Title |
A small hairpin RNA targeting myeloid cell leukemia-1 enhances apoptosis in host macrophages infected with Mycobacterium tuberculosis |
Author |
Fei-yu Wang1,2, Yu-qing Zhang1,2, Xin-min Wang2,3, Chan Wang2,4, Xiao-fang Wang1,2, Jiang-dong Wu1,2, Fang Wu1,2, Wan-jiang Zhang1,2, and Le Zhang1,2* |
Address |
1Department of Pathophysiology, Medical College of Shihezi University, Xinjiang, P. R. China, 2Key Laboratory of Xinjiang Endemic and Ethnic Diseases Cooperated by Education Ministry with Xinjiang Province, Xinjiang, Shihezi, P. R. China, 3Department of Urinary Surgery, the First Affiliated Hospital, Xinjiang, Shihezi, P. R. China, 4Department of Pathogen Biology and Immunology, Medical College of Shihezi University, Xinjiang, P. R. China |
Bibliography |
Journal of Microbiology, 54(4),330-337, 2016,
|
DOI |
10.1007/s12275-016-5627-5
|
Key Words |
apoptosis, Mcl-1, Mcl-1-shRNA, Mycobacterium tuberculosis, host macrophages |
Abstract |
Myeloid cell leukemia-1 (Mcl-1) plays an important role in
various cell survival pathways. Some studies indicated that
the expression of Mcl-1 was upregulated in host cells during
infection with the virulent Mycobacterium tuberculosis strain,
H37Rv. The present study was designed to investigate the
effect of inhibiting Mcl-1 expression both in vivo and in vitro
on apoptosis of host macrophages infected with M. tuberculosis
using a small hairpin (sh)RNA. Mcl-1 expression was detected
by the real time-polymerase chain reaction, western blotting,
and immunohistochemistry. Flow cytometry and transmission
electron microscopy were used to measure host macrophage
apoptosis. We found elevated Mcl-1 levels in host macrophages
infected with M. tuberculosis H37Rv. The expression of Mcl-1
was downregulated efficiently in H37Rv-infected host macrophages
using shRNA. Knockdown of Mcl-1 enhanced the
extent of apoptosis in H37Rv-infected host macrophages
significantly. The increased apoptosis correlated with a decrease
in M. tuberculosis colony forming units recovered from
H37Rv-infected cells that were treated with Mcl-1-shRNA.
Reducing Mcl-1 accumulation by shRNA also reduced accumulation
of the anti-apoptotic gene, Bcl-2, and increased
expression of the pro-apoptotic gene, Bax, in H37Rv-infected
host macrophages. Our results showed that specific knockdown
of Mcl-1 expression increased apoptosis of host macrophages
significantly and decreased the intracellular survival
of a virulent strain of M. tuberculosis. These data indicate that interference with Mcl-1 expression may provide
a new avenue for tuberculosis therapy. |