AIM: To characterize the mitochondrial dysfunction in experimental cirrhosis and to study whether insulin-like growth factor-Ⅰ (IGF-Ⅰ ) therapy (4 wk) is able to induce beneficial effects on damaged mitochondri...AIM: To characterize the mitochondrial dysfunction in experimental cirrhosis and to study whether insulin-like growth factor-Ⅰ (IGF-Ⅰ ) therapy (4 wk) is able to induce beneficial effects on damaged mitochondria leading to cellular protection. METHODS: Wistar rats were divided into three groups: Control group, untreated cirrhotic rats and cirrhotic rats treated with IGF-Ⅰ treatment (2 μg/1O0 g bw/d). Mitochondrial function was analyzed by flow cytometry in isolated hepatic mitochondria, caspase 3 activation was assessed by Western blot and apoptosis by TUNEL in the three expedmental groups. RESULTS: Untreated cirrhotic rats showed a mitochondrial dysfunction characterized by a significant reduction of mitochondrial membrane potential (in status 4 and 3); an increase of intramitochondrial reactive oxigen species (ROS) generation and a significant reduction of ATPase activity. IGF-Ⅰ therapy normalized mitochondrial function by increasing the membrane potential and ATPase activity and reducing the intramitochondrial free radical production. Activity of the electron transport complexes Ⅰ and Ⅲ was increased in both cirrhotic groups. In addition, untreated cirrhotic rats showed an increase of caspase 3 activation and apoptosis. IGF- Ⅰ therapy reduced the expression of the active peptide of caspase 3 and resulted in reduced apoptosis. CONCLUSION: These results show that IGF- Ⅰ exerts a mitochondrial protection in experimental cirrhosis leading to reduced apoptosis and increased ATP production.展开更多
Objective:To investigate the relationship between polymorphism within the 5'-untranslated region(5'-UTR)of IGF-I gene and its periparturient concentration in Iranian Holstein dairy cows.Methods:Blood samples(5...Objective:To investigate the relationship between polymorphism within the 5'-untranslated region(5'-UTR)of IGF-I gene and its periparturient concentration in Iranian Holstein dairy cows.Methods:Blood samples(5 mL,n=37)were collected by caudal venipuncture from each animal into sample lubes containing the EDTA and DNA was extracted from blood.In order to measure ICF-I concentration the collection of blood samples(n=111)was also done at 14 d before calving(prepartum),25 and 45 d postpartum.Results:We found evidence for a significant effect of C to T mutation in position 512 of IGF-I gene on its serum concentration in dairy cows in Iran.Cows with CC genotype had significantly higher concentration(Mean-SD)of IGF-I at 14 d prepartum(91.8±18.1)μg/L compared to those with TT genotype(73.3±14.4)μg/L(P=0.04).A significant trend(quadratic)was found for IGF-I concentration,as higher in CC cows compared to ones with TT genotype,during the 14 d before calving to 45 d postpartum(P=0.01).Conclusions:We concluded that C/T transition in the promoter region of IGF-I gene can influence the serum concentration of ICF-I in periparturient dairy cows.展开更多
AIM: To evaluate the effects of ethanol on the insulin- like growth factor-Ⅰ (IGF-Ⅰ) system involved in c-Jun N-terminal kinase (JNK1/2) and alcoholdehydrogenase (ADH) activity in primary cultured rat hepatocytes. M...AIM: To evaluate the effects of ethanol on the insulin- like growth factor-Ⅰ (IGF-Ⅰ) system involved in c-Jun N-terminal kinase (JNK1/2) and alcoholdehydrogenase (ADH) activity in primary cultured rat hepatocytes. METHODS: Hepatocytes isolated from male Sprague-Dawley rats were incubated with various concentrations of ethanol for different durations of time. The cells were pretreated with SP600125 (10 μmol/L) and 4-MP (200 μmol/L), and then treated with ethanol (200 mmol/L). We then measured IGF-Ⅰ secretion, IGF-Ⅰ mRNA expression, cell viability and JNK1/2 activity by radioimmunoassay, RT-PCR, MTT assay and Western blot, respectively (n = 6). RESULTS: Ethanol induced the activity of phospho (p)-JNK1/2, reaching a maximum at 60 min and then decreasing at 180 min. The effects of ethanol on the IGF-Ⅰ system were increased at 60 min (secretion: 7.11 ± 0.59 ng/mg protein vs 4.91 ± 0.51 ng/mg, mRNA expression: 150.2% ± 10.2% vs 101.5% ± 11.3%, P = 0.045) and then decreased at 180 min (secretion: 3.89 ± 0.25 ng/mg vs 5.4 ± 0.54 ng/mg protein; mRNA expression: 41.5% ± 10.4% vs 84.7% ± 12.1%, P = 0.04), however cell viability was decreased in a dose- and time-dependent manner. SP600125 blocked the ethanol-induced changes (at 60 min). Additionally, 4-methylpyrazole prevented the ethanol-induced decreases in the IGF-Ⅰ system, cell viability and p-JNK1/2 activity (at 180 min). CONCLUSION: This study suggests that ethanol- induced p-JNK1/2 activation is associated with the IGF-Ⅰ system and cell viability in hepatocytes. Furthermore, alcohol dehydrogenase is involved in the relationship between ethanol-induced inactivation of p-JNK1/2 and the changes of the IGF-Ⅰ system and cell viability.展开更多
Constitutive activation of the insulin-like growth factor (IGF)-signaling axis is frequently observed in human hepatocellular carcinoma(HCC).Especially the over- expression of the fetal growth factor IGF-Ⅱ,IGF-Ⅰ rec...Constitutive activation of the insulin-like growth factor (IGF)-signaling axis is frequently observed in human hepatocellular carcinoma(HCC).Especially the over- expression of the fetal growth factor IGF-Ⅱ,IGF-Ⅰ receptor(IGF-IR),and cytoplasmic downstream effectors such as insulin-receptor substrates(IRS)contribute to proliferation,anti-apoptosis,and invasive behavior. This review focuses on the relevant alterations in this signaling pathway and independent in vivo models that support the central role IGF-Ⅱsignaling during HCC development and progression.Since this pathway has become the center of interest as a target for potential anti-cancer therapy in many types of malignancies,various experimental strategies have been developed,including neutralizing antibodies and selective receptor kinase inhibitors,with respect to the specific and efficient reduction of oncogenic IGF-Ⅱ/IGF-IR-signaling.展开更多
Objective: We investigated the expression of insulin-like growth factor-1 (IGF-1) so as to explore its relationship with carcinogenesis and development of breast cancer. Methods: IGF-1 mRNA levels in tissues of breast...Objective: We investigated the expression of insulin-like growth factor-1 (IGF-1) so as to explore its relationship with carcinogenesis and development of breast cancer. Methods: IGF-1 mRNA levels in tissues of breast cancer, adjacent breast cancer in 70 cases breast cancer patients were analyzed by RT-PCR with the normal breast tissues of paired breast as the control. Results: The level of IGF-1 mRNA expression in breast cancer tissues was significantly higher than that in the paired adjacent to breast cancer tissues, normal mammary gland tissues. The ration of IGF-1/β-actin were 0.679 ± 0.075, 0.463 ± 0.085, 0.305 ± 0.031, respectively. There was significant difference between different groups (P < 0.005). Expression of IGF-1 was associated with lymph node metastasis, pathological staging and estrogen receptor status of breast cancer and no significant relationship with tumor pathological grouping (P > 0.005). Conclusion: The high-level expression of IGF-1 in breast cancer tissues is correlated with carcinogenesis, development and metastasis of breast cancer.展开更多
基金Supported by The Spanish Program I + D, SAF 2005/08113
文摘AIM: To characterize the mitochondrial dysfunction in experimental cirrhosis and to study whether insulin-like growth factor-Ⅰ (IGF-Ⅰ ) therapy (4 wk) is able to induce beneficial effects on damaged mitochondria leading to cellular protection. METHODS: Wistar rats were divided into three groups: Control group, untreated cirrhotic rats and cirrhotic rats treated with IGF-Ⅰ treatment (2 μg/1O0 g bw/d). Mitochondrial function was analyzed by flow cytometry in isolated hepatic mitochondria, caspase 3 activation was assessed by Western blot and apoptosis by TUNEL in the three expedmental groups. RESULTS: Untreated cirrhotic rats showed a mitochondrial dysfunction characterized by a significant reduction of mitochondrial membrane potential (in status 4 and 3); an increase of intramitochondrial reactive oxigen species (ROS) generation and a significant reduction of ATPase activity. IGF-Ⅰ therapy normalized mitochondrial function by increasing the membrane potential and ATPase activity and reducing the intramitochondrial free radical production. Activity of the electron transport complexes Ⅰ and Ⅲ was increased in both cirrhotic groups. In addition, untreated cirrhotic rats showed an increase of caspase 3 activation and apoptosis. IGF- Ⅰ therapy reduced the expression of the active peptide of caspase 3 and resulted in reduced apoptosis. CONCLUSION: These results show that IGF- Ⅰ exerts a mitochondrial protection in experimental cirrhosis leading to reduced apoptosis and increased ATP production.
基金supported by grant of the School of Veterinary MedicineShiraz University(grant number:87GRVT47)and partly by National Elite Foundation of Iran(number:88GRDIM83440)
文摘Objective:To investigate the relationship between polymorphism within the 5'-untranslated region(5'-UTR)of IGF-I gene and its periparturient concentration in Iranian Holstein dairy cows.Methods:Blood samples(5 mL,n=37)were collected by caudal venipuncture from each animal into sample lubes containing the EDTA and DNA was extracted from blood.In order to measure ICF-I concentration the collection of blood samples(n=111)was also done at 14 d before calving(prepartum),25 and 45 d postpartum.Results:We found evidence for a significant effect of C to T mutation in position 512 of IGF-I gene on its serum concentration in dairy cows in Iran.Cows with CC genotype had significantly higher concentration(Mean-SD)of IGF-I at 14 d prepartum(91.8±18.1)μg/L compared to those with TT genotype(73.3±14.4)μg/L(P=0.04).A significant trend(quadratic)was found for IGF-I concentration,as higher in CC cows compared to ones with TT genotype,during the 14 d before calving to 45 d postpartum(P=0.01).Conclusions:We concluded that C/T transition in the promoter region of IGF-I gene can influence the serum concentration of ICF-I in periparturient dairy cows.
基金Funds of Chonbuk National University and grants of Brain Korea 21 project in 2007
文摘AIM: To evaluate the effects of ethanol on the insulin- like growth factor-Ⅰ (IGF-Ⅰ) system involved in c-Jun N-terminal kinase (JNK1/2) and alcoholdehydrogenase (ADH) activity in primary cultured rat hepatocytes. METHODS: Hepatocytes isolated from male Sprague-Dawley rats were incubated with various concentrations of ethanol for different durations of time. The cells were pretreated with SP600125 (10 μmol/L) and 4-MP (200 μmol/L), and then treated with ethanol (200 mmol/L). We then measured IGF-Ⅰ secretion, IGF-Ⅰ mRNA expression, cell viability and JNK1/2 activity by radioimmunoassay, RT-PCR, MTT assay and Western blot, respectively (n = 6). RESULTS: Ethanol induced the activity of phospho (p)-JNK1/2, reaching a maximum at 60 min and then decreasing at 180 min. The effects of ethanol on the IGF-Ⅰ system were increased at 60 min (secretion: 7.11 ± 0.59 ng/mg protein vs 4.91 ± 0.51 ng/mg, mRNA expression: 150.2% ± 10.2% vs 101.5% ± 11.3%, P = 0.045) and then decreased at 180 min (secretion: 3.89 ± 0.25 ng/mg vs 5.4 ± 0.54 ng/mg protein; mRNA expression: 41.5% ± 10.4% vs 84.7% ± 12.1%, P = 0.04), however cell viability was decreased in a dose- and time-dependent manner. SP600125 blocked the ethanol-induced changes (at 60 min). Additionally, 4-methylpyrazole prevented the ethanol-induced decreases in the IGF-Ⅰ system, cell viability and p-JNK1/2 activity (at 180 min). CONCLUSION: This study suggests that ethanol- induced p-JNK1/2 activation is associated with the IGF-Ⅰ system and cell viability in hepatocytes. Furthermore, alcohol dehydrogenase is involved in the relationship between ethanol-induced inactivation of p-JNK1/2 and the changes of the IGF-Ⅰ system and cell viability.
文摘Constitutive activation of the insulin-like growth factor (IGF)-signaling axis is frequently observed in human hepatocellular carcinoma(HCC).Especially the over- expression of the fetal growth factor IGF-Ⅱ,IGF-Ⅰ receptor(IGF-IR),and cytoplasmic downstream effectors such as insulin-receptor substrates(IRS)contribute to proliferation,anti-apoptosis,and invasive behavior. This review focuses on the relevant alterations in this signaling pathway and independent in vivo models that support the central role IGF-Ⅱsignaling during HCC development and progression.Since this pathway has become the center of interest as a target for potential anti-cancer therapy in many types of malignancies,various experimental strategies have been developed,including neutralizing antibodies and selective receptor kinase inhibitors,with respect to the specific and efficient reduction of oncogenic IGF-Ⅱ/IGF-IR-signaling.
文摘Objective: We investigated the expression of insulin-like growth factor-1 (IGF-1) so as to explore its relationship with carcinogenesis and development of breast cancer. Methods: IGF-1 mRNA levels in tissues of breast cancer, adjacent breast cancer in 70 cases breast cancer patients were analyzed by RT-PCR with the normal breast tissues of paired breast as the control. Results: The level of IGF-1 mRNA expression in breast cancer tissues was significantly higher than that in the paired adjacent to breast cancer tissues, normal mammary gland tissues. The ration of IGF-1/β-actin were 0.679 ± 0.075, 0.463 ± 0.085, 0.305 ± 0.031, respectively. There was significant difference between different groups (P < 0.005). Expression of IGF-1 was associated with lymph node metastasis, pathological staging and estrogen receptor status of breast cancer and no significant relationship with tumor pathological grouping (P > 0.005). Conclusion: The high-level expression of IGF-1 in breast cancer tissues is correlated with carcinogenesis, development and metastasis of breast cancer.