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Cellular Stress Responses Following Photodynamic Therapy
Published in Barbara W. Henderson, Thomas J. Dougherty, Photodynamic Therapy, 2020
Stefan W. Ryter, Charles J. Gomer, Angela Ferrario, Anita M. R. Fisher, Marian Luna, Natalie Rucker, Sam Wong
Heme oxygenase, a microsomal enzyme, catalyzes the oxidative degradation of heme to biliverdin, liberating the α-methene bridge carbon as carbon monoxide [25]. NADPH: biliverdin reductase completes heme catabolism by reducing biliverdin to bilirubin, which upon glucuronidation, passes from the body by the biliary-fecal route [20]. An antioxidant role has been suggested for heme oxygenase on the basis that bilirubin and biliverdin have plasma antioxidant (peroxyl radical scavenging) properties, though this probably has little in vitro significance [26].
Recent and Future Developments
Published in Giulio Fanti, Pierandrea Malfi, of Turin, 2019
Giulio Fanti, Pierandrea Malfi
Biliverdin is known as an oxidative ring cleavage product of the heme of blood. The Energy Dispersive Spectroscopy (EDS) of the sample confirms an elemental composition fully compatible with this hypothesis. So a high correlation between the vibrational frequencies of the micro-substance adhering to the Shroud fiber and those of blood derivatives (heme/biliverdin-derived compounds and protein traces, amide I) has been demonstrated.
Monitoring polycyclic aromatic compounds exposure in fish using biliary metabolites
Published in Critical Reviews in Environmental Science and Technology, 2022
Jamie M. Dearnley, Charles Killeen, Rebecca L. Davis, Vince P. Palace, Gregg T. Tomy
Quantitation of bile pigments has become a mandatory step in most modern PAC biliary analyses. When a fish feeds, its gall bladder is first emptied into the digestive tract and subsequently filled with dilute, watery bile. The gall bladder then begins accumulating PAC metabolites anew as they are processed by the liver, changing the density and volume of the bile until the cycle resets with the next feeding (Ariese et al., 1997; Collier & Varanasi, 1991). Consequently, feeding status can have a strong influence on the concentration of metabolites detected in a sample. To counteract this effect, quantitation of the bile pigment biliverdin has become commonplace (assays for protein content have also seen use; Couderc et al., 2015), against which PAC concentrations can be normalized. Biliverdin analysis is accomplished by diluting bile 100 times in a 50/50 mixture of ethanol/water and determining absorbance at 380 nm. Variations involving other wavelengths and dilution factors are also employed (Ariese et al., 1997; Nagel, Kammann, et al., 2012; Richardson et al., 2004). The method’s goal is to reduce variation, but it has had mixed results. In some instances the technique has reduced variability in the reported data set (Kammann, 2007; Nagel, Wagner, et al., 2012; Ruddock et al., 2003), in others it has not (Pathiratne et al., 2010; Vethaak et al., 2016; Vuorinen et al., 2006). Thus, measurement of bile pigment concentration continues to be recommended as part of sampling regimes, but decisions on whether to use the normalized or non-normalized data must be made situationally. Such normalization is particularly important in situations where significant differences in feeding status between different fish are known to exist.