Insulin-like growth factor 2 targets IGF1R signaling transduction to facilitate metastasis and imatinib resistance in gastrointestinal stromal tumors

BACKGROUND Gastrointestinal stromal tumors(GISTs)are typical gastrointestinal tract neoplasms.Imatinib is the first-line therapy for GIST patients.Drug resistance limits the long-term effectiveness of imatinib.The regulatory effect of insulin-like growth factor 2(IGF2)has been confirmed in various cancers and is related to resistance to chemotherapy and a worse prognosis.AIM To further investigate the mechanism of IGF2 specific to GISTs.METHODS IGF2 was screened and analyzed using Gene Expression Omnibus(GEO:GSE225819)data.After IGF2 knockdown or overexpression by transfection,the phenotypes(proliferation,migration,invasion,apoptosis)of GIST cells were characterized by cell counting kit 8,Transwell,and flow cytometry assays.We used western blotting to evaluate pathway-associated and epithelial-mesenchymal transition(EMT)-associated proteins.We injected transfected cells into nude mice to establish a tumor xenograft model and observed the occurrence and metastasis of GIST.RESULTS Data from the GEO indicated that IGF2 expression is high in GISTs,associated with liver metastasis,and closely related to drug resistance.GIST cells with high expression of IGF2 had increased proliferation and migration,invasiveness and EMT.Knockdown of IGF2 significantly inhibited those activities.In addition,OEIGF2 promoted GIST metastasis in vivo in nude mice.IGF2 activated IGF1R signaling in GIST cells,and IGF2/IGF1R-mediated glycolysis was required for GIST with liver metastasis.GIST cells with IGF2 knockdown were sensitive to imatinib treatment when IGF2 overexpression significantly raised imatinib resistance.Moreover,2-deoxy-D-glucose(a glycolysis inhibitor)treatment reversed IGF2 overexpressionmediated imatinib resistance in GISTs.CONCLUSION IGF2 targeting of IGF1R signaling inhibited metastasis and decreased imatinib resistance by driving glycolysis in GISTs.

Exosome-transported IncRNA H19 regulates insulin-like growth factor-1 via the H19/let-7a/insulin-like growth factor-1 receptor axis in ischemic stroke

LncRNA(long non-coding RNA) H19 is a transcript of the H19 gene that is expressed during embryogenesis.We previously discove red a role for circular lncRNA H19 in the onset and prognosis of cerebral ischemic stroke.In this study,we used serum from patients with ischemic stroke,and mouse and cell culture models to elucidate the roles of plasma and neuronal exosomes in the regulatory effect of lncRNA H19 on insulin-like growth factor-1 and its mechanism in ischemic stroke,using western blotting,quantitative real-time polymerase chain reaction,and enzyme-linked immunosorbent assays.Plasma exosomal IncRNA H19 was negatively associated with blood levels of insulin-like growth factor-1 in samples from patients with cerebral ischemic stroke.In a mouse model,levels of exosomal IncRNA H19 were positively correlated with plasma and cerebral lncRNA H19.In a cell co-culture model,we confirmed that IncRNA H19 was transported from neuro ns to astrocytes by exosomes to induce downregulation of insulin-like growth factor-1 through the H19/let-7 a/insulin-like growth factor-1 receptor axis.This study provides the first evidence for the transpo rtation of IncRNA H19 by exosomes and the relationship between IncRNA H19 and insulinlike growth factor-1.

Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis

BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have always been unsatisfactory.AIM To investigate the correlation between vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGFβ1)expression and prognosis in older adults with AML.METHODS This study enrolled 80 patients with AML(AML group),including 36 with complete response(AML-CR),23 with partial response(AML-PR),and 21 with no response(AML-NR).The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls.Kaplan-Meier analysis was performed to assess overall survival(OS)and progression-or disease-free survival(DFS).Prognostic risk factors were analyzed using a Cox proportional hazards model.RESULTS The AML group showed a VEGF level of 2.68±0.16.VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR(P<0.05).TGFβ1 expression in the AML group was 0.33±0.05.Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR(P<0.05).VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes,platelets,hemoglobin,and peripheral blood immature cells(P<0.05);Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression(P<0.05),whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels(P<0.05).VEGF,TGFβ1,and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS(P<0.05),while VEGF,TGFβ1,and white blood cell count were independent risk factors for DFS(P<0.05).CONCLUSION Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies.

益气化瘀汤联合羟苯磺酸钙治疗糖尿病肾病气虚血瘀证的疗效及对VEGF,IGF-1表达水平的影响研究

【目的】观察益气化瘀汤(由黄芪、山药、茯苓、炒芡实、旱莲草、金樱子、焦山楂、女贞子、丹参、益母草等组成)联合羟苯磺酸钙治疗糖尿病肾病(DN)气虚血瘀证的临床疗效及对血管内皮生长因子(VEGF)、胰岛素样生长因子1(IGF-1)的影响。【方法】将90例DN气虚血瘀证患者随机分为观察组和对照组,每组各45例。所有患者均接受基础降糖治疗和控制血压、调节脂代谢紊乱等治疗。在此基础上,对照组患者给予羟苯磺酸钙治疗,观察组患者在对照组的基础上联合益气化瘀汤治疗,疗程为3个月。观察2组患者治疗前后中医证候积分、肾功能指标及血清VEGF、IGF-1水平的变化情况,并评价2组患者的临床疗效。【结果】(1)疗效方面,治疗3个月后,观察组的总有效率为91.11%(41/45),对照组为75.56%(34/45),组间比较(χ2检验),观察组的疗效明显优于对照组(P<0.05)。(2)中医证候积分方面,治疗1个月和3个月后,2组患者的中医证候积分均较治疗前明显降低(P<0.05),且治疗3个月后又均较治疗1个月后明显降低(P<0.05);组间比较,观察组在治疗1个月和3个月后对中医证候积分的降低作用均明显优于对照组(P<0.01)。(3)肾功能指标方面,治疗后,2组患者的血肌酐(Scr)、尿素氮(BUN)、肾小球滤过率(GFR)等肾功能指标均较治疗前明显改善(P<0.05),且观察组对各项肾功能指标的改善作用均明显优于对照组(P<0.01)。(4)血清VEGF、IGF-1水平方面,治疗后,2组患者的血清VEGF、IGF-1水平均较治疗前明显降低(P<0.05),且观察组对血清VEGF、IGF-1水平的降低作用均明显优于对照组(P<0.01)。(5)治疗过程中,2组患者均无明显不良反应发生,具有较高的安全性。【结论】益气化瘀汤联合羟苯磺酸钙治疗DN气虚血瘀证患者疗效确切,可有效下调血清VEGF、IGF-1水平,明显改善患者肾功能,显著减轻患者临床症状,且具有较高的安全性。

3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术应用效果及对血清MMP-9和IGF-1水平的影响

目的:探究3D打印技术在经鼻蝶窦入路垂体腺瘤(PA)切除术的应用效果及对血清基质金属蛋白酶-9(MMP-9)和胰岛素样生长因子-1(IGF-1)水平的影响。方法:选取2020年5月至2022年5月秦皇岛市第一医院收治的84例PA患者,按照随机数表法将其分为观察组和对照组,每组42例。对照组行经鼻蝶窦入路垂体腺瘤切除术,观察组行经鼻蝶窦入路垂体腺瘤切除术联合应用3D打印技术,比较两组肿瘤切除效果、围术期指标、视力改善情况、MMP-9和IGF-1水平,以及鼻腔功能的鼻气道阻力(NAR)、T&T嗅觉测试评分及并发症。结果:观察组肿瘤切除效果优于对照组,差异有统计学意义(U=2.286,P<0.05);观察组手术时间、术中出血量及住院时间均少于对照组,差异有统计学意义(t=4.780、11.438、11.842,P<0.05);术后3 d、7 d时观察组血清MMP-9和IGF-1水平低于对照组,差异有统计学意义(F=7.526、4.985,P<0.05);术后1个月、3个月时观察组NAR及T&T嗅觉测试评分低于对照组,差异有统计学意义(F=6.359、8.436,P<0.05);两组视力视野改善情况及并发症发生率比较,差异无统计学意义(P>0.05)。结论:3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术可提高肿瘤切除效果,优化手术操作,减少创伤,有利于减轻疼痛,改善嗅觉功能与视力视野,并能降低血清MMP-9、IGF-1水平,且安全性较高。

营养干预对生长迟缓患儿血清IGF-1水平的影响探讨

目的 对本院收治的营养干预对生长迟缓患儿血清IGF-1水平的影响进行分析,为生长迟缓患儿营养干预措施的制定与优化提供依据。方法 以本院2021年4月-2022年4月期间就诊的40例0~3岁生长迟缓患儿作为观察组,同时选取40例0~3岁的正常儿童作为对照组。对观察组患儿进行营养干预,测定干预前后观察组患儿血清IGF-1水平相关生长指标,以对照组为参考,比较2组各项指标。结果 营养干预前,观察组血清IGF-1水平显著低于对照组(P<0.05)营养干预后,观察组血清IGF-1水平显著高于本组营养干预前差异有统计学意义(P<0.05),且与同时段的对照组相当差异无统计学意义(P>0.05)。此外,观察组营养干预后的生长指标(HtSDS、生长速率)均显著优于营养干预前差异有统计学意义(P<0.05)。结论 血清IGF-1水平是判断儿童生长迟缓情况的重要指标,通过早期个性化的营养干预可提升生长迟缓患儿血清IGF-1水平,促进其生长发育。

Insulin-like growth factor-binding protein-3 inhibits IGF-1-induced proliferation of human hepatocellular carcinoma cells

OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like growth factor-binding protein-3(IGFBP-3)suppresses HCC cell proliferation in both IGF-dependent and independent manners.The present study is to investigate whether treatment with exogenous IGFBP-3 inhibits bF GF and PDGF production and the cell proliferation of HCC cells.METHODS Cell Counting Kit 8 assay were designed to detect HCC cell proliferation,transcription factor early growth response-1(EGR1)involving in IGFBP-3 regulation of b FGF and PDGF were detected by RT-PCR and Western blot assays.Western blot assay was adopted to detect the IGFBP-3 regulating insulin-like growth factor 1 receptor(IGF-1R)signaling pathway.RESULTS The present study demonstrates that IGFBP-3 suppressed IGF-1-induced b FGF and PDGF expression while it does not affect their expression in the absence of IGF-1.To delineate the underlying mechanism,Western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1(EGR1)is involved in IGFBP-3 regulation of b FGF and PDGF.IGFBP-3 inhibition of type 1 insulin-like growth factor receptor(IGF1R),ERK and AKT activation is IGF-1-dependent.Furthermore,transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1,b FGF and PDGF expression.CONCLUSION In conclusion,these findings suggest that IGFBP-3suppresses transcription of EGR1 and its target genes b FGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation.It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation,suggesting that IGFBP-3 could be a target for the treatment of HCC.

Insulin-like growth factor-1 induces lymphangiogenesis and facilitates lymphatic metastasis in colorectal cancer

AIM:To investigate the expression of insulin-like growth factor-1(IGF-1)/insulin-like growth factor-1 receptor(IGF-1R)in colorectal cancer(CRC)tissues and to analyze their correlation with lymphangiogenesis and lymphatic metastasis.METHODS:Immunohistochemistry was used to evaluate IGF-1 and IGF-1R expression and lymphatic vessel density(LVD)in 40 CRC specimens.The correlation between IGF-1/IGF-1R and LVD was investigated.Effects of IGF-1 on migration and invasion of CRC cells were examined using transwell chamber assays.A LoVo cell xenograft model was established to further detect the role of IGF-1 in CRC lymphangiogenesis in vivo. RESULTS:Elevated IGF-1 and IGF-1R expression in CRC tissues was correlated with lymph node metastasis(r=0.715 and 0.569,respectively,P<0.05)and tumor TNM stage(r=0.731 and 0.609,P<0.05).A higher LVD was also found in CRC tissues and was correlated with lymphatic metastasis(r=0.405,P<0.05).A positive correlation was found between LVD and IGF-1R expression(r=0.437,P<0.05).Transwell assays revealed that IGF-1 increased the migration and invasion of CRC cells.In vivo mouse studies showed that IGF-1 also increased LVD in LoVo cell xenografts.CONCLUSION:IGF-1/IGF-1R signaling induces tumorassociated lymphangiogenesis and contributes to lymphatic metastasis of CRC.

CT血管造影联合NSE及IGF-1在进展性脑梗死疾病评估中的应用价值

目的:探究CT血管造影联合神经元特异性烯醇化酶(NSE)、胰岛素样生长因子-1(IGF-1)在进展性脑梗死疾病评估中的应用价值。方法:选取2022年5月至2023年5月长征医院收治的110例疑似进展性脑梗死患者,均行CT血管造影检测,并按病情将其中63例进展性脑梗死患者纳入观察组[依据美国国立研究院卒中量表(NIHSS)评分,按神经功能缺损的状况分为轻度19例、中度25例、重度16例],47例非进展性脑梗死患者纳入对照组。分析两组患者的血管狭窄度,NSE、IGF-1水平的变化,分析神经功能缺损不同程度的NSE、IGF-1水平变化,探究CT血管造影与NSE、IGF-1之间的关系,以及CT血管造影、NSE及IGF-1联合检测对进展性脑梗死的评估价值。结果:与对照组比较,观察组患者的血管狭窄度、NSE水平有所上升,IGF-1水平有所降低,差异有统计学意义(t=20.893、24.156、40.209,P<0.05)。与轻度患者相比,中度和重度患者的IGF-1水平降低,NSE水平升高,差异有统计学意义(t中度=4.689、9.103,t重度=18.464、23.672,P<0.05);与中度患者相比,重度患者的NSE水平上升,IGF-1水平下降,差异有统计学意义(t=5.408、8.118,P<0.05)。NSE水平与血管狭窄度呈正相关(r=0.651,P<0.05),而IGF-1水平与其呈负相关(r=-0.617,P<0.05)。血管狭窄度、NSE与进展性脑梗死呈正相关(r=0.672,P<0.05),而IGF-1与其呈负相关(r=-0.629,P<0.05)。CT血管造影受试者工作特征曲线下面积(AUC)为0.688(95%CI:0.594~0.786)、NSE的AUC为0.710(95%CI:0.609~0.811)、IGF-1的AUC为0.676(95%CI:0.578~0.775),3项联合AUC为0.822(95%CI:0.734~0.910),3项联合对进展性脑梗死的评估价值较高。结论:NSE在进展性脑梗死患者体内的水平较高,IGF-1水平较低,且NSE、IGF-1与CT血管造影联合可有助于增强对进展性脑梗死的临床评估,为临床诊疗该病提供有利依据。

Improvement in erectile dysfunction after insulin-like growth factor-1 gene therapy in diabetic rats

Aim： To determine whether adenoviral gene transfer of insulin like growth factor-1 （IGF-1） to the penis of streptozotocin （STZ）-induced diabetic rats could improve erectile capacity. Methods： The STZ diabetic rats were transfected with AdCMV-βgal or AdCMV-IGF-1. These rats underwent cavernous nerve stimulation to assess erectile function and their responses were compared with those of age-matched control rats 1 to 2 days after transfection. In control and transfected STZ diabetic rats, IGF-1 expression were examined by reverse transcription polymerase chain reaction （RT-PCR）, Western blot and histology. The penis β-galactosidase activity and localization of the STZ diabetic rats were also determined. Results： One to two days after transfection, the β-galactosidase was found in the smooth muscle cells of the diabetic rat penis transfected with AdCMV-βgal. One to 2 days after administration of AdCMV- IGF-1, the cavernosal pressure, as determined by the ratio of maximal intracavernous pressure-to-mean arterial pressure （ICP/MAP） and total intracavernous pressure （ICP）, was increased in response to cavernous nerve stimulation. Transgene expression was confirmed by RT-PCR, Western blot and histology. Conclusion： Gene transfer of IGF-1 significantly increased erectile function in the STZ diabetic rats. These results suggest that in vivo gene transfer of IGF- 1 might be a new therapeutic intervention for the treatment of erectile dysfunction （ED） in the STZ diabetic rats.

Effects of Bifidobacterium infantis on cytokine-induced neutrophil chemoattractant and insulin-like growth factor-1 in the ileum of rats with endotoxin injury

BACKGROUND The digestive tract is the maximal immunizing tissue in the body, and mucosal integrity and functional status of the gut is very important to maintain a healthy organism. Severe infection is one of the most common causes of gastrointestinal dysfunction, and the pathogenesis is closely related to endotoxemia and intestinal barrier injury. Bifidobacterium is one of the main probiotics in the human body that is involved in digestion, absorption, metabolism, nutrition, and immunity.Bifidobacterium plays an important role in maintaining the intestinal mucosal barrier integrity. This study investigated the protective mechanism of Bifidobacterium during ileal injury in rats.AIM To investigate the effects of Bifidobacterium on cytokine-induced neutrophil chemoattractant(CINC) and insulin-like growth factor 1(IGF-1) in the ileum of rats with endotoxin injury.METHODS Preweaning rats were randomly divided into three groups: Control(group C),model(group E) and treatment(group T). Group E was intraperitoneally injected with lipopolysaccharide(LPS) to create an animal model of intestinal injury.Group T was intragastrically administered Bifidobacterium suspension 7 d before LPS. Group C was intraperitoneally injected with normal saline. The rats were killed at 2, 6 or 12 h after LPS or physiological saline injection to collect ilealtissue samples. The expression of ileal CINC mRNA was evaluated by reverse transcription-polymerase chain reaction(RT-PCR), and expression of ileal IGF-1 protein and mRNA was detected by immunohistochemistry and RT-PCR,respectively.RESULTS The ileum of rats in Group C did not express CINC mRNA, ileums from Group E expressed high levels, which was then significantly decreased in Group T(F =23.947, P < 0.05). There was no significant difference in CINC mRNA expression at different times(F = 0.665, P > 0.05). There was a high level of IGF-1 brown granules in ileal crypts and epithelial cells in Group C, sparse staining in Group E, and dark, dense brown staining in Group T. There was a significant difference between Groups C and E and Groups E and T(P < 0.05). There was no significant difference in IGF-1 protein expression at different times(F = 1.269, P > 0.05). IGF-1 mRNA expression was significantly different among the three groups(P < 0.05),though not at different times(F = 0.086, P > 0.05).CONCLUSION Expression of CINC mRNA increased in the ileum of preweaning rats with endotoxin injury, and exogenous administration of Bifidobacterium reduced CINC m RNA expression. IGF-1 protein and mRNA expression decreased in the ileum of preweaning rats with endotoxin injury, and exogenous administration of Bifidobacterium prevented the decrease in IGF-1 expression. Bifidobacterium may increase IGF-1 expression and enhance intestinal immune barrier function in rats with endotoxin injury.

Insulin-like growth factor-1 mRNA isoforms and insulinlike growth factor-1 receptor mRNA expression in chronic hepatitis C

AIM: to evaluate the expression of different insulinlike growth factor(IGF)-1 mRNA isoforms and IGF-1 receptor(IGF-1R) mRNA in hepatitis C virus(HCV)-infected livers. METHODS: Thirty-four liver biopsy specimens from chronic hepatitis C(CH-C) patients were obtained before anti-viral therapy. Inflammatory activity(grading) and advancement of fibrosis(staging) were evaluated using a modified point scale of METAVIR. The samples were analyzed using quantitative real-time PCR technique. From fragments of liver biopsies and control liver that were divided and ground in liquid nitrogen, RNA was isolated using RNeasy Fibrous Tissue Mini Kit according to the manufacturer's instruction. Expression levels of IGF-1 mRNA isoforms(IGF-1A, IGF-1B, IGF-1C, P1, and P2) and IGF-1R mRNA were determined through normalization of copy numbers in samples as related to reference genes: glyceraldehyde-3-phosphate dehydrogenase and hydroxymethylbilane synthase. Results on liver expression of the IGF-1 mRNA isoforms and IGF-1R transcript were compared to histological alterations in liver biopsies and with selected clinical data in the patients. Statistical analysis was performed using Statistica PL v. 9 software. RESULTS: The study showed differences in quantitative expression of IGF-1 mRNA variants in HCV-infected livers, as compared to the control. Higher relative expression of total IGF-1 mRNA and of IGF-1 mRNAs isoforms(P1, A, and C) in HCV-infected livers as compared to the control were detected. Within both groups, expression of the IGF-1A mRNA isoform significantly prevailed over expressions of B and C isoforms. Expression of P1 mRNA was higher than that of P2 only in CH-C. Very high positive correlations were detected between reciprocal expressions of IGF-1 mRNA isoforms P1 and P2(r = 0.876). Expression of P1 and P2 mRNA correlated with IGF-1A mRNA(r = 0.891; r = 0.821, respectively), with IGF-1B mRNA(r = 0.854; r = 0.813, respectively), and with IGF-1C mRNA(r = 0.839; r = 0.741, respectively). Expression of IGF-1A mRNA significantly correlated with isoform B and C mRNA(r = 0.956; r = 0.869, respectively), and B with C isoforms(r = 0.868)(P < 0.05 in all cases). Lower expression of IGF-1A and B transcripts was noted in the more advanced liver grading(G2) as compared to G1. Multiple negative correlations were detected between expression of various IGF-1 transcripts and clinical data(e.g., alpha fetoprotein, HCV RNA, steatosis, grading, and staging). Expression of IGF-1R mRNA manifested positive correlation with grading and HCV-RNA. CONCLUSION: Differences in quantitative expression of IGF-1 mRNA isoforms in HCV-infected livers, as compared to the control, suggest that HCV may induce alteration of IGF-1 splicing profile.

A predictive score for retinopathy of prematurity by using clinical risk factors and serum insulin-like growth factor-1 levels

AIM：To detect the impact of insulin-like growth factor-1（IGF-1）and other risk factors for the early prediction of retinopathy of prematurity（ROP）and to establish a scoring system for ROP prediction by using clinical criteria and serum IGF-1 levels.METHODS：The study was conducted with 127 preterm infants.IGF-1 levels in the 1st day of life,1st,2nd,3rd and4th week of life was analyzed.The score was established after logistic regression analysis,considering the impact of each variable on the occurrences of any stage ROP.A validation cohort containing 107 preterm infants was included in the study and the predictive ability of ROP score was calculated.RESULTS：Birth weights（BW）,gestational weeks（GW）and the prevalence of breast milk consumption were lower,respiratory distress syndrome（RDS）,bronchopulmonarydysplasia（BPD）and necrotizing enterocolitis（NEC）were more frequent,the duration of mechanical ventilation and oxygen supplementation was longer in patients with ROP（P〈0.05）.Initial serum IGF-1 levels tended to be lower in newborns who developed ROP.Logistic regression analysis revealed that low BW（〈1250 g）,presence of intraventricular hemorrhage（IVH）and formula feeding increased the risk of ROP.Afterwards,the scoring system was validated on 107 infants.The negative predictive values of a score less than 4 were 84.3%,74.7%and 79.8%while positive predictive values were 76.3%,65.5%and71.6%respectively.CONCLUSION：In addition to BW〈1250 g and IVH,formula consumption was detected as a risk factor for the development of ROP.Breastfeeding is important for prevention of ROP in preterm infants.

Low-temperature 3D-printed collagen/chitosan scaffolds loaded with exosomes derived from neural stem cells pretreated with insulin growth factor-1 enhance neural regeneration after traumatic brain injury

There are various clinical treatments for traumatic brain injury,including surgery,drug therapy,and rehabilitation therapy;howeve r,the therapeutic effects are limited.Scaffolds combined with exosomes represent a promising but challenging method for improving the repair of traumatic brain injury.In this study,we determined the ability of a novel 3D-printed collagen/chitosan scaffold loaded with exosomes derived from neural stem cells pretreated with insulin-like growth factor-1(3D-CC-INEXOS) to improve traumatic brain injury repair and functional recove ry after traumatic brain injury in rats.Composite scaffolds comprising collagen,chitosan,and exosomes derived from neural stem cells pretreated with insulin-like growth fa ctor-1(INEXOS) continuously released exosomes for 2weeks.Transplantation of 3D-CC-INExos scaffolds significantly improved motor and cognitive functions in a rat traumatic brain injury model,as assessed by the Morris water maze test and modified neurological seve rity scores.In addition,immunofluorescence staining and transmission electron microscopy showed that3D-CC-INExos implantation significantly improved the recove ry of damaged nerve tissue in the injured area.In conclusion,this study suggests that transplanted3D-CC-INExos scaffolds might provide a potential strategy for the treatment of traumatic brain injury and lay a solid foundation for clinical translation.

Electroacupuncture-attenuated ischemic brain injury increases insulin-like growth factor-1 expression in a rat model of focal cerebral ischemia

Acupuncture has recently gained popularity in many countries as an alternative and complementary therapeutic intervention. Previous studies have shown that changes in genes, proteins, and their metabolites were measureable during acupuncture for treatment of cerebral ischemia. Through the use of in situ hybridization and immunohistochemistry, the present study confirmed that electroacupuncture increased insulin-like growth factor-1 mRNA and protein expression in the corpus stfiatum following cerebral ischemia, reduced brain edema following middle cerebral artery occlusion reperfusion, and decreased infarct volume. Results suggested that electroacupuncture is effective in the relief of cerebral ischemia by increasing endogenous insulin-like growth factor-1 expression.

RNA interference affects tumorigenicity and expression of insulin-like growth factor-1,insulin-like growth factor-1 receptor,and basic fibroblast growth factor-2 in rat C6 glioma cells

BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.

Effects of targeted-edited oncogenic insulin-like growth factor-1 receptor with specific-sgRNA on biological behaviors of Hep G2 cells

BACKGROUND Insulin-like growth factor-1 receptor(IGF-1R)is over-expressed in hepatocellular carcinoma(HCC).However,the relationship between IGF-1R activation and HCC progression remains unidentified.AIM To investigate the effects of editing IGF-1R on the biological features of HCC cells.METHODS Immunohistochemistry analyzed the expressions of IGF-1R and P-glyco protein(P-gp)in HCC tissues and their distal non-cancerous tissues(non-Ca).IGF-1R was edited with Crispr/Cas9 system,screened specific sg RNAs,and then transfected into Hep G2 cells.CCK-8,scratch wound test detected cell proliferation,migration,invasion and transwell assays,respectively.Alterations of IGF-1R and P-gp were confirmed by Western blotting.Alterations of anti-cancer drug IC_(50)values were analyzed at the cell level.RESULTS The positive rates of IGF-1R(93.6%,χ~2=63.947)or P-gp(88.2%,χ~2=58.448)were significantly higher(P<0.001)in the HCC group than those(36.6%in IGF-1R or 26.9%in P-gp)in the non-Ca group.They were positively correlated between high IGF-1R and P-gp expression,and they were associated with hepatitis B virus infection and vascular invasion of HCC.Abnormal expressions of circulating IGF-1R and P-gp were confirmed and associated with HCC progression.Biological feature alterations of HCC cells transfected with specific sg RNA showed IGF-1R expression down-regulation,cell proliferation inhibition,cell invasion or migration potential decreasing,and enhancing susceptibility of Hep G2 cells to anti-cancer drugs.CONCLUSION Edited oncogenic IGF-1R was useful to inhibit biological behaviors of Hep G2 cells.

Associations between Placental Insulin-Like Growth Factor-1 Gene Expression, DNA Methylation and Intrauterine Growth Restriction

Intrauterine growth restriction (IUGR) is a common fetal development disorder which has great impact on neonatal health. Insulin-like growth factor-1 (IGF1) has an important role in regulating fetal growth. Whether IGF1 DNA methylation was associated with IUGR has not been studied. Placenta samples from IUGR (n = 27) and normal delivery (n = 29) were collected whereas basic information of mothers and infants were also collected. RT-PCR was performed to examine IGF1 transcriptions and bisulfite sequencing PCR was used for DNA methylation analysis. Gene expression analysis found IUGR had significantly lower IGF1 transcription compared to control group (IUGR: 0.330 ± 0.351;control group: 1.001 ± 0.800, t = 3.995, P IGF1 were all highly methylated and there is no difference on DNA methylation rate between IUGR and control group (IUGR: 75%;control group: 81%;P = 0.09). Interestingly, in both IUGR and control groups, male fetus had significantly higher methylation rate than female fetus (IUGR: male: 87%;female: 74%, P = 0.016;control: male: 82%;female: 69%, P = 0.012). There was no correlation between IGF1gene expression and DNA methylation rate (r = 0.095, P = 0.063). Intrauterine fetal growth restriction placenta had significantly lower IGF1gene expression;however, IGF1 DNA methylation level was similar. A potential fetus gender difference was also found in IGF1 DNA methylation rate.

Expression of insulin-like growth factor-1 mRNA and protein level of corpora striata in ischemic side at the early stage of middle cerebral artery ischemia/reperfusion in rhesus monkeys

BACKGROUND： Insulin-like growth factor-I（IGF-1）, as one of the important members of growth factor family, participants in the regulation of many physiological functions and behaviors, having very strong neuroprotective effect. However, the expression of IGF-1 following cerebral ischemia/reperfusion is still disputed. OBJECTIVE： To observe the expression of IGF-1 and protein of corpora striata in ischemic side at the early stage of middle cerebral artery ischemia/reperfusion in rhesus monkey. DESIGN ： A completely randomized grouping design, controlled animal experiment SETTING ： Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University MATERIALS： ① Totally 17 rhesus monkeys , of either gender, aged 4 to 5 years, were enrolled . Seven rhesus monkeys observed with gene chip were randomly divided into 2 groups： sham operation group （n=3） and ischemia/reperfusion group 〈n=4〉. Ten rhesus monkeys observed with in situ hybridization and immunohistochemistry method were randomly divided into 2 groups： sham operation group 〈n=3 〉and ischemia/reperfusion group （n=7）. Rhesus monkeys observed under microscope were divided into 2 groups： sham operation group （n=6） and ischamia/reperfusion group （n=-11）.②Materials used in the experiment： cresyl violet （Sigma Company, America）; immunohistochemical reagent kit （ Huamei Bio-engineering Company）; In situ hybridization reagent kit （Boshide Bio-engineering Co.Ltd, Wuhan）; 12 800 dots chip （Boxing Company, Shanghai）. METHODS ： This experiment was carried out at the Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University from January 2001 to December 2003.① The onset area of middle cerebral artery was blocked for 2 hours, middle cerebral artery ischemia/reperfusion models were created.② After ischemia/reperfusion for 24 hours, cerebral tissue sections of rhesus monkeys were prepared and stained with cresyl violet. Image analysis was performed with 5001W image analysis software. Morphological change of corpora striata of operative side was observed in the rhesus monkeys between two groups. Total RNA was extracted from cerebral tissue. ③ Detection of gene chip： Cy3-duTP and Cy5-duTP were used to respectively perform reverse transcription labeling. The sample was reversely transcribed into cDNA, then hybridized with cDNA of cerebral tissue. Genes with the separate absolute value of cy3 and cy5〉800, cY3/cy5 〉 2（high expression） or 〈 0.5 （low expression） were found out. Those were genes with differential expression. ④ The expressions of IGF-1 mRNA and protein level of corpora striata in ischemic side of rhe- sus monkeys were detected between sham operation group and ischemia/reperfusion group at 9 and 24 hours after ischemia/reperfusion with in situ hybridization method and immunohistochemical method. Brown granules were IGF-1 protein positive cells. ⑤ Analysis of variance was used in the difference comparison of measurement data among groups. MAIN OUTCOME MEASURES ： ① Change of morphological structure of corpora striata at ischemic side in rhesus monkeys. ② Change of cerebral gene expression profiles at ischemia/reperfusion in rhesus monkeys between two groups.③ Expression of IGF-1 mRNA and protein level of corpora striata at ischemia/reperfu- sion in rhesus monkeys between two groups. RESULTS ： ① Pathological change ： Obvious pathological change of cerebral infarction appeared in the ischemia and reperfusion group, while there was no such pathological change in the sham operation group.② Change of gene expression profile ： There were 4480 genes with difference expression in the ischemia/reperfusion group and sham-operation group, in which, 260 genes had high expression and their absolute value was over 800, and 63 genes had low expression, cy3/cy5 of IGF-1 was 0.379, being relative low ex- pression. ③ IGF-1 mRNA and protein positive cell counts in corpora striata at cerebral ischemic side[IGF-1 mRNA： 〈9.72±1.18）,（9.11 ±0.76）,（14.77±0.60） counts/field：lGF-1 protein： （15.11 ±1.83）,（15.39±0.78）, （34.62±0.97）counts/field, P 〈 0.05-0.01]. CONCLUSION： IGF-1 mRNA and protein are lowly expressed in middle cerebral artery of rhesus monkeys at ischemia/reperfusion.

MELD score,insulin-like growth factor 1 and cytokines on bone density in end-stage liver disease

AIM:To determine the contributions of insulin-like growth factor 1 (IGF-1),cytokines and liver disease severity to bone mineral density in patients pre-transplantation.METHODS:Serum IGF-1,tumor necrosis factor-α (TNFα) and interleukin 6 (IL-6) were measured and the Model for End-Stage Liver Disease (MELD) score calculated in 121 adult patients referred to a single centre for liver transplantation.Bone mineral density (BMD) of the lumbar spine and femoral neck were assessed via dual energy X-ray absorptiometry.Demographics,liver disease etiology,medication use and relevant biochemistry were recorded.RESULTS:A total of 117 subjects were included,with low BMD seen in 68.6%,irrespective of disease etiol-ogy.In multivariable analysis,low body mass index (BMI),increased bone turnover and low IGF-1 were independent predictors of low spinal bone density.At the hip,BMI,IGF-1 and vitamin D status were predictive.Despite prevalent elevations of TNFα and IL-6,levels did not correlate with degree of bone loss.The MELD score failed to predict low BMD in this pre-transplant population.CONCLUSION:Osteopenia/osteoporosis is common in advanced liver disease.Low serum IGF-1 is weakly predictive but serum cytokine and MELD score fail to predict the severity of bone disease.