What is NGAL?

NGAL(Neutrophil Gelatinase-Associated Lipocalin), a 25 kDa protein, is a highly sensitive marker of acute kidney injury and has been found to be expressed in different human tissues such as uterus, prostate, lungs, trachea, stomach, colon and kidneys.NGAL is a sensitive marker of renal tubular injury.Generally, in the kidneys, NGAL is mainly secreted by the Hunter's collaterals and distal tubules, and it is almost entirely reabsorbed in the proximal tubules. Therefore, NGAL can only be detected in trace amounts in normal subjects.

Once the renal structure and function have been pathologically altered, NGAL plays a repairing role, preventing the attack of inflammatory cells through apoptosis and metabolism of tubular neutrophils (a defence compensatory mechanism), secreting NGAL in large quantities in the thick segment of the ascending tubular branch and releasing it into the systemic blood circulation, so that a high level of NGAL can be detected in urine and blood, and the appealing pathophysiological process has already appeared in the early stage of renal damage.

NGAL has powerful functions and has been implicated in inflammation, embryonic development, immune response, chemotaxis, signal transduction, and a variety of tumourigenesis and developmental processes, in addition to its function as a member of the apo family that binds and transports hydrophobic small molecules.NGAL is anti-inflammatory, anti-inflammatory, and promotes renal progenitor cell differentiation to early renal tubular epithelial cells.

NGAL can be micro-expressed in a variety of tissues such as heart, kidney, liver, pancreas, prostate and epithelial cells, and is involved in pathophysiological processes of the organism. In addition to various renal diseases, NGAL protein is also associated with metabolic diseases, cardiovascular and cerebrovascular diseases, inflammatory reactions and tumours to varying degrees!

Clinical application of NGAL

Normally low levels of NGAL are expressed in multiple organs such as liver, kidney, mammary gland, prostate, etc. In AKI, it is significantly overexpressed in the distal renal tubules and excreted in the urine, and the urinary level of NGAL rises 2-3h after the onset of AKI, and reaches a peak at 6h.

Specific clinical applications of NGAL are shown below:

① NGAL is an early sensitive and specific biomarker of Acute Kidney Injury (AKI). At the onset of AKI, whole blood and urine NGAL concentrations usually increase rapidly and are most pronounced at 2 h. Therefore, NGAL has high sensitivity, strong specificity and high accuracy in early AKI detection.

② NGAL levels can be an important indicator for the occurrence of acute kidney injury (AKI) and for determining prognosis.

③ Plasma and urine NGAL levels are significantly higher in patients with AKI and positively correlated with Scr.

④ Increasing the detection of NGAL levels in AKI patients is beneficial to early detection and treatment, which is important for improving the survival rate of AKI patients and protecting renal function.

⑤ Detection of NGAL levels allows early detection, diagnosis and treatment of hypertensive kidney damage in pregnancy.

⑥ NGAL is closely related to the degree of damage in early diabetic nephropathy (EDN) and is an important dynamic monitor of the development of diabetic kidney disease (DKD).

⑦ NGAL is a high-quality biomarker for lupus nephritis (LN).

⑧ NGAL can be used to assess the extent of kidney injury in CKD patients and is an independent predictor of the risk of CKD progression.

Factors affecting NGAL

Increased NGAL levels may be due to:

AKI

(NGAL is expressed in large quantities by the kidneys and released into the urine and plasma when ischaemic or nephrotoxic renal injury occurs as a result of diseases such as drug side-effects, severe renal infections, and tumours of the kidneys or surrounding tissues)

DKD

(Damage to the blood vessels of the kidneys leads to diabetic nephropathy, with varying degrees of damage to kidney tissue cells)

CKD

(Chronic nephritis occurs when there is chronic glomerular disease over a long period of time; elevated NGAL levels may be more pronounced in acute episodes of chronic nephritis)

Hyperglycaemia, hyperlipidaemia

Summary

Neutrophil Gelatinase-Associated Lipocalin (NGAL) is a class of small-molecule secreted glycoproteins, which can rapidly and sensitively reflect the degree of renal injury and the recovery process, and is a biological marker for detecting renal injury, sounding the alarm at the early stage of the disease, which has a high application value.NGAL is a useful indicator for the early diagnosis, treatment, and prognostic assessment of AKI.

The ReLIA NGAL Immunoassay is CE-marked cleared. For more details on ReLIA NGAL Immunoassay products and prices please contact us at  marketing@ReLIAchina.com

References

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