Background Insulin treatment plays a key role in management of diabetes mellitus. Clinical researches showed that extra improvements in restoration of insulin secretion of pancreatic β cells were found in patients w...Background Insulin treatment plays a key role in management of diabetes mellitus. Clinical researches showed that extra improvements in restoration of insulin secretion of pancreatic β cells were found in patients with newly diagnosed type 2 diabetes. The purpose of this study was to investigate the effects of early insulin treatment on insulin mRNA expression and morphological alterations of β cells in a Sprague Dawley (SD) rat model of type 2 diabetes. Methods A rat model of type 2 diabetes mellitus (T2DM) was induced by a high fat diet (high energy, HE) and low doses of streptozotoxin (STZ, 40 mg/kg). A group of diabetic rats was then injected with protamine zinc insulin (PZI, 1-2 U·kg -1·d -1) for one week. Insulin mRNA expression, morphological features of pancreatic islets, and metabolic parameters were examined in rats using reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry, and other techniques. Results In insulin-treated diabetic rats, insulin mRNA levels prominently increased by 81.3% (P<0.05), as compared with untreated diabetic rats. Moreover, timely insulin treatment noticeably improved the insulin content of β cells, with an increase of 10.2% (P<0.05), despite a slight reduction in fasting blood glucose (FBG), triglyceride (TG), and free fatty acid (FFA) levels, as compared to an untreated diabetic group. Conclusion Insulin treatment at the onset of T2DM effectively improves insulin synthesis, as confirmed by morphological changes to β cells in a rat model of type 2 diabetes.展开更多
Diabetic foot ulcers(DFU),which may lead to lower extremity amputation,is one of the severe and chronic complications of diabetic mellitus.This study aims to develop,and use dressings based on Silk fibroin(SF)as the s...Diabetic foot ulcers(DFU),which may lead to lower extremity amputation,is one of the severe and chronic complications of diabetic mellitus.This study aims to develop,and use dressings based on Silk fibroin(SF)as the scaffold material,gelatin microspheres(GMs)as the carrier for the neurotensin(NT),a neuropeptide that acts as an inflammatory modulator in wound healing and NT as accelerate wound healing drug to treat DFU.We evaluated the wound healing processes and neo-tissue formation in rat diabetic model by macroscopic observation,histological observation(H&E staining and Masson's trichrome staining)and immunofluorescence analysis at 3,7,14,21 and 28 post-operation days.Our results show that the NT/GMs/SF group performance the best not only in macroscopic healing and less scars in 28 post-operation days,but also in fibroblast accumulation in tissue granulation,collagen expression and deposition at the wound site.From release profiles,we can know the GMs are a good carrier for control release drugs.The SEM results shows that the NT/GMs/SF dressings have an average pore size are 40–80μm and a porosity of∼85%,this pore size is suit for wound healing regeneration.These results suggest that the NT/GMs/SF dressings may work as an effective support for control release NT to promote DFU wound healing.展开更多
Objective To study the antidiabetic effects and the underlying molecular mechanisms of Lycium barbarum polysaccharide(LBP) and its DEAE cellulose elution fraction LBP-IV in diabetic rats induced by high fat diet(HF...Objective To study the antidiabetic effects and the underlying molecular mechanisms of Lycium barbarum polysaccharide(LBP) and its DEAE cellulose elution fraction LBP-IV in diabetic rats induced by high fat diet(HFD) and streptozotocin(STZ). Methods After ig administration of LBP-IV [50, 100, and 200 mg/(kg·d)] and LBP [100 mg/(kg·d)] once daily for consecutive 4 weeks to diabetic rats, the glucose and lipids in blood, m RNA expression of phosphoenolpyruvate carboxykinase(PEPCK), sterol regulatory element binding-protein-1c(SREBP-1c), and fatty acid synthase(FAS) in liver were determined. Results Ig administration of LBP and LBP-IV significantly decreased the levels of blood glucose, Hb A1 c, TC, TG, and LDL-C, as well as the hepatic m RNA expression of PEPCK, SREBP-1c, and FAS, whereas significantly increased the oral glucose tolerance of diabetic rats. Conclusion The findings suggest that the antidiabetic effects of LBP and LBP-IV are associated with the decreased hepatic m RNA expression of PEPCK, SREBP-1c, and FAS in HFD-STZ induced diabetic rats.展开更多
文摘Background Insulin treatment plays a key role in management of diabetes mellitus. Clinical researches showed that extra improvements in restoration of insulin secretion of pancreatic β cells were found in patients with newly diagnosed type 2 diabetes. The purpose of this study was to investigate the effects of early insulin treatment on insulin mRNA expression and morphological alterations of β cells in a Sprague Dawley (SD) rat model of type 2 diabetes. Methods A rat model of type 2 diabetes mellitus (T2DM) was induced by a high fat diet (high energy, HE) and low doses of streptozotoxin (STZ, 40 mg/kg). A group of diabetic rats was then injected with protamine zinc insulin (PZI, 1-2 U·kg -1·d -1) for one week. Insulin mRNA expression, morphological features of pancreatic islets, and metabolic parameters were examined in rats using reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry, and other techniques. Results In insulin-treated diabetic rats, insulin mRNA levels prominently increased by 81.3% (P<0.05), as compared with untreated diabetic rats. Moreover, timely insulin treatment noticeably improved the insulin content of β cells, with an increase of 10.2% (P<0.05), despite a slight reduction in fasting blood glucose (FBG), triglyceride (TG), and free fatty acid (FFA) levels, as compared to an untreated diabetic group. Conclusion Insulin treatment at the onset of T2DM effectively improves insulin synthesis, as confirmed by morphological changes to β cells in a rat model of type 2 diabetes.
基金supported financially by the Natural Science Foundation of China(51303064 and 31271019)the Science and Technology Program of Guangzhou(201601010270,2017010160489,201704030083)+1 种基金the Pearl River S&T Nova Program of Guangzhou(201710010155,201806010072)the Science and Technology Project of Guangdong province(2015A010101313,2017A050506011,2017B090911012,2018A050506040,2018A050506019,2018A050506021).
文摘Diabetic foot ulcers(DFU),which may lead to lower extremity amputation,is one of the severe and chronic complications of diabetic mellitus.This study aims to develop,and use dressings based on Silk fibroin(SF)as the scaffold material,gelatin microspheres(GMs)as the carrier for the neurotensin(NT),a neuropeptide that acts as an inflammatory modulator in wound healing and NT as accelerate wound healing drug to treat DFU.We evaluated the wound healing processes and neo-tissue formation in rat diabetic model by macroscopic observation,histological observation(H&E staining and Masson's trichrome staining)and immunofluorescence analysis at 3,7,14,21 and 28 post-operation days.Our results show that the NT/GMs/SF group performance the best not only in macroscopic healing and less scars in 28 post-operation days,but also in fibroblast accumulation in tissue granulation,collagen expression and deposition at the wound site.From release profiles,we can know the GMs are a good carrier for control release drugs.The SEM results shows that the NT/GMs/SF dressings have an average pore size are 40–80μm and a porosity of∼85%,this pore size is suit for wound healing regeneration.These results suggest that the NT/GMs/SF dressings may work as an effective support for control release NT to promote DFU wound healing.
基金Sci-Tech Support Plan of Hubei province,China,No.2015BCA273
文摘Objective To study the antidiabetic effects and the underlying molecular mechanisms of Lycium barbarum polysaccharide(LBP) and its DEAE cellulose elution fraction LBP-IV in diabetic rats induced by high fat diet(HFD) and streptozotocin(STZ). Methods After ig administration of LBP-IV [50, 100, and 200 mg/(kg·d)] and LBP [100 mg/(kg·d)] once daily for consecutive 4 weeks to diabetic rats, the glucose and lipids in blood, m RNA expression of phosphoenolpyruvate carboxykinase(PEPCK), sterol regulatory element binding-protein-1c(SREBP-1c), and fatty acid synthase(FAS) in liver were determined. Results Ig administration of LBP and LBP-IV significantly decreased the levels of blood glucose, Hb A1 c, TC, TG, and LDL-C, as well as the hepatic m RNA expression of PEPCK, SREBP-1c, and FAS, whereas significantly increased the oral glucose tolerance of diabetic rats. Conclusion The findings suggest that the antidiabetic effects of LBP and LBP-IV are associated with the decreased hepatic m RNA expression of PEPCK, SREBP-1c, and FAS in HFD-STZ induced diabetic rats.