Diosmin is a flavonoid found in a variety of citrus fruits and also an agonist of the aryl hydrocarbon receptor (AhR).
Treatment with Diosmin causes a dose dependent increase in the amount of adducts formed (up to a 7-fold increase in adducts at 5 μM Diosmin). At 5 μM, Diosmin increases the cytotoxicity of 7,12-dimethylbenz(a)anthracene (DMBA), shifting the IC50 of DMBA from an estimated 1.2 μM to 400 nM. Diosmin is not cytotoxic in itself at the concentrations tested. Diosmin causes an increase in CYPIAI activity in MCF-7 cells in a time- and dose-dependent fashion. Diosmin causes a dose-dependent increase in CYPIAI mRNA after 24 h of incubation, causes a long-lasting increase in CYPIAI mRNA accumulation that reaches its peak after 48 h of incubation[1].
Diosmin significantly decreases the malondialdehyde (MDA) levels and increases the activities of total-superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in the retina of rats compare with the ischemia group (P<0.05), and suppresses the ischemia/reperfusion (I/R)-induced reduction in the a- and b-wave amplitudes of the electroretinograms (ERGs) (P<0.05). The thickness of the entire retina, inner nuclear layer, inner plexiform layer, and outer retinal layer and the number of cells in the ganglion cell layer are significantly less after I/R injury (P<0.05), and Diosmin remarkably ameliorates these changes on retinal morphology. Diosmin also attenuates the I/R-induced loss of retinal ganglion cells (RGCs) of the rat retina (P<0.05)[2].
References:
[1]. Ciolino HP, et al. Diosmin and diosmetin are agonists of the aryl hydrocarbon receptor that differentially affectcytochrome P450 1A1 activity. Cancer Res. 1998 Jul 1;58(13):2754-60.
[2]. Tong N, et al. Diosmin protects rat retina from ischemia/reperfusion injury. J Ocul Pharmacol Ther. 2012 Oct;28(5):459-66.