| 1. |
- Chamcheu, Jean Christopher, et al.
(författare)
-
Chemical Chaperones Protect Epidermolysis Bullosa Simplex Keratinocytes from Heat Stress-Induced Keratin Aggregation : Involvement of Heat Shock Proteins and MAP Kinases
- 2011
-
Ingår i: Journal of Investigative Dermatology. - : Elsevier BV. - 0022-202X .- 1523-1747. ; 131:8, s. 1684-1691
-
Tidskriftsartikel (refereegranskat)abstract
- Epidermolysis bullosa simplex (EBS) is a blistering skin disease caused by mutations in keratin genes (KRT5 or KRT14), with no existing therapies. Aggregates of misfolded mutant keratins are seen in cultured keratinocytes from severe EBS patients. In other protein-folding disorders, involvement of molecular chaperones and the ubiquitin-proteasome system may modify disease severity. In this study, the effects of heat stress on keratin aggregation in immortalized cells from two patients with EBS (KRT5) and a healthy control were examined with and without addition of various test compounds. Heat-induced (43 °C, 30 minutes) aggregates were observed in all cell lines, the amount of which correlated with the donor phenotype. In EBS cells pre-exposed to proteasome inhibitor, MG132, and p38-mitogen-activated protein kinase (MAPK) inhibitor, SB203580, the proportion of aggregate-positive cells increased, suggesting a role of proteasomes and phosphorylation in removing mutated keratin. In contrast, aggregates were reduced by pretreatment with two chemical chaperones, trimethylamine N-oxide (TMAO) and 4-phenylbutyrate (4-PBA). TMAO also modulated stress-induced p38/c-jun N-terminal kinase (JNK) activation and expression of heat shock protein (HSPA1A), the latter of which colocalized with phosphorylated keratin 5 in EBS cells. Taken together, our findings suggest therapeutic targets for EBS and other keratinopathies.
|
|
| 2. |
- Chamcheu, Jean Christopher, et al.
(författare)
-
Chemical chaperones protect epidermolysis bullosa simplex keratinocytes from heat stress-induced keratin aggregation: : Involvement of heat shock proteins and MAP kinases
-
Ingår i: Journal of Investigative Dermatology. - 0022-202X .- 1523-1747.
-
Tidskriftsartikel (refereegranskat)abstract
- Epidermolysis bullosa simplex (EBS) is an inherited epithelial tissue fragility disorder due to mutations in keratin genes (KRT5 or KRT14), with no existing therapies. Aggregates of misfolded mutant keratins are seen in cultured keratinocytes from severe EBS patients. In some protein folding disorders such as cystic fibrosis and Alzheimer’s disease, chaperones and the ubiquitin-proteasome system modify disease severity, suggesting a novel therapeutic approach even for EBS. In this study, the effects of two chemical chaperones (trimethylamine-N oxide (TMAO) and 4-phenylbutyrate (4-PBA)) on heat stress-induced keratin aggregation responses were examined in newly and previously established immortalized control and EBS patient-derived keratinocyte cell lines. Heat-induced keratin-positive aggregates were observed in all EBS cells, which were most prominent in severe keratin-defective cell lines and less so in normal cells. The proportion of cells containing aggregates were dramatically reduced by TMAO and 4-PBA pretreatment. Furthermore, heat stress greatly induced MAP kinase activation (p38 and JNK) and increased Hsp70/Hsc70 expression, and TMAO was able to transiently modulate these effects. The results suggest that TMAO rescue may involve components of the endogenous chaperone and MAPK machineries, which may represent novel targets for the development of more effective treatments for EBS and other keratin-related genetic disorders.
|
|
| 3. |
- Chamcheu, Jean Christopher, et al.
(författare)
-
Immortalized keratinocytes derived from patients with epidermolytic ichthyosis reproduce the disease phenotype : A useful in vitro model for testing new treatments
- 2011
-
Ingår i: British Journal of Dermatology. - : British Association of Dermatologists. - 0007-0963 .- 1365-2133. ; 164:2, s. 263-272
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Epidermolytic ichthyosis (EI) is a skin fragility disorder caused by mutations in genes encoding suprabasal keratins 1 and 10. While the aetiology of EI is known, model systems are needed for pathophysiological studies and development of novel therapies. Objectives To generate immortalized keratinocyte lines from patients with EI for studies of EI cell pathology and the effects of chemical chaperones as putative therapies. Methods We derived keratinocytes from three patients with EI and one healthy control and established immortalized keratinocytes using human papillomavirus 16-E6/E7. Growth and differentiation characteristics, ability to regenerate organotypic epidermis, keratin expression, formation of cytoskeletal aggregates, and responses to heat shock and chemical chaperones were assessed. Results The cell lines EH11 (K1-p.Val176-Lys197del), EH21 (K10-p.156Arg>Gly), EH31 (K10-p.Leu161-Asp162del) and NKc21 (wild-type) currently exceed 160 population doublings and differentiate when exposed to calcium. At resting state, keratin aggregates were detected in 9% of calcium-differentiated EH31 cells, but not in any other cell line. Heat stress further increased this proportion to 30% and also induced aggregates in 3% of EH11 cultures. Treatment with trimethylamine N-oxide and 4-phenylbutyrate (4-PBA) reduced the fraction of aggregate-containing cells and affected the mRNA expression of keratins 1 and 10 while 4-PBA also modified heat shock protein 70 (HSP70) expression. Furthermore, in situ proximity ligation assay suggested a colocalization between HSP70 and keratins 1 and 10. Reconstituted epidermis from EI cells cornified but EH21 and EH31 cells produced suprabasal cytolysis, closely resembling the in vivo phenotype. Conclusions These immortalized cell lines represent a useful model for studying EI biology and novel therapies.
|
|
| 4. |
- Hagforsen, Eva, et al.
(författare)
-
Calcium homeostasis and body composition in patients with palmoplantar pustulosis : a case-control study
- 2012
-
Ingår i: British Journal of Dermatology. - : Oxford University Press (OUP). - 0007-0963 .- 1365-2133. ; 166:1, s. 74-81
-
Tidskriftsartikel (refereegranskat)abstract
- Background Palmoplantar pustulosis (PPP) is a common disease strongly associated with smoking, autoimmune comorbidities and a deranged calcium homeostasis. It is unclear whether these changes in calcium homeostasis are a consequence of vitamin D status, abnormal dermal vitamin D synthesis or whether they are substantiated in effects on bone mineral density (BMD). Objectives To study the vitamin D status and BMD in patients with PPP. Methods In comparisons with two sets of controls (n = 101 for serum analyses and n = 5123 for BMD analyses), we therefore aimed to investigate whether PPP (59 cases) was associated with serum levels of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, whether patients with PPP had decreased BMD and finally if the dermal expression of 25-hydroxyvitamin D(3) -1α-hydroxylase (CYP27B1) and the vitamin D receptor (VDR) were affected in PPP skin lesions. Results We found no differences in mean serum 25-hydroxyvitamin D levels between cases and controls, whereas PPP cases displayed 17·8 pmol L(-1) lower (P = 0·04) values in 1,25-dihydroxyvitamin D. BMD at the hip, lumbar spine or of total body did not differ substantially between cases and controls. Finally, patients with PPP had lower dermal expression of CYP27B1 and VDR in affected skin lesions. Conclusions The increase in serum calcium levels and suppressed parathyroid hormone in patients with PPP were not attributable to derangements in vitamin D status and these patients did not have lower BMD.
|
|
| 5. |
- Lindqvist, Ulla, et al.
(författare)
-
Dermal Distribution of Hyaluronan in Psoriatic Arthritis : Coexistence of CD44, MMP3 and MMP9
- 2012
-
Ingår i: Acta Dermato-Venereologica. - Uppsala : Medical Journals Sweden AB. - 0001-5555 .- 1651-2057. ; 92:4, s. 372-377
-
Tidskriftsartikel (refereegranskat)abstract
- Psoriatic arthritis is a chronic systemic disease in which patients develop persistent inflammation of the skin and joints, leading to disability and joint damage. The extracellular component hyaluronan (HA) plays an important role in regulatory processes such as inflammation, wound healing and tumour progression. At any site of inflammation HA can be depolymerized to low-molecular weight fragments, which, in turn, induce an array of inflammatory mediators that can lead to chronic inflammation. This study describes the serum concentration and dermal distribution of HA, its receptor CD44 and the metalloproteinases 3 and 9 in skin biopsies from patients with different types of psoriatic arthritis. Fifty-one patients with psoriatic arthritis were included in the study and classified as oligo- or poly-arthritic PsA with and without treatment. Biopsies were obtained from both involved and non-involved skin and compared with biopsies from healthy individuals. Serum HA was analysed for estimation of the total turnover of HA. The main findings were an overall redistribution of HA in both involved and non-involved psoriatic skin and an epidermal imbalance between HA and CD44. The structurally and functionally important basement membrane zone was found to be disintegrated and devoid of HA irrespective of the type of articular involvement, treatment or skin affection.
|
|
| 6. |
|
|
| 7. |
- Lindqvist, Ulla, et al.
(författare)
-
Patients with psoriatic arthritis have an increased number of lymphocytes in the duodenal mucosa in comparison with patients with psoriasis vulgaris
- 2006
-
Ingår i: Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 33:5, s. 924-927
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To determine if there is evidence of inflammation in the duodenal mucosa in patients with psoriatic arthritis (PsA) and to compare the results with those in patients with psoriasis vulgaris (PsV). METHODS: Nineteen consecutive patients with PsA underwent gastroduodenoscopy, and biopsy specimens were taken from the duodenal and gastric mucosa. In addition to routine processing, the duodenal mucosal specimens were stained for CD3+, CD8+ and CD4+ T lymphocytes, tryptase-positive mast cells, and EG2-positive eosinophil granulocytes. The results were compared with those in duodenal mucosal specimens from patients with PsV and patients with irritable bowel syndrome. RESULTS: Compared with PsV patients (without antibodies against gliadin), patients with PsA had a highly significant increase in intraepithelial CD3+ and CD8+ lymphocytes and also in CD4+ lymphocytes in the lamina propria in the villi. The lymphocyte increase was not related to presence of IgA antibodies against gliadin, endomysium, or transglutaminase, or to concomitant gastritis. Patients with PsA and PsV showed a pronounced increase in mast cells and eosinophil granulocytes. CONCLUSION: The increased lymphocyte infiltration in the duodenal mucosa in PsA, but not in PsV, might indicate different pathogenetic mechanisms in these psoriasis variants.
|
|
| 8. |
- Michaëlsson, Gerd, et al.
(författare)
-
Gluten-free diet in psoriasis patients with antibodies to gliadin results in decreased expression of tissue transglutaminase and fewer Ki67+ cells in the dermis
- 2003
-
Ingår i: Acta Dermato-Venereologica. - : Medical Journals Sweden AB. - 0001-5555 .- 1651-2057. ; 83:6, s. 425-429
-
Tidskriftsartikel (refereegranskat)abstract
- Previous studies have shown that 16% of patients with psoriasis vulgaris have IgA and/or IgG antibodies to gliadin, but few have antibodies to endomysium. The increase in duodenal intraepithelial lymphocytes was mild. Still, highly significant clinical improvement was observed after 3 months on a gluten-free diet. This study surveys certain immunohistological aspects of involved and non-involved skin in 28 AGA-positive psoriasis patients before and after 3 months of a gluten-free diet. Staining was performed for CD4+ T lymphocytes, Langerhans' cells, endothelium, proliferating (Ki67) cells and tissue transglutaminase. In the entire group of patients, as well as in those on a gluten-free diet as the only treatment, Ki67 + cells in involved dermis were highly significantly decreased after the diet. There was a significant decrease in Ki67 + cells even in patients without increased intraepithelial lymphocytes. Tissue transglutaminase was highly overexpressed in involved skin in the papillary endothelium, and decreased by 50% after gluten-free diet. The possible role of tissue transglutaminase in the pathogenesis of psoriasis needs further investigation.
|
|
| 9. |
- Michaëlsson, Gerd, et al.
(författare)
-
Palmoplantar pustulosis and gluten sensitivity : A study of serum antibodies against gliadin and tissue transglutaminase, the duodenal mucosa and effects of gluten-free diet
- 2007
-
Ingår i: British Journal of Dermatology. - : Oxford University Press (OUP). - 0007-0963 .- 1365-2133. ; 156:4, s. 659-666
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Palmoplantar pustulosis (PPP) is a chronic inflammatory disease affecting mainly smoking women. Some patients also have psoriasis. A subgroup of patients with psoriasis has been shown to have silent gluten sensitivity with relevance for their psoriasis. Nothing is known about gluten sensitivity in PPP. Objectives: To find out whether any patients with PPP are gluten-sensitive and whether this might be relevant for the PPP activity. Patients and methods: One hundred and twenty-three patients (113 women) with PPP participated. Screening for IgA antibodies against gliadin and tissue transglutaminase (tTG) was performed, the duodenal mucosa in patients with and without these antibodies was studied and the effect of a gluten-free diet (GFD) was followed up. Results: Twenty-two patients (18%) had IgA antibodies against gliadin and nine of 94 (10%) against tTG. Twelve patients with antibodies and 11 without underwent gastro-duodenoscopy. Four displayed villous atrophy, whereas all other specimens were judged as essentially normal at routine staining. However, with immunohistochemistry, the numbers of CD3+ and CD8+ lymphocytes in the epithelium were found to be increased in patients with any type of antibody, although they were most numerous in those with both types of antibodies. Seven of 123 patients (6%) had coeliac disease (three previously diagnosed). Patients with antibodies who adhered to the GFD displayed total or nearly total clearance of the skin lesions and normalization of the antibody levels. Conclusions: Patients with PPP should be screened for antibodies against gliadin and tTG. Those with antibodies can be much improved on a GFD regardless of the degree of mucosal abnormalities.
|
|
| 10. |
- Michaëlsson, Gerd, et al.
(författare)
-
Psoriasis patients with antibodies to gliadin can be improved by a gluten-free diet
- 2000
-
Ingår i: British Journal of Dermatology. - : Oxford University Press (OUP). - 0007-0963 .- 1365-2133. ; 142:1, s. 44-51
-
Tidskriftsartikel (refereegranskat)abstract
- In a previous screening study, 16% of patients with psoriasis had IgA and/or IgG antibodies to gliadin (AGA). The aim of the present study was to evaluate the effect of a gluten-free diet (GFD) in 33 AGA-positive and six AGA-negative psoriasis patients. Of the 33 AGA-positive patients, two had IgA antibodies to endomysium (EmA) and 15 an increased number of lymphocytes in the duodenal epithelium, but in some this increase was slight. Two patients had villous atrophy. A 3-month period on a GFD was followed by 3 months on the patient's ordinary diet. The severity of psoriasis was evaluated with the psoriasis area and severity index (PASI). The examining dermatologists were unaware of the EmA and duodenal biopsy results throughout the study. Thirty of the 33 patients with AGA completed the GFD period, after which they showed a highly significant decrease in mean PASI. This included a significant decrease in the 16 AGA-positive patients with normal routine histology in duodenal biopsy specimens. The AGA-negative patients were not improved. After GFD, the AGA values were lower in 82% of those who improved. There was a highly significant decrease in serum eosinophil cationic protein in patients with elevated AGA. When the ordinary diet was resumed, the psoriasis deteriorated in 18 of the 30 patients with AGA who had completed the GFD period. In conclusion, psoriasis patients with raised AGA might improve on a GFD even if they have no EmA or if the increase in duodenal intraepithelial lymphocytes is slight or seemingly absent.
|
|
