[Expression characteristics of transforming growth factor-beta1 in human skin at different development stages of gestation].
OBJECTIVE
To investigate gene expression of transforming growth factor-beta(1) (TGF-beta(1)) and its two upstream signalling factors (smad2 and smad3) in fetal skin at different gestational ages and postnatal skin and its potential biological significance.


METHODS
Fetal skin samples of human embryo were obtained from spontaneous abortions at different gestational ages ranging from 13 to 32 weeks, and also skin collected from patients undergoing plastic surgery. After morphological characteristics of skin at different developmental stages were examined histologically, gene expressions of TGF-beta(1), smad2 and smad3 in skin specimens at different developmental stages were examined with reverse transcription-polymerase chain reaction analysis (RT-PCR).


RESULTS
Gene expression of TGF-beta(1), smad2 and smad3 could all be detected in fetal skin and skin after birth. In skin from early gestational fetus, gene expressions of TGF-beta(1) and smad2 were weak. Along with advance in gestational age, gene expression of these two genes in skin became progressively stronger. In skin from late gestational fetus and skin after birth, the transcription contents of these two genes were significantly increased compared with early gestation fetus (P<0.05). On the contrary, gene expression of smad3 was apparently higher in younger fetal skin versus elder compared with that of late fetal skin (P<0.05). In skins after birth, the levels of smad3 gene expression were elevated to the level similar to that in early gestational fetal skin.


CONCLUSIONS
The signal pathway mediated by TGF-beta(1) might be involved in regulating development of the skin at embryonic stage and in designating cetaceous structure and function, and also in wound healing after birth. The relative lack in expression of TGF-beta(1) and smad2 genes in skins from younger fetuses might contribute to fetal scar-less healing, in which the role of smad3 needs to be further investigated.
Chen
Wei
W
Key Research Laboratory of Wound Repair, Burns Institute, 304 th Hospital of PLA, Beijing 100037, China.
Fu
Xiao-bing
XB
Ge
Shi-li
SL
Sun
Tong-zhu
TZ
Jiang
Du-yin
DY
Zhou
Gang
G
Sheng
Zhi-yong
ZY
D000199:Actins / Q000235:genetics; D000367:Age Factors; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000196:embryology / Q000378:metabolism*; D051899:Smad2 Protein; D015534:Trans-Activators / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000235:genetics*; D053773:Transforming Growth Factor beta1
D000199:Actins; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; C497782:SMAD2 protein, human; D051899:Smad2 Protein; C508960:TGFB1 protein, human; D015534:Trans-Activators; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1