Insulin-like growth factor binding protein related protein 1 knockdown attenuates hepatic ?brosis via the regulation of MMPs/TIMPs in mice

Background: Previous research suggested that insulin-like growth factor binding protein related protein 1(IGFBPrP1), as a novel mediator, contributes to hepatic fibrogenesis. Matrix metalloproteinases(MMP) and tissue inhibitors of metalloproteinases(TIMP) play an essential role in hepatic fibrogenesis by regulating homeostasis and remodeling of the extracellular matrix(ECM). However, the interaction between IGFBPrP1 and MMP/TIMP is not clear. The present study was to knockdown IGFBPrP1 to investigate the correlation between IGFBPrP1 and MMP/TIMP in hepatic fibrosis. Methods: Hepatic fibrosis was induced by thioacetamide(TAA) in mice. Knockdown of IGFBPrP1 expression by ultrasound-targeted microbubble destruction-mediated CMB-shRNA-IGFBPrP1 delivery, or inhibition of the Hedgehog(Hh) pathway by cyclopamine treatment, was performed in TAA-induced liver fibrosis mice. Hepatic fibrosis was determined by hematoxylin and eosin and Sirius red staining. Hepatic expression of IGFBPrP1, α-smooth muscle actin( α-SMA), transforming growth factor β 1(TGF β1), collagen I, MMPs/TIMPs, Sonic Hedgehog(Shh), and glioblastoma family transcription factors(Gli1) were investigated by immunohistochemical staining and Western blotting analysis. Results: We found that hepatic expression of IGFBPrP1, TGF β1, α-SMA, and collagen I were increased longitudinally in mice with TAA-induced hepatic fibrosis, concomitant with MMP2/TIMP2 and MMP9/TIMP1 imbalance and Hh pathway activation. Knockdown of IGFBPrP1 expression, or inhibition of the Hh pathway, reduced the hepatic expression of IGFBPrP1, TGF β1, α-SMA, and collagen I and re-established MMP2/TIMP2 and MMP9/TIMP1 balance. Conclusions: Our findings suggest that IGFBPrP1 knockdown attenuates liver fibrosis by re-establishing MMP2/TIMP2 and MMP9/TIMP1 balance, concomitant with the inhibition of hepatic stellate cell activation, down-regulation of TGF β1 expression, and degradation of the ECM. Furthermore, the Hh pathway mediates IGFBPrP1 knockdown-induced attenuation of hepatic fibrosis through the regulation of MMPs/TIMPs balance.

Interaction between insulin-like growth factor binding protein-related protein 1 and transforming growth factor beta 1 in primary hepatic stellate cells

BACKGROUND: We previously showed that insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) is a novel mediator in liver fibrosis. Transforming growth factor beta 1 (TGF beta 1) is known as the strongest effector of liver fibrosis. Therefore, we aimed to investigate the detailed interaction between IGFBPrP1 and TGF beta 1 in primary hepatic stellate cells (HSCs). METHODS: We overexpressed TGF beta 1 or IGFBPrP1 and inhibited TGF beta 1 expression in primary HSCs for 6, 12, 24, 48, 72, and 96 hours to investigate their interaction and observe the accompanying expressions of a-smooth muscle actin (alpha-SMA), collagen I, fibronectin, and phosphorylated-mothers against decapentaplegic homolog 2/3 (p-Smad2/3). RESULTS: We found that the adenovirus vector encoding the TGF beta 1 gene (AdTGF beta 1) induced IGFBPrP1 expression while that of alpha-SMA, collagen I, fibronectin, and TGF beta 1 increased gradually. Concomitantly, AdIGFBPrP1 upregulated TGF beta 1, alpha-SMA, collagen I, fibronectin, and p-Smad2/3 in a time-dependent manner while IGFBPrP1 expression was decreased at 96 hours. Inhibition of TGF beta 1 expression reduced the IGFBPrP1-stimulated expression of alpha-SMA, collagen I, fibronectin, and p-Smad2/3. CONCLUSIONS: These findings for the first time suggest the existence of a possible mutually regulation between IGFBPrP1 and TGF beta 1, which likely accelerates liver fibrosis progression. Furthermore, IGFBPrP1 likely participates in liver fibrosis in a TGF beta 1-depedent manner, and may act as an upstream regulatory factor of TGF beta 1 in the Smad pathway.

Insulin-like growth factor binding protein 1 and human embryonic development during 6-10 gestational weeks

Background Insulin-like growth factor binding protein-1 (IGFBP-1), which is a carrier of Insulin-like growth factors (IGFs) regulates the fetal development by working as an active factor controlling the combination of IGFs with their receptors. This study was designed to investigate the relationship between IGFBP-1 and human embryonic development during weeks 6-10 of gestation. Methods A total of 44 pregnant women with singleton pregnancy were divided into two groups: one with abnormal embryo development (n=32) and the other with normal embryo development (n=12). Enzyme-linked immunosorbent assay (ELISA) was employed to detect IGFBP-1 levels in maternal serum and decidual tissue. The expression of IGFBP-1 mRNA in deciduas was examined by reverse transcription polymerase chain reaction (RT-PCR) technique. Results The level of IGFBP-1 protein in maternal serum was significantly higher in the abnormal group [(125.36±47.93) μg/ml] than in the normal group [(70.72±21.21) μg/ml]. Both of IGFBP-1 and IGFBP-1 mRNA in deciduas were higher in abnormal group [(1.60±1.39) μg/ml and 1.66±1.64, respectively] than in the normal group [(0.35±0.23) μg/ml and 0.40±0.20, respectively]. The level of IGFBP-1 in maternal serum was positively correlated with IGFBP-1 mRNA (r=0.90, P<0.05) and IGFBP-1 protein (r=0.92, P<0.05) in decidual tissue. Conclusions During weeks 6-10 of gestation, abnormal embryonic development is correlated with elevated IGFBP-1. The level of IGFBP-1 in maternal serum is related to the concentrations of IGFBP-1 mRNA and IGFBP-1 in decidual tissue. The IGFBP-1 level in maternal serum may be used as a predictive marker to evaluate embryonic development.

Effects of insulin-like growth factor binding protein-related protein 1 in mice with hepatic fibrosis induced by thioacetamide

Background Insulin-like growth factor binding protein-related protein 1 （IGFBPrP1） can activate hepatic stellate cells and increase extracellular matrix （ECM） in vitro. However, the effects of IGFBPrP1 in mice with hepatic fibrosis, and the mechanisms of these effects, are currently unknown. We aim to address these issues in this study. Methods Intraperitoneal injection of thioacetamide （TAA） is a classic method for establishing a mouse model of hepatic fibrosis. Using this model, we administered anti-IGFBPrP1 antibody, again via intraperitoneal injection. The morphological changes of liver fibrosis were observed with both HE and Masson stainning. The immunohistochemical assays and Western blotting were used to measure changes in IGFBPrP1, a-smooth muscle actin （a-SMA） and ECM in liver tissues, and the expression of transforming growth factor-β1 （TGF-β1） and Smad3. Data were statistically analyzed using one-way analysis of variance （ANOVA）, the SNK-q test for inter-group differences. Results The Masson staining analysis showed that compared with normal control group, content of collagen fiber in TAA5w group was significantly increased （P 〈0.01）, and it was significantly decreased in TAA5w/alGFBPrP1 group compared with in TAA5w group （P 〈0.01）. The expression of hepatic IGFBPrP1, a-SMA, TGF-β1, Smad3, collagen 1 and fibronectin （FN） was significantly up-regulated in the TAA5w group （P 〈0.01）. Anti-IGFBPrP1 treatment reversed these changes （P 〈0.01）. Conclusions IGFBPrP1 plays an important role in the development of hepatic fibrosis. Anti-IGFBPrP1 prevents fibrosis in mice by suppressing the activation of hepatic stellate cells, inhibiting the synthesis of major components of the ECM （namely, collagen I and FN）. The mechanism for this suppression of fibrosis is associated with the TGF-β1/Smad3 signaling pathways.

Insulin-like growth factor binding proteins 7 prevents dental pulp-derived mesenchymal stem cell senescence via metabolic downregulation of p21

Cellular senescence affects the efficacy of mesenchymal stem cells(MSCs)-mediated tissue regeneration.Insulin-like growth factor binding proteins-7(IGFBP7),as a member of the IGF family,is associated with osteogenic differentiation and the senescence of MSCs,but its exact function and mechanism remain unclear.We found IGFBP7 promoted the osteogenic differentiation and prevented the senescence of dental pulp-derived MSCs(DPSCs),as observed in the gain-of-function and lossof-function analyses,the senescence-associated marker p21 showed the most pronounced expression changes.We demonstrated that IGFBP7 activated the biological activity of SIRT1 deacetylase via metabolism,resulting in a deacetylation of H3K36ac and a decrease of the binding affinity of H3K36ac to p21 promoter,thereby reducing the transcription of p21,which ultimately prevents DPSCs senescence and promotes tissue regeneration.The activation of the mitochondrial electron transport chain(ETC)by Coenzyme Q10 could rescue the promotion of DPSC senescence induced by the knockdown of IGFBP7,whereas the inhibition of ETC by rotenone attenuated the prevention of DPSC senescence induced by IGFBP7 overexpression.In conclusion,our present results reveal a novel function of IGFBP7 in preventing DPSC senescence via the metabolism-induced deacetylation of H3K36ac and reduction of p21 transcription,suggesting that IGFBP7 is a potential target for promoting tissue regeneration in an aging environment.

N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer

BACKGROUND N6-methyladenosine(m6A)methylation modification exists in Epstein-Barr virus(EBV)primary infection,latency,and lytic reactivation.It also modifies EBV latent genes and lytic genes.EBV-associated gastric cancer(EBVaGC)is a distinctive molecular subtype of GC.We hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of GC.AIM To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of GC.METHODS First,The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC(EBVnGC).Second,we identified Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment of m6A-related differentially expressed genes.We quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment(TME).Finally,cell counting kit-8 cell proliferation test,transwell test,and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1(IGFBP1)in EBVaGC cell lines.RESULTS m6A methylation regulators were involved in the occurrence and development of EBVaGC.Compared with EBVnGC,the expression levels of m6A methylation regulators Wilms tumor 1-associated protein,RNA binding motif protein 15B,CBL proto-oncogene like 1,leucine rich pentatricopeptide repeat containing,heterogeneous nuclear ribonucleoprotein A2B1,IGFBP1,and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC(P<0.05).The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher(P=0.046).GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in EBVaGC.Compared with EBVnGC,the infiltration of activated CD4+T cells,activated CD8+T cells,monocytes,activated dendritic cells,and plasmacytoid dendritic cells were significantly upregulated in EBVaGC(P<0.001).In EBVaGC,the expression level of proinflammatory factors interleukin(IL)-17,IL-21,and interferon-γ and immunosuppressive factor IL-10 were significantly increased(P<0.05).In vitro experiments demonstrated that the expression level of IGFBP1 was significantly lower in an EBVaGC cell line(SNU719)than in an EBVnGC cell line(AGS)(P<0.05).IGFBP1 overexpression significantly attenuated proliferation and migration and promoted the apoptosis levels in SNU719.Interfering IGFBP1 significantly promoted proliferation and migration and attenuated the apoptosis levels in AGS.CONCLUSION m6A regulators could remodel the TME of EBVaGC,which is classified as an immune-inflamed phenotype and referred to as a“hot”tumor.Among these regulators,we demonstrated that IGFBP1 affected proliferation,migration,and apoptosis.

沙颍河铅污染对儿童GH-IGF-1轴和体格发育的影响

目的：探讨沙颍河铅污染现状及其对儿童生长激素-胰岛素样生长因子-1（ GH-IGF-1）轴和体格发育的影响。方法：随机选择淮河沙颍河流域S县两个村庄作为调查点（依距河岸距离远近分别定为对照区和污染区）；原子吸收分光光度法检测河水和调查点饮用水及土壤中的铅含量。整群抽取两村庄小学8～13岁在校学生作为研究对象，伏安极谱法测定儿童血清铅含量；ELISA法检测儿童血清胰岛素样生长因子-1（ IGF-1）、胰岛素样生长因子结合蛋白3（IGFBP3）、生长激素（GH）和生长激素结合蛋白（GHBP）水平；电子体重计、身高坐高计、皮褶厚度计及Gulick卷尺分别测量体重、身高、皮褶厚度和胸围。结果：河水3个采样断面铅浓度均超过国家地表水水质标准Ⅴ级。污染区饮用水及土壤铅含量均高于对照区（ t＝2．663和2．300，P＜0．05）。污染区儿童血清铅含量高于对照区儿童（t＝3．227，P＝0．002）。污染区男孩身高、体重、皮褶厚度、胸围与对照区比较差异均无统计学意义（P均＞0．05）。两区女孩身高、体重和胸围差异均无统计学意义（P均＞0．05），但污染区女孩皮褶厚度高于对照区（t＝3．036，P＝0．003）。结论：沙颍河流域的饮用水中铅含量明显升高，污染区儿童血清GH-IGF-1轴相关因子水平受到影响。

IGFBPrP1 induces liver fibrosis by inducing hepatic stellate cell activation and hepatocyte apoptosis via Smad2/3 signaling

AIM: To investigate the role and mechanism of insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) in the development of liver fibrosis.

阻塞性腺样体和扁桃体肥大与胰岛素样生长因子系统

阻塞性腺样体和扁桃体肥大可能引起儿童生长发育异常,其病理生理机制尚不明确。本文就血清胰岛素样生长因子-1(insulin-likegrowthfactorI,IGF-1)/胰岛素样生长因子结合蛋白-3(insulin-likegrowthfactor-bindingprotein3,IGFBP-3)概况及其在阻塞性腺样体和扁桃体肥大患儿生长激素分泌异常诊断和疗效判断方面的意义进行综述。