2.5. Cell culture, viability assay and intervention
The mouse NIT-1 pancreatic β cells were provided by Department
of Immunology, Tongji Medical College, Huazhong University of
Science and Technology. The cells were cultured in RPMI-1640
medium supplemented with 10% FBS, 100 units/ml penicillin and
100 units/ml streptomycin and maintained at 37 1C in a humidified
atmosphere of 5% CO2 and 95% air. Mediums containing different
types of rat serum (10% low dose JLDG serum, 10% intermediate dose
JLDG serum, 10% high dose JLDG serum, 10% PIO serum) were prepared
to identify cytotoxicity by MTT assay.
NIT-1 cells were seeded at 5 103 cells per well in 96 well-culture
plates. After cells have adhered, the medium was replaced by serum
containing different dugs. The cell viability in the serum containing
different concentration of drugs was evaluated by MTT assay according
to manufacturer’s protocol. Under the conditions of this study, 10%
intermediate dose JLDG serum and 10% PIO serum had negligible
effect on cell viability (data not shown).
Approximately, 1 105
/ml cells were transferred into two 6-well
plates and allowed to grow overnight to 70% confluence. Then all
types of culture mediums were respectively replaced according to the
different cell groups as follows. The culture medium in control group
contained 10% FBS. The medium in model group contained PA
(0.25 mmol/l) and 0.5% BSA. The mediums in different treatment
groups as below also contained PA(0.25 mmol/l), respectively. Furthermore,
the medium in JLDG group contained 10% intermediate
dose JLDG serum. The medium in AICAR group contained AICAR
(0.5 mmol/l) and 0.5% BSA. The medium in Compound C group
contained 10% intermediate dose JLDG and Compound C (10 μmol/l).
The medium in PIO group contained 10% PIO serum. For the detection