Aim: 

To elucidate if changes produced by the enrichment of culture medium of pancreatic AR42J cells with different fatty acids depend on the length of the exposure period.

Methods: 

AR42J cells were cultured for 3 or 6 days in medium enriched with either oleic (3O/6O) or linoleic (3L/6L) acid, according to the method described previously (Audi et al., 2007). Membrane fatty acid profile was determined by gas–liquid chromatography. Amylase activity in 50-min incubation supernatants was measured photometrically and results expressed as a percentage of the initial content of the cells.

Results: 

In all cases, a longer exposure period enhanced membrane unsaturation index. Higher MUFA, total PUFA and n-3 PUFA, and lower SFA content were found in 6O cells compared to 3O cells. This was accompanied by significant differences in net amylase release stimulated by 1 nM cholecystokinin-octapeptide. Culture of AR42J cells with linoleic acid-enriched medium for six days (6L) instead of three (3L) resulted in increased membrane content of total and n-6 PUFA and decreased content of SFA and MUFA. This effect was paralleled by a reduction in unstimulated amylase secretion.

Conclusion: 

Our results confirm that, similarly to the observations in in vivo studies on adaptation to dietary fat, changes in membrane fatty acid profile and in the functional response of AR42J cells induced by enrichment of culture medium with different fatty acids depend on the length of the adaptation period.

Audi et al. (2007) Exp Biol Med 232, 532–541.

Supported by MEC (BFI2002-02772, AGL-2006-05005).