OBJECTIVEIntrauterine growth retardation (IUGR) may contribute to the disorder of development of fetal brains. L-arginine has been known to be effective in blood vessel distension and improving the blood circulation of placentas. Recent studies have shown that L-arginine can ameliorate the placental hypoxia and improve the development of fetus. This study aimed to explore the effects of L-arginine on the expression of insulin-like growth factor (IGF)-I, IGF-II, IGF binding protein-3(IGFBP3)and IGF-I mRNA in brains of IUGR rats and the possible mechanisms of L-arginine.

METHODSThirty-six pregnant rats were randomly assigned into four groups: Control, Model, Low dose L-arginine (100 mg/kg) and High-dose L-arginine (200 mg/kg L-arginine) groups (n=9 each). IUGR was induced by passive smoking in rats from the last three groups. L-arginine was administered for the last two groups between days 8 and 20 of gestation. On day 21 of gestation, the pup rats were delivered by cesarean section. The levels of IGF-I, IGF-II and IGFBP3 in the brains of pup rats were measured by enzyme-linked immunoadsordent assay (ELISA) and the expression of IGF-I mRNA was detected by fluorescence quantitative PCR (FQ-PCR).

RESULTSThe levels of IGF-I, IGF-II and IGF-I mRNA expression in the Model group were significantly lower than in the Control group, with the IGF-I levels of 0.789 +/- 0.062 ng/mg vs 0.947 +/- 0.042 ng/mg, the IGF-II levels of 0.270 +/- 0.020 ng/mg vs 0.374 +/- 0.015 ng/mg and the IGF-I mRNA expression of (13.12 +/- 1.39) x 10(4) cps/mug RNA vs (21.28 +/- 3.54) x 10(4) cps/mug RNA (P < 0.01). In contrast, the IGFBP3 levels in the Model group were significantly higher than in the Control group (0.253 +/- 0.011 ng/mg vs 0.089 +/- 0.015 ng/mg; P < 0.01). Low or high dose L-arginine treatment increased significantly the IGF-I levels from 0.789 +/- 0.062 ng/mg (Model group) to 0.937 +/- 0.067 ng/mg (low dose group) or 0.858 +/- 0.077 ng/mg (high dose group), the IGF-II levels from 0.270 +/- 0.020 ng/mg (Model group) to 0.318 +/- 0.018 ng/mg (low dose group) or 0.354 +/- 0.021 ng/mg (high dose group) and the IGF-I mRNA expression from (13.12 +/- 1.39) x 10(4) cps/mug RNA (Model group) to (19.24 +/- 2.48) x 10(4) cps/mug RNA (low dose group) or (17.35 +/- 2.30) x 10(4) cps/mug RNA (high dose group) (P < 0.01). The IGFBP3 levels were significantly reduced after low or high dose L-arginine treatment (0.132 +/- 0.006 ng/mg or 0.146 +/- 0.009 ng/mg) compared with those of the Model group (0.253 +/- 0.011 ng/mg) ( P < 0.01).

CONCLUSIONSL-arginine can increase the levels of IGF-I and IGF-II and the IGF-I mRNA expression, and decrease the IGFBP3 level in the brain of rats with IUGR induced by passive smoking, thereby offering protective effects against IUGR.

Animals ; Arginine ; pharmacology ; therapeutic use ; Female ; Fetal Growth Retardation ; metabolism ; prevention & control ; Insulin-Like Growth Factor Binding Protein 3 ; analysis ; Insulin-Like Growth Factor I ; analysis ; genetics ; Insulin-Like Growth Factor II ; analysis ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar

Animals ; Hypoxia ; metabolism ; physiopathology ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Male ; Muscle, Skeletal ; metabolism ; Myostatin ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the expression of IGF-1 and IGFBP-3 in nonalcoholic fatty steatosis hepatocyte models induced by oleic acid.

METHODNonalcoholic fatty steatosis hepatocyte models induced by oleic acid on immortalized human hepatocyte, Oil red O staining and intracellular triglycerides were detected for observing the situation of IHH cells fatty degeneration. IHH cells were divided into control group, NAFLD group, which the control group cultured in DMEM/F12 medium, NAFLD group were treated with oleic acid, 0.5 mmol/L treatment for 72 h. The expression of mRNA and protein of IGF-1 and IGFBP3 were measured by immunofluorescent staining, Western blot and RT-PCR methods. Between the two groups were compared using the t- test.

RESULTSThe steatosis models of the hepatocytes were established successfully with 0.5 mmol/L oleic acid. Lipid droplets were observed through Oil red O staining. The level of hepatocyte TG was increased (275.7+/-27.2) mug/mg from (150.2+/-15.6) mug/mg (t = 21.67, P less than 0.01). Compared with the control group, the mRNA of IGF-1 (0.76+/-0.04 vs 4.82+/-1.51, t = 17.915, P less than 0.01), IGFBP-3 (1.58+/-0.93 vs 5.41+/-1.37, t = 12.893, P less than 0.01) and protein expression of IGF-1 (1.00+/-0.29 vs 2.56+/-0.71, t = 29.17, P less than 0.01), IGFBP-3 (0.65+/-0.36 vs 1.23+/-0.91, t = 32. 12, P less than 0.01) significantly decreased in oleic acid-treated group. The results of immunofluorescence staining also confirm the significantly decreased protein expression of IGF-1 and IGFBP-3 in NAFLD group compared with control group.

CONCLUSIONThe expression of IGF-1 and IGFBP-3 decreased in nonalcoholic fatty steatosis hepatocyte models, which will provide the experimental basis for the further study of the mechanism of the limited height of some children with non-alcoholic fatty liver disease in clinical.

Cell Line ; Fatty Liver ; metabolism ; pathology ; Hepatocytes ; metabolism ; pathology ; Humans ; Insulin-Like Growth Factor Binding Protein 3 ; genetics ; metabolism ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Non-alcoholic Fatty Liver Disease

To explore the relationship between Insulin-like growth factor (IGF)-I , -II and lung development in neonatal rats. 80 timed pregnant Sprague-Dawley (SD) rats were randomly divided into 4 groups (n=20): group A (Control group), group B (Dexamethasone (DEX) 1 group), group C (DEX 2 group), group D (retinoic acid (RA) group). 20 pregnant rats in group A, B and D were injected subcutaneously or intraperitoneally with vehicle (NS), DEX, or RA respectively during gestational day 16 to 18. All newborn rats in group C were subcutaneously injected with DEX at day 1 to 3 after birth. The lung tissue was obtained at the following times: fetuses at gestational ages of 18, 20 and 21 days, and 1, 3, 5, 7, 10, 14 and 21 days after birth. Lung tissues were used for histopathological study, the polypeptides analysis of IGF- I, -II (immunohistochemistry and Western blot) and mRNA analysis ( RT- PCR). The results showed that the strongest expression of IGF- I in group A and D occurred at ages of 5-7 days (alveolar stage). The stronger their expressions, the better the alveolar develop. The peak stage of expression in group B occurred earlier, on the day 3 after birth. Compared with group A, the expression of IGF-I during gestation age of 18 days to age of 3 days in group B were significantly higher (P<0.01), but significantly lower at other time points (P<0.01). The expression of IGF-I was lower in group C all the time and always higher in group D than those in group A (P<0.01). The peak expression of IGF-II took place at the gestation age of 18 days, then gradually dropped to trace. During 18 days of gestation to age of 3 days, the expression of IGF-II in group B was significantly higher than that in group A (P<0.01). No difference was found among all other groups. The change in the expression of IGF-I, -II mRNA in all 4 groups was similar to that of their polypeptides. The results suggested that there is a close linking between IGF-I , -II and lung development in newborns. The IGF-II works at early stage and the that of IGF- I works at the stage of new septa formation and alveoli maturation. The stronger their expressions, the more mature the lung development.
Animals ; Animals, Newborn ; Dexamethasone ; pharmacology ; Female ; Insulin-Like Growth Factor I ; biosynthesis ; genetics ; Insulin-Like Growth Factor II ; biosynthesis ; genetics ; Lung ; embryology ; growth & development ; metabolism ; Male ; Pregnancy ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tretinoin ; pharmacology

OBJECTIVETo study the effect of cotransfection of genes of insulin-like growth factor I (IGF-I) and herpes simplex virus thymidine kinase (HSV-tk) on wound healing.

METHODSThirty male Wistar rats were inflicted with 30% TBSA full-thickness scald. They were then divided into A group (4.6 microg pcDNA3.1/IGF-I+Lipofectamine 2000+saline), B group (3.6 microg pcDNA3.1/HSV-tk+Lipofectamine 2000+saline), C1 group and C2 group (2.3 microg pcDNA3.1/IGF-I+1.8 microg pcDNA3.1/HSV-tk+Lipofectamine 2000+saline), and D group (3.0 microg pcDNA3.1+Lipofectamine 2000+saline) according to the random number table, with 6 rats in each group. The above-mentioned mixtures were subcutaneously injected into left back of each rat the moment after injury and on post scald day (PSD) 7, 14, 21, and 28. Gancyclovir (2.5 mg/100 g) was hypodermically injected into rats in C2 group on PSD 29, 30, 31, 32. Changes in body weight of rats were measured. Wound healing rates were calculated. On PSD 35, the expressions of IGF-I gene in local wound and liver tissue were determined with immunohistochemical staining. The serum expression of IGF-I was determined with radioimmunoassay. Expression of HSV-tk gene in local wound was determined with RT-PCR. Apoptosis of fibroblast in C1 and C2 groups was observed under transmission electron microscope. Data were processed with one-way analysis of variance and Turkey method.

RESULTSBody weight of rats in A, C1, and C2 groups increased from PSD 7 through 35, and the difference between former three groups and B, D groups was statistically significant (with F value respectively 2.764, 4.519, 5.009, 13.449, 5.877, P values all below 0.05). Wound healing rates of rats in A, C1, and C2 groups were higher than those in B, D groups (with F value respectively 5.286, 100.880, 152.380, 127.850, 147.750, P values all below 0.05). IGF-I gene was positively expressed in wound fibroblast in A, C1 and C2 groups, but negatively in liver tissues of all the rats. There was no significant statistical difference among groups in serum content of IGF-I [from (1185+/-170) to (1270+/-130) ng/mL, F=0.355, P=0.838]. HSV-tk gene was positively expressed in rat skin tissue in B, C1 and C2 groups. Fibroblast apoptosis was observed under transmission electron microscope in C2 group, but it was not observed in C1 group.

CONCLUSIONSCotransfection of pcDNA3.1/IGF-I and pcDNA3.1/HSV-tk mediated by liposome can promote wound healing, and inhibit the scar proliferation to some extent.

Animals ; Burns ; genetics ; metabolism ; therapy ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Male ; Rats ; Rats, Wistar ; Simplexvirus ; enzymology ; Thymidine Kinase ; genetics ; metabolism ; Transfection ; Wound Healing

This study aims to assess the expression of Klotho and insulin-like growth factor-1 (IGF-1) and the association between Klotho and IGF-1 in rats with dementia model. Thirty rats were randomly divided into three groups. Morris water maze was used to investigate the learning and memory functions, and enzyme linked immunosorbent assay was used to analyze the levels of Klotho and IGF-1. Klotho and IGF-1 levels in the model group were lower than those in other 2 groups. Morris water maze test showed that the model group had longer escape latency times and shorter step platform times compared to other groups. Line correlation model demonstrated that Klotho level was positively correlated with IGF-1 level in rats with dementia (P= 0. 029). The levels of Klotho and IGF-1 both reduced at hippocampus in rats with dementia model, suggesting that it may be a close relationship between Klotho and IGF-1 in the pathogenesis of dementia.
Animals ; Dementia ; metabolism ; Female ; Glucuronidase ; genetics ; metabolism ; Hippocampus ; metabolism ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Male ; Maze Learning ; Memory ; physiology ; Rats ; Rats, Wistar

BACKGROUNDCyanotic patients have potential growth retardation and malnutrition due to hypoxemia and other reasons. Ghrelin is a novel endogenous growth hormone secretagogue that has effects on growth and cardiovascular activities. The aim of this study was to evaluate the plasma level and myocardial expression of ghrelin and insulin-like growth factor-1 (IGF-1) using an immature piglet model of chronic cyanotic congenital heart defects with decreased pulmonary blood flow.

METHODSTwelve weanling Chinese piglets underwent procedures of main pulmonary artery-left atrium shunt with pulmonary artery banding or sham operation as control. Four weeks later, hemodynamic parameters were measured. Enzyme-linked immunosorbent assay for plasma ghrelin and IGF-1 level measurement were performed. Ventricular ghrelin and IGF-1 mRNA expressions were measured by quantitative real-time polymerase chain reaction.

RESULTSFour weeks after surgical procedure, the cyanotic model produced lower arterial oxygen tension ((68.73 ± 15.09) mmHg), arterial oxygen saturation ((82.35 ± 8.63)%), and higher arterial carbon dioxide tension ((51.83 ± 6.12) mmHg), hematocrit ((42.67 ± 3.83)%) and hemoglobin concentration ((138.17 ± 16.73) g/L) than the control piglets ((194.08 ± 98.79) mmHg, (96.43 ± 7.91)%, (36.9 ± 4.73) mmHg, (31.17 ± 3.71)%, (109.83 ± 13.75) g/L) (all P < 0.05). Plasma ghrelin level was significantly higher in the cyanotic model group in comparison to the control (P = 0.004), and the plasma IGF-1 level was significantly lower than control (P = 0.030). Compared with control animals, the expression of ghrelin mRNAs in the ventricular myocardium was significantly decreased in the cyanotic model group (P = 0.000), and the expression of IGF-1 mRNAs was elevated (P = 0.001).

CONCLUSIONSChronic cyanotic congenital heart defects model was successfully established. Plasma ghrelin level and myocardial IGF-1 mRNA expression were significantly up-regulated, while plasma IGF-1 level and myocardial ghrelin mRNA expression were down-regulated in the chronic cyanotic immature piglets. The ghrelin system may be an important part of the network regulating cardiac performance.

Animals ; Cyanosis ; blood ; metabolism ; physiopathology ; Female ; Ghrelin ; blood ; metabolism ; Heart Defects, Congenital ; blood ; metabolism ; physiopathology ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Male ; Pulmonary Circulation ; physiology ; Swine

OBJECTIVETo establish the bone marrow stem cells (MSC) model which could highly express the insulin-like growth factor 1 (IGF-1) transfected by dog's IGF-1 gene.

METHODSpIRES2-EGFP-IGF-1 was transfected into MSC by lipofectamine. Positive clones were selected with G418. The expression of IGF-1 protein in the MSC was determined by immunohistochemistry and Western blot analysis. The IGF-1 in the supernatant of the transfected MSC was detected by sandwich-in ELISA. The periodontal ligament cells (PDLC) were cultured in the supernatant of the transfected MSC. The changes of PDLC' proliferation were observed by MTT.

RESULTSIGF-1-transfected MSC could apparently express IGF-1. The IGF-1 protein in the supernatant of the transfected MSC was confirmed by sandwich-in ELISA. IGF-1 could promote the PDLC' proliferation.

CONCLUSIONSThe MSC transfected by dog's IGF-1 gene can highly express IGF-1, which may lay the foundation for further study on periodontal regeneration.

Animals ; Bone Marrow Cells ; cytology ; metabolism ; Cells, Cultured ; Dogs ; Genetic Vectors ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Male ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Transfection

OBJECTIVETo explore the correlation between methylation of insulin-like growth factor 1 (IGF-1) gene promoter and its placenta-specific expression and fetal macrosoma.

METHODSOne hundred twenty nine healthy pregnant women were recruited between April 2011 and March 2012. Baseline data were collected with self-report questionnaires. Real-time quantitative PCR was used to determine the expression of IGF-1 mRNA in the placenta. Methylation level of the IGF 1 gene was determined with matrix-assisted laser desorption/ionization-time of flight mass spectrometry.

RESULTSThe expression of IGF-1 in placenta and its methylation level showed no significant difference between macrosomic fetuses and controls. No linear correlation was found between IGF-1 mRNA expression and methylation level of IGF-1 promoter (r=0.128, P=0.295). IGF-1 promoter region in placenta showed a hypomethylation status. However, a positive correlation was found between IGF-1 expression and birth weight below 4260 g (r=0.264, P=0.022). The expression of IGF-1 mRNA was significantly higher in those with a birth weight below 4260 g, which suggested that placental IGF-1 expression may contribute to increased birth weight. In regard to fetal overgrowth, however, there seemed to be a negative correlation in which placental IGF-1 expression was downregulated to limit fetal overgrowth.

CONCLUSIONNo linear correlation was found between placental IGF-1 expression and methylation level of IGF-1 promoter with a hypomethylation status. The contribution of placental IGF-1 expression to birth weight is bidirectional. Increased expression seems to promote fetal growth, while decreased expressions may curb overgrowth, therefore control fetal growth in a relatively normal range.

Birth Weight ; DNA Methylation ; Female ; Fetal Macrosomia ; genetics ; Humans ; Infant, Newborn ; Insulin-Like Growth Factor I ; genetics ; Placenta ; metabolism ; Pregnancy ; Promoter Regions, Genetic ; RNA, Messenger ; analysis

In the study of the relationship between cells overloading and the formation, regeneration and growth of bone, the text discussed osteoblasts express IGF-1 variation under overloading environment. The research of overloading on cellular level may elucidate the mechanical effect on the formation, regeneration and growth of bone and the mechanism of cell response in bone.
Animals ; Humans ; Insulin-Like Growth Factor I ; biosynthesis ; genetics ; Osteoblasts ; cytology ; metabolism ; Osteogenesis ; RNA, Messenger ; biosynthesis ; genetics ; Stress, Mechanical ; Weight-Bearing ; physiology