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Chicken coccidiosis, caused by Eimeria protozoa, affects poultry farming. Toll‐like receptors (TLRs) and host defence peptides (HDPs) help host innate immune responses to eliminate invading pathogens, but their roles in Eimeria tenella infection remain poorly understood. Herein, 14‐day‐old chickens were treated orally with 50,000 E. tenella oocysts and the cecum was dissected at different timepoints. mRNA expression of 10 chicken TLRs (chTLRs) and five HDPs was measured by quantitative real‐time PCR. chTLR7 and chTLR15 were upregulated significantly at 3 h post‐infection while other chTLRs were downregulated (p <.05). chTLR1a, chTLR1b, chTLR2b and chTLR4 peaked at 36 h post‐infection, chTLR3, chTLR5 and chTLR15 peaked at 72 h post‐infection and chTLR21 expression was highest among chTLRs, peaking at 48 h post‐infection (p < 0.05). For HDPs, cathelicidin (CATH) 1 to 3 and B1 peaked at 48 h post‐infection, liver‐expressed antimicrobial peptide 2 peaked at 96 h post‐infection, and CATH 2 expression was highest among HDPs. CATH2 and CATH3 were markedly upregulated at 3 h post‐infection (p <.05). The results provide insight into innate immune molecules during E. tenella infection in chicken, and indicate that innate immune responses may mediate resistance to chicken coccidiosis. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) are both historically important therapeutic agents and important source of new drugs. Halofuginone (HF), a small molecule alkaloid derived from febrifugine, has been shown to exert strong antiproliferative effects that differ markedly among various cell lines. However, whether HF inhibits MCF‐7 cell growth in vitro and underlying mechanisms of this process are not yet clear. Here, we offer the strong evidence of the connection between HF treatment, exosome production and proliferation of MCF‐7 cells. Our results showed that HF inhibits MCF‐7 cell growth in both time‐ and dose‐dependent manner. Further microRNA (miRNA) profiles analysis in HF treated and nontreated MCF‐7 cell and exosomes observed that six miRNAs are particularly abundant and sorted in exosomes. miRNAs knockdown experiment in exosomes and the MCF‐7 growth inhibition assay showed that exosomal microRNA‐31 (miR‐31) modulates MCF‐7 cells growth by specially targeting the histone deacetylase 2 (HDAC2), which increases the levels of cyclin‐dependent kinases 2 (CDK2) and cyclin D1 and suppresses the expression of p21. In conclusion, these data indicate that inhibition of exosome production reduces exosomal miR‐31, which targets the HDAC2 and further regulates the level of cell cycle regulatory proteins, contributing to the anticancer functions of HF. Our data suggest a new role for HF and the exosome production in tumorigenesis and may provide novel insights into prevention and treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Skeletal muscle is the most abundant tissue in the body. The development of skeletal muscle cell is complex and affected by many factors. A sea of microRNAs (miRNAs) have been identified as critical regulators of myogenesis. MiR‐208b, a muscle‐specific miRNA, was reported to have a connection with fiber type determination. However, whether miR‐208b has effect on proliferation of muscle cell was under ascertained. In our study, cyclin‐dependent kinase inhibitor 1A (CDKN1A), which participates in cell cycle regulation, was predicted and then validated as one target gene of miR‐208b. We found that overexpression of miR‐208b increased the expression of cyclin D1, cyclin E1, and cyclin‐dependent kinase 2 at the levels of messenger RNA and protein in cattle primary myoblasts in vivo and in vitro. Flow cytometry showed that forced expression of miR‐208b increased the percentage of cells at the S phase and decreased the percentage of cells at the G0/G1 phase. These results indicated that miR‐208b participates in the cell cycle regulation of cattle primary myoblast cells. 5‐Ethynyl‐20‐deoxyuridine and 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assays showed that overexpression of miR‐208b promoted the proliferation of cattle primary myoblasts. Therefore, we conclude that miR‐208b participates in the cell cycle and proliferation regulation of cattle primary skeletal muscle cell through the posttranscriptional downregulation of CDKN1A. Our data demonstrated that cyclin‐dependent kinase inhibitor 1A (CDKN1A) is a target gene of microRNA (miR)‐208b. MiR‐208b participates in the cell cycle and proliferation regulation of cattle primary skeletal muscle cell through the posttranscriptional downregulation of CDKN1A. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs or miRs) are small noncoding RNAs that play critical roles in muscle cell proliferation and differentiation via post‐transcriptional regulation of gene expression. Here, based on our previous high‐throughput sequencing results, we evaluated miRNA‐499 (miR‐499) functions during myoblast proliferation and differentiation. In addition, we analyzed miR‐499 expression profiles and characterized the associated functional roles. MiR‐499 is known to be a skeletal muscle fiber‐type‐associated miRNA. However, its roles in skeletal myoblast proliferation and differentiation are poorly understood. MiR‐499 overexpression promoted C2C12 cell proliferation and significantly attenuated C2C12 cell myogenic differentiation. Furthermore, miR‐499 inhibition enhanced C2C12 cell proliferation and suppressed C2C12 cell differentiation. Using dual‐luciferase reporter assays and western blot analysis, we confirmed that miR‐499 targeted transforming growth factor β receptor 1 (TGFβR1), a known regulator of skeletal myoblast development. Additionally, our RNA interference analysis, in which TGFβR1 was downregulated, showed that TGFβR1 significantly promoted the differentiation of C2C12 cells and inhibited their proliferation. The effects of overexpression and interference of miR‐499 on the proliferation and differentiation of myoblasts at different time points were explored using a variety of experimental techniques, and related regulatory mechanisms were explored. The results revealed that miR‐499 targets myofibroblast proliferation and differentiation by targeting transforming growth factor β receptor 1. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) have been identified in various tissues and cell types from human, monkey, porcine, and mouse. However, knowledge on circRNAs in bovine muscle development is limited. We downloaded and analyzed the circRNAs sequencing data of bovine skeletal muscle tissue, and further characterized the role of a candidate circRNA (circFUT10) in muscle development. Quantitative real‐time PCR (qPCR) and Western blot assays were used to confirm the expression of genes involved in myoblasts differentiation and proliferation. Flow cytometry was performed to assess cell cycle distribution and cell apoptosis. EdU incorporation and CCK‐8 assay were performed to demonstrate cell proliferation. We demonstrated that circFUT10 was highly (but differentially) expressed in embryonic and adult skeletal muscle tissue. circFUT10 induced bovine primary myoblasts differentiation and increased the expression of MyoD, MyoG, and MyhC in mRNA and protein levels. circFUT10 increased the number of myoblasts in the G0/G1 phase of the cell cycle, and decreased the proportion of cells in the S‐phase. circFUT10 inhibited the proliferation of myoblasts and promoted them apoptosis. Via a luciferase screening assay, circFUT10 is observed to sponge to miR‐133a with three potential binding sites. Specifically, we show that circFUT10 regulated myoblasts differentiation and cell survival by directly binding to miR‐133a and inhibiting miR‐133a activity. Modulation of circFUT10 expression in muscle tissue may emerge as a potential target in breeding strategies attempting to control muscle development in cattle. [ABSTRACT FROM AUTHOR]