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1.
Diabetes Obes Metab ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267249

RESUMO

AIM: To elucidate the effects of ultra-processed foods (UPFs) on body weight and ad libitum energy intake compared with non-UPFs. MATERIALS AND METHODS: In this randomized, open-label crossover study conducted at the University of Tokyo Hospital, overweight/obese Japanese male participants were randomly assigned (1:1) to start the study with consumption of either UPFs or non-UPFs for 1 week, followed by a 2-week washout period, before crossing over to the alternate food diet for 1 week. Individuals with diabetes, hypertension or any other medical conditions who visited a hospital regularly were excluded. The meals were designed to be matched for the total energy and macronutrient levels. The primary outcome was the difference in the body weight change between the UPF and non-UPF periods. The differences in the average daily energy intake and chewing frequency were assessed as one of the prespecified secondary outcomes. RESULTS: Nine eligible participants were randomly assigned to start the study with either UPFs or non-UPFs. All participants completed the study. During the UPF period, participants gained 1.1 kg more weight (95% confidence interval 0.2 to 2.0; P = .021) and consumed 813.5 kcal more per day (342.4 to 1284.7; P = .0041) compared with during the non-UPF period. Regarding the chewing frequency, the number of chews per calorie was significantly lower during the UPF period (P = .016). CONCLUSIONS: Consumption of UPFs causes significant weight gain. Medical nutritional therapy focused on reducing the consumption of UPFs could be an effective strategy for preventing obesity.

2.
Endocr J ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39231651

RESUMO

The liver plays an important role in the control of glucose homeostasis. When insulin levels are low, such as in the fasting state, gluconeogenesis and glycogenolysis are stimulated to maintain the blood glucose levels. Conversely, in the presence of increased insulin levels, such as after a meal, synthesis of glycogen and lipid occurs to maintain the blood glucose levels within normal range. Insulin receptor signaling regulates glycogenesis, gluconeogenesis and lipogenesis through downstream pathways such as the insulin receptor substrate (IRS)-phosphoinositide 3 (PI3) kinase-Akt pathway. IRS-1 and IRS-2 are abundantly expressed in the liver and are thought to be responsible for transmitting the insulin signal from the insulin receptor to the intracellular effectors involved in the regulation of glucose and lipid homeostasis. Impaired insulin receptor signaling can cause hepatic insulin resistance and lead to type 2 diabetes. In the present study, we focus on a concept called "selective insulin resistance," which has received increasing attention recently: the frequent coexistence of hyperglycemia and hepatic steatosis in people with type 2 diabetes and obesity suggests that it is possible for the insulin signaling regulating gluconeogenesis to be impaired even while that regulating lipogenesis is preserved, suggestive of selective insulin resistance. In this review, we review the progress in research on the insulin actions and insulin signaling in the liver.

3.
Gastro Hep Adv ; 3(3): 426-439, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39131140

RESUMO

Background and Aims: Effective approaches for prevention of hepatocellular carcinoma (HCC) will have a significant impact on HCC-related mortality. There are strong preclinical data and rationale to support targeting epidermal growth factor receptor (EGFR) for HCC chemoprevention. Small molecule inhibitors of EGFR have been Food and Drug Administration-approved for cancer therapy, which provides an opportunity to repurpose one of these drugs for chemoprevention of HCC. Unfortunately, the frequency of side effects associated with administration of these drugs at oncology doses renders them ineffective for chemoprevention. This clinical trial assesses whether lower doses of one of these inhibitors, erlotinib, still engages EGFR in the liver to block signaling (eg, EGFR phosphorylation). The objective of this clinical trial was determination of a safe and minimum effective dose of erlorinib for which ≥ 50% reduction phospho-EGFR immunohistochemical staining in the liver was observed. Methods: Forty six participants were preregistered and 25 participants were registered in this multicenter trial. By dose de-escalation trial design, cohorts of participants received a 7-day course of erlotinib 75 mg/day, 50 mg/day or 25 mg/day with liver tissue acquisition prior to and after erlotinib. Results: A ≥50% reduction phospho-EGFR immunohistochemical staining in the liver was observed in a minimum of 40% of participants (predetermined threshhold) at each of the dose levels. Erlotinib was very well tolerated with few side effects observed, particularly at the dose of 25 mg/day. Favorable modulation of the Prognostic Liver Signature was observed in participants who received erlotinib. Conclusion: These data support the selection of erlotinib doses as low as 25 mg/day of for a longer intervention to assess for evidence of efficacy as an HCC chemoprevention drug (ClinicalTrials.govNCT02273362).

4.
Nat Commun ; 15(1): 7559, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39214995

RESUMO

In in situ capturing-based spatial transcriptomics, spots of the same size and printed at fixed locations cannot precisely capture the randomly-located single cells, therefore inherently failing to profile transcriptome at the single-cell level. To this end, we present STIE, an Expectation Maximization algorithm that aligns the spatial transcriptome to its matched histology image-based nuclear morphology and recovers missing cells from ~70% gap area, thereby achieving the real single-cell level and whole-slide scale deconvolution, convolution, and clustering for both low- and high-resolution spots. STIE characterizes cell-type-specific gene expression and demonstrates outperforming concordance with true cell-type-specific transcriptomic signatures than the other spot- and subspot-level methods. Furthermore, STIE reveals the single-cell level insights, for instance, lower actual spot resolution than its reported spot size, unbiased evaluation of cell type colocalization, superior power of high-resolution spot in distinguishing nuanced cell types, and spatial cell-cell interactions at the single-cell level other than spot level.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Análise de Célula Única , Transcriptoma , Análise de Célula Única/métodos , Perfilação da Expressão Gênica/métodos , Análise por Conglomerados , Animais , Humanos , Processamento de Imagem Assistida por Computador/métodos , Camundongos
5.
JCI Insight ; 9(18)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115943

RESUMO

Organelle stress exacerbates podocyte injury, contributing to perturbed lipid metabolism. Simultaneous organelle stresses can occur in the kidney in the diseased state; therefore, a thorough analysis of organelle communication is crucial for understanding the progression of kidney diseases. Although organelles closely interact with one another at membrane contact sites, limited studies have explored their involvement in kidney homeostasis. The endoplasmic reticulum (ER) protein, PDZ domain-containing 8 (PDZD8), is implicated in multiple-organelle-tethering processes and cellular lipid homeostasis. In this study, we aimed to elucidate the role of organelle communication in podocyte injury using podocyte-specific Pdzd8-knockout mice. Our findings demonstrated that Pdzd8 deletion exacerbated podocyte injury in an accelerated obesity-related kidney disease model. Proteomic analysis of isolated glomeruli revealed that Pdzd8 deletion exacerbated mitochondrial and endosomal dysfunction during podocyte lipotoxicity. Additionally, electron microscopy revealed the accumulation of abnormal, fatty endosomes in Pdzd8-deficient podocytes during obesity-related kidney diseases. Lipidomic analysis indicated that glucosylceramide accumulated in Pdzd8-deficient podocytes, owing to accelerated production and decelerated degradation. Thus, the organelle-tethering factor, PDZD8, plays a crucial role in maintaining mitochondrial and endosomal homeostasis during podocyte lipotoxicity. Collectively, our findings highlight the importance of organelle communication at the 3-way junction among the ER, mitochondria, and endosomes in preserving podocyte homeostasis.


Assuntos
Endossomos , Homeostase , Camundongos Knockout , Mitocôndrias , Podócitos , Podócitos/metabolismo , Podócitos/patologia , Animais , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Endossomos/metabolismo , Metabolismo dos Lipídeos , Obesidade/metabolismo , Obesidade/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Nefropatias/genética , Retículo Endoplasmático/metabolismo , Masculino
6.
Artigo em Inglês | MEDLINE | ID: mdl-39095229

RESUMO

The tumor suppressor p53 regulates metabolic homeostasis. Recently, Tsaousidou et al. reported that selective activation of p53 via downregulation of Tudor interacting repair regulator (TIRR) confers protection against cancer despite obesity and insulin resistance, providing new insights into the role of p53 at the intersection of oncogenesis and systemic metabolism.

7.
J Proteome Res ; 23(9): 3791-3805, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-38980715

RESUMO

Hepatocellular carcinoma (HCC) mortality rates continue to increase faster than those of other cancer types due to high heterogeneity, which limits diagnosis and treatment. Pathological and molecular subtyping have identified that HCC tumors with poor outcomes are characterized by intratumoral collagenous accumulation. However, the translational and post-translational regulation of tumor collagen, which is critical to the outcome, remains largely unknown. Here, we investigate the spatial extracellular proteome to understand the differences associated with HCC tumors defined by Hoshida transcriptomic subtypes of poor outcome (Subtype 1; S1; n = 12) and better outcome (Subtype 3; S3; n = 24) that show differential stroma-regulated pathways. Collagen-targeted mass spectrometry imaging (MSI) with the same-tissue reference libraries, built from untargeted and targeted LC-MS/MS was used to spatially define the extracellular microenvironment from clinically-characterized, formalin-fixed, paraffin-embedded tissue sections. Collagen α-1(I) chain domains for discoidin-domain receptor and integrin binding showed distinctive spatial distribution within the tumor microenvironment. Hydroxylated proline (HYP)-containing peptides from the triple helical regions of fibrillar collagens distinguished S1 from S3 tumors. Exploratory machine learning on multiple peptides extracted from the tumor regions could distinguish S1 and S3 tumors (with an area under the receiver operating curve of ≥0.98; 95% confidence intervals between 0.976 and 1.00; and accuracies above 94%). An overall finding was that the extracellular microenvironment has a high potential to predict clinically relevant outcomes in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteômica , Microambiente Tumoral , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/classificação , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/classificação , Humanos , Proteômica/métodos , Espectrometria de Massas em Tandem , Proteoma/análise , Proteoma/genética , Cromatografia Líquida , Aprendizado de Máquina , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética
8.
bioRxiv ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38895326

RESUMO

Alternative pre-mRNA splicing (AS) is a fundamental regulatory process that generates transcript diversity and cell type variation. We developed Shiba, a robust method integrating transcript assembly, splicing event identification, read counting, and statistical analysis, to efficiently quantify exon splicing levels across various types of RNA-seq datasets. Compared to existing pipelines, Shiba excels in capturing both annotated and unannotated or cryptic differential splicing events with superior accuracy, sensitivity, and reproducibility. Furthermore, Shiba's unique consideration of junction read imbalance and exon-body read coverage reduces false positives, essential for downstream functional analyses. We have further developed scShiba for single-cell/nucleus (sc/sn) RNA-seq data, enabling the exploration of splicing variations in heterogeneous cell populations. Both simulated and real data demonstrate Shiba's robustness across multiple sample sizes, including n=1 datasets and individual cell clusters from scRNA-seq. Application of Shiba on single replicates of RNA-seq identified new AS-NMD targets, and scShiba on snRNA-seq revealed intricate temporal AS regulation in dopaminergic neurons. Both Shiba and scShiba are provided in Docker/Singularity containers and Snakemake pipeline, enhancing accessibility and reproducibility. The comprehensive capabilities of Shiba and scShiba allow systematic and robust quantification of alternative splicing events, laying a solid foundation for mechanistic exploration of functional complexity in RNA splicing.

9.
Mol Cell ; 84(11): 2014-2016, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848690

RESUMO

In a recent publication in Science, Zocher et al.1 identify and characterize long-lived nuclear RNA in the mouse brain, suggesting their potential roles as guardians of neuronal longevity.


Assuntos
Neurônios , Animais , Neurônios/metabolismo , Camundongos , Longevidade/genética , Encéfalo/metabolismo , Humanos , RNA Nuclear/metabolismo , RNA Nuclear/genética
10.
Diabetes Ther ; 15(7): 1561-1575, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38753121

RESUMO

INTRODUCTION: Lifestyle management, including appropriate modifications of nutrition, exercise, and medication behaviors, is essential for optimal glycemic control. The absence of appropriate monitoring methods to validate the lifestyle change may hinder the modification and continuation of behaviors. In this study, we evaluated whether once-weekly glycated albumin (GA) measurement received via a smartphone application could improve glycemia management in patients with type 2 diabetes mellitus by supporting self-review and modification of lifestyle behaviors. METHODS: This open-label, randomized controlled, single-center study in Japan with an 8-week intervention period was conducted in individuals with type 2 diabetes mellitus and HbA1c levels between 7.0 and 9.0% (53‒75 mmol/mol). The intervention was once-weekly home monitoring of GA with a daily self-review of lifestyle behaviors using a smartphone application, in addition to conventional treatment. RESULTS: A total of 98 participants (72.0% males; age 63.2 ± 11.4 years; HbA1c 7.39 ± 0.39% [57.3 ± 4.3 mmol/mol]) were randomly assigned to the intervention or control group. Significant decreases of the GA and HbA1c levels from the baseline to the last observation day were observed in the intervention group (- 1.71 ± 1.37% [- 39.1 ± 31.3 mmol/mol] and - 0.32 ± 0.32% [- 3.5 ± 3.5 mmol/mol], respectively). Significant decreases of the body weight, waist circumference, and caloric expenditure (p < 0.0001 and p = 0.0003, p = 0.0346, respectively), but not of the caloric intake (p = 0.678), were also observed in the intervention group as compared with the control group. CONCLUSIONS: Self-review of lifestyle behaviors in combination with once-weekly GA home testing received via a smartphone application might potentially benefit glycemic management in people with type 2 diabetes mellitus. TRIAL REGISTRATION: jRCTs042220048.

11.
Neuron ; 112(13): 2157-2176.e12, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38697111

RESUMO

Mutations in human nonsense-mediated mRNA decay (NMD) factors are enriched in neurodevelopmental disorders. We show that deletion of key NMD factor Upf2 in mouse embryonic neural progenitor cells causes perinatal microcephaly but deletion in immature neurons does not, indicating NMD's critical roles in progenitors. Upf2 knockout (KO) prolongs the cell cycle of radial glia progenitor cells, promotes their transition into intermediate progenitors, and leads to reduced upper-layer neurons. CRISPRi screening identified Trp53 knockdown rescuing Upf2KO progenitors without globally reversing NMD inhibition, implying marginal contributions of most NMD targets to the cell cycle defect. Integrated functional genomics shows that NMD degrades selective TRP53 downstream targets, including Cdkn1a, which, without NMD suppression, slow the cell cycle. Trp53KO restores the progenitor cell pool and rescues the microcephaly of Upf2KO mice. Therefore, one physiological role of NMD in the developing brain is to degrade selective TRP53 targets to control progenitor cell cycle and brain size.


Assuntos
Encéfalo , Camundongos Knockout , Células-Tronco Neurais , Degradação do RNAm Mediada por Códon sem Sentido , Proteína Supressora de Tumor p53 , Animais , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Camundongos , Encéfalo/metabolismo , Células-Tronco Neurais/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido/genética , Epistasia Genética , Microcefalia/genética , Ciclo Celular/fisiologia , Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética
12.
Nat Commun ; 15(1): 2178, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467639

RESUMO

Immune checkpoint inhibitors targeting PD-1/L1 have modest efficacy in hepatocellular carcinoma as single agents. Targeting membranous phosphatidylserine may induce pro-inflammatory and -immune stimulating effects that enhance immunotherapy activity. This hypothesis was tested in a single-arm phase 2 trial evaluating frontline bavituximab, a phosphatidylserine targeting antibody, plus pembrolizumab (anti-PD-1) in patients with unresectable hepatocellular carcinoma (NCT03519997). The primary endpoint was investigator-assessed objective response rate among evaluable patients, and secondary end points included progression-free survival, incidence of adverse events, overall survival, and duration of response. Among 28 evaluable patients, the confirmed response rate was 32.1%, which met the pre-specified endpoint, and the median progression-free survival was 6.3 months (95% CI, 1.3-11.3 months). Treatment related-adverse events of any grade occurred in 45.7% of patients, with grade 3 or greater adverse events in 14.3% of patients. Adverse events of any cause were observed in 33 patients (94.3%), with grade 3 or greater adverse events in 11 patients (31.4%). Prespecified exploratory analyses of baseline tumor specimens showed that a depletion of B cells, and the presence of fibrotic tissue and expression of immune checkpoints in stroma was associated with tumor response. These results suggest that targeting phosphatidylserine may lead to synergistic effects with PD-1 blockade without increasing toxicity rates, and future studies on this therapeutic strategy may be guided by biomarkers characterizing the pre-treatment tumor microenvironment.


Assuntos
Anticorpos Monoclonais Humanizados , Anticorpos Monoclonais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Fosfatidilserinas , Receptor de Morte Celular Programada 1 , Neoplasias Hepáticas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Microambiente Tumoral
13.
J Diabetes Investig ; 15(6): 782-785, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38372649

RESUMO

The potential liability to hypercatabolism in lipodystrophy remains to be fully elucidated. Here we report a 28-year-old Japanese woman with acquired generalized lipodystrophy, who presented with recurrence of panniculitis and anemia. After corticosteroid treatment was started, she showed rapid reductions in body weight and lean mass by 15% at maximum, accompanied by an elevated urea nitrogen/creatinine ratio, which recovered almost fully as the corticosteroid treatment was tapered and discontinued. She had multiple risk factors for hypercatabolism: lack of metabolic reserves, insulin resistance, and hyperglycemia due to lipodystrophy, lowered daily activity due to anemia, persistent inflammation, and wasting associated with panniculitis, and relatively insufficient energy and protein intake during hospitalization. More attention should be paid to the potential liability to hypercatabolism in patients with lipodystrophy, and to skeletal muscle loss as an adverse effect of corticosteroid treatment in patients at high risk, such as those with diabetes or decreased metabolic reserves.


Assuntos
Lipodistrofia , Músculo Esquelético , Humanos , Feminino , Adulto , Lipodistrofia/induzido quimicamente , Lipodistrofia/complicações , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Músculo Esquelético/metabolismo , Corticosteroides/efeitos adversos , Corticosteroides/uso terapêutico
14.
Hormones (Athens) ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38396110

RESUMO

PURPOSE: According to the Japan National Health and Nutrition Survey 2019, the proportion of people with prediabetes is estimated to be 27.3%. Western-style dietary habits can lead to obesity and a functional abnormality of the adipose tissue, which can cause insulin resistance and predispose one to diabetes. We examined the relationship between insulin resistance using body adiposity parameters as surrogate markers. METHODS: This study enrolled 248 healthy participants to determine the association of six body adiposity parameters, namely, body mass index (BMI), waist circumference (WC), visceral adiposity index (VAI), lipid accumulation product index (LAP), waist circumference-triglyceride index (WTI), and triglyceride (TG)/high-density lipoprotein (HDL) ratio with insulin resistance. Receiver operating characteristics curve analyses were performed to assess the accuracy of these parameters in identifying insulin resistance. RESULTS: The data of the 248 participants (women 79 and men 169) were examined in this study. WC showed the highest accuracy in the obese women group (cut-off value: 89.8 with sensitivity: 0.900 and specificity: 0.522, AUC: 0.680) and men group (cut-off value: 90.0 with sensitivity: 0.862 and specificity: 0.508, AUC: 0.701). The TG/HDL ratio showed the highest accuracy in men with non-obesity (cut-off value: 0.8 with sensitivity: 0.857 and specificity: 0.649, AUC: 0.780). CONCLUSION: Application of this finding should be useful in the early screening of obesity in men with non-obesity, such as during regular health check-up with the TG/HDL ratio in addition to the usually used WC, to assess insulin resistance and prevent lifestyle-related diseases that can lead to cardiovascular events.

15.
Diabetes ; 73(3): 474-489, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064504

RESUMO

Genome-wide association studies have identified several gene polymorphisms, including UBE2E2, associated with type 2 diabetes. Although UBE2E2 is one of the ubiquitin-conjugating enzymes involved in the process of ubiquitin modifications, the pathophysiological roles of UBE2E2 in metabolic dysfunction are not yet understood. Here, we showed upregulated UBE2E2 expression in the islets of a mouse model of diet-induced obesity. The diabetes risk allele of UBE2E2 (rs13094957) in noncoding regions was associated with upregulation of UBE2E2 mRNA in the human pancreas. Although glucose-stimulated insulin secretion was intact in the isolated islets, pancreatic ß-cell-specific UBE2E2-transgenic (TG) mice exhibited reduced insulin secretion and decreased ß-cell mass. In TG mice, suppressed proliferation of ß-cells before the weaning period and while receiving a high-fat diet was accompanied by elevated gene expression levels of p21, resulting in decreased postnatal ß-cell mass expansion and compensatory ß-cell hyperplasia, respectively. In TG islets, proteomic analysis identified enhanced formation of various types of polyubiquitin chains, accompanied by increased expression of Nedd4 E3 ubiquitin protein ligase. Ubiquitination assays showed that UBE2E2 mediated the elongation of ubiquitin chains by Nedd4. The data suggest that UBE2E2-mediated ubiquitin modifications in ß-cells play an important role in regulating glucose homeostasis and ß-cell mass.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Células Secretoras de Insulina , Camundongos , Animais , Humanos , Intolerância à Glucose/genética , Intolerância à Glucose/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Estudo de Associação Genômica Ampla , Proteômica , Células Secretoras de Insulina/metabolismo , Glucose/metabolismo , Camundongos Transgênicos , Dieta Hiperlipídica/efeitos adversos , Ubiquitinas/genética , Ubiquitinas/metabolismo , Insulina/metabolismo
16.
Nat Commun ; 14(1): 6584, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37852976

RESUMO

Diabetes is known to increase the risk of nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). Here we treat male STAM (STelic Animal Model) mice, which develop diabetes, NASH and HCC associated with dysbiosis upon low-dose streptozotocin and high-fat diet (HFD), with insulin or phlorizin. Although both treatments ameliorate hyperglycemia and NASH, insulin treatment alone lead to suppression of HCC accompanied by improvement of dysbiosis and restoration of antimicrobial peptide production. There are some similarities in changes of microflora from insulin-treated patients comorbid with diabetes and NASH. Insulin treatment, however, fails to suppress HCC in the male STAM mice lacking insulin receptor specifically in intestinal epithelial cells (ieIRKO), which show dysbiosis and impaired gut barrier function. Furthermore, male ieIRKO mice are prone to develop HCC merely on HFD. These data suggest that impaired gut insulin signaling increases the risk of HCC, which can be countered by restoration of insulin action in diabetes.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus Experimental , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Fígado/patologia , Carcinoma Hepatocelular/patologia , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Disbiose/complicações , Disbiose/patologia , Neoplasias Hepáticas/patologia , Insulina , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças
17.
JCI Insight ; 8(17)2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37681411

RESUMO

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes are interacting comorbidities of obesity, and increased hepatic de novo lipogenesis (DNL), driven by hyperinsulinemia and carbohydrate overload, contributes to their pathogenesis. Fatty acid synthase (FASN), a key enzyme of hepatic DNL, is upregulated in association with insulin resistance. However, the therapeutic potential of targeting FASN in hepatocytes for obesity-associated metabolic diseases is unknown. Here, we show that hepatic FASN deficiency differentially affects NAFLD and diabetes depending on the etiology of obesity. Hepatocyte-specific ablation of FASN ameliorated NAFLD and diabetes in melanocortin 4 receptor-deficient mice but not in mice with diet-induced obesity. In leptin-deficient mice, FASN ablation alleviated hepatic steatosis and improved glucose tolerance but exacerbated fed hyperglycemia and liver dysfunction. The beneficial effects of hepatic FASN deficiency on NAFLD and glucose metabolism were associated with suppression of DNL and attenuation of gluconeogenesis and fatty acid oxidation, respectively. The exacerbation of fed hyperglycemia by FASN ablation in leptin-deficient mice appeared attributable to impairment of hepatic glucose uptake triggered by glycogen accumulation and citrate-mediated inhibition of glycolysis. Further investigation of the therapeutic potential of hepatic FASN inhibition for NAFLD and diabetes in humans should thus consider the etiology of obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintases , Hiperglicemia/complicações , Leptina , Óxido Nítrico Sintase , Obesidade/complicações , Obesidade/genética
18.
J Neurosci ; 43(43): 7226-7241, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37699718

RESUMO

The insulin/IGF-1 signaling (IIS) regulates a wide range of biological processes, including aging and lifespan, and has also been implicated in the pathogenesis of Alzheimer's disease (AD). We and others have reported that reduced signaling by genetic ablation of the molecules involved in IIS (e.g., insulin receptor substrate 2 [IRS-2]) markedly mitigates amyloid plaque formation in the brains of mouse models of AD, although the molecular underpinnings of the amelioration remain unsolved. Here, we revealed, by a transcriptomic analysis of the male murine cerebral cortices, that the expression of genes encoding extracellular matrix (ECM) was significantly upregulated by the loss of IRS-2. Insulin signaling activity negatively regulated the phosphorylation of Smad2 and Smad3 in the brain, and suppressed TGF-ß/Smad-dependent expression of a subset of ECM genes in brain-derived cells. The ECM proteins inhibited Aß fibril formation in vitro, and IRS-2 deficiency suppressed the aggregation process of Aß in the brains of male APP transgenic mice as revealed by injection of aggregation seeds in vivo Our results propose a novel mechanism in AD pathophysiology whereby IIS modifies Aß aggregation and amyloid pathology by altering the expression of ECM genes in the brain.SIGNIFICANCE STATEMENT The insulin/IGF-1 signaling (IIS) has been recognized as a regulator of aging, a leading risk factor for the onset of Alzheimer's disease (AD). In AD mouse models, genetic deletion of key IIS molecules markedly reduces the amyloid plaque formation in the brain, although the molecular underpinnings of this amelioration remain elusive. We found that the deficiency of insulin receptor substrate 2 leads to an increase in the expression of various extracellular matrices (ECMs) in the brain, potentially through TGF-ß/Smad signaling. Furthermore, some of those ECMs exhibited the potential to inhibit amyloid plaque accumulation by disrupting the formation of Aß fibrils. This study presents a novel mechanism by which IIS regulates Aß accumulation, which may involve altered brain ECM expression.


Assuntos
Doença de Alzheimer , Masculino , Camundongos , Animais , Doença de Alzheimer/metabolismo , Insulina , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Placa Amiloide/patologia , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Camundongos Transgênicos , Modelos Animais de Doenças , Fator de Crescimento Transformador beta/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo
19.
Nature ; 621(7978): 389-395, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37648852

RESUMO

Insulin resistance is the primary pathophysiology underlying metabolic syndrome and type 2 diabetes1,2. Previous metagenomic studies have described the characteristics of gut microbiota and their roles in metabolizing major nutrients in insulin resistance3-9. In particular, carbohydrate metabolism of commensals has been proposed to contribute up to 10% of the host's overall energy extraction10, thereby playing a role in the pathogenesis of obesity and prediabetes3,4,6. Nevertheless, the underlying mechanism remains unclear. Here we investigate this relationship using a comprehensive multi-omics strategy in humans. We combine unbiased faecal metabolomics with metagenomics, host metabolomics and transcriptomics data to profile the involvement of the microbiome in insulin resistance. These data reveal that faecal carbohydrates, particularly host-accessible monosaccharides, are increased in individuals with insulin resistance and are associated with microbial carbohydrate metabolisms and host inflammatory cytokines. We identify gut bacteria associated with insulin resistance and insulin sensitivity that show a distinct pattern of carbohydrate metabolism, and demonstrate that insulin-sensitivity-associated bacteria ameliorate host phenotypes of insulin resistance in a mouse model. Our study, which provides a comprehensive view of the host-microorganism relationships in insulin resistance, reveals the impact of carbohydrate metabolism by microbiota, suggesting a potential therapeutic target for ameliorating insulin resistance.


Assuntos
Metabolismo dos Carboidratos , Microbioma Gastrointestinal , Resistência à Insulina , Animais , Humanos , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Microbioma Gastrointestinal/fisiologia , Resistência à Insulina/fisiologia , Monossacarídeos/metabolismo , Insulina/metabolismo , Síndrome Metabólica/metabolismo , Fezes/química , Fezes/microbiologia , Metabolômica
20.
Diabetes Ther ; 14(10): 1711-1721, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37568043

RESUMO

INTRODUCTION: Hemoglobin A1c (HbA1c), representing the average blood glucose over 1-2 months, is the most commonly used glycemic marker in people with diabetes. Glycated albumin (GA) reflects the average blood glucose over the most recent 1-2 weeks. We considered whether the faster response of GA compared with HbA1c could make people with diabetes realize their glycemic control intuitively and effectively. METHODS: We randomized 61 people with diabetes into the control and intervention groups. Blood samples were collected from both every fortnight over an 8-week period (five times; visit 1-5). Only the intervention group was notified of the GA levels on the same day. At the beginning and end of the study, International Physical Activity Questionnaire and Eating Behavior Questionnaire assessments, and body composition measurements were conducted. RESULTS: The body weight change was significantly lower in the intervention group at visit 2 and visit 5. The percent body fat change was lower, while the percent skeletal muscle mass change at visit 5 was higher in the intervention group. Increasing GA trend was observed in the control group, but not in the intervention group. The fasting plasma glucose and HbA1c changes at visit 5 were similar in the two groups. Physical activity level change tended to be higher in the intervention group. The YN Eating Behavior Questionnaire score changes were similar in the two groups. CONCLUSION: Bi-weekly GA measurement over an 8-week period in people with type 2 diabetes induced behavioral changes. Development of this method is expected to improve diabetes management. TRIAL REGISTRATION: UMIN000037795.

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