جستجوی مقالات مرتبط با کلیدواژه « IGF » در نشریات گروه « پزشکی »

Polycystic ovarian syndrome (PCOS) often induces reduced ovulation, infertility and insulin resistance. One of the most influential inducer factors in disease is peroxisome proliferator-activated receptor gamma (PPARγ) a member of the nuclear receptor superfamily, which has a variety of physiological functions. PPARγ agonists are used for the treatment of insulin resistance, hyperandrogenism and ovarian dysfunction in PCOS patients. Fatty acids like eicosapentaenoic acid (EPA) and their metabolites are natural ligands for PPARγ and a good option for regulation of PPARγ gene expression.
This case-control study was carried out on 30 women with PCOS referred to the Tabriz-Alzahra fertility center for in vitro fertilization (IVF). Granulosa cells collected from follicular fluid of these individuals were cultured in vitro. Gene expression of PPARγ, insulin-like growth factor 1(IGF-1) and cyclooxygenase-2 were examined on cultured granulosa cells in culture medium and EPA–mediated culture media.
The PPARγ gene expression was increased in EPA-treated medium with a maximum expression at a concentration of 100 mmol in 48 hours. On this basis, increment of PPARγ expression lead to the increased gene expression involved in the steroidogenesis, (i.e. IGF-1). However, the exptression of both genes were decreased in PCOS and the control medium.
In this study, we observed that different concentrations of EPA increased PPARγ gene expression.

Low circulating IGF-1 and high hs-CRP may be associated with cardiovascular diseases. Hence, it is an important question that is there any correlation between these important biomarkers? Since the correlation between IGF-1 and hs-CRP has not been adequately investigated, the main aim of this study was to evaluate the association between these biomarkers among postmenopausal women. A total of 361 healthy Iranian postmenopausal women were randomly selected in a population-based study. The metabolic syndrome was defined according to NCEP, ATPIII criteria. Circulating hs-CRP and IGF-1 levels were measured by highly specific enzyme-linked immunosorbent assay method. Women with higher than median hs-CRP levels had lower IGF-1 levels, in comparison to women with lower than median hs-CRP levels (p<0.0001). In multiple regression analysis, after adjustment for age and the metabolic syndrome, IGF-1 levels had a significant inverse correlation with circulating hs-CRP levels (β=-0.139, p<0.007). After adjustment for age, body mass index and type 2 diabetes mellitus, IGF-1 levels also showed an inverse correlation with hs-CRP levels (β=-0.130, p<0.014). There is a significant inverse correlation between serum IGF-1 and hs-CRP levels in postmenopausal women. This finding provides evidence of the potential cardioprotective effect of IGF-1 via anti-inflammatory mechanisms.

The aim of this study was to investigate the response of plasma Myostatin and insulin growth factor like-1 (IGF-1), as two most important proteins that involved in Cachexia syndrome, to acute resistance exercise in healthy elderly people. Twelve healthy older men (Age= 67±1.3 years, BMI= 25±1.4 kg/m2) volunteered for participation in this study. 72hours after the determination of muscular maximal strength (by 1-RM test), subjects participated in acute resistance exercises via 75% 1-RM. In this research, two blood samples were collected at before and immediately after the exercise from Antecubital vein. Plasma Myostatin and serum levels of IGF-1 were measured by ELISA methods. Paired T-Test used for statical analyses of research data. Significant level was set at P≤0.05. The results of this study showed that plasma Myostatin significantly decreased in response to resistance exercise (P=0.0001). Also the serum levels of IGF-1 increased significantly in response to resistance exercise (P=0.0001). In turn, the results reveled that the IGF-1 to Myostatin ratio increased significantly in response to resistance exercise (P=0.001). The results of this study showed that resistance exercise through increases of IGF-1 and decreases of Myostatin causes increment of IGF-1 to Myostatin ratio. According to the results of this study it seems prescription of resistance exercise could positive changes in proteins that involved in Cachexia syndrome in elderly people. Presumably, through this way we can prevent from Cachexia and its many physiological and physical related dysfunctions in theses people. Although more study is needed to clear its mechanisms.

This study investigated the effect of acute resistance exercise on brain-derived neurotrophic factor (BDNF), Insulin-like growth factor-1 (IGF-1) and Insulin-like growth factor binding protein-3 (IGFBP-3) in the elderly. 22 healthy older men participated in this study (mean age of 60-75 years old). 72 hours after the determination of muscular maximal strength (by 1-RM test), subjects participated in acute resistance exercises via 75% 1-RM. Three blood samples were collected at before, immediately and 4hours after the exercise from Antecubital vein. Serum BDNF, IGF-1 and IGFBP-3 measured by ELISA methods. Also, for statistical analyses Pearson correlation test and Repeated Measures (1×3) were used. Significant level was set at P≤0.05. The results showed that, occurs significantly increased in serum BDNF levels, immediately after a session of resistance exercise. But 30 minutes after completion of the protocol, there were no significant changes compared to the serums before the activity (P≤0.05). There was also a significant increase in the amount of IGF-1, after a session of resistance exercise. But 30 minutes after completion of the protocol, there was no significant change compared to the serums before the activity (P≤0.05). In the end, there was no significant change in the levels of IGFBP-3 in immediately and 30 minutes after resistance exercise protocol, compared to the serums before the activity. Summery, the results of this study showed that, in response to resistance exercise, the amount of BDNF and IGF-1 significantly increased, at immediately after the exercise, but there was no significant changes in the levels of IGFBP-3. According to the results of this study, it seems, resistance exercise causes positive changes in the amount of neurotrophic factors which involved in learning and memory. Subsequently, it may causes reduction in the prevalence of neurological disorders associated with learning and memory impairments such as Alzheimers, depression and dementia in elderly.

Background and Delayed wound healing is a common complication of diabetes mellitus. However، less is known about the cause of this pathology. Types of skin cells، extracellular matrix and variety of growth factors are involved in wound healing. The use of recombinant growth factors in researches and production of skin substitutes are still a challenge. Much research has been done on the effects of gene therapy and cell therapy in wound healing. This experimental study assessed the effect of insulin-like growth factor (IGF-1) over expression in combination with fibroblast cells therapy to diabetic wounds in rats. Diabetes was induced in rats using Streptozotocin. Fibroblasts were cultured and transfected with IGF-1. Lipofectamine 2000 was used as reagent transfection and transgene expression levels were measured by ELIZA. To study the in vivo، rats (weighing 170-20 g) were randomly divided into three groups (5/group) and full-thickness wounds were created on the dorsum region. Suspensions of transfected fibroblast and native fibroblast cells were injected into the wound and were compared with the wounds treated with normal saline. For microscopic examination، biopsy was performed on day 8. In in vitro، the maximum expression of IGF-1 in transfected fibroblast cells (96. 95 pg/ml) was 24 h after gene transfer. In vivo، IGF-1 gene therapy increased the number of fibroblast and keratinocyte cells in wound healing process. Granulation tissue formation in transfected fibroblast and native fibroblast cells groups compared with the normal saline group were found to be more organized. The expression of IGF-1 increased by optimization of gene transfer. High concentrations of IGF-1، in combination with cell therapy، had a significant effect on delayed wound healing in diabetic rats.

According to the importance of GH/IGF-I axis and reported effects of physical activity on this axis among healthy children, this study was conducted to determine the effect of a prolonged physical activity program on growth mediators in children with idiopathic short stature (ISS). fourteen pre-pubertal short stature children were randomly allocated to physical activity or control group (7 children in each group). Children in physical activity group performed 8 week physical activity program. Simultaneously, children in control group participated in a drawing course. IGF-I and IGFBP-3 levels in blood were determined after 5 and 8 weeks. Repeated-measure analyses of variance were performed statistical analysis. P<0.05 was considered statistically significant. A significant decrease was observed in IGF-I levels of physical activity group but not in control group after 8 weeks. IGFBP-3 fluctuations were not significant in both groups. Brief endurance-type physical activity program seemed to have resulted in catabolic rather than anabolic responses of the growth axis despite the fact that physical activity led to improved cardiorespiratory responses to physical activity. It is suggested that prolonged physical activity program (>8 weeks) may result in anabolic responses of the GH/IGF-I axis.

High blood levels of IGF-1 in women before menopause، is a risk factor and P53 tumor suppressor gene is also one of the most common genes involved in breast cancer. Since some studies demonstrated that physical activity and compounds found in Celery have anti-cancer effects، this study aimed to investigate the interactive effects of eight weeks massage therapy along with celery seed supplementation on the levels of IGF-1 and P53 in overweight women. In a single، blind، placebo-controlled clinical trial، the interactive effects of eight weeks massage therapy along with celery seed consumption on IGF-1 and P53 serum concentrations in overweight women were measured. For this purpose، 28 overweight women with a BMI of more than 25 kg/m2 in Ghaemshahr were randomly divided into four groups. Weight and serum levels variables of IGF-1 and P53، prior and after the therapy were measured. Then the data were analyzed using t-test and one-way variance analysis. P<0. 05 was considered as the level of significance At the end of the study، the average of weight and level of IGF-1 and P53 in experimental groups (massage therapy، Therapy and supplementation، Supplementation) were decreased. There was a significant difference between the weight (P=0. 003)، the level of IGF-1 (P <0. 001) and P53 (P<0. 001) of women before and after the start of the intervention in the experimental group while the control group was not changed. The results show that massage therapy along with celery seed supplements، especially the combination of these two non-pharmaceutical approaches have beneficial effects on body weight and IGF-1 and P53 levels in overweight women.

IGFs (Insulin-like growth factors) and some binding proteins can cause occurrence and recurrence of breast cancer. Since the role of combined exercise training on these factors is not clear, therefore, the aim of this study was to look at the changes of IGF axis and some binding proteins in postmenopausal women with breast cancer after 15 weeks of combined exercise training. Twenty- nine women with breast cancer (58.27 ± 6.31 years) who underwent surgery, chemotherapy and radiation- therapy with current hormone therapy were divided into two groups of experimental and control. Subjects of the experimental group performed 15 weeks of combined exercises including walking (2 sessions per week) and resistance training (2 sessions per week that differed from walking days). Data were analyzed by using ANCOVA (p≤ 0.05). Combined exercise training had significant effect on IGF-1 levels (P= 0.001), IGFB-3 levels (P= 0.000) and IGF-1: IGFB-3 (P= 0.000) in postmenopausal women with breast cancer. After 15 weeks, IGE -1 reduced in the experimental group up to 9 percent and IGFB-3 increased by 28 percent. On the other hand, exercise training had no significant effect on the IGFB-1 (P= 0.652) in postmenopausal women with breast cancer. While the IGF axis factors and some binding proteins play an important role in breast cancer and its recurrence, it seems that changes in these factors through combined exercise training programs can delay its recurrence.

Abstract Cholinergic neurons play an important role in muscle contraction، in learning and memory. Choline acetyltransferase is the enzyme that is responsible for the synthesis of acetylcholine and is a specific marker for choiinergic neurons. Computational methods investigate on Choline acetyltransferase enzyme. The aim of the present work was to describe and characterize the molecular structure vibrational properties of choline acetyltransferase crystalline-structure. In this work، the structures of a coordination compound modeling the choline acetyltransferase computationally. Thus، it is worthwhile to collect information on their structures by the means of computational chemistry as well. Monte Carlo simulations are based on pair wise additive potentials of the form. In concepts and algorithms of classical MD simulations the atoms of a biopolymer move according to the Newtonian equations of motion. These studies provided insights into the steric، electrostatic، hydrophobic، and hydrogen bonding properties and other structural features influencing the choline acetyltransferasewas Potential energies for the three force fields of MM+، AMBER and OPLS at Monte Carlo simulation were compared. Geometry of optimized variables of Bond length (B)، Bond Angle (A) and Dihedral Angle (D) investigated. The potential energy (kcal/mol) via time (ps) during Molecular Dynamic (MD) simulation at300 K in gas (R2 = 0. 7656) and water (R2 = 0. 9794) environments studied to stabilized structure of choline acetyltransferase accepted. These results also were revealed that the solvation of Choline acetyltransferase molecule is the major component for the interaction potential energy and it was clearly shown that the role of the solute-solvent interactions is more pronounced in Choline acetyltransferase molecule and it’s active site solvation.

Breast cancer is the most common malignancy in women. Many factors such as estrogens، nutrition، etc. play role in the incidence of this cancer. Insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) are the factors recently considered as components of insulin-like growth factor (IGF) system. Studies in this field from 1987 to 2012 by using the databases of NCBI (http: //www. ncbi. nlm. nih. gov/) were analyzed and reviewed 1181 article had examined the effect of IGF-1 in breast cancer. 46 showed a direct association with breast cancer. 92 articles were studied relation of IGF-1 and IGFBP-3 with breast cancer، 9 of them were review articles. Of these، 30 articles were selected as the main references. Studies have shown that IGF-1 gene expression increases in breast cancer. IGF-1 effects in growth، proliferation and tumor genesis is mediated by IGF-1R. IGFBP3 inhibit IGF-1 effects by preventing its binding to a surface receptor (IGF-1R) and interferes with IGF-1 mitoses action. Also، in a mechanism independent on IGF، IGFBP-3 binds to specific membrane proteins and induces apoptosis and inhibits cell growth.