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Enterotoxigenic Escherichia coli (ETEC) remains a massive burden in developing countries with increasing morbidity and mortality rates; it is also an important pathogen in the farming industry and is a leading cause of bacterial diarrhea. Our previous study showed that nanometer-sized inclusion bodies (IBs) of the fimbrial adhesin subunit protein (FaeG), mutation heat-stable enterotoxin a (mSTa), heat-labile enterotoxin b (LTb), and STb (nontargeting) fusion protein as an oral vaccine induced both systemic and mucosal immune responses. In this study, to enhance the protective efficacy to ETEC, we used Yersinia enterocolitica adhesive and M-cell-targeting peptides to analyze high-efficiency antigen-specific immune presentation in the gut. Here, we showed that immunization with the IBs of ETEC-FaeG-mSTa-LTb-STb-induced a specific systemic and mucosal immune response in the gut, whereas the combination of both targeting peptides resulted in the highest titer, protective immune response against ETEC. A lymphocyte proliferation assay has shown that the IBs induced immunologic memory. The specific antibody of the targeting groups could effectively neutralize toxins, thereby protecting the cells of the small intestine and reducing the level of cAMP and cGMP, and the groups with double targeting showed the best effect. The most important finding was that the targeting peptides stimulate the T helper (Th) cells through Th17 and Th1 and that Th1 cells dominated the cellular immune response. We found that the targeting peptide could also activate CD11c+ on lymphoid dendritic cells, which processed and presented antigens to T cells through Th1-mediated IFN-γ and IL-12, thereby enhancing the antibody titers. The double-targeting peptide had a better effect on stimulating the immune cells to enhance the antibody titers.-Jiang, X., Xia, S., He, X., Ma, H., Feng, Y., Liu, Z., Wang, W., Tian, M., Chen, H., Peng, F., Wang, L., Zhao, P., Ge, J., Liu, D. Targeting peptide-enhanced antibody and CD11c+ dendritic cells to inclusion bodies expressing protective antigen against ETEC in mice.

Oocyte competence is an important determinant of reproductive success and can be disrupted by heat/cold stress. Information related to seasonally induced cold stress effects in cold areas on oocyte competence in the bovine is still scarce, however. Therefore, we performed experiments to test the hypothesis that seasonally induced cold/heat stress affects bovine oocyte competence in cold areas. Oocytes were collected in the winter, summer, and autumn, and we showed a significantly better survival and growth rate in the cold compared with hot temperatures, as recorded for two-cell and blastocyst stage embryos (P

MicroRNAs (miRNAs) regulate gene expression by inhibiting the translation of target RNA. Clenbuterol (CLB) is a β-adrenergic agonist that has the ability to modify muscle characteristics by promoting protein synthesis and inhibiting the growth of fat. To determine the expression profile of miRNAs in the muscle of CLB-treated Chinese miniature swine and to predict their target genes, 13 microRNAs were detected and analyzed. We found that miR-133, miR-206, and miR-1 exhibited the highest expression, although no difference in expression levels was observed between the control and the treatment groups, whereas miR-29a and miR-29b were differentially expressed in the CLB-treated muscles. Furthermore, we analyzed the relationship between miR-29a/b expression, muscle growth, and candidate target genes, and determined that the expression of the four target genes (HnRNPF, SWI/SNF, TPM1, and LPL) was regulated by miR-29a and miR-29b and were functionally related to muscle development.

Aims: Lactobacillus strains have protective effects against heavy metals while relieving oxidative stress and modulating the immune response. Mechanisms that ameliorate heavy metal toxicity and the relationship between probiotics and gut barrier protection in the process of heavy metal pathogenesis was poorly understood. Methods and Results: In this study, Lactobacillus brevis 23017 (LAB, L. brevis 23017), a selected probiotics strain with strong mercury binding capacities, was applied to evaluate the efficiency against mercury toxicity in a mouse model. Histopathological results along with HE stains show that L. brevis 23017 protects the integrity of the small intestinal villus, which slows weight loss in response to Hg exposure. The qRT-PCR results demonstrate that L. brevis 23017 maintains a normal mucosal barrier via modulation of tight junction proteins. Importantly, the present study demonstrates that L. brevis 23017 effectively ameliorates injury of the small intestine by reducing intestinal inflammation and alleviating oxidative stress in animal models. Moreover, L. brevis 23017 blocks oxidative stress and inflammation through MAPK and NF-κB pathways, as shown by western blot. Conclusions: Together, these results reveal that L. brevis 23017 may have applications in the prevention and treatment of oral Hg exposure with fermented functional foods by protecting gut health in daily life.

Streptococcus suis (S. suis) form biofilms and causes severe diseases in humans and pigs. Biofilms are communities of microbes embedded in a matrix of extracellular polymeric substances. Eradicating biofilms with the use of antibiotics or biocides is often ineffective and needs replacement with other potential agents. Compared to conventional agents, promising and potential alternatives are biofilm-inhibiting compounds without impairing growth. Here, we screened a S. suis adhesion inhibitor, rutin, derived from Syringa. Rutin, a kind of flavonoids, shows efficient biofilm inhibition of S. suis without impairing its growth. Capsular polysaccharides(CPS) are reported to be involved in its adherence to influence bacterial biofilm formation. We investigated the effect of rutin on S. suis CPS content and structure. The results showed that rutin was beneficial to improve the CPS content of S. suis without changing its structure. We further provided evidence that rutin specifically affected S. suis biofilm susceptibility by affecting CPS biosynthesis in vitro. The study explores the antibiofilm potential of rutin against S. suis which can be used as an adhesion inhibitor for the prevention of S. suis biofilm-related infections. Nevertheless, rutin could be used as a novel natural inhibitor of biolfilm and its molecular mechanism provide basis for its pharmacological and clinical applications.

The Min pig (Sus scrofa) is a well-known indigenous breed in China. One of its main advantages over European breeds is its high meat quality. Additionally, different cuts of pig also show some different traits of meat quality. To explore the underlying mechanism responsible for the differences of meat quality between different breeds or cuts, the longissimus dorsi muscle (LM) and the biceps femoris muscle (BF) from Min and Large White pigs were investigated using transcriptome analysis. The gene expression profiling identified 1371 differentially expressed genes (DEGs) between LM muscles from Min and Large White pigs, and 114 DEGs between LM and BF muscles from the same Min pigs. Gene Ontology (GO) enrichment of biological functions and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the gene products were mainly involved in the IRS1/Akt/FoxO1 signaling pathway, adenosine 5′-monophosphate-activated protein kinase (AMPK) cascade effects, lipid metabolism and amino acid metabolism pathway. Such pathways contributed to fatty acid metabolism, intramuscular fat deposition, and skeletal muscle growth in Min pig. These results give an insight into the mechanisms underlying the formation of skeletal muscle and provide candidate genes for improving meat quality. It will contribute to improving meat quality of pigs through molecular breeding.

Deregulation of Roundabout homolog 1 (Robo1) has been demonstrated to be associated with several types of human cancer, including gastric cancer. However, the detailed role of Robo1 and its regulatory mechanism in gastric cancer remain largely unclear. In the current study, it was demonstrated that the expression of microRNA (miR)‑29a was frequently reduced in gastric cancer tissues, compared with their matched normal adjacent tissues. Similar results were additionally observed in AGS and SGC‑7901 human gastric cancer cells. Overexpression of miR‑29a led to reduced migration and invasion of AGS cells. To explore the targets of miR‑29a in gastric cancer, bioinformatics analysis was conducted and Robo1 was identified as a putative target of miR‑29a. Further western blotting and luciferase activity assay data confirmed that miR‑29a was able to negatively regulate the protein expression of Robo1, through directly binding to the 3'‑untranslated region of Robo1 mRNA in gastric cancer cells. In addition, it was demonstrated that Robo1 was frequently upregulated in gastric cancer tissues compared with their matched adjacent normal tissues, and a significant inverse correlation was identified between miR‑29a and Robo1 expression. In addition, knockdown of Robo1 by small interfering RNA markedly inhibited the migratory and invasive capabilities of AGS cells, which the results obtained with overexpression of miR‑29a. In conclusion, to the best of our knowledge the current study suggested for the first time, that miR‑29a inhibits migration and invasion in part via direct inhibition of Robo1 in gastric cancer cells. Therefore, Robo1 and miR‑29a may serve as diagnostic or therapeutic targets for gastric cancer.