Toxicity of DON on GPx1-Overexpressed or Knockdown Porcine Splenic Lymphocytes In Vitro and Protective Effects of Sodium Selenite.

Deoxynivalenol (DON) is a common contaminant of grain worldwide and is often detected in the human diet and animal feed. Selenium is an essential trace element in animals. It has many biological functions. The role of selenium in the body is mainly orchestrated by selenoprotein. Glutathione peroxidase (GPx) also exists widely in the body and has attracted much attention due to its high antioxidant capacity. In order to explore the effect of the GPx1 gene on toxicity of DON, in this study, we overexpressed or knockdown GPx1 in porcine splenic lymphocytes, then added different concentrations of DON (0.1025, 0.205, 0.41, and 0.82 µg/mL) and sodium selenite (2 µmol/L) to the culture system. Using various techniques, we detected antioxidant function, free radical content, cell apoptosis, and methylation-related gene expression to explore the effect of GPx1 expression on DON-induced cell damage. We also explored whether selenium can antagonize the toxicity of DON in these two cell models and revealed the protective effect of sodium selenite on DON-induced cell damage in GPx1-overexpressing or knockdown splenic lymphocytes. Finally, our findings revealed the following: (1) GPx1 can regulate the antioxidant capacity, apoptosis rate, and expression of DNA methylation-related genes in pig splenic lymphocytes. (2) Na2SeO3 (2 µmol/L) can regulate the antioxidant capacity, apoptosis rate, and expression of DNA methylation-related genes in pig splenic lymphocytes, and this effect is more significant in GPx1-overexpressing cells than in GPx1-knockdown cells. (3) DON can cause oxidative damage, apoptosis, and methylation injury in GPx1-overexpressing or knockdown pig splenic lymphocytes in a concentration-dependent manner. (4) Na2SeO3 (2 µmol/L) can antagonize the toxic effect of DON on GPx1-overexpressing or knockdown pig splenic lymphocytes. Our findings may have important implications for food/feed safety, human health, and environmental protection.

Evaluation on the efficacy and immunogenicity of recombinant DNA plasmids expressing S gene from porcine epidemic diarrhea virus and VP7 gene from porcine rotavirus.

Porcine rotavirus (PoRV) and porcine epidemic diarrhea virus (PEDV) usually co-infect pigs in modern large-scale piggery, which both can cause severe diarrhea in newborn piglets and lead to significant economic losses to the pig industry. The VP7 protein is the main coat protein of PoRV, and the S protein is the main structural protein of PEDV, which are capable of inducing neutralizing antibodies in vivo. In this study, a DNA vaccine pPI-2.EGFP.VP7.S co-expressing VP7 protein of PoRV and S protein of PEDV was constructed. Six 8-week-old mice were immunized with the recombinant plasmid pPI-2.EGFP.VP7.S. The high humoral immune responses (virus specific antibody) and cellular immune responses (IFN-γ, IL-4, and spleen lymphocyte proliferation) were evaluated. The immune effect through intramuscular injection increased with plasmid dose when compared with subcutaneous injection. The immune-enhancing effect of IFN-α adjuvant was excellent compared with pig spleen transfer factor and IL-12 adjuvant. These results demonstrated that pPI-2.EGFP.VP7.S possess the immunological functions of the VP7 proteins of PoRV and S proteins of PEDV, indicating that pPI-2.EGFP.VP7.S is a candidate vaccine for porcine rotaviral infection (PoR) and porcine epidemic diarrhea (PED).

Laminaria Japonica Polysaccharides effectively inhibited the growth of nasopharyngeal carcinoma cells in vivo and in vitro study.

AIMS: Laminaria Japonica Polysaccharides (LJP) is a kind of plant polysaccharide isolated from Laminaria Japonica Aresch. LJP has a variety of biological activity, including anti-tumor, improving immune function, anti-radiation and others. This study observed the biological activity of LJP in vitro and in vivo on human nasopharyngeal carcinoma(NPC), and the possible anticancer mechanism was explored. METHODS: Nasopharyngeal poorly differentiated squamous cell carcinoma cell lines CNE2 and HONE1 were used for the study. MTT method was used to detect the proliferation of HONE1 and CNE2 treated with gradient concentrations of LJP. The apoptosis of HONE1 treated with LJP was detected by annexin V-FITC/PI double staining method. HONE1 was used to establish subcutaneous implanted tumor model in nude mice. The changes of transplanted tumor volume and body weight of nude mice in each group were observed and recorded. The changes of the ultrastructure of transplanted tumor were observed by transmission electron microscope (TEM). RESULTS: MTT results showed that LJP has inhibitory effect on proliferation of both HONE1 and CNE2, and the effects were dosage-dependent; results of flow cytometry (FCM) analysis showed that, LJP could efficient induce apoptosis in HONE1, and apoptosis rate increased with the increase of LJP concentration. In vivo experiments, the inhibition rate was 33.7% (P<0.05) and 47% (P<0.01) in middle and high dose LJP group, respectively. TEM results suggested that the cancer cells in the transplanted tumor tissue treated with middle and high dose LJP presented unique apoptosis changes. CONCLUSIONS: LJP can effectively inhibit the growth of NPC cells. And it may be achieved by inducing apoptosis of NPC cells.

[Tumor suppressive effect and relative mechanisms of tea polyphenol on nasopharyngeal carcinoma cells].

OBJECTIVE: To investigate the effect and mechanism of tea polyphenol (TP) on the proliferation, apoptosis, migration and invasion of nasopharyngeal carcinoma(NPC) cell line HONEl. METHOD: After treated with different concentration of tea polyphenol, CCK-8 assay, fluorescent staining, cell scratching assay and transwell assay were applied to detect the effect of tea polyphenol on the HONE1 cells. Furthermore, the expression of protein VEGF was investigated by flow cytometry assay. RESULT: It was found that tea polyphenol could inhibit NPC cell proliferation significantly in a dose-dependent manner, however, little impact was observed in normal nasopharyngeal epithelial cell line NP69. Furthermore, it was demonstrated by fluorescent staining assay that tea polyphenol could induce NPC cell apoptosis, and cell scratching assay and transwell assay showed that tea polyphenol could inhibit cell migration and invasion. CONCLUSION: Tea polyphenol can significantly inhibit cell proliferation, induce cell apoptosis and decreased the migration and invasion ability of NPC cells in vitro. Tea polyphenol might be a tumor suppressor of NPC cells.

[Advances on the anti-tumor and anti-radiation effect of tea polyphenols in nasopharyngeal carcinoma].

NPC is a high incidence of malignant tumors of the head and neck, and is currently used mainly radiotherapy based, supplemented by a comprehensive treatment of chemotherapy, radiotherapy and chemotherapy, which have serious complications and serious impact on the treatment of patients and quality of life. Polyphenols are the main component of tea. Studies have shown that tea polyphenols have a significant anti-tumor effect of im proving the effect of radiotherapy and chemotherapy, reducing radiation damage, reducing conventional chemo therapy drugs IC50 and reducing the complications of chemotherapy. Tea polyphenols in the treatment of nasopharyngeal carcinoma has also made great progress. It has a strong inhibition of nasopharyngeal carcinoma cells, and can greatly reduce the occurrence of xerostomia after radiotherapy, which is of important clinical research value.

[The effects of tea polyphenols and Laminaria japonica polysaccharides on nasopharyngeal carcinoma cell HONE1 and CNE2].

OBJECTIVE: To explore the effects of laminaria japonica polysaccharides(LJP) and tea polyphenols (TP) on nasopharyngeal carcinoma(NPC) cells HONE1 and CNE2, and further to explore the underlying mechanism of antitumor activity of LJP on NPC cell in vivo. METHOD: To identify the logarithmic growth phase of NPC cells HONE1 and CNE2 through cell growth curve and doubling time by means of MTT, then inhibition of the cells proliferation were detected with LJP and TP separately and combined. With LJP treatment, cell apoptosis of HONE1 was examined by double staining assay. A tumor model,established by subcutaneously inoculation of NPC cell HONE1 into nude mice,was used to evaluate the inhibitory effect of LJP in vivo. RESULT: Both LJP and TP had inhibition effect on two groups of cell proliferation, and LJP and TP combined effect of inhibition were higher than the two separate on two sets of experimental cell proliferation, whose effect was concentration-dependent. LJP could induce apoptosis of HONE1. With the increasing concentration of LJP, apoptosis rate increased. The apoptosis rate was(49.51 +/- 1. 89) % (P<0. 01) when treated with 320 mg/L LJP. The inhibition rate was between 50% to 60% at 72 h after treatment with 320 mg/L LJP. Compared to control group, the growth of xenografts in nude mice was significantly suppressed after administration of LJP at a dose-dependent manner. The inhibition rates were 33. 7%(P<0. 05)and 47. 0%(P<0. 01) when treated with 25.0 mg/kg and 50. O mg/kg respectively. Whereas the inhibition rate of 12.5 mg/kg group was only 16. 4%(P>0. 05). CONCLUSION: LJP and TP can inhibit the proliferation of NPC cells HONE1 and CNE2 respectively,and combined use has a significant effect. LJP can inhibit the growth of NPC probably by inducing apoptosis of NPC cells in vitro and in vivo.

Tea polyphenols protect against irradiation-induced injury in submandibular glands' cells: a preliminary study.

AIM: To study the protective effect of tea polyphenols (TPs) on submandibular glands affected by radiation injury. METHODS: Sixty rats were randomly divided into radiation group (R-group, N = 30) and TP-pre-treated-radiation group (TPR-group, N = 30). The rats were intragastrically administered with TP or normal sodium from 14 days before radiation, continuously daily, until the experiment. All the rats in both groups were irradiated with a single exposure dose of 15 Gy gamma rays that were delivered to the head and neck areas. Ten rats of each group were anatomised on the 3rd, 6th and 30th day after irradiation, respectively. The submandibular glands of the rats were removed for the study. The morphologic changes of the submandibular glands were observed by transmission electron microscopy (TEM). The terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-biotin nick-end labelling (TUNEL) method was used to detect apoptosis of the submandibular glands' cells. RESULTS: Electron microscope observation of the submandibular glands showed that the lesions of the TPR-group were mild. Change in apoptosis of the cells was not obvious compared with the R-group. The cell apotosis was typical after irradiation in the R-group. Apoptosis index that was detected in the cells of submandibular glands of the TPR-group was statistically significantly decreased compared with the R-group (P < 0.01) on the 3rd, 6th and 30th day after irradiation. CONCLUSION: TP could protect submandibular glands from radiation injuries, and the protection mechanism may be realised by anti-apoptosis.

Anxiolytic-Like Effect of baicalin and its additivity with other anxiolytics.

Baicalin, a naturally occurring flavonoid, was previously reported to exert anxiolytic-like effects in the Vogel conflict test. In the present study, the anxiolytic effects of baicalin alone and in combination with other anxiolytics were tested in mice using the elevated plus-maze (EPM). Baicalin treatment (7.5 - 30 mg/kg) significantly increased entries into and time spent in open arms, indicative of an anxiolytic-like effect. Motor-depressive and myorelaxant side effects commonly associated with anxiolytics were not observed with baicalin at effective anxiolytic doses in the hole-board and horizontal wire tests, respectively. Co-administration of baicalin (3.75 mg/kg) with dl-tetrahydropalmatine ( dl-THP; 0.25 mg/kg), an anxiolytic-hypnotic alkaloid, both at sub-effective doses, induced an additive effect resulting in considerable anxiolysis. Similarly, an additive anxiolytic-like effect was observed with baicalin (3.75 mg/kg) and diazepam (DZ; 0.5 mg/kg). Results obtained from this study demonstrate the potential of baicalin as a candidate anxiolytic and its possible application in multidrug therapy. Abbreviations. BZS:benzodiazepine-binding site EPM:elevated plus-maze DZ:diazepam GABA (A):type A gamma-aminobutyric acid dl-THP: dl-tetrahydropalmatine.