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1.
J Pathol ; 263(4-5): 429-441, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38837231

RESUMEN

The Ppy gene encodes pancreatic polypeptide (PP) secreted by PP- or γ-cells, which are a subtype of endocrine cells localised mainly in the islet periphery. For a detailed characterisation of PP cells, we aimed to establish PP cell lines. To this end, we generated a mouse model harbouring the SV40 large T antigen (TAg) in the Rosa26 locus, which is expressed upon Ppy-promoter-mediated Cre-loxP recombination. Whereas Insulin1-CreERT-mediated TAg expression in beta cells resulted in insulinoma, surprisingly, Ppy-Cre-mediated TAg expression resulted in the malignant transformation of Ppy-lineage cells. These mice showed distorted islet structural integrity at 5 days of age compared with normal islets. CK19+ duct-like lesions contiguous with the islets were observed at 2 weeks of age, and mice developed aggressive pancreatic ductal adenocarcinoma (PDAC) at 4 weeks of age, suggesting that PDAC can originate from the islet/endocrine pancreas. This was unexpected as PDAC is believed to originate from the exocrine pancreas. RNA-sequencing analysis of Ppy-lineage islet cells from 7-day-old TAg+ mice showed a downregulation and an upregulation of endocrine and exocrine genes, respectively, in addition to the upregulation of genes and pathways associated with PDAC. These results suggest that the expression of an oncogene in Ppy-lineage cells induces a switch from endocrine cell fate to PDAC. Our findings demonstrate that Ppy-lineage cells may be an origin of PDAC and may provide novel insights into the pathogenesis of pancreatic cancer, as well as possible therapeutic strategies. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Carcinoma Ductal Pancreático , Linaje de la Célula , Neoplasias Pancreáticas , Animales , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Ratones , Ratones Transgénicos , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Transformación Celular Neoplásica/metabolismo , Islotes Pancreáticos/patología , Islotes Pancreáticos/metabolismo , Antígenos Transformadores de Poliomavirus/genética , Antígenos Transformadores de Poliomavirus/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos
2.
Diabetologia ; 67(1): 156-169, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37870650

RESUMEN

AIMS/HYPOTHESIS: Glucagon-expressing pancreatic alpha cells have attracted much attention for their plasticity to transdifferentiate into insulin-producing beta cells; however, it remains unclear precisely when, and from where, alpha cells emerge and what regulates alpha cell fate. We therefore explored the spatial and transcriptional heterogeneity of alpha cell differentiation using a novel time-resolved reporter system. METHODS: We established the mouse model, 'Gcg-Timer', in which newly generated alpha cells can be distinguished from more-differentiated cells by their fluorescence. Fluorescence imaging and transcriptome analysis were performed with Gcg-Timer mice during the embryonic and postnatal stages. RESULTS: Fluorescence imaging and flow cytometry demonstrated that green fluorescence-dominant cells were present in Gcg-Timer mice at the embryonic and neonatal stages but not after 1 week of age, suggesting that alpha cell neogenesis occurs during embryogenesis and early neonatal stages under physiological conditions. Transcriptome analysis of Gcg-Timer embryos revealed that the mRNAs related to angiogenesis were enriched in newly generated alpha cells. Histological analysis revealed that some alpha cells arise close to the pancreatic ducts, whereas the others arise away from the ducts and adjacent to the blood vessels. Notably, when the glucagon signal was suppressed by genetic ablation or by chemicals, such as neutralising glucagon antibody, green-dominant cells emerged again in adult mice. CONCLUSIONS/INTERPRETATION: Novel time-resolved analysis with Gcg-Timer reporter mice uncovered spatiotemporal features of alpha cell neogenesis that will enhance our understanding of cellular identity and plasticity within the islets. DATA AVAILABILITY: Raw and processed RNA sequencing data for this study has been deposited in the Gene Expression Omnibus under accession number GSE229090.


Asunto(s)
Células Secretoras de Glucagón , Células Secretoras de Insulina , Islotes Pancreáticos , Ratones , Animales , Glucagón/metabolismo , Células Secretoras de Glucagón/metabolismo , Células Secretoras de Insulina/metabolismo , Diferenciación Celular/genética , Perfilación de la Expresión Génica , Islotes Pancreáticos/metabolismo
3.
Cancer Sci ; 115(2): 672-681, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38184804

RESUMEN

The Japan Diabetes Society and the Japan Cancer Association launched a joint committee and published their "First Joint Committee Report on Diabetes and Cancer" in 2013, compiling recommendations for physicians and health-care providers as well as for the general population. In 2016, the "Second Joint Committee Report on Diabetes and Cancer" summarized the current evidence on glycemic control and cancer risk in patients with diabetes. The current "Third Joint Committee Report on Diabetes and Cancer", for which the joint committee also enlisted the assistance of the Japanese Society of Clinical Oncology and the Japanese Society of Medical Oncology, reports on the results from the questionnaire survey, "Diabetes Management in Patients Receiving Cancer Therapy," which targeted oncologists responsible for cancer management and diabetologists in charge of glycemic control in cancer patients. The results of the current survey indicated that there is a general consensus among oncologists and diabetologists with regard to the need for guidelines on glycemic control goals, the relevance of glycemic control, and glycemic control during cancer therapy in cancer patients.


Asunto(s)
Diabetes Mellitus , Neoplasias , Oncólogos , Médicos , Humanos , Japón/epidemiología , Diabetes Mellitus/epidemiología , Neoplasias/epidemiología , Neoplasias/terapia , Encuestas y Cuestionarios
4.
Biochem Biophys Res Commun ; 712-713: 149960, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38640734

RESUMEN

An essential ketone body, ß-hydroxybutyrate (BOHB), plays various roles in physiological regulations via protein acylations such as lysine acetylation and ß-hydroxybutyrylation. Here, to understand how BOHB systemically regulates acylations from an overarching perspective, we administered a ketogenic diet to mice to increase BOHB concentration and examined acylations. We found that global acetylation and ß-hydroxybutyrylation dramatically increase in various organs except for the brains, where the increase was much smaller than in the other organs. Interestingly, we observe no increase in histone acetylation in the organs where significant global protein acetylation occurs despite a substantial rise in histone ß-hydroxybutyrylation. Finally, we compared the transcriptome data of the mice's liver after the ketogenic diet to the public databases, showing that upregulated genes are enriched in those related to histone ß-hydroxybutyrylation in starvation. Our data indicate that a ketogenic diet induces diverse patterns of acylations depending on organs and protein localizations, suggesting that different mechanisms regulate acylations and that the ketogenic diet is associated with starvation in terms of protein modifications.


Asunto(s)
Ácido 3-Hidroxibutírico , Dieta Cetogénica , Histonas , Ratones Endogámicos C57BL , Animales , Histonas/metabolismo , Ratones , Ácido 3-Hidroxibutírico/metabolismo , Masculino , Acilación , Hígado/metabolismo , Acetilación , Especificidad de Órganos , Proteínas/metabolismo , Proteínas/genética , Transcriptoma
5.
Diabetes Obes Metab ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38924336

RESUMEN

AIM: To explore differences in imeglimin response among type 2 diabetes (T2D) patient clusters using data-driven cluster analysis. METHODS: Data-driven cluster analysis (non-hierarchical k-means clustering) was performed on randomized, double-blind, imeglimin monotherapy and adjunctive (to insulin) therapy trials based on four baseline variables: (1) disease duration; (2) body mass index (BMI); (3) HbA1c; and (4a) homeostatic model assessment of ß-cell function (HOMA-ß) (monotherapy trials) or (4b) insulin total daily dose (adjunctive trial). RESULTS: Four clusters were identified with distinct clinical characteristics in both monotherapy (1-4) and adjunctive therapy (I-IV) trials; clusters 1 and I had lower values across all four indices versus the overall population, clusters 2 and II had a longer diabetes duration, cluster 3 had higher baseline BMI and HOMA-ß, and cluster III had higher baseline BMI and insulin total daily dose, while clusters 4 and IV had higher baseline HbA1c. Between-group differences in HbA1c change (95% confidence interval) and effect size (ES) at week 24 varied considerably by cluster (cluster 1: -0.82 [-1.00, -0.63], ES = 1.47; cluster 2: -0.64 [-0.89, -0.39], ES = 1.18; cluster 3: -0.86 [-1.38, -0.33], ES = 0.84; cluster 4: -1.27 [-1.73, -0.82], ES = 1.44). For imeglimin adjunctive therapy, HbA1c improvements were significant versus placebo at week 16, excluding cluster III (cluster I: -0.63 [-0.95, -0.31], ES = 0.88; cluster II: -0.66 [-1.02, -0.30], ES = 1.13; cluster III: -0.31 [-0.73, 0.11], ES = 0.46; cluster IV: -0.82 [-1.29, -0.35], ES = 0.99). CONCLUSIONS: Differences in imeglimin response were observed among T2D patient clusters. Patient stratification may help with selection of those most probable to respond to imeglimin.

6.
Cereb Cortex ; 33(23): 11225-11234, 2023 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-37757477

RESUMEN

Insulin resistance may lead to structural and functional abnormalities of the human brain. However, the mechanism by which insulin resistance impairs the brain remains elusive. In this study, we used two large neuroimaging databases to investigate the brain regions where insulin resistance was associated with the gray matter volume and to examine the resting-state functional connectivity between these brain regions and each hypothalamic nucleus. Insulin resistance was associated with reduced gray matter volume in the regions of the default-mode and limbic networks in the cerebral cortex in older adults. Resting-state functional connectivity was prominent between these networks and the paraventricular nucleus of the hypothalamus, a hypothalamic interface connecting functionally with the cerebral cortex. Furthermore, we found a significant correlation in these networks between insulin resistance-related gray matter volume reduction and network paraventricular nucleus of the hypothalamus resting-state functional connectivity. These results suggest that insulin resistance-related gray matter volume reduction in the default-mode and limbic networks emerged through metabolic homeostasis mechanisms in the hypothalamus.


Asunto(s)
Sustancia Gris , Resistencia a la Insulina , Humanos , Anciano , Sustancia Gris/diagnóstico por imagen , Red en Modo Predeterminado , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Corteza Cerebral
7.
Clin Exp Nephrol ; 28(6): 588-595, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38643286

RESUMEN

BACKGROUND: EMPA-KIDNEY assessed the effects of empagliflozin 10 mg once daily vs. placebo in 6609 patients with chronic kidney disease (CKD) at risk of progression, including 612 participants from Japan. METHODS: Eligibility required an estimated glomerular filtration rate (eGFR) of ≥ 20 < 45; or ≥ 45 < 90 ml/min/1.73m2 with a urinary albumin-to-creatinine ratio (uACR) of ≥ 200 mg/g. The primary outcome was a composite of kidney disease progression (end-stage kidney disease, a sustained eGFR decline to < 10 ml/min/1.73m2 or ≥ 40% from randomization, or renal death) or cardiovascular death. In post-hoc analyses, we explored the effects of empagliflozin in participants from Japan vs. non-Japan regions, including additional models assessing whether differences in treatment effects between these regions could result from differences in baseline characteristics. RESULTS: Japanese participants had higher levels of albuminuria and eGFR than those from non-Japan regions. During a median of 2.0 year follow-up, a primary outcome occurred in 432 patients (13.1%) in the empagliflozin group and in 558 patients (16.9%) in the placebo group (hazard ratio [HR], 0.72, 95% confidence interval [95%CI] 0.64-0.82; P < 0.0001). Among the participants from non-Japan regions, there were 399 vs. 494 primary outcomes (0.75, 0.66-0.86), and 33 vs. 64 (0.49, 0.32-0.75; heterogeneity p = 0.06) in Japan. Results were similar when models explicitly considered treatment interactions with diabetes status, categories of eGFR/uACR, and recruitment in Japan (heterogeneity p = 0.08). Safety outcomes were broadly comparable between the two groups, and by Japanese status. CONCLUSIONS: Empagliflozin safely reduced the risk of "kidney disease progression or cardiovascular death" in patients with CKD, with consistent effects in participants from Japan.


Asunto(s)
Albuminuria , Compuestos de Bencidrilo , Progresión de la Enfermedad , Tasa de Filtración Glomerular , Glucósidos , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Glucósidos/uso terapéutico , Glucósidos/efectos adversos , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/diagnóstico , Masculino , Compuestos de Bencidrilo/uso terapéutico , Compuestos de Bencidrilo/efectos adversos , Femenino , Persona de Mediana Edad , Tasa de Filtración Glomerular/efectos de los fármacos , Japón/epidemiología , Anciano , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Albuminuria/tratamiento farmacológico , Resultado del Tratamiento , Riñón/fisiopatología , Riñón/efectos de los fármacos , Método Doble Ciego , Fallo Renal Crónico/tratamiento farmacológico , Enfermedades Cardiovasculares
8.
Clin Exp Nephrol ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970650

RESUMEN

BACKGROUND: For the development of pharmaceutical products in kidney field, appropriate surrogate endpoints which can predict long-term prognosis are needed as an alternative to hard endpoints, such as end-stage kidney disease. Though international workshop has proposed estimated glomerular filtration rate (GFR) slope reduction of 0.5-1.0 mL/min/1.73 m /year and 30% decrease in albuminuria/proteinuria as surrogate endpoints in early and advanced chronic kidney disease (CKD), it was not clear whether these are applicable to Japanese patients. METHODS: We analyzed J-CKD-DB and CKD-JAC, Japanese databases/cohorts of CKD patients, and J-DREAMS, a Japanese database of patients with diabetes mellitus to investigate the applicability of eGFR slope and albuminuria/proteinuria to the Japanese population. Systematic review on those endpoints was also conducted including the results of clinical trials published after the above proposal. RESULTS: Our analysis showed an association between eGFR slope and the risk of end-stage kidney disease. A 30% decrease in albuminuria/proteinuria over 2 years corresponded to a 20% decrease in the risk of end-stage kidney disease patients with baseline UACR ≥ 30 mg/gCre or UPCR ≥ 0.15 g/gCre in the analysis of CKD-JAC, though this analysis was not performed on the other database/cohort. Those results suggested similar trends to those of the systematic review. CONCLUSION: The results suggested that eGFR slope and decreased albuminuria/proteinuria may be used as a surrogate endpoint in clinical trials for early CKD (including diabetic kidney disease) in Japanese population, though its validity and cutoff values must be carefully considered based on the latest evidence and other factors.

9.
BMC Geriatr ; 24(1): 614, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39026160

RESUMEN

BACKGROUND: With the aging of the population worldwide, extending healthy life expectancy is an urgent issue. Muscle mass has been reported to be associated with physical independence and longevity. This study aimed to investigate the characteristics of food intake in urban community-dwelling older adults with low muscle mass. METHODS: This cross-sectional study used baseline data from the Bunkyo Health Study, which included 1618 urban community-dwelling older adults aged 65-84 years. All participants underwent measurement of body composition using bioelectrical impedance analysis and evaluation of nutrient and food intake using the brief-type self-administered diet history questionnaire. Participants were stratified by sex and divided into robust or low skeletal muscle mass index (SMI) groups according to the Asian Working Group for Sarcopenia criteria to compare differences in nutrient and food intake. RESULTS: The mean age and body mass index were 73.1 ± 5.4 years and 22.6 ± 3.1 kg/m2, respectively. The prevalence of low SMI was 31.1% in men and 43.3% in women. In men, all food intake, including total energy intake, was similar between the low SMI group and the robust group. In women, the low SMI group had less total energy intake, and consumed lower amounts of energy-producing nutrients (protein, fat, and carbohydrates), but there were only small differences in the intake of specific foods. CONCLUSIONS: There were sex differences in food intake characteristics between urban community-dwelling older adults with low SMI and those who were robust. Advising women to increase their energy intake may be important in preventing muscle loss, and further research is needed in men.


Asunto(s)
Vida Independiente , Sarcopenia , Población Urbana , Humanos , Anciano , Masculino , Femenino , Estudios Transversales , Anciano de 80 o más Años , Vida Independiente/tendencias , Sarcopenia/epidemiología , Población Urbana/tendencias , Dieta , Japón/epidemiología , Composición Corporal/fisiología , Músculo Esquelético/fisiología , Ingestión de Alimentos/fisiología , Ingestión de Energía/fisiología
10.
Diabetologia ; 66(12): 2356-2367, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37750893

RESUMEN

AIMS/HYPOTHESIS: Previous studies have suggested that glucose variability may accelerate atherosclerosis progression in people with type 2 diabetes. Current guidelines recommend assessing glycaemic control using continuous glucose monitoring (CGM), which provides a comprehensive glycaemic profile to supplement HbA1c measurement. However, the association between CGM-derived metrics and atherosclerosis progression is not entirely clear. METHODS: This exploratory study used baseline data and data obtained after 104 weeks from an ongoing prospective, multicentre, observational study. Six hundred study participants with type 2 diabetes and no apparent history of symptomatic cardiovascular disease underwent CGM and ultrasonographic atherosclerosis measurements of the carotid arteries, including the intima-media thickness (IMT) and grey-scale median (GSM), at baseline and 104 weeks. Non-invasive ultrasonic tissue characterisation of the carotid artery wall or plaque using the GSM reflects vascular composition. Multivariate regression models were used to analyse the association between CGM-derived indices, mainly time in range (TIR) and CV, and changes in carotid atherosclerosis index values. RESULTS: Over the 104-week study period, there were modest increases in mean IMT (from 0.759±0.153 to 0.773±0.152 mm, p<0.001) and thickened-lesion GSM (from 43.5±19.5 to 53.9±23.5 units, p<0.001), but no significant changes in common carotid artery maximum-IMT (from 1.109±0.442 to 1.116±0.469 mm, p=0.453) or mean GSM (from 48.7±19.3 to 49.8±20.8 units, p=0.092). In a linear regression model with adjustment for possible atherosclerotic risk factors, including HbA1c, TIR and CV at baseline were significantly associated with the annual change in mean GSM (regression coefficient per 10% increase in TIR 0.52; 95% CI 0.06, 0.98; Hochberg-adjusted p value 0.038; regression coefficient per 1% increase in CV -0.12; 95% CI -0.22, -0.02; Hochberg-adjusted p value 0.038). TIR and CV at baseline were also significantly associated with the annual change in thickened-lesion GSM (regression coefficient per 10% increase in TIR 0.95; 95% CI 0.12, 1.79; Hochberg-adjusted p value 0.038; regression coefficient per 1% increase in CV -0.19; 95% CI -0.36, -0.01; Hochberg-adjusted p value 0.038). Participants who achieved target CGM-derived metrics at baseline, as proposed by an international consensus, showed significant annual changes in mean GSM compared with those who did not (0.94±6.88 vs -0.21±6.19 units/year, p=0.007). CONCLUSIONS/INTERPRETATION: TIR and CV were significantly associated with changes in the tissue characteristics of the carotid artery wall. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry, number UMIN000032325.


Asunto(s)
Aterosclerosis , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Grosor Intima-Media Carotídeo , Estudios Prospectivos , Glucemia , Automonitorización de la Glucosa Sanguínea , Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Común/diagnóstico por imagen
11.
Neurobiol Dis ; 177: 105990, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36621631

RESUMEN

OBJECTIVE: The glymphatic system is a glial-based perivascular network that promotes brain metabolic waste clearance. Reduced glymphatic flow has been observed in rat models of type 2 diabetes and hypertension, indicating the role of vascular risk factors in the glymphatic system. However, little is known about how vascular risk factors affect the human glymphatic system. The present study aims to assess the relationships between metabolic syndrome (MetS), a cluster of vascular risk factors, and the glymphatic system function using diffusion magnetic resonance imaging (MRI)-based measures of water diffusivity in the glymphatic compartments, including the brain interstitial space and perivascular spaces around the deep medullary vein. We hypothesized that vascular risk factors are associated with glymphatic dysfunction, leading to cognitive impairment in older adults. METHODS: This cross-sectional study assessed 61 older adults (age range, 65-82 years) who had participated in the Bunkyo Health Study, including 15 healthy controls (mean age, 70.87 ± 4.90 years) and 46 individuals with MetS (mean age, 71.76 ± 4.61 years). Fractional volume of extracellular-free water (FW) and an index of diffusion tensor imaging along the perivascular space (DTI-ALPS) were used as indirect indicators of water diffusivity in the interstitial extracellular and perivenous spaces of white matter, respectively. RESULTS: After adjusting for age, sex, years of education, total Fazekas scale, Pittsburgh sleep quality index (PSQI) score, and intracranial volume (ICV), a significantly (P = 0.030; Cohen's d = 1.01) higher FW was observed in individuals with MetS than in the healthy controls. Furthermore, individuals with MetS had a significantly (P = 0.031; Cohen's d = 0.86) lower ALPS index than the healthy controls, with age, sex, years of education, total Fazekas scale, PSQI score, ICV, fractional anisotropy, and mean diffusivity included as confounding factors. Higher FW was significantly associated with lower ALPS index (r = -0.37; P = 0.004). Multiple linear regression (MLR) with backward elimination analyses showed that higher diastolic blood pressure (BP; standardized ß = 0.33, P = 0.005) was independently associated with higher FW, whereas higher fasting plasma glucose levels (standardized ß = -0.63, P = 0.002) or higher Brinkman index of cigarette consumption cumulative amount (standardized ß = -0.27, P = 0.022) were associated with lower ALPS index. The lower ALPS index (standardized ß, 0.28; P = 0.040) was associated with poorer global cognitive performance, which was determined using the Japanese version of the Montreal Cognitive Assessment (MOCA-J) scores. Finally, partial correlation analyses showed a significant correlation between higher FW and lower MOCA-J scores (r = -0.35; P = 0.025) and between higher FW and higher diastolic BP (r = 0.32, P = 0.044). CONCLUSION: The present study shows the changes in diffusion MRI-based measures reflected by the higher FW and lower ALPS index in older adults with MetS, possibly due to the adverse effect of vascular risk factors on the glymphatic system. Our findings also indicate the associations between the diffusion MRI-based measures and elevated diastolic BP, hyperglycemia, smoking habit, and poorer cognitive performance. However, owing to the limitations of this study, the results should be cautiously interpreted.


Asunto(s)
Diabetes Mellitus Tipo 2 , Sistema Glinfático , Síndrome Metabólico , Humanos , Animales , Ratas , Anciano , Anciano de 80 o más Años , Sistema Glinfático/diagnóstico por imagen , Imagen de Difusión Tensora , Síndrome Metabólico/diagnóstico por imagen , Estudios Transversales , Neuroimagen , Agua
12.
Biochem Biophys Res Commun ; 676: 132-140, 2023 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-37516030

RESUMEN

Insulin is essential in controlling blood glucose levels, and its synthesis and secretion have been well investigated. In contrast, how insulin secretory granules (ISGs) are degraded in pancreatic beta cells remains largely unknown. To clarify the mechanism, we constructed a fluorescent reporter detecting ISG degradation, where EGFP and mCherry are tandemly conjugated to a cytoplasmic region of ZnT8, an ISG membrane-localized protein. Depletion of serum and amino acid stimulated lysosomal ISG degradation detected with the reporter. Next, with MIN6 cells expressing Cas9 and the reporter, we investigated the involvement of conventional Atg5/7-dependent autophagy to show that it is dispensable for the ISG degradation process. Finally, we performed genome-wide screening by enriching the cells lacking the ISG degradation and showed that pathways regulating autophagy are not identified. These results suggest that alternative degradation in lysosomes, instead of conventional autophagy, may be involved in ISG degradation.


Asunto(s)
Células Secretoras de Insulina , Insulina , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Secreción de Insulina , Proteínas de la Membrana/metabolismo , Colorantes/metabolismo , Vesículas Secretoras/metabolismo , Gránulos Citoplasmáticos/metabolismo
13.
Cardiovasc Diabetol ; 22(1): 143, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349722

RESUMEN

BACKGROUND: This study aimed to assess the long-term effects of tofogliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, on atherosclerosis progression and major clinical parameters in patients with type 2 diabetes lacking an apparent history of cardiovascular disease. METHODS: This was a prospective observational 2-year extension study of the "Using TOfogliflozin for Possible better Intervention against Atherosclerosis for type 2 diabetes patients (UTOPIA)" trial, a 2-year randomized intervention study. The primary endpoints represented changes in the carotid intima-media thickness (IMT). Secondary endpoints included brachial-ankle pulse wave velocity (baPWV) and biomarkers for glucose metabolism, lipid metabolism, renal function, and cardiovascular risks. RESULTS: The mean IMT of the common carotid artery (IMT-CCA) significantly decreased in both the tofogliflozin (- 0.067 mm, standard error 0.009, p < 0.001) and conventional treatment groups (- 0.080 mm, SE 0.009, p < 0.001) throughout the follow-up period; however, no significant intergroup differences in the changes (0.013 mm, 95% confidence interval (CI) - 0.012 to 0.037, p = 0.32) were observed in a mixed-effects model for repeated measures. baPWV significantly increased in the conventional treatment group (82.7 ± 210.3 cm/s, p = 0.008) but not in the tofogliflozin group (- 17.5 ± 221.3 cm/s, p = 0.54), resulting in a significant intergroup difference in changes (- 100.2 cm/s, 95% CI - 182.8 to - 17.5, p = 0.018). Compared to the conventional treatment group, tofogliflozin significantly improved the hemoglobin A1c and high-density lipoprotein cholesterol levels, body mass index, abdominal circumference, and systolic blood pressure. The frequencies of total and serious adverse events did not vary significantly between the groups. CONCLUSIONS: Tofogliflozin was not associated with improved inhibition of carotid wall thickening but exerted long-term positive effects on various cardiovascular risk factors and baPWV while showing a good safety profile.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Índice Tobillo Braquial , Grosor Intima-Media Carotídeo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Análisis de la Onda del Pulso , Utopias
14.
Exp Physiol ; 108(7): 940-945, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37074636

RESUMEN

NEW FINDINGS: What is the central question of this study? Ageing leads to a loss of mass in skeletal muscle, but the effect of obesity on ageing-related muscle wasting is unclear. In this study, we aimed to demonstrate the specific effect of obesity on fast-twitch skeletal muscle in ageing. What is the main finding and its importance? Our findings show that the obesity induced by long-term ingestion of a high-fat diet does not aggravate muscle wasting in fast-twitch skeletal muscle of aged mice, indicating that the present study provides morphological characteristics for skeletal muscle of sarcopenic obesity. ABSTRACT: Obesity and ageing reduce muscle mass and lead to deficits in muscle maintenance, but it is not known whether obesity accelerates muscle wasting additively in the setting of ageing. We investigated morphological characteristics in fast-twitch extensor digitorum longus (EDL) muscle of mice fed a low-fat diet (LFD) or a high-fat diet (HFD) for 4 or 20 months. The fast-twitch EDL muscle was harvested, and the muscle fibre-type composition, individual muscle cross-sectional area and myotube diameter were measured. We found an increase in the percentage of type IIa and IIx myosin heavy chain fibres in the whole EDL muscle, but a decrease in type IIB myosin heavy chain in both HFD protocols. The cross-sectional area and myofibre diameter were lower in both groups of aged mice (after 20 months of LFD or HFD) compared with young mice (after 4 months of the diets), but there were no differences between mice fed LFD or HFD for 20 months. These data suggest that long-term feeding of HFD does not aggravate muscle wasting in fast-twitch EDL muscle of male mice.


Asunto(s)
Fibras Musculares de Contracción Rápida , Fibras Musculares de Contracción Lenta , Ratones , Masculino , Animales , Dieta Alta en Grasa/efectos adversos , Cadenas Pesadas de Miosina , Músculo Esquelético/fisiología , Atrofia Muscular/etiología , Obesidad
15.
Nephrol Dial Transplant ; 38(5): 1204-1216, 2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-36002026

RESUMEN

BACKGROUND: Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease (ESKD), but currently available treatments do not improve kidney function or prevent the initiation of dialysis/kidney replacement therapy. A previous study demonstrated that bardoxolone methyl improves the estimated glomerular filtration rate (eGFR), but the study was prematurely terminated because of an imbalance in heart failure between treatment groups. The subsequent phase 2 TSUBAKI study demonstrated no incidence of heart failure and an improved eGFR and GFR as determined by inulin clearance in DKD patients. METHODS: This randomized, double-blind, placebo-controlled multicentre phase 3 study was designed to assess the efficacy and safety of bardoxolone methyl in DKD patients with an eGFR ≥15.0-<60.0 ml/min/1.73 m2 and a urinary albumin:creatinine ratio (UACR) ≤3500 mg/g but without risk factors for heart failure. The primary endpoint is the time to onset of a ≥30% decrease in the eGFR or ESKD. Randomized patients (1:1) have been under treatment with once-daily oral bardoxolone methyl (5, 10 or 15 mg by intrapatient dose adjustment) or placebo for at least 3 years. RESULTS: The mean age of the 1013 patients is 65.9 years, 21.5% are female, the mean eGFR is 37.84 ml/min/1.73 m2 and the median UACR is 351.80 mg/g. CONCLUSIONS: Appropriate patients are enrolled in this study. This study will investigate the long-term efficacy and safety of bardoxolone methyl in DKD patients covering a wider range of eGFR (≥15.0-<60.0 ml/min/1.73 m2) and albuminuria (≤3500 mg/g) compared with previous studies.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Insuficiencia Cardíaca , Fallo Renal Crónico , Insuficiencia Renal Crónica , Humanos , Femenino , Anciano , Masculino , Nefropatías Diabéticas/etiología , Diabetes Mellitus Tipo 2/complicaciones , Diálisis Renal/efectos adversos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/tratamiento farmacológico , Método Doble Ciego , Insuficiencia Cardíaca/complicaciones , Tasa de Filtración Glomerular , Albuminuria/etiología , Albuminuria/complicaciones
16.
Diabetes Obes Metab ; 25(7): 1890-1899, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36906837

RESUMEN

AIM: To identify distinct HbA1c trajectories in people with type 2 diabetes (T2D) starting second-line glucose-lowering therapy. MATERIALS AND METHODS: DISCOVER was a 3-year observational study of individuals with T2D beginning second-line glucose-lowering therapy. Data were collected at initiation of second-line treatment (baseline) and at 6, 12, 24 and 36 months. Latent class growth modelling was used to identify groups with distinct HbA1c trajectories. RESULTS: After exclusions, 9295 participants were assessed. Four distinct HbA1c trajectories were identified. Mean HbA1c levels decreased between baseline and 6 months in all groups; 72.4% of participants showed stable good levels of glycaemic control over the remainder of follow-up, 18.0% showed stable moderate levels of glycaemic control and 2.9% showed stable poor levels of glycaemic control. Only 6.7% of participants showed highly improved glycaemic control at month 6 and stable control over the rest of follow-up. For all groups, dual oral therapy use decreased over time, compensated for by the increasing use of other treatment regimens. Use of injectable agents increased over time in groups with moderate and poor glycaemic control. Logistic regression models suggested that participants from high-income countries were more probable to be in the stable good trajectory group. CONCLUSIONS: Most people receiving second-line glucose-lowering treatment in this global cohort achieved stable good or highly improved long-term glycaemic control. One-fifth of participants showed moderate or poor glycaemic control during follow-up. Further large-scale studies are required to characterize possible factors associated with patterns of glycaemic control to inform personalized diabetes treatment.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hiperglucemia , Humanos , Hipoglucemiantes/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada , Glucosa , Estudios Prospectivos , Glucemia , Hiperglucemia/prevención & control
17.
Diabetes Obes Metab ; 25(1): 46-55, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36111434

RESUMEN

AIMS: To describe glucose-lowering treatment regimens and glycated haemoglobin (HbA1c) trajectories in individuals with type 2 diabetes (T2D) over 36 months of follow-up from the start of second-line therapy. MATERIALS AND METHODS: This data analysis from the 3-year, observational DISCOVER study programme included 14 687 participants from 37 countries with T2D initiating second-line glucose-lowering therapy. Treatment and HbA1c data were collected at baseline (start of second-line therapy) and at 6, 12, 24 and 36 months. Treatment regimen changes over follow-up were analysed using the McNemar test, with carry-forward imputation for intermediate missing values. RESULTS: A total of 11 592 participants had treatment data at baseline and 36 months, and 11 882 had HbA1c data at baseline. At baseline and 36 months, respectively, rates of oral monotherapy use were 12.1% and 12.4% (P = 0.22), rates of dual oral therapy use were 63.4% and 47.6% (P < 0.0001), rates of ≥ triple oral therapy use were 17.5% and 25.4% (P < 0.0001), and rates of injectable treatment use were 7.0% and 13.7% (P < 0.0001). Use of injectable drugs was most common among participants with an HbA1c level ≥64 mmol/mol (≥8.0%). Overall, 42.9% of participants changed treatment during follow-up. Mean HbA1c levels at baseline and 6 months were 67 mmol/mol (8.3%) and 55 mmol/mol (7.2%), respectively, remaining stable thereafter. CONCLUSIONS: Dual oral therapy was the most common treatment regimen at the start of second-line treatment, and over half of the participants remained on the same treatment during follow-up.


Asunto(s)
Diabetes Mellitus Tipo 2 , Glucosa , Humanos , Hemoglobina Glucada , Diabetes Mellitus Tipo 2/tratamiento farmacológico
18.
Diabetologia ; 65(5): 811-828, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35243521

RESUMEN

AIMS/HYPOTHESIS: While pancreatic beta cells have been shown to originate from endocrine progenitors in ductal regions, it remains unclear precisely where beta cells emerge from and which transcripts define newborn beta cells. We therefore investigated characteristics of newborn beta cells extracted by a time-resolved reporter system. METHODS: We established a mouse model, 'Ins1-GFP; Timer', which provides spatial information during beta cell neogenesis with high temporal resolution. Single-cell RNA-sequencing (scRNA-seq) was performed on mouse beta cells sorted by fluorescent reporter to uncover transcriptomic profiles of newborn beta cells. scRNA-seq of human embryonic stem cell (hESC)-derived beta-like cells was also performed to compare newborn beta cell features between mouse and human. RESULTS: Fluorescence imaging of Ins1-GFP; Timer mouse pancreas successfully dissected newly generated beta cells as green fluorescence-dominant cells. This reporter system revealed that, as expected, some newborn beta cells arise close to the ducts (ßduct); unexpectedly, the others arise away from the ducts and adjacent to blood vessels (ßvessel). Single-cell transcriptomic analyses demonstrated five distinct populations among newborn beta cells, confirming spatial heterogeneity of beta cell neogenesis such as high probability of glucagon-positive ßduct, musculoaponeurotic fibrosarcoma oncogene family B (MafB)-positive ßduct and musculoaponeurotic fibrosarcoma oncogene family A (MafA)-positive ßvessel cells. Comparative analysis with scRNA-seq data of mouse newborn beta cells and hESC-derived beta-like cells uncovered transcriptional similarity between mouse and human beta cell neogenesis including microsomal glutathione S-transferase 1 (MGST1)- and synaptotagmin 13 (SYT13)-highly-expressing state. CONCLUSIONS/INTERPRETATION: The combination of time-resolved histological imaging with single-cell transcriptional mapping demonstrated novel features of spatial and transcriptional heterogeneity in beta cell neogenesis, which will lead to a better understanding of beta cell differentiation for future cell therapy. DATA AVAILABILITY: Raw and processed single-cell RNA-sequencing data for this study has been deposited in the Gene Expression Omnibus under accession number GSE155742.


Asunto(s)
Fibrosarcoma , Células Secretoras de Insulina , Transcriptoma , Animales , Diferenciación Celular/genética , Fibrosarcoma/metabolismo , Glucagón/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Ratones , Conductos Pancreáticos , ARN
19.
Biochem Biophys Res Commun ; 612: 99-104, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35512463

RESUMEN

Autophagy is known to play an essential role in intracellular quality control through the degradation of damaged organelles and components. We previously demonstrated that ß-cell-specific autophagy deficient mice, which lack Atg7, exhibited impaired glucose tolerance, accompanied by the accumulation of sequestosome 1/p62 (hereafter referred to as p62). Whereas p62 has been reported to play essential roles in regulating cellular homeostasis in the liver and adipose tissue, we previously showed that ß-cell-specific p62 deficiency does not cause any apparent impairment in glucose metabolism. In the present study, we investigated the roles of p62 in ß cells under autophagy-deficient conditions, by simultaneously inactivating both Atg7 and p62 in a ß-cell specific manner. Whereas p62 accumulation was substantially reduced in the islets of Atg7 and p62 double-deficient mice, glucose tolerance and insulin secretion were comparable to Atg7 single-deficient mice. Taken together, these findings suggest that the p62 accumulation appears to have little effect on ß-cell function under conditions of autophagy inhibition.


Asunto(s)
Células Secretoras de Insulina , Animales , Autofagia , Proteína 7 Relacionada con la Autofagia/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Ratones , Proteína Sequestosoma-1/genética , Proteína Sequestosoma-1/metabolismo
20.
Biochem Biophys Res Commun ; 611: 38-45, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35477091

RESUMEN

Autophagy is known to play a pivotal role in ß-cell function. While the lifelong inhibition of autophagy through Atg7 deletion in ß cells has been demonstrated to lead to impaired glucose tolerance together with ß-cell dysfunction, the temporal association between autophagy inhibition and ß-cell dysfunction remains unclear. To address such questions, inducible ß-cell-specific Atg7-knockout (ißAtg7KO) mice were generated, and autophagy inhibition was induced for two different time durations. Whereas 2 weeks of Atg7 ablation was sufficient to induce autophagy deficiency, confirmed by the accumulation of p62, ißAtg7KO mice exhibited normal glucose tolerance. In contrast, prolonged autophagy deficiency for 6 weeks resulted in glucose intolerance together with impaired insulin secretion. Direct mRNA sequencing and pathway analysis revealed that the gene set associated with insulin secretion was downregulated only after the 6-week prolonged autophagy inhibition. Furthermore, we identified a novel gene, Sprr1a, which was expressed at more than 50-fold higher levels during both the 2-week and 6-week autophagy inhibition. These findings suggest that autophagy insufficiency cumulatively leads to ß-cell failure after a certain interval, accompanied by stepwise alterations of gene expression patterns.


Asunto(s)
Intolerancia a la Glucosa , Células Secretoras de Insulina , Animales , Autofagia/fisiología , Proteína 7 Relacionada con la Autofagia/genética , Proteína 7 Relacionada con la Autofagia/metabolismo , Intolerancia a la Glucosa/genética , Intolerancia a la Glucosa/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Ratones , Ratones Noqueados
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