RESUMEN
Electroacupuncture (EA) is effective in various chronic pains. NF-κB and CXCL12 modulate the formation of chronic pain. Herein, we hypothesized that EA alleviates cancer-induced bone pain (CIBP) through NF-κB/CXCL12 axis in midbrain periaqueductal gray (PAG), which participates in "top-down" pain modulatory circuits. In order to filter the optimum EA frequency for CIBP treatment, 2, 100, or 2/100 Hz EA was set up. In addition, ipsilateral, contralateral, and bilateral EA groups were established to affirm the optimal EA scheme. Bilateral 2/100 Hz EA was considered as the optimal therapeutic scheme and was applied in a subsequent experiment. Western blotting along with immunofluorescence illustrated that CIBP induces a rapid and substantial increase in CXCL12 protein level and NF-κB phosphorylation in vlPAG from day 6 to day 12. Anti-CXCL12 neutralizing antibody and pAAV-U6-shRNA(CXCL12)-CMV-EGFP-WPRE in vlPAG remarkably improved the mechanical pain threshold of the hind paw in CIBP model relative to the control. EA inhibited the upregulation of pNF-κB and CXCL12 in vlPAG of CIBP. The recombinant CXCL12 and pAAV-CMV-CXCL12-EF1a-EGFP-3Xflag-WPRE reversed the abirritation of EA in the CIBP rat model. NF-κB phosphorylation mediated-CXCL12 expression contributed to CIBP allodynia, whereas EA suppressed NF-κB phosphorylation in CIBP. According to the above evidence, we conclude that bilateral 2/100 Hz EA is an optimal therapeutic scheme for CIBP. The abirritation mechanism of EA might reduce the expression of CXCL12 by inhibiting the activation of NF-κB, which might lead to the restraint of descending facilitation of CIBP.
Asunto(s)
Electroacupuntura , Neoplasias , Animales , FN-kappa B/metabolismo , Umbral del Dolor , Sustancia Gris Periacueductal/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Ziram is an endocrine disruptor and may cause birth abnormality of the male reproductive system. However, the effects of ziram on fetal Leydig cell (FLC) development are still unknown. The objective of the present study was to determine the endocrine-disrupting effect of ziram on rat FLC development after gestational exposure. Pregnant Sprague Dawley dams were randomly divided into 5 groups and were gavaged with 0 (corn oil, the control), 1, 2, 4, or 8â¯mg/kg ziram from gestational day 12 (GD12) to GD21. FLC development was evaluated by measuring serum testosterone, FLC number and distribution, and the expression levels of Leydig and Sertoli cell genes. Ziram significantly increased serum testosterone level at 1â¯mg/kg (1.350⯱â¯0.099â¯ng/ml vs. 0.989⯱â¯0.106â¯ng/ml in the control), while it remarkably lowered it at 8â¯mg/kg (0.598⯱â¯0.086â¯ng/ml). Quantitative immunohistochemical staining showed that ziram increased FLC number via stimulating cell proliferation at 1â¯mg/kg and lowered it via inhibiting its proliferation at 8â¯mg/kg without affecting Sertoli cell number. Further study demonstrated that the expression of Nr5a1, Lhcgr, Scarb1, Star, Cyp11a1, and Cyp17a1 genes and proteins in the testis was upregulated at 1â¯mg/kg and the expression of Leydig (Nr5a1, Lhcgr, Scarb1, Star, Cyp11a1, Cyp17a1, and Insl3) and Sertoli cell (Fshr, Hsd17b3, Dhh, Amh, and Sox9) genes and proteins was downregulated by ziram at 8â¯mg/kg. In conclusion, ziram had biphasic effects on FLC development with low dose to increase FLC number and function and high dose to decrease them.