Effects of bilateral ovariectomy and postoperative hormonal replacement therapy with 17beta-estradiol or raloxifene on serum leptin levels.
OBJECTIVE
To verify the effects of hypoestrogenism and replacement therapy on body mass index (BMI) and leptin in ovariectomized women.


METHODS
We conducted a longitudinal study on 56 women undergoing abdominal bilateral ovariectomy divided into three groups: 19 untreated controls, 18 scheduled to receive 17beta-estradiol, and 19 on raloxifene starting 15 days after surgery. Height, weight, and BMI were recorded on the day of surgery, 5 and 15 days later, and then after 6 months. Leptin and estradiol concentrations were determined by radioimmunoassay on the day of surgery, days 1, 5, and 15, and 6 months after.


RESULTS
Leptin levels rose significantly on the day after surgery [median (range): 18.2 (9.8-25.0), 12.5 (9.1-20.9), and 20.5 (12.9-24.5); P< 0.01 v basal] and returned to values similar to baseline on day 5 in all groups. Six months later, controls showed significantly higher leptin levels in comparison with both treated women and basal values [median (range): 19.7 (10.4-22.8), 11.0 (7.6-16.9), and 13.5 (9.1-14.8) ng/ml; P< 0.01). Estradiol levels decreased in all groups, reaching statistical significance 5 days after surgery ( P< 0.01 v basal). A significant rise was observed 6 months after surgery in women treated with estrogens ( P< 0.01). Six months after surgery, BMI increased in untreated controls in comparison with treated women and baseline, although not significantly.


CONCLUSIONS
The absence of modifications in leptin on days 5 and 15 after ovariectomy suggests that, in humans, estrogens may not exert an important effect on leptin secretion. After 6 months, replacement therapy maintained leptin levels and BMI was unmodified, whereas untreated controls showed a significant increase in leptin and a trend toward higher BMI, suggesting that replacement therapy may prevent changes in fat distribution and in leptin levels.
Tommaselli
Giovanni A
GA
Department of Obstetrics and Gynecology, University of Naples "Federico II," the Department of Endocrinology, Second University of Naples, Italy. gtommaselli@yahoo.it
Di Carlo
Costantino
C
Nasti
Anna
A
Giordano
Elena
E
Pisano
Gustavo
G
Pellicano
Massimiliano
M
Bifulco
Giuseppe
G
Nappi
Carmine
C
D000279:Administration, Cutaneous; D000328:Adult; D015992:Body Mass Index; D004958:Estradiol / Q000008:administration & dosage / Q000494:pharmacology; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood / Q000378:metabolism*; D010052:Ovariectomy; D011184:Postoperative Period; D020849:Raloxifene Hydrochloride / Q000008:administration & dosage / Q000494:pharmacology; D020845:Selective Estrogen Receptor Modulators / Q000008:administration & dosage / Q000494:pharmacology
D020738:Leptin; D020845:Selective Estrogen Receptor Modulators; D020849:Raloxifene Hydrochloride; D004958:Estradiol