Effect of South African Herb Hoodia gordonii on Liver Glucolipid Metabolism and PI3K/Akt/FoxO1 Signalling Pathway in db/db Mice / 中国实验方剂学杂志

ObjectiveTo observe the effects of the South African herb Hoodia gordonii （HG） on glucolipid metabolism in diabetic db/db mice and explore the possible mechanisms of HG on the liver of db/db mice based on the phosphoinositide-3 kinase （PI3K）/protein kinase B （Akt）/factor forkhead protein O1 （FoxO1） signaling pathway. MethodA total of 30 db/db mice were randomly divided into five groups according to fasting blood glucose： model group， metformin group （0.195 g·kg-1）， and low dose （0.39 g·kg-1）， medium dose （0.78 g·kg-1）， and high dose （1.56 g·kg-1） HG groups， with six m/m mice in each group， and another six m/m mice were set as normal group. The mice in the normal and model groups were given saline of 9 mL·kg-1 by gavage. Body weight， water intake， and fasting blood glucose of the mice in each group were measured weekly. After six weeks of continuous administration， serum insulin （FINS）， low-density lipoprotein cholesterol （LDL）， total cholesterol （TC）， triglyceride （TG）， alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， urea， and creatinine （CREA） were measured， and liver sections were embedded and stained with hematoxylin-eosin （HE）， periodic acid-Schiff （PAS）， and oil red O. Protein expression of PI3K p85， p-Akt， and p-FoxO1 in liver was detected by immunohistochemistry. The mRNA expression of PI3K， Akt， and FoxO1 in liver tissue was detected by real-time polymerase chain reaction （Real-time PCR）. ResultAfter six weeks of administration intervention， it was found that fasting blood glucose was significantly downregulated in mice in the three HG groups （P<0.05）. The level of islet resistance index was significantly reduced in both the low and medium dose HG groups （P<0.05）. The expression levels of TC， TG， and LDL were reduced in all HG groups （P<0.05， P<0.01）. Pathologically， HG could alleviate hepatocyte steatosis， reduce the volume and content of lipid droplets in liver， and increase the distribution of glycogen granules in liver to some extent in mice. Immunohistochemical assays revealed that PI3K p85 protein expression was significantly increased in the low， medium， and high dose HG groups compared with the model group （P<0.01）. p-Akt protein expression was significantly increased in the medium and high dose HG groups （P<0.05， P<0.01）. p-FoxO1 protein expression was significantly increased in the low， medium， and high dose HG groups （P<0.05， P<0.01）. Compared with the model group， PI3K mRNA was increased in low dose， medium dose， and high dose HG groups （P<0.05）， and Akt mRNA was increased in high dose HG group （P<0.05）. FoxO1 mRNA was decreased in low dose， medium dose， and high dose HG groups （P<0.05）. ConclusionHG can ameliorate the disorder of glucolipid metabolism in db/db mice， which may be related to its activation of the hepatic PI3K/Akt/FoxO1 signaling pathway.

Mechanism of Momordica charantia Extract in Regulating Gluconeogenesis in ZDF Diabetes Rats / 中国实验方剂学杂志

ObjectiveTo observe the effect of Momordica charantia extract （MCE） on the gluconeogenesis signaling pathway in diabetes rats. MethodMale Zucker Diabetic Fatty （ZDF） rats aged 5-6 weeks were randomly divided into a model group and an MCE group （administered MCE at a dose of 0.40 g·kg-1 by gavage）. Additionally， seven healthy male ZDF （fa/+） rats were assigned to the normal group and received administration once daily for six consecutive weeks. During the experiment， the general condition of the rats was observed， and body weight was recorded. Fasting blood glucose and random blood glucose levels were measured in the 1st， 3rd， and 5th weeks. In the 6th week， an oral glucose tolerance test （OGTT） was conducted， and serum levels of triglycerides （TG）， free fatty acid （FFA）， total cholesterol （TC）， aspartate aminotransferase （AST）， and alanine aminotransferase （ALT） were measured. Hematoxylin-eosin （HE） staining was performed to examine liver morphology， periodic acid-Schiff （PAS） staining was used to assess hepatic glycogen storage， and Real-time polymerase chain reaction （PCR） was employed to measure the mRNA expression of phosphoenolpyruvate carboxykinase （PEPCK） and glucose-6-phosphatase （G6Pase） in the liver. Western blot analysis was conducted to measure the phosphorylation level of forkhead box protein O1 （FoxO1） and the protein expression of PEPCK and G6Pase in the liver. ResultCompared with the model group， the MCE group showed significant improvements in body weight， fasting blood glucose， random blood glucose， and glucose tolerance （P<0.05， P<0.01） and reduced serum levels of FFA， TC， and TG （P<0.05， P<0.01）. There were no significant differences in ALT and AST between the two groups. In the MCE group， the HE staining revealed more orderly liver cell arrangement and reduced hepatic steatosis and the PAS staining showed increased hepatic glycogen storage. The protein expression of p-FoxO1 in the liver was significantly elevated （P<0.01）， while there was no significant difference in FoxO1 protein expression. The mRNA and protein expression of PEPCK and G6Pase significantly decreased （P<0.05）. ConclusionMCE exhibits glucose-lowering and lipid-lowering effects， improves glucose tolerance， and enhances hepatic glycogen storage. These effects may be attributed to the upregulation of p-FoxO1， leading to the inhibition of PEPCK and G6Pase expression and the regulation of gluconeogenesis-related processes.

Mechanism of Flavonoids from Mulberry Leaves on Insulin Resistance and Inflammatory Response in Diabetic Mice / 中国实验方剂学杂志

ObjectiveTo observe the glucose-lowering， insulin resistance-improving， and anti-inflammatory effects of flavonoids from mulberry leaves （FML） and explore their underlying mechanism. MethodMale db/db mice aged 6-7 weeks were randomly divided into a model group， a high-dose FML group （1.00 g·kg·d-1）， and a low-dose FML group （0.50 g·kg-1·d-1）. C57BL mice of the same age were assigned to the normal group. After six weeks of intervention， fasting blood glucose （FBG）， serum fasting insulin levels （Fins）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， free fatty acid （FFA）， blood creatinine （SCr）， blood urea nitrogen （BUN）， and aspartate aminotransferase （AST） levels were measured， and the homeostasis model assessment of insulin resistance （HOMA-IR） was calculated. Superoxide dismutase （SOD）， glutathione peroxidase （GSH-Px）， and catalase activities in the liver were measured. Morphological changes in the liver were assessed by hematoxylin-eosin （HE） staining. The protein expression of cyclooxygenase-2 （COX-2）， inducible nitric oxide synthase （iNOS）， and nuclear factor-κB （NF-κB） in the liver was detected by Western blot. ResultCompared with the model group， the high-dose and low-dose FML groups showed significant reductions in FBG， Fins， HOMA-IR， IL-6， TNF-α， and FFA levels （P<0.05， P<0.01）， and increased levels of SOD， GSH-Px， and catalase in the liver （P<0.05， P<0.01）. HE staining of the liver in the FML groups showed improved arrangement of hepatocytes， reduced inflammatory cell infiltration， and alleviated cellular steatosis compared with the model group. The protein expression of COX-2， iNOS， and NF-κB in the liver significantly decreased in the FML groups as compared with that in the model group （P<0.05， P<0.01）. ConclusionFML have glucose-lowering and insulin resistance-improving effect， which may be attributed to their regulation of the NF-κB pathway in the liver of diabetic mice， leading to the suppression of the release of COX-2， iNOS， and inflammatory cytokines， thereby improving the inflammatory state.

The Mechanism Behind the Effects of Oleuropein on Insulin Resistance in the Liver in db/db Mice / 世界科学技术-中医药现代化

This study aimed to elucidate the mechanism behind the effects of oleuropein (OL) on improving insulin resistance in obese db/db mice.Twelve 6-to 8-week-old male db/db mice were randomly divided into the model group and the OL group with 6 in each group according to their levels of blood glucose and body weight,while six C57BL/6J mice with the same age were made up for the normal group.Mice of the OL group was intragastrically administered with (50 mg·kg-1) once a day.The mice of the other groups were treated with the saline solution with the same dosage.After treatment for four weeks,OGTT test was carried out,while fast blood glucose and serum insulin were tested.RT-PCT and western blot were used to quantify the mRNA and protein expressions of certain targets in the liver.As a result,it was found that the body weight,fast blood glucose,serum insulin level and insulin resistance index were significantly decreased in the mice of the OL group when compared with model group after the treatment for 4 weeks (P＜0.05 or P＜0.01).Plasma glucose levels at each time point of OGTT tests were lower in the mice of the OL group than those of the model group (P＜0.01).The mRNA and protein expressions of InsR,IRS-1 and GLUT-2 in the mice of the OL group increased significantly (P＜0.01).In conclusion,it was demonstrated that oleuropein may reduce the blood glucose and improve the insulin resistance in db/db mice through up-regulating the mRNA and protein expressions of InsR,IRS-1 and GLUT-2 in the liver.

Effects of Kaempferol on the Skeletal Muscle of KKAy Mice via PI3K-AKT-GLUT4 Signaling / 世界科学技术-中医药现代化

This study aimed to investigate the effects of kaempferol on the skeletal muscle of KKAy mice via PI3K-AKT-GLUT4 signaling.Spontaneous type 2 diabetic KKAy mice were made up for the model group.After 6-week treatment of kaempferol by intragastric administration,key targets of PI3K-AKT-GLUT4 signaling were detected using biochemical and immunohistochemical technique,and western blot.It was found that the body weight,fast blood glucose and random blood glucose were decreased after kaempferol administration.ITT results show that blood glucose at 30 min after injecting insulin and the area under the curve drop were reduced in the kaempferol group,and so was the insulin resistance index in the kaempferol group.In addition,the mRNA expressions of PI3K,AKT and GLUT4 in the kaempferol group increased significantly,while the protein levels of AKT and GLUT4 were up-regulated by kaempferol administration.It was concluded that kaempferol can significantly regulate the blood glucose,body weight and insulin resistance in mice through activating the PI3K-AKT-GLUT4 signaling.

Impacts of Cyclocarya Paliurus Polysaccharide on Insulin Signaling Pathway in H4IIE Liver Cells / 世界科学技术-中医药现代化

This study aimed to explore the impacts of Cyclocarya paliurus polysaccharide (CP) on insulin signal pathway in liver cells.H4IIE liver cells of rat that cultivated for 72 h were made up for the model group.H4IIE cells at 70％-80％ confluence were exposed to various concentrations of CP,including 50,100,200 and 400 μg·mL 1,for measuring cell viability using Neutral Red.Based on the results of cell viability,H4IIE cells were divided into the control group,the insulin group (100 nmol·L-1),the low dose CP group (the LCP group,200 μg· mL-1) and the high dose CP group (the HCP group,400 μg· mL-1).After the cultivation of cells for 2 h,mRNA levels were measured by real-time RT-PCR,while phosphorylation levels of target proteins were detected by western blot after the treatment for 30 min.It was found that the cell viability indexes in the cells administered by 100,200 and 400 μg·mL-1 CP increased significantly compared with the control group (P＜0.01).After the administration for 2 h,InsR and IRS-2 mRNA expressions in the insulin group,the LCP group and the HCP group increased (P＜0.05 or P＜0.01).After the administration for 30 min,phosphorylation levels of InsRβ,IRS-2 and Akt in the insulin group were higher than those in the HCP group (P＜0.01).In conclusion,CP probably increased the cell viability of H4IIE cells,and improved the blood glucose index through enhancing the mRNA expressions of InsR and IRS-2 and the phosphorylation levels of InsRβ,IRS-2 and Akt in the liver.

A Research Progress on Cognitive Dysfunction and Diabetes Mellitus / 世界科学技术-中医药现代化

Diabetic cognitive dysfunction,a glucose metabolic disorder,is caused by metabolic,neurochemistrical,morphological,electrical physiological and behavioral changes featuring the disability of reasoning and learning,memory loss,inattention and hypophrenia.In recent years,more attention has been attached to the field of medicine.In this review,a progress of cognitive disorder was systematically explored over the pathogenesis and treatment of both TCM and western medicine,and investigated multi-targets and multiple methods of Chinese herbal researches at multiple stages for expanding the range of clinical application of TCM,enriching and developing the theory of TCM compatibility,and promoting the advantages of TCM syndrome differentiation.

Effect ofQiwei Granules on Renal Podocyte Injury in Diabetic Nephropathy Mice / 世界科学技术-中医药现代化

This article was aimed to study the effect ofQiwei granules on the podocyte in KK-Ay mice kidney. The 28 8-week-old male KK-Ay mice were randomly divided into the model group, low-dosage, middle-dosage and high-dosageQiwei granule group. Eight C57BL/6J mice were used as the normal control. The general conditions, blood glucose and 24 h albuminuria were recorded in the experiment. After 10-week treatment, renal indexes including serum creatinine and urea nitrogen were measured. The kidneys of mice were collected and measured. The hematoxylin and eosin (HE), Masson’s Trichrome, and periodic acid-Schiff (PAS) were used on renal tissues of mice. The immunohistochemical staining for WT-1 was made. Software analysis was combined in the calculation of renal podocyte amount. Western blot was used in the detection of nephrin protein expressions in the kidney of mice. RT-PCR was used in the detection of nephrin mRNA expression. The results showed that compared with the model group, the body weight, blood glucose, 24 h albuminuria and the serum creatinine were obviously decreased after 10-week treatment ofQiwei granules. It can effectively improve the glomerular mesangial proliferation and preserve the podocyte number. Meanwhile, after the treatment ofQiwei granules, the nephrin protein expression and mRNA expression were obviously higher than the model group. It was concluded thatQiwei granules probably managed nephrin expression to improve the podocyte injury in the diabetic nephropathy of KK-Ay mice.

Study on Action Mechanism of African Traditional HerbHypoxis Hemerocallidea Extracts on AMPK Signal Pathway of Skeletal Muscles in Diabetes / 世界科学技术-中医药现代化

This study was aimed to investigate the action mechanism ofHypoxis Hemerocallidea (African Potato, AP) on the AMPK signal pathway of skeletal muscles in diabetic rats. Among 40 male SD rats, 10 rats were used as the normal group, and the other 30 rats were fed with high-fat food for one month, and then injected with STZ for the model establishment. After the successful model establishment, rats were divided into the model group, pioglitazone hydrochloride group and the AP group. Intragastric administration was given for 5 weeks in each group. Then, the skeletal muscle tissues were embedded and sliced for immunohistochemistry test. The protein expression of p-AMPKα, p-AS16 and GLUT4 in skeletal muscles was detected by western blot. The 100 mmol·L-1 glucose was used in the establishment of C2C12 skeletal muscle cells insulin resistance model. AP drug-containing serum was used in the establishment of the treatment group. The control group was the normal cells. Glucose consumption, cell proliferation, SOD content, and MDA content were detected. And the protein expressions of p-AMPKα, p-AS160, GLUT4 were detected with the western blot and RT-PCR. The results showed that compared with the normal group, AP can up-regulate p-AMPKa protein express (P < 0.01), increase skeletal AS160 phosphorylation level (P < 0.01), and up-regulate the GLUT4 level (P < 0.01). Compared with the normal group, the high glucose caused the decrease of C2C12 skeletal muscle cell activity and the decrease of glucose consumption (P < 0.05), decrease of SOD, increase of MDA (P < 0.01), and the decrease of p-AMPKα, p-AS160, GLUT4 protein expression (P < 0.01). After 48 h intervention, the SOD of C2C12 skeletal muscle cells in the AP drug-containing serum group was significantly increased (P < 0.01), the MDA content was decreased (P < 0.05), the AMPKa and AS160 phosphorylation levels were increased (P < 0.01), the GLUT protein expression was increased (P < 0.01). It was concluded that the induced AMPKa and AS160 phosphorylation promoted GLUT 4 expression may be one of the action mechanism of insulin resistance of skeletal muscles in diabetes.