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1.
Int J Mol Sci ; 25(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38542418

RESUMO

Inherited retinal degenerative diseases (IRDs) are a group of rare diseases that lead to a progressive loss of photoreceptor cells and, ultimately, blindness. The overactivation of cGMP-dependent protein kinase G (PKG), one of the key effectors of cGMP-signaling, was previously found to be involved in photoreceptor cell death and was studied in murine IRD models to elucidate the pathophysiology of retinal degeneration. However, PKG is a serine/threonine kinase (STK) with several hundred potential phosphorylation targets and, so far, little is known about the specificity of the target interaction and downstream effects of PKG activation. Here, we carried out both the kinome activity and phosphoproteomic profiling of organotypic retinal explant cultures derived from the rd10 mouse model for IRD. After treating the explants with the PKG inhibitor CN03, an overall decrease in peptide phosphorylation was observed, with the most significant decrease occurring in seven peptides, including those from the known PKG substrate cyclic-AMP-response-element-binding CREB, but also Ca2+/calmodulin-dependent kinase (CaMK) peptides and TOP2A. The phosphoproteomic data, in turn, revealed proteins with decreased phosphorylation, as well as proteins with increased phosphorylation. The integration of both datasets identified common biological networks altered by PKG inhibition, which included kinases predominantly from the so-called AGC and CaMK families of kinases (e.g., PKG1, PKG2, PKA, CaMKs, RSKs, and AKTs). A pathway analysis confirmed the role of CREB, Calmodulin, mitogen-activated protein kinase (MAPK) and CREB modulation. Among the peptides and pathways that showed reduced phosphorylation activity, the substrates CREB, CaMK2, and CaMK4 were validated for their retinal localization and activity, using immunostaining and immunoblotting in the rd10 retina. In summary, the integrative analysis of the kinome activity and phosphoproteomic data revealed both known and novel PKG substrates in a murine IRD model. This data establishes a basis for an improved understanding of the biological pathways involved in cGMP-mediated photoreceptor degeneration. Moreover, validated PKG targets like CREB and CaMKs merit exploration as novel (surrogate) biomarkers to determine the effects of a clinical PKG-targeted treatment for IRDs.


Assuntos
Degeneração Retiniana , Animais , Camundongos , Fosforilação , Degeneração Retiniana/metabolismo , Calmodulina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Retina/metabolismo , GMP Cíclico/metabolismo
2.
Adv Exp Med Biol ; 1415: 479-483, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440075

RESUMO

Retinitis pigmentosa (RP) is an inherited disorder that results in vision impairment that specific therapeutic strategies are not available. However, it is widely regarded that the cGMP system, including cGMP and its interactor cGMP-dependent protein kinase (PKG), acts as a crucial effector during retinal degeneration. We have previously identified a list of cGMP-PKG-dependent genes in the context of RP, and in this study, we further validated one of the targets, namely, pyruvate kinase 2 (PKM2), and investigated the potential role of PKM2 for the photoreceptors' well-being during RP. With the aid of organotypic retinal explant cultures, we pharmacologically manipulated the PKM2 activities in different RP mouse models via the addition of TEPP-46 (a PKM2 activator) and found that activation of PKM2 alleviates the progress of photoreceptor death in the rd10 mouse model. This observation provides supportive evidence that PKM2 may serve as a novel potential molecular target in RP.


Assuntos
Degeneração Retiniana , Retinose Pigmentar , Camundongos , Animais , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo , Retina/metabolismo , Células Fotorreceptoras/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
3.
Int J Mol Sci ; 24(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37372984

RESUMO

Retinitis pigmentosa (RP) is a frequent cause of blindness among the working population in industrial countries due to the inheritable death of photoreceptors. Though gene therapy was recently approved for mutations in the RPE65 gene, there is in general no effective treatment presently. Previously, abnormally high levels of cGMP and overactivation of its dependent protein kinase (PKG) have been suggested as causative for the fatal effects on photoreceptors, making it meaningful to explore the cGMP-PKG downstream signaling for more pathological insights and novel therapeutic target development purposes. Here, we manipulated the cGMP-PKG system in degenerating retinas from the rd1 mouse model pharmacologically via adding a PKG inhibitory cGMP-analogue to organotypic retinal explant cultures. A combination of phosphorylated peptide enrichment and mass spectrometry was then applied to study the cGMP-PKG-dependent phosphoproteome. We identified a host of novel potential cGMP-PKG downstream substrates and related kinases using this approach and selected the RAF1 protein, which may act as both a substrate and a kinase, for further validation. This showed that the RAS/RAF1/MAPK/ERK pathway may be involved in retinal degeneration in a yet unclarified mechanism, thus deserving further investigation in the future.


Assuntos
Degeneração Retiniana , Retinose Pigmentar , Camundongos , Animais , Degeneração Retiniana/patologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Retina/metabolismo , Retinose Pigmentar/metabolismo , Transdução de Sinais
4.
Int J Mol Sci ; 23(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35563009

RESUMO

The disease retinitis pigmentosa (RP) leads to photoreceptor degeneration by a yet undefined mechanism(s). In several RP mouse models (i.e., rd mice), a high cyclic GMP (cGMP) level within photoreceptors is detected, suggesting that cGMP plays a role in degeneration. The rap guanine exchange factor 4 (EPAC2) is activated by cyclic AMP (cAMP) and is an accepted cGMP-interacting protein. It is unclear whether and how cGMP interacts with EPAC2 in degenerating photoreceptors; we therefore investigated EPAC2 expression and interactions with cGMP and cAMP in retinas of the rd1 and rd10 models for retinal degeneration. EPAC2 expression in the photoreceptor layer increased significantly during rd1 and rd10 degeneration, and an increase in EPAC2 interactions with cGMP but not cAMP in the rd1 was also seen via a proximity ligation assay on histological sections. Retinal explant cultures revealed that pharmacological inhibition of the EPAC2 activity reduced the photoreceptor layer thickness in the rd10 retina, suggesting that EPAC2 inhibition promotes degeneration. Taken together, our results support the hypothesis that high degeneration-related cGMP leads to increased EPAC2 and cGMP interactions, inhibiting EPAC2. By inference, EPAC2 could have neuroprotective capacities that may be exploited in the future.


Assuntos
Degeneração Retiniana , Retinose Pigmentar , Animais , GMP Cíclico/metabolismo , Modelos Animais de Doenças , Guanina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Retina/metabolismo , Degeneração Retiniana/metabolismo , Retinose Pigmentar/metabolismo
5.
J Neurochem ; 157(6): 2173-2186, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33230839

RESUMO

The hereditary disease Retinitis pigmentosa results in severe vision loss due to photoreceptor degeneration by unclear mechanisms. In several disease models, the second messenger cGMP accumulates in the degenerating photoreceptors, where it may over-activate specific cGMP-interacting proteins, like cGMP-dependent protein kinase. Moreover, interventions that counteract the activity of these proteins lead to reduced photoreceptor cell death. Yet there is little or no information whether other than such regular cGMP-interactors are present in the retina, which we, therefore, investigated in wild-type and retinal degeneration (rd1, rd10, and rd2) mouse models. An affinity chromatography based proteomics approach that utilized immobilized cGMP analogs was applied to enrich and select for regular and potentially new cGMP-interacting proteins as identified by mass spectrometry. This approach revealed 12 regular and 10 potentially new retinal cGMP-interacting proteins (e.g., EPAC2 and CaMKIIα). Several of the latter were found to be expressed in the photoreceptors and to have proximity to cGMP and may thus be of interest when defining prospective therapeutic targets or biomarkers for retinal degeneration.


Assuntos
GMP Cíclico/genética , GMP Cíclico/metabolismo , Proteômica/métodos , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Retina/metabolismo , Retina/patologia , Degeneração Retiniana/patologia
6.
Exp Eye Res ; 212: 108752, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34478738

RESUMO

Retinitis Pigmentosa represents a group of genetic disorders that cause progressive vision loss via degeneration of photoreceptors, but there is in principle no treatment available. For any therapy development, a deeper comprehension of the disease-leading mechanism(s) at the molecular level is needed. Here we focused on the cGMP-PKG system, which has been suggested to be a driver in several models of the disease. To gain insights in its downstream signaling we manipulated the cGMP-PKG system with the aid of organotypic retinal explant cultures from either a mouse-based disease model, i.e. the rd1 mouse, or its healthy wild-type counterpart (wt), by adding different types of cGMP analogues to either inhibit or activate PKG in retinal explants from rd1 and wt, respectively. An RNA sequencing was then performed to study the cGMP-PKG dependent transcriptome. Expression changes of gene sets related to specific pathways or functions, that fulfilled criteria involving that the changes should match PKG activation and inhibition, were determined via bioinformatics. The analyses highlighted that several gene sets linked to oxidative phosphorylation and mitochondrial pathways were regulated by this enzyme system. Specifically, the expression of such pathway components was upregulated in the rd1 treated with PKG inhibitor and downregulated in the wt with PKG activator treatment, suggesting that cGMP-PKG act as a negative regulator in this context. Downregulation of energy production pathways may thus play an integral part in the mechanism behind the degeneration for at least several RP mutations.


Assuntos
GMP Cíclico/genética , DNA/genética , Mutação , Proteínas Quinases/genética , Retina/metabolismo , Retinose Pigmentar/genética , Transcriptoma/genética , Animais , Células Cultivadas , GMP Cíclico/metabolismo , Análise Mutacional de DNA , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C3H , Proteínas Quinases/metabolismo , Retina/patologia , Degeneração Retiniana , Retinose Pigmentar/metabolismo , Retinose Pigmentar/patologia , Transdução de Sinais
7.
Proc Natl Acad Sci U S A ; 115(13): E2997-E3006, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29531030

RESUMO

Inherited retinal degeneration (RD) is a devastating and currently untreatable neurodegenerative condition that leads to loss of photoreceptor cells and blindness. The vast genetic heterogeneity of RD, the lack of "druggable" targets, and the access-limiting blood-retinal barrier (BRB) present major hurdles toward effective therapy development. Here, we address these challenges (i) by targeting cGMP (cyclic guanosine- 3',5'-monophosphate) signaling, a disease driver common to different types of RD, and (ii) by combining inhibitory cGMP analogs with a nanosized liposomal drug delivery system designed to facilitate transport across the BRB. Based on a screen of several cGMP analogs we identified an inhibitory cGMP analog that interferes with activation of photoreceptor cell death pathways. Moreover, we found liposomal encapsulation of the analog to achieve efficient drug targeting to the neuroretina. This pharmacological treatment markedly preserved in vivo retinal function and counteracted photoreceptor degeneration in three different in vivo RD models. Taken together, we show that a defined class of compounds for RD treatment in combination with an innovative drug delivery method may enable a single type of treatment to address genetically divergent RD-type diseases.


Assuntos
Barreira Hematorretiniana/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/administração & dosagem , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Degeneração Retiniana/tratamento farmacológico , Animais , Barreira Hematorretiniana/efeitos dos fármacos , GMP Cíclico/farmacologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Lipossomos , Camundongos , Células Fotorreceptoras/metabolismo , Retina/efeitos dos fármacos , Retina/metabolismo , Degeneração Retiniana/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Adv Exp Med Biol ; 1185: 245-249, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884619

RESUMO

Many RD-causing mutations lead to a dysregulation of cyclic guanosine monophosphate (cGMP), making cGMP signalling a prime target for the development of new treatment approaches. We showed previously that an analogue of cGMP, which inhibited cGMP signalling targets, increased photoreceptor viability in three rodent RD models carrying different genetic defects, in different RD genes. This raises the question of the possible generality of this approach as a treatment for RD. Here, we review RD genes that can be associated with high cGMP and discuss which RD genes might be amenable to a treatment aimed at inhibiting excessive cGMP signalling.


Assuntos
GMP Cíclico/química , Células Fotorreceptoras de Vertebrados/química , Degeneração Retiniana/genética , Transdução de Sinais , Animais , Mutação
9.
BMC Med Genet ; 19(1): 26, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29458332

RESUMO

BACKGROUND: The genetic mechanisms for families who meet the clinical criteria for Lynch syndrome (LS) but do not carry pathogenic variants in the mismatch repair (MMR) genes are still undetermined. We aimed to study the potential contribution of genes other than MMR genes to the biological and clinical characteristics of Norwegian families fulfilling Amsterdam (AMS) criteria or revised Bethesda guidelines. METHODS: The Hereditary Cancer Biobank of the Norwegian Radium Hospital was interrogated to identify individuals with a high risk of developing colorectal cancer (CRC) for whom no pathogenic variants in MMR genes had been found in routine diagnostic DNA sequencing. Forty-four cancer susceptibility genes were selected and analyzed by using our in-house designed TruSeq amplicon-based assay for targeted sequencing. RNA splicing- and protein-dedicated in silico analyses were performed for all variants of unknown significance (VUS). Variants predicted as likely to affect splicing were experimentally analyzed by resorting to minigene assays. RESULTS: We identified a patient who met the revised Bethesda guidelines and carried a likely pathogenic variant in CHEK2 (c.470 T > C, p.I157T). In addition, 25 unique VUS were identified in 18 individuals, of which 2 exonic variants (MAP3K1 c.764A > G and NOTCH3 c.5854G >A) were analyzed in the minigene splicing assay and found not to have an effect on RNA splicing. CONCLUSIONS: Among high-risk CRC patients that fulfill the AMS criteria or revised Bethesda guidelines, targeted gene sequencing identified likely pathogenic variant and VUS in other genes than the MMR genes (CHEK2, NOTCH3 and MAP3K1). Our study suggests that the analysis of genes currently excluded from routine molecular diagnostic screens may confer cancer susceptibility.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Variação Genética , Adulto , Quinase do Ponto de Checagem 2/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Reparo de Erro de Pareamento de DNA , Éxons , Feminino , Predisposição Genética para Doença , Humanos , MAP Quinase Quinase Quinase 1/genética , Masculino , Noruega , Splicing de RNA , Receptor Notch3/genética , Análise de Sequência de DNA
10.
Artigo em Inglês | MEDLINE | ID: mdl-29371908

RESUMO

BACKGROUND: In kindreds carrying path_BRCA1/2 variants, some women in these families will develop cancer despite testing negative for the family's pathogenic variant. These families may have additional genetic variants, which not only may increase the susceptibility of the families' path_BRCA1/2, but also be capable of causing cancer in the absence of the path_BRCA1/2 variants. We aimed to identify novel genetic variants in prospectively detected breast cancer (BC) or gynecological cancer cases tested negative for their families' pathogenic BRCA1/2 variant (path_BRCA1 or path_BRCA2). METHODS: Women with BC or gynecological cancer who had tested negative for path_BRCA1 or path_BRCA2 variants were included. Forty-four cancer susceptibility genes were screened for genetic variation through a targeted amplicon-based sequencing assay. Protein- and RNA splicing-dedicated in silico analyses were performed for all variants of unknown significance (VUS). Variants predicted as the ones most likely affecting pre-mRNA splicing were experimentally analyzed in a minigene assay. RESULTS: We identified 48 women who were tested negative for their family's path_BRCA1 (n = 13) or path_BRCA2 (n = 35) variants. Pathogenic variants in the ATM, BRCA2, MSH6 and MUTYH genes were found in 10% (5/48) of the cases, of whom 15% (2/13) were from path_BRCA1 and 9% (3/35) from path_BRCA2 families. Out of the 26 unique VUS, 3 (12%) were predicted to affect RNA splicing (APC c.721G > A, MAP3K1 c.764A > G and MSH2 c.815C > T). However, by using a minigene, assay we here show that APC c.721G > A does not cause a splicing defect, similarly to what has been recently reported for the MAP3K1 c.764A > G. The MSH2 c.815C > T was previously described as causing partial exon skipping and it was identified in this work together with the path_BRCA2 c.9382C > T (p.R3128X). CONCLUSION: All women in breast or breast/ovarian cancer kindreds would benefit from being offered genetic testing irrespective of which causative genetic variants have been demonstrated in their relatives.

11.
BMC Cancer ; 17(1): 406, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592327

RESUMO

BACKGROUND: The prognostic significance of free cancer cells detected in peritoneal fluid at the time of rectal surgery remains unclear. A substantial number of patients will develop metastatic disease even with successful local treatment. This prospective non-randomized study investigated the prognostic value of intraperitoneal free cancer cells harvested in peritoneal lavage after surgery for rectal cancer. Mutational hotspots in mitochondrial DNA were examined as potential molecular signatures to detect circulating intraperitoneal free cancer cells when present in primary tumor and in lavage. METHODS: Point mutations in mitochondrial DNA amplifications were determined in primary tumors and corresponding exfoliated intraperitoneal free cancer cells in lavage from 191 patients with locally advanced rectal cancer scheduled for radical treatment. Mitochondrial DNA target sequences were amplified by polymerase chain reaction and base substitutions were detected by denaturant, cycling temperature capillary electrophoresis. Detection of intraperitoneal free cancer cells was correlated to survival. RESULTS: Of 191patients analyzed, 138 (72%) were identified with somatic mitochondrial point mutations in rectal cancer tumors. From this fraction, 45 patients (33%) had positive lavage fluid with corresponding somatic mtDNA point mutations in lavage representing circulating intraperitoneal free cancer cells. There was no significant survival difference between patients identified with or without somatic mitochondrial DNA point mutations in the corresponding lavage. CONCLUSION: Somatic mitochondrial DNA point mutations identified in primary rectal tumors enable detection of circulating intraperitoneal free cancer cells in lavage fluid. Intraperitoneal free cancer cells harvested from lavage immediately after surgery for rectal cancer does not represent an independent prognostic factor on survival.


Assuntos
Líquido Ascítico/patologia , Células Neoplásicas Circulantes , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Lavagem Peritoneal/métodos , Prognóstico , Estudos Prospectivos , Neoplasias Retais/patologia , População Branca
12.
BMC Clin Pathol ; 17: 6, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28405177

RESUMO

BACKGROUND: The growth of tumor cells is accompanied by mutations in nuclear and mitochondrial genomes creating marked genetic heterogeneity. Tumors also contain non-tumor cells of various origins. An observed somatic mitochondrial mutation would have occurred in a founding cell and spread through cell division. Micro-anatomical dissection of a tumor coupled with assays for mitochondrial point mutations permits new insights into this growth process. More generally, the ability to detect and trace, at a histological level, somatic mitochondrial mutations in human tissues and tumors, makes these mutations into markers for lineage tracing. METHOD: A tumor was first sampled by a large punch biopsy and scanned for any significant degree of heteroplasmy in a set of sequences containing known mutational hotspots of the mitochondrial genome. A heteroplasmic tumor was sliced at a 12 µm thickness and placed on membranes. Laser capture micro-dissection was used to take 25000 µm2 subsamples or spots. After DNA amplification, cycling temperature capillary electrophoresis (CTCE) was used on the laser captured samples to quantify mitochondrial mutant fractions. RESULTS: Of six testicular tumors studied, one, a Leydig tumor, was discovered to carry a detectable degree of heteroplasmy for two separate point mutations: a C → T mutation at bp 64 and a T → C mutation found at bp 152. From this tumor, 381 spots were sampled with laser capture micro-dissection. The ordered distribution of spots exhibited a wide range of fractions of the mutant sequences from 0 to 100% mutant copies. The two mutations co-distributed in the growing tumor indicating they were present on the same genome copies in the founding cell. CONCLUSION: Laser capture microdissection of sliced tumor samples coupled with CTCE-based point mutation assays provides an effective and practical means to obtain maps of mitochondrial mutational heteroplasmy within human tumors.

13.
J Cutan Pathol ; 43(7): 571-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27020606

RESUMO

BACKGROUND: Keratoacanthoma (KA) is a common keratinocytic skin neoplasm that typically develops rapidly and undergoes complete spontaneous regression. As the pro-apoptotic p53 protein may be involved in the lifecycle of KA, we studied the p53 status throughout the main stages of KA that include proliferation, maturation and regression in a large series of lesions. METHODS: One-hundred and twenty-four KAs were characterized with respect to age of the lesions both clinically and histopathologically, in addition to phenotypic characteristics such as cellular atypia, infiltration, inflammation and fibrosis. Tp53 mutations were detected by capillary electrophoresis, and p53 protein levels were assessed by immunohistochemistry. RESULTS: Tp53 mutations were detected in 49 cases (39.5%) and were associated with high p53 protein levels (p = 0.007) and histopathologic age of the lesions (p = 0.044). Significant association was also seen between high p53 protein levels and atypia (p = 0.036), whereas the association with infiltration showed borderline significance (p = 0.057). High p53 protein levels were significantly associated with gene mutations in transplanted, but not in non-transplanted patients. CONCLUSION: We show a high frequency of Tp53 mutations in KAs that is associated with increased p53 levels. The results indicate a role for the p53 protein in KA development.


Assuntos
Ceratoacantoma/patologia , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/biossíntese , Adulto , Idoso , Análise Mutacional de DNA , Eletroforese Capilar , Feminino , Humanos , Imuno-Histoquímica , Ceratoacantoma/genética , Ceratoacantoma/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética
14.
Proc Natl Acad Sci U S A ; 110(7): E593-601, 2013 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-23359713

RESUMO

The epigenetic regulator Bmi1 controls proliferation in many organs. Reexpression of cell cycle proteins such as cyclin-dependent kinases (CDKs) is a hallmark of neuronal apoptosis in neurodegenerative diseases. Here we address the potential role of Bmi1 as a key regulator of cell cycle proteins during neuronal apoptosis. We show that several cell cycle proteins are expressed in different models of retinal degeneration and required in the Rd1 photoreceptor death process. Deleting E2f1, a downstream target of CDKs, provided temporary protection in Rd1 mice. Most importantly, genetic ablation of Bmi1 provided extensive photoreceptor survival and improvement of retinal function in Rd1 mice, mediated by a decrease in cell cycle markers and regulators independent of p16(Ink4a) and p19(Arf). These data reveal that Bmi1 controls the cell cycle-related death process, highlighting this pathway as a promising therapeutic target for neuroprotection in retinal dystrophies.


Assuntos
Apoptose/fisiologia , Proteínas de Ciclo Celular/metabolismo , Epigênese Genética/fisiologia , Regulação da Expressão Gênica/fisiologia , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Degeneração Retiniana/metabolismo , Análise de Variância , Animais , Fator de Transcrição E2F1/metabolismo , Epigênese Genética/genética , Regulação da Expressão Gênica/genética , Técnicas Histológicas , Camundongos , Camundongos Knockout , Microscopia de Fluorescência , Complexo Repressor Polycomb 1/genética , Proteínas Proto-Oncogênicas/genética
15.
BMC Womens Health ; 15: 59, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26272803

RESUMO

BACKGROUND: Women with endometriosis often experience gastrointestinal symptoms. Gonadotropin-releasing hormone (GnRH) analogs are used to treat endometriosis; however, some patients develop gastrointestinal dysmotility following this treatment. The aims of the present study were to investigate gastrointestinal symptoms among patients with endometriosis and to examine whether symptoms were associated with menstruation, localization of endometriosis lesions, or treatment with either opioids or GnRH analogs, and if hormonal treatment affected the symptoms. METHODS: All patients with diagnosed endometriosis at the Department of Gynecology were invited to participate in the study. Gastrointestinal symptoms were registered using the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS); socioeconomic and medical histories were compiled using a clinical data survey. Data were compared to a control group from the general population. RESULTS: A total of 109 patients and 65 controls were investigated. Compared to controls, patients with endometriosis experienced significantly aggravated abdominal pain (P = 0.001), constipation (P = 0.009), bloating and flatulence (P = 0.000), defecation urgency (P = 0.010), and sensation of incomplete evacuation (P = 0.050), with impaired psychological well-being (P = 0.005) and greater intestinal symptom influence on their daily lives (P = 0.001). The symptoms were not associated with menstruation or localization of endometriosis lesions, except increased nausea and vomiting (P = 0.010) in patients with bowel-associated lesions. Half of the patients were able to differentiate between abdominal pain from endometriosis and from the gastrointestinal tract. Patients using opioids experienced more severe symptoms than patients not using opioids, and patients with current or previous use of GnRH analogs had more severe abdominal pain than the other patients (P = 0.024). Initiation of either combined oral contraceptives or progesterone for endometriosis had no effect on gastrointestinal symptoms when the patients were followed prospectively. CONCLUSIONS: The majority of endometriosis patients experience more severe gastrointestinal symptoms than controls. A poor association between symptoms and lesion localization was found, indicating existing comorbidity between endometriosis and irritable bowel syndrome (IBS). Treatment with opioids or GnRH analogs is associated with aggravated gastrointestinal symptoms.


Assuntos
Dor Abdominal/etiologia , Endometriose/complicações , Gastroenteropatias/etiologia , Dor Abdominal/diagnóstico , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Constipação Intestinal/etiologia , Feminino , Gastroenteropatias/diagnóstico , Humanos , Síndrome do Intestino Irritável/etiologia , Náusea/etiologia , Medição da Dor , Inquéritos e Questionários , Vômito/etiologia , Adulto Jovem
16.
Hered Cancer Clin Pract ; 13(1): 14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26052370

RESUMO

BACKGROUND: Common genetic variants have been shown to modify BRCA1 penetrance. The aim of this study was to validate these reports in a special cohort of Norwegian BRCA1 mutation carriers that were selected for their extreme age of onset of disease. METHODS: The ten variants rs13387042, rs3803662, rs8170, rs9397435, rs700518, rs10046, rs3834129, rs1045485, rs2363956 and rs16942 were selected to be tested on samples from our biobank. We selected female BRCA1 mutation carriers having had a diagnosis of breast or ovarian cancer below 40 years of age (young cancer group, N = 40), and mutation carriers having had neither breast nor ovarian cancer above 60 years of age (i.e., old no cancer group, N = 38). Relative risks and odd ratios of belonging to the young cancer versus old no cancer groups were calculated as a function of having or not having the SNPs in question. RESULTS: Five of the ten variants were found to be significantly associated with early onset cancer. Some of the variation between our results and those previously reported may be ascribed to stochastic effects in our limited number of patient studies, and/or genetic drift in linkage disequilibrium in the genetically isolated Norwegian population. This is in accordance with the understanding that the SNPs are markers in linkage disequilibrium with their respective disease-causing genetic variants, and that this may vary between different populations. CONCLUSIONS: The results confirmed associations previously reported, with the notion that the degree of association may differ between other populations, which must be considered when discussing the clinical use of the associations described.

17.
J Neurochem ; 127(6): 868-79, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23796581

RESUMO

Retinitis Pigmentosa involves a hereditary degeneration of photoreceptors by as yet unresolved mechanisms. The secretable protein α-Klotho has a function related to ageing processes, and α-Klotho-deficient mice have reduced lifespan and declining functions in several tissues. Here, we studied Klotho in connection with inherited photoreceptor degeneration. Increased nuclear immunostaining for α-Klotho protein was seen in degenerating photoreceptors in four different Retinitis Pigmentosa models (rd1, rd2 mice; P23H, S334ter rhodopsin mutant rats). Correspondingly, in rd1 retina α-Klotho mRNA expression was significantly up-regulated. Moreover, immunostaining for another Klotho family protein, ß-Klotho, also co-localized with degenerating rd1 photoreceptors. The rd1 retina displayed reduced levels of fibroblast growth factor 15, a member of the fibroblast growth factor subfamily for which Klotho acts as a co-receptor. Exogenous α-Klotho protein added to retinal explant cultures did not affect cell death in rd1 retinae, but caused a severe layer disordering in wild-type retinae. Our study suggests Klotho as a novel player in the retina, with a clear connection to photoreceptor cell death as well as with an influence on retinal organization.


Assuntos
Glucuronidase/metabolismo , Proteínas de Membrana/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Retinose Pigmentar/metabolismo , Animais , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Glucuronidase/farmacologia , Proteínas Klotho , Masculino , Camundongos , Camundongos Endogâmicos C3H , Células Fotorreceptoras de Vertebrados/patologia , Isoformas de Proteínas/metabolismo , Retina/efeitos dos fármacos , Retina/metabolismo , Retina/patologia , Retinose Pigmentar/patologia , Técnicas de Cultura de Tecidos , Regulação para Cima
18.
Paediatr Perinat Epidemiol ; 27(1): 72-80, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23215714

RESUMO

BACKGROUND: A previous caesarean delivery is no longer an indication per se for a subsequent, planned caesarean. We performed this study to identify women suitable for trial of labour after caesarean (TOLAC), investigating the association between the indication for the first caesarean and the risk of unplanned caesarean in the second pregnancy. METHODS: We identified women with their first two pregnancies registered in the Swedish Medical Birth Registry 1992-2007. The indications for caesarean in the first pregnancy were determined using a previously published hierarchical system. For each indication group, the rate of caesarean among women with a first caesarean (n = 59 643) and a TOLAC in the second pregnancy was compared with that of primiparae (parity 0) (n = 354 053). RESULTS: The TOLAC rate was 69.5%. Among women with TOLAC, the uterine rupture rate was 1.1%. The success rate of TOLAC varied substantially based on the indication for the first caesarean (range 51-83%). Multiple births, breech presentation, and placenta praevia in the first pregnancy were associated with marginally increased odds of unplanned caesarean in the second pregnancy when compared with primiparae (adjusted OR 1.27 [95% CI 1.10, 1.48], 1.42 [1.34, 1.51], and 1.65 [1.17, 2.31]; OR, odds ratio; CI, confidence interval). The indications based on complications during labour/delivery, macrosomia, and maternal diabetes, were associated with substantially increased OR: 3.87 [3.70, 4.06], 4.15 [3.74, 4.61], and 4.62 [3.79, 5.63], respectively. CONCLUSIONS: Considering the indications for caesarean in the first pregnancy before recommending a TOLAC or a planned caesarean in the second pregnancy may help to lower the rate of unplanned caesarean deliveries.


Assuntos
Cesárea/estatística & dados numéricos , Prova de Trabalho de Parto , Nascimento Vaginal Após Cesárea/estatística & dados numéricos , Adolescente , Adulto , Cesárea/psicologia , Recesariana/psicologia , Recesariana/estatística & dados numéricos , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Monitorização Fisiológica , Gravidez , Fatores de Risco , Suécia , Fatores de Tempo , Nascimento Vaginal Após Cesárea/psicologia , Adulto Jovem
19.
Ambio ; 42(4): 497-505, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23619807

RESUMO

Assessments of radiological impacts on humans and other biota from potential releases to the biosphere from a deep geologic repository for spent nuclear fuel are associated with several challenges. Releases, if any, will likely occur in a far future and to an environment that will have experienced substantial transformations. Such releases would occur over very long periods during which environmental conditions will vary continuously due to climate change and ecosystem succession. Assessments of radiological impacts must therefore be based on simulations using models that can describe the transport and accumulation of radionuclides for a large variety of environmental conditions. In this paper we describe such a model and show examples of its application in a safety assessment, taking into account results from sensitivity and uncertainty analyses of the model predictions.


Assuntos
Modelos Teóricos , Poluentes Radioativos/química , Radioisótopos/química , Incerteza
20.
ASN Neuro ; 15: 17590914231151534, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36799552

RESUMO

Retinitis pigmentosa (RP) is an inherited disorder that results in vision impairment but general and mutation-independent therapeutic strategies are not available. However, it is widely regarded that the cGMP system, including cGMP and its interactor cGMP-dependent protein kinase (PKG), acts as a crucial effector during retinal degeneration. We have previously identified a list of cGMP-PKG-dependent genes in the context of RP, and in this study, we further validated one of these, namely pyruvate kinase 2 (PKM2), and investigated the potential role of PKM2 for the photoreceptors' well-being during RP. With the aid of organotypic retinal explant cultures, we pharmacologically manipulated the PKM2 activities in two different RP mouse models (rd2 and rd10) via the addition of TEPP-46 (a PKM2 activator) and found that activation of PKM2 alleviates the progress of photoreceptor death in the rd10 mouse model. We also noted that the expression of both PKM2 and one of its targets, glucose transporter-1 (Glut1), showed alterations depending on the degeneration state. The observations provide supportive evidence that PKM2 may serve as a novel potential molecular target in RP.


Assuntos
Piruvato Quinase , Degeneração Retiniana , Retinose Pigmentar , Animais , Camundongos , Modelos Animais de Doenças , Metabolismo Energético , Camundongos Endogâmicos C57BL , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Retina/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo
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