Effects of all-trans retinioic acid and tazarotene on MMP-1 and TIMP-1 expression in cultured human fibroblasts after heat shock / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the molecular mechanism of dermal damage in heat shock-induced skin aging by observing the expressions of metalloproteinase-1 (MMP-1) and tissue inhibitor of MMP-1 (TIMP-1) in retinoic acid-treated cultured human fibroblasts with heat shock.</p><p><b>METHODS</b>Cultured human fibroblasts were treated with tazarotene or all-trans-retinioic acid (at-RA) after heat shock for 30 min in 43 degrees celsius; water bath. Twenty-four hours later, MMP-1 and TIMP-1 contents in the supernatant of the cell culture medium were measured using enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>Both tazarotene and at-RA dose-dependently reduced the expression of MMP-1 and increased the expression of TIMP-1 in cultured human fibroblasts exposed to heat shock, and tazarotene produced stronger effect than at-RA.</p><p><b>CONCLUSION</b>Retinoic acid can reduce the expression of MMP-1 and increase the expression of TIMP-1 in cultured human fibroblasts, suggesting its therapeutic potential for heat shock-induced skin aging.</p>

Expressions of fibrillin-1, elastin and matrix metalloproteinase-1 and -9 in chronic actinic dermatitis in elderly patients / 南方医科大学学报

<p><b>UNLABELLED</b>To investigate the expressions of fibrillin-1, elastin and matrix metalloproteinase-1 and -9 (MMP-1, 9) in chronic actinic dermatitis in elderly patients and explore the pathogenesis of the disease.</p><p><b>METHODS</b>Twenty-three patients with chronic actinic dermatitis were examined for the expressions of fibrillin-1, elastin, MMP-1, and MMP-9 with immunohistochemistry in the skin lesions. Image analysis was carried out to measure MMP-1 and MMP-9 expressions semi-quantitatively.</p><p><b>RESULTS</b>In the skin lesions of patients with chronic actinic dermatitis, elastin expression was obviously reduced or absent in the papillary dermis. The elastic fibers were disorderly arranged in the reticular dermis with local aggregation in some regions. Obvious fibrillin-1 deposition was found in the reticular dermis. Increased expressions of MMP-1, but not that of MMP-9, was found in the skin lesions of the patients.</p><p><b>CONCLUSION</b>Elastin and fibrillin-1 deposition can be found in the skin lesions in patients with chronic actinic dermatitis, suggesting the association of increased MMP-1 expression with the elastic tissue degeneration in the lesions. MMP-9 does not exhibit an obvious association with the pathogenesis of chronic actinic dermatitis in elderly patients.</p>

Inhibition of promyelocytic leukemia gene by tazarotene in hyperproliferative epidermis of psoriasis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the mechanism of tazarotene against active psoriasis vulgaris.</p><p><b>METHODS</b>A randomized, controlled trial was conducted in 43 patients with active psoriasis vulgaris, who were divided into tazarotene and control groups. Promyelocytic leukemia (PML) mRNA in active psoriatic lesions before and 14 days after tazarotene treatment was detected by in situ hybridization.</p><p><b>RESULTS</b>PML mRNA expression was detected not only in the basal layer (86.96%), but also in the suprabasal layers of the epidermis in the manner of focal expression (78.26%). After tazarotene treatment, virtually no PML mRNA expression could be detected in the psoriatic lesions (8.69% in the basal layer and 4.35% in the suprabasal layers). PML mRNA expression in the control group underwent no obvious changes during the observation.</p><p><b>CONCLUSIONS</b>Tazarotene may inhibit abnormal proliferation of keratinocytes through down-regulating PML gene expression in active psoriatic epidermis.</p>

Expression of costimulatory molecules on peripheral blood lymphocytes of patients with idiopathic thrombocytopenic purpura / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the expressions of costimulators on peripheral T and B lymphocytes in patients with idiopathic thrombocytopenic purpura (ITP).</p><p><b>METHODS</b>The expression of B7-CD(28) and CD(40) of peripheral lymphocytes was measured by flow cytometry in 21 ITP patients and 9 normal subjects. The expression of PAIgG was measured by ELISA method.</p><p><b>RESULTS</b>The expression of CD(4)(+)CD(28)(+) was lower in ITP patients than in normal controls, but the expression of CD(86)(+) and CD(86)(+)CD(19)(+) was higher in ITP patients than in normal controls, while the expression of CD(80)(+), CD(40)(+), CD(28)(+), CD(19)(+)CD(86)(+), CD(19)(+)CD(40)(+), CD(4)(+)CD(28)(+)/CD(4)(+), CD(19)(+)CD(80)(+)/CD(19)(+) and CD(19)(+)CD(40)(+)/CD(19)(+) in ITP patients was normal. The PAIgG level was higher in 16 patients with a mean of (184.62 +/- 38.00) ng/10(7) plt. A positive correlation was found between PAIgG and CD(19)(+)CD(86)(+)/CD(19)(+) expression.</p><p><b>CONCLUSION</b>There is no deficiency in expression of CD(28) on CD(4)(+) T lymphocytes in ITP patients. The change of CD(86) expression on B lymphocytes is possibly involved in pathophysiology of ITP, which may provide a theoretical instruction for ITP patients immunological therapy.</p>