Superoxide anion concentration, as detected with coelenterazine, serves as an <i>in vivo</i> reporter of beta-cell mass.

<p>(A) Images of a representative nonprogressive mouse at 10, 12, 14 and 16 weeks of age. (B) Images of a representative progressive mouse at 10, 12, 14 and 16 weeks of age. The progressive mouse was normoglycemic at the time of the images. (C) The signal intensities for the two groups of mice, nonprogressive (white) (n = 8) and progressive (black) (n = 7), for a given age normalized to the first day of imaging for the corresponding mouse and expressed as the fold change in signal intensity. (D) The signal intensities for the nonprogressive mice during the last week of the study normalized to the first day of imaging for the corresponding mouse and expressed as the fold change in signal intensity. The signal intensities for progressive mice for the last day of the study during which their fasting blood glucose levels were not exceeding 5.6, 6.9 or 8.3 mmol/L normalized to the first day of imaging for the corresponding mouse and expressed as the fold change in signal intensity. (E) The mean of the fasting blood glucose levels that were less than 8.3 mmol/L for nonprogressive and progressive mice. (Error bars represent the mean ± SEM, and * denotes a significant difference between the groups of P < 0.039.)</p

HeLa cells produce coelenterazine chemiluminescence <i>in vitro</i>.

<p>(A) 5x10⁵ HeLa cells were imaged sequentially, at 5 min intervals for 1 hour. (B) Quantification of HeLa (black) or buffer (white) coelenterazine chemiluminescence at each time point (n = 3). (C) 5x10⁵ HeLa cells were imaged at 15 minutes following the addition of native coelenterazine ranging in concentration from 0 μmol/L to 100 μmol/L. (D) Quantification of HeLa (black) or buffer (white) coelenterazine chemiluminescence (n = 3). (E) A range of 500 to 1x10⁶ HeLa cells were imaged 15 minutes following the addition of 10 μmol/L of native coelenterazine. (F) A range of 500 to 1x10⁶ HeLa cells were imaged 1 minute following the addition of 1.07 mmol/L luciferin. (G) Correlation graph of coelenterazine chemiluminescent signal intensity (y-axis) versus the corresponding luciferase signal intensity (x-axis) for a given cell concentration. (Error bars represent the mean ± SEM.)</p

Treatment with mitochondrial shuttle inhibitors, GKA50, Ranolazine and glucose results in significant decreases in superoxide concentration as detected by coelenterazine chemiluminescence.

<p>(A) Bold, red font indicates methods of perturbation. The physiological response of cells was assessed by addition of glucose, GKA50, an activator of glycolysis, AOAC, an inhibitor of the malate-aspartate shuttle, 4-OHCA, an inhibitor of the pyruvate and lactate shuttle, ranolazine, an inhibitor of beta-oxidation and an activator of pyruvate dehydrogenase. (B) HeLa cells were treated with vehicle control, 250 μmol/L of 4-OHCA, 100 μmol/L AOAC, a combination of 4-OHCA and AOAC, 1 μmol/L GKA50 or 1 μmol/L Ranolazine and the final glucose concentrations adjusted from 4 mmol/L to 4 mmol/L, 11.7 mmol/L or 30 mmol/L and sequentially imaged. Representative image is 95 minutes post treatment. (C) Quantification of coelenterazine chemiluminescence 95 minutes post-treatment (n = 3). (Error bars represent the mean ± SEM, * denotes a significant difference from the 4 mmol/L control of P < 0.05, # denotes a significant difference from the 11.7 mmol/L control of P < 0.015, and + denotes a significant difference from the 30 mmol/L control of P < 0.015.)</p

Coelenterazine chemiluminescence is dependent upon superoxide anion concentrations <i>in vitro</i>.

<p>(A) HeLa cells were treated with range of 0 units/mL to 300 units/mL of PEG-SOD and imaged sequentially. The image was taken at 95 minutes post PEG-SOD addition. (B) Quantification of HeLa (black) or buffer (white) coelenterazine chemiluminescence for each concentration 95 minutes post PEG-SOD addition (n = 3). (C) HeLa cells were treated with range of 0 units/mL to 600 units/mL of PEG-CAT and imaged sequentially. Image is 95 minutes post PEG-CAT addition. (D) Quantification of HeLa (black) or buffer (white) coelenterazine chemiluminescence for each concentration 95 minutes post PEG-CAT addition (n = 3). (E) HeLa cells were treated with range of 0 μmol/L to 500 μmol/L of uric acid and imaged sequentially. Image is 95 minutes post uric acid addition. (F) Quantification of HeLa (black) or buffer (white) coelenterazine chemiluminescence for each concentration 95 minutes post uric acid addition (n = 3). (Error bars represent the mean ± SEM, and * denotes significant differences of P < 0.02.)</p