TRPC6 is altered in COVID-19 pneumonia.

In this Letter to the Editor supportive data were presented to a recent paper published in this journal reporting the involvement of TRP channels in COVID-19 pneumonia and its role for new therapies. Since gene expression of TRP channels was found in human lung tissues the protein was not being reported so far. TRP channels are supposed to be involved in the pulmonary inflammation and its symptoms such as fever, cough and others. Here, TRPC6 was investigated in tissues of normal human lungs and of SARS-Cov-2 infected lungs in a preliminary study. Tissue was obtained post mortem from anatomical body donations during dissections and during pathological dissections (13 normal, 4 COVID-19 pneumoniae) and processed for immunohistochemistry. In normal lungs TRPC6 was found in the ciliated epithelium, in the wall of larger lung vessels and in the alveolar septa. In COVID-19 pneumonia the distribution of TRPC6 was different. Inflammatory lesions, cellular infiltrates, hyaline membranes and fibrosis were labelled intensively as well as dilated capillaries. These observations are from four patients with COVID-19 pneumonia.The observations do not elucidate the molecular mechanisms but support the view that TRPC6 channels are involved in normal physiology of normal human lungs and in COVID-19 pneumonia. TRPC6 might aggravate SARS-2 induced inflammation and could be a target for inhibiting drugs.