Lutein loaded double-layered polymer nanocarrier modulate H2O2 and CoCl2 induced oxidative and hypoxia damage and angiogenic markers in ARPE-19 cells.

Lutein plays a crucial role in the protection of retina by diminishing oxidative stress in diabetic retinopathy (DR).
However, its poor aqueous solubility, chemical instability and low bioavailability edge its application. Also,
beneficial effects of lutein supplementation and lower lutein levels in the serum and retina of DR patients created
an interest in nanopreparation. Hence, lutein-loaded chitosan‑sodium alginate nanocarrier comprising oleic acid
core (LNCs) was developed and examined its protective effect on hyperglycemia-mediated changes in oxidative
stress and angiogenesis in ARPE-19 cells. Results showed that the LNCs have smaller size and a smooth spherical
morphology and did not affect the ARPE-19 cell viability (up to 20 μM) and showed higher cellular uptake in
both normal and H2O2-induced stress conditions. LNCs pre-treatment suppressed the H2O2-induced oxidative
stress and CoCl2-induced hypoxia-mediated elevation of intracellular reactive oxygen species, protein carbonyl
and malondialdehyde levels by restoring antioxidant enzymes in ARPE-19 cells. Further, LNCs protected H2O2-
mediated down-regulation of Nrf2 and its downstream antioxidant enzymes. LNCs also restored the H2O2-altered
angiogenic (Vascular endothelial growth factor (VEGF), X-box binding protein 1 (XBP-1) and Hypoxia-inducible
factor 1-alpha (HIF-1α)), endoplasmic reticulum stress (activating transcription factor-4 (ATF4)) and tight
junction (Zona occludens 1 (ZO-1)) markers. To conclude, we could successfully develop biodegradable LNCs to
improve the cellular uptake of lutein to treat DR by curtailing oxidative stress in retina.