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 Acute lymphoblastic leukemia (ALL) and chemotherapy can cause immune imbalance,and gaseous molecule hydrogen sulfide (H2S) can participate in the process of immune response.This study aimed to investigate the immune regulation of H2S in pediatric ALL.Methods Children (n=78) with ALL admitted during 2010-2013 were included in this study.Two blood samples were collected in period of before chemotherapy,bone marrow remission and two days after chemotherapy,respectively.Serum contents of H2S and cytokines,including interleukin-1β (IL-13),interleukin-2 (IL-2),interferon-γ (IFN-γ),tumor necrosis factor (TNF-α),interleukin-4 (IL-4),interleukin-6 (IL-6),interleukin-10 (IL-10) and macrophage inflammatory protein-1α (MIP-1a),were detected using ELISA method.Stepwise regression was used to analyze the correlation between H2S and cytokines.Furthermore,human Jurkat cells were cultured in vitro,and nucleoprotein of Jurkat cells and peripheral blood mononuclear cells (PBMCs) were collected,contents of cystathionine γ-lyase (CSE) and certain cytokines were measured by Western blotting.Results Serum concentrations of H2S,IL-13,IL-6,IL-10 and MIP-1α in children with ALL were increased significantly (P ＜0.01),while concentrations of IL-2,TNF-α,IFN-γ and IL-4 decreased obviously (P ＜0.01).In patients after chemotherapy,concentrations of H2S and IL-10 were decreased significantly (P ＜0.05),but IL-4 and IFN-γ concentrations increased markedly (P ＜0.05).At remission stage,H2S,IL-13,IL-4,IL-6,IL-10 and MIP-1α concentrations were further decreased markedly (P ＜0.05),but concentrations of IL-2,TNF-α and IFN-γ increased again (P ＜0.05).Protein contents of CSE,IL-10,IL-4 and IL-2 of PBMCs also increased markedly in children with ALL.Moreover,changes of CSE protein contents of PBMCs were consistent with serum H2S contents,and there were significant correlation between H2S and certain cytokines based on stepwise regression analysis.Furthermore,compared with those of PBMCs group,in vitro study indicated that Jurkat cells of H2S group expressed IFN-γ,IL-10,IL-4 and IL-2 protein increased obviously (P ＜0.05),while IL-4,IL-2 and CSE expression of PPG group decreased markedly (P ＜0.05).Conclusion Gaseous molecule H2S might participate in the process of immune regulation in pediatric ALL through modulating transcription and expression of cytokines.

Background Bacterial inflammation is a common complication in patients with leukemia,and sulfur dioxide (SO2) is a bioactive molecule in modulating Gram-negative bacilli infection.This study aimed to examine the changes in SO2,nuclear factor-κB (NF-κB),and interleukin-8 (IL-8) levels in pediatric acute lymphoblastic leukemia (ALL) with Gram-negative bacterial inflammation.Methods Fifty-five ALL children were enrolled in this study,including 30 males and 25 females,aged 3-13 years,and the median age was 7.8 years.All these children who accepted chemotherapy for ALL were divided into the control group (before chemotherapy),the infection group (after chemotherapy with infection),and the recovery group (the infection was controlled after 1 week).The serum level of SO2 was detected using high performance liquid chromatography with fluorescence assay,and NF-κB and IL-8 levels were measured by enzyme-linked immunosorbent assay (ELISA).Human THP-1 cells were cultured,induced,and differentiated into macrophages,which were divided into five groups and each group was cultured with different stimulators:lipopolysaccharide (LPS) group,LPS+L-aspartate-β-hydroxamate (HDX) group,LPS+SO2 group,SO2,and control groups.NF-κB level and IL-8 protein contents by ELISA were examined in each group.Results In comparison with those of the control group,levels of serum SO2,NF-κB,and IL-8 of the infection group were significantly increased (P ＜0.05),while those of the recovery group were significantly decreased (P ＜0.05).A positive correlation was found between levels of serum SO2 and intracellular NF-κB/IL-8,and the correlation coefficients were 0.671 and 0.798 (P ＜0.05),respectively.According to the results found in human THP-1 cells,levels of NF-κB and IL-8 in LPS group were significantly increased compared with those of the control group (P ＜0.05); when compared with those in LPS group,levels of NF-κB in LPS+HDX group further increased significantly (P ＜0.05); however,the NF-κB levels of LPS+SO2 group decreased significantly (P ＜0.05).Conclusion SO2 may play an anti-inflammatory role during the process of inflammation by inhibiting the activation and transcription of NF-κB.

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

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

We stimulated preadipocyte of mice with calcium acetate, p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB203580, the paralysors and excitomotors of calcium channel. Then we detected expression level of preadipocyte differentiation's marker genes and calcium signal related acceptor genes by real-time PCR, and determined intracellular free Ca2+ concentration ([Ca2+]i]) with Fura-2/AM, intracellular lipid accumulation by oil red O staining. Our aim was to investigate the potential mechanism between calcium signal and preadipocyte differentiation. The results indicated that the paralysors and excitomotors of calcium channel changed the expression level of lipoprotein lipase (LPL), peroxisome proliferators-activated receptor gamma (PPARgamma), fatty acid synthetase (FAS), and the lipid accumulation, markedly. Compared with exocellular Ca2+'s decrease, inhibited intracellular Ca2+'s liberation can promoted preadipocyte differentiation (P < 0.01), and compared with intracellular Ca2+'s increase, promoted exocellular Ca2+'s ingest inhibited preadipocyte differentiation (P < 0.01). SB203580 degraded [Ca2+]i, promoted differentiation marker genes' expression and lipid accumulation in preadipocyte (P < 0.01). But calcium signal didn't have effects to vitamin D receptor (VDR) and extracellular Ca2+-sensing receptor (CaSR)'s expression. It indicated that calcium signal may effect preadipocyte different and lipid accumulation by p38 MAPK pathway.
Adipocytes ; cytology ; Animals ; Calcium ; metabolism ; Calcium Signaling ; drug effects ; Cell Differentiation ; physiology ; Cells, Cultured ; Imidazoles ; pharmacology ; Lipids ; biosynthesis ; Mice ; Pyridines ; pharmacology ; p38 Mitogen-Activated Protein Kinases ; antagonists & inhibitors

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