Silver birch, Betula pendula Roth, is one of the most common trees in Europe. Due to its content of many biologically active substances, it has long been used in medicine and cosmetics, unlike the rare black birch, Betula obscura Kotula. The aim of the study was therefore to compare the antioxidant properties of extracts from the inner and outer bark layers of both birch trees towards the L929 line treated with acetaldehyde. Based on the lactate dehydrogenase test and the MTT test, 10 and 25% concentrations of extracts were selected for the antioxidant evaluation. All extracts at tested concentrations reduced the production of hydrogen peroxide, superoxide anion radical, and 25% extract decreased malonic aldehyde formation in acetaldehyde-treated cells. The chemical composition of bark extracts was accessed by IR and HPLC-PDA methods and surprisingly, revealed a high content of betulin and lupeol in the inner bark extract of B. obscura. Furthermore, IR analysis revealed differences in the chemical composition of the outer bark between black and silver birch extracts, indicating that black birch may be a valuable source of numerous biologically active substances. Further experiments are required to evaluate their potential against neuroinflammation, cancer, viral infections, as well as their usefulness in cosmetology.

In the colonic epithelium, fetal programming is induced by Yes-associated protein (YAP) signaling, which is associated with tumorigenesis and progression in colorectal cancer (CRC). While CRC was long considered a WNT driven disease, here we show that fetal programmed cells with activated YAP signaling can arise independently of WNT activation. Fetal programmed cells, in the presence of hyper- or hypo-activated WNT, have different characteristics and are associated with poor relapse. Furthermore, using various mouse models, we demonstrated the conserved characteristics of two different fetal programmed cell states with different WNT activation, which can be switched from a hyperactivated to hypoactivated WNT state based on genetic alteration, particularly Kras mutation. Taken together, these data redefine the key determinants of epithelial cell states in colorectal cancer and integrate emerging preclinical biology into a robust landscape of states observed in human and mouse.