Metabolic Solutions, Inc.
460 Amherst Street
Martin A. Baker
MSI helps pharmaceutical researchers to apply stable isotopes in drug efficacy and safety studies. Our services include study protocol consultation, building custom test kits and a responsive analytical service compliant with current FDA Good Laboratory Practices. Our products include numerous biomarkers for understanding liver function including the methionine breath test for mitochondrial function, the erythromycin breath test for CYP 3A4 activity and phenylalanine breath test that assesses cytosolic activity.
- Methionine Breath Test
This liver function test is based on the metabolism of 1-13C methionine (non-radioactive tracer) as a direct measure of hepatic mitochondrial function.
Metabolic Solutions offers a non-invasive liver function test that measures the degree and progression of mitochondrial liver impairment in patients with varied causes of liver disease. This liver function test is based on the metabolism of 1-13C methionine (non-radioactive tracer) as a direct measure of hepatic mitochondrial function and is called the methionine breath test. Applications for the methionine breath test include liver function monitoring for drug induced liver toxicity, evaluating liver damage in Non-Alcoholic Steatohepatitis (NASH) patients, and examination of liver transplantation prioritization.
- Erythromycin Breath Test
The Erythromycin Breath Test is a quantitative in vivo measure of hepatic CYP3A4 activity (cytochrome P450), the most important drug-metabolizing enzyme present in the liver.
The ERMBT™ uses a 3 µCi [C-14 N-methyl] erythromycin dose as a substrate for CYP3A4 enzyme. The substrate is injected intravenously into a hand or arm vein for rapid distribution in the body. Predominately liver CYP3A4 metabolizes the erythromycin via N-demethylation of the labeled methyl group to produce formaldehyde. The formaldehyde is converted rapidly to carbon dioxide by ubiquitous enzymes in the body. The labeled carbon dioxide appears in the breath. A single breath collection at 20 minutes after injection of the test dose of erythromycin estimates the percentage of administered radiolabel exhaled. The percent of carbon-14 appearance in the breath at 20 minutes correlates with the percent erythromycin metabolized per hour. A correlation equation derives a relative percent erythromycin metabolized which can be used to compare interpatient or intrapatient differences after various experimental treatments.