Di-n-butyl phthalate diminishes testicular steroidogenesis by blocking the hypothalamic-pituitary-testicular axis: relationship with germ cell apoptosis in Japanese quail.

Although di-n-butyl phthalate (DBP) induces germ cell apoptosis, the underlying mechanism is not yet clear in quail. In this study, prepubertal quails were given a single dose of 500mg kg-1 DBP by gavage and were then killed 3, 6 and 24h after treatment. There was a significant reduction in intratesticular testosterone (ITT) concentrations and testicular steroidogenic enzyme mRNA expression and a significant increase in germ cell apoptosis in DBP-treated compared with control quails at all time points. Maximum apoptosis was detected 6h after treatment and the maximum reduction in testosterone concentrations was at 3h. To investigate whether DBP suppressed testicular steroidogenesis by affecting the hypothalamic-pituitary-testicular axis, we analysed pituitary LH subunit ß (Lhb) mRNA expression and serum LH concentrations. At all time points, pituitary Lhb expression and serum LH concentrations were significantly decreased following DBP treatment. The present observations suggest the possibility that DBP blocked LH secretion from the hypothalamus and/or pituitary, thereby decreasing LH stimulation of Leydig cells and reducing ITT concentrations. DBP-induced decreases in ITT concentrations may cause changes to the physical structure of Sertoli cells, which, in turn, may induce germ cell apoptosis.

Role of anlotinib-induced CCL2 decrease in anti-angiogenesis and response prediction for nonsmall cell lung cancer therapy.

BACKGROUND: Anlotinib has been demonstrated in clinical trials to be effective in prolonging the progression-free survival (PFS) and overall survival (OS) of refractory advanced nonsmall cell lung cancer (NSCLC) patients. However, the underlying molecular mechanisms and predictive biomarkers of anlotinib are still unclear. METHODS: A retrospective analysis of anlotinib administered to 294 NSCLC patients was performed to screen for underlying biomarkers of anlotinib-responsive patients. Transcriptome and functional assays were performed to understand the antitumour molecular mechanisms of anlotinib. Changes in serum CCL2 levels were analysed to examine the correlation of the anlotinib response between responders and nonresponders. RESULTS: Anlotinib therapy was beneficial for prolonging OS in NSCLC patients harbouring positive driver gene mutations, especially patients harbouring the epithelial growth factor receptor (EGFR)T790M mutation. Moreover, anlotinib inhibited angiogenesis in an NCI-H1975-derived xenograft model via inhibiting CCL2. Finally, anlotinib-induced serum CCL2 level decreases were associated with the benefits of PFS and OS in refractory advanced NSCLC patients. CONCLUSIONS: Our study reports a novel anti-angiogenesis mechanism of anlotinib via inhibiting CCL2 in an NCI-H1975-derived xenograft model and suggests that changes in serum CCL2 levels may be used to monitor and predict clinical outcomes in anlotinib-administered refractory advanced NSCLC patients using third-line therapy or beyond.

Single administration of butylparaben induces spermatogenic cell apoptosis in prepubertal rats.

Parabens are p-hydroxybenzoic acid ester compounds widely used as preservatives in foods, cosmetics, toiletries and pharmaceuticals. Some parabens, including butylparaben, exert an estrogenic activity as determined by in vitro estrogen receptor assay and in vivo uterotrophic assay, and adversely affect endocrine secretion and male reproductive function. We conducted a research study to evaluate the acute effects of butylparaben on testicular tissues of prepubertal rats. Three-week-old male rats (n=8) were given a single dose of 1000mg/kg butylparaben. The rats were sacrificed under anesthesia at 3, 6 and 24h after administration, and their testes were collected for histopathological examination. The study revealed progressive detachment and sloughing of spermatogenic cells into the lumen of the seminiferous tubules at 3h, and this effect was enhanced at 6h after administration. Thin seminiferous epithelia and wide tubular lumina were seen at 24h in the butylparaben-treated group, compared to the control. In order to clarify whether sloughed spermatogenic cells underwent apoptosis, TUNEL assay was carried out. We found a significant increase in the number of apoptotic spermatogenic cells in all the treated groups, compared to the controls and a maximal number of apoptotic cells were detected at 6h after administration. In semithin sections, apoptotic cells were easily detected by their prominent basophilia and condensed chromatin, mainly found in spermatocytes. Ultrastructurally, the condensed chromatin and shrunken cytoplasm and nucleus, hallmarks of apoptotic cell death, were observed in butylparaben-treated groups. These observations lead us to postulate that butylparaben, similar to other estrogenic compounds, also induces spermatogenic cell apoptosis.

Induction of spermatogenic cell apoptosis in prepubertal rat testes irrespective of testicular steroidogenesis: a possible estrogenic effect of di(n-butyl) phthalate.

Although di(n-butyl) phthalate (DBP), a suspected endocrine disruptor, induces testicular atrophy in prepubertal male rats, whether it exerts estrogenic activity in vivo remains a matter of debate. In the present study, we explored the estrogenic potency of DBP using 3-week-old male rats, and then examined the relationship between estrogen-induced spermatogenic cell apoptosis and testicular steroidogenesis. Daily exposure to DBP for 7 days caused testicular atrophy due to loss of spermatogenic cells, whereas testicular steroidogenesis was almost the same with the control values. A single exposure of DBP decreased testicular steroidogenesis in addition to decreasing the level of serum LH at 3 h after DBP treatment, with an extremely high incidence of apoptotic spermatogenic cells at 6 h after administration. To elucidate the estrogenic activity of DBP, we carried out an inhibition study using pure antiestrogen ICI 182,780 (ICI) in a model of spermatogenic cell apoptosis induced by DBP or estradial-3-benzoate (EB). Although both the DBP- and EB-treated groups showed a significant increase in spermatogenic cell apoptosis, ICI pretreatment significantly decreased the number of apoptotic spermatogenic cells in these two groups. In contrast, testicular steroidogenesis and serum FSH were significantly reduced in all the treated groups, even in the DBP+ICI and EB+ICI groups. Taken together, these findings led us to conclude that estrogenic compounds such as DBP and EB induce spermatogenic cell apoptosis in prepubertal rats, probably by activating estrogen receptors in testis, and that reduction in testicular steroidogenic function induced by estrogenic compounds is not associated with spermatogenic cell apoptosis.