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ObjectiveTo observe the effects of Hedysari Radix polysaccharide on the apoptosis of gastric sinus smooth muscle cells and explore the underlying mechanism via the insulin-like growth factor-1 （IGF-1）/phosphatidylinositol 3-kinase （PI3K）/serine-threonine kinase （Akt） pathway in the rat model of diabetic gastroparesis （DGP）. MethodSixty-two Wistar male rats were randomized into a blank group （n=12） and a modelling group （n=50）. The rat model of DGP was established by small-dose multiple intraperitoneal injections of streptozotocin combined with an irregular high-fat and high-sugar diet for 4 weeks. The modeled rats were randomized into model group， mosapride citrate （1.35 mg·kg-1）， and high-， medium-， and low-dose （200， 100， and 50 mg·kg-1， respectively） Hedysari Radix polysaccharide groups. The rats were administrated with corresponding drugs by gavage， and those in the blank and model groups with equal volumes of pure water by gavage once a day for 8 consecutive weeks. The random blood glucose and body mass were measured every 2 weeks， and gastric emptying rate was calculated. Hematoxylin-eosin （HE） staining was used to observe the pathological changes of smooth muscle in gastric antrum， and terminal deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to detect the apoptosis of smooth muscle cells in the gastric antrum. The expression of IGF-1， phosphorylated （p）-PI3K， and p-Akt in the smooth muscle of gastric sinus tissue was detected by immunohistochemistry. Western blot was employed to determine the protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） in the smooth muscle of the gastric antrum. ResultCompared with the blank group， the model group showed elevated random blood glucose at all time points （P<0.01）， decreased body mass and gastric emptying rate （P<0.01）， increased apoptotic index of smooth muscle cells in the gastric antrum （P<0.01）， down-regulated protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， and Bcl-2， and up-regulated protein level of Bax （P<0.01）. Compared with the model group， the 8 weeks of drug administration lowered the random blood glucose， increased the body mass and gastric emptying rate （P<0.05， P<0.01）， decreased the apoptotic index of smooth muscle cells in the gastric antrum （P<0.05， P<0.01）， up-regulated the protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， and Bcl-2， and down-regulated the protein level of Bax （P<0.05， P<0.01）. Compared with the mosapride citrate group，the administration of low-dose Hedysari Radix polysaccharide for 6 and 8 weeks lowered the random blood glucose and decreased the body mass （P<0.05， P<0.01），low and medium-dose Hedysari Radix polysaccharide decreased the gastric emptying rate and the apoptotic index of smooth muscle cells in the astragaloside low-dose group decreased （P<0.05）. The protein levels of IGF-1，p-PI3K/PI3K，p-Akt/Akt and Bcl-2（low dose）were down-regulated and the protein level of Bax was up-regulated by low doses of Hedysari Radix polysaccharide （P<0.05， P<0.01）. Compared with high-dose Hedysari Radix polysaccharide， low-dose Hedysari Radix polysaccharide elevated random blood glucose and reduced body mass after 6 and 8 weeks of administration （P<0.05， P<0.01）， and the low and medium doses decreased the gastric emptying rate， increased the apoptotic index of smooth muscle cells in the gastric antrum （P<0.05， P<0.01）， down-regulated the protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， and Bcl-2， and up-regulated the protein level of Bax （P<0.05， P<0.01）. Compared with the medium-dose group，the low-dose group of Hedysari Radix polysaccharide had lower body mass，lower gastric emptying rate in rats，higher apoptotic index of smooth muscle cells in gastric sinus tissue after 6 and 8 weeks of administration （P<0.05， P<0.01）， and lower protein expression of IGF-1，p-PI3K/PI3K，p-Akt/Akt. ConclusionHedysari Radix polysaccharide protects the smooth muscle cells in gastric antrum against apoptotic injury and promotes gastric motility by activating the IGF-1/PI3K/Akt signaling pathway， as manifested by the up-regulated expression of IGF-1， p-PI3K， p-Akt， and Bcl-2 and down-regulated expression of Bax.
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OBJECTIVE@#To investigate the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in multiple myeloma (MM) patients, and analyze the effect of doxycycline (DOX) on the expression of MMP-2 and MMP-9 in MM cells.@*METHODS@#The peripheral blood and bone marrow samples of MM patients were collected, and the patients were divided into three groups: newly diagnosed group, remission group and relapsed/refractory group, while the peripheral blood samples of 34 health people and the bone marrow samples of 17 IDA patients were selected as normal control and control group. The levels of MMP-2 and MMP-9 were detected by ELISA. The protein levels of MMP-2 and MMP-9 in H929 cells treated by different concentrations of DOX were analyzed by Western blot. After H929 cells was treated by Akt inhibitor MK-2206 2HCl in combination with DOX, Western blot was used to detect the levels of MMP-2 and MMP-9.@*RESULTS@#The levels of MMP-2 and MMP-9 in newly diagnosed MM patients were higher than those in control (P<0.05), while for the patients in the remission group were decreased, but still higher than those in control. The levels of MMP-2 and MMP-9 were increased again for the patients in relapsed/refractory group, and showed no significant difference as compared with those in newly diagnosed group. The levels of MMP-2 and MMP-9 could be inhibited by 10 mg/L and 15 mg/L DOX treated by H929 cell. The protein levels of MMP-2 and MMP-9 showed no altered in H929 cells treated by 5 nmol/L MK-2206 2HCl alone. DOX exerted more profound inhibitory effect to MMP-2 and MMP-9 expression in H929 cells when Akt inhibitor MK-2206 2HCl was combined with DOX.@*CONCLUSION@#The levels of MMP-2 and MMP-9 are increased in MM patients and related to the disease status of MM. DOX can inhibit the expression of MMP-2 and MMP-9 in MM cells, and antagonizing its activation of Akt signaling pathway can further enhance the inhibitory effect.
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Humans , Doxycycline/pharmacology , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Multiple Myeloma/metabolism , Proto-Oncogene Proteins c-aktABSTRACT
Objective:To study the effect of Shuangshen Xionglian （SSXL） granules on vasculopathy and phosphatidylinositol 3 kinase （PI3K）/serine threonine kinase （Akt）/nitrogen oxide synthase （eNOS） signal in hyperhomocysteinemia chronic kidney disease rats. Method:Rats were randomly divided into 5 groups： sham operation group， model group， and high， medium and low-dose （8， 4， 2 g·kg-1） SSXL groups. The model of hyperhomocysteinemia chronic kidney disease in rats was established with high methionine feed combined with 5/6 nephrectomy. After 5/6 nephrectomy， continuous intragastric administration lasted for four weeks. Arterial blood pressure was measured at the 4th and 8th weeks after operation. At the end of the 8th week after the operation， blood was collected to determine serum creatinine， urea nitrogen， homocysteine （Hcy）， methionine and blood lipid. Western blot was used to detect the expressions of PI3K/Akt/eNOS pathway-related proteins， such as p-p85， p-Akt and p-Ser177 in thoracic aorta， and serum NO and eNOS were measured. The changes of endothelium-dependent relaxation and non-endothelium-dependent relaxation were measured by the method of isolated thoracic aorta ring. Pathological htoxylin eosin （HE） staining was used to observe the changes of renal tissue and thoracic aorta. Result:At the 8th week of the experiment， compared with the sham operation group， arterial systolic blood pressure， serum urea nitrogen， creatinine， Hcy， methionine， total cholesterol and low-density lipoprotein of the model group were significantly increased. Four weeks later after administration， arterial systolic blood pressure， serum urea nitrogen， Hcy， methionine， serum total cholesterol and serum low-density lipoprotein were significantly reduced in each dose group （P<0.05， P<0.01）. The creatinine in the SSXL 8， 4 g·kg-1 group was significantly reduced （P<0.05）. The nitric oxide content of SSXL in each dose groups were increased compared with that in the model group （P<0.05， P<0.01）， and the serum eNOS activity of the SSXL in the SSXL 8 g·kg-1 group was significantly increased compared with that in the model group （P<0.05）. The endothelium dependent and non-endothelium dependent vasodilation of thoracic aortic rings in the model group were significantly damaged. The cumulative concentration of acetylcholine （1×10-5.5~1×10-4 mmo1·L-1） in the SSXL 8 g·kg-1 group was significantly improved （P<0.05， P<0.01）. The diastolic degree of the vascular ring in the SSXL 8 g·kg-1 group was significantly higher than that in the model group （P<0.05）. Western blot results showed that the expressions of p-85， p-Akt and p-Ser177 in blood vessels increased in the sham group compared with those in the model group （P<0.01）. Compared with the model group， the phosphorylation level of this pathway was increased in the SSXL groups， and the expressions of p-Akt and p-Ser177 in the SSXL 8 g·kg-1 group were significantly increased （P<0.05）. The pathological results showed that the pathological changes of thoracic aorta and renal tissue in the dosages of SSXL were significantly reduced compared with those in the model group. Conclusion:SSXL granules can improve hyperhomocysteine and dyslipidemia in rats of chronic kidney disease with hyperhomocysteine， reduce serum creatinine， urea nitrogen levels and arterial systolic blood pressure， and improve vascular morphology and diastolic function， which may be related to the regulation of the PI3K/Akt/eNOS signaling pathway.
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Objective: To investigate effect of Yanghe Huayan Tang and phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 in intervening expressions of human epidermal growth factor receptor human epidermal growth factor receptor-2(HER-2), PI3K and phosphorylated serine/threonine kinase (p-Akt)in PI3K/Akt pathway of breast cancer cell line SK-BR-3 (HER-2 high expression) in vitro, and study intervention mechanism of Yanghe Huayan Tang. Method: Yanghe Huayan Tang intestinal absorption fluid was prepared, breast cancer cell strain SK-BR-3 was divided into blank group, Yanghe Huayan Tang group, LY294002 group, LY294002+Yanghe Huayan Tang group. The concentration was respectively 125 g·L-1 for Yanghe Huayan Tang, 0.05 g·L-1 for LY294002, 125 g·L-1 for Yanghe Huayan Tang+LY294002.The expressions of HER-2, PI3K and p-Akt protein were detected by immunohistochemistry and Western blot after 24 h. The most appropriate and effective concentration was obtained through extensive experiments. The expressions of HER-2, PI3K and p-Akt were detected by reverse transcription polymerase chain reaction (RT-PCR). Result: Compared with blank group, LY294002 group, and LY294002+Yanghe Huayan Tang group could inhibit protein and mRNA expressions of HER-2, PI3K, p-Akt in breast cancer cell lines(PPPPConclusion: Yanghe Huayan Tang can inhibit angiogenesis and invasion of breast cancer. Its main mechanism is expressed by intervening PI3K/Akt pathway, reducing expressions of HER-2, PI3K and p-Akt in pathway.
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Objective To explore the time and dose effects of AKT (a kind of protein serine/threonine kinase) inhibitor GSK2141795 on the apoptosis of human hepatocellular cell line Huh7. Methods Huh7 cells were treated with GSK2141795 at the concentrations of 0, 0.3, 1, 3, 10 and 30 µmol/L for 24 h. A concentration of 10 µmol/L GSK2141795 was selected to treat Huh7 cells for 0, 2, 6, 12, 24 and 48 h. The protein expression levels of AKT and phosphorylated AKTS473 (p-AKTS473) were determined by Western blotting and cell apoptosis was detected by flow cytometry. The expression levels of apoptosis-related proteins (Bad, Bcl-2 and Caspase-9) were measured by qPCR and Western blotting. Results With the increase of GSK2141795 concentration, AKT protein level in Huh7 cells was gradually decreased and the p-AKTS473 protein level was gradually increased within the range of 0-10 µmol/L. With the prolongation of GSK2141795 treatment time, the AKT protein level was gradually decreased and the p-AKTS473 protein level was gradually increased within the range of 0-24 h. At 48 h of treatment, the AKT protein and p-AKTS473 protein expression levels were increased compared with 0 h. With the increase of GSK2141795 concentration and treatment time, the proportion of apoptotic cells was gradually increased, the expression levels of apoptotic molecules Bad and Caspase-9 were gradually increased, and the expression level of apoptotic antagonist Bcl-2 was gradually decreased. Conclusion AKT inhibitor GSK2141795 can effectively inhibit AKT protein expression, and induce apoptosis of Huh7 cells through Bad-Bcl-2 pathway in a dose-and time-dependent manner. In addition, the expression level of AKT protein in Huh7 cells can increase again after long-term stimulation by GSK2141795, suggesting the existence of a negative feedback signal loop.
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AIM:To investigate matrine-induced apoptosis of human medulloblastoma D 341 cells and the ex-pression of Bax , Bcl-2, serine/threonine kinase Akt and phosphorylated Akt ( p-Akt) in vitro.METHODS: D341 cells were divided into experimental groups ( added with matrine at different concentrations ) and control group ( under the same conditions without matrine).The proliferation of D341 cells was analyzed by CCK-8 assay.Apoptosis was detected by An-nexin V-FITC/PI double staining and the expression of Bax , Bcl-2, Akt and p-Akt was detected by Western blotting .RE-SULTS:Matrine significantly inhibited the proliferation of D 341 cells and increased the apoptosis in a dose-and time-de-pendent manner .The cell apoptosis was characterized by chromatin condensation with margination of chromatin to the nu -clear membrane , increased when and larger cytoplasmic vacuoles , and formation of apoptotic body after treatment with ma-trine.The expression of Bax increased , while the expression of Bcl-2 and p-Akt decreased when the drug concentration gradually increased .CONCLUSION:Matrine induces the apoptosis of human medulloblastoma D 341 cells in vitro by acti-vation of Bax, down-regulation of Bcl-2 and reduction of p-Akt expression level in the PI3K/Akt signaling pathway.
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@#ObjectiveTo investigate the role of serine/threonine kinase (Akt) and lipoprotein lipase (Lpl) in formation of nonalcoholic steatohepatitis (NASH) in rat with a fat-rich diet.Methods40 male Wistar rats were randomly divided into the 8-week-rich-fat group (n=10), 8-week-common-diet control group (n=10), 12-week-rich-fat group (n=10) and 12-week-common-diet control group (n=10). The lipid, cholesterol, glucose and insulin were examined, insulin resistance index (IRI) and insulin sensitivity index (ISI) were calculated, the expression of Akt and Lpl were detected with immunohistochemical method and morphological changes of liver were observed by transmission electron microscope (TEM).ResultsNASH was formed in each rat of 8-week-rich-fat group with characteristics of individual obese, increased liver volume, full and clear contour, gray-yellowish luster, greasy section and crisp quality. And it was accompanied by high lipoidemia (HL), liver fat cell denaturation, inflammatory cell infiltration in liver lobuler and cell death in liver. The expression of Akt was obviously reduced and the expression of Lpl was obviously weakened in liver. Lipid, cholesterol, glucose and insulin and IRI were gradually advancing. ISI was reducing and the insulin resistance formed. The data of fat-rich diet groups was significantly different with that of common-diet control groups (P<0.0001).Conclusion Steatohepatitis and insulin resistance can form in rat by feeding with rich-fat diet for 8 weeks. It causes the insulin and Lpl activeness reducing, and steatolysis barrier.