College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
Biol Trace Elem Res. 2017 Nov;180(1):153-163. doi: 10.1007/s12011-017-0969-3. Epub 2017 Mar 10.
In this study, we investigated the effects of Agaricus blazei Murill polysaccharides (ABP) on cadmium (Cd)-induced apoptosis and the TLR4 signaling pathway of chicken peripheral blood lymphocytes (PBLs). Seven-day-old healthy chickens were randomly divided into four groups, and each group contained 20 males. The cadmium-supplemented diet group (Cd group) was fed daily with full feed that contained 140 mg cadmium chloride (CdCl)/kg and 0.2 mL saline. The A. blazei Murill polysaccharide diet group (ABP group) was fed daily with full feed with 0.2 mL ABP solution (30 mg/mL) by oral gavage. The cadmium-supplemented plus A. blazei Murill polysaccharide diet group (Cd + ABP group) was fed daily with full feed containing 140 mg CdCl/kg and 0.2 mL ABP solution (30 mg/mL) by gavage. The control group was fed daily with full feed with 0.2 mL saline per day. We measured the apoptosis rate and messenger RNA (mRNA) levels of apoptosis genes (caspase-3, Bax, and Bcl-2), the mRNA levels of TLR4 and TLR4 signaling pathway-related factors (MyD88, TRIF, NF-κB, and IRF3), the TLR4 protein expression, and the concentrations of inflammatory cytokines (IL-1β, IL-6, and TNF-α) in chicken PBLs. The results showed that the PBL apoptosis rate was significantly increased, the mRNA levels of caspase-3 and Bax were significantly increased, while that of Bcl-2 was significantly reduced. The Bax/Bcl-2 ratio was significantly increased in the Cd group at 20, 40, and 60 days after treatment compared with that in the control group. After treatment with ABP, the above changes were clearly suppressed. At the same time, ABP reduced the concentrations of IL-1β, IL-6, and TNF-α induced by Cd. We also found that ABP inhibited the TLR4 mRNA level and protein expression and inhibited the mRNA levels of MyD88, TRIF, NF-κB, and IRF3. The results demonstrated that Cd could induce apoptosis, activate the TLR4 signaling pathway, and induce the expression of inflammatory cytokines in chicken PBLs, and that the administration of ABP clearly inhibited Cd-induced effects on chicken PBLs.
在这项研究中，我们研究了姬松茸多糖（ABP）对镉（Cd）诱导的鸡外周血淋巴细胞（PBL）凋亡及 TLR4 信号通路的影响。将 7 日龄健康雏鸡随机分为 4 组，每组 20 只雄性。在补充镉的饮食组（Cd 组）中，雏鸡每日喂食全价饲料，其中含有 140mg/kg 的氯化镉（CdCl）和 0.2mL 生理盐水。姬松茸多糖饮食组（ABP 组）每日喂食全价饲料，同时灌胃 0.2mL 浓度为 30mg/mL 的姬松茸多糖溶液。补充镉加姬松茸多糖饮食组（Cd+ABP 组）每日喂食全价饲料，同时灌胃 140mg/kg 的氯化镉和 0.2mL 浓度为 30mg/mL 的姬松茸多糖溶液。对照组每天喂食含有 0.2mL 生理盐水的全价饲料。我们检测了鸡 PBL 的凋亡率和凋亡基因（caspase-3、Bax 和 Bcl-2）、TLR4 及 TLR4 信号通路相关因子（MyD88、TRIF、NF-κB 和 IRF3）的信使 RNA（mRNA）水平、TLR4 蛋白表达和促炎细胞因子（IL-1β、IL-6 和 TNF-α）的浓度。结果表明，PBL 的凋亡率显著增加，caspase-3 和 Bax 的 mRNA 水平显著升高，而 Bcl-2 的 mRNA 水平显著降低。与对照组相比，Cd 组处理后 20、40 和 60 天，Bax/Bcl-2 比值显著升高。用 ABP 处理后，上述变化明显受到抑制。同时，ABP 降低了 Cd 诱导的 IL-1β、IL-6 和 TNF-α浓度。我们还发现，ABP 抑制了 TLR4 的 mRNA 水平和蛋白表达，并抑制了 MyD88、TRIF、NF-κB 和 IRF3 的 mRNA 水平。结果表明，Cd 可诱导鸡 PBL 凋亡，激活 TLR4 信号通路，诱导促炎细胞因子表达，而 ABP 可明显抑制 Cd 对鸡 PBL 的诱导作用。
