by Glycated albumin (GA) refers to albumin that has been bonded with sugar molecules through a non-enzymatic glycation reaction. Albumin is a protein produced by the liver and is the most abundant protein in human blood plasma, making up about 50% of human serum protein. Normally, albumin transports hormones, fatty acids and other substances in the bloodstream. However, under conditions of elevated blood glucose such as in diabetes, excess blood glucose can attach to albumin through a non-enzymatic reaction called glycation. This glycated form of albumin is known as glycated albumin.
Formation and Accumulation of Glycated Albumin
Glycated Albumin Assay reaction between glucose and albumin occurs spontaneously without the involvement of enzymes. Studies have found that the glycation rate of albumin is 10 to 20 times faster than glycation of hemoglobin. Due to its short half-life of 14-20 days in the body, the levels of glycated albumin accurately reflect blood glucose control over the past 2-3 weeks. In contrast, glycated hemoglobin (HbA1c) provides information on average blood glucose levels over the past 2-3 months as albumin has a lifespan of around 120 days in red blood cells. Therefore, the accumulation and levels of glycated albumin are more closely associated with recent glycemic control compared to glycated hemoglobin.
Clinical Utility of Glycated Albumin Assay
Several clinical benefits of glycated albumin testing have been highlighted:
– It provides a more accurate assessment of short-term glycemic control over 2-3 weeks compared to HbA1c which represents glycemic control over 2-3 months. This makes glycated albumin a valuable tool for intensifying treatment in patients with poorly controlled diabetes.
– Glycated Albumin Assay are less affected by factors such as anemia, hemoglobinopathies and abnormalities in red blood cell turnover. These medical conditions can impact HbA1c levels leading to inaccuracies in glycemic monitoring.
– For patients on hemodialysis or with renal failure, glycated albumin may be a more reliable biomarker than HbA1c since renal clearance affects albumin metabolism more than hemoglobin.
– In conditions affecting red blood cell lifespan such as blood loss or transfusions, glycated albumin testing experiences fewer interferences than HbA1c.
– GA levels have been shown to better predict the risk of diabetes complications like microvascular diseases compared to HbA1c alone. Combined testing of both may enhance risk assessments.
– Monitoring changes in glycated albumin in response to treatment provides valuable information on treatment efficacy in a shorter time frame. This allows timely interventions to optimize glycemic control.
Measurement Methods for Glycated Albumin
Several methods are employed to quantify glycated albumin levels in blood samples:
– Enzyme-linked lectin assay (ELLA/ECLA): Involves using lectins (sugar-binding proteins) to selectively recognize and quantify the glycated portion of albumin. This method is currently considered the gold standard.
– Boronate affinity chromatography: Uses boronic acid to selectively bind glycated albumin which is then quantified colorimetrically or spectrophotometrically.
– Immunoassay techniques: Employ monoclonal or polyclonal antibodies that selectively target the glycated albumin epitope. Examples include ELISA, turbidimetry and nephelometry methods.
– Colorimetric/spectrophotometric assays: Detect changes in absorbance properties after reaction of glycated albumin with probes like fructosamine or commercially available glycated albumin-specific dyes.
Point-of-care instruments have been developed to enable rapid glycated albumin results suitable for clinical and ambulatory settings using whole blood samples. Ongoing research continues to improve glycated albumin testing methods.
Clinical Significance and Future Directions
growing evidence suggests that glycated albumin may serve as a more suitable marker than HbA1c for monitoring recent glycemic control in various clinical situations. Its utility extends to diabetes management, risk assessments, treatment monitoring and evaluation of novel anti-hyperglycemic agents. Larger prospective studies are still needed to further validate its clinical significance. Standardizing commercially available glycated albumin assays also requires work to enable wider clinical adoption. Overall, incorporation of glycated albumin into routine practice holds promise to enhance glycemic management and diabetes care outcomes.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
