Early Detection of Diabetic Kidney Disease with Biomarkers

Introduction

Over one third of diabetics will develop diabetic kidney disease (DKD) in their lifetime¹. Despite the large amount of diabetics suffering from DKD, current methods for measuring and tracking kidney function may not be specific enough for diabetic systems^2,3.

Part III of The Common Denominator eBook series examines the kidney complications caused by diabetes, and current research to improve the early detection of diabetic kidney disease with biomarkers.

The Filtration and Urinary Systems: An Overview

The body’s filtration and urinary systems have several key functions which include cleaning and removing waste products from the blood and recycling key nutrients.  The kidneys, ureters, bladder, and urethra make up these systems.

In order to achieve homeostasis, these highly specialized organs and muscles must work together properly.

Kidney Complications Caused by Diabetes

They kidneys recycle glucose and remove insulin from the blood, which helps to maintain energy homeostasis^8,9.  Kidney disease is the general term used for all of the different diseases, disorders, and damages that can occur within the kidneys⁵. Kidney disease that develops as a result of having diabetes is called diabetic kidney disease (DKD) or diabetic nephropathy (DN).

Having diabetes is a major risk factor for developing kidney damage^2,6,7.

Research on the Early Detection of Diabetic Kidney Disease with Biomarkers

Current methods for detecting kidney damage in diabetics may not be specific enough to accurately reflect kidney health^2,3.  There are several important kidney damage and disease biomarkers making appearances in diabetes research in an effort to improve the early detection of diabetic kidney disease.

Cystatin C

Cystatin C is a small cysteine proteinase produced in nearly every cell containing a nucleus in the human body. It is easily filtered out by the kidneys and levels can directly correlate with how well kidneys are filtering blood.^10,11,12

Neutrophil Gelatinase-Associated Lipocalin (NGAL)

NGAL is part of the innate immune system’s bacterial defense structure. It binds to iron in the presence of invading bacteria, preventing the bacteria from utilizing the body’s iron¹³. NGAL is also rapidly released into urine when the kidneys are damaged¹⁴.

Kidney Injury Molecule-1 (KIM-1)

KIM-1 is a type 1 transmembrane structural glycoprotein found in kidney epithelia cells and is released during regeneration^16,17. It is not detectable in healthy kidneys, making urinary KIM-1 a useful biomarker for detecting kidney damage^16,16,17.

Alpha-2-Macroglobulin (A2M)

A2M is one of the largest known plasma proteins acting as a protest inhibitor^18,19. Levels of A2M increase in blood if there is kidney damage²⁰.

Fetuin-A

Fetuin-A is a glycoprotein synthesized by the liver and secreted into the blood stream. It is involved in calcium metabolism and bone formation. Levels of fetuin-A may be associated with kidney failure²¹.

Summary

Researchers have been working diligently to better understand how to improve the early detection of diabetic kidney disease with biomarkers. Using kidney damage and disease biomarkers to research diabetes can continue to further the understanding of both diseases while also improving the lives of thousands.

The Common Denominator is a three part eBook series reviewing diabetes, cardiovascular and kidney complications associated with diabetes, as well as important biomarkers that have become useful in researching these areas.

Part III: Detecting Kidney Damage – An Investigation into Diabetic Nephropathy reviews the kidney complications of diabetes, and how kidney damage and  disease biomarkers are emerging as useful tools in diabetes research.

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References

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