Inhibitory effects of fidarestat on aldose reductase and aldehyde reductase activity evaluated by a new method using HPLC with post-column spectrophotometric detection
K. Mizuno et al., Inhibitory effects of fidarestat on aldose reductase and aldehyde reductase activity evaluated by a new method using HPLC with post-column spectrophotometric detection, BIOL PHAR B, 23(2), 2000, pp. 244-248
A new method to assay the activity of aldose reductase (AR) and aldehyde re
ductase (AHR) by high-performance liquid chromatography is described. The s
eparation of AR and AHR from tissue extracts using an anion-exchange column
was followed by chromatographic measurement of the activity in the elute.
AR and AHR activity were expressed as the area under the peak obtained by p
ost-column spectrophotometric detection of the decrease of coenzyme (NADPH)
in each enzyme reaction. In the enzyme preparation from rat or human tissu
es obtained bg this method, two active peaks were identified as AR and AHR,
The correlation coefficient between the injection volume of the enzyme pre
paration from each tissue and each peak area was 0.998 or greater. In addit
ion, the within-day preservation rate of AR or AHR activity from each tissu
e was over 95%.
In a comparative study of fidarestat with other AR inhibitors using this me
thod, it was confirmed that the inhibitory effect of fidarestat on AR activ
ity from each rat tissue was more potent than that produced by sorbinil and
equipotent to that of epalrestat and zenarestat, Fidarestat was also found
to inhibit AR activity more potently than AHR activity in human erythrocyt
es. Therefore, this method is applicable to studies of the selective inhibi
tion of AR or AHR by test compounds.