Effect of electroacupuncture on liver Akt/FoxO1 signaling pathway in rats with diabetic fatty / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) on liver protein kinase B (Akt)/forkhead box transcription factor 1 (FoxO1) signaling pathway in Zucker diabetic fatty (ZDF) rats, and to explore the possible mechanism of EA on improving liver insulin resistance of type 2 diabetes mellitus.@*METHODS@#Twelve male 2-month-old ZDF rats were fed with high-fat diet for 4 weeks to establish diabetes model. After modeling, the rats were randomly divided into a model group and an EA group, with 6 rats in each group. In addition, six male Zucker lean (ZL) rats were used as the blank group. The rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36), "Sanyinjiao" (SP 6), "Weiwanxiashu" (EX-B 3), and "Pishu" (BL 20). The ipsilateral "Zusanli" (ST 36) and "Weiwanxiashu" (EX-B 3) were connected to EA device, continuous wave, frequency of 15 Hz, 20 min each time, once a day, six times a week, for a total of 4 weeks. The fasting blood glucose (FBG) in each group was compared before modeling, before intervention and after intervention; the serum levels of insulin (INS) and C-peptide were measured by radioimmunoassay method, and the insulin resistance index (HOMA-IR) was calculated; HE staining method was used to observe the liver tissue morphology; Western blot method was used to detect the protein expression of Akt, FoxO1 and phosphoenolpyruvate carboxykinase (PEPCK) in the liver.@*RESULTS@#Before intervention, compared with the blank group, FBG was increased in the model group and the EA group (P<0.01); after intervention, compared with the model group, FBG in the EA group was decreased (P<0.01). Compared with the blank group, the serum levels of INS and C-peptide, HOMA-IR, and the protein expression of hepatic FoxO1 and PEPCK were increased (P<0.01), while the protein expression of hepatic Akt was decreased (P<0.01) in the model group. Compared with the model group, the serum levels of INS and C-peptide, HOMA-IR, and the protein expression of hepatic FoxO1 and PEPCK were decreased (P<0.01), while the protein expression of hepatic Akt was increased (P<0.01) in the EA group. In the model group, the hepatocytes were structurally disordered and randomly arranged, with a large number of lipid vacuoles in the cytoplasm. In the EA group, the morphology of hepatocytes tended to be normal and lipid vacuoles were decreased.@*CONCLUSION@#EA could reduce FBG and HOMA-IR in ZDF rats, improve liver insulin resistance, which may be related to regulating Akt/FoxO1 signaling pathway.

Marcadores de selección en cerdos Pampa Rocha: comparación con razas autóctonas de España y Portugal / Selection markers in Pampa Rocha piqs: a comparison with autochthonous breeds of Spain and Portugal

RESUMEN Objetivo. El análisis de marcadores de selección permite obtener datos de la vida evolutiva de una raza o línea y permite también evaluar la conveniencia o no de su uso en programas de mejora genética. Hemos evaluado SNPs en cuatro genes (IGF2, MC4R, PRKAG3 y PEPCK-C), que tienen importantes efectos fenotípicos, en cerdos de la raza Pampa Rocha, una raza criolla, y hemos comparado sus frecuencias alélicas con cerdos de diversas razas autóctonas y líneas de España y Portugal no sometidas a selección así como con jabalíes y cerdos de la raza Piétrain. Materiales y métodos. Los SNPs fueron analizados mediante diversas técnicas de RT-PCR. Resultados. Los resultados de los análisis muestran una similitud de frecuencias alélicas entre los cerdos de la raza Pampa Rocha y los cerdos autóctonos de la península ibérica sobre todo en el gen IGF2 y, en menor medida en el gen PEPCK-C. Sin embargo difieren considerablemente en el caso del marcador MC4R y, también en menor medida, en PRKAG3. En el trabajo se discute el uso potencial de los resultados obtenidos para orientar la selección genética de cerdos de la raza Pampa Rocha. Conclusiones. Nuestros resultados demuestran la peculiaridad de la raza Pampa Rocha con respecto a los marcadores estudiados.

ABSTRACT Objective. The analysis of selection markers allows to obtain information about the evolutive story of a particular breed or line and allows also to evaluate the usefulness of those markers for breeding programs. We have analyzed SNPs in four genes of the creole pig breed Pampa Rocha and we have compared their allelic frequencies with the allelic frequencies of diverse autochthonous breeds of Spain and Portugal and also with Piétrain pigs and wild boars. Materials and methods. The SNPs were analyzed using diverse RT-PCR methods. Results. The results of the analysis show that Pampa Rocha pigs have similar allelic frequencies with the autochthonous breeds of Spain and Portugal especially in the case of IGF2 and also, but not so coincident, in the case of PEPCK-C. However, they differ considerably for MC4R, and also, but in a lower extent, for PRKAG3. We discuss in this work the usefulness of our results for breeding of Pampa Rocha pigs. Conclusions. Our results demonstrate the peculiarity of the Pampa Rocha breed regarding the markers studied.

D-Xylose as a sugar complement regulates blood glucose levels by suppressing phosphoenolpyruvate carboxylase (PEPCK) in streptozotocin-nicotinamide-induced diabetic rats and by enhancing glucose uptake in vitro

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. D-Xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of D-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with D-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with D-xylose. These groups were maintained for two weeks. The effects of D-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic beta-cells were analyzed. RESULTS: In vivo, D-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. D-Xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of D-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with D-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, D-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, D-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by beta-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.

Effect of Roux-en-Y gastric bypass postoperative on the blood glucose expression of type 2 diabetic rats / 局解手术学杂志

Objective Recent studies have found that Roux-en-Y gastric bypass( RYGB) can inhibit the levels of blood glucose in type 2 diabetes,but its mechanism still remains unknown. In present study,we observed the effect of RYGB on insulin and GLP-1of type 2 diabetes mice. Methods The 12-week-old male SD rats were divided into four groups:group A ( no surgery,normal diet) ,Group B ( no surgery,DM diet+STZ injection) ,group C ( gastric bypass surgery+normal diet) ,group D ( gastric bypass surgery+DM diet+STZ injection) . One week after surgery rehabilitation,the diabetes model was built by STZ ( revulsant of the classical diabetes model) and high-fat-control diet. After four months,the changes of blood glucose,OGTT,body weight,food intake,water intake in each group were examined. Furthermore,the patho-logical changes of insulin and pancreatic were detected by HE staining. Meanwhile,the liver PEPCK gene and protein expression were detec-ted by using RT-PCR and Western blot. Results Four groups of rats all have significant changes in diet and weight. HE staining suggests the disseminated hyperemia and edema in pancreas and showed that islet has been severe damaged. Compared with no treatment normal diet,nor-mal rat+DM diet+STZ injection,has a markedly elevated blood glucose level 3 days later,insulin,OGTT,GLP,and ITT all have remarkable changes in different time periods,with a statistically significance (P<0. 05). Compared with the normal rat+DM diet+STZ injection group, RYGB + DM diet+ STZ injection group showed that these indicators of pancreas pathological changes significantly,glucose,insulin,OGTT, GLP,ITT all have significantly drop,as well as the gene and protein expression of PEPCK (P<0. 05). Conclusion RYGB can exert influ-ence on the change of insulin,OGTT,GLP,ITT and PEPCK in islets of type 2 diabetes rats,which may play a positive role in the further clini-cal applications.

Upregulated hepatic expression of mitochondrial PEPCK triggers initial gluconeogenic reactions in the HCV-3 patients

Objective:To identify the differential expression of candidate gluconeogenic genes which may initiate hepatitis C virus (HCV) related metabolic disorder during early stages of disease. Methods:Patients of diverse age and sex, with positive HCV genotype 3 (HCV-3) RNA in serum and with no history of other related infections, co-infections, alcoholism, diabetes or chemotherapeutic treatments were considered for this study. Semi-quantitative reverse transcriptase PCR analysis and quantitative fold change analysis of the fresh liver biopsies of eight chronically infected HCV-3 patients and six healthy individuals were evaluated for three potential biomarkers involved in glucose homeostasis induction, namely mitochondrial phosphoenolpyruvate carboxykinase 2 (PCK2), glucose-6-phosphatase catalytic subunit (G6PC) and associated forkhead box protein 01 (FOXO1).Results:Symptomatic evaluation, clinical history and blood test were conducted according to general disease prognosis procedures and reported here. Significantly upregulated expression ofPCK2 independent of age, sex and viral infectivity levels in all HCV patients was observed, whereas no significant changes in the expression ofG6PC andFOXO1were found.Conclusions:PCK2 triggers initial gluconeogenic reactions which ultimately result in the accumulation of glycogen in the liver hepatocytes. We therefore suggest that the overproduction of PCK2 has important physiological role in the onset of metabolic disorder in the HCV-3 patients.

Upregulated hepatic expression of mitochondrial PEPCK triggers initial gluconeogenic reactions in the HCV-3 patients

Objective: To identify the differential expression of candidate gluconeogenic genes which may initiate hepatitis C virus (HCV) related metabolic disorder during early stages of disease. Methods: Patients of diverse age and sex, with positive HCV genotype 3 (HCV-3) RNA in serum and with no history of other related infections, co-infections, alcoholism, diabetes or chemotherapeutic treatments were considered for this study. Semi-quantitative reverse transcriptase PCR analysis and quantitative fold change analysis of the fresh liver biopsies of eight chronically infected HCV-3 patients and six healthy individuals were evaluated for three potential biomarkers involved in glucose homeostasis induction, namely mitochondrial phosphoenolpyruvate carboxykinase 2 (PCK2), glucose-6-phosphatase catalytic subunit (G6PC) and associated forkhead box protein 01 (FOXO1). Results: Symptomatic evaluation, clinical history and blood test were conducted according to general disease prognosis procedures and reported here. Significantly upregulated expression of PCK2 independent of age, sex and viral infectivity levels in all HCV patients was observed, whereas no significant changes in the expression of G6PC and FOXO1 were found. Conclusions: PCK2 triggers initial gluconeogenic reactions which ultimately result in the accumulation of glycogen in the liver hepatocytes. We therefore suggest that the overproduction of PCK2 has important physiological role in the onset of metabolic disorder in the HCV-3 patients.

Upregulated hepatic expression of mitochondrial PEPCK triggers initial gluconeogenic reactions in the HCV-3 patients

OBJECTIVE@#To identify the differential expression of candidate gluconeogenic genes which may initiate hepatitis C virus (HCV) related metabolic disorder during early stages of disease.@*METHODS@#Patients of diverse age and sex, with positive HCV genotype 3 (HCV-3) RNA in serum and with no history of other related infections, co-infections, alcoholism, diabetes or chemotherapeutic treatments were considered for this study. Semi-quantitative reverse transcriptase PCR analysis and quantitative fold change analysis of the fresh liver biopsies of eight chronically infected HCV-3 patients and six healthy individuals were evaluated for three potential biomarkers involved in glucose homeostasis induction, namely mitochondrial phosphoenolpyruvate carboxykinase 2 (PCK2), glucose-6-phosphatase catalytic subunit (G6PC) and associated forkhead box protein 01 (FOXO1).@*RESULTS@#Symptomatic evaluation, clinical history and blood test were conducted according to general disease prognosis procedures and reported here. Significantly upregulated expression of PCK2 independent of age, sex and viral infectivity levels in all HCV patients was observed, whereas no significant changes in the expression of G6PC and FOXO1 were found.@*CONCLUSIONS@#PCK2 triggers initial gluconeogenic reactions which ultimately result in the accumulation of glycogen in the liver hepatocytes. We therefore suggest that the overproduction of PCK2 has important physiological role in the onset of metabolic disorder in the HCV-3 patients.

Establishment of chromatin immunoprecipitation assay to analyze transcriptional regulation of gene expression / 中华检验医学杂志

Objective To establish a Chromatin immunoprecipitation assay to analyze transcriptional regulation of gene expression in hepatocytes. Methods The PEPCK gene was used as a target gene, HPRT, MBP and IgG were used as internal reference, the chromatin immunoprecipitation and PCR were performed with antibody specific for CREB to verify bindings of transcription factor CREB to the PEPCK promoter under various metabolic conditions. Results Transcription factor CREB occupies its target sites in the PEPCK promoter and this binding is increased by 4-fold during fasting in the anti-CREB antibody immunoprecipitated DNA fragments. Conclusion The results confirm that CREB binds to the PEPCK promoter and is involved in transcriptional regulation of PEPCK gene in hepatocytes.