Intracellular Accumulation of Advanced Glycation End Products Induces Osteoblast Apoptosis Via Endoplasmic Reticulum Stress.

Osteoporosis is an aging-associated disease that is attributed to excessive osteoblast apoptosis. It is known that the accumulation of advanced glycation end products (AGEs) in bone extracellular matrix deteriorates osteoblast functions. However, little is known about the interaction between intracellular AGE accumulation and the induction of osteoblast apoptosis.

Roxb. and lutein ameliorate cataract in type 1 diabetic rats.

Roxb. is an annual aquatic grass of the citrus family. Although its hot water extract displays antioxidative activity , little is known about its biological effectiveness.

Glucoselysine is derived from fructose and accumulates in the eye lens of diabetic rats.

Prolonged hyperglycemia generates advanced glycation end-products (AGEs), which are believed to be involved in the pathogenesis of diabetic complications. In the present study, we developed a polyclonal antibody against fructose-modified proteins (Fru-P antibody) and identified its epitope as glucoselysine (GL) by NMR and LC-electrospray ionization (ESI)- quadrupole TOF (QTOF) analyses and evaluated its potential role in diabetes sequelae. Although the molecular weight of GL was identical to that of fructoselysine (FL), GL was distinguishable from FL because GL was resistant to acid hydrolysis, which converted all of the FLs to furosine.

-(Carboxymethyl)arginine Is One of the Dominant Advanced Glycation End Products in Glycated Collagens and Mouse Tissues.

Advanced glycation end products (AGEs) accumulate in proteins during aging in humans. In particular, the AGE structure -(carboxymethyl)arginine (CMA) is produced by oxidation in glycated collagen, accounting for one of the major proteins detected in biological samples. In this study, we investigated the mechanism by which CMA is generated in collagen and detected CMA in collagen-rich tissues.

[Preventive Effects of Aphanothece sacrum on Diabetic Cataracts].

Approximately 20% of diabetic patients develop diabetic cataracts. As lens proteins are known to be only slightly metabolized during the lifetime, cataracts are difficult to recover from once they have progressed. Therefore, the daily intake of natural compounds would be an important strategy for the prevention of diabetic cataracts.

Aphanothece sacrum (Sur.) Okada Prevents Cataractogenesis in Type 1 Diabetic Mice.

Aphanothece sacrum (Sur.) Okada is a species of cyanobacteria found in Japan. Although it has been used in local cuisine in Kyushu, Japan, for 250 y, little is known about its beneficial effect as food.

Contribution of methylglyoxal to delayed healing of bone injury in diabetes.

Patients with diabetes are vulnerable to delayed bone fracture healing or pseudoarthrosis. Chronic sustained hyperglycemia, reactive intermediate derivatives of glucose metabolism, such as methylglyoxal (MGO), and advanced glycation end‑products (AGEs) are implicated in diabetic complications. In the present study, it was examined whether MGO is able to cause disturbed bone healing in diabetes.

N-(carboxymethyl)lysine Concentration in Debris from Carotid Artery Stenting Correlates Independently with Signal Intensity on T1-Weighted Black-Blood Magnetic Resonance Images.

Background And Purpose: Because magnetic resonance imaging (MRI) focuses on the morphological characteristics of carotid artery plaques, its diagnostic value with respect to plaque vulnerability is limited. We examined the correlation between N-(carboxymethyl)lysine (CML), a main chemical structure of advanced glycation end-products, and the vulnerability of plaques visualized on MRI scans.

Materials And Methods: We enrolled 43 patients who had undergone carotid artery stenting (CAS) for carotid artery stenosis; all underwent MRI studies, including black-blood MRI and diffusion-weighted imaging (DWI).

Antibody-based detection of advanced glycation end-products: promises vs. limitations.

Advanced glycation end-products (AGEs) of the Maillard reaction were originally measured according to their fluorescent and browning properties. A subsequent study with instrumental analyses such as high-performance liquid chromatography and gas chromatography mass spectrometry more clearly demonstrated the involvement of each AGE structure in pathological conditions. Furthermore, immunochemical methods have also been developed to clarify the localization of AGEs in tissues and measurement of AGEs in multiple clinical samples.

High serum level of methylglyoxal-derived AGE, Nδ-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine, independently relates to renal dysfunction.

Background: The dicarbonyl methylglyoxal reacts primarily with arginine residues to form advanced glycation end products, including Nδ-(5-hydro-5-methyl-4 -imidazolone-2-yl)-ornithine (MG-H1), which are risk factors for not only diabetic complications but also lifestyle-related disease including renal dysfunction. However, the data on serum level and clinical significance of this substance in chronic kidney disease are limited.

Methods: Serum levels of MG-H1 and Nε-(carboxymethyl) lysine (CML) in 50 patients with renal dysfunction were measured by liquid chromatography/triple-quadruple mass spectrometry.

Salacia chinensis L. extract ameliorates abnormal glucose metabolism and improves the bone strength and accumulation of AGEs in type 1 diabetic rats.

Although extracts of the roots and stems of Salacia chinensis have been used in folk medicines for chronic diseases such as rheumatism, irregular menstruation, asthma and diabetes mellitus, little is known about the mechanism by which Salacia chinensis extract (SCE) ameliorates these diseases. To clarify whether SCE ameliorates the progression of lifestyle-related diseases, the inhibitory effect of SCE on the formation of advanced glycation end products (AGEs) was analyzed in a rat model of streptozotocin-induced diabetes. Although the oral administration of SCE did not ameliorate the diabetes-induced decrease in body weight, it ameliorated the increase in glycoalbumin levels in diabetic rats.

Eucommia ulmoides extracts prevent the formation of advanced glycation end products.

Proteins non-enzymatically react with reducing sugars to form advanced glycation end-products (AGEs), resulting in the induction of protein denaturation. Because the levels of AGE increase with age and are elevated in age-related diseases, such as diabetes and atherosclerosis, the intake of compound(s) that inhibit the formation of AGEs by daily meal may represent a potential strategy for preventing age-related diseases. In this study, we measured the inhibitory effects of several Eucommia ulmoides extracts on the formation of AGEs, N(ε)-(carboxymethyl)lysine (CML) and N(ω)-(carboxymethyl)arginine (CMA).

Non-invasive measurement of skin autofluorescence to evaluate diabetic complications.

Although the accumulation of advanced glycation end-products (AGEs) of the Maillard reaction in our body is reported to increase with aging and is enhanced by the pathogenesis of lifestyle-related diseases such as diabetes, routine measurement of AGEs is not applied to regular clinical diagnoses due to the lack of conventional and reliable techniques for AGEs analyses. In the present study, a non-invasive AGEs measuring device was developed and the association between skin AGEs and diabetic complications was evaluated. To clarify the association between the duration of hyperglycemia and accumulation of skin fluorophores, diabetes was induced in mice by streptozotocin.

Soft-shelled turtle eggs inhibit the formation of AGEs in the serum and skin of diabetic rats.

Although soft-shelled turtle eggs (STE) have been used as a folk medicine for revitalization and the prevention of lifestyle-related diseases, the scientific evidence to support the use of STE in this manner is scarce. To clarify the physiological evidence, STE was administered to diabetic rats and the inhibitory effects on the formation of advanced glycation end-products (AGEs), which are known to increase with the progression of lifestyle-related diseases, were examined. STE and citric acid were administered to diabetic rats for 3 months, and serum N (ε)-(carboxymethyl)lysine (CML) contents were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Detection of AGEs as markers for carbohydrate metabolism and protein denaturation.

Approximately 100 years have passed since the Maillard reaction was first reported in the field of food chemistry as a condensation reaction between reducing sugars and amino acids. This reaction is thought to progress slowly primarily from glucose with proteins in vivo. An early-stage product, called the "Amadori product", is converted into advanced glycation end products.

Inhibition of AGEs formation by natural products.

Since advanced glycation end-products (AGEs) inhibitors such as benfotiamine, pyridoxamine and aminoguanidine significantly inhibit the development of retinopathy and neuropathy in streptozotocin-induced diabetic rats, treatment with AGEs inhibitors is believed to be a potential strategy for preventing lifestyle-related diseases such as diabetic complications and atherosclerosis. Furthermore, preventive medicine is the most important approach to preventing lifestyle-related diseases, and improving daily nutritional intake is thought to prevent the pathogenesis of such diseases. Therefore, AGEs inhibitors that can be obtained from daily meals are preferred to prescribed drugs.

Changes in electronic structure upon lithium insertion into Fe2(SO4)3 and Fe2(MoO4)3 investigated by X-ray absorption spectroscopy.

Changes in electronic structure upon electrochemical lithium insertion into two iron compounds, namely, rhombohedral Fe2(SO4)3 with a NASICON-type structure and monoclinic Fe2(MoO4)3, were investigated using X-ray absorption spectroscopy (XAS). Fe K-edge and L(III)- and L(II)-edge XAS revealed that the rearrangement of Fe d electrons or rehybridization of Fe d-O p bonding took place accompanied by the reduction of Fe ions upon Li insertion for both samples and that a larger change in spectra was observed in Fe2(SO4)3. In addition, the changes in the electronic structure of the polyanion units XO4(2-) (X = S or Mo) after Li insertion were also investigated by O K-edge and S K-edge or Mo L(III)-edge XAS.

Changes in electronic structure upon Li insertion reaction of monoclinic Li3Fe2(PO4)3.

The electrochemical lithium insertion reaction of monoclinic Li(3)Fe(2)(PO(4))(3) as cathode materials of lithium-ion batteries was investigated from the viewpoint of the electronic structure around Fe and the polyanion unit (PO(4)). Fe K-edge and L(III,II)-edge XAS measurements revealed that Fe(3+) was reduced to Fe(2+) upon Li insertion. In addition, O K-edge and P K-edge XAS also showed spectral changes upon Li insertion, which corresponded to changes in the electronic structure of the PO(4) polyanion unit.