Aldose reductase inhibitor for delaying galactose-induced cataract formation in wistar rats by isolated and characterized natural products from <i>Cuscuta reflexa</i>

Cataract blindness is a worldwide problem with no effective treatment. It has increased interest in natural cataract treatments. The ability of bioactive fractions of <i>Cuscuta reflexa</i> (CR) to inhibit aldose reductase (AR) and reduce galactose-induced cataracts in Wistar rats was tested, and the chemical was identified. AR inhibiters may slow cataract development. A LC-MS study characterised the hydroalcoholic extract of CR (HAECR). Rat lens homogenates were used to investigate AR inhibitory activity <i>in vivo</i>, focussing on HAECR's purified fractions (F1, F2, F3). Rats were given saline, galactose, galactose with quercetin, or galactose with fractions for 28 days. Animals were slaughtered and lenses were retrieved and homogenised to assess AR inhibitory action, photographic evidence, and oxidative stress. CR fractions inhibited AR activity, with F2 being the most powerful of the three. Pure F2 yielded compound C1, which was structurally identified as gitoxigenin.