Effective healing of diabetic skin wounds by using nonviral gene therapy based on minicircle vascular endothelial growth factor DNA and a cationic dendrimer.

BACKGROUND: The development of an efficient method to improve the wound healing process is urgently required for diabetic patients suffering a threat of limb amputations. Various growth factors have been proposed for treatment; however, more research still has to be carried out to maintain their curative effect. In the present study, we describe a simple nonviral gene therapy method for improving wound healing. METHODS: Minicircle plasmid DNA encoding vascular endothelial growth factor (VEGF) was combined with an arginine-grafted cationic dendrimer, PAM-RG4. The formed complexes were injected subcutaneously into the skin wounds of diabetic mice. RESULTS: Actively proliferating cells in wound tissue were efficiently transfected, resulting in a high level of VEGF expression. Within 6 days after injection, skin wounds in the diabetic mice were generally healed and displayed a well-ordered dermal structure, which was confirmed by histological staining. CONCLUSIONS: This simple and effective gene therapy method may represent a powerful tool for the treatment of diabetic foot ulcers and other diseases that are refractory to treatment.

The effect of gonadotrophin-releasing hormone agonist treatment over 3 years on bone mineral density and body composition in girls with central precocious puberty.

OBJECTIVE: Puberty is a period characterized by growth spurt and rapid change in body composition. The effect of GnRH agonist therapy for central precocious puberty on bone mineral density is unclear. We demonstrated changes in bone mineral density in subjects with central precocious puberty, who were treated with GnRH agonist for more than 3 years. DESIGN: The changes in bone mineral density and body compositions were tested with analysis of variance with repeated measures to identify statistical significance over the treatment period. PATIENTS: One hundred ninety-five Korean girls with central precocious puberty were treated with GnRH agonist, and among these subjects, 39 patients were treated for more than 3 years. MEASUREMENTS: Dual-energy X-ray absorptiometry was performed on the subjects at the initial evaluation and once yearly thereafter while on the treatment. RESULTS: The bone mineral density parameters for chronological age tended to decrease near the mean for the treatment period; however, they increased significantly for bone age excluding bone mineral apparent density. An increment of the BMI was not significant for the chronological age. CONCLUSIONS: Three-year treatment with GnRH agonist in central precocious puberty patients did not impair bone maturation. GnRH agonist could be effectively commenced in girls with precocious puberty from an early age.

Proteomic analyses of soybean root tips during germination.

Plant root systems form complex networks with the surrounding soil environment and are controlled by both internal and external factors. To better understand the function of root tips of soybean during germination, three proteomic techniques were used to analyze the protein profiles of root tip cells. Proteins were extracted from the root tips of 4-day-old soybean seedlings and analyzed using two-dimensional (2D) gel electrophoresis-based proteomics, SDS-gel based proteomics, and gel-free proteomics techniques. A total of 121, 862, and 341 proteins were identified in root tips using the 2D gel-based, SDS gel-based, and gel-free proteomic techniques, respectively. The proteins identified by 2D gel-based proteomic analysis were predominantly localized in the cytoplasm, whereas nuclear-localized proteins were most commonly identified by the SDS gel-based and gel-free proteomics techniques. Of the 862 proteins identified in the SDS gel-based proteomic analysis, 190 were protein synthesis-related proteins. Furthermore, 24 proteins identified using the 2D-gel based proteomic technique shifted between acidic and basic isoelectric points, and 2 proteins, heat shock protein 70.2 and AAA-type ATPase, displayed two different molecular weights at the same isoelectric point. Taken together, these results suggest that a number of proteins related to protein synthesis and modification are activated in the root tips of soybean seedlings during germination.

Nateglinide and acarbose for postprandial glucose control after optimizing fasting glucose with insulin glargine in patients with type 2 diabetes.

AIMS: Basal insulin treatment is frequently used in type 2 diabetes, but the successful control of postprandial glucose is challenging. We compared the effect of preferential postprandial glucose targeting drugs for postprandial glucose control after optimizing fasting glucose with basal insulin. METHODS: This study was performed in 58, insulin naïve type 2 diabetes. After fasting glucose was optimized by insulin glargine, nateglinide or acarbose was initiated and then crossed over after second wash out period. 75 g oral glucose tolerance test and 7 point self monitoring blood glucose for 3 days at the end of each period was performed. RESULTS: Both drugs effectively reduced postprandial glucose levels compared with the insulin glargine monotherapy. No significant differences were found between nateglinide and acarbose in terms of mean glucose level, standard deviation of glucose levels, mean average glucose excursion and average daily risk range. Homeostasis model analysis (HOMA)% ß, corrected insulin response and insulin-to-glucose ratio were significantly higher in the responder group compared with the non-responder. There was no episode of severe hypoglycemia. CONCLUSIONS: Nateglinide and acarbose are equally effective in type 2 diabetes for postprandial glucose excursions during basal insulin treatment. The markers of beta cell function might be used for predicting response. (Clinical trial reg. no. NCT 00437918, clinicaltrial.gov.).

The effect of chromium on rat insulinoma cells in high glucose conditions.

AIMS: it has been suggested that Chromium (Cr), one of the essential minerals, can be beneficial to type 2 diabetic patients because it lowers blood glucose levels by improving various steps in insulin action. A few studies reported that Cr might also have some beneficial effects in people with type 1 diabetes mellitus and in streptozotocin-treated rats, but direct beneficial effects of Cr on pancreatic beta cells have not been proven. We performed this study to determine whether Cr could have direct protective effects on INS-1 cells in high glucose conditions that mimic the actual diabetic state. MAIN METHODS: INS-1 cells were cultured for 48h in RPMI medium with 33mM glucose as the stress condition and 11mM glucose as a control. CrCl(3) was used to verify whether Cr could protect INS-1 cells from glucotoxic stress. Cell viability and apoptosis were evaluated by MTT assay and FACS. The level of insulin mRNA, by semi-quantitative RT-PCR, was significantly reduced at 33mM glucose concentration after 48h of incubation. KEY FINDINGS: cell viability was reduced by 50%, and 35% of the cells underwent apoptosis at the same culture condition. Addition of various concentrations of CrCl(3) to INS-1 cells in 33mM glucose for different durations of time did not reveal any beneficial effects on cell viability, degree of apoptosis, insulin mRNA levels, and glucose stimulated insulin secretion. SIGNIFICANCE: we could not find any evidence that Cr had direct beneficial effects on INS-1 cells in high glucose induced stress conditions.