Surf4 (Surfeit Locus Protein 4) Deficiency Reduces Intestinal Lipid Absorption and Secretion and Decreases Metabolism in Mice.

BACKGROUND: Postprandial dyslipidemia is a causative risk factor for cardiovascular disease. The majority of absorbed dietary lipids are packaged into chylomicron and then delivered to circulation. Previous studies showed that Surf4 (surfeit locus protein 4) mediates very low-density lipoprotein secretion from hepatocytes. Silencing hepatic Surf4 markedly reduces the development of atherosclerosis in different mouse models of atherosclerosis without causing hepatic steatosis. However, the role of Surf4 in chylomicron secretion is unknown. METHODS: We developed inducible intestinal-specific Surf4 knockdown mice (Surf4IKO) using Vil1Cre-ERT2 and Surf4flox mice. Metabolic cages were used to monitor mouse metabolism. Enzymatic kits were employed to measure serum and tissue lipid levels. The expression of target genes was detected by qRT-PCR and Western Blot. Transmission electron microscopy and radiolabeled oleic acid were used to assess the structure of enterocytes and intestinal lipid absorption and secretion, respectively. Proteomics was performed to determine changes in protein expression in serum and jejunum. RESULTS: Surf4IKO mice, especially male Surf4IKO mice, displayed significant body weight loss, increased mortality, and reduced metabolism. Surf4IKO mice exhibited lipid accumulation in enterocytes and impaired fat absorption and secretion. Lipid droplets and small lipid vacuoles were accumulated in the cytosol and the endoplasmic reticulum lumen of the enterocytes of Surf4IKO mice, respectively. Surf4 colocalized with apoB and co-immunoprecipitated with apoB48 in differentiated Caco-2 cells. Intestinal Surf4 deficiency also significantly reduced serum triglyceride, cholesterol, and free fatty acid levels in mice. Proteomics data revealed that diverse pathways were altered in Surf4IKO mice. In addition, Surf4IKO mice had mild liver damage, decreased liver size and weight, and reduced hepatic triglyceride levels. CONCLUSIONS: Our findings demonstrate that intestinal Surf4 plays an essential role in lipid absorption and chylomicron secretion and suggest that the therapeutic use of Surf4 inhibition requires highly cell/tissue-specific targeting.

ß-secretase 1 overexpression by AAV-mediated gene delivery prevents retina degeneration in a mouse model of age-related macular degeneration.

We reported previously that ß-site amyloid precursor protein cleaving enzyme (BACE1) is strongly expressed in the normal retina and that BACE1-/- mice develop pathological phenotypes associated with age-related macular degeneration (AMD). BACE1 expression is increased within the neural retina and retinal pigment epithelium (RPE) in AMD donor eyes suggesting that increased BACE1 is compensatory. We observed that AAV-mediated BACE1 overexpression in the RPE was maintained up to 6 months after AAV1-BACE1 administration. No significant changes in normal mouse visual function or retinal morphology were observed with low-dose vector while the high-dose vector demonstrated some early pathology which regressed with time. No increase in ß-amyloid was observed. BACE1 overexpression in the RPE of the superoxide dismutase 2 knockdown (SOD2 KD) mouse, which exhibits an AMD-like phenotype, prevented loss of retinal function and retinal pathology, and this was sustained out to 6 months. Furthermore, BACE1 overexpression was able to inhibit oxidative stress, microglial changes, and loss of RPE tight junction integrity (all features of AMD) in SOD2 KD mice. In conclusion, BACE1 plays a key role in retina/RPE homeostasis, and BACE1 overexpression offers a novel therapeutic target in the treatment of AMD.

Liquiritin alleviates alpha-naphthylisothiocyanate-induced intrahepatic cholestasis through the Sirt1/FXR/Nrf2 pathway.

Liquiritin (LQ) is an important monomer active component in flavonoids of licorice. The objective of this study was to evaluate the hepatoprotective effects of LQ in cholestatic mice. LQ (40 or 80 mg/kg) was intragastrically administered to mice once daily for 6 days, and mice were treated intragastrically with a single dosage of ANIT (75 mg/kg) on the 5th day. On the 7th day, mice were sacrificed to collect blood and livers. The mRNA and protein levels were determined by qRT-PCR and western blot assay. We also conducted systematical assessments of miRNAs expression profiles in the liver. LQ ameliorated ANIT-induced cholestatic liver injury, as evidenced by reduced serum biochemical markers and attenuated pathological changes in liver. Pretreatment of LQ reduced the increase of malondialdehyde, TNF-α, and IL-1ß induced by ANIT. Moreover, ANIT suppressed the expression of Sirt1 and FXR in liver tissue, which was weakened in the LQ pre-treatment group. LQ enhanced the nuclear expression of Nrf2, which was increased in the ANIT group. LQ also increased the mRNA expressions of bile acid transporters Bsep, Ntcp, Mrp3, and Mrp4. Furthermore, a miRNA deep sequencing analysis revealed that LQ had a global regulatory effect on the hepatic miRNA expression. Kyoto Encyclopedia of Genes and Genomes functional enrichment analysis showed that the differentially expressed miRNAs were mainly related to metabolic pathways, endocytosis, and MAPK signaling pathway. Collectively, LQ attenuated hepatotoxicity and cholestasis by regulating the expression of Sirt1/FXR/Nrf2 and the bile acid transporters, indicating that LQ might be an effective approach for cholestatic liver diseases.

Extracellular matrix turnover: phytochemicals target and modulate the dual role of matrix metalloproteinases (MMPs) in liver fibrosis.

Extracellular matrix (ECM) resolution by matrix metalloproteinases (MMPs) is a well-documented mechanism. MMPs play a dual and complex role in modulating ECM degradation at different stages of liver fibrosis, depending on the timing and levels of their expression. Increased MMP-1 combats disease progression by cleaving the fibrillar ECM. Activated hepatic stellate cells (HSCs) increase expression of MMP-2, -9, and -13 in different chemicals-induced animal models, which may alleviate or worsen disease progression based on animal models and the stage of liver fibrosis. In the early stage, elevated expression of certain MMPs may damage surrounding tissue and activate HSCs, promoting fibrosis progression. At the later stage, downregulation of MMPs can facilitate ECM accumulation and disease progression. A number of phytochemicals modulate MMP activity and ECM turnover, alleviating disease progression. However, the effects of phytochemicals on the expression of different MMPs are variable and may depend on the disease models and stage, and the dosage, timing and duration of phytochemicals used in each study. Here, we review the most recent advances in the role of MMPs in the effects of phytochemicals on liver fibrogenesis, which indicates that further studies are warranted to confirm and define the potential clinical efficacy of these phytochemicals.

MRI features of neuronal intranuclear inclusion disease, combining visual and quantitative imaging investigations.

OBJECTIVE: To observe the radiological characteristics of Neuronal Intranuclear Inclusion Disease (NIID) on lesion locations and diffusion property using quantitative imaging analysis. METHODS: Visual inspection and quantitative analyses were performed on MRI data from 31 retrospectively included patients with NIID. Frequency heatmaps of lesion locations on T2WI and DWI were generated using voxel-wise analysis. Gray matter volume (GMV), white matter volume (WMV) and diffusion property of apparent diffusion coefficient (ADC) values of patients were voxel-wisely compared with healthy controls. Moreover, the ADC values within the DWI-detected lesion were compared with those within the adjacent cortical gray matter and white matter. Voxel-based lesion symptom mapping (VLSM) techniques, were used to determine the relationship between DWI lesion location and disease durations. RESULTS: By visual inspection on the imaging findings, we proposed an "cockscomb flower sign" for describing the radiological feature of DWI hyperintensity within the corticomedullary junction. A "T2WI-DWI mismatch of spatial distribution" pattern was also revealed with visual inspection and frequency heatmaps, for describing the feature of a wider lesion distribution covering white matter shown on T2WI than that on DWI. Voxel-based morphometry comparison revealed that wildly reduced GMV and WMV, both the lesion areas detected by DWI and T2WI demonstrated ADC increase in patients. Furthermore, the ADC values within the DWI-detected lesion were intermediate between the adjacent cortex and the deep white matter with highest ADC. VLSM analysis revealed that frontal lobe, parietal lobe and internal capsule damage were associated with higher NIID durations. CONCLUSION: NIID features with "cockscomb flower-like" DWI hyperintensity in area of corticomedullary junction, based on a "T2WI-DWI mismatch of spatial distribution" of lesion locations. The pathological substrate of corticomedullary junction hyperintensity on DWI, can not be explained as diffusion restriction. These typical radiological features of brain MRI would be helpful for diagnosis of NIID.

Overexpression of Decay Accelerating Factor Mitigates Fibrotic Responses to Lung Injury.

CD55 or decay accelerating factor (DAF), a ubiquitously expressed glycosylphosphatidylinositol (GPI)-anchored protein, confers a protective threshold against complement dysregulation which is linked to the pathogenesis of idiopathic pulmonary fibrosis (IPF). Since lung fibrosis is associated with downregulation of DAF, we hypothesize that overexpression of DAF in fibrosed lungs will limit fibrotic injury by restraining complement dysregulation. Normal primary human alveolar type II epithelial cells (AECs) exposed to exogenous complement 3a or 5a, and primary AECs purified from IPF lungs demonstrated decreased membrane-bound DAF expression with concurrent increase in the endoplasmic reticulum (ER) stress protein, ATF6. Increased loss of extracellular cleaved DAF fragments was detected in normal human AECs exposed to complement 3a or 5a, and in lungs of IPF patients. C3a-induced ATF6 expression and DAF loss was inhibited using pertussis toxin (an enzymatic inactivator of G-protein coupled receptors), in murine AECs. Treatment with soluble DAF abrogated tunicamycin-induced C3a secretion and ER stress (ATF6 and BiP expression) and restored epithelial cadherin. Bleomycin-injured fibrotic mice subjected to lentiviral overexpression of DAF demonstrated diminished levels of local collagen deposition and complement activation. Further analyses showed diminished release of DAF fragments, as well as reduction in apoptosis (TUNEL and caspase 3/7 activity), and ER stress-related transcripts. Loss-of-function studies using Daf1 siRNA demonstrated worsened lung fibrosis detected by higher mRNA levels of Col1a1 and epithelial injury-related Muc1 and Snai1, with exacerbated local deposition of C5b-9. Our studies provide a rationale for rescuing fibrotic lungs via DAF induction that will restrain complement dysregulation and lung injury.

Allele-specific expression and high-throughput reporter assay reveal functional genetic variants associated with alcohol use disorders.

Genome-wide association studies (GWAS) of complex traits, such as alcohol use disorders (AUD), usually identify variants in non-coding regions and cannot by themselves distinguish whether the associated variants are functional or in linkage disequilibrium with the functional variants. Transcriptome studies can identify genes whose expression differs between alcoholics and controls. To test which variants associated with AUD may cause expression differences, we integrated data from deep RNA-seq and GWAS of four postmortem brain regions from 30 subjects with AUD and 30 controls to analyze allele-specific expression (ASE). We identified 88 genes with differential ASE in subjects with AUD compared to controls. Next, to test one potential mechanism contributing to the differential ASE, we analyzed single nucleotide polymorphisms (SNPs) in the 3' untranslated regions (3'UTR) of these genes. Of the 88 genes with differential ASE, 61 genes contained 437 SNPs in the 3'UTR with at least one heterozygote among the subjects studied. Using a modified PASSPORT-seq (parallel assessment of polymorphisms in miRNA target-sites by sequencing) assay, we identified 25 SNPs that affected RNA levels in a consistent manner in two neuroblastoma cell lines, SH-SY5Y and SK-N-BE(2). Many of these SNPs are in binding sites of miRNAs and RNA-binding proteins, indicating that these SNPs are likely causal variants of AUD-associated differential ASE. In sum, we demonstrate that a combination of computational and experimental approaches provides a powerful strategy to uncover functionally relevant variants associated with the risk for AUD.

A novel long excitation/emission wavelength fluorophore as platform utilized to construct NIR probes for bioimaging and biosensing.

Near-infrared (NIR) fluorophores, especially dicyano-based fluorophores and xanthene-based hemicyanines, have beenput high expectation in bioimaging application due to their excellent optical properties. However, they suffer from inherentshortagessuch as short excitation/emission wavelength (less than 700 nm) or small Stokes shift (20-50 nm). Herein, we constructed a novel NIR dicyano-based fluorophore (DCO-HBTN). Toourknowledge, it is the first reported dicyano-based fluorophore of which the excitation/emission wavelength is more than 650 nm and Stokes shift is more than 100 nm. To demonstrate the feasibility of our efforts, we developed two NIR fluorescent probes (Probe-Cys and Probe-H2S) based on the fluorophore, Probe-Cys displayed good selective and highly sensitive (LOD = 0.28 µM) recognition of Cys over Hcy and GSH, which was used to visualize endogenous Cys in tumor tissue. Probe-H2S exhibited an. excellent specific and sensitive (LOD = 0.11 µM) response to H2S, which was applied in monitoring H2S releasing from the prodrug in vitro and in vivo.

Atherosclerosis-associated hepatic secretion of VLDL but not PCSK9 is dependent on cargo receptor protein Surf4.

Plasma LDL is produced from catabolism of VLDL and cleared from circulation mainly via the hepatic LDL receptor (LDLR). Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDLR degradation, increasing plasma LDL-C levels. Circulating PCSK9 is mainly secreted by the liver, whereas VLDL is exclusively secreted by hepatocytes. However, the mechanism regulating their secretion is not completely understood. Surfeit 4 (Surf4) is a cargo receptor localized in the ER membrane. It recruits cargos into coat protein complex II vesicles to facilitate their secretion. Here, we investigated the role of Surf4 in VLDL and PCSK9 secretion. We generated Surf4 liver-specific knockout mice and found that knockout of Surf4 did not affect PCSK9 secretion, whereas it significantly reduced plasma levels of cholesterol, triglyceride, and lipid-binding protein apolipoprotein B (apoB). In cultured human hepatocytes, Surf4 coimmunoprecipitated and colocalized with apolipoprotein B100, and Surf4 silencing reduced secretion of apolipoprotein B100. Furthermore, knockdown of Surf4 in LDLR knockout (Ldlr-/-) mice significantly reduced triglyceride secretion, plasma levels of apoB and non-HDL-C, and the development of atherosclerosis. However, Surf4 liver-specific knockout mice and Surf4 knockdown in Ldlr-/- mice displayed similar levels of liver lipids and plasma alanine aminotransferase activity as control mice, indicating that inhibition of Surf4 does not cause notable liver damage. Expression of stearoyl-CoA desaturase-1 was also reduced in the liver of these mice, suggesting a reduction in de novo lipogenesis. In summary, hepatic deficiency of Surf4 reduced VLDL secretion and the development of atherosclerosis but did not cause significant hepatic lipid accumulation or liver damage.

Analysis of lncRNA-mRNA networks after MEK1/2 inhibition based on WGCNA in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDA) responds poorly to treatment. Efforts have been exerted to prolong the survival time of PDA, but the 5-year survival rates remain disappointing. Understanding the molecular mechanisms of PDA development is significant. MEK/ERK pathway signaling has been proven to be important in PDA. lncRNA-mRNA networks have become a vital part of molecular mechanisms in the MEK/ERK pathway. Herein, weighted gene coexpression network analysis was used to investigate the coexpressed lncRNA-mRNA networks in the MEK/ERK pathway based on GSE45765. Differently expressed long noncoding RNA (lncRNA) and messenger RNA (mRNA) were found and 10 modules were identified based on coexpression profiles. Gene ontology and Kyoto Encyclopedia of Genes and Genomes were then performed to analyze the coexpressed lncRNA and mRNA in different modules. PDA cells and tissues were used to validate the analysis results. Finally, we found that NONHSAT185150.1 and B4GALT6 were negatively correlated with MEK1/2. By analyzing GSE45765, the genome-wide profiles of lncRNA-mRNA network after MEK1/2 was established, which might aid the development of drug-targeting MEK1/2 and the investigation of diagnostic markers.

Circular RNA_LARP4 Sponges miR-1323 and Hampers Progression of Esophageal Squamous Cell Carcinoma Through Modulating PTEN/PI3K/AKT Pathway.

BACKGROUND: Emerged as important regulators in cancer progression, circular RNAs have been tested to participate in diverse biological processes. Former studies have suggested that circular RNA_LARP4 (circLARP4) exerts indispensable function on the development of different cancers such as gastric cancer and ovarian cancer. Nonetheless, the specific role of circLARP4 has not been discovered in ESCC. AIMS: The aim of this study is to explore the biological function and regulatory mechanism of circLARP4 in ESCC. METHODS: CircLARP4, miR-1323, and PTEN expression levels were quantified by RT-qPCR. CCK-8, EdU, caspase-3 activity, wound healing, transwell, and western blot assays were chosen to assess ESCC cell growth. Luciferase reporter, RIP, and RNA pull-down assays were performed to examine the interaction between miR-1323 and circLARP4 (or PTEN). RESULTS: CircLARP4 expression was observably downregulated in ESCC cell lines, and overexpressed circLARP4 restrained cell proliferation and migration whereas boosted cell apoptosis in ESCC. Molecular mechanism experiments revealed that circLARP4 could act as a sponge for miR-1323 and negatively modulated miR-1323 expression in ESCC. Interestingly, the repression of miR-1323 was correlated with inhibitive cell proliferation, migration, and promotive apoptosis. Besides, miR-1323 bound with PTEN, and PTEN expression was negatively regulated by miR-1323 whereas positively regulated by circLARP4 in ESCC. Moreover, rescue assays testified that miR-1323 overexpression or PTEN deficiency could countervail the function of circLARP4 overexpression on ESCC progression. More importantly, circLARP4 played an inhibitory role in PI3K/AKT pathway. CONCLUSIONS: CircLARP4 sponges miR-1323 and hampers tumorigenesis of ESCC through modulating PTEN/PI3K/AKT pathway.

Value of T1 mapping on gadoxetic acid-enhanced MRI for microvascular invasion of hepatocellular carcinoma: a retrospective study.

BACKGROUND: To evaluate the utility of non-invasive parameters derived from T1 mapping and diffusion-weighted imaging (DWI) on gadoxetic acid-enhanced MRI for predicting microvascular invasion (MVI) of hepatocellular carcinoma (HCC). METHODS: A total of 94 patients with single HCC undergoing partial hepatectomy was analyzed in this retrospective study. Preoperative T1 mapping and DWI on gadoxetic acid-enhanced MRI was performed. The parameters including precontrast, postcontrast and reduction rate of T1 relaxation time and apparent diffusion coefficient (ADC) values were measured for differentiating MVI-positive HCCs (n = 38) from MVI-negative HCCs (n = 56). The receiver operating characteristic curve (ROC) was analyzed to compare the diagnostic performance of the calculated parameters. RESULTS: MVI-positive HCCs demonstrated a significantly lower reduction rate of T1 relaxation time than that of MVI-negative HCCs (39.4% vs 49.9, P < 0.001). The areas under receiver operating characteristic curve (AUC) were 0.587, 0.728, 0.824, 0,690 and 0.862 for the precontrast, postcontrast, reduction rate of T1 relaxation time, ADC and the combination of reduction rate and ADC, respectively. The cut-off value of the reduction rate and ADC calculated through maximal Youden index in ROC analyses was 44.9% and 1553.5 s/mm2. To achieve a better diagnostic performance, the criteria of combining the reduction rate lower than 44.9% and the ADC value lower than 1553.5 s/mm2 was proposed with a high specificity of 91.8% and accuracy of 80.9%. CONCLUSIONS: The proposed criteria of combining the reduction rate of T1 relaxation time lower than 44.9% and the ADC value lower than 1553.5 s/mm2 on gadoxetic acid-enhanced MRI holds promise for evaluating MVI status of HCC.

Proprotein Convertase Subtilisin/Kexin-Type 9 and Lipid Metabolism.

Plasma levels of cholesterol, especially low-density lipoprotein cholesterol (LDL-C), are positively correlated with the risk of cardiovascular disease. Buildup of LDL in the intima promotes the formation of foam cells and consequently initiates atherosclerosis, one of the main underlying causes of cardiovascular disease. Hepatic LDL receptor (LDLR) is mainly responsible for the clearance of plasma LDL. Mutations in LDLR cause familiar hypercholesterolemia and increase the risk of premature coronary heart disease. Proprotein convertase subtilisin/kexin-type 9 (PCSK9) promotes LDLR degradation and thereby plays a critical role in the regulation of plasma cholesterol metabolism. PCSK9 can bind to LDLR and reroute the receptor to lysosomes for degradation, increasing both circulating LDL-C levels and the risk of cardiovascular disease. PCSK9 is mainly regulated by sterol response element binding protein 2 (SREBP2) at the transcriptional level. Furthermore, many proteins have been identified as interacting with PCSK9, regulating plasma cholesterol levels. Pharmacotherapeutic inhibition of PCSK9 dramatically reduces plasma levels of LDL cholesterol and significantly reduces cardiovascular events. In this article, we summarize the latest advances in PCSK9, mainly focusing on the structure, function, and regulation of the protein, the underlying molecular mechanisms, and its pharmacotherapeutic applications.

Identification of amino acid residues in the ligand binding repeats of LDL receptor important for PCSK9 binding.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDL receptor (LDLR) degradation, increasing plasma levels of LDL cholesterol and the risk of cardiovascular disease. We have previously shown that, in addition to the epidermal growth factor precursor homology repeat-A of LDLR, at least three ligand-binding repeats (LRs) of LDLR are required for PCSK9-promoted LDLR degradation. However, how exactly the LRs contribute to PCSK9's action on the receptor is not completely understood. Here, we found that substitution of Asp at position 172 in the linker between the LR4 and LR5 of full-length LDLR with Asn (D172N) reduced PCSK9 binding at pH 7.4 (mimic cell surface), but not at pH 6.0 (mimic endosomal environment). On the other hand, mutation of Asp at position 203 in the LR5 of full-length LDLR to Asn (D203N) significantly reduced PCSK9 binding at both pH 7.4 and pH 6.0. D203N also significantly reduced the ability of LDLR to mediate cellular LDL uptake, whereas D172N had no detectable effect. These findings indicate that amino acid residues in the LRs of LDLR play an important role in PCSK9 binding to the receptor.

Efficacy and safety of magnesium isoglycyrrhizinate injection in patients with acute drug-induced liver injury: A phase II trial.

BACKGROUND: Drug-induced liver injury (DILI) is the most common reason for a drug to be withdrawn from the market. Apart from stopping the offending drug, no regimens are available for treating idiosyncratic DILI in clinical practice. METHODS: We carried out a randomized, double-blind, multidoses, active drug controlled, multicentre phase II trial to assess the safety and efficacy of the study drug, magnesium isoglycyrrhizinate (MgIG), as compared to tiopronin, a standard therapy for DILI in China. The primary outcome was the proportion of alanine aminotransferase (ALT) normalization at week 4 after study drug administration. Logistic regression was used to examine the odds of ALT normalization between low dose (Group A) and high dose (Group B) vs active control (Group C). RESULTS: One hundred and seventy-four eligible subjects were randomized and enrolled into three groups: 59 in group A, 56 in group B and 59 in group C. It was shown that group A and group B lowered ALT level even at early stage of study drug administration; when compared with Group C (61.02%), the proportions of ALT normalization at week 4 were significantly greater in Group A (84.75%, P = .0029) and Group B (85.71%, P = .0037) respectively. The results from the univariate logistic model showed that the odds of ALT normalized among subjects in Group A were about 3.6 times greater (OR = 3.55, 95% CI: 1.47-8.57, P = .0049) than subjects in Group C. Similar effect was observed among subjects in Group B (OR = 3.83, 95% CI: 1.54-9.55, P = .0039). CONCLUSIONS: This trial provided preliminary evidence that MgIG is an effective and safe treatment for patients with acute DILI.

Magnesium isoglycyrrhizinate ameliorates high fructose-induced liver fibrosis in rat by increasing miR-375-3p to suppress JAK2/STAT3 pathway and TGF-ß1/Smad signaling.

Increasing evidence has demonstrated that excessive fructose intake induces liver fibrosis. Epithelial-mesenchymal transition (EMT) driven by transforming growth factor-ß1 (TGF-ß1)/mothers against decapentaplegic homolog (Smad) signaling activation promotes the occurrence and development of liver fibrosis. Magnesium isoglycyrrhizinate is clinically used as a hepatoprotective agent to treat liver fibrosis, but its underlying molecular mechanism has not been identified. Using a rat model, we found that high fructose intake reduced microRNA (miR)-375-3p expression and activated the janus-activating kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) cascade and TGF-ß1/Smad signaling, which is consistent with the EMT and liver fibrosis. To further verify these observations, BRL-3A cells and/or primary rat hepatocytes were exposed to high fructose and/or transfected with a miR-375-3p mimic or inhibitor or treated with a JAK2 inhibitor, and we found that the low expression of miR-375-3p could induce the JAK2/STAT3 pathway to activate TGF-ß1/Smad signaling and promote the EMT. Magnesium isoglycyrrhizinate was found to ameliorate high fructose-induced EMT and liver fibrosis in rats. More importantly, magnesium isoglycyrrhizinate increased miR-375-3p expression to suppress the JAK2/STAT3 pathway and TGF-ß1/Smad signaling in these animal and cell models. This study provides evidence showing that magnesium isoglycyrrhizinate attenuates liver fibrosis associated with a high fructose diet.

[Impact of subchronic exposure to low-dose nano-nickel oxide on the reproductive function and offspring of male rats].

OBJECTIVE: To investigate the influence of subchronic exposure to low-dose subchronic nano-nickel oxide (NNO) on the reproductive function of male rats and embryonic development of the pregnant rats. METHODS: Fifty normal healthy male SD rats weighing 180－220 g were randomly divided into five groups of equal number, negative control, 4 mg/ml micro-nickel oxide (MNO), and 0.16, 0.8 and 4 mg/ml NNO, those of the latter four groups exposed to MNO or NNO by non-contact intratracheal instillation once every 3 days for 60 days, and then all mated with normal adult female rats in the ratio of 1∶2. After the female animals were confirmed to be pregnant, the males were sacrificed and the weights of the body, testis and epididymis obtained, followed by calculation of the visceral coefficients, determination of epididymal sperm concentration and viability and the nickel contents in the blood and semen by atomic fluorescence spectrometry. The female rats were killed on the 20th day of gestation for counting of the implanted fertilized eggs and live, dead and resorbed fetuses. RESULTS: After 60 days of exposure, the rats of the NNO groups showed no statistically significant differences from those of the negative control and MNO groups in the weights of the body, testis and epididymis or visceral coefficients. Compared with the negative control group, the animals of the 0.8 and 4 mg/ml NNO groups exhibited markedly decreased sperm concentration (ï¼»9.36 ± 0.98ï¼½ vs ï¼»7.49 ± 1.46ï¼½ and ï¼»6.30 ± 1.36ï¼½ ×106/ml, P < 0.05) and viable sperm (ï¼»85.35 ± 9.16ï¼½% vs ï¼»68.26 ± 16.63ï¼½% and ï¼»65.88 ± 14.68ï¼½ %, P < 0.05), increased morphologically abnormal sperm (ï¼»8.30 ± 2.47ï¼½% vs ï¼»13.99 ± 4.87ï¼½% and ï¼»15.38 ± 8.86ï¼½ %, P < 0.05), and elevated rate of dead and resorbed fetuses (1.18% vs 6.89% and 7.37%, P < 0.05), blood nickel content (ï¼»0.13 ± 0.16ï¼½ vs ï¼»0.52 ± 0.34ï¼½ and ï¼»0.82 ± 0.44ï¼½ mg/L, P < 0.05) and semen nickel content (ï¼»0.08 ± 0.13ï¼½ vs ï¼»0.35 ± 0.23ï¼½ and ï¼»0.63 ± 0.61ï¼½ mg/L, P < 0.05). The nickel level in the semen was correlated significantly with that in the blood (r = 0.912, P <0.01), negatively with the rate of viable sperm (r = －0.879, P <0.01) and positively with the percentage of morphologically abnormal sperm (r = －0.898, P <0.01). CONCLUSIONS: Sixty-day exposure to nano-nickel oxide at 0.8 and 4 mg/ml can produce reproductive toxicity in male rats and result in fetal abnormality in the females, while that at 0.16 mg/ml has no significant toxic effect on the reproductive function of the males.

Circular RNA circPVT1 Promotes Proliferation and Invasion Through Sponging miR-125b and Activating E2F2 Signaling in Non-Small Cell Lung Cancer.

BACKGROUND/AIMS: Circular RNAs (circRNAs) are key regulators in the development and progression of human cancers, however its role in non-small cell lung cancer (NSCLC) tumorigenesis is not well understood. The aim of this study is to identify the expression level of circPVT1 in NSCLC and further investigated its functional relevance with NSCLC progression both in vitro and in vivo. METHODS: Quantative real-time PCR was used for the measurement of circPVT1 in NSCLC specimens and cell lines. Fluorescence in situ hybridization analysis (FISH) assay was used for the identification of sublocation of circPVT1 in NSCLC cells. Bioinformatics analysis, luciferase reporter assay and RNA immunoprecipitation (RIP) were performed to verify the binding of c-Fos at circPVT1 promoter region, and the direct interaction between circPVT1 and miR-125b. Gain- or loss-function assays were performed to evaluate the effects of circPVT1 on cell proliferation and invasion. Western blot and immunohistochemistry assays were performed to detect the protein levels involved in E2F2 pathway. RESULTS: We found that circPVT1 was upregulated in NSCLC specimens and cells. The transcription factor c-Fos binded to the promoter region of circPVT1, resulting in the overexpression of circPVT1 in NSCLC. Knockdown of circPVT1 suppressed NSCLC cell proliferation, migration and invasion, and increased apoptosis. In addition, circPVT1 mediated NSCLC progression via the regulation of E2F2 signaling pathway. More importantly, circPVT1 was predominantly abundant in the cytoplasm of NSCLC cells, and circPVT1 could serve as a competing endogenous RNA to regulate E2F2 expression and tumorigenesis in a miR-125b-dependent manner, which is further verified by using an in vivo xenograft model. CONCLUSION: circPVT1 promotes NSCLC cell growth and invasion, and may serve as a promising therapeutic target for NSCLC patients. Therefore, silence of circPVT1 could be a future direction to develop a novel treatment strategy.

IL-17A deficiency mitigates bleomycin-induced complement activation during lung fibrosis.

Interleukin 17A (IL-17A) and complement (C') activation have each been implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). We have reported that IL-17A induces epithelial injury via TGF-ß in murine bronchiolitis obliterans; that TGF-ß and the C' cascade present signaling interactions in mediating epithelial injury; and that the blockade of C' receptors mitigates lung fibrosis. In the present study, we investigated the role of IL-17A in regulating C' in lung fibrosis. Microarray analyses of mRNA isolated from primary normal human small airway epithelial cells indicated that IL-17A (100 ng/ml; 24 h; n = 5 donor lungs) induces C' components (C' factor B, C3, and GPCR kinase isoform 5), cytokines (IL8, -6, and -1B), and cytokine ligands (CXCL1, -2, -3, -5, -6, and -16). IL-17A induces protein and mRNA regulation of C' components and the synthesis of active C' 3a (C3a) in normal primary human alveolar type II epithelial cells (AECs). Wild-type mice subjected to IL-17A neutralization and IL-17A knockout (il17a-/- ) mice were protected against bleomycin (BLEO)-induced fibrosis and collagen deposition. Further, BLEO-injured il17a-/- mice had diminished levels of circulating Krebs Von Den Lungen 6 (alveolar epithelial injury marker), local caspase-3/7, and local endoplasmic reticular stress-related genes. BLEO-induced local C' activation [C3a, C5a, and terminal C' complex (C5b-9)] was attenuated in il17a-/- mice, and IL-17A neutralization prevented the loss of epithelial C' inhibitors (C' receptor-1 related isoform Y and decay accelerating factor), and an increase in local TUNEL levels. RNAi-mediated gene silencing of il17a in fibrotic mice arrested the progression of lung fibrosis, attenuated cellular apoptosis (caspase-3/7) and lung deposition of collagen and C' (C5b-9). Compared to normals, plasma from IPF patients showed significantly higher hemolytic activity. Our findings demonstrate that limiting complement activation by neutralizing IL-17A is a potential mechanism in ameliorating lung fibrosis.-Cipolla, E., Fisher, A. J., Gu, H., Mickler, E. A., Agarwal, M., Wilke, C. A., Kim, K. K., Moore, B. B., Vittal, R. IL-17A deficiency mitigates bleomycin-induced complement activation during lung fibrosis.

Contribution of the anaphylatoxin receptors, C3aR and C5aR, to the pathogenesis of pulmonary fibrosis.

Complement activation, an integral arm of innate immunity, may be the critical link to the pathogenesis of idiopathic pulmonary fibrosis (IPF). Whereas we have previously reported elevated anaphylatoxins-complement component 3a (C3a) and complement component 5a (C5a)-in IPF, which interact with TGF-ß and augment epithelial injury in vitro, their role in IPF pathogenesis remains unclear. The objective of the current study is to determine the mechanistic role of the binding of C3a/C5a to their respective receptors (C3aR and C5aR) in the progression of lung fibrosis. In normal primary human fetal lung fibroblasts, C3a and C5a induces mesenchymal activation, matrix synthesis, and the expression of their respective receptors. We investigated the role of C3aR and C5aR in lung fibrosis by using bleomycin-injured mice with fibrotic lungs, elevated local C3a and C5a, and overexpression of their receptors via pharmacologic and RNA interference interventions. Histopathologic examination revealed an arrest in disease progression and attenuated lung collagen deposition (Masson's trichrome, hydroxyproline, collagen type I α 1 chain, and collagen type I α 2 chain). Pharmacologic or RNA interference-specific interventions suppressed complement activation (C3a and C5a) and soluble terminal complement complex formation (C5b-9) locally and active TGF-ß1 systemically. C3aR/C5aR antagonists suppressed local mRNA expressions of tgfb2, tgfbr1/2, ltbp1/2, serpine1, tsp1, bmp1/4, pdgfbb, igf1, but restored the proteoglycan, dcn Clinically, compared with pathologically normal human subjects, patients with IPF presented local induction of C5aR, local and systemic induction of soluble C5b-9, and amplified expression of C3aR/C5aR in lesions. The blockade of C3aR and C5aR arrested the progression of fibrosis by attenuating local complement activation and TGF-ß/bone morphologic protein signaling as well as restoring decorin, which suggests a promising therapeutic strategy for patients with IPF.-Gu, H., Fisher, A. J., Mickler, E. A., Duerson, F., III, Cummings, O. W., Peters-Golden, M., Twigg, H. L., III, Woodruff, T. M., Wilkes, D. S., Vittal, R. Contribution of the anaphylatoxin receptors, C3aR and C5aR, to the pathogenesis of pulmonary fibrosis.