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1.
Proc Natl Acad Sci U S A ; 113(5): 1244-9, 2016 Feb 02.
Article in English | MEDLINE | ID: mdl-26787873

ABSTRACT

Graves' disease is an autoimmune disorder that causes hyperthyroidism because of autoantibodies that bind to the thyroid-stimulating hormone receptor (TSHR) on the thyroid gland, triggering thyroid hormone release. The physiological control of thyroid hormone homeostasis by the feedback loops involving the hypothalamus-pituitary-thyroid axis is disrupted by these stimulating autoantibodies. To reset the endogenous thyrotrophic feedback control, we designed a synthetic mammalian gene circuit that maintains thyroid hormone homeostasis by monitoring thyroid hormone levels and coordinating the expression of a thyroid-stimulating hormone receptor antagonist (TSHAntag), which competitively inhibits the binding of thyroid-stimulating hormone or the human autoantibody to TSHR. This synthetic control device consists of a synthetic thyroid-sensing receptor (TSR), a yeast Gal4 protein/human thyroid receptor-α fusion, which reversibly triggers expression of the TSHAntag gene from TSR-dependent promoters. In hyperthyroid mice, this synthetic circuit sensed pathological thyroid hormone levels and restored the thyrotrophic feedback control of the hypothalamus-pituitary-thyroid axis to euthyroid hormone levels. Therapeutic plug and play gene circuits that restore physiological feedback control in metabolic disorders foster advanced gene- and cell-based therapies.


Subject(s)
Disease Models, Animal , Gene Regulatory Networks , Genes, Synthetic , Graves Disease/genetics , Pituitary Gland/physiopathology , Thyroid Gland/physiopathology , Animals , Cells, Cultured , Feedback , Graves Disease/physiopathology , Humans , Mice , Thyroid Hormones/blood
2.
Ther Umsch ; 75(4): 225-233, 2018 Nov.
Article in German | MEDLINE | ID: mdl-30468116

ABSTRACT

Porphyria - when to think about how to clarify and treat? Abstract. Porphyrias are a group of metabolic disorders that are mostly hereditary. They manifest either as abdominal colic or as skin changes at light-exposed areas. During the symptomatic phase the diagnosis of porphyria can be made by cost-effective screening tests. If the screening gives a positive result, further testing is required to determine the exact type of porphyria and to establish the best therapeutic option for the patient in a specialized porphyria center.


Subject(s)
Porphyrias , Humans , Skin
3.
J Hepatol ; 65(1): 84-94, 2016 07.
Article in English | MEDLINE | ID: mdl-27067456

ABSTRACT

BACKGROUND & AIMS: The liver performs a panoply of complex activities coordinating metabolic, immunologic and detoxification processes. Despite the liver's robustness and unique self-regeneration capacity, viral infection, autoimmune disorders, fatty liver disease, alcohol abuse and drug-induced hepatotoxicity contribute to the increasing prevalence of liver failure. Liver injuries impair the clearance of bile acids from the hepatic portal vein which leads to their spill over into the peripheral circulation where they activate the G-protein-coupled bile acid receptor TGR5 to initiate a variety of hepatoprotective processes. METHODS: By functionally linking activation of ectopically expressed TGR5 to an artificial promoter controlling transcription of the hepatocyte growth factor (HGF), we created a closed-loop synthetic signalling network that coordinated liver injury-associated serum bile acid levels to expression of HGF in a self-sufficient, reversible and dose-dependent manner. RESULTS: After implantation of genetically engineered human cells inside auto-vascularizing, immunoprotective and clinically validated alginate-poly-(L-lysine)-alginate beads into mice, the liver-protection device detected pathologic serum bile acid levels and produced therapeutic HGF levels that protected the animals from acute drug-induced liver failure. CONCLUSIONS: Genetically engineered cells containing theranostic gene circuits that dynamically interface with host metabolism may provide novel opportunities for preventive, acute and chronic healthcare. LAY SUMMARY: Liver diseases leading to organ failure may go unnoticed as they do not trigger any symptoms or significant discomfort. We have designed a synthetic gene circuit that senses excessive bile acid levels associated with liver injuries and automatically produces a therapeutic protein in response. When integrated into mammalian cells and implanted into mice, the circuit detects the onset of liver injuries and coordinates the production of a protein pharmaceutical which prevents liver damage.


Subject(s)
Liver/injuries , Animals , Bile Acids and Salts , Chemical and Drug Induced Liver Injury , Humans , Liver Diseases , Mice , Synthetic Biology
4.
Ther Umsch ; 72(6): 375-80, 2015 Jun.
Article in German | MEDLINE | ID: mdl-26098187

ABSTRACT

Endocrine hypertension offers a potentially curative therapy if the underlying cause is identified and treated accordingly. In contrast to the high prevalence of arterial hypertension especially in the elderly, the classical endocrine causes remain a rare entity. Among patients with arterial hypertension the prevalence of Cushing's syndrome or pheochromocytoma is less than 1%. Primary hyperaldosteronism is more frequent with a reported prevalence of up to 9%. In order to avoid unnecessary, costly and potentially harmful evaluations and therapies due to the limited sensitivity and specificity of the critical endocrine tests it is mandatory to limit the exploration for endocrine causes to preselected patients with high pretest probability for an endocrine disorder. Younger age at manifestation of arterial hypertension or drug resistant hypertension together with other clinical signs of an endocrine disorder should raise the suspicion and prompt the appropriate evaluation.


Subject(s)
Endocrine System Diseases/complications , Hypertension/etiology , Diagnosis, Differential , Endocrine System Diseases/diagnosis , Humans
5.
Am J Physiol Endocrinol Metab ; 304(1): E1-13, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23092914

ABSTRACT

Obesity-related insulin resistance is linked to a chronic state of systemic and adipose tissue-derived inflammation. Glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone also acting on adipocytes. We investigated whether GIP affects inflammation, lipolysis, and insulin resistance in human adipocytes. Human subcutaneous preadipocyte-derived adipocytes, differentiated in vitro, were treated with human GIP to analyze mRNA expression and protein secretion of cytokines, glycerol, and free fatty acid release and insulin-induced glucose uptake. GIP induced mRNA expression of IL-6, IL-1ß, and the IL-1 receptor antagonist IL-1Ra, whereas TNFα, IL-8, and monocyte chemotactic protein (MCP)-1 remained unchanged. Cytokine induction involved PKA and the NF-κB pathway as well as an autocrine IL-1 effect. Furthermore, GIP potentiated IL-6 and IL-1Ra secretion in the presence of LPS, IL-1ß, and TNFα. GIP induced lipolysis via activation of hormone-sensitive lipase and was linked to NF-κB activation. Finally, chronic GIP treatment impaired insulin-induced glucose uptake possibly due to the observed impaired translocation of glucose transporter GLUT4. In conclusion, GIP induces an inflammatory and prolipolytic response via the PKA -NF-κB-IL-1 pathway and impairs insulin sensitivity of glucose uptake in human adipocytes.


Subject(s)
Adipocytes/drug effects , Cytokines/genetics , Gastric Inhibitory Polypeptide/pharmacology , Insulin Resistance , Lipolysis/drug effects , Adipocytes/metabolism , Adult , Anti-Obesity Agents/pharmacology , Cyclic AMP-Dependent Protein Kinases/metabolism , Cytokines/metabolism , Gastric Inhibitory Polypeptide/physiology , Humans , Insulin Resistance/genetics , Insulin Resistance/physiology , Interleukin 1 Receptor Antagonist Protein/genetics , Interleukin 1 Receptor Antagonist Protein/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Interleukin-6/genetics , Interleukin-6/metabolism , Lactones/pharmacology , Lipolysis/genetics , Middle Aged , NF-kappa B/metabolism , Orlistat , Signal Transduction/drug effects , Signal Transduction/genetics , Up-Regulation/drug effects , Up-Regulation/genetics
6.
Metab Eng ; 18: 9-24, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23542141

ABSTRACT

Induced pluripotent stem cells (iPSC) have successfully been derived from somatic fibroblasts through transfection of synthetic modified mRNA encoding transcription factors. This technique obviates the use of recombinant DNA and viral vectors in cellular reprogramming. The present study derived iPSC from adipose-derived mesenchymal stem cells (of a 50-year-old female patient) by utilizing a similar technique, but with defined culture medium without feeder cells, during both reprogramming and propagation. Clonal selection was performed to yield 12 putative iPSC lines from individual colonies of nascent reprogrammed cells, starting from 150,000 cells. However, only seven lines maintained their undifferentiated state after 10 continuous serial passages. These seven lines were then subjected to a rigorous battery of analyses to confirm their identity as iPSC. These tests included immunostaining, flow cytometry, qRT-PCR, in vitro differentiation assay, and teratoma formation assay within SCID mice. Positive results were consistently observed in all analyses, thus verifying the cells as fully reprogrammed iPSC. While all 7 iPSC lines displayed normal karyogram up to passage 13, chromosomal anomalies occurred in 4 of 7 lines with extended in vitro culture beyond 24 serial passages. Only three lines retained normal karyotype of 46,XX. The remaining four lines displayed mosaicism of normal and abnormal karyotypes. Hence, this study successfully derived iPSC from abundant and easily accessible adipose tissues of a middle-aged patient; utilizing a mRNA-based integration-free technique under feeder-free conditions. This is a step forward in translating iPSC into personalized regenerative medicine within the clinic.


Subject(s)
Adipose Tissue/metabolism , Induced Pluripotent Stem Cells/metabolism , Mesenchymal Stem Cells/metabolism , RNA, Messenger/chemistry , Transfection , Adipose Tissue/cytology , Animals , Cell Differentiation/genetics , Cell Line , Female , Humans , Induced Pluripotent Stem Cells/cytology , Mesenchymal Stem Cells/cytology , Mice , Mice, Inbred NOD , Mice, SCID , Middle Aged , RNA, Messenger/genetics , RNA, Messenger/metabolism
7.
Nat Commun ; 14(1): 3151, 2023 05 31.
Article in English | MEDLINE | ID: mdl-37258547

ABSTRACT

Precision medicine requires smart, ultrasensitive, real-time profiling of bio-analytes using interconnected miniaturized devices to achieve individually optimized healthcare. Here, we report a versatile bioelectronic interface (VIBE) that senses signaling-cascade-guided receptor-ligand interactions via an electronic interface. We show that VIBE offers a low detection limit down to sub-nanomolar range characterised by an output current that decreases significantly, leading to precise profiling of these peptide hormones throughout the physiologically relevant concentration ranges. In a proof-of-concept application, we demonstrate that the VIBE platform differentiates insulin and GLP-1 levels in serum samples of wild-type mice from type-1 and type-2 diabetic mice. Evaluation of human serum samples shows that the bioelectronic device can differentiate between samples from different individuals and report differences in their metabolic states. As the target analyte can be changed simply by introducing engineered cells overexpressing the appropriate receptor, the VIBE interface has many potential applications for point-of-care diagnostics and personalized medicine via the internet of things.


Subject(s)
Biosensing Techniques , Diabetes Mellitus, Experimental , Humans , Animals , Mice , Electronics , Insulin , Signal Transduction
8.
Life (Basel) ; 13(4)2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37109595

ABSTRACT

In animal models, melanocyte-stimulating hormones (MSHs) protect the liver from various injuries. Erythropoietic protoporphyria (EPP), a metabolic disorder, leads to the accumulation of protoporphyrin (PPIX). In addition to the most prominent symptom of incapacitating phototoxic skin reactions, 20% of EPP patients exhibit disturbed liver functioning and 4% experience terminal liver failure caused by the hepatobiliary elimination of excess PPIX. Skin symptoms are mitigated through the application of the controlled-release implant afamelanotide, an α-MSH analog, every sixty days. Recently, we showed that liver function tests (LFTs) improved during afamelanotide treatment when compared to before treatment. The present study investigated whether this effect is dose-dependent, as the evidence of dose dependency would support a beneficial influence of afamelanotide. METHODS: In this retrospective observational study, we included 2933 liver-function tests, 1186 PPIX concentrations and 1659 afamelanotide implant applications in 70 EPP patients. We investigated whether the number of days since the preceding afamelanotide dose or the number of doses during the preceding 365 days had an effect on LFTs and PPIX levels. In addition, we assessed the effect of global radiation. RESULTS: Inter-patient differences exerted the most prominent effect on PPIX and LFTs. In addition, PPIX increased significantly with an increase in the number of days since the last afamelanotide implant (p < 0.0001). ALAT and bilirubin decreased significantly with an increasing number of afamelanotide doses in the preceding 365 days (p = 0.012, p = 0.0299, respectively). Global radiation only influenced PPIX (p = 0.0113). CONCLUSIONS: These findings suggest that afamelanotide ameliorates both PPIX concentrations and LFTs in EPP in a dose-dependent manner.

10.
Ther Umsch ; 74(8): 409, 2017.
Article in German | MEDLINE | ID: mdl-29461144
12.
Ther Umsch ; 68(6): 315-20, 2011 Jun.
Article in German | MEDLINE | ID: mdl-21656490

ABSTRACT

Hypothyroidism is one of the most frequent endocrine disorders affecting 4.6% of the adult population. 90% of the cases represent subclinical hypothyroidism, defined by increased serum TSH but normal free thyroxine (fT4) values. General screening for hypothyroidism is not recommended because of lack of benefits for the patients. Search for hypothyroidism should therefore focus on patients with symptoms and signs and/or those presenting risk factors for development of hypothyroidism (e.g., autoimmune disorders, thyroid injury, post partum state). Because of the lack of specificity of sings and symptoms of this frequent disorder the diagnosis is based on measurement of TSH or TSH and fT4 in case of conditions that may affect TSH values such as non-thyroidal illness, or medications. Whereas primary hypothyroidism is due to lack of function of the thyroid itself and easy recognized by increased serum TSH, mild forms of secondary hypothyroidism may be difficult to detect because of the lack of function of the pituitary and thus absence of the best indicator of thyroid function. Here measurement of fT4 and a clinical assessment are the cornerstones for diagnosis of secondary hypothyroidism and monitoring of its treatment. In case of subclinical hypothyroidism defined as increased TSH but fT4 still within the normal laboratory range a TSH value above 10 mU/l is regarded as indication for treatment. For values between 4 and 10 mU/l an individualized pragmatic treatment approach based on the presence of clinical sings of hypothyroidism may be justified. Some patients however should be treated regardless of their clinical symptoms including women in childbearing age who want to become pregnant, patients with goitre, and patients with history of Graves disease. Treatment of hypothyroidism is best done with thyroxine (T4) alone; combination therapy of thyroxine with the active compound T3 does not have any advantage. The required L-T4 dose for optimal substitution (TSH between 0.5 and 2.5 mU/l) is in the range of 1.6 µg/kg body weight per day. In young subjects the starting dose should be close to the required dose i.e., 75 to 100 µg, elder patients and those with ischemic heart disease should start with lower doses (25-50 µg). Pregnant women under L-T4 substitution should increase the dose by 25% as soon as pregnancy is diagnosed.


Subject(s)
Hyperthyroidism/diagnosis , Hyperthyroidism/drug therapy , Thyroid Hormones/blood , Thyroid Hormones/therapeutic use , Adult , Biomarkers/blood , Female , Humans , Hyperthyroidism/blood , Pregnancy
13.
Ther Adv Rare Dis ; 2: 26330040211065453, 2021.
Article in English | MEDLINE | ID: mdl-37181106

ABSTRACT

Erythropoietic protoporphyria (EPP) is an ultra-rare inherited disorder with overproduction of protoporphyrin in maturating erythroblasts. This excess protoporphyrin leads to incapacitating phototoxic burns in sunlight exposed skin. Its biliary elimination causes cholestatic liver injury in 20% and terminal liver failure in 4% of EPP patients. Thereby, the risk of liver injury increases with increasing erythrocyte protoporphyrin concentrations. Afamelanotide, an α-melanocyte-stimulating hormone (MSH) analog inducing skin pigmentation, was shown to improve sunlight tolerance in EPP. Beyond this well-known effect on pigmentation, the MSHs have liver-protective effects and improve survival of maturating erythroblasts, effects described in animal or in vitro models to date only. We investigated whether afamelanotide treatment in EPP has effects on erythropoiesis, protoporphyrin concentrations, and liver injury by analyzing retrospectively our long-term safety data. Methods: From the 47 Swiss EPP-patients treated at our center since 2006, we included those 38 patients in the current analysis who received at least one afamelanotide dose between 2016 and 2018 and underwent regular laboratory testing before and during the treatment. We compared the means of pretreatment measurements with those during the treatment. Results: Protoporphyrin concentrations dropped from 21.39 ± 11.12 (mean ± SD) before afamelanotide to 16.83 ± 8.24 µmol/L (p < .0001) during treatment. Aspartate aminotransferase decreased from 26.67 ± 13.16 to 22.9 ± 7.76 IU/L (p = .0146). For both entities, patients with higher values showed a more progressive decrease, indicating a risk reduction of EPP-related liver disease. The pre-existing hypochromia and broad mean red-cell distribution width were further augmented under afamelanotide. This was more likely due to an influence of afamelanotide on maturating erythroblasts than due to an exacerbated iron deficiency, as mean zinc-protoporphyrin decreased significantly and ferritin remained unchanged. No serious afamelanotide-related adverse events were observed for a total of 240 treatment years. Conclusion: Our findings point to a protective effect of afamelanotide on erythroblast maturation and protoporphyrin-induced liver injury. Plain Language summary: Afamelanotide, a skin tanning hormone, may protect patients with erythropoietic protoporphyria not only from skin burns, but also from liver injury associated with the disease. Patients with erythropoietic protoporphyria (EPP), an inherited metabolic disease, suffer from light-induced skin burns and liver injury elicited by the accumulated light sensitizer protoporphyrin. The excess protoporphyrin is produced in red cell precursors in the bone marrow, and it is eliminated from the body via the liver and bile. A high protoporphyrin excretion burden damages the liver cells, the risk for this increases with higher protoporphyrin concentrations. About 20% of EPP patients show some sign of liver injury and 4% develop life-threatening liver dysfunction.Afamelanotide, closely related to natural α-melanocyte stimulating hormone (MSH), induces skin tanning. This effect protects EPP patients from light-induced skin burns as shown in previous studies. We have treated Swiss EPP patients with afamelanotide since 2006, and we regularly perform safety tests of this treatment.Recent in vitro and animal studies demonstrated α-MSH effects other than skin tanning, including an improved synthesis of red blood cell precursors in the bone-marrow and protection of the liver from experimentally induced damage. Until now, it is unknown whether afamelanotide has similar effects in the human organism.To study this question, we analyzed retrospectively the safety laboratory data of 38 Swiss patients, who received at least one dose of afamelanotide from 2016 to 2019. We found that both, the average protoporphyrin concentrations and aspartate aminotransferase, a test for liver function, improved during afamelanotide treatment as compared to before.We concluded that afamelanotide applied to EPP patients to protect them from light-induced skin burns also may reduce their risk of liver injury.

14.
Am J Respir Crit Care Med ; 179(10): 939-49, 2009 May 15.
Article in English | MEDLINE | ID: mdl-19234103

ABSTRACT

RATIONALE: The mouse model of bleomycin-induced lung injury offers an approach to study idiopathic pulmonary fibrosis, a progressive interstitial lung disease with poor prognosis. Progenitor cell-based treatment strategies might combine antiinflammatory effects and the capacity for tissue repair. OBJECTIVES: To expand progenitor cells with reparative and regenerative capacities and to evaluate their protective effects on pulmonary fibrosis in vivo. METHODS: Prominin-1/CD133(+) epithelial progenitor cells (PEPs) were expanded from adult mouse lungs after digestion and culture of distal airways. Lung fibrosis was induced in C57Bl/6 mice by instillation of bleomycin. Two hours later, animals were transplanted with PEPs. Inflammation and fibrosis were assessed by immunohistochemistry, bronchoalveolar lavage fluid differentials, and real-time polymerase chain reaction. MEASUREMENTS AND MAIN RESULTS: PEPs expanded from mouse lungs were of bone marrow origin, coexpressed stem and hematopoietic cell markers, and differentiated in vitro into alveolar type II surfactant protein-C(+) epithelial cells. In bleomycin-challenged mice, intratracheally injected PEPs engrafted into the lungs and differentiated into type II pneumocytes. Furthermore, PEPs suppressed proinflammatory and profibrotic gene expression, prevented the recruitment of inflammatory cells, and protected bleomycin-challenged mice from pulmonary fibrosis. Mechanistically, the protective effect depended on upregulation of inducible nitric oxide synthase in PEPs and nitric oxide-mediated suppression of alveolar macrophage proliferation. Accordingly, PEPs from iNOS(-/-) but not iNOS(+/+) mice failed to protect from bleomycin-induced lung injury. CONCLUSIONS: The combined antiinflammatory and regenerative capacity of bone marrow-derived pulmonary epithelial progenitors offers a promising approach for development of cell-based therapeutic strategies against pulmonary fibrosis.


Subject(s)
Antigens, CD/biosynthesis , Glycoproteins/biosynthesis , Idiopathic Pulmonary Fibrosis/therapy , Stem Cell Transplantation/methods , AC133 Antigen , Animals , Bleomycin/administration & dosage , Bronchoalveolar Lavage Fluid/chemistry , Cell Differentiation/immunology , Disease Models, Animal , Epithelial Cells/cytology , Epithelial Cells/immunology , Idiopathic Pulmonary Fibrosis/chemically induced , Idiopathic Pulmonary Fibrosis/immunology , Idiopathic Pulmonary Fibrosis/metabolism , Macrophages, Alveolar/cytology , Macrophages, Alveolar/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nitric Oxide/biosynthesis , Nitric Oxide/immunology , Nitric Oxide Synthase Type II/deficiency , Nitric Oxide Synthase Type II/metabolism , Peptides , Pulmonary Alveoli/cytology , Pulmonary Alveoli/immunology , Regeneration , Respiratory Mucosa/cytology , Respiratory Mucosa/immunology , Reverse Transcriptase Polymerase Chain Reaction , Stem Cells/cytology , Stem Cells/immunology
15.
Acta Ophthalmol ; 98(3): e292-e300, 2020 May.
Article in English | MEDLINE | ID: mdl-31654495

ABSTRACT

PURPOSE: To evaluate early changes in retinal layers using optical coherence tomography (OCT) in patients with long-standing type 1 diabetes (DM1) receiving intensified insulin therapy. METHODS: In a cross-sectional case-control study 150 patients with DM1 and 150 age- and sex-matched healthy control participants underwent OCT imaging. Scans of both eyes were analysed for different layers (NFL, GCL (+IPL), INL, outer layer complex (OLC, including OPL, ONL and ELM) and photoreceptors (PR)) in all subfields of an ETDRS grid. All analyses were performed semi-automatically using custom software by certified graders of the Vienna Reading Center. ANOVA models were used to compare the mean thickness of the layers between patients and controls. RESULTS: Six hundred eyes with 512 datapoints in 49 b-scans in each OCT were analysed. Mean thickness in patients/controls was 31.35 µm/30.65 µm (NFL, p = 0.0347), 76.7 µm/73.15 µm (GCL, p ≤ 0.0001), 36.29 µm/37.13 µm (INL, p = 0.0116), 114.34 µm/112.02 µm (OLC, p < 0.0001) and 44.71 µm/44.69 µm (PR, p = 0.9401). When evaluating the ETDRS subfields separately for clinically meaningful hypotheses, a significant swelling of the GCL in patients could be found uniformly and a central swelling for the OLC, whereas the distribution of NFL and INL thickening suggests that their statistical significance was not clinically relevant. CONCLUSION: These preliminary results demonstrate that preclinical retinal changes in patients with long-standing DM1 can be found by retinal layer evaluation. However, the changes are layer-specific, with significant thickening of the GCL and less so of the OLC suggesting a role as an early sign for diffuse swelling and the evolution of DME even in well-controlled diabetes.


Subject(s)
Diabetes Mellitus, Type 1/complications , Diabetic Retinopathy/pathology , Retinal Ganglion Cells/pathology , Adult , Analysis of Variance , Case-Control Studies , Cross-Sectional Studies , Diabetes Mellitus, Type 1/physiopathology , Diabetic Retinopathy/diagnostic imaging , Female , Humans , Male , Middle Aged , Tomography, Optical Coherence
16.
Cardiovasc Res ; 80(2): 236-45, 2008 Nov 01.
Article in English | MEDLINE | ID: mdl-18621802

ABSTRACT

AIMS: Experimental autoimmune myocarditis (EAM) is a CD4(+) T cell-mediated mouse model of inflammatory heart disease. Tissue-resident bone marrow-derived cells adopt different cellular phenotypes depending on the local milieu. We expanded a specific population of bone marrow-derived prominin-1-expressing progenitor cells (PPC) from healthy heart tissue, analysed their plasticity, and evaluated their capacity to protect mice from EAM and heart failure. METHODS AND RESULTS: PPC were expanded from healthy mouse hearts. Analysis of CD45.1/CD45.2 chimera mice confirmed bone marrow origin of PPC. Depending on in vitro culture conditions, PPC differentiated into macrophages, dendritic cells, or cardiomyocyte-like cells. In vivo, PPC acquired a cardiac phenotype after direct injection into healthy hearts. Intravenous injection of PPC into myosin alpha heavy chain/complete Freund's adjuvant (MyHC-alpha/CFA)-immunized BALB/c mice resulted in heart-specific homing and differentiation into the macrophage phenotype. Histology revealed reduced severity scores for PPC-treated mice compared with control animals [treated with phosphate-buffered saline (PBS) or crude bone marrow at day 21 after MyHC-alpha/CFA immunization]. Echocardiography showed preserved fractional shortening and velocity of circumferential shortening in PPC but not PBS-treated MyHC-alpha/CFA-immunized mice. In vitro and in vivo data suggested that interferon-gamma signalling on PPC was critical for nitric oxide-mediated suppression of heart-specific CD4(+) T cells. Accordingly, PPC from interferon-gamma receptor-deficient mice failed to protect MyHC-alpha/CFA-immunized mice from EAM. CONCLUSION: Prominin-1-expressing, heart-resident, bone marrow-derived cells combine high plasticity, T cell-suppressing capacity, and anti-inflammatory in vivo effects.


Subject(s)
Antigens, CD/metabolism , Autoimmune Diseases/prevention & control , Glycoproteins/metabolism , Myocarditis/prevention & control , Myocardium/immunology , Peptides/metabolism , Stem Cell Transplantation , Stem Cells/immunology , AC133 Antigen , Animals , Autoimmune Diseases/immunology , Autoimmune Diseases/pathology , Autoimmune Diseases/physiopathology , CD4-Positive T-Lymphocytes/immunology , Cell Differentiation , Cell Lineage , Cell Movement , Cell Proliferation , Cells, Cultured , Disease Models, Animal , Freund's Adjuvant , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Myocardial Contraction , Myocarditis/immunology , Myocarditis/pathology , Myocarditis/physiopathology , Myocardium/pathology , Myosin Heavy Chains , Phenotype , Receptors, Interferon/deficiency , Receptors, Interferon/genetics , Interferon gamma Receptor
17.
Diabetes Care ; 42(7): 1340-1343, 2019 07.
Article in English | MEDLINE | ID: mdl-31221699

ABSTRACT

OBJECTIVE: Hypoglycemic events during driving are life-threatening complications in people with type 1 diabetes (T1D). While preliminary studies showed increased glucose demand in driving simulations, we investigated interstitial fluid (ISF) glucose when driving under real-life circumstances. RESEARCH DESIGN AND METHODS: We measured ISF glucose in 10 participants with stable T1D during a 2-h driving course using a continuous glucose monitoring system. RESULTS: Our data show a driving-associated rise of ISF glucose. Initially increasing glucose was followed by decreasing values. Under control conditions at the same time of the day without driving, no specific glucose changes were observed. CONCLUSIONS: Real-life driving may have caused an initial glucose increase followed by decreasing glucose values in this cohort with well-controlled T1D. These findings may be limited to the selected study population.


Subject(s)
Automobile Driving , Diabetes Mellitus, Type 1/metabolism , Extracellular Fluid/chemistry , Glucose/analysis , Adult , Biological Variation, Individual , Blood Glucose/analysis , Blood Glucose/metabolism , Blood Glucose Self-Monitoring/instrumentation , Blood Glucose Self-Monitoring/methods , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/drug therapy , Equipment and Supplies , Female , Glucose/metabolism , Humans , Insulin/therapeutic use , Male , Middle Aged
18.
Diabetes Res Clin Pract ; 148: 234-239, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30684505

ABSTRACT

AIM: Prevalence of retinopathy (DR) in patients with type 1 diabetes treated with education-based intensified insulin therapy (EBIIT) and its association with parameters of glucose control. METHODS: 151 patients with mean diabetes duration of 14.3 years [SD ±â€¯5.8]) were analyzed. Eyes were examined using standardized 7 field ETDRS (Early Treatment Diabetic Retinopathy Study) settings and images analyzed by a professional external reading center. The glucose exposure over time was defined as HbA1c years, i.e. the sum of the differences between annual mean HbA1c (in %) minus the ideal HbA1c of 6.0% (42 mmol/mol) for each diabetes year (e.g. HbA1c of 8% (64 mmol/mol) over 6 years gives an excess HbA1c of 2.0% (22 for mmol/mol) for 6 years, resulting in 12 HbA1c years (or 131 for mmol/mol)). RESULTS: The median (interquartile range) of individual mean HbA1c was 7.3% (6.8-7.8) [56 mmol/mol (51-62)]. and the median HbA1c years was 16.8 (9.1-29.1) [183 mmol/mol (99-319)]. No evidence for DR was found in 59 patients (39%), stage 1 DR in 43 (28.5%), stage 2 in 41 (27.2%), stage 3 in 7 (4.6%) and proliferative DR stage 4 in 1 patient. The best correlation between severity of DR and diabetes control measures was found for HbA1c years (Pearson r = 0.41, p < 0.001). CONCLUSIONS: In type 1 diabetes EBIIT is associated with good diabetes control and a low prevalence of DR. The cumulative glucose exposure over time given as HbA1c years is the best predictor for development of DR. ClinicalTrials.gov Identifier: NCT02307110.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 1/therapy , Diabetic Retinopathy/epidemiology , Insulin/administration & dosage , Patient Education as Topic/methods , Adult , Blood Glucose Self-Monitoring/methods , Combined Modality Therapy , Cross-Sectional Studies , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/complications , Diabetic Retinopathy/blood , Diabetic Retinopathy/prevention & control , Dose-Response Relationship, Drug , Female , Glycated Hemoglobin/analysis , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged , Prevalence , Young Adult
20.
Swiss Med Wkly ; 137 Suppl 155: 60S-67S, 2007 Mar 02.
Article in English | MEDLINE | ID: mdl-17874504

ABSTRACT

Replacement of insulin-producing cells represents an almost ideal treatment for patients with diabetes mellitus type 1. Transplantation of pancreatic islets of Langerhans--although successful in experienced centres--is limited by the lack of donor organs. Generation of insulin-producing cells from stem cells represents an attractive alternative. Stem cells with the potential to differentiate into insulin-producing cells include embryonic stem cells (ESC) as well as adult stem cells from various tissues including the pancreas, liver, central nervous system, bone marrow and adipose tissue. The use of human ESC is hampered by ethical concerns and the inability to create patient specific ESC with therapeutic cloning. Among adult stem cells mesenchymal stem cells appear to have a particular developmental plasticity ex vivo that include their ability to adopt a pancreatic endocrine phenotype. The present review summarises the current knowledge on the development of insulin-producing cells from stem cells with special emphasis on human mesenchymal stem cells isolated from the pancreas and adipose tissue.

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