# Serum Carnosinase 1 Is Not Associated with Insulin Resistance or Glucose Metabolism in a Type 1 Diabetes Cohort

## TL;DR

This study found no link between serum carnosinase 1 levels and glucose metabolism or insulin resistance in type 1 diabetes patients.

## Contribution

The study provides novel human evidence that serum CN1 does not affect glucose variability in type 1 diabetes.

## Key findings

- Insulin sensitivity and glucose variability parameters did not differ across CN1 tertiles.
- No association was found between serum CN1 and glucose metabolism indices in type 1 diabetes patients.

## Abstract

Background/Objectives: Preclinical studies suggest that the deleterious effect of a high serum carnosinase 1 (CN1) concentration is attributed to its adverse effects on insulin sensitivity and glucose metabolism. However, there is little evidence for a modulating role of CN1 in glucose metabolism in humans. Methods: We measured serum CN1 concentration in an observational type 1 diabetes cohort of 172 patients in whom glucose variability (MAGE, MODD, SD of individual blood glucose, mean, and CV) was recorded by blinded continuous glucose monitoring for 5–7 days. Furthermore, insulin dose per kg body weight was compared. Results: Insulin sensitivity (insulin dosage) and glucose variability parameters did not differ between different CN1 tertiles (p > 0.05). Conclusions: There was no association of serum CN1 with indices of glucose variability in this type 1 diabetes cohort.