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Objective: To study the toxicity features of high glucose on the endothelial cell cycle and the influence of Dan Gua-Fang (丹瓜方), a Chinese herbal compound prescription, on the reproductive cycle of vascular endothelial cells cultivated under a high glucose condition; to reveal the partial mechanisms of Dan Gua-Fang in the prevention and treatment of endothelial injury caused by hyperglycemia in diabetes mellitus (DM); and offer a reference for dealing with the vascular complications of DM patients with long-term high blood glucose. Methods: Based on the previous 3-(4,5)-dimethylthiahiazo (z-y1)-3-5-diphenytetrazoliumromide (MTT) experiment, under different medium concentrations of glucose and Dangua liquor, the endothelial cells of vein-304 (ECV-304) were divided into 6 groups as follows: standard culture group (Group A, 5.56 mmol/L glucose); 1/300 herb-standard group (Group B); high glucose culture group (Group C, 16.67 mmol/L glucose); 1/150 herb-high glucose group (Group D); 1/300 herb-high glucose group (Group E); and 1/600 herb-high glucose group (Group F). The cell cycle was assayed using flow cytometry after cells were cultivated for 36, 72 and 108 h, respectively. Results: (1) The percentage of cells in the G/G phase was significantly increased in Group C compared with that in Group A ( P<0.05), while the percentage of S-phase (S%) cells in Group C was significantly reduced compared with Group A ( P<0.05); the latter difference was dynamically related to the length of growing time of the endothelial cells in a high glucose environment. (2) The S% cells in Group A was decreased by 30.25% (from 40.23% to 28.06%) from 36 h to 72 h, and 12.33% (from 28.06% to 24.60%) from 72 h to 108 h; while in Group C, the corresponding decreases were 23.05% and 21.87%, respectively. The difference of S% cells between the two groups reached statistical significance at 108 h ( P<0.05). (3) The percentage difference of cells in the G/M phase between Group C and Group A was statistically significant at 72 h ( P<0.01). (4) 1/300 Dan Gua-Fang completely reversed the harmful effect caused by 16.67 mmol/L high glucose on the cell cycle; moreover it did not disturb the cell cycle when the cell was cultivated in a glucose concentration of 5.56 mmol/L. Conclusions: High glucose produces an independent impact on the cell cycle. Persistent blocking of the cell cycle and its arrest at the G/G phase are toxic effects of high glucose on the endothelial cell cycle. The corresponding variation of the arrest appears in the S phase. 1/300 Dan Gua-Fang completely eliminates the blockage of high glucose on the endothelial cell cycle. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the relationship between diabetes mellitus and pulposis and the pathogenesis of diabetes mellitus pulposis, via comparing the pulp tissue conditions and ultramicrostructures of capillary vessels in pulp tissues of diabetes mellitus patients and normal control. METHODS: Pulp tissues were obtained from clinically extracted human third molars with impaction (control group, 30 cases) and intact third molars with impaction (non-insulin . dependent diabetes patients) whilst without pulposis symptom (diabetic group, 30 cases). The pathological changes of two groups' pulp tissues were evaluated under light microscope and electron microscopy. The thickness of pulp capillary basement membrane and their anionic sites were quantitatively analyzed by electron microscopy and special staining. Statistical analysis was performed using SAS6.12 software package. RESULTS: The tricked blood capillary wall was observed in diabetic pulp under light microscope. The thickened blood capillary wall and constrictive lumen were observed in diabetic pulp under electron microscope, accompanied with vascular endothelial cell swelling and structural destruction and thickened basement membrane (P<0.01). The decrease of anionic sites of capillary basement membrane was observed in diabetic pulp under specially stained electron microscope (P<0.01). CONCLUSIONS: Inflammatory reaction existed in the pulp of intact teeth of DM patients without symptoms. The changes observed in diabetic vessels may occur in the dental pulp. Diabetes mellitus is closely related to pulposis. Supported by Projects of Shanghai Municipal Health Bureau (2008156). [ABSTRACT FROM AUTHOR]

In article number 1802250 Qing Lin, Ling Zhang, and co‐workers report an artificial "closed‐loop" structure for intravenous glucose‐responsive insulin delivery. An acid‐sensitive matrix forms the "inner core" and RBCm‐derived coating the "outer shell". Under hyperglycemic condition, the glucose internalized by the anchored glucose transporters is enzymatically converted into gluconic acid and subsequently triggers acid degradation of the "inner core" to secrete insulin. [ABSTRACT FROM AUTHOR]

An artificial "closed‐loop" system that mimics the glucose‐responsive insulin secretion of pancreas β‐cells can potentially improve the treatment efficacy for diabetes. Herein, a lipid bilayer‐coated polymeric nanoparticle (NP) with "core–shell" structure is designed. As far as it is known, it is the first and only intravenous nanoplatform utilizing enzymatic‐oxidation scheme to achieve glucose‐responsive insulin delivery so far. Ethoxy acetal–derivatized dextran nanoparticles (Ace‐DEX NPs) are constructed as "inner core" loaded with insulin, and coloading glucose oxidase (GOx) and catalase (CAT) endow the "inner core" excellent glucose‐sensitive ability. Red blood cell membrane (RBCm)‐derived coating is adopted as "outer shell." It collectively provides a closed microenvironment for GOx‐based enzymatic‐oxidation scheme and camouflages it from elimination. Above all, the anchored glucose transporters (GLUTs) on the "outer shell" are able to sense blood glucose levels and facilitate the transport of outer blood glucose getting inside. Under a hyperglycemic condition, the internalized glucose is catalytically converted into gluconic acid with the aid of the GOx and subsequently triggers acid degradation of the "inner core" to secrete insulin. By governing the blood glucose levels on an automatic and continuous basis, the RBCm‐Ace‐DEX NPs can effectively respond to hyperglycemia and turn to resting conditions under normoglycemia. Ethoxy acetal derivatized dextran nanoparticles (Ace‐DEX NPs) are constructed as "inner core" and red blood cell membrane (RBCm)‐derived coating is adopted as "outer shell". This glucose‐responsive nanoplatform can steadily circulate in the blood at normalglycemia. While under hyperglycemic condition, the glucose internalized by the anchored GLUTs is catalytically converted into gluconic acid with the aid of GOx and CAT and subsequently triggers acid degradation of RBCm‐Ace‐DEX NPs to secrete insulin. [ABSTRACT FROM AUTHOR]

In our previous study, a polysaccharide was extracted from Schisandra Chinensis (Trucz.) Baill and found with anti-diabetic effects. The aim of this study was to investigate the anti-diabetic effects of the low weight molecular polysaccharide (SCPP11) purified from crude Schisandra polysaccharide and illustrate the underlying mechanism in buffalo rat liver cells. The insulin resistance model of BRL cells was established by incubating with insulin solution for 24 h. The effects of SCPP11 on regulating related protein and mRNA expression in an insulin and AMPK signal pathway were investigated by western blot and RT-PCR analysis. SCPP11 showed no cytotoxicity to BRL cells and could improve the glucose consumption in BRL cells. SCPP11 increased the protein expression of Akt, p -AMPK and GLUT-4 in BRL cells. Moreover, SCPP11 could enhance the mRNA expression levels of IRS-1, PI3K, Akt, GLUT-4, AMPKα and PPAR-γ in BRL cells at the same time. In conclusion, SCPP11 possessed effects in improving glucose consumption by up-regulating the expression of GLUT-4 which might occur via insulin and AMPK signal pathway and could be a potential functional food to prevent and mitigate the insulin resistance condition. [ABSTRACT FROM AUTHOR]