関: glycated、Maillard reaction、saccharification、saccharify

WordNet

convert into a simple soluble fermentable sugar by hydrolyzing a sugar derivative or complex carbohydrate

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/04/22 20:12:15」(JST)

wiki en

Glycation (sometimes called non-enzymatic glycosylation) is the result of the typically covalent bonding of a protein or lipid molecule with a sugar molecule, such as fructose or glucose, without the controlling action of an enzyme. All blood sugars are reducing molecules. Glycation may occur either inside the body (endogenous glycation) or outside the body (exogenous glycation). Enzyme-controlled addition of sugars to protein or lipid molecules is termed glycosylation; glycation is a haphazard process that impairs the functioning of biomolecules, whereas glycosylation occurs at defined sites on the target molecule and is required in order for the molecule to function. Much of the early laboratory research work on fructose glycations used inaccurate assay techniques that led to drastic underestimation of the importance of fructose in glycation.^[1]

Exogenous

Exogenous, meaning outside the body, may also be referred to as dietary or pre-formed. Exogenous glycations and Advanced Glycation Endproducts (AGEs) are formed when sugars are cooked with proteins or fats. Temperatures over 120°C (~248°F) greatly accelerate the reactions, but lower temperatures with longer cooking times also promote their formation.^{[citation needed]}

These compounds are absorbed by the body during digestion with about 10% efficiency.^{[citation needed]} Browning reactions (usually Maillard type reactions) are evidence of pre-formed glycations. Indeed, sugar is often added to products such as french fries and baked goods to enhance browning.^{[citation needed]} Glycation may also contribute to the formation of acrylamide,^[2] a potential carcinogen, during cooking. Until recently, it was thought that exogenous glycations and AGEs were negligible contributors to inflammation and disease states, but recent work has shown that they are important.^[3]

Food manufacturers have added AGEs to foods, especially in the last 50 years, as flavor enhancers and colorants to improve appearance.^[4] Foods with significant browning, caramelization, or directly added preformed AGEs can be high in these compounds.^[5] A very partial listing of foods with very high exogenous AGEs includes donuts, barbecued meats, cake, and dark colored soda pop.^[6]

Endogenous

Endogenous glycations occur mainly in the bloodstream to a small proportion of the absorbed simple sugars: glucose, fructose, and galactose. It appears that fructose and galactose have approximately ten times the glycation activity of glucose, the primary body fuel.^[7] Glycation is the first step in the evolution of these molecules through a complex series of very slow reactions in the body known as Amadori reactions, Schiff base reactions, and Maillard reactions; which lead to advanced glycation endproducts (AGEs). Some AGEs are benign, but others are more reactive than the sugars they are derived from, and are implicated in many age-related chronic diseases such as cardiovascular diseases (the endothelium, fibrinogen, and collagen are damaged), Alzheimer's disease (amyloid proteins are side-products of the reactions progressing to AGEs),^[8]^[9] cancer (acrylamide and other side-products are released), peripheral neuropathy (the myelin is attacked), and other sensory losses such as deafness (due to demyelination). This range of diseases is the result of the very basic level at which glycations interfere with molecular and cellular functioning throughout the body and the release of highly oxidizing side-products such as hydrogen peroxide.

Long-lived cells (such as nerves and different types of brain cell), long-lasting proteins (such as crystallins of the lens and cornea), and DNA may accumulate substantial damage over time. Cells such as the retina cells in the eyes, and beta cells (insulin-producing) in the pancreas are also at high risk of damage^{[citation needed]}. Damage by glycation results in stiffening of the collagen in the blood vessel walls, leading to high blood pressure, especially in diabetes.^[10] Glycations also cause weakening of the collagen in the blood vessel walls^{[citation needed]}, which may lead to micro- or macro-aneurisms; this may cause strokes if in the brain.

Red blood cells have a consistent lifespan of 120 days and are easily accessible for measurement of recent increased presence of glycating product. This fact is used in monitoring blood sugar control in diabetes by monitoring the glycated hemoglobin level, also known as HbA1c.

References

^ Ahmed N, Furth AJ (July 1992). "Failure of common glycation assays to detect glycation by fructose". Clin. Chem. 38 (7): 1301–3. PMID 1623595.
^ Stadler RH, Blank I, Varga N, et al. (October 2002). "Acrylamide from Maillard reaction products". Nature 419 (6906): 449–50. Bibcode:2002Natur.419..449S. doi:10.1038/419449a. PMID 12368845.
^ Vlassara H (June 2005). "Advanced glycation in health and disease: role of the modern environment". Annals of the New York Academy of Sciences 1043 (1): 452–60. Bibcode:2005NYASA1043..452V. doi:10.1196/annals.1333.051. PMID 16037266.
^ Peppa, Melpomeni; Uribarri, J.; Vlassara, H.; et al. (2003). "Glucose, Advanced Glycation End Products, and Diabetes Complications: What Is New and What Works" (PDF). Clinical Diabetes 21 (4): 186. doi:10.2337/diaclin.21.4.186. Archived from the original (PDF) on October 23, 2006.
^ Koschinsky T, He CJ, Mitsuhashi T, et al. (June 1997). "Orally absorbed reactive glycation products (glycotoxins): an environmental risk factor in diabetic nephropathy". Proc. Natl. Acad. Sci. U.S.A. 94 (12): 6474–9. Bibcode:1997PNAS...94.6474K. doi:10.1073/pnas.94.12.6474. PMC: 21074. PMID 9177242.
^ ^{[citation needed]}
^ McPherson JD, Shilton BH, Walton DJ (March 1988). "Role of fructose in glycation and cross-linking of proteins". Biochemistry 27 (6): 1901–7. doi:10.1021/bi00406a016. PMID 3132203.
^ Münch, Gerald; et al. (27 February 1997). "Influence of advanced glycation end-products and AGE-inhibitors on nucleation-dependent polymerization of β-amyloid peptide". Biochimica et Biophysica Acta 1360 (1): 17–29. doi:10.1016/S0925-4439(96)00062-2. PMID 9061036.
^ Munch, G; Deuther-Conrad W; Gasic-Milenkovic J. (2002). "Glycoxidative stress creates a vicious cycle of neurodegeneration in Alzheimer's disease--a target for neuroprotective treatment strategies?". J Neural Transm Suppl. 62 (62): 303–307. doi:10.1007/978-3-7091-6139-5_28. PMID 12456073.
^ Soldatos, G.; Cooper ME (Dec 2006). "Advanced glycation end products and vascular structure and function". Curr Hypertens Rep 8 (6): 472–478. doi:10.1007/s11906-006-0025-8. PMID 17087858.

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 眼の待機手術に対する麻酔 anesthesia for elective eye surgery
2. Anesthesia for elective spine surgery in adults
3. 慢性閉塞性肺疾患（COPD）における抗コリン療法の役割 role of anticholinergic therapy in copd
4. 緩和ケア：人生最後の数時間 palliative care the last hours and days of life
5. 原発性局所多汗症 primary focal hyperhidrosis

English Journal

Glycation and transglutaminase mediated glycosylation of fish gelatin peptides with glucosamine enhance bioactivity.

Hong PK, Gottardi D, Ndagijimana M, Betti M.SourceDepartment of Agricultural, Food and Nutritional Science (AFNS), Faculty of Agricultural, Life and Environmental Sciences (ALES), University of Alberta, 4-10 Agriculture/Forestry Centre, Edmonton, Alberta T6G 2P5, Canada.
Food chemistry.Food Chem.2014 Jan 1;142:285-93. doi: 10.1016/j.foodchem.2013.07.045. Epub 2013 Jul 19.
A mixture of novel glycopeptides from glycosylation between cold water fish skin gelatin hydrolysates and glucosamine (GlcN) via transglutaminase (TGase), as well as glycation between fish gelatin hydrolysate and GlcN were identified by their pattern of molecular distribution using MALDI-TOF-MS. Gly
PMID 24001843

Tauroursodeoxycholic acid protects retinal neural cells from cell death induced by prolonged exposure to elevated glucose.

Gaspar JM, Martins A, Cruz R, Rodrigues CM, Ambrósio AF, Santiago AR.SourceCenter of Ophthalmology and Vision Sciences, Institute of Biomedical Research in Light and Image (IBILI), Faculty of Medicine, University of Coimbra, 3004-548 Coimbra, Portugal; Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal.
Neuroscience.Neuroscience.2013 Dec 3;253:380-8. doi: 10.1016/j.neuroscience.2013.08.053. Epub 2013 Sep 5.
Diabetic retinopathy is one of the most frequent causes of blindness in adults in the Western countries. Although diabetic retinopathy is considered a vascular disease, several reports demonstrate that retinal neurons are also affected, leading to vision loss. Tauroursodeoxycholic acid (TUDCA), an e
PMID 24012838

Senescence-dependent impact of anti-RAGE antibody on endotoxemic liver failure.

Kuhla A, Hauke M, Sempert K, Vollmar B, Zechner D.SourceInstitute for Experimental Surgery, University of Rostock, Schillingallee 69a, 18057, Rostock, Germany.
Age (Dordrecht, Netherlands).Age (Dordr).2013 Dec;35(6):2153-63. doi: 10.1007/s11357-012-9506-7. Epub 2013 Jan 15.
Aging often restricts the capacity of the immune system. Endotoxemia is characterized by an immune response initiated by a group of pattern recognition receptors including the receptor for advanced glycation end products (RAGE). The aim of this study was to clarify to which extent RAGE and its signa
PMID 23319363

Japanese Journal

老化物質AGEによる脱毛機構 (特集育毛・脱毛・白髪のメカニズム)

Fragrance journal = フレグランスジャーナル 44(1), 34-37, 2016-01
NAID 40020712004

Two new prenylflavonoids from Epimedii Herba and their inhibitory effects on advanced glycation end-products

Journal of natural medicines 70(2), 290-295, 2016
NAID 40020758329

Plasma Levels of Receptor for Advanced Glycation End-Products and High-Mobility Group Box 1 in Patients With Pulmonary Hypertension

International Heart Journal advpub(0), 2016
NAID 130005132870

Related Pictures

★リンクテーブル★

リンク元	「マイヤール反応」「グリケーション」「Maillard reaction」「糖化」「glycated」
拡張検索	「advanced glycation end product」「receptor for advanced glycation end products」