[The influence of hormonal replacement therapy on the certain collagen metabolites].
OBJECTIVE
Collagen is the most abundant protein within the human body. It constitutes about 80% of the organic part of all tissues. Type I collagen constitutes 95% of the organic part of the bone. Therefore the measuring of the carboxyterminal telopeptide of type I collagen (ICTP), cross-linked via pyridinoline and liberated during the degradation of type I collagen, enables monitoring of the bone collagen degradation. Biosynthesis of collagen includes several posttranslational modifications, among them the propeptides cleavage from the N and C terminal parts of the molecule. Measuring of these products is a useful indicator of the collagen biosynthesis rate.


OBJECTIVE
To evaluate the influence of hormonal replacement therapy on degradation of type I collagen as measured by ICTP and biosynthesis of type III collagen as measured by PIIINP (N terminal propeptide of type III collagen).


METHODS
The above mentioned markers of collagen metabolism were measured in sera of 25 women (mean age 49.12 +/- 3.01 years) who underwent abdominal hysterectomy with bilateral salpinpo-ophorectomy because of benign diseases. The control group included 25 women matched for age and body mass who did not receive any treatment. Immediately after surgery HRT constituted of Estraderm TTS50 and Provera 10 mg sequentially was established in every patients. Blood for biochemical investigations was collected before surgery and after 6 and 12 months of the therapy. Serum ICTP and PIIINP concentrations were measured by RIA method using commercially available kits from Orion Diagnostica-Finland.


RESULTS
It was found that HRT significantly decreased serum ICTP concentrations and this was accompanied by the increase in the biosynthesis of type III collagen as measured by PIIINP. Moreover, a strong negative correlation was found between bone mineral density and ICTP in both investigated groups.


CONCLUSIONS
1) HRT significantly decreased type I collagen breakdown as measured by ICTP concentrations. 2) Type III collagen biosynthesis as measured by PIIINP concentration steadily increased during HRT. 3) The diagnostic use of ICTP measurement altogether with the bone mineral density could be a useful predictor for the risk of the bone fracture during menopause.
Czarnacki
J
J
Oddziału Ginekologiczno-Połozniczego Szpitala Rejonowego w Parczewie.
Jabłoński
M
M
Walawski
J
J
Rechberger
T
T
D000328:Adult; D003094:Collagen / Q000096:biosynthesis* / Q000097:blood*; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D020249:Hormone Replacement Therapy / Q000379:methods*; D006801:Humans; D008525:Medroxyprogesterone / Q000494:pharmacology*; D008875:Middle Aged
D004958:Estradiol; D003094:Collagen; D008525:Medroxyprogesterone