Because advanced glycation end product (AGE) inhibitors such as pyridoxamine significantly inhibit the development of retinopathy and neuropathy in the streptozotocin-induced diabetic rat, treatment with AGE inhibitors is believed to be a potential strategy for the prevention of lifestyle-related diseases such as diabetic complications. A crude extract of Astragali Radix (AR; roots of Astragalus membranaceus ) inhibits the formation of N(epsilon)-(carboxymethyl)lysine (CML) and pentosidine during the incubation of bovine serum albumin with ribose. In the present study, compounds were isolated from AR that prevented CML and pentosidine formation. Astragalosides significantly inhibited the formation of both CML and pentosidine, and astragaloside V had the strongest inhibitory effect among all if the isolated compounds. These data suggest that AR and astragalosides may be a potentially useful strategy for the prevention of clinical diabetic complications by inhibiting AGEs.

Polyclonal and monoclonal antibodies have been widely applied to demonstrate the presence of advanced glycation end products (AGEs) in vivo. However, our previous study showed that monoclonal anti-AGE antibody (6D12) and polyclonal anti-N epsilon-(carboxymethyl)lysine (CML) antibody recognize not only CML but also N epsilon-(carboxyethyl)lysine (CEL), thus indicating that we should pay attention to the specificity of the antibodies. As a result, we prepared specific monoclonal antibodies against CML, CEL, N omega-(carboxymethyl)arginine (CMA), and S-(carboxymethyl)cysteine (CMC). Our immunochemical study using anti-CMA antibody demonstrated that the CMA content increased in a time-dependent manner when collagen was incubated with glucose, indicating that immunological quantification using the specific antibody is especially useful for measuring an acid-labile AGE structure, such as CMA. Monoclonal antibody is also applied to identify a novel biological marker in pathological lesions. We prepared antibody libraries against proteins modified with aldehydes, such as glyoxal, methylglyoxal, and glycolaldehyde (GA), and one antibody, GA5, which specifically reacts with the GA-modified protein that is recognized in human atherosclerotic lesions. Following successive high-performance liquid chromatography purification, the GA5-reactive compound was isolated and its chemical structure was found to be 3-hydroxy-4-hydroxymethyl-1-(5-amino-5-carboxypentyl) pyridinium cation, which was named GA-pyridine. Taken together, these results demonstrate that a specific antibody is a powerful tool for analyzing novel biomarkers, formation pathways, and the efficacy of AGE inhibitors.

Since pyridoxamine, which traps intermediates in the Maillard reaction and lipid peroxidation reaction, significantly inhibits the development of retinopathy and neuropathy in the streptozotocin-induced diabetic rat, treatment with advanced glycation end product inhibitors and antioxidants may be a potential strategy for the prevention of clinical diabetic complications. However, the paradoxical effect of green tea has been reported; although plasma hydroperoxide levels were ameliorated, the level of N epsilon-(carboxyethyl)lysine (CML) in tendon and plasma was increased by the oral administration of green tea to diabetic rats. In the present study, we measured the effect of natural compounds on CML formation by enzyme-linked immunosorbent assay. A significant amount of CML was observed when bovine serum albumin was incubated with ribose for 7 days. Under the same conditions, natural compounds, such as desgalactotigonin, showed inhibitory effects, whereas quercetin and acteoside enhanced CML formation, indicating that natural compounds contain both inhibitors and enhancers for CML formation.

In this study, we focus on areas outside Residential Promotion Area, targeting Area-divided local cities making Urban Facility Location Plan, and aims to clarify the making process of the plan and to give suggestions on how to designate Residential Promotion Area in the future.We classify the target cities using the ratio of the inside and outside of Residential Promotion Area to both the original Urbanization Promotion Area and the extended one. Then, we analyze the spatial characteristics from the viewpoint of public transport, infrastructure development and population density, and select 6 detailed target cities.From the analysis and interview survey, we find the following points. 1) Residential Promotion Area should be designated after selecting from various viewpoints centering one index.2) It should not include places where there is a high risk of disaster, and it is desirable to designate the area based on the location of existing urban areas and the status of land use.