中老年人飲食糖化終產物與飲食品質及骨骼肌肉健康之相關性

形成糖化終產物(advanced glycation end-products, AGEs)的最典型的途徑為還原醣與蛋白質、脂質或核酸的胺基之梅納反應，再經過一連串的化學反應不可逆的產生AGEs。內源性AGEs為人體正常代謝過程中所產生，而飲食是體內AGEs的主要來源；飲食糖化終產物(dietary advanced glycation end-product, dAGE)的多寡受到食物的種類及烹調加工方式等因素影響：富含蛋白質和脂肪的動物性食物及乾熱法烹調有較多dAGE。AGEs與細胞外基質的蛋白質共價交聯會影響其結構及功能；若AGEs與細胞膜上AGEs受體結合則使氧化壓力及發炎反應增加，這兩種作用皆可能損害骨骼肌肉健康，引起骨質疏鬆及肌少症。本研究目的為分析dAGE攝取量與骨骼肌肉健康之關係；另一方面，飲食品質評分可用於評估飲食攝取與建議量的符合程度，本研究亦探討飲食品質與dAGE的關聯性。本研究分析了92位(44位男性及48位女性)具自主行動能力的中老年人之橫斷性資料，使用雙能量X光吸收儀(dual-energy X-ray absorptiometry, DXA)檢測個案體組成及骨密度，並測量肌少症功能性指標，利用24小時飲食回憶紀錄計算dAGE攝取量(kU/天)以及全面飲食指標修訂版(Overall Dietary Index Revised, ODI-R)評分；為使dAGE獨立於熱量，本研究以熱量密度呈現dAGE攝取量(kU/kcal)並進行分組，以中位數3.68 (kU/kcal)為切點分成高低兩組進行比較。結果顯示dAGE平均攝取量為4.85±3.34kU/kcal，ODI-R平均64.31±9.98分，分別有26%及25%個案符合骨質疏鬆及肌少症定義。dAGE高低兩組間飲食品質、體組成及肌少症功能性指標不具顯著差異，而高dAGE組全身骨密度及骨礦物量顯著較低(p<0.05)，飲食攝取方面觀察到高dAGE組碳水化合物攝取較少(p=0.0002)、脂質(p=0.0011)及蛋白質(p=0.0261)攝取較多。根據骨骼或肌肉健康狀態分組後，各組間之dAGE亦無觀察到顯著差異。相關分析發現，dAGE與年齡及蔬果攝取呈負相關，與肉類及豆類攝取呈正相關(p<0.05)，但與ODI-R、全身、腰椎和股骨頸之骨密度及各項肌少症功能性指標無關。迴歸分析顯示，dAGE與骨質疏鬆或肌少症不具顯著關聯性。本橫斷式研究分析觀察到dAGE與年齡、蔬菜、水果、豆類及肉類攝取有關，與ODI-R、骨密度及肌肉質量或功能無關。未來可透過縱向研究更深入探討dAGE對骨骼肌肉健康的影響，以國人飲食為基礎建立dAGE資料庫，並設計更完善的飲食品質評分標準及飲食頻率問卷，更準確評估dAGE與飲食品質及各類食物攝取之關係。

The most typical way to form advanced glycation end-products (AGEs) involves the Maillard reaction. Reducing sugars first undergo condensation reaction with amine groups of proteins, lipids, or nucleic acids, followed by a series of irreversible chemical reactions that result in the formation of AGEs. Endogenous AGEs are produced during normal metabolic processes, whereas diet is the primary source of exogenous AGEs in human body. The amount of dietary AGEs (dAGE) depends on various factors, including the type of food and cooking/ processing methods. Both animal-based foods rich in proteins and fats and foods prepared using dry heat cooking methods contain higher levels of dAGE. The covalent cross-linking of AGEs with extracellular matrix proteins can alter their structure and function. In addition, the binding of AGEs to the membrane receptor for AGEs can increase oxidative stress and inflammation. These two effects exerted by AGEs may impair musculoskeletal health, thereby increasing the risk of developing osteoporosis and sarcopenia. The purpose of this study was to analyze the correlation between dAGE and musculoskeletal health. Additionally, the association between the dietary quality, which was assessed by evaluating the dietary quality scores, and dAGE intake was also explored. This study analyzed cross-sectional data from 92 middle-aged and elderly (44 men and 48 women) with independent mobility. Body composition and bone mass of the participants were measured using dual-energy X-ray absorptiometry (DXA). Additionally, functional indicators of sarcopenia were also assessed. dAGE intake and the score of overall dietary index revised (ODI-R) were calculated based on 24-hour dietary recall data. dAGE was expressed as energy density (kU/kcal) to ensure it was independent of total energy intake, and the participants were grouped as high and low dAGE intake groups for comparison based on a median cutoff of 3.68 kU/kcal.The results show that the average dAGE intake was 4.85±3.34 kU/kcal and the mean ODI-R score was 64.31±9.98. Twenty-six percent and 25% of participants met the criteria of osteoporosis and sarcopenia, respectively. There were no significant differences in dietary quality, body composition and functional indicators of sarcopenia between high and low dAGE intake groups. The total body bone mineral content and density, however, were significantly lower in the high dAGE intake group (p<0.05). In terms of dietary intake, the high dAGE group consumed less carbohydrates (p=0.0002) and more fat (p=0.0011) and protein (p=0.0261). After grouping by bone or muscle health status, no significant differences in dAGE intake were observed between groups. In the correlation analysis, dAGE was negatively correlated with age, vegetable and fruit intake, and positively correlated with meat and soy intake (p<0.05). However, ODI-R, bone mineral density at total body, lumber spine and femoral neck, as well as functional indicators of sarcopenia showed no significant correlation with dAGE. Moreover, regression analysis did not reveal any significant association between dAGEs and osteoporosis or sarcopenia.This cross-sectional study revealed that dAGE was related to age, vegetable, and meat intake, but not to ODI-R, bone mineral density or muscle mass or function. Future longitudinal studies are required to explore the impact of dAGE on musculoskeletal health. Moreover, it is necessary to establish a dAGE database that reflects the dietary habits of Taiwanese population. In addition, a more comprehensive dietary quality scoring system and improved food frequency questionnaires are essential for more accurately assess the relationships between dAGE, dietary quality, and the intake of various food groups.