The effects of soy extract on the uterus of castrated adult rats.
OBJECTIVE
The aim of this study was to evaluate the effects of different doses of a standardized soy extract on the uterus of castrated rats.


METHODS
Fifty-six adult castrated female Wistar rats were randomly divided into seven groups (eight animals in each) that received: GI--drug vehicle (propylene glycol); GII--soy extract 10mg/kg per day; GIII--soy extract 50mg/kg per day; GIV--soy extract 100mg/kg per day; GV--soy extract 300mg/kg per day; GVI--soy extract 600mg/kg per day; GVII-conjugated equine estrogens (CEE) 200microg/kg per day. After 21 days of treatment, all animals were sacrificed and fragments of the uterine horns were immediately removed, fixed in 10% formaldehyde and submitted to routine histological techniques for morphometric study. The endometrial cell proliferation index was determined with the PCNA antibody PC-10 and expressed as the percentuals of the PCNA-positive nuclei relative to the total countings. Other fragments were immediately frozen in liquid nitrogen for RNA extraction and VEGF analysis using RT-PCR technique.


RESULTS
The minimal dose of soy extract that produced a significant increase of the morphometric parameters was 100mg/kg (GIV). The maximum effects on endometrial and myometrial morphometry were detected in the groups treated with 300 and 600mg/kg of soy extract (groups V and VI) and CEE (GVII). The expression of PCNA in the endometrial epithelium and stroma was increased by treatment with 100-600mg/kg per day of soy extract (groups IV-VI) or with CCE (group VII). Doses equal to or higher than 50mg/kg of soy extract (groups III-VI) and CEE stimulated the expression of VEGF.


CONCLUSIONS
The treatment of adult castrated rats during 21 days with doses of 100mg/kg per day or higher of soy extract may determine significant proliferation in the endometrium and myometrium.
Mosquette
Rejane
R
Department of Gynecology, Federal University of São Paulo, Rua Sena Madureira 1245, 04021051 São Paulo, Brazil.
de Jesus Simões
Manuel
M
da Silva
Ismael Dale Cotrim Guerreiro
ID
Oshima
Celina Tizuko Fujiyama
CT
Oliveira-Filho
Ricardo Martins
RM
Haidar
Mauro Abi
MA
Simões
Ricardo Santos
RS
Baracat
Edmund Chada
EC
Soares Júnior
José Maria
JM
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004958:Estradiol / Q000097:blood; D005260:Female; D009929:Organ Size / Q000187:drug effects; D010052:Ovariectomy; D010936:Plant Extracts / Q000494:pharmacology*; D011374:Progesterone / Q000097:blood; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013025:Glycine max / Q000737:chemistry*; D014599:Uterus / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
D010936:Plant Extracts; D018809:Proliferating Cell Nuclear Antigen; D042461:Vascular Endothelial Growth Factor A; C467498:vascular endothelial growth factor A, rat; D011374:Progesterone; D004958:Estradiol