Copy number variation of the ZNF679 gene in cattle and its association analysis with growth traits.

Copy number variation (CNV) is an important member of genetic structural variation that exists widely in animal genomes and is between 50 bp and several Mb in length and widely used in research's of animal genetics and breeding. ZNF679 is an important transcription factor, which has been found association with diseases in the human genome many times. This gene has also been found to be associated with cattle growth traits in previous re-sequencing studies. We tested the CNVs of the ZNF679 gene in 809 individuals from 7 Chinese cattle breeds and tested the association between the CNVs and growth traits in 552 individuals from 5 breeds. The results demonstrated the correlation the correlation between the CNVs of the ZNF679 gene and some Chinese cattle (QC cattle and XN cattle) growth traits. To sum up, this study indicated that ZNF679-CNVs can be used as a candidate gene for molecular genetic marker-assisted selection breeding for cattle growth traits to contribute to the development of genetic improvement of Chinese cattle.

Bone marrow mesenchymal stem cells-derived exosomes reduce Aß deposition and improve cognitive function recovery in mice with Alzheimer's disease by activating sphingosine kinase/sphingosine-1-phosphate signaling pathway.

Exosomes are associated with the development and progression of Alzheimer's disease (AD), although the impact of these extracellular vesicles in brain pathological condition remains incompletely understood. Therefore, this study aimed to investigate the role and mechanism of exosomes signaling in AD. Double transgenic APP/PS1 mice were injected with bone marrow mesenchymal stem cells (BM-MSCs)-derived exosomes or combined with SKI-Ⅱ (sphingosine kinase [SphK] inhibitor) or VPC23019 (sphingosine-1-phosphate [S1P] 1 receptor blocker). We observed the spatial learning and memory ability of mice, and assessed the levels of amyloid and proteins. We found that exosomes improved spatial learning and memory ability of APP/PS1 mice, and enhanced the expression of SphK1 and S1P1. Moreover, exosomes inhibited the levels of amyloid and enhanced the expression of NeuN in cortex and hippocampus of APP/PS1 mice. Exosomes repressed the levels of Aß1-40, Aß1-42, BACE1, and PS1, and promoted the expression of neprilysin in APP/PS1 mice. The influence conferred by exosomes was abolished by SKI-Ⅱ or VPC23019. In conclusion, our article confirms that BM-MSCs-derived exosomes reduce Aß deposition and promote cognitive function recovery in AD mice by activating SphK/S1P signaling pathway. Thus, our data suggest that S1P/SphK-containing exosomes should be explored as potential AD cure.

Effects of rosuvastatin correlated with the down-regulation of CYP4A1 in spontaneously hypertensive rats.

The effects of long-term rosuvastatin treatment on the regulation of cytochrome P450 (CYP) 4A1 expression and vascular homeostasis of spontaneously hypertensive rat (SHR) are still unknown. In this study SHRs were randomly divided into three groups (n=10 per group): SHR group, H-Rv group (rosuvastatin 2.5 mg·kg(-1)·d(-1)), L-Rv group (rosuvastatin 0.5 mg·kg(-1)·d(-1)), and 10 male Wistar-Kyoto (WKY) rats in the control group (WKY group). All rats were treated with rosuvastatin for 12 weeks. The systolic blood pressure (SBP), left ventricle weight index (LVWI) and plasma lipids were measured during or after treatment. The expression of CYP4A1 mRNA and protein in different tissues was detected by real-time PCR and Western blot. In the heart, kidney and aorta, the CYP4A1 expressions were down-regulated at both mRNA and protein levels in rosuvastatin-treated groups compared with the untreated SHR group (P<0.05 or P<0.01), and high-dose rosuvastatin exerted a stronger down-regulatory effect. The increasing trend of blood pressure was markedly blunted in the rosuvastatin-treated groups versus the untreated SHR group, and a stronger effect was observed in high-dose group (P<0.05 and P<0.01 at different time points). LVWI, an indicator of ventricle hypertrophy, was improved in the high-dose group compared with the untreated SHR group (P<0.05). The plasma concentrations of TC, TG and LDL-C in three SHR groups (high-dose, low-dose and untreated group) were all significantly lower than those of WKY group (P<0.05 or P<0.01), which seemed unrelated to the treatment of rosuvastatin. These findings suggested that hypertension in SHRs was possibly associated with CYP4A1 overexpression, and the effects of rosuvastatin on blood pressure and ventricle hypertrophy were potentially correlated with CYP4A1 and its metabolite other than lipid profiles. Multiple mechanisms are likely involved in the beneficial effects of statins with respect to the regulation of CYP4A1.

The relationship between MFN1 copy number variation and growth traits of beef cattle.

Copy number variation, as a kind of genetic submicroscopic structural variation, refers to the deletion or repetition of a large segment of genomic DNA, involving a segment size ranging from 50 bp to several MB. Mitochondrial fusion protein (MFN1) gene regulates the fusion of mitochondrial outer membrane in cells and maintains the dynamic needs of reticular mitochondria in cells. In this study, we conducted to tested the dstribution characteristics of MFN1-CNV in 522 cattles across Xianan cattle (XN), Pinan cattle (PN), Qinchuan cattle (QC), Jiaxian cattle (JX), Yunling cattle (YL), and correlated it with phenotypic traits. Then we observed the expression of MFN1 in various tissues of QC cattle (n = 3), and the expression levels were higher in lung and muscle. The results showed that there was significant correlation between MFN1 gene CNV and hucklebone width of QC cattle, hip width and height at sacrum of JX red cattle, chest width and rump length of YL cattle (P < 0.05). Individuals with duplication type were better than the type of normal or deletion in phenotypic traits. In conclusion, our data showed the correlation between MFN1 gene and growth traits of Chinese cattle. MFN1 gene can be used as a molecular marker for cattle selection and breeding, and accelerate the improvement of Chinese cattle.

The copy number variation of DMBT1 gene effects body traits in two Chinese cattle breeds.

Copy number variations (CNVs) belong to mutations in the genome level with loci in the region of genic or intergenic. It is through different effects (such as position effect and dose effect) that influence complex traits and diseases. Deleted in Malignant Brain Tumors 1 (DMBT1) gene is a member of the scavenger receptor cysteine-rich super family. In cattle, this gene has been associated with the susceptibility to bovine tuberculosis. In this study, a new CNV was found in DMBT1 gene of Chinese cattle breeds and tested in two different Chinese cattle breeds (Jiaxian red and Pinan) for frequency distribution analysis. Besides, the body size data such as body length, body height, chest girth, chest width, rump length, and rump girth for Jiaxian (JX) and Pinan (PN) cattle were collected and associated with the newly identified CNV. The CNV was significantly associated with the body length and chest girth of JX cattle, and the rump length of PN cattle (P < 0.05). Furthermore, the expression profile of the DMBT1 gene was tested in calves' tissues and the myoblasts differentiation. It was found that the DMBT1 gene expression was high in tuberculosis susceptible tissues (liver and lungs) at the calf stage and high in myoblast early differentiation. These tests were done using the qPCR method. As the result, the CNV of DMBT1 gene could be used as a candidate marker for bovine growth and health in marker-assisted selection (MAS) breeding.

Effect of copy number variation of PLA2G2A gene to growth traits in Chinese cattle.

SIMPLE SUMMARY: As a member of genetic polymorphism, copy number variation has been a commonly used method in the world for investigating effect of genetic polymorphism on gene expression. Effect of genetic polymorphism made on livestock development has been more and more important in beef cattle molecular breeding. The characteristics of Chinese cattle are excellent meat quality, tolerant to rough feeding, good environmental adaptability and so on. But there are some obvious weaknesses still exist in the process of cattle growth and development, such as weak hindquarters and growth slowly. To improve the growth performance and market competitiveness of Chinese cattle, a lot of studies have been made about finding and investigating effective molecular marker. In this study, Q-PCR and data association analysis were used for PLA2G2A gene copy number variation detection and related effect analysis in Chinese cattle. Results showed that PLA2G2A gene has a significant effect on two breeds of Chinese cattle on growth traits, which could be a basic materials and effective information of cattle molecular markers breeding. PLA2G2A, member of secreted phospholipases A2 (sPLA2) in superfamily of phospholipase A2, could catalyze the process of glycerophospholipids hydrolysis from position of sn-2 acyl with the release of free fatty acids and lysophospholipids. Researches about PLA2G2A gene are mostly focus on disease, including tumors and diabetes, the number of study occurred on animal breeding is weak. In this study, blood samples were collected from five breeds of Chinese cattle (Qingchuan cattle, Xianan cattle, Yunling cattle, Pinan cattle and Guyuan cattle) for PLA2G2A gene CNV type detection. SPSS 20.0 software and method of ANOVA were used to analyzed the association between types of CNV and growth traits. Results reveal that the distribution of different copy number types in different cattle breeds is different. In QC, XN and GY cattle, the frequencies of Deletion and Duplication are about 40%; in YL cattle, the frequency of Deletion type exceeds 60%; in PN cattle, the frequency of Duplication is closed to 80%. Association analysis indicate that CNV of PLA2G2A gene showed a positive effect in cattle growth: in QC cattle, Chest depth with Normal type copy number possess a increased trend (P < 0.05); individuals with Deletion type copy number have better performance on Height at sacrum, Heart girth and Body height in GY cattle (P < 0.05). The functional role and molecular mechanism of PLA2G2A gene in animal growth and development are still unclear, and it is necessary for processing a further research. This research aims to provide basic materials for molecular breeding of Chinese cattle.

Copy number variation of EIF4A2 loci related to phenotypic traits in Chinese cattle.

BACKGROUND: Generally, copy number variation (CNV) is a large-scale structural variation between 50 bp and 1 kb of the genome. It can affect gene expression and is an important reason for genetic diversity and phenotypic trait diversity. Studies have shown that the eukaryotic translation initiation factor 4A2 (EIF4A2) gene plays an essential role in muscle development in both humans and pigs. However, the influence of bovine EIF4A2's copy number change on phenotypic traits has not been reported. OBJECTIVES: To detect the tissue expression profile of the EIF4A2 gene in adult cattle and individuals' CNV type of variation. Then, we explored the correlation between EIF4A2-CNV and growth traits in Chinese cattle breeds. METHODS: Real-time fluorescent quantitative reverse transcription PCR (qRT-qPCR) was used to determine the expression profile of the EIF4A2 gene. Real-time fluorescent quantitative PCR (qPCR) was used to detect the CNV type of bovine populations. Then, SPSS 26.0 was used for association analysis. RESULTS: In this study, a total of 513 individuals in four cattle breeds (Qinchuan cattle [QC], Yunling cattle [YL], Pinan cattle [PN] and Jiaxian cattle [JX]) were detected for EIF4A2 gene's CNV. The results showed that EIF4A2-CNV has an essential impact on hip width (HW) and rump length (RL) in QC, heart girth (HG), chest depth (CD) and RL in YL and HW in PN. However, it had no significant effect on JX. CONCLUSIONS: The above results suggest that EIF4A2 gene's CNV can be used as a molecular marker for cattle breeding, which is helpful to accelerate the breeding of superior beef cattle breeds.

M2 macrophage-derived exosomes carry miR-1271-5p to alleviate cardiac injury in acute myocardial infarction through down-regulating SOX6.

BACKGROUND: Emerging evidence has indicated that exosomes serve as key regulators in acute myocardial infarction (AMI). This study was determined to investigate the effect of M2 macrophage-derived exosomes (M2-Exos) in AMI and the further mechanism. METHODS: M2 macrophages were induced and M2-exos were isolated and verified. The AMI mouse model was prepared by ligation of the left anterior descending coronary artery (LAD) and then intravenously injected with the isolated M2-exos. The mouse cardiac function was assessed by echocardiography. Hematoxylin and eosin (HE) staining and TUNEL assay were conducted to examine myocardial lesion and apoptosis in cardiac tissues. The expressions of associated molecules were detected by quantitative real time-PCR (qRT-PCR) and western blot. MTT assay, Flow cytometry and Dual-luciferase reporter assay were carried out to detect cell viability, apoptosis and the interaction of miRNA and the target. RESULT: M2-Exos could promote cardiac repair in AMI mice. M2-Exos suppressed apoptosis and enhanced viability of hypoxia-induced cardiomyocytes through delivery of miR-1271-5p. SOX6 is a direct target of miR-1271-5p. miR-1271-5p decreased cardiomyocyte apoptosis induced by hypoxia and alleviated cardiac injury in AMI via down-regulating SOX6 expression. CONCLUSION: We identified that M2-Exos could carry miR-1271-5p to reduce apoptosis of cardiomyocytes and promote cardiac repair via down-regulating SOX6.

Development and validation of a simple risk model to predict major cancers for patients with nonalcoholic fatty liver disease.

OBJECTIVE: To recognize risk factors and build up and validate a simple risk model predicting 8-year cancer events after nonalcoholic fatty liver disease (NAFLD). METHODS: This was a retrospective cohort study. Patients with NAFLD (n = 5561) were randomly divided into groups: training (n = 1254), test (n = 627), evaluation (n = 627), and validation (n = 3053). Risk factors were recognized by statistical method named as a Cox model with Markov chain Monte Carlo (MCMC) simulation. This prediction score was established based on the training group and was further validated based on the testing and evaluation group from January 1, 2007 to December 31, 2009 and another 3053 independent cases from January 1, 2010 to February 13, 2014. RESULTS: The main outcomes were NAFLD-related cancer events, including those of the liver, breast, esophagus, stomach, pancreas, prostate and colon, within 8 years after hospitalization for NAFLD diagnosis. Seven risk factors (age (every 5 years),LDL, smoking, BMI, diabetes, OSAS, and aspartate aminotransferase (every 5 units)) were identified as independent indicators of cancer events. This risk model contained a predictive range of 0.4%-37.7%, 0.3%-39.6%, and 0.4%-39.3% in the training, test, evaluation group, respectively, with a range 0.4%-30.4% for validation groups. In the training group, 12.6%, 76.9%, and 10.5% of patients, which corresponded to the low -, moderate -, and high-risk groups, had probabilities of, <0.01, <0.1, and 0.23 for 8-year events. CONCLUSIONS: Seven risk factors were recognized and a simple risk model were developed and validated to predict the risk of cancer events after NAFLD based on 8 years. This simple risk score system may recognize high-risk patients and reduce cancer incidence.

Effect of testosterone on the proliferation and collagen synthesis of cardiac fibroblasts induced by angiotensin II in neonatal rat.

The objective is to explore the effect of testosterone on the proliferation and collagen synthesis of neonatal rat cardiac fibroblasts (CF) induced by Angiotensin II (Ang II) and the underlying mechanisms. Derived from neonatal rats, the CFs were divided into 4 groups: the control group, Ang II group, testosterone group, and testosterone + Ang II group in vitro. Cell cycle distribution, collagen counts, and phosphorylated extracellular signal-regulated kinase (ERK1/2) (p - ERK1/2) expression were assessed by flow cytometry, VG staining, and immunocytochemistry, respectively. The Ang II group had a much higher proportion of cells in the S-phase, higher collagen contents, and a higher p - ERK1/2 expression level than either the control or testosterone group. However, these factors were significantly reduced in the testosterone + Ang II group as compared to the Ang II group. In terms of cells in the S-phase and the collagen contents, there was not a significant difference between the testosterone group and the control. However, the protein expression of p-ERK1/2 was significantly increased in the testosterone group as compared to the control. Testosterone inhibits the proliferation and collagen synthesis of CF induced by Ang II. The underlying mechanism may involve the ERK1/2 signaling pathway.

Regulation on RhoA in vascular smooth muscle cells under inflammatory stimulation proposes a novel mechanism mediating the multiple-beneficial action of acetylsalicylic acid.

Recent studies have revealed the additional beneficial effects of acetylsalicylic acid (aspirin) in the medication of cardiovascular diseases. The small GTPase RhoA as an important signaling factor is implicated in a wide range of cell functions. This study aimed to investigate the regulatory effect of acetylsalicylic acid on RhoA in vascular smooth muscle cells (VSMCs). We found that aspirin at 300 µM suppressed VSMCs proliferation stimulated by LPS, and this inhibitory effect was partially mediated by inhibiting the iNOS/NO pathway. RhoA overexpression was downregulated by aspirin (both 30 and 300 µM) because of enhanced degradation of RhoA protein. The effect of LPS on increasing active RhoA level was significantly attenuated by aspirin (300 µM), which exerted no effect on RhoA translocation. The promoted RhoA phosphorylation under LPS stimulation, coupled with RhoA protein expression, was greatly decreased by aspirin treatment. No effect of aspirin was found on the expression, activation, and phosphorylation of RhoA in VSMCs devoid of inflammatory stimulation. Our investigation indicates that the regulation of RhoA by aspirin in VSMCs under inflammatory stimulus could be a novel mechanism via which aspirin, apart from the COX-dependent action, exerted the multiple beneficial effects.