Goodyschle A, a new butenolide with significant BchE inhibitory activity from Goodyera schlechtendaliana.

Goodyschle A (1), a new butenolide, was isolated from the whole grass of Goodyera schlechtendaliana, an orchidaceous edible medicinal plant. The structure of the new compound was elucidated by 1 D and 2 D NMR experiments in addition to HRESIMS analyses. Compound 1 was evaluated for its bioactivities including cytotoxic activity against human gastric cancer (SGC-7901) and human hepatocellular carcinoma (HepG2) cell lines, inhibitory activity on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), and DPPH radical scavenging activity. As a result, compound 1 showed potent BChE inhibitory activity (IC50 value = 6.88 ± 1.63 µM), moderate DPPH radical scavenging activity (IC50 value = 16.25 ± 0.21 µM), and slight AChE inhibitory and cytotoxic activities. These findings suggest that compound 1 is worthy for further investigations in terms of its selective BChE inhibitory activity.

Inhibitory effect of gallic acid on voltage-gated Na+ channels in rat cardiomyocytes.

Gallic acid (GA) has a protective effect on the cardiovascular system. To study its cardiac electrophysiological effects, voltage-gated Na+ channel currents (INa ) were recorded in rat cardiomyocytes using whole-cell patch clamp techniques. Moreover, the effects of GA on aconitine-induced arrhythmias were assessed using electrocardiograms in vivo. We found that the current-voltage characteristic curve (I-V curve) of INa significantly shifted in the presence of 1, 3, and 10 µmol/L of GA. The peak sodium current density (INa -Peak) was reduced from -84.02 ± 5.68 pA/pF to -65.78 ± 3.96 pA/pF with 1 µmol/L, -54.45 ± 5.18 pA/pF with 3 µmol/L, and -44.20 ± 4.35 pA/pF with 10 µmol/L, respectively. GA shifted the steady-state activation curve of INa and recovery curve to the right and the steady-state inactivation curve to the left. The observed inhibitory effect was comparable to that of amiodarone. GA pre-treatment significantly prolonged the onset of fatal ventricular fibrillation. Our results indicated that GA inhibited INa in rat ventricular myocytes and aconitine-induced arrhythmias in vivo. These results suggest the potential of GA for development as a novel anti-arrhythmic therapeutic.