Pathogenetic regularity of female precocious puberty and the mechanism of therapy with traditional Chinese medicine
Cai depei*, Ji Zhiying*, Chen Baiying**, Zhang Wei***
( *Pediatric Hospital Shanghai Medical University, Shanghai 200032, **Department of Neurobiology Shanghai Medical University, ***Shanghai PASIC Bio-engineering Institute )

　　In recent ten-odd years the pathogenetic regularity of female idiopathic precocious puberty was researched in our hospital, in terms of the function of hypothalamic-pituitary-gonadal axis and the status of skeletal development as indicators. The regime of the therapy with a predominance of Chinese herbal medicine (CHM) was formulated, according to recognition for the regularity of differential diagnosis with method of traditional Chinese medicine (TCM). It has been clinically verified that the regime could successfully modulate the course of pubertal development and optimize skeletal development in children with precocious puberty. The mechanism of effectiveness of the drugs has been further researched focusing of the neuroendocrine regulation and gene expression with modern medical technique.

　　Pathogenetic regularity of idiopathic true precocious puberty:
　　The function of hypothalamic-pituitary-gonadal axis was determined in girls with idiopathic true precocious puberty at various stages of pubertal development, with GnRH stimulating test, serum E2 content and exfoliative cytoscopy of the vagina, and the analysis of correlativity between various parameters and the extent of precocious puberty. The results showed that the hypothalamic-pituitary-ovarian axis in the girls with precocious puberty started earlier than normal and was in a state of hyperfunction, there were characteristic changes in their reactive curve and peak value, and the more serious the condition of the illness, the more obvious the hyperfunctional state was(1). The parameters of skeletal development were determined, including serum Osteocalcin, X-ray bone age and bone mineral density with single photon absorptiometry. The results showed that function of the osteoblasts in the girls was overactive, skeletal growth was accelerated and skeletal maturity was advanced, and the longer the course of the disease, the more obvious the extent of acceleration and more advanced the state were. Since epiphyses fusion occurred earlier, the final height would be shorter(2).

　　The regularity of differential diagnosis using TCM method and the therapeutic regime of CHM:
　　The differential diagnosis to idiopathic true precocious puberty was made with diagnostic method of TCM. It was observed that each girl had the feature of "Yin Xu Huo Wang" to a certain extent, and was very remarkable in most of them. The feature consist of intolerance of hot, thirst, flush face, restlessness, feverish sensation of the palms, soles and chest, perspiring during sleep, constipation, crimson tongue. According to recognition for the regularity of differential diagnosis using method of TCM, it has been claimed that the pathogenesis of female precocious puberty is of unbalance between "Shen Yin" and "Shen Yang" in the girls, deficiency of "Shen Yin" and exuberance of "Xiang Huo" ( intense internal heat arisen due to deficiency of vital essence ), resulting in growth acceleration, premature emergence of sexual characteristics and menstruation, it belongs to a manifestation of regulative disturbance of "Shen" to growth, development and reproductive function(3). In view of the above mentioned, a therapeutic regime has been formulated, including the CHM of "Zi ShenYin Xie Xiang Huo" (nourishing vital essence to remove the intense internal heat) adopted at the onset of the disease to induce remission, to consolidate and maintain curative effect after the remission, then the CHM of "Yi Shen Tian Jing" ( invigorating vital function and replenish vital essence ) was adopted instead at the time of reaching normal adolescent age to facilitate better pubertal development.
　　The effect and mechanism of CHM on treating precocious puberty in clinical aspect:
　　1. The regulative effect of CHM on hypothalamic-pituitary-gonadal function in children with precocious puberty:
　　The hypothalamic-pituitary-gonadal function were monitored, the uterus and ovary volumes were measured with ultrasound during the therapeutic course. The results showed that through the treatment of CHM "Zi Shen Yin Xie Xiang Huo", the level of serum FSH, LH, E2 descended, the peak value of LH in the GnRH stimulating test lowered and the reactive curve returned to normal, the volume of uterus and ovary reduced, and secondary sexual characteristics retrogressed(4). At the time of reaching normal adolescent age, the CHM of "Yi Shen Tian Jing" was adopted instead, that could invigorate again the hypothalamic-pituitary-ovarian function, the level of serum FSH, LH, E2 rose, the volume of uterus and ovary enlarged, secondary sexual characteristics reappeared and the onset of menarche occurred. The results demonstrated that both these CHM possesses obviously regulating the hypothalamic-pituitary-gonadal function in girls with precocious puberty, thereby could play a role in modulating the course of pubertal development.
　　2. The effect of CHM on ameliorating skeletal development in children with precocious puberty:
　　The above mentioned parameters of skeletal development were monitored in the therapeutic course. The results showed that the CHM of "Zi Shen Yin Xie Xiang Huo" could inhibit excessive functional activities of the osteoblasts, the level of serum Osteocalcin descend, skeletal linear growth decelerated and skeletal maturity delayed, thereby could prevent epiphyseal from prematurely fusing and increase the final height(5). The CHM of "Yi Shen Tian Jing" could reactivate the function of osteoblasts, resulting in elevation of the level of serum Osteocalcin. The results demonstrated that both these CHM could ameliorate skeletal development of the girls, thereby could increase their final height.

　　The effect and mechanism of CHM on experimental treatment of precocious puberty:
　　1. The effect and mechanism of CHM on modulating hypothalamic-pituitary-gonadal function:
　　The pubertal rats have been fed with CHM of "Zi Shen Yin Xie Xiang Huo" or "Yi Shen Tian Jing". The content of GnRH, the frequency and amplitude of GnRH pulse releasing, and the releasing amount of aminoacid neurotransmitters and β-endorphin in the gonadotropic area of the hypothalamus were determined with neurobiological experimental methods, included the push-pull perfusion of medial preoptic area in the hypothalamus, the incubation of the brain slices of medial basal hypothalamus, and the immunohistochemical method. The levels of the gene expression of GnRH in the hypothalamus, FSH & LH in the adenohypophysis were determined with quantitative RT -PCR(6). The results showed that the CHM of "Zi Shen Yin Xie Xiang Huo" could reduce the activity of GnRH neurons in the hypothalamus through inhibiting the release of central exciting aminoacid neurotransmitters and promoting the releasing of central inhibiting aminoacid neurotransmitter and  β-endorphin, the level of the mRNA expression of GnRH down regulated, the biosynthesis and secretion of GnRH decreased, thereby could inhibit hypothalamic-pituitary gonadotropic function. The CHM of "Yi Shen Tian Jing" could up regulate the mRNA expression of GnRH in the hypothalamus, FSH & LH in the adenohypophysis, thereby promote hypothalamic-pituitary gonadotropic function. The results demonstrated that both these CHM could modulate the hypothalamic-pituitary-gonadal function through acting upon the neuroendocrine regulative mechanism, it could be one of chief effective mechanism of these CHM on successfully modulating the course of pubertal development in children with precocious puberty.
　　2. The effect and mechanism of CHM on ameliorating skeletal development:
　　GHRH mRNA and  SS mRNA expression in hypothalamus were measured with in situ
　　Hybridization .GH mRNA expression in hypophysis , IGF-1 mRNA expression in Liver , IGF-1 mRNA and Osteocalcin mRNA expression in metaphysis were measured in  experimental animals.It was observed that the CHM of “Zi Shen Yin Xie Xiang Huo”could up regulate the gene expression and protein level of SS in the periventricular nucleus of hypothalamus , down regulate the gene expression and protein level of GH in hypophysis , down regulate the gene expression of IGF-1 in liver ,and down regulate the gene expression of IGF-1 and Osteocalcin in metaphysis,thereby could inhibit hypothalamic-pituitary somatotrophic function and functional activities of the osteoblasts,whereas the CHM of “Yi Shen Tian Jing” could down regulate the gene expression and protein level of SS in the periventricular nucleus of hypothalamus, up regulate the gene expression and protein level of GH in hypophysis, up regulate the gene expression of IGF-1 in liver ,and up regulate the gene expression of IGF-1 and Osteocalcin in metaphysis, thereby could promote hypothalamic-pituitary somatotrophic function and functional activities of the osteoblasts. The results demonstrated that both these CHM could regulate the gene expression of SS in hypothalamus , GH in hypophysis , IGF-1 in metaphysis and Osteocalcin in osteoblast, which could be one of chief mechanism of  these CHM on ameliorating skeletal development in children with precocious puberty.

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