Impact of Bovine Skeletal Muscle Satellite Cell Differentiation by Small Interfering RNA Targeting Myogenin Gene

To examine the effect of myogenin gene on the differentiation of bovine skeletal muscle satellite cell, we constructed small interfering RNA plasmid vector to obtain myogenin knockdown bovine skeletal muscle cells, then used cell transfection, real time RCR and Western Blot to detect the influence of myogenin to cell differentiation. Results showed that the knockdown of myogenin significantly decreased its expression and other muscle-specific genes. Compared to the control, it could differentiate into few myotubes when challenged by low serum in the medium. These findings provided an important theoretical basis for further explore of the genetic mechanism in adult skeletal muscle, the remedy of muscle injuries and the cultivation of high-yield transgenic cattle.

Galactopoietic Activity of Dibutyl Phthalate Isolated from Vaccaria segetalis

A galactopoietic compound, identified as dibutyl phthalate（DBP）, was isolated from Vaccaria segetalis. The activity of DBP on lactation ability of dairy cow mammary gland epithelial cells（DCMECs） cultured in vitro and dairy cow was evaluated. Results showed that DBP could promote cell viability, proliferation ability, lactose and β-casein secretion of DCMECs, which could also raise the milk yields of dairy cows significantly.

GDM并发重度子痫前期孕妇糖脂代谢及妊娠结局分析

目的研究妊娠期糖尿病(GDM)并发重度子痫前期(sPE)孕妇的糖脂代谢情况及妊娠结局。方法选取渭南市妇幼保健院2019年2月至2020年6月期间收治的40例GDM并发sPE孕妇作为研究组,另选取同期接诊的40例单纯GDM孕妇作为对照组。在入院时记录两组孕妇的总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、空腹血糖(FBG)、糖化血红蛋白(HBA1c)、白蛋白(ALB)、空腹胰岛素(FINS)等糖脂代谢指标,并比较两组孕妇的妊娠结局。结果两组孕妇入院时的HbAIc、TC、TG、HDL-C、LDL-C水平比较差异均无统计学意义(P<0.05);研究组孕妇的FBG、FINS水平分别为(5.6±0.5)mmol/L、(147.8±32.7)pmol/L,明显高于对照组的(4.3±0.4)mmol/L、(89.4±15.4)pmol/L,ALB水平为(28.3±0.7)g/L,明显低于对照组的(32.7±0.9)g/L,差异均有统计学意义(P<0.05);研究组孕妇的分娩孕周、新生儿体质量、自然分娩率分别为(35.8±2.4)周、(3.1±0.8)kg、67.5%,明显低于对照组的(39.4±3.1)周、(3.5±0.6)kg、37.5%,产后出血量为(421.6±125.3)mL,明显高于对照组的(316.6±131.5)mL,差异均有统计学意义(P<0.05);研究组孕妇的不良妊娠结局发生率为30.0%,明显高于对照组的10.0%,差异有统计学意义(P<0.05)。结论GDM并发sPE孕妇存在更为严重的糖脂代谢异常,产后出血量更多,不良妊娠结局发生率更高,应加强对孕妇的孕期监测,从而有效改善妊娠结局。

The Effects of Insulin and Prolactin on an Epithelial Cell Line from Mammary Gland of Dairy Goat

Mammary epithelial cells with lactational function can be a valuable cellular model for research of the development and regulation of the mammary gland.This paper describes some aspects of function of an epithelial cell line from the mammary gland of the dairy goat.SDS-PAGE,triglyceride and lactose content of cultured cells were used to assess synthetic function of cells and the effects of exposure to insulin and prolactin.Results show that goat mammary epithelial cells can synthesize fat,proteins and lactose when they were cultured in DMEM-F12 medium with added EGF,IGF-1,ITS and FBS.There were no obvious changes after 48h treatment with additional insulin.Prolactin added to the basal medium significantly increased synthesis of proteins and lactose.A mammary gland epithelial cell line from goats which has lactational function has been established.This outcome provides a valuable and convenient model system.

Contents of Trace Metal Elements in Cow Milk Impacted by Different Feedstuffs

Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb, Cd, As, Cu, Mg, Ca, Fe and Zn in different feedstuffs and milk by atomic absorption spectrophotometry. The determinations of Pb, Cd and As contents were by graphite furnace A_AS and Cu, Mg, Ca, Fe and Zn was by flame atomic absorption spectrometry. The results showed that Pb, Cd, As and Cu presented in feedstuffs, but Pb, Cd and As were lowly detected in milk samples, and Cu was not detected in milk samples. The content of Mg in concentrates was lower than that in forages. However, the content of Mg in milk from concentrate feed was higher than that in forage feed. This suggested that the utilization of Mg in concentrate feed was higher than that in forage feed. The contents of Ca and Zn were opposite to Mg, and the utilization of Ca and Zn in forage feed was higher than that in concentrate feed. There was no obviously change law of Fe in different feedstuffs and milk samples. The relationship between the contents of trace metal elements in milk to feedstuffs would provide a theoretical basis for dairy farming. It would be useful for improving the milk yield and milk quality of dairy production.

Effect of MSTN Propeptide and shRNA Co-expression Vector on Proliferation of Skeletal Muscle Satellite Cells

Myostatin （MSTN） is a negative regulator of skeletal muscle growth, in order to study the effect of inhibition MSTN expression on the proliferation of bovine skeletal muscle satellite cells, we constructed co-expression vector pcDNA3.1-Pro- MSTNshRNA, transfected it into muscle satellite cells by Liposome 2000, and detected cell proliferation changes by CCK-8 method and flow cytometry after 48 h. The expressions of P21 and CDK2 were detected by Western blot and real-time PCR. The results showed that the cell vitality of experimental groups significantly increased than that of the negative control, and cells in S phase also increased significantly （P〈0.05）. After knocked down MSTN gene, P21 expression decreased （P〈0.05）, but CDK2 gene expression increased （P〈0.05）. These results indicated that MSTN gene expression was associated with P21 and CDK2, the proliferation of skeletal muscle satellite cells could be promoted while MSTN was inhibited, which provided a theoretical basis for the study on transgenic cattle.

Effects of DHRS3 in C2C12 Myoblast Differentiation and Mouse Skeletal Muscle Injury

Myoblast differentiation is an essential process during skeletal muscle development.C2C12 myoblast is a commonly used experimental model to study muscle cell differentiation in vitro.Dehydrogenase/reductase(SDR family)member 3(DHRS3)is a highly conserved member in short-chain alcohol dehydrogenase/reductase superfamily and has been shown to be involved in the metabolism of retinol.Previous experimental results showed that the expression of DHRS3 increased significantly during the differentiation of myoblasts differentiation.However,the effect of DHRS3 on mouse muscle cell differentiation was unclear.The objective of current study was to determine if DHRS3 affected muscle cell differentiation,and if DHRS3 was involved in muscle regeneration.Protein expression was determined by western blot and immunofluorescence analysis.The activation and inhibition of DHRS3 increased and decreased C2C12 myoblast differentiation respectively,which indicated that DHRS3 could affect C2C12 myoblast differentiation.DHRS3 expression was significantly changed during muscle regeneration,with the regeneration of muscle injury,the expression of DHRS3 tended to increase first and then decrease.It suggested that DHRS3 might be involved in muscle regeneration.In summary,this study confirmed the involvement of DHRS3 in C2C12 myoblast differentiation and mouse skeletal muscle regeneration and provided a theoretical basis for further elucidating the molecular mechanism of muscle development.

Research Progress of Vitamins on Muscle Regeneration

Muscle satellite cells,as muscle stem cells,play a critical role in the process of muscle regeneration,and effective muscle regeneration helps to restore muscle function and maintain the homeostasis of muscle tissues.In damaged muscle,muscle satellite cells are activated to form new myofibers through the process of cell proliferation,migration,differentiation and fusion to complete muscle tissue regeneration.Meanwhile,this process is mainly affected by endogenous gene expression and many exogenous factors.Researches in recent years have shown that vitamins,as important nutrients,play an extremely important role in the process of muscle regeneration.Therefore,this article reviewed the roles of vitamins in the regeneration of muscle satellite cells,according to the latest research progress.It would provide more theoretical and data support for the regeneration and repair of muscle damage,muscle atrophy and other muscle diseases,so that it could be better applied in the field of muscle regeneration researches and serve human health.