Previtamin D3
Previtamin D3 - Related Videos
06:46
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03:47
Generation of Immature, Mature, and Tolerogenic Dendritic Cells from Monocytes
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This video demonstrates the generation of immature, mature, and tolerogenic dendritic cells, or DCs, from human monocytes. The incubation of monocytes with growth factors and cytokines leads to the production of immature DCs. In response to immune regulatory molecules, immature DCs differentiate into tolerogenic and mature DCs.
06:09
Generation of Immature, Mature and Tolerogenic Dendritic Cells with Differing Metabolic Phenotypes
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Cited by 37 •
2016
Immature dendritic cells can be selectively differentiated into tolerogenic or mature dendritic cells to regulate the balance between immunity and tolerance. This work presents a means to generate from immature monocyte derived dendritic cells (moDCs), in vitro tolerogenic and mature moDCs that differ in metabolic phenotypes.
FAQs
Ultraviolet B radiation acts on 7-dehydrocholesterol located in epidermal cell membranes and triggers a photochemical ring-opening reaction. This structural change produces previtamin D3 rather than cholecalciferol directly. The distinction is important because it separates the light-dependent chemical step from the later heat-driven rearrangement that completes vitamin D3 production.
Body heat drives the thermal isomerization of previtamin D3 into cholecalciferol, also called vitamin D3. This step differs from the initial ultraviolet reaction because it does not depend on another photochemical conversion. Together, the two stages link environmental radiation with normal physiological temperature and establish the molecular sequence leading toward biologically active vitamin D metabolites.
Previtamin D3 provides a biochemical link between events in epidermal membranes and later endocrine control of mineral balance. After its conversion to cholecalciferol, vitamin D3 is modified first in the liver and then in the kidneys. These sequential transformations generate active vitamin D metabolites that regulate calcium and phosphate absorption.
The pathway can be followed as a sequence of linked events: ultraviolet B exposure acts on 7-dehydrocholesterol in epidermal membranes, the ring-opening reaction forms previtamin D3, and body heat promotes conversion to cholecalciferol. Study then continues through liver and kidney modification, allowing the initial skin reaction to be connected with mineral regulation.
This intermediate allows researchers to examine how epidermal cell membranes participate in a physiologically important chemical pathway. Its formation depends on ultraviolet B radiation acting on a membrane-associated precursor, so the process connects skin structure and function with photochemistry. That connection helps explain how a local reaction in skin contributes to whole-body vitamin D biology.
The pathway ultimately supports regulation of calcium and phosphate absorption through active vitamin D metabolites formed after liver and kidney processing. These mineral-regulating effects are relevant to skeletal health because calcium balance is essential for the skeleton. Studying the intermediate therefore places sunlight-dependent chemistry within a broader framework of nutrient handling and physiological regulation.