MicroRNAome in decidua: a new approach to assess the maintenance of pregnancy.
OBJECTIVE
To comparatively analyze the human microRNAomes between normal pregnant and miscarriage deciduas by an in-depth sequencing of microRNA (miRNA); and to specifically examine miRNA-199b-5p and serum/glucocorticoid regulated kinase 1 (SGK1) in vivo and in vitro for their possible roles in pregnancy maintenance.


METHODS
Samples of deciduas from 6-8-week spontaneous miscarriages and normal pregnant women were irrespectively collected and comparatively analyzed by miRNA sequencing. The miR-199b-5p and SGK1 expressions were validated in vivo and in vitro.


METHODS
University research and clinical institutes.


METHODS
In this experimental study, samples of deciduas were obtained from October 2011 to April 2012 from 29 women with spontaneous miscarriages and 35 normal pregnant women (control group) who underwent pregnancy termination at 6-8 weeks at our university gynecology unit.


METHODS
Endometrial biopsies, cell transfection, and production of an miR-199b-5p transgenic mouse model.


METHODS
In-depth sequencing of the miRNAome on human deciduas was performed for statistically significant differences in miRNA expression. Expression levels of SGK1 were detected by quantitative polymerase chain reaction and immunoblotting (Western blot) in vitro while miR-199b-5p is overexpressed or knockdown in miR-199b-5p transgenic mice.


RESULTS
Expression of the 1,921 known miRNAs was analyzed in the study. In aborted deciduas, 0.57% of the miRNAs were expressed abundantly (>10,000 transcripts per million) and represented 86.38% of all the miRNA reads. Six miRNAs were down-regulated (let-7a-5p, let-7f-5p, let-7g-5p, let-7e-5p, let-7d-5p, and miR-98), whereas miR-199b-5p was significantly up-regulated. Overexpression or knockdown of miR-199b-5p in HEK293T and Ishikawa cells decreased or increased SGK1 expression. Furthermore, overexpression of miR-199b-5p in human endometrial stromal cells or in transgenic mouse decreased SGK1 expression at the mRNA and protein levels, respectively.


CONCLUSIONS
Among the miRNAomes, the abundant expression of the let-7 members was decreased in aborted samples, whereas miR-199b-5p expression was consistently increased. A significant inverse correlation was found between miR-199b-5p and SGK1 in vivo and in vitro.
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China; Department of Gynecology and Obstetrics, Inner Mongolia Medical University Affiliated Hospital, Hohhot, People's Republic of China.
Yu
Y
Wang
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Yang
Y
Lv
Department of Gynecology and Obstetrics, Inner Mongolia Medical University Affiliated Hospital, Hohhot, People's Republic of China.
Liyan
L
Wang
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Chunling
C
Gong
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Jiajia
J
Sun
Department of Gynecology and Obstetrics, Inner Mongolia Medical University Affiliated Hospital, Hohhot, People's Republic of China.
Xiujuan
X
Chen
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Yan
Y
Chen
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Lei
L
Yang
College of Bioinformatics Science and Technology, Harbin Medical University, Harbin, People's Republic of China.
Yan
Y
Zhang
Beijing Genomics Institute, Shenzhen, People's Republic of China.
Xukui
X
Yang
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Chunling
C
Bai
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China.
Zhuying
Z
Wei
The Key Laboratory of the National Education Ministry for Mammalian Reproductive Biology and Biotechnology, Inner Mongolia University, Hohhot, People's Republic of China. Electronic address: gpengli@imu.edu.cn.
Guangpeng
G
Li
D000022:Abortion, Spontaneous / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D016022:Case-Control Studies; D002478:Cells, Cultured; D003656:Decidua / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D057809:HEK293 Cells; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D035683:MicroRNAs / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D011247:Pregnancy; D011255:Pregnancy Maintenance / Q000235:genetics*; D011261:Pregnancy Trimester, First / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome; D000099184:Serum-Glucocorticoid Regulated Kinases
D017874:Immediate-Early Proteins; D035683:MicroRNAs; D017346:Protein Serine-Threonine Kinases; D000099184:Serum-Glucocorticoid Regulated Kinases; C531408:mirn199 microRNA, human
MicroRNA; aborted decidua; normal decidua