Metformin is a drug widely prescribed to lower blood sugar. It is often used as an early treatment, with diet and lifestyle changes, for type 2 diabetes.
Metformin works by decreasing glucose production in the liver and reducing blood sugar levels, which in turn improves the body’s response to insulin. But scientists also note that metformin has anti-inflammatory properties, although the basis for this activity is not known.
In a study published online in the journal Cell Metabolism, a multi-institutional team led by researchers at the University of California San Diego School of Medicine identified the molecular mechanism of metformin’s anti-inflammatory activity.
In mouse studies, they found that metformin prevents pneumonia in animals infected with SARS-CoV-2, the virus that causes COVID-19.
Over the past year, several clinical studies have reported that the use of metformin by patients with diabetes and obesity before hospitalization due to “Covid-19” was associated with reduced symptom severity and mortality.
While these clinical studies suggest that metformin’s anti-inflammatory activity, rather than lowering blood glucose, could be responsible for reducing COVID-19 severity and mortality, none of the studies provided an explanation or prompted the conduct of large randomized clinical trials. necessary to get definitive answers.
Dr. Michael Karen, Distinguished Professor of Pharmacology, Pathology, and Metabolic Diseases, in the Ben and Wanda Hildyard Chair for Mitochondrial and Metabolic Diseases at UCSD School of Medicine, and co-senior author Elsa Sanchez Lopez, associate professor in the Department of Orthopedics, and Fellow Postdoc Hongsu Xian et al. focused on acute respiratory distress syndrome (ARDS), in a mouse model, a life-threatening condition in which fluid leaks into the lungs, making breathing difficult and limiting oxygen delivery to essential organs.
Acute respiratory distress syndrome is caused by trauma and bacterial or viral infections. It is a frequent cause of death among hospitalized patients due to “Covid-19”.
The researchers found that metformin given to mice before or after exposure to bacterial endotoxins, an alternative to bacterial pneumonia, inhibited the onset of acute respiratory distress syndrome and reduced its symptoms.
Metformin also significantly reduced mortality in endotoxin-deficient mice, inhibiting IL-1β production and the aggregation of inflammatory particles within alveolar macrophages, the immune cells found in the lungs.
IL-1β, along with IL-6, are small proteins called cytokines that trigger inflammation as an early immune response.
Their amounts are often very high in people infected with SARS-CoV-2, which leads to “cellular storms” in which the body begins to attack its own cells and tissues. They are signs that the acute immune response has gone awry.
Working with colleagues at the Scripps Research Institute, the UCSD researchers confirmed that metformin inhibits the activation of inflammation and prevents SARS-CoV-2-induced pneumonia in mice.
Source: Medical Express