Effects of Dietary Selenium Against Lead Toxicity Are Related to the Ion Profile in Chicken Muscle.

Complex antagonistic interactions between Selenium (Se) and heavy metals have been reported in previous studies. However, little is known regarding the effects of Se on lead (Pb)-induced toxicity and the ion profile in the muscles of chickens. In this present study, we fed chickens either Se or Pb or both Se and Pb supplement and later analyzed the concentrations of 26 ions in chicken muscle tissues. We determined that a Se- and Pb-containing diets significantly affected microelements in chicken muscle. Treatment with Se increased the content of Se but resulted in a reduced concentration of Cu, As, Cd, Sn, Hg, and Ba. Treatment with Pb increased concentrations of Ni while reducing those of B, V, Cr, Fe, Co, Cu, Zn, and Mo. Moreover, Se also reduced the concentration of Pb, Zn, Co, Fe, V, and Cr, which in contrast were induced by Pb. Additionally, we also found that synergistic and antagonistic interactions existed between Se and Pb supplementation. Our findings suggested that Se can exert a negative effect on Pb in chicken muscle tissues and may be related to changes in ion profiles.

Lack of telomerase activity in rabbit bone marrow stromal cells during differentiation along neural pathway.

OBJECTIVE: To investigate telomerase activity in rabbit bone marrow stromal cells (BMSCs) during their committed differentiation in vitro along neural pathway and the effect of glial cell line-derived neurotrophic factor (GDNF) on the expression of telomerase. METHODS: BMSCs were acquired from rabbit marrow and divided into control group, GDNF (10 ng/ml) group. Cytokine.NSCs medium (prepared by our lab, Patent No. ZL02134314. 4) supplemented with 10 percent fetal bovine serum (FBS) was used to induce BMSCs differentiation along neural pathway. Fluorescent immunocytochemistry was employed to identify the expressions of Nestin, neuron-specific endase (NSE), and gial fibrillary acidic protein (GFAP). The growth curves of the cells and the status of cell cycles were analyzed, respectively. During the differentiation, telomerase activities were detected using the telomeric repeat amplification protocol-enzyme-linked immunosorbent assay (TRAP-ELISA). RESULTS: BMSCs were successfully induced to differentiate along neural pathway and expressed specific markers of fetal neural epithelium, mature neuron and glial cells. Telomerase activities were undetectable in BMSCs during differentiation along neural pathway. Similar changes of cell growth curves, cell cycle status and telomerase expression were observed in the two groups. CONCLUSIONS: Rabbit BMSCs do not display telomerase activity during differentiation along neural pathway. GDNF shows little impact on proliferation and telomerase activity of BMSCs.