JOURNAL ARTICLE

Klotho modulates electrical activity and calcium homeostasis in pulmonary vein cardiomyocytes via PI3K/Akt signalling

Yuan Hung, Yao-Chang Chen, Shih-Yu Huang, Yen-Yu Lu, Yung-Kuo Lin, Yu-Hsun Kao, Wei-Shiang Lin, Shih-Ann Chen, Yi-Jen Chen
Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology 2020 July 1, 22 (7): 1132-1141
32627831

AIMS: Klotho, a potential antiageing protein has remarkable cardiovascular effects, which is lower in the patients with chronic kidney disease (CKD). Chronic kidney disease increases the risk of atrial fibrillation, majorly triggered by pulmonary vein (PV) arrhythmogenesis. This study investigated whether klotho protein can modulate PV electrical activity and the underlying potential mechanisms.

METHODS AND RESULTS: A conventional microelectrode and whole-cell patch clamp were used to investigate the action potentials and ionic currents in isolated rabbit PV tissue preparations and single cardiomyocytes before and after klotho administration. Phosphoinositide 3-kinase (PI3K)/Akt signalling was studied using western blotting. Klotho significantly reduced PV spontaneous beating rates in PV tissue preparations at 1.0 and 3.0 ng/mL (but not at 0.1 and 0.3 ng/mL). In the presence of the Akt inhibitor (10 µM), klotho (1.0 and 3.0 ng/mL) did not change PV electrical activities. Klotho (1.0 ng/mL) significantly decreased the late sodium current (INa-Late) and L-type calcium current (ICa-L), similar to the Akt inhibitor (10 µM). Western blots demonstrated that klotho (1.0 ng/mL)-treated PV cardiomyocytes had less phosphorylation of Akt (Ser473) compared with klotho-untreated cardiomyocytes. Compared with control PVs, klotho at relatively lower concentrations (0.1 and 0.3 ng/mL) significantly reduced beating rates and decreased the amplitudes of delay afterdepolarizations in CKD PVs.

CONCLUSION: Klotho modulated PV electrical activity by inhibiting PI3K/Akt signalling, which may provide a novel insight into CKD-induced arrhythmogenesis.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
32627831
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"