Topically Applied Vitamin C Enhances the mRNA Level of Collagens I and III, Their Processing Enzymes and Tissue Inhibitor of Matrix Metalloproteinase 1 in the Human Dermis11Part of this work was presented in poster form at the American Academy of Dermatology, San Francisco, CA, March 10–15, 2000.

Abstract

Ascorbic acid (vitamin C) is a cofactor required for the function of several hydroxylases and monooxygenases. It is not synthesized in humans and some other animal species and has to be provided by diet or pharmacologic means. Its absence is responsible for scurvy, a condition related in its initial phases to a defective synthesis of collagen by the reduced function of prolylhydroxylase and production of collagen polypeptides lacking hydroxyproline, therefore, they are unable to assemble into stable triple-helical collagen molecules. In fibroblast cultures, vitamin C also stimulates collagen production by increasing the steady-state level of mRNA of collagen types I and III through enhanced transcription and prolonged half-life of the transcripts. The aim of the experimental work has been to evaluate the effect on dermal cells of a preparation of vitamin C topically applied on one side vs placebo on the other side of the dorsal face of the upper forearm of postmenopausal women. Biopsies were collected on both sides and the level of mRNA measured by non competitive reverse transcription-polymerase chain reaction made quantitative by the simultaneous transcription and amplification of synthetic RNA used as internal standards. The mRNA of collagen type I and type III were increased to a similar extent by vitamin C and that of three post-translational enzymes, the carboxy- and amino-procollagen proteinases and lysyloxidase similarly increased. The mRNA of decorin was also stimulated, but elastin, and fibrillin 1 and 2 were not modified by the vitamin. The expression of matrix metalloproteinases 1, 2, and 9 was not significantly changed, but an increased level of tissue inhibitor of matrix metalloproteinase 1 mRNA was observed without modification of tissue inhibitor of matrix metalloproteinase 2 mRNA. The stimulating activity of topical vitamin C was most conspicuous in the women with the lowest dietary intake of the vitamin and unrelated to the level of actinic damage. The results indicate that the functional activity of the dermal cells is not maximal in postmenopausal women and can be increased.

Osteoblast differentiation influences androgen and estrogen receptor-alpha and -beta expression

“…This temporal sequence of differentiation can also be described by changes in gene expression as we have previously shown (Birnbaum & Wiren 1994), where collagen mRNA abundance was high during proliferation, then declined; osteopontin expression was elevated during both the proliferation and mineralization; alkaline phosphatase increased as proliferation slowed; and osteocalcin expression increased during the mineralization stage, then declined in postmineralization cultures. This temporal sequence of differentiation of osteoblastic cultures does not proceed normally unless differentiation medium containing ascorbic acid is added , which can regulate transcription and post-transcriptional and post-translational processing of collagen (Nusgens et al 2001).…”

Histological and transcriptional study of angiogenesis and lymphangiogenesis in uninvolved skin, acute pinpoint lesions and established psoriasis plaques: An approach of vascular development chronology in psoriasis

“…RT-PCR were performed to measure 28S rRNA, K16, VEGF-A, VEGF-C, VEGFR2, VEGFR3, NRP-1, NRP-2a, prox-1, PlGF-1 and -2 mRNA, using a Superscript II Reverse Transcriptase (Invitrogen, Merelbeke, Belgium) and Takara Taq polymerase (Biomedical group, Shiga, Japan). RT-PCR amplifications were performed in an automated thermal cycler (GeneAmp PCR System 9700, Applied Biosystems, Foster City, USA) with different pairs of primers as previously described [10,27,28]. For VEGF-A and PlGF, forward and reverse primers were chosen in regions surrounding the alternatively skipped sequences, allowing the discrimination of the various splice variants on the basis of the size of their amplification product [29].…”

Changes in Matrix Gene and Protein Expressions After Single or Repeated Exposure to One Minimal Erythemal Dose of Solar-simulated Radiation in Human Skin In Vivo

“…This quantitative assay allows a comparative analysis of samples, displaying an extended range in expression level. The accuracy, linearity of response and reliability of this procedure have been reported previously (14,15).…”

“…Total RNA was extracted and purified by ultracentrifugation on a cesium chloride cushion (13) from snap frozen biopsy samples collected from six volunteers as described previously (14). Specific mRNA and 28S ribosomal RNA (rRNA) were measured by quantitative noncompetitive RT-PCR.…”

“…Specific mRNA and 28S ribosomal RNA (rRNA) were measured by quantitative noncompetitive RT-PCR. Pairs of RT-PCR primers were selected as described previously (14)(15)(16). For each investigated mRNA, a synthetic RNA (sRNA) was generated, according to previously published procedures (15,17), to monitor in each reaction tube the efficiency of both reverse transcription and amplification reactions (PCR).…”