Chlorogenic acid alters the voltage-gated potassium channel currents of trigeminal ganglion neurons.
Chlorogenic acid (5-caffeoylquinic acid, CGA) is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to its notable biological functions against cardiovascular diseases, type-2 diabetes and inflammatory conditions, CGA was recently hypothesized to be an alternative for the treatment of neurological diseases such as Alzheimer's disease and neuropathic pain disorders. However, its mechanism of action is unclear. Voltage-gated potassium channel (Kv) is a crucial factor in the electro-physiological processes of sensory neurons. Kv has also been identified as a potential therapeutic target for inflammation and neuropathic pain disorders. In this study, we analysed the effects of CGA on the two main subtypes of Kv in trigeminal ganglion neurons, namely, the IK,A and IK,V channels. Trigeminal ganglion (TRG) neurons were acutely disassociated from the rat TRG, and two different doses of CGA (0.2 and 1 mmol⋅L(-1)) were applied to the cells. Whole-cell patch-clamp recordings were performed to observe alterations in the activation and inactivation properties of the IK,A and IK,V channels. The results demonstrated that 0.2 mmol⋅L(-1) CGA decreased the peak current density of IK,A. Both 0.2 mmol⋅L(-1) and 1 mmol⋅L(-1) CGA also caused a significant reduction in the activation and inactivation thresholds of IK,A and IK,V. CGA exhibited a strong effect on the activation and inactivation velocities of IK,A and IK,V. These findings provide novel evidence explaining the biological effects of CGA, especially regarding its neurological effects.
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Yu-Jiao
YJ
Zhang
Ningbo Dental Hospital, Ningbo, China.
Xiao-Wen
XW
Lu
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Ning
N
Song
Ningbo Dental Hospital, Ningbo, China.
Liang
L
Kou
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Min-Ke
MK
Wu
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Fei
F
Liu
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Hang
H
Wang
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Jie-Fei
JF
Shen
D000700:Analgesics / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D018929:Cell Culture Techniques; D002726:Chlorogenic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D015640:Ion Channel Gating / Q000187:drug effects; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D018377:Neurotransmitter Agents / Q000008:administration & dosage / Q000494:pharmacology*; D018408:Patch-Clamp Techniques; D024642:Potassium Channels, Voltage-Gated / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012668:Trigeminal Ganglion / Q000187:drug effects*
D000700:Analgesics; D018377:Neurotransmitter Agents; D024642:Potassium Channels, Voltage-Gated; D002726:Chlorogenic Acid