Biomarker Identifies Sarcopenia Patients with Excessive Neurotrypsin Activity

A novel biomarker was developed to identify the subgroup of patients (40%), whose sarcopenia is caused by excessive neurotrypsin activity.

The biomarker developed by Neurotune (Zurich, Switzerland), is the 22 kDa C-terminal agrin fragment (CAF). When agrin is inactivated by neurotrypsin, CAF is released and can be detected in the blood. Elevated levels of CAF are indicative of increased neurotrypsin activity and a measure of reduced neuromuscular junctions (NMJs) strength. The NTCAF enzyme-linked immunosorbent assay (ELISA) detects CAF in human serum.

Neurotrypsin regulates the strength of communication between nerve and muscle cells by cleaving and inactivating agrin. Excessive neurotrypsin activity causes deterioration of the synapses and subsequently muscle atrophy.

CAF is detectable in serum in healthy adults, aged between 20-75 years, defining a normal range. Approximately 40% of sarcopenia patients show statistically significant increased CAF levels above normal.

NTCAF ELISA was developed by Neurotune in collaboration with MicroCoat Biotechnologie GmbH (Bernried am Starnberger See, Germany), and the Eureka-Eurostars program (Brussels, Belgium). It is available immediately from Neurotune.

Neurotune is continuing to develop the ELISA assay as a marker of dysfunction of the neurotrypsin/agrin system in other pathological conditions.

Sarcopenia is a debilitating muscle disorder frequently affecting the elderly for which there is currently no cure. It is defined as loss of skeletal muscle mass and strength that occurs with advancing age. The current diagnosis of the disease is by dual-emission X-ray absorptiometry (DXA) scan, which measures lean body mass (LBM) in combination with functional tests. This cumbersome technique does not provide information on the underlying cause of loss of LBM.

It is estimated that sarcopenia currently affects over 50 million people worldwide and with the aging population this is expected to increase to over 200 million in the next 40 years.

Neurotune develops medications to treat disorders of the human nervous system. MicroCoat Biotechnologie is active in the field of immune and nucleic acid diagnostics. The purpose of the Eurostars Program is to provide funding for market-oriented research and development by small and medium-sized enterprises.

Related Links:
Neurotune
MicroCoat Biotechnologie GmbH
Eureka-Eurostars program