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1.
Nature ; 614(7947): 287-293, 2023 02.
Article in English | MEDLINE | ID: mdl-36725928

ABSTRACT

The ability of the ancient Egyptians to preserve the human body through embalming has not only fascinated people since antiquity, but also has always raised the question of how this outstanding chemical and ritual process was practically achieved. Here we integrate archaeological, philological and organic residue analyses, shedding new light on the practice and economy of embalming in ancient Egypt. We analysed the organic contents of 31 ceramic vessels recovered from a 26th Dynasty embalming workshop at Saqqara1,2. These vessels were labelled according to their content and/or use, enabling us to correlate organic substances with their Egyptian names and specific embalming practices. We identified specific mixtures of fragrant or antiseptic oils, tars and resins that were used to embalm the head and treat the wrappings using gas chromatography-mass spectrometry analyses. Our study of the Saqqara workshop extends interpretations from a micro-level analysis highlighting the socio-economic status of a tomb owner3-7 to macro-level interpretations of the society. The identification of non-local organic substances enables the reconstruction of trade networks that provided ancient Egyptian embalmers with the substances required for mummification. This extensive demand for foreign products promoted trade both within the Mediterranean8-10 (for example, Pistacia and conifer by-products) and with tropical forest regions (for example, dammar and elemi). Additionally, we show that at Saqqara, antiu and sefet-well known from ancient texts and usually translated as 'myrrh' or 'incense'11-13 and 'a sacred oil'13,14-refer to a coniferous oils-or-tars-based mixture and an unguent with plant additives, respectively.


Subject(s)
Embalming , Mummies , Humans , Egypt, Ancient , Embalming/economics , Embalming/history , Embalming/methods , Gas Chromatography-Mass Spectrometry , History, Ancient , Mummies/history , Resins, Plant/analysis , Resins, Plant/history , Ceramics/chemistry , Ceramics/history , Tars/analysis , Tars/history , Plant Oils/analysis , Plant Oils/history , Mediterranean Region , Tropical Climate , Forests , Tracheophyta/chemistry , Commerce/history
2.
Int J Mol Sci ; 25(12)2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38928138

ABSTRACT

Based on the lack of differences in progression-free and overall survival after a median follow-up of 93 months in our HOVON-65/GMMG-HD4 trial (German part; n = 395) randomizing VAD induction (vincristin/adriamycin/dexamthasone)/tandem-transplantation/thalidomide-maintenance vs. PAD induction (bortezomib/adriamycin/dexamethasone)/tandem transplantation/bortezomib maintenance, we discern how chromosomal aberrations determine long-term prognosis by different patterns of association with proliferation and treatment-dependent response, whether responses achieved by different regimens are equal regarding prognosis, and whether subpopulations of patients could be defined as treatable without upfront "novel agents" in cases of limited resources, e.g., in low- or middle-income countries. Serum parameters and risk factors were assessed in 395 patients. CD138-purified plasma cells were subjected to fluorescence in situ hybridization (n = 354) and gene expression profiling (n = 204). We found chromosomal aberrations to be associated in four patterns with survival, proliferation, and response: deletion (del) del17p13, del8p21, del13q14, (gain) 1q21+, and translocation t(4;14) (all adverse) associate with higher proliferation. Of these, del17p is associated with an adverse response (pattern 1), and 1q21+, t(4;14), and del13q14 with a treatment-dependent better response (pattern 2). Hyperdiploidy associates with lower proliferation without impacting response or survival (pattern 3). Translocation t(11;14) has no association with survival but a treatment-dependent adverse response (pattern 4). Significantly fewer patients reach a near-complete response or better with "conventional" (VAD) vs. bortezomib-based treatment after induction or high-dose melphalan. These patients, however, show significantly better median progression-free and overall survival. Molecularly, patients responding to the two regimens differ in gene expression, indicating distinct biological properties of the responding myeloma cells. Patients with normal renal function (89.4%), low cytogenetic risk (72.5%), or low proliferation rate (37.9%) neither benefit in progression-free nor overall survival from bortezomib-based upfront treatment. We conclude that response level, the treatment by which it is achieved, and molecular background determine long-term prognosis. Chromosomal aberrations are associated in four patterns with proliferation and treatment-dependent responses. Associations with faster and deeper responses can be deceptive in the case of prognostically adverse aberrations 1q21+ and t(4;14). Far from advocating a return to "outdated" treatments, if resources do not permit state-of-the-art-treatment, normal renal function and/or molecular profiling identifies patient subpopulations doing well without upfront "novel agents".


Subject(s)
Chromosome Aberrations , Multiple Myeloma , Humans , Multiple Myeloma/genetics , Multiple Myeloma/drug therapy , Multiple Myeloma/mortality , Multiple Myeloma/pathology , Female , Male , Middle Aged , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cell Proliferation/drug effects , Prognosis , Adult , Developing Countries , Dexamethasone/therapeutic use , Dexamethasone/pharmacology , Bortezomib/therapeutic use , Bortezomib/pharmacology , Thalidomide/therapeutic use
3.
Br J Cancer ; 128(12): 2295-2306, 2023 06.
Article in English | MEDLINE | ID: mdl-37045906

ABSTRACT

BACKGROUND: The prognostic significance of tumour budding (TB) and minimal cell nest size (MCNS) was shown in human papillomavirus (HPV)-negative head and neck squamous cell carcinomas (HNSCC). However, the optimisation of cutpoints, the prognostic impact in HPV-positive HNSCC, and the comparison with other histopathological grading systems are insufficiently investigated. METHODS: TB and MCNS were analysed digitally in 1 and 10 high-power fields (HPF) of 331 HPV-positive and HPV-negative cases from TCGA. Optimising the cutpoints a new cellular dissociation grading (CDG) system was defined and compared to the WHO grading and the Brandwein-Gensler (BG) risk model. RESULTS: The two-tiered CDG system based solely on TB yielded optimal prognostic stratification with shortened overall survival for CDG-high cases. Optimal cut-offs were two buds (1 HPF) and six buds (10 HPF), respectively. Analysing MCNS did not add prognostic significance to quantifying TB. CDG was a significant prognostic marker in HPV-negative and HPV-positive tumours and prognostically superior to the WHO and BG systems. High CDG was associated with clinically occult lymph-node metastases. CONCLUSIONS: The most comprehensive study of TB in HNSCC so far confirmed its prognostic impact in HPV-negative tumours and for the first time in HPV-positive tumours. Further studies are warranted to evaluate its applicability for therapy guidance in HNSCC.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Papillomavirus Infections , Humans , Squamous Cell Carcinoma of Head and Neck , Carcinoma, Squamous Cell/pathology , Prognosis , Papillomavirus Infections/complications , Papillomaviridae , Biomarkers
4.
Br J Cancer ; 127(8): 1540-1549, 2022 11.
Article in English | MEDLINE | ID: mdl-35871236

ABSTRACT

BACKGROUND: Cholangiocarcinoma (CCA) is a primary malignancy of the biliary tract with a dismal prognosis. Recently, several actionable genetic aberrations were identified with significant enrichment in intrahepatic CCA, including FGFR2 gene fusions with a prevalence of 10-15%. Recent clinical data demonstrate that these fusions are druggable in a second-line setting in advanced/metastatic disease and the efficacy in earlier lines of therapy is being evaluated in ongoing clinical trials. This scenario warrants standardised molecular profiling of these tumours. METHODS: A detailed analysis of the original genetic data from the FIGHT-202 trial, on which the approval of Pemigatinib was based, was conducted. RESULTS: Comparing different detection approaches and displaying representative cases, we described the genetic landscape and architecture of FGFR2 fusions in iCCA and show biological and technical aspects to be considered for their detection. We elaborated parameters, including a suggestion for annotation, that should be stated in a molecular diagnostic FGFR2 report to allow a complete understanding of the analysis performed and the information provided. CONCLUSION: This study provides a detailed presentation and dissection of the technical and biological aspects regarding FGFR2 fusion detection, which aims to support molecular pathologists, pathologists and clinicians in diagnostics, reporting of the results and decision-making.


Subject(s)
Bile Duct Neoplasms , Cholangiocarcinoma , Bile Duct Neoplasms/drug therapy , Bile Ducts, Intrahepatic/pathology , Cholangiocarcinoma/drug therapy , Genomics , Humans , Molecular Diagnostic Techniques , Receptor, Fibroblast Growth Factor, Type 2/genetics
5.
Skin Pharmacol Physiol ; 35(2): 77-86, 2022.
Article in English | MEDLINE | ID: mdl-34348349

ABSTRACT

INTRODUCTION: Bathing in the Blue Lagoon (BL) in Iceland benefits patients with psoriasis. Accordingly, the BL water contains algae with biological activities that improve skin barrier function and affect T-cell responses relevant for psoriasis. Bathing in the BL is also becoming increasingly popular among healthy individuals and anecdotal evidence suggests positive effects on uneven skin pigmentation. OBJECTIVE: The aim of the study was to address the impact of BL algae on skin pigmentation. METHODS: In this work, in vitro gene expression studies in melanocytes and a noninvasive in vivo study were conducted. RESULTS: We here report that normal human epidermal melanocytes, which had been treated with nontoxic concentrations of BL algae, show a significantly reduced expression of α melanocyte-stimulating hormone-induced expression of genes important for melanin synthesis, such as tyrosinase, tyrosinase-related protein 1, dopachrome tautomerase, melan A protein, and pre-melanosome protein. This in vitro observation prompted us to conduct a randomized, double-blind, intra-individual, comparative split-face in vivo study, in which 60 volunteers with pre-existing facial pigment spots were treated twice daily with a BL algae containing serum or a vehicle control. We found that constitutive skin pigmentation as determined by colorimetry (individual typology angle and luminescence) did not differ significantly between vehicle- and serum-treated skin sites. In marked contrast, digital photography under cross-polarized lighting and RBX technology (VISIA CR) revealed that the number of pigment spots in the serum-treated face decreased significantly compared to the vehicle-treated side. CONCLUSION: Thus, BL algae can affect human melanocyte function in vitro and reduce uneven facial skin pigmentation in vivo.


Subject(s)
Melanocytes , Skin Pigmentation , Double-Blind Method , Humans , Melanins/metabolism , Monophenol Monooxygenase/metabolism , Skin/metabolism
6.
Skin Pharmacol Physiol ; 34(3): 135-145, 2021.
Article in English | MEDLINE | ID: mdl-33789311

ABSTRACT

BACKGROUND: Oral supplementation with a standardized extract from the bark of the French pine (Pycnogenol®) has been reported to benefit the skin. It might thus represent an easy-to-use strategy to improve the skin health of individuals who are exposed to considerable environmental stress in large urban areas. OBJECTIVE: We investigated if oral intake of Pycnogenol® can benefit the skin of Han Chinese working outdoors in Beijing, China. METHODS: In a monocentre, double-blind, randomized, placebo-controlled, and crossover study, the effects of Pycnogenol® intake (2 × 50 mg/day for a total of 12 weeks) on a variety of skin physiological parameters was studied in Chinese subjects (n = 76), from spring to autumn, who were working outdoors in Beijing, China. RESULTS: During the intervention period, study subjects were constantly exposed to increased levels of particulate matter (PM)2.5 as well as seasonal changes in humidity and temperature. Despite this environmental stress, Pycnogenol® intake prevented (i) a decrease in the skin hydration, (ii) transepidermal water loss (TEWL), and (iii) skin darkening during the dry autumn season. In addition, Pycnogenol® intake improved (iv) viscoelastic skin properties such as gross elasticity and elastic recovery irrespective of the season. These beneficial effects were not observed if the same subjects were supplemented with placebo. CONCLUSION: Oral intake of Pycnogenol® benefits the skin in Han Chinese, who are working outdoors under considerable environmental stress.


Subject(s)
Antioxidants/pharmacology , Flavonoids/pharmacology , Plant Extracts/pharmacology , Skin/drug effects , China , Cross-Over Studies , Double-Blind Method , Humans , Occupational Diseases/drug therapy , Particulate Matter/analysis , Seasons , Skin/metabolism , Water/metabolism
7.
Br J Haematol ; 190(2): 189-197, 2020 07.
Article in English | MEDLINE | ID: mdl-32163180

ABSTRACT

Smouldering multiple myeloma (SMM) presents without MM defining symptoms. We aimed to identify patients with SMM with an 80% risk of progression within 2 years using only serum parameters. In total, 527 patients with SMM were included and divided into a training group (287 patients from the Czech Myeloma Group [CMG]) and an independent validation group (240 patients from Heidelberg). The median follow-up was 2·4 and 2·5 years, respectively. Progression to MM occurred in 51·9% of the CMG and 38·8% of the Heidelberg patients, respectively. The median risk of progression was 11·0% (CMG) and 9·7% (Heidelberg) per year, during the 5 years after diagnosis. A serum involved/uninvolved free light-chain ratio of >30, immunoparesis, and serum monoclonal (M) protein of ≥2·3 g/dl emerged as powerful predictors of 2-year progression rate with a hazard ratio (HR) of 2·49 (95% confidence interval [CI] 1·49-4·17), HR of 2·01 (95% CI 1·36-2·96) and HR of 2·00 (95% CI 1·44-2·79) (P < 0·001) in univariate Cox regression analysis, respectively. Based on this, the CMG model identified patients with SMM with a 2-year risk of progression of 78·7% (95% CI 53·1-95·7; HR 6·8; P < 0·001, CMG) and 81·3% (95% CI 47·1-98·8; HR 38·63; P < 0·001, Heidelberg). Serum parameters in the CMG model allow identification of patients with SMM with an 80% risk of progression to symptomatic MM within 2 years.


Subject(s)
Smoldering Multiple Myeloma/diagnosis , Adult , Aged , Aged, 80 and over , Czech Republic , Disease Progression , Female , Humans , Male , Middle Aged , Risk Factors , Smoldering Multiple Myeloma/pathology
8.
J Med Ethics ; 2020 Apr 03.
Article in English | MEDLINE | ID: mdl-32245804

ABSTRACT

Making good decisions in extremely complex and difficult processes and situations has always been both a key task as well as a challenge in the clinic and has led to a large amount of clinical, legal and ethical routines, protocols and reflections in order to guarantee fair, participatory and up-to-date pathways for clinical decision-making. Nevertheless, the complexity of processes and physical phenomena, time as well as economic constraints and not least further endeavours as well as achievements in medicine and healthcare continuously raise the need to evaluate and to improve clinical decision-making. This article scrutinises if and how clinical decision-making processes are challenged by the rise of so-called artificial intelligence-driven decision support systems (AI-DSS). In a first step, this article analyses how the rise of AI-DSS will affect and transform the modes of interaction between different agents in the clinic. In a second step, we point out how these changing modes of interaction also imply shifts in the conditions of trustworthiness, epistemic challenges regarding transparency, the underlying normative concepts of agency and its embedding into concrete contexts of deployment and, finally, the consequences for (possible) ascriptions of responsibility. Third, we draw first conclusions for further steps regarding a 'meaningful human control' of clinical AI-DSS.

9.
Skin Res Technol ; 26(4): 558-563, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31919922

ABSTRACT

BACKGROUND: The decontamination of the skin is indispensable if airborne particulate contaminants deposit on the skin surface. Skin washing can have adverse effects as by skin rubbing the particles can be transferred deeply into the hair follicles, where they can be entrapped for a period of more than 10 days. Thus, alternative skin decontamination strategies are necessary. MATERIALS AND METHODS: For imaging the contaminants in the skin, sodium fluorescein-labeled soot particles of submicron size (≈600 nm) were visualized using laser scanning microscopy. RESULTS: In the present ex vivo pilot study on porcine ear skin, it was shown that sodium fluorescein-labeled soot particles of submicron size (≈600 nm) could be efficiently removed from the skin with highly absorbent textile nanofiber material, whose efficacy could be further increased by spraying the contaminated skin area with the viscous fluid PEG-12 dimethicone before textile application. CONCLUSION: In case of skin contamination with particulates, the contact washing should be avoided due to rubbing particles deeply into the hair follicles, where they can accumulate for a long time and induce negative consequences. Efficient skin decontamination could include pretreatment of skin surface with the viscous fluid PEG-12 dimethicone and subsequent application of highly absorbent textile nanofiber material.


Subject(s)
Decontamination , Nanofibers , Particulate Matter , Skin Care , Textiles , Animals , Dimethylpolysiloxanes , Microscopy, Confocal , Particulate Matter/analysis , Pilot Projects , Skin Care/methods , Skin Physiological Phenomena/drug effects , Swine
10.
Skin Pharmacol Physiol ; 33(1): 9-16, 2020.
Article in English | MEDLINE | ID: mdl-31509849

ABSTRACT

INTRODUCTION: Skin ageing involves senescent fibroblast accumulation, disturbance in extracellular matrix (ECM) homeostasis, and decreased collagen synthesis. OBJECTIVE: to assess a cell therapy product for aged skin (RCS-01; verum) consisting of ~25 × 106 cultured, autologous cells derived from anagen hair follicle non-bulbar dermal sheath (NBDS). METHODS: For each subject in the verum group, 4 areas of buttock skin were injected intradermally 1 or 3 times at monthly intervals with RCS-01, cryomedium, or needle penetration without injection; in the placebo group RCS-01 was replaced by cryomedium. The primary endpoint was assessment of local adverse event profiles. As secondary endpoints, expression of genes related to ECM homeostasis was assessed in biopsies from randomly selected volunteers in the RCS-01 group taken 4 weeks after the last injection. -Results: Injections were well tolerated with no severe adverse events reported 1 year after the first injection. When compared with placebo-treated skin, a single treatment with RCS-01 resulted in a significant upregulation of TGFß1, CTGF, COL1A1, COL1A2, COL3A1, and lumican mRNA expression. LIMITATIONS: The cohort size was insufficient for dose -ranging evaluation and subgroup analyses of efficacy. CONCLUSIONS: RCS-01 therapy is well tolerated and associated with a gene expression response consistent with an improvement of ECM homeostasis.


Subject(s)
Cell- and Tissue-Based Therapy , Hair Follicle/cytology , Skin Aging , Collagen Type I/genetics , Collagen Type I, alpha 1 Chain , Collagen Type III/genetics , Connective Tissue Growth Factor/genetics , Double-Blind Method , Female , Gene Expression Regulation , Humans , Male , Middle Aged , Skin Aging/genetics , Transcriptome , Transforming Growth Factor beta1/genetics , Transplantation, Autologous
12.
Skin Pharmacol Physiol ; 32(2): 101-108, 2019.
Article in English | MEDLINE | ID: mdl-30836363

ABSTRACT

BACKGROUND: Our previous double-blinded, placebo-controlled cross-over study indicated that a nutritional supplement named lycopene-rich tomato nutrient complex (TNC) can protect from UVA1-induced (340-400 nm) and UVA- (320-400 nm)/UVB-induced (280-320 nm) upregulation of molecular markers associated with oxidative stress, inflammation, and ageing. OBJECTIVES: in the current double-blind, randomized, placebo-controlled multicenter study, we analyze whether a similar, synergistic carotenoid-rich TNC can protect from broadband UVB-induced threshold erythema formation assessed as increase in minimal erythemal dose (MED) reading, the intensity of erythema formation, and the upregulation of molecular markers associated with inflammation and immunosuppression, and whether this correlates with carotenoid blood levels. METHODS: One hundred and forty-nine healthy volunteers were randomized to two groups and subjected to a 5-week washout phase, followed by a 12-week treatment phase receiving either 15 mg lycopene, 5.8 mg phytoene and phytofluene, 0.8 mg ß-carotene, 5.6 mg tocopherols from tomato extract, and 4 mg carnosic acid from rosemary extract per day or placebo made from medium-chain triglycerides. At the end of each phase, MED determination, UVB irradiation, chromametry, biopsies, and blood samples were undertaken. RESULTS: The active supplement was well tolerated. Interestingly, no significant difference was seen in the MED between the active-supplement and placebo groups, as determined by visual grading by expert assessors. Of note, the carotenoid-containing supplement significantly protected against UVB-induced erythema formation measured as Δa* after the intervention minus Δa* after the washout phase as compared to the placebo. Moreover, intake of the active supplement significantly protected against UVB-induced upregulation of IL6 and TNFα as compared with the intake of placebo. Lastly, carotenoid plasma levels were significantly increased. CONCLUSION: This well-tolerated carotenoid-containing supplement significantly protected against UVB-induced erythema formation and upregulation of proinflammatory cytokines in healthy volunteers.


Subject(s)
Antioxidants/pharmacology , Carotenoids/pharmacology , Dietary Supplements , Erythema/prevention & control , Phytochemicals/pharmacology , Radiation-Protective Agents/pharmacology , Solanum lycopersicum/chemistry , Ultraviolet Rays/adverse effects , Adult , Cytokines/genetics , Double-Blind Method , Erythema/genetics , Female , Gene Expression Regulation/drug effects , Gene Expression Regulation/radiation effects , Humans , Male , Middle Aged , Skin/drug effects , Skin/metabolism , Skin/radiation effects , Young Adult
14.
Hum Mol Genet ; 24(19): 5486-99, 2015 Oct 01.
Article in English | MEDLINE | ID: mdl-26188004

ABSTRACT

Mutations in the PDE6A gene can cause rod photoreceptors degeneration and the blinding disease retinitis pigmentosa (RP). While a number of pathogenic PDE6A mutations have been described, little is known about their impact on compound heterozygous situations and potential interactions of different disease-causing alleles. Here, we used a novel mouse model for the Pde6a R562W mutation in combination with an existing line carrying the V685M mutation to generate compound heterozygous Pde6a V685M/R562W animals, exactly homologous to a case of human RP. We compared the progression of photoreceptor degeneration in these compound heterozygous mice with the homozygous V685M and R562W mutants, and additionally with the D670G line that is known for a relatively mild phenotype. We investigated PDE6A expression, cyclic guanosine mono-phosphate accumulation, calpain and caspase activity, in vivo retinal function and morphology, as well as photoreceptor cell death and survival. This analysis confirms the severity of different Pde6a mutations and indicates that compound heterozygous mutants behave like intermediates of the respective homozygous situations. Specifically, the severity of the four different Pde6a situations may be categorized by the pace of photoreceptor degeneration: V685M (fastest) > V685M/R562W > R562W > D670G (slowest). While calpain activity was strongly increased in all four mutants, caspase activity was not. This points to the execution of non-apoptotic cell death and may lead to the identification of new targets for therapeutic interventions. For individual RP patients, our study may help to predict time-courses for Pde6a-related retinal degeneration and thereby facilitate the definition of a window-of-opportunity for clinical interventions.


Subject(s)
Cyclic Nucleotide Phosphodiesterases, Type 6/genetics , Cyclic Nucleotide Phosphodiesterases, Type 6/metabolism , Eye Proteins/genetics , Eye Proteins/metabolism , Point Mutation , Retina/physiopathology , Retinitis Pigmentosa/pathology , Animals , Calpain/metabolism , Caspases/metabolism , Cell Survival , Disease Models, Animal , Humans , Mice , Retina/metabolism , Retina/pathology , Retinal Rod Photoreceptor Cells/cytology , Retinal Rod Photoreceptor Cells/pathology , Retinitis Pigmentosa/genetics , Retinitis Pigmentosa/metabolism , Retinitis Pigmentosa/physiopathology
15.
J Drugs Dermatol ; 16(8): s125-s128, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28810000

ABSTRACT

There is compelling evidence that Infrared A (IRA) from natural sunlight contributes to photoaging of human skin by inducing the expression of matrix metalloproteinase-1 (MMP-1) expression in human dermal fibroblasts. Corresponding mechanistic studies have shown that IRA does so by increasing the production of reactive oxygen species in irradiated cells. In the present study, we therefore asked if treatment of primary human skin fibroblasts with a blueberry-derived antioxidant matrix (BerrimatrixTM), which is employed as an active ingredient in commercially available skin care products that are topically applied, can prevent IRA-induced MMP-1 expression in these cells. In this in vitro study, we have found that this antioxidant containing matrix is well tolerated by fibroblast over a broad concentration range and that it efficiently prevents IRA-induced MMP-1 mRNA expression. It may thus be speculated that topical application of this antioxidant containing matrix may be efficient in protecting human skin against IRA-induced wrinkle formation.

J Drugs Dermatol. 2017;16(8 Suppl 2):s125-128.

.


Subject(s)
Antioxidants/pharmacology , Blueberry Plants , Fibroblasts/drug effects , Skin/drug effects , Cell Survival , Cells, Cultured/drug effects , Cells, Cultured/enzymology , Cells, Cultured/radiation effects , Fibroblasts/enzymology , Fibroblasts/radiation effects , Gene Expression Regulation/drug effects , Gene Expression Regulation/radiation effects , Humans , Infrared Rays , Matrix Metalloproteinase 1/metabolism , Plant Extracts/chemistry , Skin/radiation effects
16.
J Biol Chem ; 290(16): 10242-55, 2015 Apr 17.
Article in English | MEDLINE | ID: mdl-25739440

ABSTRACT

Phosphodiesterase-6 (PDE6) is a multisubunit enzyme that plays a key role in the visual transduction cascade in rod and cone photoreceptors. Each type of photoreceptor utilizes discrete catalytic and inhibitory PDE6 subunits to fulfill its physiological tasks, i.e. the degradation of cyclic guanosine-3',5'-monophosphate at specifically tuned rates and kinetics. Recently, the human PDE6H gene was identified as a novel locus for autosomal recessive (incomplete) color blindness. However, the three different classes of cones were not affected to the same extent. Short wave cone function was more preserved than middle and long wave cone function indicating that some basic regulation of the PDE6 multisubunit enzyme was maintained albeit by a unknown mechanism. To study normal and disease-related functions of cone Pde6h in vivo, we generated Pde6h knock-out (Pde6h(-/-)) mice. Expression of PDE6H in murine eyes was restricted to both outer segments and synaptic terminals of short and long/middle cone photoreceptors, whereas Pde6h(-/-) retinae remained PDE6H-negative. Combined in vivo assessment of retinal morphology with histomorphological analyses revealed a normal overall integrity of the retinal organization and an unaltered distribution of the different cone photoreceptor subtypes upon Pde6h ablation. In contrast to human patients, our electroretinographic examinations of Pde6h(-/-) mice suggest no defects in cone/rod-driven retinal signaling and therefore preserved visual functions. To this end, we were able to demonstrate the presence of rod PDE6G in cones indicating functional substitution of PDE6. The disparities between human and murine phenotypes caused by mutant Pde6h/PDE6H suggest species-to-species differences in the vulnerability of biochemical and neurosensory pathways of the visual signal transduction system.


Subject(s)
Cyclic Nucleotide Phosphodiesterases, Type 6/genetics , Light Signal Transduction/genetics , Protein Subunits/genetics , Retinal Cone Photoreceptor Cells/metabolism , Retinal Rod Photoreceptor Cells/metabolism , 3',5'-Cyclic-GMP Phosphodiesterases , Animals , Color Vision Defects/genetics , Color Vision Defects/metabolism , Color Vision Defects/pathology , Cyclic GMP/metabolism , Cyclic Nucleotide Phosphodiesterases, Type 6/metabolism , Electroretinography , Gene Deletion , Gene Expression , Humans , Mice , Mice, Knockout , Protein Isoforms/deficiency , Protein Isoforms/genetics , Protein Subunits/metabolism , Retinal Cone Photoreceptor Cells/cytology , Retinal Rod Photoreceptor Cells/cytology , Signal Transduction , Species Specificity
17.
Hum Mol Genet ; 23(13): 3384-401, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24493795

ABSTRACT

In humans, the Crumbs homolog-1 (CRB1) gene is mutated in autosomal recessive Leber congenital amaurosis and early-onset retinitis pigmentosa. In mammals, the Crumbs family is composed of: CRB1, CRB2, CRB3A and CRB3B. Recently, we showed that removal of mouse Crb2 from retinal progenitor cells, and consequent removal from Müller glial and photoreceptor cells, results in severe and progressive retinal degeneration with concomitant loss of retinal function that mimics retinitis pigmentosa due to mutations in the CRB1 gene. Here, we studied the effects of cell-type-specific loss of CRB2 from the developing mouse retina using targeted conditional deletion of Crb2 in photoreceptors or Müller cells. We analyzed the consequences of targeted loss of CRB2 in the adult mouse retina using adeno-associated viral vectors encoding Cre recombinase and short hairpin RNA against Crb2. In vivo retinal imaging by means of optical coherence tomography on retinas lacking CRB2 in photoreceptors showed progressive thinning of the photoreceptor layer and cellular mislocalization. Electroretinogram recordings under scotopic conditions showed severe attenuation of the a-wave, confirming the degeneration of photoreceptors. Retinas lacking CRB2 in developing photoreceptors showed early onset of abnormal lamination, whereas retinas lacking CRB2 in developing Müller cells showed late onset retinal disorganization. Our data suggest that in the developing retina, CRB2 has redundant functions in Müller glial cells, while CRB2 has essential functions in photoreceptors. Our data suggest that short-term loss of CRB2 in adult mouse photoreceptors, but not in Müller glial cells, causes sporadic loss of adhesion between photoreceptors and Müller cells.


Subject(s)
Membrane Proteins/metabolism , Photoreceptor Cells/metabolism , Retinitis Pigmentosa/etiology , Retinitis Pigmentosa/metabolism , Animals , Ependymoglial Cells/metabolism , Female , Immunohistochemistry , Male , Membrane Proteins/genetics , Mice, Inbred C57BL , Mice, Knockout , Retinitis Pigmentosa/genetics
18.
PLoS Genet ; 9(12): e1003976, 2013.
Article in English | MEDLINE | ID: mdl-24339791

ABSTRACT

Development in the central nervous system is highly dependent on the regulation of the switch from progenitor cell proliferation to differentiation, but the molecular and cellular events controlling this process remain poorly understood. Here, we report that ablation of Crb1 and Crb2 genes results in severe impairment of retinal function, abnormal lamination and thickening of the retina mimicking human Leber congenital amaurosis due to loss of CRB1 function. We show that the levels of CRB1 and CRB2 proteins are crucial for mouse retinal development, as they restrain the proliferation of retinal progenitor cells. The lack of these apical proteins results in altered cell cycle progression and increased number of mitotic cells leading to an increased number of late-born cell types such as rod photoreceptors, bipolar and Müller glia cells in postmitotic retinas. Loss of CRB1 and CRB2 in the retina results in dysregulation of target genes for the Notch1 and YAP/Hippo signaling pathways and increased levels of P120-catenin. Loss of CRB1 and CRB2 result in altered progenitor cell cycle distribution with a decrease in number of late progenitors in G1 and an increase in S and G2/M phase. These findings suggest that CRB1 and CRB2 suppress late progenitor pool expansion by regulating multiple proliferative signaling pathways.


Subject(s)
Central Nervous System/metabolism , Leber Congenital Amaurosis/genetics , Membrane Proteins/biosynthesis , Nerve Tissue Proteins/biosynthesis , Retina/growth & development , Animals , Cell Cycle/genetics , Cell Differentiation/genetics , Cell Proliferation , Central Nervous System/growth & development , Central Nervous System/pathology , Disease Models, Animal , Gene Expression Regulation, Developmental , Humans , Leber Congenital Amaurosis/metabolism , Leber Congenital Amaurosis/pathology , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/genetics , Mice , Mitosis/genetics , Nerve Tissue Proteins/antagonists & inhibitors , Nerve Tissue Proteins/genetics , Retina/cytology , Retina/metabolism , Retinal Degeneration/genetics , Retinal Degeneration/pathology , Retinal Rod Photoreceptor Cells/metabolism , Retinal Rod Photoreceptor Cells/pathology , Stem Cells/metabolism
19.
Skin Pharmacol Physiol ; 29(1): 13-7, 2016.
Article in English | MEDLINE | ID: mdl-26492562

ABSTRACT

Nutritional strategies to benefit skin health are of growing importance. Current approaches mainly involve nutritional supplements containing antioxidants which were initially designed to protect human skin against ultraviolet radiation-induced damage. Within recent years, however, a growing number of studies suggests that the beneficial effects of these products clearly extend beyond photoprotection. In this review we take the nutritional supplement Pycnogenol®, which is based on an extract prepared from French marine pine bark extract, as an example to illustrate this development. Accordingly, the existing data provide compelling evidence that Pycnogenol® intake does not only provide photoprotection, but may be used to (i) reduce hyperpigmentation of human skin and (ii) improve skin barrier function and extracellular matrix homeostasis.


Subject(s)
Flavonoids/pharmacology , Pinus , Plant Extracts/pharmacology , Sunscreening Agents/pharmacology , Animals , Dietary Supplements , Humans , Plant Bark , Skin/drug effects , Skin/metabolism , Skin Pigmentation/drug effects
20.
Hum Mol Genet ; 22(1): 35-50, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23001562

ABSTRACT

In humans, the Crumbs homolog-1 (CRB1) gene is mutated in progressive types of autosomal recessive retinitis pigmentosa and Leber congenital amaurosis. However, there is no clear genotype-phenotype correlation for CRB1 mutations, which suggests that other components of the CRB complex may influence the severity of retinal disease. Therefore, to understand the physiological role of the Crumbs complex proteins, we generated and analysed conditional knockout mice lacking CRB2 in the developing retina. Progressive disorganization was detected during late retinal development. Progressive thinning of the photoreceptor layer and sites of cellular mislocalization was detected throughout the CRB2-deficient retina by confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography. Under scotopic conditions using electroretinography, the attenuation of the a-wave was relatively stronger than that of the b-wave, suggesting progressive degeneration of photoreceptors in adult animals. Histological analysis of newborn mice showed abnormal lamination of immature rod photoreceptors and disruption of adherens junctions between photoreceptors, Müller glia and progenitor cells. The number of late-born progenitor cells, rod photoreceptors and Müller glia cells was increased, concomitant with programmed cell death of rod photoreceptors. The data suggest an essential role for CRB2 in proper lamination of the photoreceptor layer and suppression of proliferation of late-born retinal progenitor cells.


Subject(s)
Eye Proteins/genetics , Membrane Proteins/genetics , Mutation , Nerve Tissue Proteins/genetics , Retina/metabolism , Retinitis Pigmentosa/genetics , Animals , Apoptosis , Base Sequence , DNA Primers , Electroretinography , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Photoreceptor Cells, Vertebrate/pathology , Polymerase Chain Reaction , Retina/growth & development , Retinitis Pigmentosa/pathology , Tomography, Optical Coherence
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