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1.
Diabetologia ; 66(1): 163-173, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36201044

RESUMO

AIMS/HYPOTHESIS: Islet transplantation has been studied in small cohorts of recipients with type 1 diabetes complicated by severe hypoglycaemic events (SHEs). We determined factors associated with favourable outcomes in a large cohort of recipients reported to the Collaborative Islet Transplant Registry (CITR). METHODS: In 398 non-uraemic islet transplant alone (ITA) recipients with type 1 diabetes and SHEs, transplanted between 1999 and 2015 and with at least 1 year follow-up, we analysed specified favourable outcomes against each of all available characteristics of pancreas donors, islet grafts, recipients and immunosuppressive regimens, as well as immunosuppression and procedure-related serious adverse events (SAEs). RESULTS: Four factors were associated with the highest rates of favourable outcomes: recipient age ≥35 years; total infused islets ≥325,000 islet equivalents; induction immunosuppression with T cell depletion and/or TNF-α inhibition; and maintenance with both mechanistic target of rapamycin (mTOR) and calcineurin inhibitors. At 5 years after the last islet infusion, of the recipients meeting these four common favourable factors (4CFF; N=126), 95% were free of SHEs, 76% had HbA1c <53 mmol/mol (7.0%), 73% had HbA1c <53 mmol/mol (7.0%) and absence of SHEs, and 53% were insulin independent, significantly higher rates than in the remaining recipients (<4CFF; N=272). The incidence of procedural and immunosuppression-related SAEs per recipient that resulted in sequelae, disability or death was low in both the 4CFF (0.056 per person) and <4CFF (0.074 per person) groups. CONCLUSIONS/INTERPRETATION: In recipients with type 1 diabetes complicated by SHEs, islet transplantation meeting 4CFF protected 95% from SHEs at 5 years after the last islet infusion and exerted a large and significant benefit on glycaemic control, with an acceptable safety profile for this subgroup of type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Humanos , Adulto , Transplante das Ilhotas Pancreáticas/efeitos adversos
2.
Muscle Nerve ; 68(3): 329-333, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37439375

RESUMO

INTRODUCTION/AIMS: Pancreatic islet transplantation (ITx) is increasingly used in patients with brittle type 1 diabetes (T1D). If successful, ITx results in insulin-free euglycemia, but its application is limited by a need for lifelong immunosuppression. The aim of this study was to assess the long-term effects of ITx on the occurrence and course of polyneuropathy in a cohort of patients with brittle T1D. METHODS: In this prospective, single-center study, 13 patients (4 males and 9 females) with brittle T1D had a baseline neurological exam with the calculation of Utah Neuropathy Scale (UNS) and a limited nerve conduction study before ITx, and about yearly after in the patients who achieved insulin independence. RESULTS: Patients were followed for a period of 17 to 133 months. There was no significant difference between UNS and nerve conduction study parameters at baseline and at the end of follow-up, except for significant decreases in peroneal (50.34 ± 6.12 vs. 52.42 ± 6.47 ms, P = 0.005) and ulnar (27.5 ± 2.15 vs. 29.45 ± 2.10 ms, P = 0.009) F-wave latencies and an increase in ulnar sensory nerve conduction velocity (49.98 ± 6.27 vs. 47.19 ± 5.36 m/s, P = 0.04). DISCUSSION: If successful, ITx has a good long-term safety profile for peripheral nerve toxicity, and a favorable effect on diabetic neuropathy.


Assuntos
Diabetes Mellitus Tipo 1 , Neuropatias Diabéticas , Transplante das Ilhotas Pancreáticas , Polineuropatias , Masculino , Feminino , Humanos , Transplante das Ilhotas Pancreáticas/métodos , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/cirurgia , Estudos Prospectivos , Insulina , Condução Nervosa
3.
Pancreatology ; 22(1): 1-8, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34620552

RESUMO

BACKGROUND: Total pancreatectomy with islet autotransplantation (TPIAT) is a viable option for treating debilitating recurrent acute pancreatitis (RAP) and chronic pancreatitis (CP) in adults and children. No data is currently available regarding variation in approach to operation. METHODS: We evaluated surgical techniques, islet isolation and infusion approaches, and outcomes and complications, comparing children (n = 84) with adults (n = 195) enrolled between January 2017 and April 2020 by 11 centers in the United States in the Prospective Observational Study of TPIAT (POST), which was launched in 2017 to collect standard history and outcomes data from patients undergoing TPIAT for RAP or CP. RESULTS: Children more commonly underwent splenectomy (100% versus 91%, p = 0.002), pylorus preservation (93% versus 67%; p < 0.0001), Roux-en-Y duodenojejunostomy reconstruction (92% versus 35%; p < 0.0001), and enteral feeding tube placement (93% versus 63%; p < 0.0001). Median islet equivalents/kg transplanted was higher in children (4577; IQR 2816-6517) than adults (2909; IQR 1555-4479; p < 0.0001), with COBE purification less common in children (4% versus 15%; p = 0.0068). Median length of hospital stay was higher in children (15 days; IQR 14-22 versus 11 days; IQR 8-14; p < 0.0001), but 30-day readmissions were lower in children (13% versus 26%, p = 0.018). Rate of portal vein thrombosis was significantly lower in children than in adults (2% versus 10%, p = 0.028). There were no mortalities in the first 90 days post-TPIAT. CONCLUSIONS: Pancreatectomy techniques differ between children and adults, with islet yields higher in children. The rates of portal vein thrombosis and early readmission are lower in children.


Assuntos
Transplante das Ilhotas Pancreáticas , Laparoscopia , Pancreatectomia , Pancreatite Crônica/cirurgia , Doença Aguda , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Transplante Autólogo , Resultado do Tratamento
4.
Sensors (Basel) ; 22(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36146411

RESUMO

The article presents the use of barometric sensors to precisely determine the altitude of a flying object. The sensors are arranged in a hexahedral spatial arrangement with appropriately spaced air inlets. Thanks to the solution used, the range of measurement uncertainty can be reduced, resulting in a lower probability of error during measurement by improving the accuracy of estimation. The paper also describes the use of pressure sensors in complex Tracking Vertical Velocity and Height systems, integrating different types of sensors to highlight the importance of this single parameter. The solution can find application in computational systems using different types of data in Kalman filters. The impact of pressure measurements in a geometric system with different spatial orientations of sensors is also presented. In order to compensate for local pressure differences, e.g., in the form of side wind gusts, an additional reference sensor was used, making the developed solution relevant for applications such as industrial ones.


Assuntos
Altitude , Vento
5.
Am J Transplant ; 21(11): 3714-3724, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34033222

RESUMO

Several cytokines and chemokines are elevated after islet infusion in patients undergoing total pancreatectomy with islet autotransplantation (TPIAT), including CXCL8 (also known as interleukin-8), leading to islet loss. We investigated whether use of reparixin for blockade of the CXCL8 pathway would improve islet engraftment and insulin independence after TPIAT. Adults without diabetes scheduled for TPIAT at nine academic centers were randomized to a continuous infusion of reparixin or placebo (double-blinded) for 7 days in the peri-transplant period. Efficacy measures included insulin independence (primary), insulin dose, hemoglobin A1c (HbA1c ), and mixed meal tolerance testing. The intent-to-treat population included 102 participants (age 39.5 ± 12.2 years, 69% female), n = 50 reparixin-treated, n = 52 placebo-treated. The proportion insulin-independent at Day 365 was similar in reparixin and placebo: 20% vs. 21% (p = .542). Twenty-seven of 42 (64.3%) in the reparixin group and 28/45 (62.2%) in the placebo group maintained HbA1c ≤6.5% (p = .842, Day 365). Area under the curve C-peptide from mixed meal testing was similar between groups, as were adverse events. In conclusion, reparixin infusion did not improve diabetes outcomes. CXCL8 inhibition alone may be insufficient to prevent islet damage from innate inflammation in islet autotransplantation. This first multicenter clinical trial in TPIAT highlights the potential for future multicenter collaborations.


Assuntos
Diabetes Mellitus , Transplante das Ilhotas Pancreáticas , Pancreatite Crônica , Receptores de Interleucina-8A/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Adulto , Peptídeo C , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Pancreatite Crônica/cirurgia , Transplantados , Transplante Autólogo , Resultado do Tratamento
6.
Am J Transplant ; 21(4): 1365-1375, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33251712

RESUMO

Islet allotransplantation in the United States (US) is facing an imminent demise. Despite nearly three decades of progress in the field, an archaic regulatory framework has stymied US clinical practice. Current regulations do not reflect the state-of-the-art in clinical or technical practices. In the US, islets are considered biologic drugs and "more than minimally manipulated" human cell and tissue products (HCT/Ps). In contrast, across the world, human islets are appropriately defined as "minimally manipulated tissue" and not regulated as a drug, which has led to islet allotransplantation (allo-ITx) becoming a standard-of-care procedure for selected patients with type 1 diabetes mellitus. This regulatory distinction impedes patient access to islets for transplantation in the US. As a result only 11 patients underwent allo-ITx in the US between 2016 and 2019, and all as investigational procedures in the settings of a clinical trials. Herein, we describe the current regulations pertaining to islet transplantation in the United States. We explore the progress which has been made in the field and demonstrate why the regulatory framework must be updated to both better reflect our current clinical practice and to deal with upcoming challenges. We propose specific updates to current regulations which are required for the renaissance of ethical, safe, effective, and affordable allo-ITx in the United States.


Assuntos
Produtos Biológicos , Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Custos e Análise de Custo , Diabetes Mellitus Tipo 1/cirurgia , Humanos , Transplante Heterólogo , Estados Unidos
7.
Pancreatology ; 21(1): 275-281, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33323311

RESUMO

BACKGROUND AND AIMS: Many patients undergoing total pancreatectomy with islet autotransplant (TPIAT) for severe, refractory chronic pancreatitis or recurrent acute pancreatitis have a history of endoscopic retrograde cholangiopancreatography (ERCP). Using data from the multicenter POST (Prospective Observational Study of TPIAT) cohort, we aimed to determine clinical characteristics associated with ERCP and the effect of ERCP on islet yield. METHODS: Using data from 230 participants (11 centers), demographics, pancreatitis history, and imaging features were tested for association with ERCP procedures. Logistic and linear regression were used to assess association of islet yield measures with having any pre-operative ERCPs and with the number of ERCPs, adjusting for confounders. RESULTS: 175 (76%) underwent ERCPs [median number of ERCPs (IQR) 2 (1-4). ERCP was more common in those with obstructed pancreatic duct (p = 0.0009), pancreas divisum (p = 0.0009), prior pancreatic surgery (p = 0.005), and longer disease duration (p = 0.004). A greater number of ERCPs was associated with disease duration (p < 0.0001), obstructed pancreatic duct (p = 0.006), and prior pancreatic surgery (p = 0.006) and increased risk for positive islet culture (p < 0.0001). Mean total IEQ/kg with vs. without prior ERCP were 4145 (95% CI 3621-4669) vs. 3476 (95% CI 2521-4431) respectively (p = 0.23). Adjusting for confounders, islet yield was not significantly associated with prior ERCP, number of ERCPs, biliary or pancreatic sphincterotomy or stent placement. CONCLUSIONS: ERCP did not appear to adversely impact islet yield. When indicated, ERCP need not be withheld to optimize islet yield but the risk-benefit ratio of ERCP should be considered given its potential harms, including risk for excessive delay in TPIAT.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/diagnóstico por imagem , Pancreatectomia/métodos , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatopatias/cirurgia , Pancreatite/cirurgia , Estudos Prospectivos , Recidiva , Adulto Jovem
8.
Clin Transplant ; 35(4): e14246, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33555058

RESUMO

Adverse clinical outcomes related to SARS-CoV-2 infection among liver transplant (LTx) recipients remain undefined. We performed a meta-analysis to determine the pooled prevalence of outcomes among hospitalized LTx recipients with COVID-19. A database search of literature published between December 1, 2019, and November 20, 2020, was performed per PRISMA guidelines. Twelve studies comprising 517 hospitalized LTx recipients with COVID-19 were analyzed. Common presenting symptoms were fever (71%), cough (62%), dyspnea (48%), and diarrhea (28%). Approximately 77% (95% CI, 61%-93%) of LTx recipients had a history of liver cirrhosis. The most prevalent comorbidities were hypertension (55%), diabetes (45%), and cardiac disease (21%). In-hospital mortality was 20% (95% CI, 13%-28%) and rose to 41% (95% CI, 19%-63%) (P < 0.00) with ICU admission. Additional subgroup analysis demonstrated a higher mortality risk in the elderly (>60-65 years) (OR 4.26; 95% CI, 2.14-8.49). There was no correlation in respect to sex or time since transplant. In summary, LTx recipients with COVID-19 had a high prevalence of dyspnea and gastrointestinal symptoms. In-hospital mortality was comparable to non-transplant populations with similar comorbidities but appeared to be less than what is reported elsewhere for cirrhotic patients (26%-40%). Importantly, the observed high case fatality in the elderly could be due to age-associated comorbidities.


Assuntos
COVID-19/epidemiologia , Transplante de Fígado , Transplantados , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/cirurgia , Feminino , Hospitalização , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade
9.
Pediatr Surg Int ; 37(10): 1383-1392, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34245339

RESUMO

BACKGROUND: Chronic pancreatitis (CP) and acute recurrent pancreatitis (ARP) in pediatric patients are strongly associated with genetic mutations and lead to pan-parenchymal disease refractory to medical and endoscopic treatment. Our aim was to assess pain resolution and glucose control in patients with CP and ARP following total pancreatectomy with islet auto-transplantation (TPIAT). METHODS: We retrospectively analyzed prospectively collected clinical data of 12 children who developed CP and ARP and underwent TPIAT when 21 years old or younger at the University of Chicago between December 2009 and June 2020. Patients with recurrent or persistent abdominal pain attributed to acute or chronic pancreatic inflammation and a history of medical interventions attempted for the relief of pancreatic pain were selected by a multi-disciplinary team for TPIAT. We followed patients post-operatively and reported data for pre-TPIAT, post-operative day 75, and yearly post-TPIAT. RESULTS: All 12 patients experienced complete resolution of pancreatic pain. The overall insulin-independence rate after 1 year was 66% (8/12) and 50% (3/6) at 4 years. Shorter duration of CP/ARP pre-TPIAT, higher mass of islets infused, and lower BMI, BMI percentile, and BSA were associated with insulin-independence post-TPIAT. CONCLUSIONS: TPIAT is a viable treatment option for pediatric patients with CP and ARP. Pediatric patients undergoing TPIAT for CP achieved resolution of pancreatic-type pain and reduced opioid requirements. The majority were able to achieve insulin-independence which was associated with lower pre-TPIAT BMI and higher islet mass transplanted (i.e., over 2000 IEQ/kg), the latter of which can be achieved by earlier TPIAT. LEVEL OF EVIDENCE: Treatment study, Level IV.


Assuntos
Glicemia , Pancreatite Crônica , Dor Abdominal , Criança , Humanos , Pancreatectomia , Pancreatite Crônica/cirurgia , Estudos Retrospectivos , Transplante Autólogo , Resultado do Tratamento
10.
Am J Transplant ; 20(3): 844-851, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31597009

RESUMO

This study aimed to evaluate whether the BETA-2 score is a reliable early predictor of graft decline and loss of insulin independence after islet allotransplantation. Islet transplant procedures were stratified into 3 groups according to clinical outcome: long-term insulin independence without islet graft decline (group 1, N = 9), initial insulin independence with subsequent islet graft decline and loss of insulin independence (group 2, N = 13), and no insulin independence (group 3, N = 13). BETA-2 was calculated on day 75 and multiple times afterwards for up to 145 months posttransplantation. A BETA-2 score cut-off of 17.4 on day 75 posttransplantation was discerned between group 1 and groups 2 and 3 (area under the receiver operating characteristic 0.769, P = .005) with a sensitivity and negative predictive value of 100%. Additionally, BETA-2 ≥ 17.4 at any timepoint during follow-up reflected islet function required for long-term insulin independence. While BETA-2 did not decline below 17.4 for each of the 9 cases from group 1, the score decreased below 17.4 for all transplants from group 2 with subsequent loss of insulin independence. The reduction of BETA-2 below 17.4 predicted 9 (1.5-21) months in advance subsequent islet graft decline and loss of insulin independence (P = .03). This finding has important implications for posttransplant monitoring and patient care.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Glicemia , Peptídeo C , Diabetes Mellitus Tipo 1/cirurgia , Humanos , Insulina
12.
Transpl Int ; 32(3): 280-290, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30353611

RESUMO

We investigated six indices based on a single fasting blood sample for evaluation of the beta-cell function after total pancreatectomy with islet autotransplantation (TP-IAT). The Secretory Unit of Islet Transplant Objects (SUITO), transplant estimated function (TEF), homeostasis model assessment (HOMA-2B%), C-peptide/glucose ratio (CP/G), C-peptide/glucose creatinine ratio (CP/GCr) and BETA-2 score were compared against a 90-min serum glucose level, weighted mean C-peptide in mixed meal tolerance test (MMTT), beta score and the Igls score adjusted for islet function in the setting of IAT. We analyzed values from 32 MMTTs in 15 patients after TP-IAT with a follow-up of up to 3 years. Four (27%) individuals had discontinued insulin completely prior to day 75, while 6 out of 12 patients (50%) did not require insulin support at 1-year follow-up with HbA1c 6.0% (5.5-6.8). BETA-2 was the most consistent among indices strongly correlating with all reference measures of beta-cell function (r = 0.62-0.68). In addition, it identified insulin independence (cut-off = 16.2) and optimal/good versus marginal islet function in the Igls score well, with AUROC of 0.85 and 0.96, respectively. Based on a single fasting blood sample, BETA-2 score has the most reliable discriminant value for the assessment of graft function in patients undergoing TP-IAT.


Assuntos
Jejum/sangue , Células Secretoras de Insulina/fisiologia , Transplante das Ilhotas Pancreáticas , Pancreatectomia , Adolescente , Adulto , Glicemia/análise , Peptídeo C/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Transplante Autólogo , Adulto Jovem
13.
Am J Transplant ; 18(4): 990-997, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29218834

RESUMO

Six single fasting blood sample-based indices-Secretory Unit of Islet Transplant Objects (SUITO), Transplant Estimated Function (TEF), Homeostasis Model Assessment (HOMA)2-B%, C-peptide/glucose ratio (CP/G), C-peptide/glucose creatinine ratio (CP/GCr), and BETA-2 score-were compared against commonly used 90-minute mixed meal tolerance test (MMTT) serum glucose and beta score to assess which of them best recognizes the state of acceptable blood glucose control without insulin supplementation after islet allotransplantation (ITx). We also tested whether the indices could identify the success of ITx based on the Igls classification of beta cell graft function. We analyzed values from 47 MMTT tests in 4 patients with up to 140 months follow-up and from 54 MMTT tests in 13 patients with up to 42 months follow-up. SUITO, CP/G, HOMA2-B%, and BETA-2 correlated well with the 90-minute glucose of the MMTT and beta-score (r 0.54-0.76), whereas CP/GCr showed a modest performance (r 0.41-0.52) while TEF showed little correlation. BETA-2 and SUITO were the best identifiers and predictors of the need for insulin support, glucose intolerance, and ITx success (P < .001), while HOMA2-B% and TEF were unreliable. Single fasting blood sample SUITO and BETA-2 scores are very practical alternative tools that allow for frequent assessments of graft function.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/terapia , Jejum/sangue , Sobrevivência de Enxerto , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/fisiologia , Adulto , Glicemia/análise , Peptídeo C/sangue , Estudos de Coortes , Feminino , Seguimentos , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico
14.
Pancreatology ; 18(3): 286-290, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29456124

RESUMO

BACKGROUND/OBJECTIVES: Total pancreatectomy with islet autotransplantation (TPIAT) is considered for managing chronic pancreatitis in selected patients when medical and endoscopic interventions have not provided adequate relief from debilitating pain. Although more centers are performing TPIAT, we lack large, multi-center studies to guide decisions about selecting candidates for and timing of TPIAT. METHODS: Multiple centers across the United States (9 to date) performing TPIAT are prospectively enrolling patients undergoing TPIAT for chronic pancreatitis into the Prospective Observational Study of TPIAT (POST), a NIDDK funded study with a goal of accruing 450 TPIAT recipients. Baseline data include participant phenotype, pancreatitis history, and medical/psychological comorbidities from medical records, participant interview, and participant self-report (Medical Outcomes Survey Short Form-12, EQ-5D, andPROMIS inventories for pain interference, depression, and anxiety). Outcome measures are collected to at least 1 year after TPIAT, including the same participant questionnaires, visual analog pain scale, pain interference scores, opioid requirements, insulin requirements, islet graft function, and hemoglobin A1c. Health resource utilization data are collected for a cost-effectiveness analysis. Biorepository specimens including urine, serum/plasma, genetic material (saliva and blood), and pancreas tissue are collected for future study. CONCLUSIONS: This ongoing multicenter research study will enroll and follow TPIAT recipients, aiming to evaluate patient selection and timing for TPIAT to optimize pain relief, quality of life, and diabetes outcomes, and to measure the procedure's cost-effectiveness. A biorepository is also established for future ancillary studies.


Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Pancreatectomia/métodos , Pancreatite/cirurgia , Análise Custo-Benefício , Diabetes Mellitus/economia , Diabetes Mellitus/cirurgia , Hemoglobinas Glicadas/análise , Humanos , Insulina/uso terapêutico , Transplante das Ilhotas Pancreáticas/economia , Medição da Dor , Dor Pós-Operatória/epidemiologia , Pancreatectomia/economia , Pancreatite/economia , Pancreatite/terapia , Estudos Prospectivos , Qualidade de Vida , Autorrelato , Inquéritos e Questionários , Transplante Autólogo , Resultado do Tratamento
16.
Hum Mol Genet ; 24(6): 1646-54, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25398947

RESUMO

Non-coding variation within TCF7L2 remains the strongest genetic determinant of type 2 diabetes risk in humans. A considerable effort has been placed in understanding the functional roles of TCF7L2 in pancreatic beta cells, despite evidence of TCF7L2 expression in various peripheral tissues important in glucose homeostasis. Here, we use a humanized mouse model overexpressing Tcf7l2, resulting in glucose intolerance, to infer the contribution of Tcf7l2 overexpression in beta cells and in other tissues to the metabolic phenotypes displayed by these mice. Restoring Tcf7l2 expression specifically in beta cells to endogenous levels, in face of its overexpression elsewhere, results in impaired insulin secretion, reduced beta cell number and islet area, corroborating data obtained in humans showing similar phenotypes as a result of manipulations leading to Tcf7l2 loss of function. Interestingly, the persistent overexpression of Tcf7l2 in non-pancreatic tissues results in a significant worsening in glucose tolerance in vivo, indicating that Tcf7l2 overexpression in beta cells does not account for the glucose intolerance in the Tcf7l2 overexpression mouse model. Collectively, these data posit that Tcf7l2 plays key roles in glucose metabolism through actions beyond pancreatic beta cells, and further points to functionally opposing cell-type specific effects for Tcf7l2 on the maintenance of balanced glucose metabolism, thereby urging a careful examination of its role in non-pancreatic tissues as well as its composite metabolic effects across distinct tissues. Uncovering these roles may lead to new therapeutic targets for type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/genética , Intolerância à Glucose/genética , Glucose/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Animais , Modelos Animais de Doenças , Expressão Gênica , Humanos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Camundongos , Camundongos Transgênicos , Regulação para Cima
17.
Mol Carcinog ; 56(4): 1344-1360, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27891679

RESUMO

Pancreatic cancer is one of the most lethal human malignancies. A better understanding of the intracellular mechanism of migration and invasion is urgently needed to develop treatment that will suppress metastases and improve overall survival. Cyclic adenosine monophosphate (cyclic AMP) is a second messenger that has shown to regulate migration and invasion of pancreatic cancer cells. The rise of cyclic AMP suppressed migration and invasion of pancreatic ductal adenocarcinoma cells. Cyclic AMP is formed from cytosolic ATP by the enzyme adenylyl cyclase (AC). There are ten isoforms of ACs; nine are anchored in the plasma membrane and one is soluble. What remains unknown is the extent to which the expression of transmembrane AC isoforms is both modified in pancreatic cancer and mediates the inhibitory effect of forskolin on cell motility. Using real-time PCR analysis, ADCY3 was found to be highly expressed in pancreatic tumor tissues, resulting in a constitutive increase in cyclic AMP levels. On the other hand, ADCY2 was down-regulated. Migration, invasion, and filopodia formation in two different pancreatic adenocarcinoma cell lines, HPAC and PANC-1 deficient in AC1 or AC3, were studied. We found that AC3, upon stimulation with forskolin, enhanced cyclic AMP levels and inhibited cell migration and invasion. Unlikely to be due to a cytotoxic effect, the inhibitory effects of forskolin involved the quick formation of AC3/adenylyl cyclase-associated protein 1 (CAP1)/G-actin complex, which inhibited filopodia formation and cell motility. Using Western blotting analysis, forskolin, through AC3 activation, caused phosphorylation of CREB, but not ERK. The effect of CREB phosphorylation is likely to be associated with long-term signaling changes. © 2016 Wiley Periodicals, Inc.


Assuntos
Adenilil Ciclases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Movimento Celular/efeitos dos fármacos , Colforsina/farmacologia , Proteínas do Citoesqueleto/metabolismo , Ativadores de Enzimas/farmacologia , Neoplasias Pancreáticas/metabolismo , Adenilil Ciclases/genética , Adulto , Idoso , Animais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Regulação para Cima
20.
J Transl Med ; 14(1): 332, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27903296

RESUMO

BACKGROUND: Recent studies suggest that immunotherapy using T regulatory cells (Tregs) prolongs remission in type 1 diabetes (T1DM). Here, we report factors that possibly affect the efficacy of this treatment. METHODS: The metabolic and immune background of 12 children with recently diagnosed T1DM, as well as that of untreated subjects, during a 2-year follow-up is presented. Patients were treated with up to 30 × 106/kg b.w. of autologous expanded CD3+CD4+CD25highCD127- Tregs. RESULTS: The disease progressed and all patients were insulin-dependent 2 years after inclusion. The ß-cell function measured by c-peptide levels and the use of insulin were the best preserved in patients treated with two doses of Tregs (3/6 in remission), less so after one dose (1/6 in remission) and the worst in untreated controls (no remissions). Increased levels of Tregs could be seen in peripheral blood after their adoptive transfer together with the shift from naïve CD62L+CD45RA+ to memory CD62L+CD45RA- Tregs. Increasing serum levels of proinflammatory cytokines were found: IL6 increased in all subjects, while IL1 and TNFα increased only in untreated group. Therapeutic Tregs were dependent on IL2, and their survival could be improved by other lymphocytes. CONCLUSIONS: The disease progression was associated with changing proportions of naïve and memory Tregs and slowly increasing proinflammatory activity, which was only partially controlled by the administered Tregs. The therapeutic cells were highly dependent on IL2. We conclude that the therapy should be administered at the earliest to protect the highest possible mass of islets and also to utilize the preserved content of Tregs in the earlier phases of T1DM. Trial registration http://www.controlled-trials.com/ISRCTN06128462 ; registered retrospectively.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/terapia , Linfócitos T Reguladores/imunologia , Adolescente , Autoanticorpos/sangue , Linfócitos B/imunologia , Biomarcadores/metabolismo , Sobrevivência Celular , Criança , Citocinas/sangue , Diabetes Mellitus Tipo 1/sangue , Progressão da Doença , Seguimentos , Humanos , Mediadores da Inflamação/sangue , Subpopulações de Linfócitos/imunologia , Fenótipo , Fatores de Tempo , Resultado do Tratamento
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