METHODS: Huh7 cells and HepG2 cells were cultured with and without
free fatty acid treatment (
palmitate and
linoleate, alone or in combination, 100-1000 μM). Inflammatory pathways,
lipid accumulation, apoptosis and cell viability were monitored.
RESULTS: Dose- and time-related changes of
IL8 mRNA expression were examined and 9 h treatment with 500 μM
palmitate showed the greatest elevation of
IL8. Co-treatment with 500 μM
palmitate and 400 μM
linoleate significantly suppressed
IL8 production below that with
palmitate alone in both cells (both
mRNA and
protein). A quantitative measurement for
lipid accumulation showed no significant difference between
palmitate-treated cells (1.69 ± 0.21),
linoleate-treated cells (1.61 ± 0.16) and
palmitate and
linoleate-treated cells (1.73 ± 0.22, NS, n = 7). The co-treatment with 400 μM
linoleate inhibited phospho-
c-Jun N-terminal kinase (pJNK) activation and IkBα reduction caused by 500 μM
palmitate treatment. Treatment with 400 μM
linoleate alone led to
IL8 production (5.48 fold change), similar to co-treatment, with no influence on the expression of pJNK/IkBα. The cell viability was similar between treatment with 500 μM
palmitate and with both 500 μM
palmitate and 400 μM
linoleate, showing no significant changes in the expression of cleaved
caspase-3.
CONCLUSIONS: