Publications by authors named "R R Sicinski"
The biologically active metabolite of vitamin D - calcitriol - is a hormone involved in the regulation of calcium-phosphate homeostasis, immunological processes and cell differentiation, being therefore essential for the proper functioning of the human body. This suggests many applications of this steroid in the treatment of diseases such as rickets, psoriasis and some cancers. Unfortunately, using therapeutic doses of calcitriol is associated with high concentrations of this compound which causes hypercalcemia.
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- CYP11A1 and CYP27A1 enzymes convert tachysterol, a byproduct of previtamin D, into biologically active metabolites 20S-hydroxytachysterol (20S(OH)T) and 25-hydroxytachysterol (25(OH)T), which were found in human skin and blood.
- Both metabolites inhibit the growth of skin cells and promote gene expression related to cell differentiation and antioxidants, similar to the effects of the active form of vitamin D.
- Additionally, these metabolites interact with various receptors such as the vitamin D receptor (VDR) and the aryl hydrocarbon receptor (AhR), suggesting they play significant roles in cellular processes and providing new
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- Rotamers are stereoisomers formed by rotating around σ bonds, and they can quickly interchange, especially at room temperature.
- Xylitol, a widely used sweetener, can exist in different rotamer forms due to rotation at specific carbon bonds, resulting in distinguishable structures.
- Theoretical calculations revealed that the geometry differences in these rotamers, particularly those involving hydroxyl group rotations, are more significant than those involving the carbon chain but are challenging to observe with X-ray powder diffraction.
New and more efficient routes of chemical synthesis of vitamin D (D) hydroxy (OH) metabolites, including 20S(OH)D, 20S,23S(OH)D and 20S,25(OH)D, that are endogenously produced in the human body by CYP11A1, and of 20S,23R(OH)D were established. The biological evaluation showed that these compounds exhibited similar properties to each other regarding inhibition of cell proliferation and induction of cell differentiation but with subtle and quantitative differences. They showed both overlapping and differential effects on T-cell immune activity.
View Article and Find Full Text PDFA new series of highly biologically active (20S,22R)-1α,25-dihydroxy-22-methyl-2-methylene-vitamin D analogs, possessing different side chains, have been efficiently prepared as potential agents for medical therapy. Design of these synthetic targets was based on the analysis of the literature data and molecular docking experiments. The synthetic strategy involved Sonogashira coupling of the known A-ring dienyne with the C,D-ring enol triflates, obtained from the corresponding Grundmann ketones.
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