- Academic Editor
†These authors contributed equally.
Objective: To investigate the effects of Ginkgo biloba extract (GBE) on
autophagy in human macrophages stimulated by cigarette smoke extract (CSE).
Methods: The human monocyte cell line U937 was cultured in
vitro, and phorbol ester (PMA) was added to the cell culture medium to induce
differentiation into human macrophages. CSE was prepared by traditional methods
for experiments. The cells were divided into four groups: the blank group, the
CSE model group, the GBE + CSE group, and the rapamycin + CSE group.
Immunofluorescence was used to identify human macrophages, transmission electron
microscopy was used to observe the ultrastructure of human macrophages in each
group, ELISA was used to measure the amount of IL-6 and IL-10 in the supernatant
from each group of cells, the mRNA levels of p62, ATG5, ATG7, and Rab7 were
measured by real-time qPCR, and the protein expression levels of p62, ATG5, ATG7,
and Rab7 were measured by Western blotting. Results: U937 cells were
successfully differentiated into human macrophages after induction with PMA. The
CSE model group had many more autophagosomes than the blank group. Compared with
the CSE model group, the GBE + CSE group and the rapamycin + CSE group had
significantly more autophagolysosomal. Compared with the other groups, the CSE
model group had a higher level of IL-6 but a lower level of IL-10 in the