Metformin targets mitochondrial complex I to lower blood glucose levels.

Metformin is among the most prescribed antidiabetic drugs, but the primary molecular mechanism by which metformin lowers blood glucose levels is unknown. Previous studies have proposed numerous mechanisms by which acute metformin lowers blood glucose, including the inhibition of mitochondrial complex I of the electron transport chain (ETC). Here, we used transgenic mice that globally express the internal alternative NADH dehydrogenase (NDI1) protein to determine whether the glucose-lowering effect of acute oral administration of metformin requires inhibition of mitochondrial complex I of the ETC in vivo.

Inducible CCR2+ nonclassical monocytes mediate the regression of cancer metastasis.

A major limitation of immunotherapy is the development of resistance resulting from cancer-mediated inhibition of host lymphocytes. Cancer cells release CCL2 to recruit classical monocytes expressing its receptor CCR2 for the promotion of metastasis and resistance to immunosurveillance. In the circulation, some CCR2-expressing classical monocytes lose CCR2 and differentiate into intravascular nonclassical monocytes that have anticancer properties but are unable to access extravascular tumor sites.

Profibrotic monocyte-derived alveolar macrophages are expanded in patients with persistent respiratory symptoms and radiographic abnormalities after COVID-19.

Monocyte-derived alveolar macrophages drive lung injury and fibrosis in murine models and are associated with pulmonary fibrosis in humans. Monocyte-derived alveolar macrophages have been suggested to develop a phenotype that promotes lung repair as injury resolves. We compared single-cell and cytokine profiling of the alveolar space in a cohort of 35 patients with post-acute sequelae of COVID-19 who had persistent respiratory symptoms and abnormalities on a computed tomography scan of the chest that subsequently improved or progressed.