Abstract
Purpose:
Recent studies indicate that the complement system plays an important role in the pathogenesis of Age related Macular Degeneration (AMD). In a previous study, we found that the serum levels of CFD decreased significantly with daily lutein supplementation. CFD, a rate-limiting component of the alternative complement pathway, is also known as adipsin and is mainly secreted by adipose cells. The purpose of this in vitro study was to determine if lutein influences CFD secretion by adipose cells.
Methods:
The Simpson-Golabi-Behmel syndrome (SGBS) cell line was used to study the effect of lutein on CFD production. Cells were incubated in a medium containing dexamethasone, 3-Isobutyl-1-methylxanthine (IBMX) and rosiglitazone, which allows differentiation of the SGBS cells into mature adipocytes. The obtained mature adipocytes were subsequently stimulated with a dose of 50μg/ml lutein. The supernatants of the SGBS cell cultures were collected at 0, 24 and 48hr and CFD levels were determined by ELISA.
Results:
After culture of SGBS cells in a special differentiation medium we obtained a confluent monolayer of mature adipocytes containing a variable degree of fat globules. Preliminary experiments showed that the culture supernatant contained readily detectable levels of CFD. Further experiments whereby lutein was added to the culture medium showed that the secretion of CFD was markedly inhibited. At 48 hours culture, the supernatant of the control culture contained 820.4pg/ml of CFD whereas the cultures containing lutein showed a concentration of 379.2pg CFD per ml (p=0.015).
Conclusions:
Lutein modulates the production of CFD in mature adipocytes, which may lead to a novel therapeutic approach to control the inflammatory pathway of the innate immune system in AMD.
Keywords: 557 inflammation •
444 carotenoids/carotenoid binding proteins •
412 age-related macular degeneration