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1.
PLoS One ; 16(3): e0246265, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661932

RESUMO

Medicinal uses and applications of metals and their complexes are of increasing clinical and commercial importance. The ligation behavior of quercetin (Q), which is a flavonoid, and its Zn (II) (Q/Zn) complex were studied and characterized based on elemental analysis, molar conductance, Fourier-transform infrared (FTIR) spectra, electronic spectra, proton nuclear magnetic resonance (1H-NMR), thermogravimetric analysis, and transmission electron microscopy (TEM). FTIR spectral data revealed that Q acts as a bidentate ligand (chelating ligand) through carbonyl C(4) = O oxygen and phenolic C(3)-OH oxygen in conjugation with Zn. Electronic, FTIR, and 1H-NMR spectral data revealed that the Q/Zn complex has a distorted octahedral geometry, with the following chemical formula: [Zn(Q)(NO3)(H2O)2].5H2O. Diabetes was induced by streptozotocin (STZ) injection. A total of 70 male albino rats were divided into seven groups: control, diabetic untreated group and diabetic groups treated with either MSCs and/or Q and/or Q/Zn or their combination. Serum insulin, glucose, C-peptide, glycosylated hemoglobin, lipid profile, and enzymatic and non-enzymatic antioxidant levels were determined. Pancreatic and lung histology and TEM for pancreatic tissues in addition to gene expression of both SOD and CAT in pulmonary tissues were evaluated. MSCs in combination with Q/Zn therapy exhibited potent protective effects against STZ induced hyperglycemia and suppressed oxidative stress, genotoxicity, glycometabolic disturbances, and structural alterations. Engrafted MSCs were found inside pancreatic tissue at the end of the experiment. In conclusion, Q/Zn with MSC therapy produced a synergistic effect against oxidative stress and genotoxicity and can be considered potential ameliorative therapy against diabetes with pulmonary dysfunction, which may benefit against COVID-19.


Assuntos
Diabetes Mellitus Experimental/terapia , Hipoglicemiantes/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Quercetina/uso terapêutico , Zinco/uso terapêutico , Animais , Glicemia/análise , Glicemia/metabolismo , Peptídeo C/sangue , Peptídeo C/metabolismo , Células Cultivadas , Complexos de Coordenação/química , Complexos de Coordenação/uso terapêutico , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Hemoglobina A Glicada/análise , Hemoglobina A Glicada/metabolismo , Hiperglicemia/sangue , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Hiperglicemia/terapia , Hipoglicemiantes/química , Insulina/sangue , Insulina/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Quercetina/análogos & derivados , Ratos , Zinco/química
2.
Int J Mol Sci ; 21(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352955

RESUMO

Diabetes-related neuropathy is a debilitating condition that may be averted if it can be detected early. One possible way this can be achieved at low cost is to utilise peptides to detect C-peptide, a biomarker of diabetic neuropathy. This depends on peptide-peptide co-assembly, which is currently in a nascent stage of intense study. Instead, we propose a bead-based triple-overlay combinatorial strategy that can preserve inter-residue information during the screening process for a suitable complementary peptide to co-assemble with C-peptide. The screening process commenced with a pentapeptide general library, which revealed histidine to be an essential residue. Further screening with seven tetrapeptide focused libraries led to a table of self-consistent peptide sequences that included tryptophan and lysine at high frequencies. Three complementary nonapeptides (9mer com-peptides), wpkkhfwgq (Trp-D), kwkkhfwgq (Lys-D), and KWKKHFWGQ (Lys-L) (as a negative control) were picked from this table for co-assembly studies with C-peptide. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) and circular dichroism (CD) spectroscopies were utilized to study inter-peptide interactions and changes in secondary structures respectively. ATR-FTIR studies showed that there is indeed inter-peptide interaction between C-peptide and the tryptophan residues of the 9mer com-peptides. CD studies of unaggregated and colloidal C-peptide with the 9mer com-peptides suggest that the extent of co-assembly of C-peptide with Trp-D is greatest, followed by Lys-D and Lys-L. These results are promising and indicate that the presented strategy is viable for designing and evaluating longer complementary peptides, as well as complementary peptides for co-assembly with other polypeptides of interest and importance. We discuss the possibility of designing complementary peptides to inhibit toxic amyloidosis with this approach.


Assuntos
Peptídeos/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Biomarcadores , Peptídeo C/química , Peptídeo C/metabolismo , Dicroísmo Circular , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/metabolismo , Humanos , Peptídeos/metabolismo , Prognóstico , Ligação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Metabolism ; 111: 154324, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32712220

RESUMO

BACKGROUND: Clinical trials and animal studies have shown that sodium-glucose co-transporter type 2 (SGLT2) inhibitors improve pancreatic beta cell function. Our study aimed to investigate the effect of dapagliflozin on islet morphology and cell phenotype, and explore the origin and possible reason of the regenerated beta cells. METHODS: Two diabetic mouse models, db/db mice and pancreatic alpha cell lineage-tracing (glucagon-ß-gal) mice whose diabetes was induced by high fat diet combined with streptozotocin, were used. Mice were treated by daily intragastric administration of dapagliflozin (1 mg/kg) or vehicle for 6 weeks. The plasma insulin, glucagon and glucagon-like peptide-1 (GLP-1) were determined by using ELISA. The evaluation of islet morphology and cell phenotype was performed with immunofluorescence. Primary rodent islets and αTC1.9, a mouse alpha cell line, were incubated with dapagliflozin (0.25-25 µmol/L) or vehicle in the presence or absence of GLP-1 receptor antagonist for 24 h in regular or high glucose medium. The expression of specific markers and hormone levels were determined. RESULTS: Treatment with dapagliflozin significantly decreased blood glucose in the two diabetic models and upregulated plasma insulin and GLP-1 levels in db/db mice. The dapagliflozin treatment increased islet and beta cell numbers in the two diabetic mice. The beta cell proliferation as indicated by C-peptide and BrdU double-positive cells was boosted by dapagliflozin. The alpha to beta cell conversion, as evaluated by glucagon and insulin double-positive cells and confirmed by using alpha cell lineage-tracing, was facilitated by dapagliflozin. After the dapagliflozin treatment, some insulin-positive cells were located in the duct compartment or even co-localized with duct cell markers, suggestive of duct-derived beta cell neogenesis. In cultured primary rodent islets and αTC1.9 cells, dapagliflozin upregulated the expression of pancreatic endocrine progenitor and beta cell specific markers (including Pdx1) under high glucose condition. Moreover, dapagliflozin upregulated the expression of Pcsk1 (which encodes prohormone convertase 1/3, an important enzyme for processing proglucagon to GLP-1), and increased GLP-1 content and secretion in αTC1.9 cells. Importantly, the dapagliflozin-induced upregulation of Pdx1 expression was attenuated by GLP-1 receptor antagonist. CONCLUSIONS: Except for glucose-lowering effect, dapagliflozin has extra protective effects on beta cells in type 2 diabetes. Dapagliflozin enhances beta cell self-replication, induces alpha to beta cell conversion, and promotes duct-derived beta cell neogenesis. The promoting effects of dapagliflozin on beta cell regeneration may be partially mediated via GLP-1 secreted from alpha cells.


Assuntos
Compostos Benzidrílicos/farmacologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Endócrinas/efeitos dos fármacos , Células Secretoras de Glucagon/efeitos dos fármacos , Glucosídeos/farmacologia , Regeneração/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peptídeo C/metabolismo , Modelos Animais de Doenças , Células Endócrinas/metabolismo , Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células Secretoras de Glucagon/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Pró-Proteína Convertase 1/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose
4.
Nat Med ; 26(6): 964-973, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32528151

RESUMO

Metabolic responses to food influence risk of cardiometabolic disease, but large-scale high-resolution studies are lacking. We recruited n = 1,002 twins and unrelated healthy adults in the United Kingdom to the PREDICT 1 study and assessed postprandial metabolic responses in a clinical setting and at home. We observed large inter-individual variability (as measured by the population coefficient of variation (s.d./mean, %)) in postprandial responses of blood triglyceride (103%), glucose (68%) and insulin (59%) following identical meals. Person-specific factors, such as gut microbiome, had a greater influence (7.1% of variance) than did meal macronutrients (3.6%) for postprandial lipemia, but not for postprandial glycemia (6.0% and 15.4%, respectively); genetic variants had a modest impact on predictions (9.5% for glucose, 0.8% for triglyceride, 0.2% for C-peptide). Findings were independently validated in a US cohort (n = 100 people). We developed a machine-learning model that predicted both triglyceride (r = 0.47) and glycemic (r = 0.77) responses to food intake. These findings may be informative for developing personalized diet strategies. The ClinicalTrials.gov registration identifier is NCT03479866.


Assuntos
Glicemia/metabolismo , Microbioma Gastrointestinal , Insulina/metabolismo , Nutrientes , Período Pós-Prandial , Triglicerídeos/metabolismo , Adolescente , Adulto , Idoso , Peptídeo C/metabolismo , Carboidratos da Dieta , Gorduras na Dieta , Fibras na Dieta , Proteínas na Dieta , Feminino , Variação Genética , Teste de Tolerância a Glucose , Voluntários Saudáveis , Humanos , Individualidade , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Medicina de Precisão , Adulto Jovem
5.
Nutr Metab Cardiovasc Dis ; 30(7): 1216-1226, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32482454

RESUMO

BACKGROUND AND AIMS: Successful islet transplantation as a promising treatment of diabetes type 1 is threatened with the loss of islets during the pre-transplant culture due to hypoxia and oxidative stress-induced apoptosis. Therefore, optimization of culture in order to preserve the islets is a critical point. In this study, we investigated the effect of resveratrol, as a cytoprotective agent, on the cultured human islets. METHODS AND RESULTS: Isolated islets were treated with different concentrations of resveratrol for 24 and 72 h. Islets' viability, apoptosis, apoptosis markers, and insulin and C-peptide secretion, along with the production of reactive oxygen species (ROS), hypoxia inducible factor 1 alpha (HIF-1α), and its target genes in the islets were investigated. Our findings showed that the islets were exposed to hypoxia and oxidative stress after isolation and during culture. This insult induced apoptosis and decreased viability during 72 h. The presence of resveratrol significantly attenuated HIF-1α and ROS production, reduced apoptosis, promoted the VEGF secretion, and increased the insulin and C-peptide secretion. In this regard, resveratrol improved the islet's survival and function in the culture period. CONCLUSIONS: Using resveratrol can attenuate the stressful condition for the islets in the pre-transplant culture and subsequently ameliorate their viability and functionality that lead to successful outcome after clinical transplantation.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Adulto , Idoso , Peptídeo C/metabolismo , Hipóxia Celular , Sobrevivência Celular/efeitos dos fármacos , Citoproteção , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Técnicas de Cultura de Tecidos , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Transplant Proc ; 52(3): 987-991, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32143871

RESUMO

BACKGROUND: We assessed whether allograft rejection or failure can be predicted by an acute increase in C-peptide production from the transplanted pancreas. METHODS: Patients with a minimum of 5 years of follow-up post simultaneous pancreas-kidney transplant were identified. C-peptide levels were obtained during clinic visits routinely. Graft failure was defined as return to dependence on insulin therapy or return to dialysis for pancreas and kidney grafts, respectively. Protocol kidney allograft biopsies were performed at 3 and 12 months. For-cause biopsies were also performed. RESULTS: Acute rejections were detected in 11 patients on biopsy results of the renal allograft. C-peptide levels drawn prior to documented rejections were significantly higher in patients with acute rejection than patients with borderline or no rejection (P = .006). Receiver operating characteristics curves for C-peptide indicated greater accuracy in predicting rejection than simultaneously drawn serum creatinine or lipase. CONCLUSIONS: Higher C-peptide levels in simultaneous pancreas-kidney recipients is associated with acute rejection vs nonrejection.


Assuntos
Biomarcadores/sangue , Peptídeo C/metabolismo , Rejeição de Enxerto/sangue , Transplante de Rim , Transplante de Pâncreas , Adulto , Peptídeo C/análise , Feminino , Rejeição de Enxerto/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Homólogo
7.
Am J Physiol Endocrinol Metab ; 318(6): E956-E964, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182123

RESUMO

Enhanced meal-related enteroendocrine secretion, particularly of glucagon-like peptide-1 (GLP-1), contributes to weight-loss and improved glycemia after Roux-en-Y gastric bypass (RYGB). Dietary glucose drives GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) secretion postoperatively. Understanding how glucose triggers incretin secretion following RYGB could lead to new treatments of diabetes and obesity. In vitro, incretin release depends on glucose absorption via sodium-glucose cotransporter 1 (SGLT1). We investigated the importance of SGLT1/SGLT2 for enteropancreatic hormone concentrations and glucose metabolism after RYGB in a randomized, controlled, crossover study. Ten RYGB-operated patients ingested 50 g of oral glucose with and without acute pretreatment with 600 mg of the SGLT1/SGLT2-inhibitor canagliflozin. Paracetamol and 3-O-methyl-d-glucopyranose (3-OMG) were added to the glucose drink to evaluate rates of intestinal entry and absorption of glucose, respectively. Blood samples were collected for 4 h. The primary outcome was 4-h plasma GLP-1 (incremental area-under the curve, iAUC). Secondary outcomes included glucose, GIP, insulin, and glucagon. Canagliflozin delayed glucose absorption (time-to-peak 3-OMG: 50 vs. 132 min, P < 0.01) but did not reduce iAUC GLP-1 (6,067 vs. 7,273·min·pmol-1·L-1, P = 0.23), although peak GLP-1 concentrations were lowered (-28%, P = 0.03). Canagliflozin reduced GIP (iAUC -28%, P = 0.01; peak concentrations -57%, P < 0.01), insulin, and glucose excursions, whereas plasma glucagon (AUC 3,216 vs. 4,160 min·pmol·L-1, P = 0.02) and amino acids were increased. In conclusion, acute SGLT1/SGLT2-inhibition during glucose ingestion did not reduce 4-h plasma GLP-1 responses in RYGB-patients but attenuated the early rise in GLP-1, GIP, and insulin, whereas late glucagon concentrations were increased. The results suggest that SGLT1-mediated glucose absorption contributes to incretin hormone secretion after RYGB.


Assuntos
Canagliflozina/farmacologia , Derivação Gástrica , Polipeptídeo Inibidor Gástrico/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Transportador 1 de Glucose-Sódio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Transportador 2 de Glucose-Sódio/metabolismo , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Peptídeo C/efeitos dos fármacos , Peptídeo C/metabolismo , Estudos Cross-Over , Polipeptídeo Inibidor Gástrico/efeitos dos fármacos , Glucagon/efeitos dos fármacos , Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/efeitos dos fármacos , Teste de Tolerância a Glucose , Humanos , Incretinas/metabolismo , Insulina/metabolismo , Pessoa de Meia-Idade , Polipeptídeo Pancreático/efeitos dos fármacos , Polipeptídeo Pancreático/metabolismo , Transportador 1 de Glucose-Sódio/antagonistas & inibidores
8.
Life Sci ; 247: 117458, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32092333

RESUMO

AIMS: The use of natural agents with anti-diabetic effect in combination therapy adds further positive clinical implications in the management of diabetes mellitus. Interestingly, quercetin is one of the most potent naturally occurring antioxidant which possesses various pharmacological actions including anti-diabetic effect. Thus, this research was conducted to assess the efficiency of a new combination from gliclazide and quercetin on glycemic control as well as pancreatic islets and beta cells in STZ-experimental model of diabetes. MAIN METHODS: Diabetes has been induced by a single intraperitoneal injection of streptozotocin (STZ; 45 mg/kg) in adult male Wistar rats. For 3 consecutive weeks, diabetic rats were given orally either gliclazide (10 mg/kg), quercetin (50 mg/kg), or their combination. At the end of the experiment, histological, immunohistochemical and morphometrical examination of pancreatic tissues was performed. Furthermore, the changes in glucose metabolism, lipid profile, oxidative and inflammatory status were evaluated. KEY FINDINGS: Treatment with gliclazide alone decreased serum glucose, total cholesterol, triglycerides, malondialdehyde, tumor necrosis factor-alpha and nuclear factor kappa-Beta while increased serum C-peptide, superoxide dismutase, reduced glutathione and adiponectin levels. Combined administration of quercetin with gliclazide markedly augmented serum superoxide dismutase and reduced glutathione more than gliclazide alone and normalized all the above-mentioned parameters. Besides, this combination therapy restored immunostaining intensity, number of pancreatic islets and beta cells along with its area and perimeter. SIGNIFICANCE: Based on the aforementioned results, this combination could be considered a promising one in diabetes mellitus management.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Gliclazida/uso terapêutico , Hipoglicemiantes/uso terapêutico , Quercetina/uso terapêutico , Estreptozocina/metabolismo , Animais , Glicemia/metabolismo , Peptídeo C/metabolismo , Colesterol/metabolismo , Quimioterapia Combinada/métodos , Glutationa/metabolismo , Inflamação/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Malondialdeído/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Triglicerídeos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Expert Opin Investig Drugs ; 29(3): 221-236, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32031422

RESUMO

Introduction: Type 1 diabetes (T1D) is an autoimmune disease that results from the destruction of insulin-producing beta cells in the pancreas; it leads to the under or nonproduction of insulin. T1D is associated with numerous life-threatening micro- and macro-vascular complications and early deaths, hence the development of preventative strategies is a priority for research.Areas covered: The authors outline the drawbacks of available treatments for T1D and assess the three key strategies for prevention, including immunomodulatory therapies which hold the most potential. This article examines CTLA4-Ig and its efficacy and safety profiles. Finally, the pharmacokinetic parameters and pharmacodynamic markers of abatacept are shown in vivo and in clinical trials, guiding dosage regimen recommendations for future investigational studies.Expert opinion: Immunomodulation is one of the promising strategies for decelerating the progression of beta-cell destruction after the onset of T1D. It holds the advantage of specific immune modulation without systemic general immunosuppression. Preclinical and clinical studies have yielded promising data on the use of CTLA4-Ig in T1D. Variations in response to CTLA4-Ig might be partially explained by the existence of multiple T1D subtypes with varying baseline innate inflammatory/regulatory bias and the rate of C-peptide decline.


Assuntos
Abatacepte/administração & dosagem , Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunossupressores/administração & dosagem , Abatacepte/efeitos adversos , Abatacepte/farmacologia , Animais , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Progressão da Doença , Relação Dose-Resposta a Droga , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/farmacologia
10.
Transplantation ; 104(6): e144-e150, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32080160

RESUMO

BACKGROUND: Current histological methods cannot accurately determine the survival rate of human pancreatic islets following portal vein infusion. This is due, in part, to the low number of infused islets relative to the whole liver. In this study, we assessed the ability of confocal laser scanning microscopy (CLSM) to track human islets posttransplantation. METHODS: Immunodeficient mice were transplanted with human islets. Following engraftment, animals were euthanized, livers procured, and human islet ß cells immunofluorescently labeled with an insulin-specific antibody and evaluated by CLSM. A calibration curve comparing the area of insulin + hepatic islet ß cells to the number of human islets collected was developed. Levels of human C-peptide were measured in transplant recipients to determine islet function. RESULTS: The short-term survival rate of islet transplants was defined as y = 0.0422x + 2.7008, in which x is human islet number and y is liver islet ß cell area. Employing CLSM, human islets were detected in immunofluorescent labeled murine liver tissue sections posttransplantation. The ß cell-relative area of human islets in 500 islet equivalent (IEQ) specimens was 20.21 ± 1.16 mm and in 1000 IEQ specimens 39.4 ± 2.23 mm posttransplantation. Human islet posttransplant survival rates were 82.9 ± 5.50% (500 IEQ group) and 86.9 ± 5.28% (1000 IEQ group). CONCLUSIONS: These data indicate that CLSM can be employed to quantify and characterize pancreatic human islets after transplantation to murine livers.


Assuntos
Rejeição de Enxerto/diagnóstico , Microscopia Intravital/métodos , Transplante das Ilhotas Pancreáticas/efeitos adversos , Ilhotas Pancreáticas/diagnóstico por imagem , Microscopia Confocal/métodos , Animais , Peptídeo C/análise , Peptídeo C/metabolismo , Estudos de Viabilidade , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Modelos Animais , Transplante Heterólogo
11.
Biomed Res Int ; 2020: 7103053, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32051828

RESUMO

Mesenchymal stem cells (MSCs) can be differentiated in vitro to form insulin-producing cells (IPCs). However, the proportion of induced cells is modest. Extracts from injured pancreata of rodents promoted this differentiation, and three upregulated proteins were identified in these extracts. The aim of this study was to evaluate the potential benefits of adding these proteins to the differentiation medium alone or in combination. Our results indicate that the proportion of IPCs among the protein(s)-supplemented samples was significantly higher than that in the samples with no added proteins. The yield from samples supplemented with PRDX6 alone was 4-fold higher than that from samples without added protein. These findings were also supported by the results of fluorophotometry. Gene expression profiles revealed higher levels among protein-supplemented samples. Significantly higher levels of GGT, SST, Glut-2, and MafB expression were noted among PRDX6-treated samples. There was a stepwise increase in the release of insulin and c-peptide, as a function of increasing glucose concentrations, indicating that the differentiated cells were glucose sensitive and insulin responsive. PRDX6 exerts its beneficial effects as a result of its biological antioxidant properties. Considering its ease of use as a single protein, PRDX6 is now routinely used in our differentiation protocols.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Insulina/biossíntese , Células-Tronco Mesenquimais/metabolismo , Peroxirredoxina VI/metabolismo , Peroxirredoxina VI/farmacologia , Peptídeo C/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Humanos , Fator de Transcrição MafB/metabolismo , Peroxirredoxina VI/genética , Somatostatina/metabolismo , Transcriptoma , gama-Glutamiltransferase/metabolismo
12.
Am J Cardiol ; 125(5): 678-684, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31948661

RESUMO

Insulin resistance early after acute myocardial infarction is associated with increased heart failure and mortality. OMEGA-REMODEL was a prospective double-blind 1:1 randomized control trial of patients with AMI. We reported that 6-month treatment with omega-3 fatty acid (O-3FA) 4 g/day attenuated cardiac remodeling accompanied by reduction in inflammation. We hypothesized that insulin resistance modifies the therapeutic effect of O-3FA on post-MI cardiac remodeling. The OMEGA-REMODEL study group was dichotomized according to cohort- and gender-specific median cutoff value of leptin-to-adiponectin ratio (LAR) at baseline (LAR-Hi vs LAR-Lo). Mixed model regression analyses were used to evaluate effect modification of O-3FA on reduction of left ventricular end-systolic volume index (LVESVI) by LAR status. Baseline LAR was evaluated on 325 patients (59 ± 11 years, 81% male). A total of 168 patients were categorized in LAR-Lo, and 157 in LAR-Hi. O-3FA treatment resulted in significant LVESVI reduction in patients with LAR-Lo but not with LAR-Hi (p = 0.0002 vs 0.66, respectively). Mixed model regression analysis showed significant modification of LAR on O-3FA's treatment effect in attenuating LVESVI (p = 0.021). In conclusion, this post-hoc efficacy analysis suggests that LAR status significantly modified O-3FA's treatment effect in attenuating cardiac remodeling. During the convalescent phase of acute infarct healing, patients with lower insulin resistance estimated by LAR appear to derive more therapeutic response from O-3FA toward improvement of LVESVI.


Assuntos
Adiponectina/metabolismo , Ácidos Graxos Ômega-3/uso terapêutico , Resistência à Insulina , Leptina/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Remodelação Ventricular , Idoso , Peptídeo C/metabolismo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/metabolismo , Prognóstico , Proinsulina/metabolismo , Volume Sistólico , Resultado do Tratamento
13.
Diabetes Res Clin Pract ; 160: 107993, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31877344

RESUMO

AIM: To study the incidence of glucose intolerance in CP patients without diabetes by performing oral glucose tolerance test (OGTT). METHODS: We screened consecutive Indian CP patients without diabetes over 6 months by performing OGTT and correlated with physical characteristics and glycated hemoglobin (HbA1c). We also compared c-peptide and pancreatic polypeptide response in different groups based on OGTT. Relevant statistical tests were performed. P < 0.05 was considered significant. RESULTS: Total of 171 patients were screened. Mean duration of CP was 5.03 ± 4.32 years. 55 were detected to have prediabetes and 40 DM on OGTT. CP patients with diabetes and prediabetes had significantly dilated pancreatic duct compared to non-diabetic CP (4.2 ± 2.7 mm, 3.6 ± 2.7 mm, 2.84 ± 2.25 mm; p = 0.018). Fasting blood glucose (FBS) and 2-hour OGTT were 109.35 ± 19.06, 97.47 ± 11.94, 85.24 ± 9.95 and 236.13 ± 31.42, 154.65 ± 19.53, 112.89 ± 16.32 in patients with DM, prediabetes and CP patients without diabetes (p < 0.0001). There was a good c-peptide response (p = 0.001) and reduced pancreatic polypeptide response (p = 0.003) in CP patients compared to controls. CONCLUSION: Early in the course of disease reduced pancreatic polypeptide response in the presence of good c-peptide response may result in development of DM.


Assuntos
Glicemia/metabolismo , Peptídeo C/metabolismo , Intolerância à Glucose/sangue , Pancreatite Crônica/complicações , Adulto , Feminino , Humanos , Masculino , Pancreatite Crônica/sangue
14.
Endocr J ; 67(1): 95-98, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31597815

RESUMO

A 59-year-old woman unaware of having diabetes was transferred due to coma. Upon discovery at home, her consciousness on the Glasgow Coma Scale was E1V2M4, BP 95/84 mmHg, body temperature 34.7°C. On arrival at ER, height was 1.63 m, weight 97 kg, plasma glucose (PG) 1,897 mg/dL, HbA1c 13.6%, osmolality 421 mosm/kg, arterial pH 7.185, lactate 6.34 mmol/L, ß-hydroxybutyrate 7.93 mmol/L. With saline and regular insulin infusion, PG was lowered to 1,440 mg/dL at 2 hours and then to 250 mg/dL by Day 3, and consciousness normalized by Day 5. On admission, serum immunoreactive insulin (IRI) was undetectable (<0.03 U/mL), C-peptide immunoreactivity (CPR) undetectable (<0.003 ng/mL), and anti-glutamic acid decarboxylase antibody negative. Following the above-described treatment, fasting PG was 186 mg/dL and CPR 1.94 ng/mL, respectively, on Day 14; 2-h post-breakfast PG 239 mg/dL and CPR 6.28 ng/mL, respectively, on Day 18. The patient discharged on Day 18 with 1,800 kcal diet, 32 U insulin glargine and 40 mg gliclazide. Fifteen months later at outpatient clinic, her HbA1c was 6.9% and 2-h post-breakfast PG 123 mg/dL and CPR 5.30 ng/dL with 750 mg metformin, 10 mg gliclazide and 18 U insulin glargine. Transient, but total cessation of insulin secretion was documented in a patient with type 2 diabetes under severe metabolic decompensation. Swift, sustained recovery of insulin release indicated that lack of insulin at the time of emergency was due to secretory failure, i.e., unresponsive exocytotic machinery or depletion of releasable insulin, rather than loss of beta cells.


Assuntos
Peptídeo C/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Coma Diabético/metabolismo , Insulina/metabolismo , Acidose Láctica/complicações , Acidose Láctica/metabolismo , Acidose Láctica/terapia , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Coma Diabético/etiologia , Coma Diabético/terapia , Feminino , Hidratação , Hemoglobina A Glicada/metabolismo , Humanos , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Hiperglicemia/terapia , Hipoglicemiantes/uso terapêutico , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Cetose/complicações , Cetose/metabolismo , Cetose/terapia , Pessoa de Meia-Idade , Pancreatite/etiologia , Pancreatite/metabolismo
15.
J Diabetes Investig ; 11(1): 80-87, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31240874

RESUMO

AIMS/INTRODUCTION: The relationship between pancreatic fatty infiltration and diabetes is widely known, whereas the causal relationship is not clear. Furthermore, it is uncertain whether pathogenesis of pancreatic fat is similar to that of liver fat. We aimed to clarify the contribution of this type of fat to glucose metabolism in type 2 diabetes patients by cross-sectional and longitudinal analyses. MATERIAL AND METHODS: A total of 56 patients with type 2 diabetes who had been hospitalized twice were analyzed. We evaluated the mean computed tomography values of the pancreas (P), liver (L) and spleen (S). Lower computed tomography values indicate a greater fat content. We defined indices of pancreatic or liver fat content as the differences between P or L and S. We assessed the associations among fat content for the two organs (P-S, L-S) and clinical parameters at the first hospitalization, and then analyzed the associations between these fat contents and changes in glycometabolic markers (the second data values minus the first). RESULTS: In the cross-sectional study, P-S negatively correlated with the increment of C-peptide in the glucagon stimulation test (r = -0.71, P < 0.0001) and body mass index (r = -0.28, P = 0.034). L-S negatively correlated with homeostasis model assessment of insulin resistance (r = -0.73, P < 0.0001), body mass index (r = -0.62, P < 0.0001) and some other obesity-related indicators, but not with the increment of C-peptide in the glucagon stimulation test. In the longitudinal study, P-S positively correlated with the change of the increment of C-peptide in the glucagon stimulation test (r = 0.49, P = 0.021). CONCLUSIONS: In type 2 diabetes patients, pancreatic fat was less associated with obesity-related indicators than liver fat, but was more strongly associated with the longitudinal decrease in endogenous insulin-secreting capacity.


Assuntos
Tecido Adiposo/fisiopatologia , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 2/patologia , Fígado Gorduroso/fisiopatologia , Glucagon/farmacologia , Pancreatopatias/fisiopatologia , Idoso , Biomarcadores/análise , Estudos Transversais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Seguimentos , Fármacos Gastrointestinais/farmacologia , Teste de Tolerância a Glucose , Humanos , Estudos Longitudinais , Masculino , Prognóstico
16.
J Diabetes Investig ; 11(1): 75-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31222973

RESUMO

AIMS/INTRODUCTION: We investigated associations between glucose tolerance and ß-cell function using a series of estimation methods in a population-based study. MATERIALS AND METHODS: Data from the Dynamics of Lifestyle and Neighborhood Community on Health Study were analyzed. A total of 489 participants (263 women) were divided into three groups: normal glucose tolerance (NGT), prediabetes (PDM) and diabetes group. We estimated ß-cell function by the homeostasis model assessment of ß-cell function, proinsulin level (PI), C-peptide index, proinsulin-to-C-peptide ratio (PI/CPR) and proinsulin-to-insulin ratio. Because data on all five parameters of ß-cell function showed skewed distributions, the values of these parameters were normalized by natural logarithmic (ln) transformation. Next, the association between glucose tolerance and ß-cell function among participants without diabetes was examined. In this analysis, glucose tolerance was assessed based on glycated hemoglobin levels. RESULTS: In the crude analysis, ln(PI) and ln(PI/CPR) were significantly higher in the diabetes group than those in the PDM and NGT groups, and these parameters were significantly higher in the PDM group than in the NGT group. Only ln(PI) in the PDM group was significantly higher compared with that in the NGT group after adjustment for age, sex and body mass index (ln[PI]: PDM group 2.38 pmol/L, 95% confidence interval 2.29-2.47 pmol/L; NGT group 2.17 pmol/L, 95% confidence interval 2.12-2.22 pmol/L; P < 0.05). In addition, ln(PI) levels were significantly and positively correlated with glycated hemoglobin quartile in participants without diabetes. CONCLUSIONS: Our results showed that PI was the most sensitive to reflect glucose intolerance.


Assuntos
Biomarcadores/metabolismo , Glicemia/análise , Peptídeo C/metabolismo , Intolerância à Glucose/diagnóstico , Insulina/metabolismo , Proinsulina/metabolismo , Adulto , Idoso , Estudos Transversais , Feminino , Seguimentos , Intolerância à Glucose/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
17.
Acta Diabetol ; 57(2): 117-131, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31172294

RESUMO

AIMS: The possibility that verapamil has new beneficial effects in diabetic patients in terms of an improvement in glycometabolic control has been put forward recently in several studies. However, to date the issue is still under debate. We conducted the first systematic review examining the impact of verapamil-based treatment on glycometabolic outcomes, in type 2 diabetes (T2D) patients. METHODS: We searched the PubMed, MEDLINE, Embase, Cochrane and ClinicalTrials.gov up to 9 October 2018, for all studies evaluating whether verapamil-based treatment is associated with changes in glycated haemoglobin (HbA1c), fasting plasma glucose levels, glucose and C-peptide areas from baseline in humans, without restrictions for study type. RESULTS: Plasma glucose levels were lowered significantly by verapamil-based treatment in patients with T2D (mean change - 13 ± 5.29; P = 0.049); HbA1c values were instead not affected by the drug (mean change - 0.10 ± 0.12; P = 0.453). In five studies, groups exposed to verapamil achieved lower value of glycometabolic outcomes: comparison with values recorded in control groups showed a significant difference, in terms of both HbA1c and plasma glucose levels. CONCLUSIONS: Despite the fact that plasma glucose levels were lowered significantly by verapamil-based treatment in patients with T2D (the HbA1c values were not affected by the drug), the clinical significance of the glycometabolic response induced by verapamil-based treatment remains unclear due to the high variety of sample size and type of studies presently available. Further experimental and clinical trials are needed to clarify unambiguously the role of verapamil in metabolic control.


Assuntos
Linfócitos B/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Verapamil/administração & dosagem , Glicemia/metabolismo , Peptídeo C/metabolismo , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/complicações , Jejum/sangue , Feminino , Hemoglobina A Glicada/metabolismo , Humanos , Masculino
18.
Adv Clin Chem ; 93: 115-167, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31655729

RESUMO

The qualitative and quantitative determination of insulin and its related substances (e. g., C-peptide) is of great importance in many different areas of analytical chemistry. In particular, due to the steadily increasing prevalence of metabolic disorders such as diabetes mellitus, an adequate control of the circulating amount of insulin is desirable. In addition, also in forensics and doping control analysis, the determination of insulin in blood, urine or other biological matrices plays a major role. However, in order to establish general reference values for insulin and C-peptide for diabetology, the comparability of measured concentrations is indispensable. This has not yet been fully implemented, although enormous progress has been made in recent years, and the search for a "gold standard" method is still ongoing. In addition to established ligand-binding assays, an increasing number of mass-spectrometric methods have been developed and employed as the to-date available systems (for example, high-resolution/high accuracy mass spectrometers) provide the sensitivity required to determine analyte concentrations in the sub-ng/mL (sub-100pmol/L) level. Meanwhile, also high-throughput measurements have been realized to meet the requirement of testing a high number of samples in a short period of time. Further developments aim at enabling the online measurement of insulin in the blood with the help of an insulin sensor and, in the following, in addition to a brief review, today's state of the art testing developments are summarized.


Assuntos
Líquidos Corporais/metabolismo , Insulina/metabolismo , Sequência de Aminoácidos , Peptídeo C/metabolismo , Medicina Legal , Humanos , Insulina/sangue , Insulina/normas , Insulina/urina , Limite de Detecção , Espectrometria de Massas
19.
Stem Cell Reports ; 13(2): 307-321, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31378674

RESUMO

Generation of functional ß cells from pluripotent sources would accelerate diagnostic and therapeutic applications for diabetes research and therapy. However, it has been challenging to generate competent ß cells with dynamic insulin-secretory capacity to glucose and incretin stimulations. We introduced transcription factors, critical for ß-cell development and function, in differentiating human induced pluripotent stem cells (PSCs) and assessed the impact on the functionality of derived ß-cell (psBC) progeny. A perifusion system revealed stepwise transduction of the PDX1, NEUROG3, and MAFA triad (PNM) enabled in vitro generation of psBCs with glucose and GLP-1 responsiveness within 3 weeks. PNM transduction upregulated genes associated with glucose sensing, insulin secretion, and ß-cell maturation. In recipient diabetic mice, PNM-transduced psBCs showed glucose-responsive insulin secretion as early as 1 week post transplantation. Thus, enhanced pre-emptive ß-cell specification of PSCs by PNM drives generation of glucose- and incretin-responsive psBCs in vitro, offering a competent tissue-primed biotherapy.


Assuntos
Diabetes Mellitus Experimental/terapia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Glucose/farmacologia , Células-Tronco Pluripotentes Induzidas/transplante , Secreção de Insulina/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Peptídeo C/metabolismo , Diferenciação Celular , Diabetes Mellitus Experimental/induzido quimicamente , Regulação da Expressão Gênica , Teste de Tolerância a Glucose , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Fatores de Transcrição Maf Maior/genética , Fatores de Transcrição Maf Maior/metabolismo , Camundongos , Camundongos SCID , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Transativadores/genética , Transativadores/metabolismo , Transdução Genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
20.
Acta Diabetol ; 56(11): 1225-1230, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31367990

RESUMO

AIMS: To investigate the possibility of identifying a subtype of latent autoimmune diabetes in adults (LADA), T-LADA (T cell responses-positive and autoantibody-negative) from patients with phenotypic type 2 diabetes (T2D) by enzyme-linked immunospot (ELISPOT). METHODS: Eighty-two patients with phenotypic T2D were studied. Autoantibodies against glutamic acid decarboxylase (GAD), insulinoma-associated protein-2 and zinc transporter 8 were measured by radioligand assay. Thirty-nine Ab+ and 43 Ab- patients with phenotypic T2D were enrolled for T cell assay of responses to GAD65 and C-peptide antigen by ELISPOT. RESULTS: (1) Eleven of 43 Ab- participants with phenotypic T2D were demonstrated interferon (IFN)-γ secreting T cells by ELISPOT, while 13 of 39 Ab+ patients with phenotypic T2D were positive for T cells responses to islet antigens. (2) The onset ages of T cell+ people with phenotypic T2D were younger than that of T cell- individuals (42.7 ± 9.3 vs. 48.2 ± 10.2 years, P = 0.025). Moreover, T cell+ patients with T2D displayed a significantly lower fasting C-peptide (FCP) compared with T cell- participants [0.28 (0.02-0.84) vs. 0.42 (0.05-1.26) nmol/L, P = 0.013]. (3) Ab-T+ group had a significantly lower FCP compared with Ab-T- group [0.31 (0.13-0.84) vs. 0.51 (0.07-1.26) nmol/L, P = 0.023]. CONCLUSIONS: By measuring T cell responses to islet antigens in patients with phenotypic T2D, we identified a specific subtype of LADA who may be associated with worse basal ß-cell function than classic T2D (Ab-T-).


Assuntos
Diabetes Mellitus Tipo 2/imunologia , Diabetes Autoimune Latente em Adultos/imunologia , Fenótipo , Linfócitos T/imunologia , Adulto , Autoanticorpos/imunologia , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 2/sangue , Feminino , Glutamato Descarboxilase/imunologia , Humanos , Diabetes Autoimune Latente em Adultos/sangue , Diabetes Autoimune Latente em Adultos/classificação , Masculino , Pessoa de Meia-Idade , Transportador 8 de Zinco/imunologia
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