OBJECTIVES: To investigate the therapeutic mechanism of Danzhi Jiangtang Capsule (DZJTC) for repairing renal vascular endothelial injury in rats with diabetic nephropathy (DN). METHODS: Fifty male SD rat models of DN, established by left nephrectomy, high-sugar and high-fat diet and streptozotocin injection, were randomized into DN model group, low-, medium-, and high-dose DZJTC treatment groups, and DAPT (a γ-secretase inhibitor) treatment group, with 10 rats with normal feeding as the control group. DZJTC was administered by daily gavage at 0.315, 0.63, or 1.26 g/kg, and DAPT (20 mg/kg, dissolved in 50% CMC-Na solution) was given by gavage every other day for 4 weeks; normal saline was given in the control and model groups. After treatment, the levels of creatinine (CRE), blood urea nitrogen (BUN), and microalbuminuria (mALB) were detected with ELISA, and renal pathologies were observed by transmission electron microscopy. Renal expressions of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) were measured by immunohistochemistry, and the protein expressions of CD31 and Notch signaling pathway components were detected using Western blotting. RESULTS: The rat models of DN showed significantly increased CRE, BUN, and mALB levels, obvious renal pathologies under electron microscopy, increased renal VEGF, ET-1 and CD31 expressions, and upregulated Notch1, NICD, and MAML1 protein levels. Treatment with DZJTC at the 3 doses and DAPT significantly reduced CRE, BUN, and mALB levels, improved renal pathology, decreased VEGF, ET-1 and CD31 expressions, and lowered Notch1, NICD and MAML1 levels, and the effects were the most pronounced with high-dose DZJTC. CONCLUSIONS DZJTC ameliorates hyperproliferation and dysfunction of renal vascular endothelium in DN rats possibly by regulating renal VEGF and ET-1 levels via inhibiting NICD- and MAML1-mediated Notch signaling pathway.
Animals ; Male ; Drugs, Chinese Herbal/therapeutic use* ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/drug effects* ; Diabetic Nephropathies/drug therapy* ; Receptor, Notch1/metabolism* ; Kidney/blood supply* ; Diabetes Mellitus, Experimental ; Down-Regulation ; Endothelium, Vascular/metabolism* ; Nuclear Proteins/metabolism*

Blood glucose fluctuation leads to poor bone defect repair in patients with type 2 diabetes (T2DM). Strategies to safely and efficiently improve the bone regeneration disorder caused by blood glucose fluctuation are still a challenge. Neutral sphingophospholipase 2 (Smpd3) is downregulated in jawbone-derived bone marrow mesenchymal stem cells (BMSCs) from T2DM patients. Here, we investigated the effect of Smpd3 on the osteogenic differentiation of BMSCs and utilized exosomes from stem cells overexpressing Smpd3 as the main treatment based on the glucose responsiveness of phenylboronic acid-based polyvinyl alcohol crosslinkers and the protease degradability of gelatin nanoparticles. The combined loading of Smpd3-overexpressing stem cell-derived exosomes (Exos-Smpd3) and nanosilver ions (Ns) to construct a hydrogel delivery system (Exos-Smpd3@Ns) promoted osteogenesis and differentiation of BMSCs in a glucose-fluctuating environment, ectopic osteogenesis of BMSCs in a glucose-fluctuating environment and jawbone regeneration of diabetic dogs in vitro. Mechanistically, Smpd3 promoted the osteogenesis and differentiation of jawbone-derived BMSCs by activating autophagy in the jawbone and inhibiting macrophage polarization and oxidative stress caused by blood glucose fluctuations. These results reveal the role and mechanism of Smpd3 and the Smpd3 overexpression exosome delivery system in promoting BMSC function and bone regeneration under blood glucose fluctuations, providing a theoretical basis and candidate methods for the treatment of bone defects in T2DM patients.
Exosomes ; Animals ; Bone Regeneration/drug effects* ; Dogs ; Mesenchymal Stem Cells ; Humans ; Blood Glucose ; Cell Differentiation ; Osteogenesis/drug effects* ; Diabetes Mellitus, Type 2/therapy* ; Diabetes Mellitus, Experimental ; Cells, Cultured ; Hydrogels ; Male

In this study, insulin (insulin, INS)/Ca₃PO₄ complex and glucose oxidase (glucose oxidase, GOx)/Cu₃(PO₄)₂ complex were prepared by coprecipitation method. The mineralized insulin (mineralized insulin, m-INS) showed irregular crystalline clusters, and the mineralized glucose oxidase (m-GOx) showed flower spherical morphology, with a diameter of about 1-2 μm. In vitro simulated release experiment showed that m-INS released INS as the pH value of the medium decreased. When the pH value was 4.5, the release amount reached 96.68%. The enzyme activity detection experiment showed that the enzyme activity stability of m-GOx was higher than that of free GOx. It still maintained high activity after 10 days at room temperature, while the activity of GOx was less than 60%. The glucose solution was prepared to simulate the state of normal blood glucose (5.6 mmol/L) and hyperglycemia (22.2 mmol/L). When m-INS and m-GOx were added to the glucose solution, the release amount of INS showed a significant glucose concentration dependence. The higher the glucose concentration, the greater the release amount and release rate of INS. Finally, m-INS, m-GOx and hyaluronic acid (HA) solution were mixed to prepare HA microneedle arrays loaded with m-INS and m-GOx. Type 1 diabetes mice were constructed to evaluate the effect of drug-loaded HA microarray on blood glucose control in diabetic rats. The results show that the HA microneedles loaded with m-INS/m-GOx could deliver drugs effectively. The average blood glucose concentration in diabetic rats dropped to about 7 mmol/L within 1 h, normal blood glucose concentration could be maintained for 10 h, and the overall blood glucose concentration was lower than the level before administration for 36 hours. Compared with HA microneedles loaded with INS only, m-ins microneedles showed better glucose tolerance, longer-lasting glucose control effect and less risk of hypoglycemia. Compared with other sustained-release systems, the preparation process of the core components in this study is simple, efficient, safe and effective, and has great commercial potential.
Animals ; Blood Glucose ; Delayed-Action Preparations/therapeutic use* ; Diabetes Mellitus, Experimental/drug therapy* ; Drug Delivery Systems/methods* ; Glucose Oxidase/chemistry* ; Hyaluronic Acid ; I Blood-Group System ; Insulin/therapeutic use* ; Mice ; P Blood-Group System ; Rats

Diabetic nephropathy (DN) is one of the most common complications of diabetes mellitus, which is characterized in renal tubulointerstitial fibrosis (TIF). The current study was designed to investigate the protective effect of Jujuboside A (Ju A) on TIF in type 2 diabetes (T2DM) mice, and explore its underlying anti-fibrosis mechanism. A mouse T2DM model was established using high fat diet (HFD) feeding combined with intraperitoneal injection of streptozotocin (STZ). Then, diabetic mice were treated with Ju A (10, 20 and 40 mg·kg^-1·d^-1, i.g.) for 12 weeks. Results showed that administration of Ju A not only down-regulated fasting blood glucose (FBG) levels, but also improved hyperlipidemia and renal function in diabetic mice. Moreover, the reduced ECM accumulation was observed in the renal cortex of Ju A treated diabetic mice, while the TIF progression was also attenuated by Ju A through blocking the epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells (RTECs). Further mechanism studies showed that Ju A treatment effectively down-regulated the protein expression and subsequent nuclear translocation of Yin Yang 1 (YY1) in the renal cortex of diabetic mice, and reduced the levels of transforming growth factor-β1 (TGF-β1) in the serum and renal cortex of Ju A treated mice. According to invitro studies, the up-regulated YY1/TGF-β1 signaling pathway was restored by Ju A in high glucose (HG) cultured HK-2 cells. Taken together, these findings demonstrated that Ju A can ameliorate the TIF of DN through down-regulating the YY1/TGF-β1 signaling pathway.
Animals ; Blood Glucose ; Diabetes Mellitus, Experimental/metabolism* ; Diabetes Mellitus, Type 2/drug therapy* ; Diabetic Nephropathies/metabolism* ; Fibrosis ; Mice ; Saponins ; Signal Transduction ; Streptozocin ; Transforming Growth Factor beta1/metabolism*

Animals ; Berberine/pharmacology* ; Blood Glucose ; Diabetes Mellitus, Experimental/drug therapy* ; Diabetes Mellitus, Type 2 ; Insulin ; Insulin Resistance ; Rats

Objective To investigate the effects of simvastatin on diabetic neuropathic pain and systematic inflammation in diabetic rats and explore their molecular mechanisms.Methods Totally 24 rats were equally randomized into the normal+vehicle(NV)group,diabetic+vehicle(DV)group,and diabetic+simvastatin(DS)group using the random number table.Streptozotocin(STZ)was used to establish the rat models of diabetes.Blood glucose,body mass,paw withdrawal mechanical threshold(PWMT),and paw withdrawal thermal latency(PWTL)in each group were observed on days 7,14,21,and 28 after STZ injection.On day 28 after STZ injection,rats were sacrificed,and the lumbar spinal dorsal horn and serum were collected.Western blotting was used to detect the expression of receptor for advanced glycation end products(RAGE)and the phosphorylation levels of protein kinase B(AKT),extracellular signal-regulated kinase(ERK),p38,and c-Jun N-terminal kinase(JNK)in the spinal dorsal horn of rats in each group.Enzyme-linked immunosorbent assay was performed to determine the serum concentrations of oxidized low density lipoprotein(ox-LDL)and interleukin-1β(IL-1β).Results On days 14,21 and 28 after STZ injection,the PWMT in DV group were(8.6 ± 0.8),(7.1 ± 1.6),and(7.8 ± 0.8)g respectively,which were significantly lower than (12.0 ± 0.9)(=8.482, =0.000),(11.6 ± 1.5)(=11.309, =0.000),and(11.7 ± 1.5)g(=9.801, =0.000)in NV group.The PWMT in DS group on days 21 and 28 were(9.4 ± 1.4)(=5.780, =0.000)and(9.7 ± 0.9)g(=4.775, =0.003),respectively,which were significantly improved comparing with those of DV group.On days 7,14,21,and 28,there were no significant differences in PWTL among these three groups (all <0.05).The expression of RAGE in the spinal dorsal horn of DV group was significantly higher than those of NV group(=6.299, =0.000)and DS group(=2.891, =0.025).The phosphorylation level of AKT in the spinal dorsal horn of DV group was significantly higher than those of NV group(=8.915,=0.000)and DS group(=4.103,=0.003).The phosphorylation levels of ERK( =8.313,=0.000),p38( =2.965, =0.022),and JNK(=7.459, =0.000)in the spinal dorsal horn of DV group were significantly higher than those of NV group;the phosphorylation level of JNK in the spinal dorsal horn of DS group was significant lower than that of DV group(=3.866, =0.004);however,there were no significant differences in the phosphorylation levels of ERK(=1.987,=0.122)and p38(=1.260,=0.375)in the spinal dorsal horn between DS group and DV group.The serum concentrations of ox-LDL and IL-1β in DV group were(41.86 ± 13.40)ng/ml and(108.16 ± 25.88)pg/ml,respectively,which were significantly higher than those in NV group [(24.66 ± 7.87)ng/ml(=3.606,=0.003)and(49.32 ± 28.35)pg/ml(=5.079,=0.000)] and DS group [(18.81 ± 5.62)ng/ml (=4.833, =0.000)and(32.73 ± 11.73)pg/ml(=6.510, =0.000)].Conclusions Simvastatin can relieve the mechanical allodynia of diabetic rats possibly by inhibiting the activation of RAGE/AKT and the phosphorylation of JNK in the spinal dorsal horn.Simvastatin can also decrease the serum concentrations of ox-LDL and IL-1β in diabetic rats,which may contribute to the relief of systematic inflammation.
Animals ; Diabetes Mellitus, Experimental ; complications ; Hyperalgesia ; Inflammation ; drug therapy ; Interleukin-1beta ; blood ; Lipoproteins, LDL ; blood ; Neuralgia ; drug therapy ; Proto-Oncogene Proteins c-akt ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptor for Advanced Glycation End Products ; metabolism ; Simvastatin ; pharmacology

OBJECTIVE: To investigate the therapeutic effects of puerarin on rats with type 2 diabetes mellitus (T2DM). METHODS: T2DM models were established by high fat and high glucose feeding combined with a one-time intraperitoneal injection of streptozotocin (STZ, 60 mg/kg). Then the rats were randomly divided into normal group, model group, metformin group (MET, 40 mg/kg), puerarin low-dose group, medium-dose group and high-dose group (40, 80, 160 mg/kg), n=10. After the model was successfully established, rats were treated with corresponding drug intervention by intragastrical administration for 4 weeks. The body weight and fasting blood glucose (FBG) were measured per week, and blood samples were collected 24 h after the last administration, and serum levels of blood glucose, serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholestrol (HDL-C), serum enzyme activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), serum creatinine (SCr), and blood uric acid (UA) were measured. RESULTS: As compared with normal group, the body weight was decreased after 4 weeks-intervention in the model group, and the levels of FBG, TC, TG, LDL-C, ALT, AST, BUN, SCr and UA were all increased,while HDL-C level was decreased (P＜0.05). As compared with model group,the body weight was increased after 4 weeks-intervention in metformin group and puerarin groups, and the levels of FBG, TC, TG, LDL-C, ALT, AST, BUN, SCr and UA were decreased (P＜0.01); meanwhile, HDL-C level was increased significantly (P＜0.05). CONCLUSION Puerarin can reduce the weight loss of T2DM rats, decrease the blood lipid and blood glucose levels of T2DM rats, which can be used to control T2DM.
Animals ; Blood Glucose ; Diabetes Mellitus, Experimental ; drug therapy ; Diabetes Mellitus, Type 2 ; drug therapy ; Isoflavones ; pharmacology ; Lipids ; blood ; Random Allocation ; Rats ; Streptozocin ; Weight Loss

Diabetic cardiomyopathy( DCM) is one of the major cardiovascular complications of diabetes mellitus. Based on the clinical efficacy of Danzhi Jiangtang Capsules( DJC) in the prevention and treatment of diabetes and its cardiovascular complications,both in vivo and in vitro methods were adopted to investigate its effect and underlying mechanism of protecting myocardial injury induced by diabetes. The type 2 diabetic rats were prepared by feeding high-energy food combined with streptozotin( STZ) injection,and the effects of DJC were observed by blood sugar,blood lipid,hemodynamic index,cardiac weight index and the change of cardiac pathological morphology. The protein expressions of TLR4,MyD88 and NF-κB p65 in myocardial tissue were detected and the possible mechanism was preliminarily analyzed. Besides this,DJC containing serum was prepared,H9 c2 cardiomyocyte induced by high sugar were studied to investigate the mechanism of TLR4/MyD88/NF-κB signaling pathway regulating cardiomyocyte injury and the therapeutic effect of DJC. The results demonstrated that fasting blood sugar,glycosylated hemoglobin,total cholesterol and glycerol triglyceride were significantly reduced( P<0. 01,P<0. 05). Cardiac weight index,left ventricle weight index,LVEDP and the protein expressions of TLR4,MyD88 and NF-κB p65 were significantly reduced( P<0. 01,P<0. 05). LVSP,+dp/dtmaxand-dp/dtmaxincreased significantly( P<0. 01,P< 0. 05). Moreover,the pathological damage of myocardial tissue in rats improved significantly. Meanwhile,the protein expressions of TLR4,MyD88 and NF-κB p65 in cardiomyocytes induced by high sugar were significantly inhibited( P<0. 01).It showed that DJC were effective in preventing and treating myocardial injury induced by diabetes and its mechanism may be related to the over-expression of TLR4/MyD88/NF-κB signaling pathway induced by high sugar.
Animals ; Blood Glucose ; Capsules ; Diabetes Mellitus, Experimental/complications* ; Diabetic Cardiomyopathies/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Myeloid Differentiation Factor 88/metabolism* ; NF-kappa B/metabolism* ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Toll-Like Receptor 4/metabolism*

OBJECTIVES: To investigate the effects of saffron aqueous extract (SE) on blood glucose, lipid and pancreatic tissue in streptozocin-induced diabetes mice. METHODS: Diabetes mellitus mice were established by intraperitoneal injection of streptozocin (60 mg/kg) for two consecutive days. The 30 well-established diabetes mice were randomly divided into three groups(=10):diabetic mellitus (DM) group, SE treated (SE) group and positive control (metformin hydrochloride, MH) group. Another ten normal mice were selected as normal control (NC) group. The mice in SE and MH groups were intragastrically administered with SE 100 mg/kg or MH 100 mg/kg once a day for 6 weeks, mice in DM and NC were given normal saline. The amount of food-intake, water consumption and body weight were measured weekly, the changes of the indicators including fasting blood glucose (FBG), oral glucose-tolerance test (OGTT), glycated serum protein (GSP), insulin (INS) and blood lipid were determined after 6 weeks of continuous administration. The pathologic changes in the pancreas tissues were detected by HE staining. RESULTS: Compared with the normal control group, the amount of food-intake, water consumption, area under the curve, FBG, GSP, and total cholesterol (TC) were significantly increased, while fasting weight, INS and high density lipoprotein cholesterol (HDL-c) were dramatically decreased in DM group. Compared with DM group, the water consumption, FBG, area under the curve and TC in SE group were starkly declined with a notable elevation of HDL-c and INS. In addition, the biopsy from DM mice showed the structure of pancreas islet was destroyed and reduced, and vascular proliferation with irregular shape. The damaged pancreas was obviously repaired by giving SE. CONCLUSIONS The saffron aqueous extract had efficacy on blood glucose and blood lipids reduction, improvement on damaged pancreas in streptozocininduced diabetic mice, which suggested that saffron could be used for the treatment in diabetes.
Animals ; Blood Glucose ; Crocus ; chemistry ; Diabetes Mellitus, Experimental ; chemically induced ; drug therapy ; Hypoglycemic Agents ; pharmacology ; Insulin ; blood ; Mice ; Plant Extracts ; pharmacology ; Random Allocation ; Streptozocin

OBJECTIVES: To study the effects of ursolic acid on liver injury in diabetic mice induced by high-fat diet combined with streptozotocin(STZ), and to explore its possible mechanisms. METHODS: Diabetes mellitus was induced in twenty male ICR mice by a combination of high-fat diet for 6 weeks with low-dose streptozotocin (30 mg/kg, i. p.) for 5 consecutive days. After 9 days, fasting blood glucose levels were determined. Mice with fasting blood glucose levels exceeded 11. 1 mmol/L were diagnosed as diabetic mice and selected for further experiment. These mice were randomly divided into two groups(each group of 10):diabetic group, ursolic acid group (100 mg/kg, i. g.), and another 10 mice were set as control group. After continuous administration for 8 weeks, body weight (BW) were weighed, fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT), aspartate transaminase (AST) in serum and superoxide dismutase (SOD), malondialdehyde (MDA) in liver were measured. HE staining was used to observe pathological changes of liver tissue. RESULTS: Compared with the control group, the level of FBG, TC, TG, ALT, AST, MDA were dramatically increased (<0. 05, <0. 01) and SOD was markedly decreased (<0.01) in the diabetic group; HE staining showed that parts of liver cells swelled and had a light fatty degeneration as well as lymphocyte infiltrated around the portal area in model group. Compared with the diabetic group, the level of FBG, TC, TG, ALT, AST, MDA were significantly declined (<0.05, <0.01) and SOD was considerably increased (<0.01) in the ursolic acid group; HE staining showed that the liver cells relatively arranged in order, edema was not obvious and inflammatory cells infiltrated lightly in the ursolic acid group. CONCLUSIONS Ursolic acid has a protective effect on liver injury in diabetic mice induced by high-fat diet combined with STZ by intraperitoneal ingector, and its mechanism may be associated with lowering blood glucose, regulating the lipid metabolism, reducing oxidative stress and enhancing the ability of anti-oxidation in liver.
Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Blood Glucose ; Cholesterol ; blood ; Diabetes Mellitus, Experimental ; physiopathology ; Diet, High-Fat ; Fatty Liver ; drug therapy ; Liver ; metabolism ; physiopathology ; Male ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred ICR ; Random Allocation ; Superoxide Dismutase ; metabolism ; Triglycerides ; blood ; Triterpenes ; pharmacology