Dear Colleagues,

 As a steroid hormone, vitamin D is widely known for its regulatory role in calcium homeostasis and bone formation, but it also has many other tissue-specific roles in cellular processes such as energy metabolism, growth, differentiation, apoptosis and angiogenesis, along with many others. Its hormonal effect manifests itself within seconds to minutes via signaling pathways through membrane-bound receptors (e.g. 1,25D3-MARRS, VDR or PDIA3). In addition, vitamin D can act as a transcription factor. The physiological consequences of these effects take several hours to develop. Interestingly and not surprisingly, the two modes of action largely overlap.

Vitamin D has recently gained new attention and importance with the recognition that in optimal levels, it is capable of reducing the severity of COVID-19. Based on these experiences, the importance and necessity of achieving optimal serum levels of Vitamin D has increased its role in many other diseases, such as respiratory infections, coronary artery disease, insulin resistance and type 2 diabetes, cancer, atherosclerosis, multiple sclerosis and aging. However, the detailed molecular mechanism of vitamin D deficiency leading to the development of such diseases is not yet fully understood, and neither is the relationship of the two regulatory modes, nor their importance and proportion in the development of vitamin D-related diseases.

In this Special Issue, we aim to accept original articles on the topic of vitamin D-related diseases, physiological conditions, and in vitro experiments that cover the molecular aspects of the interpretation, evaluation, intervention or treatment of the effects of vitamin D. We also accept reviews that explain the relationships, similarities, underlying factors, and preventive and therapeutic treatments of various diseases in connection with changes in vitamin D levels.

Dr. Németh Zsuzsanna

Guest Editor