Journal: International Journal of Molecular Sciences

Article Title: Characterization of Inhibitory Capability on Hyperpolarization-Activated Cation Current Caused by Lutein (β,ε-Carotene-3,3′-Diol), a Dietary Xanthophyll Carotenoid

doi: 10.3390/ijms23137186

Figure Lengend Snippet: Comparisons among effects of lutein, lutein plus oxaliplatin, and lutein plus ivabradine on I h amplitude recorded from GH 3 cells. In these experiments, whole-cell current recordings were performed in cells immersed in Ca 2+ -free, Tyrode’s solution containing 1 μM TTX, and during the measurements, we filled up the recording pipette with K + -enriched internals solution. ( A ) Superimposed current traces acquired in the control period (a, black color) and during cell exposure to 3 μM lutein-alone (b, red color) or to 3 μM lutein plus 10 μM oxaliplatin (OXAL) (c, brown color). The upper part denotes the voltage protocol (blue color) imposed on the tested cell. ( B ) Summary scatter graph demonstrating the effect of lutein, lutein plus oxaliplatin (OXAL), and lutein plus ivabradine on I h amplitude (mean ± SEM; n = 7 for each point). We measured each current amplitude (acquired during cell exposure to different tested compounds) at the end-point of the 2-sec hyperpolarizing step from −40 to −120 mV. In the experiments on lutein plus OXAL or lutein or ivabradine, lutein was first added to the bath before OXAL or ivabradine was further applied. * Significantly different from control ( p < 0.05) and **significantly different from the lutein-alone (3 μM) group ( p < 0.05).

Article Snippet: Lutein (xanthophyll, Yè huáng sù, β,ε-carotene-3,3′-diol, 3,3′-di-hydroxy-β,ε-carotene, (1R)-4-[(1E,3E,5E,7E,9E,11E,13E,15E,17E)-18-[(1R,4R)-4-hydroxy-2,6,6-trimethylcyclohex-2-en-1-yl]-3,7,12,16-tetramethyloctadeca-1,3,5,7,9,11,13,15,17-nonaenyl]-3,5,5-trimethylcyclohex-3-en-1-ol, CID 5281243, C40H56O2, https://pubchem.ncbi.nlm.nih.gov/compound/5281243 ) (accessed on 1 June 2022) was acquired from MedChemExpress (Genechain, Kaohsiung, Taiwan), while ivabradine, oxaliplatin and tetrodotoxin (TTX) were from Sigma-Aldrich (St. Louis, MO).

Techniques: Transferring, Control

Journal: International Journal of Molecular Sciences

Article Title: Characterization of Inhibitory Capability on Hyperpolarization-Activated Cation Current Caused by Lutein (β,ε-Carotene-3,3′-Diol), a Dietary Xanthophyll Carotenoid

doi: 10.3390/ijms23137186

Figure Lengend Snippet: Modification by lutein on the strength in voltage-dependent hysteresis (Hys (V) ) of I h recorded from GH 3 cells. ( A ) Representative Hys (V) traces (i.e., the relationship of forward [descending] or reverse [ascending] current versus membrane potential) of I h evoked by the inverted double (i.e., isosceles-triangular) V ramp (indicated in the top part, blue color) in the absence (black color, a) or presence of 3 μM lutein (red color, b). The dashed black arrows along the current trace in the control period (i.e., lutein was not present) indicate an anti-clockwise direction of I h trajectory in which time passes with the activation by inverted triangular V ramp , while the shaded region is the Hys (V) area (∆area) with or without the lutein existence. ( B ) Summary graph revealing effects of lutein (1 or 3 μM) and lutein (3 μM) plus ivabradine (3 μM) on the ∆area of Hys (V) (i.e., the shaded region under the curve activated during the downsloping and upsloping ends of triangular V ramp ) of I h (mean ± SEM; n = 7 for each point). Of note, there was an emergence of V ramp -induced Hys (V) for I h elicitation, and the presence of lutein was concentration-dependently able to produce a measurable reduction in the Hys (V) ’s ∆area of the current. * Significantly different from control ( p < 0.05) and ** significantly different from lutein-alone (3 μM) group ( p < 0.05).

Article Snippet: Lutein (xanthophyll, Yè huáng sù, β,ε-carotene-3,3′-diol, 3,3′-di-hydroxy-β,ε-carotene, (1R)-4-[(1E,3E,5E,7E,9E,11E,13E,15E,17E)-18-[(1R,4R)-4-hydroxy-2,6,6-trimethylcyclohex-2-en-1-yl]-3,7,12,16-tetramethyloctadeca-1,3,5,7,9,11,13,15,17-nonaenyl]-3,5,5-trimethylcyclohex-3-en-1-ol, CID 5281243, C40H56O2, https://pubchem.ncbi.nlm.nih.gov/compound/5281243 ) (accessed on 1 June 2022) was acquired from MedChemExpress (Genechain, Kaohsiung, Taiwan), while ivabradine, oxaliplatin and tetrodotoxin (TTX) were from Sigma-Aldrich (St. Louis, MO).

Techniques: Modification, Membrane, Control, Activation Assay, Concentration Assay