptide VIP-TAT with a cell penetrating peptide TAT at the C-terminus of VIP was constructed and prepared using intein mediated purification with an affinity chitin-binding tag (IMPACT) system to enhance the brain uptake efficiency for the medical application in central nervous system. It was found by labeling VIP-TAT and VIP with fluorescein isothiocyanate (FITC) that the extension with TAT increased the brain uptake efficiency of VIP-TAT significantly. Then short-term and long-term treatment with scopolamine (Scop) was used to evaluate the effect of VIP-TAT or VIP on Scop induced amnesia. Both short-term and long-term administration of VIP-TAT inhibited the latent time reduction in step-through test induced by Scop significantly, but long-term administration of VIP aggravated the Scop induced amnesia. Long-term i.p. injection of VIP-TAT was shown to have positive effect by inhibiting the oxidative damage, apoptosis and the cholinergic system activity reduction that induced by Scop, while VIP exerted negative effect in brain opposite to that in periphery system. The in vitro data showed that VIP-TAT had not only protective but also proliferative effect on Neuro2a cells which was inhibited by PAC1 antagonist PACAP(6-38). Competition binding assay and cAMP assay confirmed that VIP-TAT had higher affinity and activation for PAC1 than VIP. So it was concluded that the significantly stronger protective effect of VIP-TAT against Scop induced amnesia than VIP was due to (1) the enhanced brain uptake efficiency of VIP-TAT and (2) the increased affinity and activation of VIP-TAT for receptor PAC1.
authors.affiliation: Cell Biology Institute, Department of Cell Biology, Jinan University, Guangzhou 510632, China. Electronic address: rongjie_yu1123@163.com.
authors.forename: Rongjie
authors.initials: R
authors.lastname: Yu
authors.affiliation: Cell Biology Institute, Department of Cell Biology, Jinan University, Guangzhou 510632, China.
authors.forename: Yanxu
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Cell Biology Institute, Department of Cell Biology, Jinan University, Guangzhou 510632, China.
authors.forename: Zekai
authors.initials: Z
authors.lastname: Cui
authors.affiliation: Cell Biology Institute, Department of Cell Biology, Jinan University, Guangzhou 510632, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Cell Biology Institute, Department of Cell Biology, Jinan University, Guangzhou 510632, China.
authors.forename: Zhixing
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Laboratory of Medical Genetics of Guangdong Medical College, Dongguan, Guangdong 523808, China.
authors.forename: Huahua
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000647:Amnesia / Q000139:chemically induced / Q000188:drug therapy*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D016466:CHO Cells; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010446:Peptide Fragments / Q000494:pharmacology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000494:pharmacology; D051239:Receptors, Vasoactive Intestinal Peptide, Type II / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D012601:Scopolamine / Q000037:antagonists & inhibitors*; D013329:Structure-Activity Relationship; D014660:Vasoactive Intestinal Peptide / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D010446:Peptide Fragments; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051239:Receptors, Vasoactive Intestinal Peptide, Type II; D011993:Recombinant Fusion Proteins; C000598411:VIP-TAT peptide; C075647:pituitary adenylate-cyclase-activating-peptide (6-38); D054322:tat Gene Products, Human Immunodeficiency Virus; D014660:Vasoactive Intestinal Peptide; D012601:Scopolamine
keywords: Amnesia; Neuro2a; PAC1; Scopolamine; VIP-TAT