Selenium-Alleviated Hepatocyte Necrosis and DNA Damage in Cyclophosphamide-Treated Geese by Mitigating Oxidative Stress.

Selenium (Se) has been well recognized as an immune-enhancing agent with antioxidant and anti-tumor properties. The commonly used chemotherapy drug, cyclophosphamide (CTX), induces liver injury by increasing the reactive oxygen species (ROS) level. However, little is known about how Se alleviates CTX-induced liver injury in geese. In this study, 90 male Magang geese (3 days old) were randomly allocated into three groups (control, CTX, and Se + CTX group) with three replicates per group and ten geese per replicate. The control and CTX groups were fed a basal diet (Se content was 0.03 mg/kg). The Se + CTX group was fed a basal diet containing 0.44 mg/kg sodium selenite (Se content was 0.2 + 0.03 mg/kg). The control group was injected with 0.5 mL saline, while the CTX and Se + CTX groups were injected with CTX at 40 mg/kg body weight per day on days 21-23. The liver index, liver histology, and ultra-micromorphology detected antioxidant enzyme activity in the liver and serum. In addition, we detected the liver marker enzymes and protein levels in serum, and hepatocyte DNA damage. Se could alleviate liver development dysregulation, hepatocyte structural damage, the disturbances in antioxidant enzyme (GPx, CAT, and SOD) activity, and malondialdehyde (MDA) levels in the serum and liver. Besides, Se could alleviate the dysregulation of liver marker enzyme (ALT and AST) activity and protein (ALB and TP) levels in the serum, and DNA migration induced by CTX. In conclusion, Se may inhibit hepatocyte necrosis and DNA damage by inhibiting CTX-induced oxidative stress.

Polysaccharide of Atractylodes macrocephala Koidz Enhances Cytokine Secretion by Stimulating the TLR4-MyD88-NF-κB Signaling Pathway in the Mouse Spleen.

Polysaccharide of Atractylodes macrocephala Koidz (PAMK) has been reported to have beneficial effects on regulation of immune responses in mammals and poultry. Nonetheless, the immunoregulatory mechanism of action of PAMK remains unclear. The Toll-like receptor 4 (TLR4) signaling cascade has been proved as a classic polysaccharide-regulated pathway. The aim of this study was to explore the effects of PAMK on the TLR4 signaling pathway in the regulation of spleen function in mice. Ninety-six 5-week-old BALB/c female mice were randomly allocated into four groups with three replicates per group and eight mice per replicate in a single-factor completely randomized experimental design. The control group was fed a basic diet (PAMK free); the other three groups were fed 100, 200, or 400 mg/kg PAMK for 28 days. The spleen index, concentrations of cytokines, and mRNA and protein expression levels of genes related to TLR4 signaling were determined in spleen tissue. Compared with the control group, the spleen index significantly increased in all treatment groups. Concentrations of interleukin 2 (IL-2), IL-4, interferon γ (IFN-γ), and tumor necrosis factor α (TNF-α) in the medium-PAMK group also increased significantly. PAMK in the medium-PAMK group significantly increased both mRNA and protein expression of TLR4, myeloid differentiation factor 88 (MyD88), TNFR-associated factor 6 (TRAF6), TRAF3, and nuclear factor kappa B (NF-κB) in the spleen. In conclusion, PAMK may increase immune-response capacity of the spleen in mice via TLR4-MyD88-NF-κB signaling.