Physicians Lab, a provider of at-home lab testing for integrative medicine and wellness, launched a new at-home lab test that measures the analytes myostatin and follistatin. 

The test will show the current myostatin and follistatin levels and the ratio of myostatin to follistatin, and will be useful for monitoring muscle loss or growth in individuals, the company says. 

“Our research team has delivered another test that’s convenient, reliable and has a fast turnaround time,” says Jaime Rios, CEO of Physicians Lab. “Our method is minimally invasive. We can provide valuable insight into a person’s muscle development without burdening them by taking a large blood sample. Our team is excited to expand Physicians Lab solutions and to offer this at-home lab test to integrative providers and directly to health-conscious consumers.” 

Myostatin, a member of the transforming growth factor-beta (TGF-β) superfamily, is a potent regulator of muscle growth. It acts primarily to inhibit muscle development, maintaining muscle size by inhibiting both the growth and differentiation of muscle cells. Assessing myostatin levels can provide a valuable understanding of muscle homeostasis and the pathological mechanisms underlying muscle-wasting diseases.

Meanwhile, follistatin serves as an antagonist to myostatin and other members of the TGF-β family. By binding to and inhibiting these growth factors, follistatin promotes muscle growth and has a critical role in muscle repair and regeneration. It’s involved in a variety of biological processes beyond muscle growth, including reproduction and the regulation of inflammation.

“GLP-1 has become a popular weight loss intervention,” Rios says. “Understanding myostatin levels could be beneficial to patients on GLP-1 agonists like semaglutide, since up to 40 percent of the weight loss during therapy could come from lean mass loss, which includes muscle.”

Physicians Lab uses a technique called bloodspot microsampling. This method allows for the collection of blood samples in a minimally invasive manner, according to the company.  It requires only a small volume of blood that can be obtained from a simple finger prick.

To determine the values of myostatin and follistatin, Physicians Lab uses a high-sensitivity Enzyme-Linked Immunosorbent Assay (ELISA) technique. This ensures accurate quantification of myostatin and follistatin levels in these small-volume samples, says Physicians Lab.

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