Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 39
1.
Hepatology ; 2024 Apr 02.
Article En | MEDLINE | ID: mdl-38563629

BACKGROUND AND AIMS: Fibrosis is the common end point for all forms of chronic liver injury, and the progression of fibrosis leads to the development of end-stage liver disease. Activation of HSCs and their transdifferentiation into myofibroblasts results in the accumulation of extracellular matrix proteins that form the fibrotic scar. Long noncoding RNAs regulate the activity of HSCs and provide targets for fibrotic therapies. APPROACH AND RESULTS: We identified long noncoding RNA TILAM located near COL1A1 , expressed in HSCs, and induced with liver fibrosis in humans and mice. Loss-of-function studies in human HSCs and human liver organoids revealed that TILAM regulates the expression of COL1A1 and other extracellular matrix genes. To determine the role of TILAM in vivo, we annotated the mouse ortholog ( Tilam ), generated Tilam- deficient green fluorescent protein-reporter mice, and challenged these mice in 2 different models of liver fibrosis. Single-cell data and analysis of single-data and analysis of Tilam-deficient reporter mice revealed that Tilam is induced in murine HSCs with the development of fibrosis in vivo. Tilam -deficient reporter mice revealed that Tilam is induced in murine HSCs with the development of fibrosis in vivo. Furthermore, loss of Tilam expression attenuated the development of fibrosis in the setting of in vivo liver injury. Finally, we found that TILAM interacts with promyelocytic leukemia nuclear body scaffold protein to regulate a feedback loop by which TGF-ß2 reinforces TILAM expression and nuclear localization of promyelocytic leukemia nuclear body scaffold protein to promote the fibrotic activity of HSCs. CONCLUSIONS: TILAM is activated in HSCs with liver injury and interacts with promyelocytic leukemia nuclear body scaffold protein to drive the development of fibrosis. Depletion of TILAM may serve as a therapeutic approach to combat the development of end-stage liver disease.

2.
EMBO J ; 42(24): e113898, 2023 Dec 11.
Article En | MEDLINE | ID: mdl-37962490

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing cause of morbidity with limited treatment options. Thus, accurate in vitro systems to test new therapies are indispensable. While recently, human liver organoid models have emerged to assess steatotic liver disease, a systematic evaluation of their translational potential is still missing. Here, we evaluated human liver organoid models of MASLD, comparatively testing disease induction in three conditions: oleic acid, palmitic acid, and TGF-ß1. Through single-cell analyses, we find that all three models induce inflammatory signatures, but only TGF-ß1 promotes collagen production, fibrosis, and hepatic stellate cell expansion. In striking contrast, oleic acid ameliorates fibrotic signatures and reduces the hepatic stellate cell population. Linking data from each model to gene expression signatures associated with MASLD disease progression further demonstrates that palmitic acid and TGF-ß1 more robustly model inflammation and fibrosis. Our findings highlight the importance of stratifying MASLD organoid models by signatures of clinical disease progression, provide a single-cell reference to benchmark future organoid injury models, and allow us to study evolving steatohepatitis, fibrosis, and HSC susceptibility to injury in a dynamic, multi-lineage human in vitro system.


Fatty Liver , Liver Cirrhosis , Humans , Liver Cirrhosis/genetics , Liver Cirrhosis/metabolism , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism , Fatty Liver/genetics , Gene Expression Profiling , Disease Progression
3.
bioRxiv ; 2023 Jul 30.
Article En | MEDLINE | ID: mdl-37546982

Background & Aims: Fibrosis is the common endpoint for all forms of chronic liver injury, and progression of fibrosis leads to the development of end-stage liver disease. Activation of hepatic stellate cells (HSCs) and their transdifferentiation to myofibroblasts results in the accumulation of extracellular matrix (ECM) proteins that form the fibrotic scar. Long noncoding (lnc) RNAs regulate the activity of HSCs and may provide targets for fibrotic therapies. Methods: We identified lncRNA TILAM as expressed near COL1A1 in human HSCs and performed loss-of-function studies in human HSCs and liver organoids. Transcriptomic analyses of HSCs isolated from mice defined the murine ortholog of TILAM . We then generated Tilam -deficient GFP reporter mice and quantified fibrotic responses to carbon tetrachloride (CCl 4 ) and choline-deficient L-amino acid defined high fat diet (CDA-HFD). Co-precipitation studies, mass spectrometry, and gene expression analyses identified protein partners of TILAM . Results: TILAM is conserved between human and mouse HSCs and regulates expression of ECM proteins, including collagen. Tilam is selectively induced in HSCs during the development of fibrosis in vivo . In both male and female mice, loss of Tilam results in reduced fibrosis in the setting of CCl 4 and CDA-HFD injury models. TILAM interacts with promyelocytic leukemia protein (PML) to stabilize PML protein levels and promote the fibrotic activity of HSCs. Conclusion: TILAM is activated in HSCs and interacts with PML to drive the development of liver fibrosis. Depletion of TILAM may serve as a therapeutic approach to combat the development of end stage liver disease.

5.
Cell Host Microbe ; 30(10): 1370-1381.e5, 2022 10 12.
Article En | MEDLINE | ID: mdl-36130593

Inflammatory bowel disease (IBD) is driven by host genetics and environmental factors, including commensal microorganisms. Speckled Protein 140 (SP140) is an immune-restricted chromatin "reader" that is associated with Crohn's disease (CD), multiple sclerosis (MS), and chronic lymphocytic leukemia (CLL). However, the disease-causing mechanisms of SP140 remain undefined. Here, we identify an immune-intrinsic role for SP140 in regulating phagocytic defense responses to prevent the expansion of inflammatory bacteria. Mice harboring altered microbiota due to hematopoietic Sp140 deficiency exhibited severe colitis that was transmissible upon cohousing and ameliorated with antibiotics. Loss of SP140 results in blooms of Proteobacteria, including Helicobacter in Sp140-/- mice and Enterobacteriaceae in humans bearing the CD-associated SP140 loss-of-function variant. Phagocytes from patients with the SP140 loss-of-function variant and Sp140-/- mice exhibited altered antimicrobial defense programs required for control of pathobionts. Thus, mutations within this epigenetic reader may constitute a predisposing event in human diseases provoked by microbiota.


Crohn Disease , Inflammatory Bowel Diseases , Microbiota , Animals , Anti-Bacterial Agents , Antigens, Nuclear/genetics , Chromatin , Humans , Inflammatory Bowel Diseases/microbiology , Mice , Transcription Factors/genetics
6.
Elife ; 112022 05 26.
Article En | MEDLINE | ID: mdl-35617485

Chronic liver injury causes fibrosis, characterized by the formation of scar tissue resulting from excessive accumulation of extracellular matrix (ECM) proteins. Hepatic stellate cell (HSC) myofibroblasts are the primary cell type responsible for liver fibrosis, yet there are currently no therapies directed at inhibiting the activity of HSC myofibroblasts. To search for potential anti-fibrotic compounds, we performed a high-throughput compound screen in primary human HSC myofibroblasts and identified 19 small molecules that induce HSC inactivation, including the polyether ionophore nanchangmycin (NCMC). NCMC induces lipid re-accumulation while reducing collagen expression, deposition of collagen in the extracellular matrix, cell proliferation, and migration. We find that NCMC increases cytosolic Ca2+ and reduces the phosphorylated protein levels of FYN, PTK2 (FAK), MAPK1/3 (ERK2/1), HSPB1 (HSP27), and STAT5B. Further, depletion of each of these kinases suppress COL1A1 expression. These studies reveal a signaling network triggered by NCMC to inactivate HSC myofibroblasts and reduce expression of proteins that compose the fibrotic scar. Identification of the antifibrotic effects of NCMC and the elucidation of pathways by which NCMC inhibits fibrosis provide new tools and therapeutic targets that could potentially be utilized to combat the development and progression of liver fibrosis.


Cicatrix , Hepatic Stellate Cells , Cicatrix/pathology , Collagen/metabolism , Ethers , Extracellular Matrix Proteins/metabolism , Fibrosis , Focal Adhesion Kinase 1/metabolism , Hepatic Stellate Cells/metabolism , Humans , Liver Cirrhosis/drug therapy , Liver Cirrhosis/metabolism , Liver Cirrhosis/pathology , Mitogen-Activated Protein Kinase 1/metabolism , Spiro Compounds
7.
Gut ; 71(12): 2561-2573, 2022 12.
Article En | MEDLINE | ID: mdl-35365570

OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) can persist in the stage of simple hepatic steatosis or progress to steatohepatitis (NASH) with an increased risk for cirrhosis and cancer. We examined the mechanisms controlling the progression to severe NASH in order to develop future treatment strategies for this disease. DESIGN: NFATc1 activation and regulation was examined in livers from patients with NAFLD, cultured and primary hepatocytes and in transgenic mice with differential hepatocyte-specific expression of the transcription factor (Alb-cre, NFATc1c.a . and NFATc1Δ/Δ ). Animals were fed with high-fat western diet (WD) alone or in combination with tauroursodeoxycholic acid (TUDCA), a candidate drug for NAFLD treatment. NFATc1-dependent ER stress-responses, NLRP3 inflammasome activation and disease progression were assessed both in vitro and in vivo. RESULTS: NFATc1 expression was weak in healthy livers but strongly induced in advanced NAFLD stages, where it correlates with liver enzyme values as well as hepatic inflammation and fibrosis. Moreover, high-fat WD increased NFATc1 expression, nuclear localisation and activation to promote NAFLD progression, whereas hepatocyte-specific depletion of the transcription factor can prevent mice from disease acceleration. Mechanistically, NFATc1 drives liver cell damage and inflammation through ER stress sensing and activation of the PERK-CHOP unfolded protein response (UPR). Finally, NFATc1-induced disease progression towards NASH can be blocked by TUDCA administration. CONCLUSION: NFATc1 stimulates NAFLD progression through chronic ER stress sensing and subsequent activation of terminal UPR signalling in hepatocytes. Interfering with ER stress-responses, for example, by TUDCA, protects fatty livers from progression towards manifest NASH.


Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/metabolism , Liver/metabolism , Hepatocytes/metabolism , Transcription Factors/metabolism , Inflammation/metabolism , Mice, Transgenic , Disease Progression , Mice, Inbred C57BL , NFATC Transcription Factors/metabolism
8.
Sci Immunol ; 7(70): eabn6660, 2022 04 08.
Article En | MEDLINE | ID: mdl-35394816

Altered enteric microorganisms in concert with host genetics shape inflammatory bowel disease (IBD) phenotypes. However, insight is limited to bacteria and fungi. We found that eukaryotic viruses and bacteriophages (collectively, the virome), enriched from non-IBD, noninflamed human colon resections, actively elicited atypical anti-inflammatory innate immune programs. Conversely, ulcerative colitis or Crohn's disease colon resection viromes provoked inflammation, which was successfully dampened by non-IBD viromes. The IBD colon tissue virome was perturbed, including an increase in the enterovirus B species of eukaryotic picornaviruses, not previously detected in fecal virome studies. Mice humanized with non-IBD colon tissue viromes were protected from intestinal inflammation, whereas IBD virome mice exhibited exacerbated inflammation in a nucleic acid sensing-dependent fashion. Furthermore, there were detrimental consequences for IBD patient-derived intestinal epithelial cells bearing loss-of-function mutations within virus sensor MDA5 when exposed to viromes. Our results demonstrate that innate recognition of IBD or non-IBD human viromes autonomously influences intestinal homeostasis and disease phenotypes. Thus, perturbations in the intestinal virome, or an altered ability to sense the virome due to genetic variation, contribute to the induction of IBD. Harnessing the virome may offer therapeutic and biomarker potential.


Enterovirus , Gastrointestinal Microbiome , Inflammatory Bowel Diseases , Viruses , Animals , Humans , Immunomodulation , Inflammation , Mice , Phenotype
9.
Reprod Domest Anim ; 57(4): 402-417, 2022 Apr.
Article En | MEDLINE | ID: mdl-34971452

The present study aimed to use a comprehensive approach for evaluating 12 factors related to embryo quality (shape, size and transparency), donors (age, ET type, number of recovered embryos and day of uterine flushing), recipients (age), males (age and individual variations) and environment (season and year) which could affect the outcome of ET in terms of pregnancy (PR) and pregnancy losses in dromedary camels. During three breeding seasons, 116 donor females were mated repeatedly at 12- to 14-day intervals by fertile male camels (n = 33) without stimulation of the ovaries (WSPO). Superovulation (SPO ET) regimen was applied for each donor female twice or thrice per season. In the occasions of applying superovulation regimen, donor females having an ovulatory follicle were mated instead of GnRH administration and superovulation regimen was applied 4 days post-mating (MIX ET). The uteri of all donor females were flushed at Day 8 or 9 post-mating, and a total of 2,095 embryos were recovered and transferred individually to 924 recipient females. Pregnancy diagnoses were conducted at Day 10 after ET (Days 18-19 of gestation) by using progesterone assay and by transrectal ultrasonography (TRU) at Days 30 and 60 of gestation. By using logistic regression analysis, transparency of embryos and age of recipient females had significant effects on PR at Days 18-19 (p < .01), 30 (p < .01) and 60 (p < .01; p < .05, respectively) of gestation. The shape of embryos had significant effects on the PR at Days 30 (p < .05) and 60 (p < .01) of gestation. Type of ET and the breeding season (year) had significant (p < .05) effects on the PR at Day 30, while day of flushing had the same effect on PR at Day 60. Regarding the pregnancy losses, transparency and shape of the embryo, type of ET, breeding season had significant (p < .05) effect on the late embryonic mortalities (LEM) and shape and season of year had significant (p < .01 and p < .05, respectively) effect on LEM/early foetal mortalities (EFM). Regarding male individual factor, there was a tendency for a significant (p = .055) effect of male camels on the PR at Days 18-19 and rate of LEM. In conclusion, transferring a spherical, transparent or a large-sized embryo (>750 µm) into recipient females ageing between 8 and 11 y could greatly improve the PR from Days 18 to 60 of gestation. Also, embryo recovered from donor females with Mix ET type or embryos sired by certain male camel or at Day 8 post-mating of the donor could improve the 2-month PR. In addition, transferring a transparent or spherical-shaped embryo or embryos recovered from donor females with SPO or Mix ET could reduce the pregnancy losses during the first 2 months of pregnancy.


Abortion, Veterinary , Camelus , Animals , Camelus/physiology , Embryo Transfer/veterinary , Female , Male , Pregnancy , Retrospective Studies , Superovulation
10.
J Affect Disord ; 292: 526-533, 2021 09 01.
Article En | MEDLINE | ID: mdl-34147964

BACKGROUND: Associations between childhood trauma, personality, and Major Depressive Disorder (MDD) have been well established in studies conducted in high-income countries. However, there are limited studies on these associations in low and middle-income countries (LMICs), where MDD is highly prevalent. We assessed the relationships between childhood trauma, personality, and MDD in women in Karachi, Pakistan. METHOD: In this cross-sectional study of 455 female patients attending general medical outpatient clinics, a diagnosis of MDD was confirmed using the Structured Clinical Interview for DSM-IV (SCID); retrospective reports of childhood trauma were collected using the childhood trauma questionnaire (CTQ); and Big Five personality traits were assessed using the NEO Personality Inventory Revised (NEO PI-R). Other measures included the Life Events Questionnaire (LEQ) and the Multidimensional Scale of Perceived Social Support (MSPSS). Factors independently associated with MDD were determined using logistic regression analyses. RESULTS: Of the 455 women recruited between August 1, 2011 and July 31, 2013, 242 (53%) had a diagnosis of MDD. Women with MDD were significantly more likely to be separated, had more stressful life events and higher CTQ scores. Higher perceived social support, conscientiousness and extraversion were independently associated with significantly reduced odds of MDD. There were no significant associations between CTQ scores and any of the NEO PI-R subscales. LIMITATIONS: Ratings of childhood trauma were based on retrospective recall. CONCLUSION: MDD and a history of childhood trauma were highly prevalent in Pakistani women attending general medical clinics. Interventions to prevent childhood trauma and promote social support in women may improve public mental health in LMICs like Pakistan.


Depressive Disorder, Major , Developing Countries , Ambulatory Care Facilities , Cross-Sectional Studies , Depression , Depressive Disorder, Major/epidemiology , Female , Humans , Pakistan , Personality , Retrospective Studies , Social Support
11.
Nucleic Acids Res ; 48(D1): D204-D219, 2020 01 08.
Article En | MEDLINE | ID: mdl-31598718

We present the Small RNA Expression Atlas (SEAweb), a web application that allows for the interactive querying, visualization and analysis of known and novel small RNAs across 10 organisms. It contains sRNA and pathogen expression information for over 4200 published samples with standardized search terms and ontologies. In addition, SEAweb allows for the interactive visualization and re-analysis of 879 differential expression and 514 classification comparisons. SEAweb's user model enables sRNA researchers to compare and re-analyze user-specific and published datasets, highlighting common and distinct sRNA expression patterns. We provide evidence for SEAweb's fidelity by (i) generating a set of 591 tissue specific miRNAs across 29 tissues, (ii) finding known and novel bacterial and viral infections across diseases and (iii) determining a Parkinson's disease-specific blood biomarker signature using novel data. We believe that SEAweb's simple semantic search interface, the flexible interactive reports and the user model with rich analysis capabilities will enable researchers to better understand the potential function and diagnostic value of sRNAs or pathogens across tissues, diseases and organisms.


Databases, Nucleic Acid , RNA, Small Untranslated/metabolism , Animals , Bacterial Infections/microbiology , Cattle , Humans , Internet , Mice , Organ Specificity , Parkinson Disease/blood , RNA, Bacterial/metabolism , RNA, Viral/metabolism , Rats , Virus Diseases/virology
12.
PLoS Biol ; 17(8): e3000374, 2019 08.
Article En | MEDLINE | ID: mdl-31393866

A deep understanding of how regulation of the multiple levels of gene expression in mammalian tissues give rise to complex phenotypes has been impeded by cellular diversity. A handful of techniques were developed to tag-select nucleic acids of interest in specific cell types, thereby enabling their capture. We expanded this strategy by developing the Tagger knock-in mouse line bearing a quad-cistronic transgene combining enrichment tools for nuclei, nascent RNA, translating mRNA, and mature microRNA (miRNA). We demonstrate that Tagger can capture the desired nucleic acids, enabling multiple omics approaches to be applied to specific cell types in vivo using a single transgenic mouse line.


Gene Expression Profiling/methods , Nucleic Acids/isolation & purification , Whole Genome Sequencing/methods , Animals , Cloning, Molecular/methods , Gene Expression/genetics , Gene Expression Regulation/genetics , Gene Knock-In Techniques , Genomics/methods , Mice , Mice, Inbred C57BL , Mice, Transgenic/genetics , MicroRNAs/genetics , Proteomics/methods , RNA, Messenger/genetics , Transcriptome/genetics , Transgenes/genetics
13.
J Psychosom Res ; 120: 46-52, 2019 05.
Article En | MEDLINE | ID: mdl-30929707

OBJECTIVES: Evidence demonstrates the detrimental impact of depression in patients with congestive heart failure (CHF), however, large-scale prospective data from Low and Middle Income Countries (LMICs) is limited. We assessed the prevalence of depression in a large sample with CHF from Karachi, Pakistan, and the impact of depression on all-cause mortality, disability and health-related quality of life (QoL). METHODS: 1009 patients diagnosed with CHF were recruited from public hospitals in Karachi, Pakistan. Patients were screened for depression at baseline using the Beck Depression Inventory (BDI) and the diagnosis was confirmed using the Clinical Interview Schedule-Revised (CIS-R). Health-related QoL and disability were measured using the EuroQol (EQ-5D) and Brief Disability Questionnaire respectively at baseline and after a 6-month follow-up. RESULTS: A total of 670 (66%) patients were depressed at baseline and 821 participants completed 6-month follow up assessments (retention rate: 81%). At baseline, lower income (p < 0.001) and lower education level (p = 0.03) were associated with higher BDI scores. Higher BDI scores were associated with a history of depression (p < 0.001), higher NYHA class (p < 0.001), diabetes (p < 0.001), COPD (p = 0.007), renal disease (p < 0.001) and stroke (p = 0.02). 145 participants were deceased at 6-months. Regression analysis showed that at follow up, higher BDI scores in depressed participants were associated with higher all-cause mortality (OR 1.23 (95% CI: 1.11-1.36); p < 0.001). CONCLUSION: The rate of depression was high among Pakistani patients with CHF. Severity of depression correlated with increased mortality. Further research on controlled intervention trials in this population is warranted.


Depression/complications , Heart Failure/complications , Heart Failure/epidemiology , Aged , Cohort Studies , Female , Heart Failure/psychology , Humans , Male , Middle Aged , Pakistan/epidemiology , Prevalence , Prospective Studies , Psychiatric Status Rating Scales , Quality of Life , Surveys and Questionnaires
14.
BJPsych Open ; 5(1): e13, 2019 Jan.
Article En | MEDLINE | ID: mdl-30762508

BACKGROUND: A third of patients diagnosed with major depressive disorder (MDD) experience treatment-resistant depression (TRD). Relatively few pharmacological agents have established efficacy for TRD. Therefore, the evaluation of novel treatments for TRD is a pressing priority. Statins are pleiotropic agents and preclinical studies as well as preliminary clinical trials have suggested that these drugs may have antidepressant properties.AimsTo report on a protocol for a 12-week, randomised, double-blind, placebo-controlled trial of add-on treatment with simvastatin for patients meeting DSM-5 criteria for MDD who have failed to respond to at least two adequate trials with approved antidepressants. The trial has been registered with Clinicaltrials.gov in (ClinicalTrials.gov identifier: NCT03435744). METHOD: After screening and randomisation to the two parallel arms of the trial, 75 patients will receive simvastatin and 75 patients will receive placebo as adjuncts to treatment as usual. The primary outcome is change in Montgomery-Åsberg Depression Rating Scale scores from baseline to week 12 and secondary outcomes include changes in scores on the 24-item Hamilton Rating Scale for Depression, the Clinical Global Impression scale, the 7-item Generalized Anxiety Disorder scale and change in body mass index from baseline to week 12. Assessments will take place at screening, baseline, and weeks 2, 4, 8 and 12. Checklists for adverse effects will be undertaken at each visit. Simvastatin (20 mg) will be given once daily. Other secondary outcomes include C-reactive protein and plasma lipids measured at baseline and week 12. RESULTS: This trial will assess simvastatin's efficacy and tolerability as an add-on treatment option for patients with TRD and provide insights into its putative mechanisms of action. CONCLUSIONS: As the first trial investigating the use of simvastatin as an augmentation strategy in patients with TRD, if the results indicate that adjuvant simvastatin is efficacious in reducing depressive symptoms, it will deliver immediate clinical benefit.Declaration of interestI.B.C. and N.H. have given lectures and advice to Eli Lilly, Bristol Myers Squibb, Lundbeck, Astra Zeneca and Janssen pharmaceuticals for which they or their employing institution have been reimbursed. R.R. and M.M.H. have received educational grants and support for academic meetings from Pfizer, Roche, Novartis and Nabiqasim. A.H.Y. has been commissioned to provide lectures and advice to all major pharmaceutical companies with drugs used in affective and related disorders. A.H.Y. has undertaken investigator-initiated studies from Astra Zeneca, Eli Lilly, Lundbeck and Wyeth. None of the companies have a financial interest in this research.

15.
J Am Soc Nephrol ; 30(1): 63-78, 2019 01.
Article En | MEDLINE | ID: mdl-30518531

BACKGROUND: Nephron number is a major determinant of long-term renal function and cardiovascular risk. Observational studies suggest that maternal nutritional and metabolic factors during gestation contribute to the high variability of nephron endowment. However, the underlying molecular mechanisms have been unclear. METHODS: We used mouse models, including DNA methyltransferase (Dnmt1, Dnmt3a, and Dnmt3b) knockout mice, optical projection tomography, three-dimensional reconstructions of the nephrogenic niche, and transcriptome and DNA methylation analysis to characterize the role of DNA methylation for kidney development. RESULTS: We demonstrate that DNA hypomethylation is a key feature of nutritional kidney growth restriction in vitro and in vivo, and that DNA methyltransferases Dnmt1 and Dnmt3a are highly enriched in the nephrogenic zone of the developing kidneys. Deletion of Dnmt1 in nephron progenitor cells (in contrast to deletion of Dnmt3a or Dnm3b) mimics nutritional models of kidney growth restriction and results in a substantial reduction of nephron number as well as renal hypoplasia at birth. In Dnmt1-deficient mice, optical projection tomography and three-dimensional reconstructions uncovered a significant reduction of stem cell niches and progenitor cells. RNA sequencing analysis revealed that global DNA hypomethylation interferes in the progenitor cell regulatory network, leading to downregulation of genes crucial for initiation of nephrogenesis, Wt1 and its target Wnt4. Derepression of germline genes, protocadherins, Rhox genes, and endogenous retroviral elements resulted in the upregulation of IFN targets and inhibitors of cell cycle progression. CONCLUSIONS: These findings establish DNA methylation as a key regulatory event of prenatal renal programming, which possibly represents a fundamental link between maternal nutritional factors during gestation and reduced nephron number.


DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA (Cytosine-5-)-Methyltransferases/genetics , Kidney/embryology , Organogenesis/genetics , Stem Cells/cytology , Animals , Cell Differentiation/genetics , Cells, Cultured , DNA Methylation , Gene Expression Regulation, Developmental/genetics , Immunohistochemistry , Mice , Mice, Knockout , Nephrons/cytology , Nephrons/physiology , Rats , Rats, Wistar , Sensitivity and Specificity , Stem Cells/physiology , DNA Methyltransferase 3B
16.
Sci Rep ; 8(1): 16913, 2018 11 15.
Article En | MEDLINE | ID: mdl-30443017

The homeostasis of the proteome depends on the tight regulation of the mRNA and protein abundances, of the translation rates, and of the protein lifetimes. Results from several studies on prokaryotes or eukaryotic cell cultures have suggested that protein homeostasis is connected to, and perhaps regulated by, the protein and the codon sequences. However, this has been little investigated for mammals in vivo. Moreover, the link between the coding sequences and one critical parameter, the protein lifetime, has remained largely unexplored, both in vivo and in vitro. We tested this in the mouse brain, and found that the percentages of amino acids and codons in the sequences could predict all of the homeostasis parameters with a precision approaching experimental measurements. A key predictive element was the wobble nucleotide. G-/C-ending codons correlated with higher protein lifetimes, protein abundances, mRNA abundances and translation rates than A-/U-ending codons. Modifying the proportions of G-/C-ending codons could tune these parameters in cell cultures, in a proof-of-principle experiment. We suggest that the coding sequences are strongly linked to protein homeostasis in vivo, albeit it still remains to be determined whether this relation is causal in nature.


Brain/metabolism , Codon/genetics , Nerve Tissue Proteins/genetics , Amino Acid Sequence , Amino Acids/genetics , Animals , Base Composition/genetics , Base Sequence , Mice , Nerve Tissue Proteins/chemistry , Nucleotides/genetics , Proteostasis , RNA, Messenger/genetics , RNA, Messenger/metabolism
17.
Nat Commun ; 9(1): 4230, 2018 10 12.
Article En | MEDLINE | ID: mdl-30315172

The turnover of brain proteins is critical for organism survival, and its perturbations are linked to pathology. Nevertheless, protein lifetimes have been difficult to obtain in vivo. They are readily measured in vitro by feeding cells with isotopically labeled amino acids, followed by mass spectrometry analyses. In vivo proteins are generated from at least two sources: labeled amino acids from the diet, and non-labeled amino acids from the degradation of pre-existing proteins. This renders measurements difficult. Here we solved this problem rigorously with a workflow that combines mouse in vivo isotopic labeling, mass spectrometry, and mathematical modeling. We also established several independent approaches to test and validate the results. This enabled us to measure the accurate lifetimes of ~3500 brain proteins. The high precision of our data provided a large set of biologically significant observations, including pathway-, organelle-, organ-, or cell-specific effects, along with a comprehensive catalog of extremely long-lived proteins (ELLPs).


Brain/metabolism , Hippocampus/metabolism , beta-Galactosidase/metabolism , Animals , Computational Biology , Male , Mass Spectrometry , Mice , Models, Theoretical , beta-Galactosidase/genetics
18.
BMC Bioinformatics ; 19(1): 54, 2018 02 14.
Article En | MEDLINE | ID: mdl-29444641

BACKGROUND: Small RNA molecules play important roles in many biological processes and their dysregulation or dysfunction can cause disease. The current method of choice for genome-wide sRNA expression profiling is deep sequencing. RESULTS: Here we present Oasis 2, which is a new main release of the Oasis web application for the detection, differential expression, and classification of small RNAs in deep sequencing data. Compared to its predecessor Oasis, Oasis 2 features a novel and speed-optimized sRNA detection module that supports the identification of small RNAs in any organism with higher accuracy. Next to the improved detection of small RNAs in a target organism, the software now also recognizes potential cross-species miRNAs and viral and bacterial sRNAs in infected samples. In addition, novel miRNAs can now be queried and visualized interactively, providing essential information for over 700 high-quality miRNA predictions across 14 organisms. Robust biomarker signatures can now be obtained using the novel enhanced classification module. CONCLUSIONS: Oasis 2 enables biologists and medical researchers to rapidly analyze and query small RNA deep sequencing data with improved precision, recall, and speed, in an interactive and user-friendly environment. AVAILABILITY AND IMPLEMENTATION: Oasis 2 is implemented in Java, J2EE, mysql, Python, R, PHP and JavaScript. It is freely available at https://oasis.dzne.de.


RNA, Small Untranslated/genetics , Sequence Analysis, RNA/methods , Statistics as Topic/methods , Base Sequence , Gene Expression Profiling , High-Throughput Nucleotide Sequencing , MicroRNAs/genetics , Software
19.
Mol Syst Biol ; 13(12): 959, 2017 12 14.
Article En | MEDLINE | ID: mdl-29242366

Mutually exclusive splicing of exons is a mechanism of functional gene and protein diversification with pivotal roles in organismal development and diseases such as Timothy syndrome, cardiomyopathy and cancer in humans. In order to obtain a first genomewide estimate of the extent and biological role of mutually exclusive splicing in humans, we predicted and subsequently validated mutually exclusive exons (MXEs) using 515 publically available RNA-Seq datasets. Here, we provide evidence for the expression of over 855 MXEs, 42% of which represent novel exons, increasing the annotated human mutually exclusive exome more than fivefold. The data provide strong evidence for the existence of large and multi-cluster MXEs in higher vertebrates and offer new insights into MXE evolution. More than 82% of the MXE clusters are conserved in mammals, and five clusters have homologous clusters in Drosophila Finally, MXEs are significantly enriched in pathogenic mutations and their spatio-temporal expression might predict human disease pathology.


RNA Splicing/genetics , Animals , Cluster Analysis , Disease/genetics , Evolution, Molecular , Exons/genetics , Genetic Loci , Genome, Human , Humans , Mammals/genetics , Mutation/genetics , Protein Folding , RNA, Messenger/genetics , RNA, Messenger/metabolism
20.
J Psychopharmacol ; 31(9): 1166-1175, 2017 09.
Article En | MEDLINE | ID: mdl-28857658

BACKGROUND: Evidence suggests that anti-inflammatory medication may be effective in the treatment of depressive symptoms. In this study, we aimed to investigate whether minocycline added to treatment as usual (TAU) for 3 months in patients with treatment-resistant depression will lead to an improvement in depressive symptoms. METHODS: Multi-site, 12-week, double-blind, placebo-controlled, pilot trial of minocycline added to TAU for patients suffering from DSM-5 major depressive disorder, whose current episode has failed to respond to at least two antidepressants. The primary outcome measure was mean change in Hamilton Depression Rating Scale (HAMD-17) scores from baseline to week 12. Secondary measures were the Clinical Global Impression scale (CGI), Patient Health Questionnaire-9 (PHQ-9), the Generalised Anxiety Disorder scale (GAD-7) and EuroQoL (EQ-5D) quality-of-life questionnaire. Side-effect checklists were also used. Minocycline was started at 100 mg once daily (OD) and increased to 200 mg after 2 weeks. RESULTS: A total of 41 participants were randomised, with 21 in the minocycline group and 20 in the placebo group. A large decrease in HAMD scores was observed in the minocycline group compared to the placebo group (standardised effect size (ES) -1.21, p < 0.001). CGI scores in the minocycline group also showed a large improvement compared with placebo (odds ratio (OR): 17.6, p < 0.001). PHQ-9, GAD-7 and EQ-5D total showed more moderate improvements (ES ~ 0.4-0.5). CONCLUSION: The findings indicate that adjunctive minocycline leads to improvement in symptoms of treatment-resistant depression. However, our findings require replication in a larger sample. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02263872, registered October 2014.


Antidepressive Agents/therapeutic use , Depressive Disorder, Major/drug therapy , Depressive Disorder, Treatment-Resistant/drug therapy , Minocycline/therapeutic use , Adult , Anti-Inflammatory Agents/therapeutic use , Double-Blind Method , Female , Humans , Male , Middle Aged , Pilot Projects , Psychiatric Status Rating Scales , Surveys and Questionnaires , Treatment Outcome
...