👤 Song Zhu

Pancreatic cancer (PC) is among the most aggressive types of cancer. Hypoxia has been identified as a key risk factor for cancer progression. The forkhead box (FOX) proteins are multidirectional transcriptional factors that are strongly implicated in malignancies. However, whether FOXO3a, a member of the FOX protein family, is involved in the pro-oncogenic functions of hypoxia in PC has remained largely unelucidated. In this study, we attempted to clarify the role of FOXO3a in metastasis under hypoxic conditions and its underlying mechanism. MTT and flow cytometry assays were performed to detect the cell proliferation and cell cycle distribution respectively. Transwell assays were used to determine the potential of cell migration and invasion. qPCR and western blot assays were used to assess the expression of mRNA and protein. Immunofluorescence assay was performed to evaluate the cellular localization of FOXO3a. FOXO3a overexpression plasmid was constructed to perform the rescue experiment. Our data indicated that PANC-1 and SW1990 cells represented enhanced cell migration and invasion abilities under hypoxia, while no statistical differences in cell proliferation and cell cycle distribution were observed. Hypoxia upregulated the messenger RNA (mRNA) and protein expressions of HIF-1α, FOXO3a, and the key epithelial-mesenchymal transition (EMT)-related (EMT) molecules N-cadherin and vimentin, as well as the phosphorylation of FOXO3a. Interestingly, hypoxia promoted the extranuclear localization of FOXO3a. Overexpression of FOXO3a not only significantly decreased the invasion, migration, and EMT of PC cell lines, but also reversed hypoxia-induced extranuclear localization. Finally, FOXO3a might act as a tumor suppressor in PC by inhibiting the ERK signaling pathway by inducing DUSP6 expression, and the ERK activator fisetin could effectively attenuate the inhibitory role of FOXO3a on ERK. Taken together, our results identified that hypoxia-induced extranuclear localization of FOXO3a promoted cell migration and invasion of human PC by modulating the DUSP6/ERK pathway. Show less

Endometriosis (EM) is a benign gynecological disease that shares some characteristics with malignancy, such as proliferation and invasion. So far, the pathogenesis of EM is still unclear. In this study, we investigated whether TRIM65 can play a role in the development of EM. TRIM65 expression levels in eutopic, ectopic, and normal endometrium were detected by quantitative real-time PCR and Western blot. Cell proliferation and invasion of primary endometrial stromal (EMS) cells were detected by CCK-8 and Transwell analysis. The interaction between TRIM65 and DUSP6 or C-myc was measured by coimmunoprecipitation, ubiquitylation, dual luciferase, and chromatin immunoprecipitation analysis. We found that TRIM65 was identified as an up-regulated gene in ectopic endometrial tissues and EMS cells compared with control groups without EM. TRIM65 expression was positively correlated with the levels of p-ERK1/2, C-myc, matrix metalloproteinase-2, and integrin β1 in ectopic endometrial tissues in patients and mice. TRIM65 promoted the cell proliferation and invasion of EMS cells via the ERK1/2/C-myc pathway through ubiquitination of DUSP6. C-myc promoted TRIM65 expression through inducing TRIM65 promoter activity. Additionally, the increased expression of TRIM65, C-myc, matrix metalloproteinase-2, integrin β1, and p-ERK1/2 and the decreased expression of DUSP6 in ectopic endometrial tissues were significantly suppressed by inhibition of ERK1/2 signaling pathway in ectopic endometrial tissues in experimental mice model. In conclusion, TRIM65 promotes invasion of ectopic EMS cells by activating a feedback loop with the ERK1/2/C-myc signaling pathway and may be a potential therapeutic target for EM. Show less

Chordoma is a rare bone cancer with an unknown etiology. TBXT is the only chordoma susceptibility gene identified to date; germline single nucleotide variants and copy number variants in TBXT have been associated with chordoma susceptibility in familial and sporadic chordoma. However, the genetic susceptibility of chordoma remains largely unknown. In this study, we investigated rare germline genetic variants in genes involved in TBXT/chordoma-related signaling pathways and other biological processes in chordoma patients from North America and China. We identified variants that were very rare in general population and internal control datasets and showed evidence for pathogenicity in 265 genes in a whole exome sequencing (WES) dataset of 138 chordoma patients of European ancestry and in a whole genome sequencing (WGS) dataset of 80 Chinese patients with skull base chordoma. Rare and likely pathogenic variants were identified in 32 of 138 European ancestry patients (23%), including genes that are part of notochord development, PI3K/AKT/mTOR, Sonic Hedgehog, SWI/SNF complex and mesoderm development pathways. Rare pathogenic variants in COL2A1, EXT1, PDK1, LRP2, TBXT and TSC2, among others, were also observed in Chinese patients. We identified several rare loss-of-function and predicted deleterious missense variants in germline DNA from patients with chordoma, which may influence chordoma predisposition and reflect a complex susceptibility, warranting further investigation in large studies. Show less

Hereditary multiple exostoses (HME) is a rare skeletal disorder characterized by the formation of multiple benign cartilage-capped tumors, usually in the metaphyseal region of the long bones. Over 70% of HME cases arise from monoallelic mutations in either of the two genes encoding the heparan sulfate (HS) synthesis enzymes, ext1 and ext2. To identify more HME-associated mutations, genomic DNA from members of five independent consanguineous families with HME was sequenced with whole exome sequencing (WES). A novel heterozygous splice site mutation (c.1173+2T>A) in ext2 was detected in all three affected members of family V. Further study showed that the novel mutation caused exon 7 of ext2 mRNA to be skipped during splicing and caused a frameshift after the codon for Arg360, which results in the appearance of new 43 codons, followed by a termination codon. Although the resulting truncated protein was still localized to the Golgi, similar to the full-length EXT2, its HS synthesis activity decreased by 40%. In this study, a novel splice site mutation in ext2 was identified and suggested to be a pathogenic mutation of HME, which may expand the genetic etiology spectrum of HME and may be helpful for clinical genetic counseling and prenatal diagnosis. Show less

Microribonucleic acid-155 (microRNA155) and microRNA29 are reported to inhibit glucose metabolism in some cell and animal models, but no evidence from susceptible populations that examines the relationship between microRNA155 or microRNA29 and type 2 diabetes mellitus currently exists. Furthermore, target genes regulated by microRNA155 and microRNA29 that affect glucose and lipid metabolism remain unknown. Human participants were divided into normal weight (n = 72), obesity (n = 120) and type 2 diabetes (n = 59) groups. The contents of microRNA155 and microRNA29 abundance in serum were measured, and candidate genes potentially related to glucose and lipid metabolism targeted by either microRNA155 or microRNA29 were screened. Overexpression of microRNA155 and microRNA29 in HepG2 cells was used to verify candidate gene expression, and measure the effects on glucose and lipid metabolism. Serum levels of microRNA155 and microRNA29 show a significant increase in individuals with obesity and type 2 diabetes compared with normal weight individuals. Identified target genes for microRNA155 were MAPK14, MAP3K10, DUSP14 and PRKAR2B. Identified target genes for microRNA29 were PEX11A and FADS1. Overexpression of microRNA155 or microRNA29 in HepG2 cells was found to downregulate the expression of identified target genes, and result in inhibition of triglyceride synthesis and glucose incorporation. MicroRNA155 and microRNA29 were significantly higher in type 2 diabetes patients compared with the control patients, their levels were also positively correlated with fasting plasma glucose levels, and over-expression of microRNA155 or microRNA29 were found to downregulate glucose and lipid metabolism target genes, and reduce lipid synthesis and glucose incorporation in HepG2 cells. Show less

To explore the genetic basis for a sib pair featuring 17beta-hydroxysteroid dehydrogenase type 3 deficiency. Genomic DNA was extracted from the proband, her sister, and their parents, and was subjected to sequencing analysis with a gene panel for sexual development. Suspected variant was verified by Sanger sequencing and bioinformatic analysis. Both the proband and her sister were found to harbor novel compound heterozygous missense variants of the HSD17B3 gene, namely c.839T>C (p.Leu280Pro) and c.239G>T (p.Arg80Leu), which were derived respectively from their mother and father. The variants were unreported previously and predicted to be deleterious by PolyPhen2, MutationTaster and other online software. Based on the American College of Medical Genetics and Genomics standards and guidelines, both c.839T>C(p.Leu280Pro) and c.239G>T (p.Arg80Leu) were predicted to be likely pathogenic (PM2+PP1+PP2+PP3+PP4, PM2+PM5+PP1+PP2+PP3+PP4). The compound heterogeneous variants of the HSD17B3 gene probably underlay the disease in this sib pair. 17beta-hydroxysteroid dehydrogenase type 3 deficiency may lack specific clinical features and laboratory index, genetic testing can facilitate a definitive diagnosis. Show less

The IL family of cytokines participates in immune response and regulation. We previously found that soluble IL-6 receptor plays an important role in the host antiviral response. In this study, we detected the IL-6-IL-27 complex in serum and throat swab samples from patients infected with influenza A virus. A plasmid expressing the IL-6-IL-27 complex was constructed to explore its biological function. The results indicated that the IL-6-IL-27 complex has a stronger antiviral effect than the individual subunits of IL-6, IL-27A, and EBV-induced gene 3. Furthermore, the activity of the IL-6-IL-27 complex is mainly mediated by the IL-27A subunit and the IL-27 receptor α. The IL-6-IL-27 complex can positively regulate virus-triggered expression of IFN and IFN-stimulated genes by interacting with adaptor protein mitochondrial antiviral signaling protein, potentiating the ubiquitination of TNF receptor-associated factors 3 and 6 and NF-κB nuclear translocation. The secreted IL-6-IL-27 complex can induce the phosphorylation of STAT1 and STAT3 and shows antiviral activity. Our results demonstrate a previously unrecognized mechanism by which IL-6, IL-27A, and EBV-induced gene 3 form a large complex both intracellularly and extracellularly, and this complex acts in the host antiviral response. Show less

To evaluate the value of interleukin (IL)-27 measured in serum and bronchoalveolar lavage fluid (BALF) for the diagnosis of smear-negative pulmonary tuberculosis (TB). This was a prospective study of patients planned to undergo bronchoscopy at Wuxi No.5 People's Hospital between January 2017 and September 2018. The patients were grouped as the TB and control groups. BALF and serum IL-27 were measured by ELISA. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value and calculate the optimal cutoff values. There were 40 patients in the control group and 87 in the TB group. In the TB group, 20 had positive sputum smear results and 67 were negative. The area under the ROC curve (AUC) of BALF IL-27 for pulmonary TB was 0.897 (95% CI: 0.830-0.944) (P < .001). The AUC of serum IL-27 for pulmonary TB was 0.703 (95% CI: 0.616-0.781) (P < .001). In patients with negative sputum smear results, the AUCs of BALF IL-27 and serum IL-27 for pulmonary TB was 0.882 (95% confidence interval [CI]: 0.805-0.936) (P < .001) and 0.679 (95% CI: 0.601-0.782) (P < .001), respectively. BALF IL-27 can be used for the diagnosis of pulmonary TB, particularly in those with a negative sputum smear result. Serum IL-27 could be an auxiliary method for TB screening. Show less

Previous genotyping-based assays have identified non-coding variants of several interleukins (ILs) being associated with genetic susceptibility to leprosy. However, understanding of the involvement of coding variants within all IL family genes in leprosy was still limited. To obtain the full mutation spectrum of all ILs in leprosy, we performed a targeted deep sequencing of coding regions of 58 ILs genes in 798 leprosy patients (age 56.2 ± 14.4; female 31.5%) and 990 healthy controls (age 38.1 ± 14.0; female 44.3%) from Yunnan, Southwest China. mRNA expression alterations of ILs in leprosy skin lesions or in response to M. leprae treatment were estimated by using publicly available expression datasets. Two coding variants in IL27 (rs17855750, p.S59A, p = 4.02 × 10 Show less

In view of the negative regulatory effect of leucine-rich repeat and immunoglobulin-like domain-containing nogo receptor-interacting protein 1 (LINGO-1) on neurons, an antibody against LINGO-1 (anti-LINGO-1 antibody) was herein administered to 10-month-old APP/PS1 transgenic Alzheimer's disease (AD) mice for 2 months as an experimental intervention. Behavioral, stereology, immunohistochemistry and immunofluorescence analyses revealed that the anti-LINGO-1 antibody significantly improved the cognitive abilities, promoted adult hippocampal neurogenesis (AHN), decreased the amyloid beta (Aβ) deposition, enlarged the hippocampal volume, and increased the numbers of total neurons and GABAergic interneurons, including GABAergic and CCK-GABAergic interneurons rich in cannabinoid type 1 receptor (CB1R), in the hippocampus of AD mice. In contrast, this intervention significantly reduced the number of GABAergic interneurons expressing LINGO-1 and CB1R in the hippocampus of AD mice. More importantly, we also found a negative correlation between LINGO-1 and CB1R on GABAergic interneurons in the hippocampus of AD mice, while the anti-LINGO-1 antibody reversed this relationship. These results indicated that LINGO-1 plays an important role in the process of hippocampal neuron loss in AD mice and that antagonizing LINGO-1 can effectively prevent hippocampal neuron loss and promote AHN. The improvement in cognitive abilities may be attributed to the improvement in AHN, and in the numbers of GABAergic interneurons and CCK-GABAergic interneurons rich in CB1Rs in the hippocampus of AD mice induced by the anti-LINGO-1 antibody. Collectively, the double target effect (LINGO-1 and CB1R) initiated by the anti-LINGO-1 antibody may provide an important basis for the study of drugs for the prevention and treatment of AD in the future. Show less

LINGO-1 may be involved in the pathogenesis of cerebral ischemia. However, its biological function and underlying molecular mechanism in cerebral ischemia remain to be further defined. In our study, middle cerebral artery occlusion/reperfusion (MACO/R) mice model and HT22 cell oxygen-glucose deprivation/reperfusion (OGD/R) were established to simulate the pathological process of cerebral ischemia in vivo and in vitro and to detect the relevant mechanism. We found that LINGO-1 mRNA and protein were upregulated in mice and cell models. Down-regulation LINGO-1 improved the neurological symptoms and reduced pathological changes and the infarct size of the mice after MACO/R. In addition, LINGO-1 interference alleviated apoptosis and promoted cell proliferation in HT22 of OGD/R. Moreover, down-regulation of LINGO-1 proved to inhibit nuclear translocation of p-NF-κB and reduce the expression level of p-JAK2 and p-STAT3. In conclusion, our data suggest that shLINGO-1 attenuated ischemic injury by negatively regulating NF-KB and JAK2/STAT3 pathways, highlighting a novel therapeutic target for ischemic stroke. Show less

Chronic stress can induce cognitive impairment, and synapse number was significantly decreased in the hippocampus of rats suffering from chronic stress. Lingo-1 is a potent negative regulator of axonal outgrowth and synaptic plasticity. In the current study, the effects of anti-Lingo-1 antibody on the spatial learning and memory abilities and hippocampal synapses of stressed rats were investigated. After 4 weeks of stress exposure, the model group was randomly divided into a chronic stress group and an anti-Lingo-1 group. Then, the anti-Lingo-1 group rats were treated with anti-Lingo-1 antibody (8 mg/kg) for 3 weeks. The effects of anti-Lingo-1 antibody on the spatial learning and memory abilities were investigated with the Morris water maze test. Immunohistological staining and an unbiased stereological method were used to estimate the total number of dendritic spine synapses in the hippocampus. At the behavioral level, after 3 weeks of treatment, the anti-Lingo-1 group rats displayed significantly more platform location crossings in the Morris water maze test than the chronic stress group rats. Anti-Lingo-1 significantly prevented the declines in dendritic spine synapses and postsynaptic density protein-95 (PSD-95) expression in the dentate gyrus and the CA1 and CA3 regions of the hippocampus. The present results indicated that anti-Lingo-1 antibody may be a safe and effective drug for alleviating memory impairment in rats after chronic stress and protecting synapses in the hippocampus of stressed rats. Show less

Aging acts as a dominating risk factor for human cancers. Herein, we systematically dissected the features of transcriptional aging-relevant genes in gastric cancer from multiple perspectives. Based on the transcriptome profiling of prognostic aging-relevant genes, patients with gastric cancer in The Cancer Genome Atlas (TCGA) stomach adenocarcinoma (TCGA-STAD) cohort were clustered with a consensus clustering algorithm. Mutational landscape and chemotherapeutic responses were analyzed and immunological features (immunomodulators, immune checkpoint molecules, cancer immunity cycle, and tumor-infiltrating immune cells) were systematically evaluated across gastric cancer. Weighted gene co-expression network (WGCNA) was conducted for screening aging molecular phenotype-relevant genes, and key genes were identified with Molecular Complex Detection (MCODE) analyses. Expressions of key genes were examined in 20 paired tumors and controls with RT-qPCR and Western blotting. Proliferation and apoptosis were investigated in two gastric cancer cells under MYL9 deficiency. Three aging-based molecular phenotypes (namely, C1, C2, and C3) were conducted in gastric cancer. Phenotype C1 presented the most prominent survival advantage and highest mutational frequencies. Phenotype C2 indicated low responses to sorafenib and gefitinib, while C3 indicated low responses to vinorelbine and gemcitabine. Additionally, phenotype C2 was characterized by enhanced immune and stromal activation and an inflamed tumor microenvironment. Seven aging molecular phenotype-relevant key genes (ACTA2, CALD1, LMOD1, MYH11, MYL9, MYLK, and TAGLN) were identified, which were specifically upregulated in tumors and in relation to dismal prognosis. Among them, MYL9 deficiency reduced proliferation and enhanced apoptosis in gastric cancer cells. Collectively, aging-based molecular subtypes may offer more individualized therapy recommendations and prognosis assessment for patients in distinct subtypes. Show less

To enable hearing, the sensory hair cell contains specialized subcellular structures at its apical region, including the actin-rich cuticular plate and circumferential band. ACF7 (actin crosslinking family protein 7), encoded by the gene Show less

In this study, we integrated large-scale GWAS summary data and used the predicted transcriptome-wide association study method to discover novel genes associated with osteoporosis. We identified 204 candidate genes, which provide novel clues for understanding the genetic mechanism of osteoporosis and indicate potential therapeutic targets. Osteoporosis is a highly polygenetic disease characterized by low bone mass and deterioration of the bone microarchitecture. Our objective was to discover novel candidate genes associated with osteoporosis. To identify potential causal genes of the associated loci, we investigated trait-gene expression associations using the transcriptome-wide association study (TWAS) method. This method directly imputes gene expression effects from genome-wide association study (GWAS) data using a statistical prediction model trained on GTEx reference transcriptome data. We then performed a colocalization analysis to evaluate the posterior probability of biological patterns: associations characterized by a single causal variant or multiple distinct causal variants. Finally, a functional enrichment analysis of gene sets was performed using the VarElect and CluePedia tools, which assess the causal relationships between genes and a disease and search for potential gene's functional pathways. The osteoporosis-associated genes were further confirmed based on the differentially expressed genes profiled from mRNA expression data of bone tissue. Our analysis identified 204 candidate genes, including 154 genes that have been previously associated with osteoporosis, 50 genes that have not been previously discovered. A biological function analysis found that 20 of the candidate genes were directly associated with osteoporosis. Further analysis of multiple gene expression profiles showed that 15 genes were differentially expressed in patients with osteoporosis. Among these, SLC11A2, MAP2K5, NFATC4, and HSP90B1 were enriched in four pathways, namely, mineral absorption pathway, MAPK signaling pathway, Wnt signaling pathway, and PI3K-Akt signaling pathway, which indicates a causal relationship with the occurrence of osteoporosis. We demonstrated that transcriptome fine-mapping identifies more osteoporosis-related genes and provides key insight into the development of novel targeted therapeutics for the treatment of osteoporosis. Show less

In the past several decades obesity has become one of the greatest health burdens worldwide. Diet high in fats and fructose is one of the main causes for the prevalence of metabolic disorders including obesity. Promoting brown or beige adipocyte development and activity is regarded as a potential treatment of obesity. Mondo family transcription factors including MondoA and carbohydrate response element binding protein (ChREBP) are critical for nutrient-sensing in multiple metabolic organs including the skeletal muscle, liver, adipose tissue and pancreas. Under normal nutrient conditions, MondoA and ChREBP contribute to maintaining metabolic homeostasis. When nutrient is overloaded, Mondo family transcription factors directly regulate glucose and lipid metabolism in brown and beige adipocytes or modulate the crosstalk between metabolic organs. In this review, we aim to provide an overview of recent advances in the understanding of MondoA and ChREBP in sensing nutrients and regulating obesity or related pathological conditions. Show less

Hepatocellular carcinoma (HCC) is a globally prevailing cancer with a low 5-year survival rate. Little is known about its intricate gene expression profile. Single-cell RNA sequencing is an indispensable tool to explore the genetic characteristics of HCC at a more detailed level. In this study, we profiled the gene expression of single cells from human HCC tumor and para-tumor tissues using the Smart-seq 2 sequencing method. Based on differentially expressed genes, we identified heterogeneous subclones in HCC tissues, including five HCC and two hepatocyte subclones. We then carried out hub-gene co-network and functional annotations analysis followed pseudo-time analysis with regulated transcriptional factor co-networks to determine HCC cellular trajectory. We found that MLX interacting protein like (MLXIPL) was commonly upregulated in the single cells and tissues and associated with a poor survival rate in HCC. Mechanistically, MLXIPL activation is crucial for promoting cell proliferation and inhibits cell apoptosis by accelerating cell glycolysis. Taken together, our work identifies the heterogeneity of HCC subclones, and suggests MLXIPL might be a promising therapeutic target for HCC. Show less

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant heart disease. An induced pluripotent stem cell line (EHTJUi003-A) was generated from umbilical cord blood mononuclear cells (UCBMCs) of a female neonate with heterozygous mutation of p.L460Wfs (c.1377delC) in the MYBPC3 gene. This iPSC model offers a very valuable resource to study the pathological mechanism of HCM in vitro. Show less

The mutation MYBPC3-E334K is a culprit mutation of hypertrophic cardiomyopathy (HCM). The pathogenicity of MYBPC3-E334K is conflicting in ClinVar because of the limited segregation data and the relatively high frequency in gnomAD (0.03% overall, with 0.3% in East Asians and 0.8% in Japanese). The main aim is to clarify the clinical importance and phenotype-genotype correlations in subjects with or without MYBPC3-E334K alone. The prevalence of MYBPC3-E334K was sequenced in 1017 HCM unrelated probands. The clinical features, morphology phenotypes, and electrical phenotypes were further analyzed according to the phenotype and genotype status in families with single-mutation MYBPC3-E334K. Nine of 1017 (0.88%) unrelated HCM probands were detected harboring MYBPC3-E334K, and three of them harbored a second variant in sarcomere protein gene. Family study and co-segregation analyses indicated that patients with single-mutation MYBPC3-E334K showed autosomal dominant mode of inheritance with incomplete penetrance. The overall disease penetrance was 52.6%, and the disease penetrance was higher in males than in females (100% in men vs 25% in women, p = 0.003). The mean age at diagnosis of males was approximately 25 years younger than females (36.57 ± 18.65 vs 62.33 ± 12.10, p = 0.062). The variant MYBPC3-E334K was classified as a likely pathogenic variant, and a second sarcomere variant did not reveal obvious cumulative effects. The patients harboring single-mutation MYBPC3-E334K had incomplete penetrance, and males demonstrated higher penetrance and early onset HCM than females. A second sarcomere variant did not reveal obvious cumulative effects. Show less

Liver X receptor α (LXRα; NR1H3) is an important transcription factor that can facilitate milk fat synthesis by regulating the transcription of FASN in mice and goats. Nevertheless, the lipid synthesis related to LXRα and its regulation on FASN in the buffalo mammary gland remain elusive. Here, we demonstrated that the mRNA and protein expression of LXRα in buffalo mammary tissue increased in lactation compared with that in the dry-off period. Overexpression of NR1H3 enhanced the lipid droplet formation and triacylglycerol concentration in buffalo mammary epithelial cells (BuMEC), whereas the knockdown of NR1H3 resulted in a decrease in the number of lipid droplets. At the same time, NR1H3 also affected the expression of regulatory factors (INSIG1, INSIG2, SREBF1, and PPARG) related to milk fat synthesis and that of genes involved in de novo synthesis (FASN, ACACA, and SCD), and uptake and transport (LPL, CD36, and FABP3) of fatty acids as well as triacylglycerol synthesis (GPAM, APGAT6, and DGAT1). Luciferase reporter assays indicated that overexpression of NR1H3 resulted in an increase in the activity of FASN promoter, whereas the knockdown of NR1H3 had an opposite effect. When NR1H3 was overexpressed, mutations in LXRE or SRE could decrease the promoter activity of FASN. Furthermore, mutagenesis of both LXRE and SRE within the FASN promoter completely eliminated the induced activity of LXRα. Our results reveal that buffalo LXRα promotes milk fat synthesis through regulating the expression of FASN by directly interacting with FASN promoter and affecting the SREBF1 expression. This study underscores a crucial role of LXRα in regulating lipid synthesis of the buffalo mammary gland. Show less

SCAP (SREBF chaperone) regulates SREBFs (sterol regulatory element binding transcription factors) processing and stability, and, thus, becomes an emerging drug target to treat dyslipidemia and fatty liver disease. However, the current known SCAP inhibitors, such as oxysterols, induce endoplasmic reticulum (ER) stress and NR1H3/LXRα (nuclear receptor subfamily 1 group H member 3)-SREBF1/SREBP-1 c-mediated hepatic steatosis, which severely limited the clinical application of this inhibitor. In this study, we identified a small molecule, lycorine, which binds to SCAP, which suppressed the SREBF pathway without inducing ER stress or activating NR1H3. Mechanistically, lycorine promotes SCAP lysosomal degradation in a macroautophagy/autophagy-independent pathway, a mechanism completely distinct from current SCAP inhibitors. Furthermore, we determined that SQSTM1 captured SCAP after its exit from the ER. The interaction of SCAP and SQSTM1 requires the WD40 domain of SCAP and the TB domain of SQSTM1. Interestingly, lycorine triggers the lysosome translocation of SCAP independent of autophagy. We termed this novel protein degradation pathway as the SQSTM1-mediated autophagy-independent lysosomal degradation (SMAILD) pathway. Show less

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease worldwide. Autophagy was reported to be related to the pathogenesis of DN. This research investigated the function of the Nucleoporin 160 (Nup160) gene in regulating autophagy in DN. A mouse model of DN was established through an intraperitoneal injection of streptozotocin (STZ). Normal rat kidney tubular epithelial cells (NRK-52E) were treated with high glucose to induce DN in vitro. Real-time quantitative polymerase chain reaction (RT-qPCR), western blot, immunofluorescence assays were conducted to measure the expression of NUP160, autophagy-associated proteins, and inflammatory cytokines in vitro and in vivo. Pathological changes of kidney and liver tissues were analyzed using hematoxylin and eosin (H&E), Masson and periodic acid-silver (PAS) staining. The body weight, blood glucose, renal and lipid profiles of DN mice were examined. In this study, DN mice showed serious pathological injury. NUP160 expression was upregulated, autophagy was inhibited, and inflammatory response was increased in DN mice. Depletion of NUP160 restored autophagy and inhibited inflammation and fibrosis in high glucose (HG)-treated NRK-52E cells and STZ-induced DN mice by downregulating the expression of p62 and Collagen IV (Col-Ⅳ), increasing the ratio of LC3II/LC3I, and inactivating nuclear factor (NF)-κB signaling. Moreover, NUP160 knockdown could ameliorate pathological damage and glucose tolerance in DN mice. Overall, this study is the first to demonstrate the key role of NUP160 silencing in promoting autophagy against diabetic injury in DN. Show less

Vacuolating cytotoxin (VacA) is an important virulence factor of Helicobacter pylori (H. pylori). It was previously believed that VacA can trigger the cascade of apoptosis on mitochondria to lead to cell apoptosis. Recently, it was found that VacA can induce autophagy. However, the molecular mechanism by which VacA induces autophagy is largely unknown. We aimed to explore the molecular mechanism of autophagy induced by H. pylori in gastric cancer cells and the effect of autophagy on the survival of gastric cancer cells. The autophagy of human gastric cancer cell line SGC7901 was detected by Western blot and RT-PCR in the treatment of VacA protein of H. pylori. The relationship between autophagy and reactive oxygen species (ROS) in the proliferation of gastric cancer cells were studied by gene expression silences (siRNA) and CM-H2DCFDA (DCF) staining. The results showed that VacA protein secreted by H. pylori in the supernatant stimulated autophagy in SGC7901 cells. After VacA protein treatment, the mRNA expressions of BECN1, ATG7 and PIK3C3, were up-regulated. ATG7 silencing by siRNA inhibited VacA-induced autophagy. Furthermore, our data demonstrated that VacA protein increased ROS levels. Addition of the antioxidant N-acetyl-L-cysteine (NAC) suppressed the levels of ROS, leading to inhibition of autophagy. H. pylori VacA is a key toxin that induces autophagy by increased ROS levels. And our findings demonstrated that VacA significantly inhibited proliferation in SGC7901 cells. Show less

Severe negative energy balance around parturition is an important contributor to ketosis, a metabolic disorder that occurs most frequently in the peripartal period. Autophagy and mitophagy are important processes responsible for breaking down useless or toxic cellular material, and in particular damaged mitochondria. However, the role of autophagy and mitophagy during the occurrence and development of ketosis is unclear. The objective of this study was to investigate autophagy and mitophagy in the livers of cows with subclinical ketosis (SCK) and clinical ketosis (CK). We assessed autophagy by measuring the protein abundance of microtubule-associated protein 1 light chain 3-II (LC3-II; encoded by MAP1LC3) and sequestosome-1 (p62, encoded by SQSTM1), as well as the mRNA abundance of autophagy-related genes 5 (ATG5), 7 (ATG7), and 12 (ATG12), beclin1 (BECN1), and phosphatidylinositol 3-kinase catalytic subunit type 3 (PIK3C3). Mitophagy was evaluated by measuring the protein abundance of the mitophagy upstream regulators PTEN-induced putative kinase 1 (PINK1) and Parkin. Liver and blood samples were collected from healthy cows [n = 15; blood β-hydroxybutyrate (BHB) concentration <1.2 mM], cows with SCK (n = 15; blood BHB concentration 1.2 to 3.0 mM) and cows with CK (n = 15; blood BHB concentration >3.0 mM with clinical signs) with similar lactation numbers (median = 3, range = 2 to 4) and days in milk (median = 6, range = 3 to 9). The serum activity of aspartate aminotransferase and alanine aminotransferase was greater in cows with CK than in healthy cows. Levels of oxidative stress biomarkers malondialdehyde and hydrogen peroxide were also higher in liver tissue from ketotic cows (SCK and CK) than from healthy cows. Compared with cows with CK and healthy cows, the hepatic mRNA abundance of MAP1LC3, SQSTM1, ATG5, ATG7, ATG12, and PIK3C3 was upregulated in cows with SCK. Compared with healthy cows, cows with SCK had a lower abundance of p62 and a greater abundance of LC3-II, but levels of both were higher in cows with CK. The mRNA abundance of ATG12 was lower in cows with CK than in healthy cows. Furthermore, the hepatic protein abundance of PINK1 and Parkin was greater in cows with SCK and slightly lower in cows with CK than in healthy cows. These data demonstrated differences in the hepatic activities of autophagy and mitophagy in cows with SCK compared with cows with CK. Although the precise mechanisms for these differences could not be discerned, autophagy and mitophagy seem to be involved in ketosis. Show less

Although molecular targeted therapies have recently displayed therapeutic effects in acute myeloid leukemia (AML), limited response and acquired resistance remain common problems. Numerous studies have associated autophagy, an essential degradation process involved in the cellular response to stress, with the development and therapeutic response of cancers including AML. Thus, we review studies on the role of autophagy in AML development and summarize the linkage between autophagy and several recurrent genetic abnormalities in AML, highlighting the potential of capitalizing on autophagy modulation in targeted therapy for AML. Show less

To investigate the mechanism of vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) in Müller cell (MC) viability and neuroprotection in diabetic retinopathy (DR), we examined the role of VEGF in MC viability and BDNF production, and the effect of BDNF on MC viability under diabetic conditions. Mouse primary MCs and cells of a rat MC line, rMC1, were used in investigating MC viability and BDNF production under diabetic conditions. VEGF-stimulated BDNF production was confirmed in mice. The mechanism of BDNF-mediated MC viability was examined using siRNA knockdown. Under diabetic conditions, recombinant VEGF (rVEGF) stimulated MC viability and BDNF production in a dose-dependent manner. rBDNF also supported MC viability in a dose-dependent manner. Targeting BDNF receptor tropomyosin receptor kinase B (TRK-B) with siRNA knockdown substantially downregulated the activated (phosphorylated) form of serine/threonine-specific protein kinase (AKT) and extracellular signal-regulated kinase (ERK), classical survival and proliferation mediators. Finally, the loss of MC viability in Show less