Litsea japonica Extract Inhibits Aldose Reductase Activity and Hyperglycemia-Induced Lenticular Sorbitol Accumulation in dbdb Mice

Abstract EN

Aldose reductase (AR) is the first and rate-limiting enzyme of the polyol pathway.

AR-dependent synthesis of excess polyols leads to lens opacification in diabetic cataract.

The purpose of this study is to investigate the protective effect of Litsea japonica extract (LJE) on diabetes-induced lens opacification and its protective mechanism in db/db mice.

Seven-week-old male db/db mice were treated with LJE (100 and 250 mg/kg body weight) once a day orally for 12 weeks.

LJE dose dependently inhibited rat lens aldose reductase activity in vitro (IC50 = 13.53 ± 0.74 µg/mL).

In db/db mice, lens was slightly opacified, and lens fiber cells were swollen and ruptured.

In addition, lenticular sorbitol accumulation was increased in db/db mice.

However, the administration of LJE inhibited these lenticular sorbitol accumulation and lens architectural changes in db/db mice.

Our results suggest that LJE might be beneficial for the treatment of diabetes-induced lens opacification.

The ability of LJE to suppress lenticular sorbitol accumulation may be mediated by the inhibition of AR activity.