Ginsenoside Rb1 promotes neurotransmitter release by modulating phosphorylation of synapsins through a cAMP-dependent protein kinase pathway

• Published in: Brain research Vol. 1106; no. 1; pp. 91 - 98
• Main Authors: Xue, Jian-Fei, Liu, Zhi-Jun, Hu, Jin-Feng, Chen, Hong, Zhang, Jun-Tian, Chen, Nai-Hong
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 23.08.2006; Amsterdam Elsevier; New York, NY
• Subjects: Animals; Animals, Newborn; Araliaceae; Biological and medical sciences; Brain - drug effects; Brain - metabolism; Cyclic AMP - metabolism; Cyclic AMP-Dependent Protein Kinases - drug effects; Cyclic AMP-Dependent Protein Kinases - metabolism; Drugs, Chinese Herbal - pharmacology; Enzyme Inhibitors - pharmacology; General pharmacology; Ginsenosides - pharmacology; Male; Medical sciences; Neurotransmitter Agents - metabolism; Neurotransmitter Agents - secretion; Neurotransmitter release; Nootropic Agents - pharmacology; Panax ginseng; PC12 Cells; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Phosphorylation - drug effects; PKA; Presynaptic Terminals - drug effects; Presynaptic Terminals - metabolism; Presynaptic Terminals - secretion; Protein Structure, Tertiary - drug effects; Protein Structure, Tertiary - physiology; Rats; Rats, Sprague-Dawley; Rb1; Rg1; Signal Transduction - drug effects; Signal Transduction - physiology; Synapsin; Synapsins - drug effects; Synapsins - metabolism; Synaptic Transmission - drug effects; Synaptic Transmission - physiology; Synaptosomes; Up-Regulation - drug effects; Up-Regulation - physiology; Rb1; Neurotransmitter release; Synapsin; Rg1; PKA; Phosphorylation; Enzyme; Transferases; Oriental medicine; In vitro; Panax ginseng; Medicinal plant; Cell line; Folk medicine; Protein kinase; Dicotyledones; Angiospermae; Neurotransmitter; Spermatophyta; Araliaceae; Release
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/j.brainres.2006.05.106

Ginseng, the root of Panax ginseng C.A. Meyer (Araliaceae), has been extensively used in traditional oriental medicine for the prevention and treatment of aging-related disorders for over 2000 years. Accumulating evidence suggests that ginsenosides such as Rg1 and Rb1, which are the pharmacologically active ingredients of ginseng, modulate neurotransmission. Synapsins are abundant phosphoproteins essential for regulating neurotransmitter release. All synapsins contain a short amino-terminal domain A that is highly conserved and phosphorylated by cAMP-dependent protein kinase (PKA), which plays a key role in regulating neurotransmitter release. In the present study, we demonstrated that both Rg1 and Rb1 increased neurotransmitter release in undifferentiated and differentiated PC12 cells. However, in the presence of the PKA inhibitor H89, Rg1, but not Rb1, still induced neurotransmitter release. Moreover, Rb1, but not Rg1, enhanced the phosphorylation of synapsins via PKA pathway. In summary, Rb1 promotes neurotransmitter release by increasing the phosphorylation of synapsins through the PKA pathway, whereas the similar effects observed with Rg1 are independent of the phosphorylation of synapsins.