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1.
Lancet ; 402(10403): 720-730, 2023 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-37364590

RESUMEN

BACKGROUND: Combining the GLP-1 receptor agonist semaglutide with the long-acting amylin analogue cagrilintide has weight-loss benefits; the impact on glycated haemoglobin (HbA1c) is unknown. This trial assessed the efficacy and safety of co-administered semaglutide with cagrilintide (CagriSema) in participants with type 2 diabetes. METHODS: This 32-week, multicentre, double-blind, phase 2 trial was conducted across 17 sites in the USA. Adults with type 2 diabetes and a BMI of 27 kg/m2 or higher on metformin with or without an SGLT2 inhibitor were randomly assigned (1:1:1) to once-weekly subcutaneous CagriSema, semaglutide, or cagrilintide (all escalated to 2·4 mg). Randomisation was done centrally using an interactive web response system and was stratified according to use of SGLT2 inhibitor treatment (yes vs no). The trial participants, investigators, and trial sponsor staff were masked to treatment assignment throughout the trial. The primary endpoint was change from baseline in HbA1c; secondary endpoints were bodyweight, fasting plasma glucose, continuous glucose monitoring (CGM) parameters, and safety. Efficacy analyses were performed in all participants who had undergone randomisation, and safety analyses in all participants who had undergone randomisation and received at least one dose of the trial medication. This trial is registered on ClinicalTrials.gov (NCT04982575) and is complete. FINDINGS: Between Aug 2 and Oct 18, 2021, 92 participants were randomly assigned to CagriSema (n=31), semaglutide (n=31), or cagrilintide (n=30). 59 (64%) participants were male; the mean age of participants was 58 years (SD 9). The mean change in HbA1c from baseline to week 32 (CagriSema: -2·2 percentage points [SE 0·15]; semaglutide: -1·8 percentage points [0·16]; cagrilintide: -0·9 percentage points [0·15]) was greater with CagriSema versus cagrilintide (estimated treatment difference -1·3 percentage points [95% CI -1·7 to -0·8]; p<0·0001), but not versus semaglutide (-0·4 percentage points [-0·8 to 0·0]; p=0·075). The mean change in bodyweight from baseline to week 32 (CagriSema: -15·6% [SE 1·26]; semaglutide: -5·1% [1·26]; cagrilintide: -8·1% [1·23]) was greater with CagriSema versus both semaglutide (p<0·0001) and cagrilintide (p<0·0001). The mean change in fasting plasma glucose from baseline to week 32 (CagriSema: -3·3 mmol/L [SE 0·3]; semaglutide: -2·5 mmol/L [0·4]; cagrilintide: -1·7 mmol/L [0·3]) was greater with CagriSema versus cagrilintide (p=0·0010) but not versus semaglutide (p=0·10). Time in range (3·9-10·0 mmol/L) was 45·9%, 32·6%, and 56·9% at baseline and 88·9%, 76·2%, and 71·7% at week 32 with CagriSema, semaglutide, and cagrilintide, respectively. Adverse events were reported by 21 (68%) participants in the CagriSema group, 22 (71%) in the semaglutide group, and 24 (80%) in the cagrilintide group. Mild or moderate gastrointestinal adverse events were most common; no level 2 or 3 hypoglycaemia was reported. No fatal adverse events were reported. INTERPRETATION: In people with type 2 diabetes, treatment with CagriSema resulted in clinically relevant improvements in glycaemic control (including CGM parameters). The mean change in HbA1c with CagriSema was greater versus cagrilintide, but not versus semaglutide. Treatment with CagriSema resulted in significantly greater weight loss versus semaglutide and cagrilintide and was well tolerated. These data support further investigation of CagriSema in this population in longer and larger phase 3 studies. FUNDING: Novo Nordisk.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Adulto , Masculino , Humanos , Persona de Mediana Edad , Femenino , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Polipéptido Amiloide de los Islotes Pancreáticos/uso terapéutico , Hipoglucemiantes/efectos adversos , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Glucemia , Automonitorización de la Glucosa Sanguínea , Resultado del Tratamiento , Péptidos Similares al Glucagón , Método Doble Ciego
2.
Int J Mol Sci ; 24(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37445727

RESUMEN

Podocytes are highly specialized cells that play a pivotal role in the blood filtration process in the glomeruli of the kidney, and their dysfunction leads to renal diseases. For this reason, the study and application of this cell type is of great importance in the field of regenerative medicine. Hypertension is mainly regulated by the renin-angiotensin-aldosterone system (RAAS), with its main mediator being angiotensin II (ANG II). Elevated ANG II levels lead to a pro-fibrotic, inflammatory, and hypertrophic milieu that induces apoptosis in podocytes. The activation of RAAS is critical for the pathogenesis of podocyte injury; as such, to prevent podocyte damage, patients with hypertension are administered drugs that modulate RAAS signaling. A prime example is the orally active, non-peptide, selective angiotensin-II-type I receptor (AGTR1) blocker losartan. Here, we demonstrate that SIX2-positive urine-derived renal progenitor cells (UdRPCs) and their immortalized counterpart (UM51-hTERT) can be directly differentiated into mature podocytes. These podocytes show activation of RAAS after stimulation with ANG II, resulting in ANG II-dependent upregulation of the expression of the angiotensin-II-type I receptor, AGTR1, and the downregulated expression of the angiotensin-II-type II receptor 2 (AGTR2). The stimulation of podocytes with losartan counteracts ANG II-dependent changes, resulting in a dependent favoring of the specific receptor from AGTR1 to AGTR2. Transcriptome analysis revealed 94 losartan-induced genes associated with diverse biological processes and pathways such as vascular smooth muscle contraction, the oxytocin signaling pathway, renin secretion, and ECM-receptor interaction. Co-stimulation with losartan and ANG II induced the exclusive expression of 106 genes associated with DNA methylation or demethylation, cell differentiation, the developmental process, response to muscle stretch, and calcium ion transmembrane transport. These findings highlight the usefulness of UdRPC-derived podocytes in studying the RAAS pathway and nephrotoxicity in various kidney diseases.


Asunto(s)
Hipertensión , Podocitos , Humanos , Losartán/farmacología , Losartán/metabolismo , Angiotensina II/metabolismo , Podocitos/metabolismo , Redes Reguladoras de Genes , Receptor de Angiotensina Tipo 1/genética , Receptor de Angiotensina Tipo 1/metabolismo , Hipertensión/metabolismo
3.
Int J Mol Sci ; 24(9)2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37175937

RESUMEN

Acute kidney injury (AKI) is a major kidney disease with a poor clinical outcome. It is a common complication, with an incidence of 10-15% of patients admitted to hospital. This rate even increases for patients who are admitted to the intensive care unit, with an incidence of >50%. AKI is characterized by a rapid increase in serum creatinine, decrease in urine output, or both. The associated symptoms include feeling sick or being sick, diarrhoea, dehydration, decreased urine output (although occasionally the urine output remains normal), fluid retention causing swelling in the legs or ankles, shortness of breath, fatigue and nausea. However, sometimes acute kidney injury causes no signs or symptoms and is detected by lab tests. Therefore, the identification of cytokines for the early detection and diagnosis of AKI is highly desirable, as their application might enable the prevention of the progression from AKI to chronic kidney disease (CKD). In this study, we analysed the secretome of the urine of an AKI patient cohort by employing a kidney-biomarker cytokine assay. Based on these results, we suggest ADIPOQ, EGF and SERPIN3A as potential cytokines that might be able to detect AKI as early as 24 h post-surgery. For the later stages, as common cytokines for the detection of AKI in both male and female patients, we suggest VEGF, SERPIN3A, TNFSF12, ANPEP, CXCL1, REN, CLU and PLAU. These cytokines in combination might present a robust strategy for identifying the development of AKI as early as 24 h or 72 h post-surgery. Furthermore, we evaluated the effect of patient and healthy urine on human podocyte cells. We conclude that cytokines abundant in the urine of AKI patients trigger processes that are needed to repair the damaged nephron and activate TP53 and SIRT1 to maintain the balance between proliferation, angiogenesis, and cell cycle arrest.


Asunto(s)
Lesión Renal Aguda , Podocitos , Humanos , Masculino , Femenino , Citocinas , Sirtuina 1 , Lesión Renal Aguda/etiología , Riñón , Creatinina , Biomarcadores/orina , Proteína p53 Supresora de Tumor
4.
Lancet ; 398(10317): 2160-2172, 2021 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-34798060

RESUMEN

BACKGROUND: Natural amylin is a pancreatic hormone that induces satiety. Cagrilintide is a long-acting amylin analogue under investigation for weight management. We assessed the dose-response relationship of cagrilintide regarding the effects on bodyweight, safety, and tolerability. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial at 57 sites including hospitals, specialist clinics, and primary care centres in ten countries (Canada, Denmark, Finland, Ireland, Japan, Poland, Serbia, South Africa, the UK, and the USA). Eligible participants were adults aged at least 18 years without diabetes, with a body-mass index of at least 30 kg/m2 or at least 27 kg/m2 with hypertension or dyslipidaemia. Participants were randomly assigned (6:1) to subcutaneous self-injections of once-weekly cagrilintide (0·3, 0·6, 1·2, 2·4, or 4·5 mg), once-daily liraglutide 3·0 mg, or volume-matched placebo (for six placebo groups). The trial had a 26-week treatment period, including a dose-escalation period of up to 6 weeks, and a 6-week follow-up period without treatment. Participants and investigators were masked to the assigned study treatment with respect to active versus pooled placebo treatment, but not to different active treatments. The primary endpoint was the percentage change in bodyweight from baseline to week 26, assessed in all randomly assigned participants according to the trial product estimand (assuming all participants were adherent to treatment) and to the treatment policy estimand (regardless of adherence to treatment). Safety was assessed in all participants who received at least one dose of randomised treatment. This trial is registered with ClinicalTrials.gov, NCT03856047, and is closed to new participants. FINDINGS: Between March 1 and Aug 19, 2019, we randomly assigned 706 participants to cagrilintide 0·3-4·5 mg (100-102 per dose group), 99 to liraglutide 3·0 mg, and 101 to placebo. Permanent treatment discontinuation (n=73 [10%]) occurred similarly across treatment groups, mostly due to adverse events (n=30 [4%]). In total, 29 participants (4%) withdrew from the trial. According to the trial product estimand, mean percentage weight reductions from baseline were greater with all doses of cagrilintide (0·3-4·5 mg, 6·0%-10·8% [6·4-11·5 kg]) versus placebo (3·0% [3·3 kg]; estimated treatment difference range 3·0%-7·8%; p<0·001). Weight reductions were also greater with cagrilintide 4·5 mg versus liraglutide 3·0 mg (10·8% [11·5 kg] vs 9·0% [9·6 kg]; estimated treatment difference 1·8%, p=0·03). Similar weight loss reductions were observed with the treatment policy estimand. The most frequent adverse events were gastrointestinal disorders (eg, nausea, constipation, and diarrhoea) and administration-site reactions. More participants receiving cagrilintide 0·3-4·5 mg had gastrointestinal adverse events compared with placebo (41%-63% vs 32%), primarily nausea (20%-47% vs 18%). INTERPRETATION: Treatment with cagrilintide in people with overweight and obesity led to significant reductions in bodyweight and was well tolerated. The findings support the development of molecules with novel mechanisms of action for weight management. FUNDING: Novo Nordisk A/S.


Asunto(s)
Relación Dosis-Respuesta a Droga , Polipéptido Amiloide de los Islotes Pancreáticos/uso terapéutico , Obesidad/tratamiento farmacológico , Pérdida de Peso/efectos de los fármacos , África , Índice de Masa Corporal , Método Doble Ciego , Europa (Continente) , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Inyecciones Subcutáneas , Liraglutida/administración & dosificación , Masculino , Persona de Mediana Edad , América del Norte
5.
Int J Mol Sci ; 23(15)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35955511

RESUMEN

Methyl group metabolism belongs to a relatively understudied field of research. Its importance lies in the fact that methyl group metabolic pathways are crucial for the successful conversion of dietary nutrients into the basic building blocks to carry out any cellular methylation reaction. Methyl groups play essential roles in numerous cellular functions such as DNA methylation, nucleotide- and protein biosynthesis. Especially, DNA methylation is responsible for organizing the genome into transcriptionally silent and active regions. Ultimately, it is this proper annotation that determines the quality of expression patterns required to ensure and shape the phenotypic integrity and function of a highly specialized cell type. Life is characterized by constantly changing environmental conditions, which are addressed by changes in DNA methylation. This relationship is increasingly coming into focus as it is of fundamental importance for differentiation, aging, and cancer. The stability and permanence of these metabolic processes, fueling the supplementation of methyl groups, seem to be important criteria to prevent deficiencies and erosion of the methylome. Alterations in the metabolic processes can lead to epigenetic and genetic perturbations, causative for diverse disorders, accelerated aging, and various age-related diseases. In recent decades, the intake of methyl group compounds has changed significantly due to, e.g., environmental pollution and food additives. Based on the current knowledge, this review provides a brief overview of the highly interconnected relationship between nutrition, metabolism, changes in epigenetic modifications, cancer, and aging. One goal is to provide an impetus to additionally investigate changes in DNA methylation as a possible consequence of an impaired methyl group metabolism.


Asunto(s)
Epigénesis Genética , Neoplasias , Envejecimiento/genética , Metilación de ADN , Epigenómica , Humanos , Neoplasias/genética
6.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36613831

RESUMEN

With approximately 1.4 million men annually diagnosed with prostate cancer (PCa) worldwide, PCa remains a dreaded threat to life and source of devastating morbidity. In recent decades, a significant decrease in age-specific PCa mortality has been achieved by increasing prostate-specific antigen (PSA) screening and improving treatments. Nevertheless, upcoming, augmented recommendations against PSA screening underline an escalating disproportion between the benefit and harm of current diagnosis/prognosis and application of radical treatment standards. Undoubtedly, new potent diagnostic and prognostic tools are urgently needed to alleviate this tensed situation. They should allow a more reliable early assessment of the upcoming threat, in order to enable applying timely adjusted and personalized therapy and monitoring. Here, we present a basic study on an epigenetic screening approach by Methylated DNA Immunoprecipitation (MeDIP). We identified genes associated with hypomethylated CpG islands in three PCa sample cohorts. By adjusting our computational biology analyses to focus on single CpG-enriched 60-nucleotide-long DNA probes, we revealed numerous consistently differential methylated DNA segments in PCa. They were associated among other genes with NOTCH3, CDK2AP1, KLK4, and ADAM15. These can be used for early discrimination, and might contribute to a new epigenetic tumor classification system of PCa. Our analysis shows that we can dissect short, differential methylated CpG-rich DNA fragments and combinations of them that are consistently present in all tumors. We name them tumor cell-specific differential methylated CpG dinucleotide signatures (TUMS).


Asunto(s)
Metilación de ADN , Neoplasias de la Próstata , Humanos , Masculino , Proteínas ADAM/genética , Islas de CpG , ADN , Proteínas de la Membrana/genética , Antígeno Prostático Específico/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología
7.
Int J Mol Sci ; 23(3)2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35163453

RESUMEN

Epigenetic mechanisms are fundamentally important for cancer initiation and development. However, a survey of the literature reveals that, to date, they appear less comprehensively investigated in melanoma than in many other cancers, e.g., prostate, breast, and colon carcinoma. The aim of this review is to provide a short summary of epigenetic aspects of functional relevance for melanoma pathogenesis. In addition, some new perspectives from epigenetic research in other cancers with potential for melanoma diagnosis and therapy are introduced. For example, the PrimeEpiHit hypothesis in urothelial carcinoma, which, similarly to malignant melanoma, can also be triggered by a single exogenous noxa, states that one of the first steps for cancer initiation could be epigenetic changes in key genes of one-carbon metabolism. The application of such insights may contribute to further progress in the diagnosis and therapy of melanoma, a deadly type of cancer.


Asunto(s)
Epigénesis Genética , Redes Reguladoras de Genes , Melanoma/genética , Metilación de ADN , Detección Precoz del Cáncer , Humanos , Melanoma/diagnóstico , Melanoma/terapia
8.
Int J Mol Sci ; 21(12)2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32630447

RESUMEN

Genes associated with immune response and inflammation have been identified as genetic risk factors for late-onset Alzheimer´s disease (LOAD). The rare R47H variant within triggering receptor expressed on myeloid cells 2 (TREM2) has been shown to increase the risk for developing Alzheimer's disease (AD) 2-3-fold. Here, we report the generation and characterization of a model of late-onset Alzheimer's disease (LOAD) using lymphoblast-derived induced pluripotent stem cells (iPSCs) from patients carrying the TREM2 R47H mutation, as well as from control individuals without dementia. All iPSCs efficiently differentiated into mature neuronal cultures, however AD neuronal cultures showed a distinct gene expression profile. Furthermore, manipulation of the iPSC-derived neuronal cultures with an Aß-S8C dimer highlighted metabolic pathways, phagosome and immune response as the most perturbed pathways in AD neuronal cultures. Through the construction of an Aß-induced gene regulatory network, we were able to identify an Aß signature linked to protein processing in the endoplasmic reticulum (ER), which emphasized ER-stress, as a potential causal role in LOAD. Overall, this study has shown that our AD-iPSC based model can be used for in-depth studies to better understand the molecular mechanisms underlying the etiology of LOAD and provides new opportunities for screening of potential therapeutic targets.


Asunto(s)
Enfermedad de Alzheimer/genética , Glicoproteínas de Membrana/genética , Receptores Inmunológicos/genética , Anciano , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Diferenciación Celular/genética , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Femenino , Redes Reguladoras de Genes/genética , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Modelos Biológicos , Mutación/genética , Células Mieloides/metabolismo , Neuronas/metabolismo , Células Madre Pluripotentes/metabolismo , Células Madre Pluripotentes/fisiología , Receptores Inmunológicos/metabolismo
9.
Diabetes Obes Metab ; 20(7): 1615-1622, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29493118

RESUMEN

AIM: To investigate the mechanisms behind the lower postprandial glucose (PPG) concentrations achieved with fast-acting insulin aspart (faster aspart) than with insulin aspart (IAsp). MATERIALS AND METHODS: In a randomized, double-blind, crossover trial, 41 people with type 1 diabetes received identical subcutaneous single faster aspart and IAsp doses (individualized for each participant), together with a standardized mixed meal (including 75 g carbohydrate labelled with [1-13 C] glucose). PPG turnover was determined by the triple-tracer meal method using continuous, variable [6-3 H] glucose and [6,6-2 H2 ] glucose infusion. RESULTS: Insulin exposure within the first hour was 32% greater with faster aspart than with IAsp (treatment ratio faster aspart/IAsp 1.32 [95% confidence interval {CI} 1.18;1.48]; P < .001), leading to a 0.59-mmol/L non-significantly smaller PPG increment at 1 hour (ΔPG1h ; treatment difference faster aspart-IAsp -0.59 mmol/L [95% CI -1.19; 0.01]; P = .055). The trend towards reduced ΔPG1h with faster aspart was attributable to 12% greater suppression of endogenous glucose production (EGP; treatment ratio 1.12 [95% CI 1.01; 1.25]; P = .040) and 23% higher glucose disappearance (1.23 [95% CI 1.05; 1.45]; P = .012) with faster aspart than with IAsp during the first hour. Suppression of free fatty acid levels during the first hour was 36% greater for faster aspart than for IAsp (1.36 [95% CI 1.01;1.88]; P = .042). CONCLUSIONS: The trend towards improved PPG control with faster aspart vs IAsp in this study was attributable to both greater early suppression of EGP and stimulation of glucose disappearance.


Asunto(s)
Glucemia/análisis , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Composición de Medicamentos , Gluconeogénesis/efectos de los fármacos , Hiperglucemia/prevención & control , Hipoglucemiantes/uso terapéutico , Insulina Aspart/uso terapéutico , Adulto , Isótopos de Carbono , Estudios Cruzados , Deuterio , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/metabolismo , Método Doble Ciego , Ácidos Grasos no Esterificados/sangre , Femenino , Estudios de Seguimiento , Humanos , Hipoglucemiantes/sangre , Hipoglucemiantes/metabolismo , Hipoglucemiantes/farmacocinética , Insulina Aspart/sangre , Insulina Aspart/metabolismo , Insulina Aspart/farmacocinética , Masculino , Persona de Mediana Edad , Periodo Posprandial , Tritio
10.
Pediatr Diabetes ; 18(8): 903-910, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28165180

RESUMEN

BACKGROUND: Faster-acting insulin aspart (faster aspart) is insulin aspart (IAsp) in a new formulation with additional excipients (L-arginine and niacinamide). In adults, faster aspart provides faster onset and greater early exposure and action vs IAsp. AIM: This randomized, double-blind, 2-period crossover trial investigated the pharmacological properties of faster aspart vs IAsp in 12 children (6-11 years), 13 adolescents (12-17 years), and 15 adults (18-64 years) with type 1 diabetes mellitus. METHODS: Subjects received 0.2 U/kg subcutaneous dosing (mean of 8.3, 12.8, and 15.6 U, respectively) immediately prior to a standardized meal (17.3 g carbohydrate/100 mL; amount adjusted by body weight). RESULTS: Consistently across age groups, onset of appearance occurred approximately twice-as-fast (5-7 minutes earlier) and early exposure (AUCIAsp,0-30min ; area under the IAsp curve from 0 to 30 minutes) was greater (by 78%-147%) for faster aspart vs IAsp, with no treatment differences in total exposure (AUCIAsp,0-t ) or maximum concentration (C max ). Two-hour postmeal plasma glucose excursion was reduced for faster aspart vs IAsp (although only reaching statistical significance in children). In accordance with the absolute dose administered for each age group, AUCIAsp,0-t for faster aspart was lower in children (estimated ratio children/adults [95% confidence interval]: 0.59 [0.50;0.69], P < .001) and adolescents (0.78 [0.67;0.90], P = .002) vs adults. No age group differences were seen in C max (0.91 [0.70;1.17], P = .445, and 0.99 [0.77;1.26], P = .903). The age effect on AUCIAsp,0-t and C max did not differ statistically significantly between treatments. Faster aspart and IAsp were well-tolerated. CONCLUSION: The current findings in children and adolescents suggest a potential for faster aspart to improve postprandial glycemia over current rapid-acting insulins also in younger age groups. http://ClinicalTrials.gov identifier: NCT02035371.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/uso terapéutico , Insulina Aspart/farmacocinética , Insulina Aspart/uso terapéutico , Adolescente , Factores de Edad , Glucemia/efectos de los fármacos , Niño , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Adulto Joven
11.
Parasitol Res ; 116(5): 1463-1477, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28315013

RESUMEN

Epigenetic mechanisms such as DNA methylation are increasingly recognized to be critical for vaccination efficacy and outcome of different infectious diseases, but corresponding information is scarcely available for host defense against malaria. In the experimental blood-stage malaria Plasmodium chabaudi, we investigate the possible effects of a blood-stage vaccine on DNA methylation of gene promoters in the liver, known as effector against blood-stage malaria, using DNA methylation microarrays. Naturally susceptible Balb/c mice acquire, by protective vaccination, the potency to survive P. chabaudi malaria and, concomitantly, modifications of constitutive DNA methylation of promoters of numerous genes in the liver; specifically, promoters of 256 genes are hyper(=up)- and 345 genes are hypo(=down)-methylated (p < 0.05). Protective vaccination also leads to changes in promoter DNA methylation upon challenge with P. chabaudi at peak parasitemia on day 8 post infection (p.i.), when 571 and 1013 gene promoters are up- and down-methylated, respectively, in relation to constitutive DNA methylation (p < 0.05). Gene set enrichment analyses reveal that both vaccination and P. chabaudi infections mainly modify promoters of those genes which are most statistically enriched with functions relating to regulation of transcription. Genes with down-methylated promoters encompass those encoding CX3CL1, GP130, and GATA2, known to be involved in monocyte recruitment, IL-6 trans-signaling, and onset of erythropoiesis, respectively. Our data suggest that vaccination may epigenetically improve parts of several effector functions of the liver against blood-stage malaria, as, e.g., recruitment of monocyte/macrophage to the liver accelerated liver regeneration and extramedullary hepatic erythropoiesis, thus leading to self-healing of otherwise lethal P. chabaudi blood-stage malaria.


Asunto(s)
Metilación de ADN/genética , Hígado/metabolismo , Macrófagos/inmunología , Vacunas contra la Malaria/inmunología , Malaria/inmunología , Monocitos/inmunología , Plasmodium chabaudi/inmunología , Animales , Quimiocina CX3CL1/biosíntesis , Quimiocina CX3CL1/genética , Receptor gp130 de Citocinas/biosíntesis , Receptor gp130 de Citocinas/genética , Epigénesis Genética , Femenino , Factor de Transcripción GATA2/biosíntesis , Factor de Transcripción GATA2/genética , Interleucina-6/genética , Malaria/parasitología , Malaria/prevención & control , Ratones , Ratones Endogámicos BALB C , Análisis de Secuencia por Matrices de Oligonucleótidos , Parasitemia/inmunología , Regiones Promotoras Genéticas/genética , Vacunación
12.
Cancers (Basel) ; 16(10)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38792020

RESUMEN

Based on the impressive success of Car-T-cell therapy in the treatment of hematological malignancies, a broad application for solid tumors also appears promising. However, some important hurdles need to be overcome. One of these is certainly the identification of specific target antigens on cancer cells. Hypomethylation is a characteristic epigenetic aberration in many tumor entities. Genome-wide screenings for consistent DNA hypomethylations in tumors enable the identification of aberrantly upregulated transcripts, which might result in cell surface proteins. Thus, this approach provides a new perspective for the discovery of potential new Car-T-cell target antigens for almost every tumor entity. First, we focus on this approach as a possible treatment for prostate cancer.

13.
Am J Physiol Renal Physiol ; 304(3): F268-78, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23136002

RESUMEN

This study aimed to estimate the relationship between pharmacokinetics and the antidiuretic effect of desmopressin. In the investigator-blind, randomized, parallel group study, 5 dose groups and 1 placebo group, each consisting of 12 healthy, overhydrated, nonsmoking male subjects 18-55 yr of age were infused intravenously over 2 h with placebo or 30, 60, 125, 250, and 500 ng desmopressin in 50 ml of normal saline. Plasma desmopressin and urine osmolality rose by variable amounts during the infusions of 60, 125, 250, and 500 ng desmopressin. Plotting mean urine osmolality against the concurrent mean plasma desmopressin yielded a temporal delay between pharmacokinetic (PK) and -dynamic (PD) responses in all dose groups. Using simulation from the indirect-response model, assuming a constant (4 ng/ml) desmopressin concentration, this delay between PK and PD was estimated at 4 h (10th-90th percentile: 1.8-8.1). Within each group, however, there were large individual variations (2- to 10-fold) in the magnitude and duration of the antidiuretic effect. The antidiuretic effect of intravenous desmopressin in water-loaded healthy adults varies considerably due largely to factors other than individual differences in pharmacokinetics. The antidiuretic effect is time as well as dose dependent and may be self-amplifying. The most likely explanation for these findings is that the time required for a given level of plasma desmopressin to exert its maximum antidiuretic effect varies markedly from person to person due to individual differences in the kinetics of one or more of the intracellular mechanisms that promote the reabsorption of solute-free water by principal cells in renal collecting tubules.


Asunto(s)
Fármacos Antidiuréticos/farmacología , Fármacos Antidiuréticos/farmacocinética , Desamino Arginina Vasopresina/farmacología , Desamino Arginina Vasopresina/farmacocinética , Diuresis/efectos de los fármacos , Orina/fisiología , Adolescente , Adulto , Fármacos Antidiuréticos/sangre , Presión Sanguínea/efectos de los fármacos , Desamino Arginina Vasopresina/sangre , Relación Dosis-Respuesta a Droga , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Concentración Osmolar , Método Simple Ciego , Factores de Tiempo , Adulto Joven
14.
Cells ; 12(3)2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36766685

RESUMEN

Recent demographic studies predict there will be a considerable increase in the number of elderly people within the next few decades. Aging has been recognized as one of the main risk factors for the world's most prevalent diseases such as neurodegenerative disorders, cancer, cardiovascular disease, and metabolic diseases. During the process of aging, a gradual loss of tissue volume and organ function is observed, which is partially caused by replicative senescence. The capacity of cellular proliferation and replicative senescence is tightly regulated by their telomere length. When telomere length is critically shortened with progressive cell division, cells become proliferatively arrested, and DNA damage response and cellular senescence are triggered, whereupon the "Hayflick limit" is attained at this stage. Podocytes are a cell type found in the kidney glomerulus where they have major roles in blood filtration. Mature podocytes are terminal differentiated cells that are unable to undergo cell division in vivo. For this reason, the establishment of primary podocyte cell cultures has been very challenging. In our present study, we present the successful immortalization of a human podocyte progenitor cell line, of which the primary cells were isolated directly from the urine of a 51-year-old male. The immortalized cell line was cultured over the course of one year (~100 passages) with high proliferation capacity, endowed with contact inhibition and P53 expression. Furthermore, by immunofluorescence-based expression and quantitative real-time PCR for the podocyte markers CD2AP, LMX1B, NPHS1, SYNPO and WT1, we confirmed the differentiation capacity of the immortalized cells. Finally, we evaluated and confirmed the responsiveness of the immortalized cells on the main mediator angiotensin II (ANGII) of the renin-angiotensin system (RAAS). In conclusion, we have shown that it is possible to bypass cellular replicative senescence (Hayflick limit) by TERT-driven immortalization of human urine-derived pre-podocyte cells from a 51-year-old African male.


Asunto(s)
Angiotensina II , Sistema Renina-Angiotensina , Masculino , Humanos , Anciano , Persona de Mediana Edad , Angiotensina II/farmacología , Línea Celular , Células Cultivadas , Senescencia Celular/genética
15.
Aging (Albany NY) ; 14(20): 8179-8204, 2022 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-36170022

RESUMEN

The aging process is manifested by a multitude of inter-linked biological processes. These processes contribute to genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, de-regulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. The mammalian ortholog of the yeast silent information regulator (Sir2) SIRT1 is a NAD+-dependent class III histone deacetylase and has been recognized to be involved in many of the forementioned processes. Furthermore, the physiological activity of several Sirtuin family members has been connected to the regulation of life span of lower organisms (Caenorhabditis elegans and Drosophila melanogaster) as well as mammals. In the present study, we provide evidence that SIX2-positive urine derived renal progenitor cells-UdRPCs isolated directly from human urine show typical hallmarks of aging. This includes the subsequent transcriptional downregulation of SIRT1 and its downstream targets AKT and GSK3ß with increased donor age. This transcriptional downregulation is accompanied by an increase in DNA damage and transcriptional levels of several cell cycle inhibitors such as P16. We provide evidence that the renal progenitor transcription factor SIX2 binds to the coding sequence of SIRT1. Furthermore, we show that the SIRT1 promoter region is methylation sensitive and becomes methylated during aging, dividing them into SIRT1-high and -low expressing UdRPCs. Our results highlight the importance of SIRT1 in DNA damage repair recognition in UdRPCs and the control of differentiation by regulating the activation of GSK3ß through AKT.


Asunto(s)
Daño del ADN , Sirtuina 1 , Células Madre , Humanos , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sirtuina 1/genética , Sirtuina 1/metabolismo , Células Madre/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Envejecimiento , Regiones Promotoras Genéticas , Metilación de ADN
17.
Cells ; 11(4)2022 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-35203286

RESUMEN

Kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD), which can progress to end stage renal disease (ESRD), are a worldwide health burden. Organ transplantation or kidney dialysis are the only effective available therapeutic tools. Therefore, in vitro models of kidney diseases and the development of prospective therapeutic options are urgently needed. Within the kidney, the glomeruli are involved in blood filtration and waste excretion and are easily affected by changing cellular conditions. Puromycin aminonucleoside (PAN) is a nephrotoxin, which can be employed to induce acute glomerular damage and to model glomerular disease. For this reason, we generated kidney organoids from three iPSC lines and treated these with PAN in order to induce kidney injury. Morphological observations revealed the disruption of glomerular and tubular structures within the kidney organoids upon PAN treatment, which were confirmed by transcriptome analyses. Subsequent analyses revealed an upregulation of immune response as well as inflammatory and cell-death-related processes. We conclude that the treatment of iPSC-derived kidney organoids with PAN induces kidney injury mediated by an intertwined network of inflammation, cytoskeletal re-arrangement, DNA damage, apoptosis and cell death. Furthermore, urine-stem-cell-derived kidney organoids can be used to model kidney-associated diseases and drug discovery.


Asunto(s)
Lesión Renal Aguda , Células Madre Pluripotentes Inducidas , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/metabolismo , Humanos , Riñón , Organoides/metabolismo , Puromicina Aminonucleósido/metabolismo , Puromicina Aminonucleósido/farmacología
18.
Cells ; 11(7)2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35406662

RESUMEN

High blood pressure is one of the major public health problems that causes severe disorders in several tissues including the human kidney. One of the most important signaling pathways associated with the regulation of blood pressure is the renin-angiotensin system (RAS), with its main mediator angiotensin II (ANGII). Elevated levels of circulating and intracellular ANGII and aldosterone lead to pro-fibrotic, -inflammatory, and -hypertrophic milieu that causes remodeling and dysfunction in cardiovascular and renal tissues. Furthermore, ANGII has been recognized as a major risk factor for the induction of apoptosis in podocytes, ultimately leading to chronic kidney disease (CKD). In the past, disease modeling of kidney-associated diseases was extremely difficult, as the derivation of kidney originated cells is very challenging. Here we describe a differentiation protocol for reproducible differentiation of sine oculis homeobox homolog 2 (SIX2)-positive urine-derived renal progenitor cells (UdRPCs) into podocytes bearing typical cellular processes. The UdRPCs-derived podocytes show the activation of the renin-angiotensin system by being responsive to ANGII stimulation. Our data reveal the ANGII-dependent downregulation of nephrin (NPHS1) and synaptopodin (SYNPO), resulting in the disruption of the podocyte cytoskeletal architecture, as shown by immunofluorescence-based detection of α-Actinin. Furthermore, we show that the cytoskeletal disruption is mainly mediated through angiotensin II receptor type 1 (AGTR1) signaling and can be rescued by AGTR1 inhibition with the selective, competitive angiotensin II receptor type 1 antagonist, losartan. In the present manuscript we confirm and propose UdRPCs differentiated to podocytes as a unique cell type useful for studying nephrogenesis and associated diseases. Furthermore, the responsiveness of UdRPCs-derived podocytes to ANGII implies potential applications in nephrotoxicity studies and drug screening.


Asunto(s)
Enfermedades Renales , Podocitos , Angiotensina II/metabolismo , Angiotensina II/farmacología , Humanos , Riñón/metabolismo , Enfermedades Renales/metabolismo , Losartán/farmacología , Podocitos/metabolismo , Sistema Renina-Angiotensina
19.
J Pers Med ; 13(1)2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36675700

RESUMEN

Chronic kidney disease (CKD) is a global health burden with a continuously increasing prevalence associated with an increasing incidence of diabetes and hypertension in aging populations. CKD is characterized by low glomerular filtration rate (GFR) and other renal impairments including proteinuria, thus implying that multiple factors may contribute to the etiology this disease. While there are indications of ethnic differences, it is hard to disentangle these from confounding social factors. Usually, CKD is detected in later stages of the disease when irreversible renal damage has already occurred, thus suggesting a need for early non-invasive diagnostic markers. In this study, we explored the urine secretome of a CKD patient cohort from Ghana with 40 gender-matched patients and 40 gender-matched healthy controls employing a kidney injury and a more general cytokine assay. We identified panels of kidney-specific cytokine markers, which were also gender-specific, and a panel of gender-independent cytokine markers. The gender-specific markers are IL10 and MME for male and CLU, RETN, AGER, EGFR and VEGFA for female. The gender-independent cytokine markers were APOA1, ANGPT2, C5, CFD, GH1, ICAM1, IGFBP2, IL8, KLK4, MMP9 and SPP1 (up-regulated) and FLT3LG, CSF1, PDGFA, RETN and VEGFA (down-regulated). APOA1-the major component of HDL particles-was up-regulated in Ghanaian CKD patients and its co-occurrence with APOL1 in a subpopulation of HDL particles may point to specific CKD-predisposing APOL1 haplotypes in patients of African descent-this, however, needs further investigation. The identified panels, though preliminary, lay down the foundation for the development of robust CKD-diagnostic assays.

20.
Cancers (Basel) ; 14(18)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36139544

RESUMEN

BACKGROUND: Although DNA methylation in the gene promoters usually represses gene expression, the TERT hypermethylated oncological region (THOR) located 5' of the hTERT gene is hypermethylated when hTERT is expressed in diverse cancer types, including urothelial cancer (UC). METHODS: Comprehensive MeDIP and DNA methylation array analyses complemented by the technically independent method of bisulfite genomic sequencing were applied on pathologically reviewed and classified urothelial carcinoma specimens and healthy urothelial tissue samples to reveal the methylation status of THOR in detail. RESULTS: The detailed DNA methylation profiles reveal the exact positions of differentially methylated CpG dinucleotides within THOR in urothelial cancer and provide evidence ofa diverging role of methylation of these CpGs in the regulation of hTERT. In particular, our data suggest a regulating mechanism in which THOR methylation acts on hTERT expression through epigenetic silencing of the lncRNA hTERT antisense promoter-associated (hTAPAS), which represses hTERT. CONCLUSIONS: These findings precisely define the most differentially methylated CpGs of THOR in early urothelial cancer, enabling optimal design of Methylation-Specific PCR (MSPCR) primers to reliably probe these methylation differences for diagnostic and prognostic purposes. In addition, this strategy presents a prime example that is also applicable to many other malignancies. Finally, the first evidence for the underlying epigenetic mechanism regulating hTERT expression through the methylation status of THOR is provided.

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