Abstract: Objective·To analyze the changes of unsaturated free fatty acid profiles and their correlations with body mass index（BMI） and sex hormones in idiopathic central precocious puberty（ICPP） girls. Methods·Fifty-six ICPP girls who were hospitalized in Children’s Hospital of Shanghai Jiao Tong University from August 2020 to January 2021 and 46 normal undeveloped girls at the same age were selected, respectively included in the ICPP group and the control group. The height and weight of the two groups were collected, and the BMI and body mass index standard deviation score（BMI SDS）were calculated. The concentration of serum unsaturated free fatty acid profiles of all the girls as well as the basic and peak values of serum luteinizing hormone（LH） and follicle stimulating hormone（FSH）, estradiol（E2）, sex hormone-binding globulin（SHBG）, and insulin-like growth factor-1（IGF-1） in ICPP girls were detected. The girls who received gonadotropin releasing-hormone analogues（GnRHa） treatment were followed up for 3 months. Finally,48 ICPP girls were enrolled in the follow-up study. The concentrations of serum unsaturated free fatty acid profiles before and after treatment in 48 ICPP girls who completed the follow-up were compared. Multivariate stepwise regression was used to analyze the correlation between serum unsaturated free fatty acid profiles and various indicators. Results·（1） BMI and BMI SDS of the ICPP group were higher than those of the control group（P<0.05）, but there was no correlation between the levels of various unsaturated free fatty acids and BMI（P>0.05）.（2） Compared with the control group, the levels of arachidonic acid（AA, P=0.001）, n-6 docosapentenoic acid（n-6 DPA, P=0.000）, n-3 docosapentaenoic acid（n-3 DPA, P=0.005）, eicosapentaenoic acid（EPA, P=0.010）, docosapentaenoic acid（DHA, P=0.003） and total n-6 polyunsaturated fatty acids（n-6 PUFA, P=0.049） were significantly reduced.（3）The levels of oleic acid（C18:1 n-9, P=0.036）, gondoic acid（C20:1 n-9, P=0.030）, linoleic acid（LA, P=0.020）, γ-Linolenic acid（GLA, P=0.010）, α-linolenic acid（ALA, P=0.009） and total n-6 PUFA（P=0.041） were positively correlated with the peak values of LH. The levels of EPA（P=0.049） and DHA（P=0.046） were negatively correlated with the basic values of LH. The levels of EPA（P=0.020, P=0.002）, n-3 DPA（P=0.003, P=0.001）, DHA（P=0.007, P=0.028）), and total n-3 PUFA（P=0.012, P=0.011） were negatively correlated with the basic values of FSH and E2. The ratio of total n-6 PUFA/total n-3 PUFA was positively correlated with the basic values of FSH（P=0.002）. The peak vaules of FSH, SHBG, and IGF-1 had no correlation with various unsaturated free fatty acids（all P>0.05）.（4）After 3 months of GnRHa treatment, the levels of C16:1（P=0.001）, C18:1（P=0.001）, C20:1（P=0.001）, LA（P=0.013）, GLA（P= 0.013）, and ALA（P=0.032） in ICPP girls were significantly lower than those before treatment, while the levels of AA（P=0.001）, EPA（P=0.000）, and DHA（P=0.025） were significantly higher than those before treatment. Conclusion·ICPP girls were generally overweight or obese, but there was no correlation between the levels of various unsaturated free fatty acids and BMI. Sexual development and GnRHa treatment could affect the metabolism of unsaturated free fatty acids in ICPP girls, and sex hormones were related to a variety of unsaturated free fatty acids.

Key words: idiopathic central precocious puberty, girl, serum unsaturated free fatty acid profile, correlation