Skeletal muscle plays a paramount role in physical activity, metabolism, and energy balance, while its homeostasis is being challenged by multiple unfavorable factors such as injury, aging, or obesity. Exosomes, a subset of extracellular vesicles, are now recognized as essential mediators of intercellular communication, holding great clinical potential in the treatment of skeletal muscle diseases. Herein, we outline the recent research progress in exosomal isolation, characterization, and mechanism of action, and emphatically discuss current advances in exosomes derived from multiple organs and tissues, and engineered exosomes regarding the regulation of physiological and pathological development of skeletal muscle. These remarkable advances expand our understanding of myogenesis and muscle diseases. Meanwhile, the engineered exosome, as an endogenous nanocarrier combined with advanced design methodologies of biomolecules, will help to open up innovative therapeutic perspectives for the treatment of muscle diseases.
Exosomes/physiology* ; Muscle, Skeletal/metabolism* ; Cell Communication ; Homeostasis

BACKGROUND: Tumor growth and invasion are interconnected with the tumor microenvironment. Overexpression of genes that regulate cancer cell invasion by growth factors, cytokines, and lipid factors can affect cancer aggressiveness. A comparative gene expression analysis between highly invasive and low invasive cells revealed that various genes are differentially expressed in association with invasive potential. In this study, we selected variant PC-3 prostate cancer cell sublines and discovered critical molecules that contributed to their invasive potential. METHODS: The high invasive and low invasive variant PC-3 cell sublines were obtained by serial selection following Matrigel-coated Transwell invasion and were characterized by Transwell invasion, luciferase reporter assay, and Rhotekin pull-down assay. Lysophosphatidic acid (LPA) was added to the cultures to observe the response to this extracellular stimulus. The essential molecules related with cancer invasiveness were detected with Northern blotting, quantitative reverse transcription-polymerase chain reaction, and cDNA microarray. RESULTS: Highly invasive PC-3 cells showed higher nuclear factor kappa B (NF-kappaB), activator protein 1 (AP-1) and RhoA activities than of low invasive PC-3 cells. LPA promoted cancer invasion through NF-kappaB, AP-1, and RhoA activities. Thrombospondin-1, interleukin-8, kallikrein 6, matrix metalloproteinase-1, and tissue factor were overexpressed in the highly invasive PC-3 variant cells and further upregulated by LPA stimulation. CONCLUSIONS: The results suggest that the target molecules are involved in invasiveness of prostate cancer. These molecules may have clinical value for anti-invasion therapy by serving as biomarkers for the prediction of aggressive cancers and the detection of pharmacological inhibitors.
Biomarkers ; Blotting, Northern ; Cytokines ; Gene Expression ; Intercellular Signaling Peptides and Proteins ; Interleukin-8 ; Kallikreins ; Luciferases ; Matrix Metalloproteinase 1 ; NF-kappa B ; Oligonucleotide Array Sequence Analysis ; Prostate* ; Prostatic Neoplasms* ; Thromboplastin ; Transcription Factor AP-1 ; Tumor Microenvironment

GPR43 (G protein-coupled receptor 43) is a recently discovered short-chain free fatty acid receptor which plays important role in adipogenesis. Here we explored the transcriptional expression rule of GPR43 in porcine adipose tissue and primary cultured adipocytes. Partial cDNA of GPR43 was successfully cloned from swine by RT-PCR and the expression profile of GPR43 mRNA was studied from different types, different growing stages, and different sites of porcine adipose tissue as well as porcine primary cultured adipocytes. The results showed that porcine GPR43 shared high homology with human (89%), mouse (84%) and rat (83%). The expression level of GPR43 mRNA was significantly higher in adipose tissue of obese pigs than that of lean pigs, and also the expression level gradually increased with age. Further, the abundance of GPR43 mRNA level was higher in subcutaneous fat than in visceral fat. In addition, during the adipocytes differentiation, the expression of GPR43 mRNA increased in a time-dependent manner. These data indicated that GPR43 gene expression was relate to the site of adipose tissue, economic type, and age of pig as well as differentiating state of adipocytes, implying that GPR43 can be a potential factor to regulate adipogenesis.
Adipocytes ; cytology ; metabolism ; Adipose Tissue ; metabolism ; Animals ; Cells, Cultured ; DNA, Complementary ; biosynthesis ; genetics ; Gene Expression Profiling ; Humans ; RNA, Messenger ; biosynthesis ; genetics ; Receptors, Cell Surface ; biosynthesis ; genetics ; Receptors, G-Protein-Coupled ; biosynthesis ; genetics ; Swine ; Transcription, Genetic

In order to examine the role of astacene on mice body development and the expression of energy metabolism related genes in mice, we treated mice (Kunming white) and primary culture of mouse muscle cells with astacene of higher and lower concentration. Then the total mRNA was extracted from the muscle tissue and cells respectively, and the mRNA levels of UCP3 and LXRalpha were detected by RT-PCR in all the samples. Compared with the control group, the body weight of mice in high concentrations of astacene group grown slowly, and the expressions of UCP3 genes decreased significantly in muscle tissue of the 10th day and the 30th day as well as the cells of treated for 24 h (P<0.05). The expression of LXRalpha gene increased significantly in all samples (P<0.05) and reached its peak at 72 h (P<0.01). With the treatment of lower concentration of astacene, the expressions of UCP3 and LXRalpha gene mRNA in muscle tissue did not alter much, but in muscle cells treated for 24 h, the mRNA level of UCP3 gene decreased significantly (P<0.05), and LXRalpha gene increased significantly (P<0.05). The results suggest that astacene has a role in regulating the energy use in mice muscle.
Animals ; Carotenoids ; pharmacology ; Cells, Cultured ; Dose-Response Relationship, Drug ; Energy Metabolism ; drug effects ; genetics ; Ion Channels ; genetics ; metabolism ; Liver X Receptors ; Male ; Mice ; Mitochondrial Proteins ; genetics ; metabolism ; Muscle, Skeletal ; cytology ; metabolism ; Orphan Nuclear Receptors ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Uncoupling Protein 3

Inhalation injury is caused by inhalation of heat, toxic or irritating gases which lead to respiratory and pulmonary parenchyma damage. At present, the clinical understanding about it is still limited and lack of effective diagnosis and treatment standard. Based on the experience of diagnosis and treatment of domestic inhalation injury, combined with reports of international researches, criteria (expert consensus) for inhalation injury were systematically discussed from pathological and pathophysiological changes, clinical diagnosis and evaluation, and clinical treatment, which provides reference for clinical diagnosis and treatment of patients inflicted with inhalation injury.
Burns, Inhalation ; Consensus ; Humans ; Lung ; Smoke Inhalation Injury ; diagnosis ; therapy

We aimed to obtain the recombinant aminopeptidase encoded by Listeria monocytogenes (L. monocytogenes) gene lmo1711, and characterized the enzyme. First, the amino acid sequences of Lmo1711 from L. monocytogenes EGD-e and its homologues in other microbial species were aligned and the putative active sites were analyzed. The putative model of Lmo1711 was constructed through the SWISS-MODEL Workspace. Then, the plasmid pET30a-Lmo1711 was constructed and transformed into E. coli for expression of the recombinant Lmo1711. The his-tagged soluble protein was purified using the nickel-chelated affinity column chromatography. With the amino acid-p-nitroaniline as the substrate, Lmo1711 hydrolyzed the substrate to free p-nitroaniline monomers, whose absorbance measured at 405 nm reflected the aminopeptidase activity. The specificity of Lmo1711 to substrates was then examined by changing various substrates, and the effect of metal ions on the catalytic efficiency of this enzyme was further determined. Based on the bioinformatics data, Lmo1711 is a member of the M29 family aminopeptidases, containing a highly conserved catalytic motif (Glu-Glu-His-Tyr-His-Asp) with typical structure arrangements of the peptidase family. The recombinant Lmo1711 with a size of about 49.3 kDa exhibited aminopeptidase activity and had a selectivity to the substrates, with the highest degree of affinity for leucine-p-nitroaniline. Interestingly, the enzymatic activity of Lmo1711 can be activated by Cd²⁺, Zn²⁺, and is strongly stimulated by Co²⁺. We here, for the first time demonstrate that L. monocytogenes lmo1711 encodes a cobalt-activated aminopeptidase of M29 family.

OBJECTIVEIn order to investigate the possible mechanism of its function to degrade lipid, we detect the effects of hawthorn flavanone to the influence on blood-fat levels and adipogenesis genes transcription expression in fat and muscle tissue of hyperlipoidemia mouse.

METHODIn this experiment, a total of 48 mouse were randomised to four groups and irrigated with two different concentrations (1.5 g kg(-1) body weight and 3.0 g kg(-1) body weight) of hawthorn flavanone, and killed in 0 h, 1 h, 2 h and 4 h. To estimate the content of TC, TG and HCL-C in blood: Total RNA was isolated from adipose and muscle, Real-time RT-PCR was used to analyze expression changes of adipogenesis genes (SREBP-1c, FAS, HSL and TGH) with time series; to analyze the correlation between TG in blood and some kinds of adipogenesis genes and the ratio of FAS/HARMEAN (HSL, TGH) mRNA in adipose.

RESULTHawthorn flavanone was able to cut down the level ofTC, TG and HDL significantly in blood and achieved the lowest level at 1 h. In adipose tissue, hawthorn flavanone up-regulated FAS, HSL and TGH, and achieved the level of significance (P<0.05), the expression level of FAS and TGH was ascend after 1 h, but HSL descend. The expression level of SREBP-1c was descend rapidly and achieved the level of significance after treating with hawthorn flavanone at 1 h (P<0.05), after that it rise again to even higher than the level of before treatment. After treating with hawthorn flavanone, the ratio of FAS/HARMEAN (HSL, TGH) in adipose was significantly descend and achieved the lowest level at 1 h (P<0.01), but it was descendsubsequently. In muscle tissue, hawthorn flavanone was able to significantly up-regulated the expression of FAS and HSL and lower dose group showed greater increasing, the change of SREBP-1c was similar in adipose tissue except the more heavily upgrade.

CONCLUSIONHawthorn flavanone had the function of depressing the concentration of blood-fat, it co-adjusted lipid metabolism of animal by regulating the transcription expression of FAS, HSL, TGH and SREBP-1c especially HSL and SREBP-1c transcription level.

Adipose Tissue ; drug effects ; metabolism ; Animals ; Crataegus ; chemistry ; Flavanones ; pharmacology ; Gene Expression Regulation ; drug effects ; Hyperlipidemias ; blood ; genetics ; Lipids ; blood ; Lipogenesis ; drug effects ; Lipolysis ; drug effects ; genetics ; Male ; Mice ; RNA, Messenger ; genetics ; metabolism ; Sterol Regulatory Element Binding Protein 1 ; genetics ; Triglycerides ; blood ; Up-Regulation ; drug effects ; fas Receptor ; genetics

We describe a genetic transformation method of secondary somatic embryogenesis in alfalfa through cotyledon-stage somatic embryos of alfalfa infected by Agrobacterium strain GV3101. The Agrobacterium strain GV3101 contained binary vector pCAMBIA2301 that had gus gene as reporter and npt II gene as selectable marker. The infected primary embryos were induced through series of medium under 75 mg/L kanamycin selection. We obtained the transgenic alfalfa plants. Then, GUS expression in different tissue of transgenic alfalfa was tested by GUS histochemical analysis. Further, the stable integration and transformation efficiency were tested by polymerase chain reaction and Southern blotting hybridization. The result showed that GUS expression was different in different organs of transgenic alfalfa; the copy number of integrated npt II gene was from 1 to 4; the transformation efficiency via primary somatic embryogenesis was 65.82%.
Agrobacterium ; genetics ; Medicago sativa ; embryology ; genetics ; physiology ; Plant Somatic Embryogenesis Techniques ; Plants, Genetically Modified ; embryology ; genetics ; Tissue Culture Techniques ; Transformation, Genetic

MicroRNA (miRNA) is a type of highly conserved nucleotide sequence composed of 18 to 25 nucleotides, which can specifically bind to the 3'-noncoding regions of mRNA, and then play a negative regulatory role in degrading mRNA or inhibiting translation. Long non-coding RNA (lncRNA) is a type of nucleotide sequence that exceeds 200 nucleotides in length and cannot encode proteins or can only encode protein peptides. It regulates gene expression at the levels of epigenetic, transcriptional and post-transcriptional. As an important energy storage organ, fat plays an important role in regulating the energy balance of animals, and is closely related to meat production traits such as meat production and meat quality. And the disorder of fat function can lead to hyperlipidemia, type 2 diabetes and a series of cardiovascular diseases, so the molecular regulation mechanism of animal fat deposition has attracted more attention. In recent years, more and more studies have found that miRNA and lncRNA play a crucial role in animal fat deposition. We review here the current research progresses in the role of miRNA and lncRNA in animal fat deposition, to provide theoretical guidance and new ideas for further revealing the molecular regulation mechanism of animal fat deposition.

Clustered regulatory interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease (Cas9), the third-generation genome editing tool, has been favored because of its high efficiency and clear system composition. In this technology, the introduced double-strand breaks (DSBs) are mainly repaired by non-homologous end joining (NHEJ) or homology-directed repair (HDR) pathways. The high-fidelity HDR pathway is used for genome modification, which can introduce artificially controllable insertions, deletions, or substitutions carried by the donor templates. Although high-level knock-out can be easily achieved by NHEJ, accurate HDR-mediated knock-in remains a technical challenge. In most circumstances, although both alleles are broken by endonucleases, only one can be repaired by HDR, and the other one is usually recombined by NHEJ. For gene function studies or disease model establishment, biallelic editing to generate homozygous cell lines and homozygotes is needed to ensure consistent phenotypes. Thus, there is an urgent need for an efficient biallelic editing system. Here, we developed three pairs of integrated selection systems, where each of the two selection cassettes contained one drug-screening gene and one fluorescent marker. Flanked by homologous arms containing the mutated sequences, the selection cassettes were integrated into the target site, mediated by CRISPR/Cas9-induced HDR. Positively targeted cell clones were massively enriched by fluorescent microscopy after screening for drug resistance. We tested this novel method on the amyloid precursor protein (APP) and presenilin 1 (PSEN1) loci and demonstrated up to 82.0% biallelic editing efficiency after optimization. Our results indicate that this strategy can provide a new efficient approach for biallelic editing and lay a foundation for establishment of an easier and more efficient disease model.
Alleles ; CRISPR-Cas Systems ; DNA End-Joining Repair ; Gene Editing/methods* ; Recombinational DNA Repair