Esophageal cancer is one of the most common cancers worldwide with poor prognosis and high mortality. The transcription factor Expression of Cumulatively, these results establish an important mechanis Show more
Esophageal cancer is one of the most common cancers worldwide with poor prognosis and high mortality. The transcription factor Expression of Cumulatively, these results establish an important mechanism by which decrease in miR-203 expression potentiates metastatic progression in EC via USP26-mediated stabilization of Snail1. Hence, miR-203 can serve as a biomarker of metastasis in EC and is a potential target for therapeutic intervention in EC. Show less
Macroautophagy/autophagy plays key roles in development, oncogenesis, and cardiovascular and metabolic diseases. Autophagy-specific class III phosphatidylinositol 3-kinase complex I (PtdIns3K-C1) is e Show more
Macroautophagy/autophagy plays key roles in development, oncogenesis, and cardiovascular and metabolic diseases. Autophagy-specific class III phosphatidylinositol 3-kinase complex I (PtdIns3K-C1) is essential for autophagosome formation. However, the regulation of this complex formation requires further investigation. Here, we discovered that STYK1 (serine/threonine/tyrosine kinase 1), a member of the receptor tyrosine kinases (RTKs) family, is a new upstream regulator of autophagy. We discovered that STYK1 facilitated autophagosome formation in human cells and zebrafish, which was characterized by elevated LC3-II and lowered SQSTM1/p62 levels and increased puncta formation by several marker proteins, such as ATG14, WIPI1, and ZFYVE1. Moreover, we observed that STYK1 directly binds to the PtdIns3K-C1 complex as a homodimer. The binding with this complex was promoted by Tyr191 phosphorylation, by means of which the kinase activity of STYK1 was elevated. We also demonstrated that STYK1 elevated the serine phosphorylation of BECN1, thereby decreasing the interaction between BECN1 and BCL2. Furthermore, we found that STYK1 preferentially facilitated the assembly of the PtdIns3K-C1 complex and was required for PtdIns3K-C1 complex kinase activity. Taken together, our findings provide new insights into autophagy induction and reveal evidence of novel crosstalk between the components of RTK signaling and autophagy. Show less
Bombesin-like receptor 3 (BRS3) is an orphan receptor and Brs3 knockout mice develop obesity with increased food intake and reduced resting metabolic rate and body temperature. The neuronal population Show more
Bombesin-like receptor 3 (BRS3) is an orphan receptor and Brs3 knockout mice develop obesity with increased food intake and reduced resting metabolic rate and body temperature. The neuronal populations contributing to these effects were examined. We studied energy metabolism in mice with Cre-mediated recombination causing 1) loss of BRS3 selectively in SIM1- or MC4R-expressing neurons or 2) selective re-expression of BRS3 from a null background in these neurons. The deletion of BRS3 in MC4R neurons increased body weight/adiposity, metabolic efficiency, and food intake, and reduced insulin sensitivity. BRS3 re-expression in these neurons caused partial or no reversal of these traits. However, these observations were confounded by an obesity phenotype caused by the Mc4r-Cre allele, independent of its recombinase activity. The deletion of BRS3 in SIM1 neurons increased body weight/adiposity and food intake, but not to the levels of the global null. The re-expression of BRS3 in SIM1 neurons reduced body weight/adiposity and food intake, but not to wild type levels. The deletion of BRS3 in either MC4R- or SIM1-expressing neurons affected body temperature, with re-expression in either population reversing the null phenotype. MK-5046, a BRS3 agonist, increases light phase body temperature in wild type, but not Brs3 null, mice and BRS3 re-expression in either population restored response to MK-5046. BRS3 in both MC4R- and SIM1-expressing neurons contributes to regulation of body weight/adiposity, insulin sensitivity, food intake, and body temperature. Show less
Growth differentiation factor 15 (GDF15), a member of the transforming growth factor β (TGF-β) superfamily, is a prognostic biomarker of cervical cancer. In addition, GDF15 has been reported to enhanc Show more
Growth differentiation factor 15 (GDF15), a member of the transforming growth factor β (TGF-β) superfamily, is a prognostic biomarker of cervical cancer. In addition, GDF15 has been reported to enhance the migration of colorectal cancer cells and liver cancer stem-like cells. However, the mechanism by which GDF15 promotes cervical cancer cell migration is not completely understood. Here, we report that GDF15 expression is enhanced in cervical cancer tissues, as well as in cultured cervical cancer cells. ShGDF15 transfection markedly inhibited expression of Vimentin, N-cadherin and Snail1, and resulted in up-regulation of E-cadherin expression in HT-3 and HeLa cells. Moreover, knockdown of GDF15 suppressed wound healing rate and reduced the number of invasive cells. Furthermore, knockdown of GDF15 significantly suppressed the expression of phosphorylated Smad2 and Smad3. The addition of TGF-β1 partially abolished the inhibitory effects of GDF15 knockdown on the migration and invasion of cervical cancer cells. In summary, we report here that GDF15 knockdown inhibits migration and invasion of cervical cancer cells in vitro through the TGF-β/Smad2/3/Snail1 pathway. Show less
Biochanin A (BCA), a dietary isoflavone extracted from red clover and cabbage, has been shown to antagonize hypertension and myocardial ischemia/reperfusion injury. However, very little is known about Show more
Biochanin A (BCA), a dietary isoflavone extracted from red clover and cabbage, has been shown to antagonize hypertension and myocardial ischemia/reperfusion injury. However, very little is known about its role in atherogenesis. The aim of this study was to observe the effects of BCA on atherosclerosis and explore the underlying mechanisms. Our results showed that administration of BCA promoted reverse cholesterol transport (RCT), improved plasma lipid profile, and decreased serum proinflammatory cytokine levels and atherosclerotic lesion area in apoE Show less
Esophageal squamous cell carcinoma (ESCC) is the main subtype of esophageal cancer in China, and the prognosis of patients remains poor mainly due to the occurrence of lymph node and distant metastasi Show more
Esophageal squamous cell carcinoma (ESCC) is the main subtype of esophageal cancer in China, and the prognosis of patients remains poor mainly due to the occurrence of lymph node and distant metastasis. The long non‑coding RNA (lncRNA) maternally expressed gene 3 (MEG3) has been shown to have tumor‑suppressive properties and to play an important role in epithelial‑to‑mesenchymal transition (EMT) in some solid tumors. However, whether MEG3 is involved in EMT in ESCC remains unclear. In the present study, the MEG3 expression level and its association with tumorigenesis were determined in 43 tumor tissues of patients with ESCC and in ESCC cells using reverse transcription‑quantitative PCR analysis. Gene microarray analysis was performed to detect differentially expressed genes (DEGs). Based on the functional annotation results, the effects of ectopic expression of MEG3 on cell growth, migration, invasion and EMT were assessed. MEG3 expression level was found to be markedly lower in tumor tissues and cells. Statistical analysis revealed that MEG3 expression was significantly negatively associated with lymph node metastasis and TNM stage in ESCC. Fluorescence in situ hybridization assay demonstrated that MEG3 was expressed mainly in the nucleus. Ectopic expression of MEG3 inhibited cell proliferation, migration, invasion and cell cycle progression in EC109 cells. Gene microarray results demonstrated that 177 genes were differentially expressed ≥2.0 fold in MEG3‑overexpressing cells, including 23 upregulated and 154 downregulated genes. Functional annotation revealed that the DEGs were mainly involved in amino acid biosynthetic process, mitogen‑activated protein kinase signaling, and serine and glycine metabolism. Further experiments indicated that the ectopic expression of MEG3 significantly suppressed cell proliferation, migration, invasion and EMT by downregulating phosphoserine aminotransferase 1 (PSAT1). In pathological tissues, PSAT1 and MEG3 were significantly negatively correlated, and high expression of PSAT1 predicted poor survival. Taken together, these results suggest that MEG3 may be a useful prognostic biomarker and may suppress EMT by inhibiting the PSAT1‑dependent glycogen synthase kinase‑3β/Snail signaling pathway in ESCC. Show less
Telmisartan (TLM), a highly selective angiotensin II type 1 receptor blocker (ARB) and partial PPAR-γ agonist, has versatile beneficial effects against oxidative stress, apoptosis, inflammatory respon Show more
Telmisartan (TLM), a highly selective angiotensin II type 1 receptor blocker (ARB) and partial PPAR-γ agonist, has versatile beneficial effects against oxidative stress, apoptosis, inflammatory responses and epithelial-mesenchymal transition (EMT). However, its underlying mechanism of inhibiting oxalate and calcium oxalate (CaOx) crystal-induced EMT by activating the PPAR-γ pathway remains unclear. CCK-8 assays were used to evaluate the effects of TLM on cell viability. In addition, intracellular reactive oxygen species (ROS) levels were measured by the cell-permeable fluorogenic probe 2,7-dichlorofluorescein diacetate (DCFH-DA). Wound-healing and Transwell assays were used to evaluate the migration ability of HK2 cells exposed to oxalate. Moreover, immunofluorescence, immunohistochemistry and western blotting were used to examine the expression of E-cadherin, N-cadherin, vimentin and α-SMA and explore the underlying molecular mechanisms in HK2 cells and a stone-forming rat model. Our results showed that TLM treatment could protect HK2 cells from oxalate-induced cytotoxicity and oxidative stress injury. Additionally, TLM prevented EMT induction by oxalate and CaOx crystals via the PPAR-γ-AKT/STAT3/p38 MAPK-Snail pathway in vitro and in vivo. However, knockdown of PPAR-γ with small interfering RNA or the PPAR-γ-specific antagonist GW9662 abrogated these protective effects of TLM. As a PPAR-γ agonist, TLM can ameliorate oxalate and CaOx crystal-induced EMT by exerting an antioxidant effect through the PPAR-γ-AKT/STAT3/p38 MAPK-Snail signaling pathway. Therefore, TLM can block EMT progression and could be a potential therapeutic agent for preventing and treating calcium oxalate urolithiasis formation and recurrence. Show less
Cip1, a newly identified yeast analog of p21, is a Cln3-CDK inhibitor that negatively regulates cell-cycle START. However, its function remains poorly understood. In this study, we found that deletion Show more
Cip1, a newly identified yeast analog of p21, is a Cln3-CDK inhibitor that negatively regulates cell-cycle START. However, its function remains poorly understood. In this study, we found that deletion of Show less
Melanocortin-4 receptor (MC4R) plays important roles in regulation of multiple physiological processes, and interaction of MC4R and melanocortin receptor accessory protein 2 (MRAP2) is suggested to pl Show more
Melanocortin-4 receptor (MC4R) plays important roles in regulation of multiple physiological processes, and interaction of MC4R and melanocortin receptor accessory protein 2 (MRAP2) is suggested to play pivotal role in energy balance of vertebrates. Topmouth culter ( Show less
Scabies is a neglected tropical disease of global significance. Our understanding of host-parasite interactions has been limited, particularly in crusted scabies (CS), a severe clinical manifestation Show more
Scabies is a neglected tropical disease of global significance. Our understanding of host-parasite interactions has been limited, particularly in crusted scabies (CS), a severe clinical manifestation involving hyper-infestation of Sarcoptes scabiei mites. Susceptibility to CS may be associated with immunosuppressive conditions but CS has also been seen in cases with no identifiable risk factor or immune deficit. Due to ethical and logistical difficulties with undertaking research on clinical patients with CS, we adopted a porcine model which parallels human clinical manifestations. Transcriptomic analysis using microarrays was used to explore scabies pathogenesis, and to identify early events differentiating pigs with ordinary (OS) and crusted scabies. Pigs with OS (n = 4), CS (n = 4) and non-infested controls (n = 4) were compared at pre-infestation, weeks 1, 2, 4 and 8 post-infestation. In CS relative to OS, there were numerous differentially expressed genes including pro-inflammatory cytokines (IL17A, IL8, IL19, IL20 and OSM) and chemokines involved in immune cell activation and recruitment (CCL20, CCL27 and CXCL6). The influence of genes associated with immune regulation (CD274/PD-L1 and IL27), immune signalling (TLR2, TLR8) and antigen presentation (RFX5, HLA-5 and HLA-DOB) were highlighted in the early host response to CS. We observed similarities with gene expression profiles associated with psoriasis and atopic dermatitis and confirmed previous observations of Th2/17 pronounced responses in CS. This is the first comprehensive study describing transcriptional changes associated with the development of CS and significantly, the distinction between OS and CS. This provides a basis for clinical follow-up studies, potentially identifying new control strategies for this severely debilitating disease. Show less
Contraction stimulates skeletal muscle glucose uptake predominantly through activation of AMP-activated protein kinase (AMPK) and Rac1. However, the molecular details of how contraction activates thes Show more
Contraction stimulates skeletal muscle glucose uptake predominantly through activation of AMP-activated protein kinase (AMPK) and Rac1. However, the molecular details of how contraction activates these signaling proteins are not clear. Recently, Axin1 has been shown to form a complex with AMPK and liver kinase B1 during glucose starvation-dependent activation of AMPK. Here, we demonstrate that electrical pulse-stimulated (EPS) contraction of C2C12 myotubes or treadmill exercise of C57BL/6 mice enhanced reciprocal coimmunoprecipitation of Axin1 and AMPK from myotube lysates or gastrocnemius muscle tissue. Interestingly, EPS or exercise upregulated total cellular Axin1 levels in an AMPK-dependent manner in C2C12 myotubes and gastrocnemius mouse muscle, respectively. Also, direct activation of AMPK with 5-aminoimidazole-4-carboxamide ribonucleotide treatment of C2C12 myotubes or gastrocnemius muscle elevated Axin1 protein levels. On the other hand, siRNA-mediated Axin1 knockdown lessened activation of AMPK in contracted myotubes. Further, AMPK inhibition with compound C or siRNA-mediated knockdown of AMPK or Axin1 blocked contraction-induced GTP loading of Rac1, p21-activated kinase phosphorylation, and contraction-stimulated glucose uptake. In summary, our results suggest that an AMPK/Axin1-Rac1 signaling pathway mediates contraction-stimulated skeletal muscle glucose uptake. Show less
Macrophages differentiated into a classically activated (M1) or alternatively activated phenotype (M2) in infection and tumor, but the precise effects of glycolysis and oxidative phosphorylation (OXPH Show more
Macrophages differentiated into a classically activated (M1) or alternatively activated phenotype (M2) in infection and tumor, but the precise effects of glycolysis and oxidative phosphorylation (OXPHOS) metabolic pathway remain unclear. Herein, the effects of glycolysis or OXPHOS on macrophage polarizations were investigated using a pharmacological approach in mice. 2-Deoxy-D-glucose (2-DG) treatments, which blocks the key enzyme hexokinase of glycolysis, efficiently inhibits a specific switch to M1 lineage, decreasing the secretion of pro-inflammatory cytokines and expressions of co-stimulatory molecules associated with relieving infectious inflammation Show less
DUSP6 functions as an important negative feedback component of the MAPK/ERK signaling pathway. Although DUSP6 expression is tightly regulated by ERK1/2 signaling, the molecular mechanism of this regul Show more
DUSP6 functions as an important negative feedback component of the MAPK/ERK signaling pathway. Although DUSP6 expression is tightly regulated by ERK1/2 signaling, the molecular mechanism of this regulation remains partially understood. In this work, we show that the transcriptional repressor CIC functions downstream of the ERK1/2 signaling to negatively regulate DUSP6 expression. CIC directly represses DUSP6 transcription by binding to three Show less
Recent studies have demonstrated that commercially available lipid-lowering drugs cause various side effects; therefore, searching for anti-hyperlipidaemic compounds with lower toxicity is a research Show more
Recent studies have demonstrated that commercially available lipid-lowering drugs cause various side effects; therefore, searching for anti-hyperlipidaemic compounds with lower toxicity is a research hotspot. This study was designed to investigate whether the marine-derived compound, 5-hydroxy-3-methoxy-5-methyl-4-butylfuran-2(5H)-one, has an anti-hyperlipidaemic activity, and the potential underlying mechanism in vitro. Results showed that the furanone had weaker cytotoxicity compared to positive control drugs. In RAW 264.7 cells, the furanone significantly lowered ox-LDL-induced lipid accumulation (~50%), and its triglyceride (TG)-lowering effect was greater than that of liver X receptor (LXR) agonist T0901317. In addition, it significantly elevated the protein levels of peroxisome proliferator-activated receptors (PPARα) and ATP-binding cassette (ABC) transporters, which could be partially inhibited by LXR antagonists, GSK2033 and SR9243. In HepG2 cells, it significantly decreased oleic acid-induced lipid accumulation, enhanced the protein levels of low-density lipoprotein receptor (LDLR), ABCG5, ABCG8 and PPARα, and reduced the expression of sterol regulatory element-binding protein 2 (~32%). PPARα antagonists, GW6471 and MK886, could significantly inhibit the furanone-induced lipid-lowering effect. Furthermore, the furanone showed a significantly lower activity on the activation of the expression of lipogenic genes compared to T0901317. Taken together, the furanone exhibited a weak cytotoxicity but had powerful TC- and TG-lowering effects most likely through targeting LXRα and PPARα, respectively. These findings indicate that the furanone has a potential application for the treatment of dyslipidaemia. Show less
The Jianchang duck is mainly distributed in Southwest China, and has the characteristics of fast growth rate and strong abilities in lipid deposition in the liver. In order to investigate the effects Show more
The Jianchang duck is mainly distributed in Southwest China, and has the characteristics of fast growth rate and strong abilities in lipid deposition in the liver. In order to investigate the effects of domestication process on formation of the unique characteristics of Jianchang duck, the whole genome of sixteen individuals and three pooling of Jianchang duck were re-sequenced, and genome data of 70 mallards and 83 domestic ducks from thirteen different places in China were obtained from NCBI. The population stratification and evolution analysis showed gene exchanges existed between the Jianchang and other domestic duck populations, as well as Jianchang ducks and mallards. Genomic comparison between mallards and Jianchang ducks showed genes, including Show less
The existence of cancer stem cells (CSCs) accounts for hepatocellular carcinoma (HCC) treatment resistance, relapse, and metastasis. Although the elimination of cancer stem cells is crucial for cancer Show more
The existence of cancer stem cells (CSCs) accounts for hepatocellular carcinoma (HCC) treatment resistance, relapse, and metastasis. Although the elimination of cancer stem cells is crucial for cancer treatment, strategies for their elimination are limited. Here, we report that a remarkable increase in PIK3C3 was detected in HCC tissues and liver CSCs. Upregulated PIK3C3 facilitated liver CSC expansion in HCC cells; RNA interference-mediated silencing of PIK3C3 had an opposite effect. Furthermore, PIK3C3 inhibition by inhibitors effectively eliminated liver CSCs and inhibited the growth of tumors in vivo. The phosphoinositide 3-kinase (PI3K) pathway is considered an important hallmark of cancer. One of our recent studies found that prolonged inhibition by inhibitors of class I PI3K induces liver CSCs expansion. To our surprise, PIK3C3 inhibition blocked the expansion of CSCs induced by PI3K inhibitor; moreover, treatment with the combination of PIK3C3 inhibitor and PI3K inhibitor in maximal suppresses the expansion of liver CSCs of tumors in mice. Mechanistically, inhibition of PIK3C3 inhibit the activation of SGK3, a CSCs promoter, induced by PI3K inhibitor. We also show that PIK3C3 inhibitor suppresses liver CSCs by activation of the AMP-activated kinase (AMPK). Although PIK3C3 plays a critical role in autophagy, we find that PIK3C3 regulates liver CSCs independent of the autophagy process. These findings uncover the effective suppression of liver CSCs by targeting PIK3C3, and targeting PIK3C3 in combination with PI3K inhibitor inhibits the expansion of liver CSCs efficiently, which is an attractive therapeutic regimen for the treatment of HCC. Show less
Invasive pulmonary aspergillosis is a life-threatening disease, particularly in immunocompromised patients, despite currently available therapy. IL-27 is an important regulatory cytokine in infection Show more
Invasive pulmonary aspergillosis is a life-threatening disease, particularly in immunocompromised patients, despite currently available therapy. IL-27 is an important regulatory cytokine in infection and immunity. However, its role in the pathogenesis of invasive pulmonary aspergillosis remains unknown. Here we found that Show less
Melanocortin-4 receptor (MC4R) was considered as an essential modifiers in feelings intake, the regulation of metabolism and body weight. This study aimed at identifying polymorphisms in MC4R gene tha Show more
Melanocortin-4 receptor (MC4R) was considered as an essential modifiers in feelings intake, the regulation of metabolism and body weight. This study aimed at identifying polymorphisms in MC4R gene that might associate with carcass quality traits in Chinese indigenous beef cattle breed. qPCR analysis showed that the MC4R gene was widely expressed in various tissues, with predominantly expression levels in heart. Three single-nucleotide polymorphisms (SNPs) were identified, including a mutation (g.85A > G) in 5'untranslated regions (UTR) and two mutations (g.927C > T and g.1069C > G) in exon 1. Based on the χ Show less
Nuclear pore complexes (NPCs), which comprise multiple copies of nucleoporins (Nups), are large protein assemblies embedded in the nuclear envelope connecting the nucleus and cytoplasm. Although it ha Show more
Nuclear pore complexes (NPCs), which comprise multiple copies of nucleoporins (Nups), are large protein assemblies embedded in the nuclear envelope connecting the nucleus and cytoplasm. Although it has been known that Nups affect flowering in Show less
E3 ubiquitin ligase gene, WWP2, is associated with acute kidney injury (AKI). This research was conducted to explore the role of WWP2 in AKI. AKI cell model was produced in human renal proximal tubula Show more
E3 ubiquitin ligase gene, WWP2, is associated with acute kidney injury (AKI). This research was conducted to explore the role of WWP2 in AKI. AKI cell model was produced in human renal proximal tubular epithelial cell line (HK-2) by ischemia-reperfusion (IR) injury. CCK8 and flow cytometry assay were performed to explore the influence of WWP2 overexpression on cell proliferation and apoptosis of IR-induced HK-2 cells. Quantitative real-time PCR and immunoblotting (IB) were performed to assess the gene and protein expression. Then, the influence of WWP2 on p53 ubiquitylation and degradation was estimated by immunoprecipitation assay. Our data indicated that WWP2 was down-regulated and p53 was up-regulated in IR-induced HK-2 cells. WWP2 overexpression promoted proliferation and inhibited apoptosis of IR-induced HK-2 cells. And WWP2 interacted with p53 and regulated p53 ubiquitylation and degradation. Furthermore, the influence of WWP2 on cell proliferation and apoptosis was rescued by MG132 (proteasome inhibitor) treatment. In conclusion, our work described for the first time the role of WWP2 in AKI, showing that WWP2 ameliorated AKI by mediating p53 ubiquitylation and degradation. Moreover, the study offers some important insights into the occurrence of AKI and WWP2 may be a novel target of AKI treatment. SIGNIFICANCE OF THE STUDY: Our data elaborates that WWP2 has protective effect against AKI by mediating p53 ubiquitylation and degradation. Thus, WWP2 might be a therapeutic target for AKI. Show less
A previous study by our group demonstrated a protective role of the neuropeptide secretoneurin (SN) in DL‑isoproterenol hydrochloride (ISO)‑induced cardiac hypertrophy in mice. To further characterize Show more
A previous study by our group demonstrated a protective role of the neuropeptide secretoneurin (SN) in DL‑isoproterenol hydrochloride (ISO)‑induced cardiac hypertrophy in mice. To further characterize the molecular mechanism of SN treatment, an isobaric tags for relative and absolute quantification (iTRAQ)‑based quantitative proteomic analysis was applied to identify putative target proteins and molecular pathways. An SN expression vector was injected into the myocardial tissues of mice, and the animals were then subcutaneously injected with ISO (5 mg/kg/day) for 7 days to induce cardiac hypertrophy. The results of echocardiography and hemodynamic measurements indicated that the function of the heart impaired by ISO treatment was significantly ameliorated via SN gene injection. The investigation of heart proteomics was performed by iTRAQ‑based liquid chromatography‑tandem mass spectrometry analysis. A total of 2,044 quantified proteins and 15 differentially expressed proteins were associated with SN overexpression in mice with cardiac hypertrophy. Functional enrichment analysis demonstrated that these effects were possibly associated with metabolic processes. A protein‑protein interaction network analysis was constructed and the data indicated that apolipoprotein C‑III (Apoc3) was associated with the positive effect of SN on the induction of cardiac hypertrophy in mice. The present study proposed a potential mechanism of SN action on Apoc3 upregulation that may contribute to the amelioration of cardiac hypertrophy. These findings can aid the clinical application of SN in patients with cardiac hypertrophy. Show less
Postsynaptic density protein-93 (PSD-93) plays an important role in ischemic brain injury through N-methyl-D-aspartate receptor (NMDAR)-triggered neurotoxicity. GTPase-activating protein for Ras (SynG Show more
Postsynaptic density protein-93 (PSD-93) plays an important role in ischemic brain injury through N-methyl-D-aspartate receptor (NMDAR)-triggered neurotoxicity. GTPase-activating protein for Ras (SynGAP) is a GAP specifically expressed in the central nervous system to regulate nerve development and synaptic plasticity. However, the link between PSD-93 and SynGAP and their role in ischemic brain injury remain elusive. Here, we showed that PSD-93 interacted with SynGAP and mediated SynGAP ubiquitination and degradation following ischemic brain injury. Proteasome inhibitor MG-132 could reverse the decrease of SynGAP protein level in wild-type mice following cerebral ischemia reperfusion through inhibiting SynGAP ubiquitination. Furthermore, NMDA receptor inhibitor MK801 could increase SynGAP protein level in wild-type mice following cerebral ischemia reperfusion. However, in PSD-93 knockout mice, MG-132 or NMDAR inhibitor had no significant effect on SynGAP expression. Both MG-132 and PSD-93 knockout reduced infarct volume and improved neurological deficit in mice at different time points after cerebral ischemia reperfusion. Furthermore, we identified that 670-685 amino acid sequence of SynGAP was essential to the binding of SynGAP to PSD-93, and designed a fusion peptide Tat-SynGAP (670-685aa) that could attenuate ischemic brain damage in wild-type mice. In conclusion, we provide the first evidence that PSD-93 directly interacts with SynGAP and mediates its ubiquitination and degradation to aggravate ischemic brain damage. Tat-SynGAP (670-685aa) may be considered as a candidate for treatment of acute ischemic stroke. Show less
Dietary L-proline (proline) supplementation during gestation enhances fetal survival and placental development in mice. The objective of the present study was to test the hypothesis that this benefici Show more
Dietary L-proline (proline) supplementation during gestation enhances fetal survival and placental development in mice. The objective of the present study was to test the hypothesis that this beneficial effect of proline was associated with alterations in inflammatory response at the placenta and fetus interface. Populations of immune cells present in peripheral blood mononuclear cells (PBMC) were determined by flow cytometry analysis. The concentrations of immunoglobulins in plasma, and the concentrations of cytokines in plasma, uterus, placenta, and amniotic fluid were measured using a bead-based immunoassay. The data showed that proline supplementation led to higher (P < 0.05) populations of B lymphocytes (CD3 Show less
Hypertriglyceridemia (HTG) is a leading cause of acute pancreatitis. HTG can be caused by either primary (genetic) or secondary etiological factors, and there is increasing appreciation of the interpl Show more
Hypertriglyceridemia (HTG) is a leading cause of acute pancreatitis. HTG can be caused by either primary (genetic) or secondary etiological factors, and there is increasing appreciation of the interplay between the two kinds of factors in causing severe HTG. The main aim of this study was to identify the genetic basis of hypertriglyceridemia-induced acute pancreatitis (HTG-AP) in a Chinese family with three affected members (the proband, his mother and older sister). The entire coding and flanking sequences of LPL, APOC2, APOA5, GPIHBP1 and LMF1 genes were analyzed by Sanger sequencing. The newly identified LPL nonsense variant was subjected to functional analysis by means of transfection into HEK-293 T cells followed by Western blot and activity assays. Previously reported pathogenic LPL nonsense variants were collated and compared with respect to genotype and phenotype relationship. We identified a novel nonsense variant, p.Gln118* (c.351C > T), in the LPL gene, which co-segregated with HTG-AP in the Chinese family. We provided in vitro evidence that this variant resulted in a complete functional loss of the affected LPL allele. We highlighted a role of alcohol abuse in modifying the clinical expression of the disease in the proband. Additionally, our survey of 12 previously reported pathogenic LPL nonsense variants (in 20 carriers) revealed that neither serum triglyceride levels nor occurrence of HTG-AP was distinguishable among the three carrier groups, namely, simple homozygotes, compound heterozygotes and simple heterozygotes. Our findings, taken together, generated new insights into the complex etiology and expression of HTG-AP. Show less
Insults to the axons in the optic nerve head are the primary cause of loss of retinal ganglion cells (RGCs) in traumatic, ischemic nerve injury or degenerative ocular diseases. The central nervous sys Show more
Insults to the axons in the optic nerve head are the primary cause of loss of retinal ganglion cells (RGCs) in traumatic, ischemic nerve injury or degenerative ocular diseases. The central nervous system-specific leucine-rich repeat protein, LINGO-1, negatively regulates axon regeneration and neuronal survival after injury. However, the upstream molecular mechanisms that regulate LINGO-1 signaling and contribute to LINGO-1-mediated death of RGCs are unclear. The expression of SP1 was profiled in optic nerve crush (ONC)-injured RGCs. LINGO-1 level was examined after SP1 overexpression by qRT-PCR. Luciferase assay was used to examine the binding of SP1 to the promoter regions of LINGO-1. Primary RGCs from rat retina were isolated by immunopanning and RGCs apoptosis were determined by Tunnel. SP1 and LINGO-1 expression was investigated using immunohistochemistry and Western bolting. Neuroprotection was assessed by RGC counts, RNFL thickness, and VEP tests after inhibition of SP1 shRNA. We demonstrate that SP1 was upregulated in ONC-injured RGCs. SP1 was bound to the LINGO-1 promoter, which led to increased expression of LINGO-1. Treatment with recombinant Nogo-66 or LINGO-1 promoted apoptosis of RGCs cultured under serum-deprivation conditions, while silencing of SP1 promoted the survival of RGCs. SP1 and LINGO-1 colocalized and were upregulated in ONC-injured retinas. Silencing of SP1 in vivo reduced LINGO-1 expression and protected the structure of RGCs from ONC-induced injury, but there was no sign of recovery in VEP. Our findings imply that SP1 regulates LINGO-1 expression in RGCs in the injured retina and provide insight into mechanisms underlying LINGO-1-mediated RGC death in optic nerve injury. Show less
Metastasis is responsible for 90% of colorectal cancer (CRC)-related deaths. In the present study, we identified a novel key regulator of CRC metastasis, leucine-rich repeats and immunoglobulin-like d Show more
Metastasis is responsible for 90% of colorectal cancer (CRC)-related deaths. In the present study, we identified a novel key regulator of CRC metastasis, leucine-rich repeats and immunoglobulin-like domains protein 3 (LRIG3), which was significantly decreased in CRC tissues and cell lines. Downregulation of LRIG3 was attributed to copy number loss and promoter hypermethylation. Low LRIG3 expression was positively correlated with metastatic clinical features and shorter survival time. Functional experiments showed that knockout of LRIG3 markedly enhanced CRC cell migration and invasion ability, whereas reintroduction of LRIG3 exerted the opposite effects. Regarding the mechanism, LRIG3 could facilitate the binding of DUSP6 to ERK1/2, resulting in the dephosphorylation of ERK1/2 and subsequently downregulation of slug, an epithelial-to-mesenchymal transition trigger, thereby constraining CRC cell motility. Importantly, LRIG3 expression was strongly negatively correlated with slug or p-ERK1/2 expression in CRC tissues. Collectively, our data suggest that LRIG3 is a novel suppressor of CRC metastasis, reactivation of LRIG3 may be a promising therapeutic approach for metastatic CRC patients. Show less
Extracellular signal-regulated kinase 1 and 2 (ERK1/2) have been implicated as important regulators of metabolic homeostasis. Here we generated a new mouse model with genetic deletion of two ERK1/2 ph Show more
Extracellular signal-regulated kinase 1 and 2 (ERK1/2) have been implicated as important regulators of metabolic homeostasis. Here we generated a new mouse model with genetic deletion of two ERK1/2 phosphatases, dual specificity phosphatase (DUSP) 6 and 8, to further define the role of ERK1/2 in obesity development. Dusp6/8 double-null mice demonstrated elevated ERK1/2 phosphorylation in multiple tissues, without any change of phosphorylation of p38 and c-Jun N-terminal kinases (JNKs). Elevated ERK1/2 activity in Dusp6/8 double-null mice was associated with larger hearts and other organs, consistent with greater rate of cell proliferation in these mice. However, ERK1/2 activation was not sufficient to protect the mouse hearts from pathological hypertrophy and interstitial fibrosis following angiotensin II and phenylephrine stimulation. Interestingly, mice lacking DUSP6/8 were resistant to high-fat diet-induced obesity. Serum triglyceride, lipid content in the liver and visceral adipose tissues was also dramatically reduced in Dusp6/8 double-null mice. Furthermore, Dusp6/8 double-null mice had improved glucose tolerance. Mechanistically, we found out that elevated ERK1/2 activity increased the expression levels of genes involved in lipid metabolism and glucose homeostasis. Together, our data suggest that ERK1/2 play an essential role for the management of metabolic homeostasis. Show less
An AP2 family gene CBX1 is involved in mycorrhizal symbiosis and growth of Lotus japonicus. APETALA 2 (AP2) transcriptional regulator is highly conserved in plants. CBX1 from Lotus japonicus is a memb Show more
An AP2 family gene CBX1 is involved in mycorrhizal symbiosis and growth of Lotus japonicus. APETALA 2 (AP2) transcriptional regulator is highly conserved in plants. CBX1 from Lotus japonicus is a member of AP2 family. AMF (Arbuscular mycorrhizal fungi) inoculation experiment demonstrated that expression of CBX1 was significantly induced by AMF. Further promoter analysis showed that the - 764 to - 498 bp region of the CBX1 promoter containing CTTC motif is the AMF responsive region. Functional analysis of cbx1 mutant suggested CBX1 is critical for mycorrhizal symbiosis, especially for arbuscule formation. Moreover, under noncolonized condition, overexpression of CBX1 reduced the root length of L. japonicus but increased the size of root system and shoot length, whereas cbx1 mutant reduced the root size and shoot length, but not effect on root length. In addition, cbx1 altered activity of monolignol biosynthetic gene and increased lignin levels. Collectively, these data indicated that CBX1 is a positive regulator of symbiotic activity and plays roles in the growth of L. japonicus. Show less