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1.
Nutrients ; 16(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732511

RESUMO

Prenatal alcohol exposure (AE) affects cognitive development. However, it is unclear whether prenatal AE influences the metabolic health of offspring and whether postnatal AE exacerbates metabolic deterioration resulting from prenatal AE. Choline is a semi-essential nutrient that has been demonstrated to mitigate the cognitive impairment of prenatal AE. This study investigated how maternal choline supplementation (CS) may modify the metabolic health of offspring with prenatal and postnatal AE (AE/AE). C57BL/6J female mice were fed either a Lieber-DeCarli diet with 1.4% ethanol between embryonic day (E) 9.5 and E17.5 or a control diet. Choline was supplemented with 4 × concentrations versus the control throughout pregnancy. At postnatal week 7, offspring mice were exposed to 1.4% ethanol for females and 3.9% ethanol for males for 4 weeks. AE/AE increased hepatic triglyceride accumulation in male offspring only, which was normalized by prenatal CS. Prenatal CS also improved glucose tolerance compared to AE/AE animals. AE/AE suppressed hepatic gene expression of peroxisome proliferator activated receptor alpha (Ppara) and low-density lipoprotein receptor (Ldlr), which regulate fatty acid catabolism and cholesterol reuptake, respectively, in male offspring. However, these changes were not rectified by prenatal CS. In conclusion, AE/AE led to an increased risk of steatosis and was partially prevented by prenatal CS in male mice.


Assuntos
Colina , Suplementos Nutricionais , Etanol , Fígado , Camundongos Endogâmicos C57BL , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Gravidez , Colina/administração & dosagem , Masculino , Fígado/metabolismo , Fígado/efeitos dos fármacos , Camundongos , Fígado Gorduroso/prevenção & controle , Fígado Gorduroso/etiologia , Triglicerídeos/metabolismo , PPAR alfa/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Intolerância à Glucose/prevenção & controle , Metabolismo dos Lipídeos/efeitos dos fármacos
2.
BMC Pregnancy Childbirth ; 24(1): 356, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745311

RESUMO

BACKGROUND: Malaria in pregnancy can have adverse outcomes if untreated. Both malaria and pregnancy are associated with insulin resistance and diabetes. Although malaria is treated prophylactically with gestational diabetes mellitus (GDM) screened for in pregnancy as part a routine antenatal care, their impacts have not been examined in terms of other forms of dysglycaemia. This cross-sectional study examined insulin resistance and its relationship with dysglycaemia and malaria among pregnant women in the Cape Coast Teaching Hospital (CCTH). METHODS: Using a structured questionnaire, demographic and clinical information were obtained from 252 pregnant women aged 18-42 years. Weight and height were measured for computation of body mass index (BMI). Measurement of insulin, lipid profile and glucose were taken under fasting conditions followed by oral glucose tolerant test. Insulin resistance and beta-cell function were assessed by the homeostatic model as malaria was diagnosed by microscopy. RESULTS: The respective prevalence of GDM, gestational glucose intolerance (GGI) and insulin resistance were 0.8% (2/252), 19.44% (49/252) and 56.75% (143/252). No malaria parasite or dyslipidaemia was detected in any of the participants. Apart from BMI that increased across trimesters, no other measured parameter differed among the participants. Junior High School (JHS) education compared with no formal education increased the odds (AOR: 2.53; CI: 1.12-5.71; P = 0.03) but 2nd trimester of pregnancy compared to the 1st decreased the odds (AOR: 0.32; CI: 0.12-0.81; P = 0.02) of having insulin resistance in the entire sample. In a sub-group analysis across trimesters, pregnant women with JHS education in their 3rd trimester had increased odds (AOR: 4.41; CI: 1.25-15.62; P = 0.02) of having insulin resistance. CONCLUSION: Prevalence of GDM and GGI were 0.8% and 19.44% respectively. The odds of insulin resistance increased in pregnant women with JHS education in the 3rd trimester. Appropriate measures are needed to assuage the diabetogenic risk posed by GGI in our setting.


Assuntos
Diabetes Gestacional , Hospitais de Ensino , Resistência à Insulina , Humanos , Feminino , Gravidez , Adulto , Estudos Transversais , Diabetes Gestacional/epidemiologia , Adulto Jovem , Adolescente , Prevalência , África do Sul/epidemiologia , Malária/epidemiologia , Malária/sangue , Índice de Massa Corporal , Intolerância à Glucose/epidemiologia , Intolerância à Glucose/sangue , Teste de Tolerância a Glucose , Glicemia/análise , Glicemia/metabolismo , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/sangue , Escolaridade
3.
PLoS One ; 19(5): e0302777, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38701059

RESUMO

Achieving diabetes remission (HbA1c<48mmol/mol without the use of anti-diabetic medication for 3 months) might not assure restoration of a normal glycemic profile [fasting blood sugar level <5.6 mmol/L and Post-Prandial (PP) blood glucose <7.8mmol/L]. The study investigates the factors associated with OGTT clearance in patients under type 2 diabetes remission. Four hundred participants who achieved remission during a one-year online structured lifestyle modification program, which included a plant-based diet, physical activity, psychological support, and medical management (between January 2021 and June 2022), and appeared for the OGTT were included in the study. OGTT clearance was defined by fasting blood glucose < 5.6 mmol/L and 2-hour post-prandial blood glucose <7.8 mmol/L post-consumption of 75g glucose solution. Of the 400 participants, 207 (52%) cleared OGTT and 175 (44%) had impaired glucose tolerance (IGT). A shorter diabetes duration (<5 years) was significantly associated with OGTT clearance (p<0.05). Pre-intervention use of glucose-lowering drugs showed no association with OGTT clearance (p<0.1). Post-intervention, the OGTT-cleared group showed significantly higher weight loss (p<0.05) and a decrease in HbA1c compared to the IGT group (p<0.05). Improvement in Insulin resistance and ß-cell function was also higher in the OGTT-cleared group compared to the IGT group (p<0.05). In conclusion, clearing the OGTT is a possibility for those achieving remission through lifestyle interventions. Higher weight loss, a shorter duration of diabetes, and improvement in insulin resistance were significantly associated with OGTT clearance in participants in remission. Future randomized controlled trials with longer follow-ups may help substantiate our findings.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Teste de Tolerância a Glucose , Estilo de Vida , Humanos , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Glicemia/metabolismo , Glicemia/análise , Idoso , Indução de Remissão , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Intolerância à Glucose/terapia , Exercício Físico , Adulto
4.
BMC Res Notes ; 17(1): 128, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711110

RESUMO

The elemental composition of chemical elements can vary between healthy and diseased tissues, providing essential insights into metabolic processes in physiological and diseased states. This study aimed to evaluate the calcium (Ca) and phosphorus (P) levels in the bones of rats with/without streptozotocin-induced diabetes and/or exposure to infrasound. X-ray fluorescence spectroscopy was used to determine the concentrations of Ca and P in Wistar rat tibiae samples.The results showed a significant decrease in bone P concentration in streptozotocin-induced diabetic rats compared to untreated animals. Similarly, the Ca/P ratio was higher in the streptozotocin-induced diabetic group. No significant differences were observed in bone Ca concentration between the studied groups or between animals exposed and not exposed to infrasound.Moreover, streptozotocin-induced diabetic rats had lower bone P concentration but unaltered bone Ca concentration compared to untreated rats. Infrasound exposure did not impact bone Ca or P levels. The reduced bone P concentration may be associated with an increased risk of bone fractures in diabetes.


Assuntos
Cálcio , Diabetes Mellitus Experimental , Fósforo , Ratos Wistar , Estreptozocina , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Fósforo/metabolismo , Cálcio/metabolismo , Ratos , Masculino , Espectrometria por Raios X , Tíbia/metabolismo , Som/efeitos adversos , Osso e Ossos/metabolismo , Intolerância à Glucose/metabolismo
5.
Diabetes Metab Res Rev ; 40(4): e3808, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38711301

RESUMO

After reading the article written by Wang et al., we have encountered several concerns that may compromise the credibility of the article. There are some factors, such as changes in sleep patterns, glucose tolerance status, and the use of hypnotics, which may interfere with the research results. Additionally, the design of the sleep pattern could lead to biased outcomes. Therefore, we are writing this letter to recommend that further research should take these concerns into consideration.


Assuntos
Doenças Cardiovasculares , Intolerância à Glucose , Sono , Humanos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/epidemiologia , Sono/fisiologia , Glicemia/análise , Fatores de Risco , Fatores de Risco de Doenças Cardíacas , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/epidemiologia
6.
Sci Rep ; 14(1): 7670, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561446

RESUMO

Dietary factors such as food texture affect feeding behavior and energy metabolism, potentially causing obesity and type 2 diabetes. We previously found that rats fed soft pellets (SPs) were neither hyperphagic nor overweight but demonstrated glucose intolerance, insulin resistance, and hyperplasia of pancreatic ß-cells. In the present study, we investigated the mechanism of muscle atrophy in rats that had been fed SPs on a 3-h time-restricted feeding schedule for 24 weeks. As expected, the SP rats were normal weight; however, they developed insulin resistance, glucose intolerance, and fat accumulation. In addition, skeletal muscles of SP rats were histologically atrophic and demonstrated disrupted insulin signaling. Furthermore, we learned that the muscle atrophy of the SP rats developed via the IL-6-STAT3-SOCS3 and ubiquitin-proteasome pathways. Our data show that the dietary habit of consuming soft foods can lead to not only glucose intolerance or insulin resistance but also muscle atrophy.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Resistência à Insulina , Ratos , Animais , Resistência à Insulina/fisiologia , Intolerância à Glucose/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Insulina/metabolismo , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Músculo Esquelético/metabolismo , Dieta , Dieta Hiperlipídica
7.
Sci Rep ; 14(1): 8315, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594375

RESUMO

Latent autoimmune diabetes in adults (LADA) is a heterogeneous disease characterized by autoantibodies against insulin producing pancreatic beta cells and initial lack of need for insulin treatment. The aim of the present study was to investigate if individuals with LADA have an altered gut microbiota relative to non-diabetic control subjects, individuals with type 1 diabetes (T1D), and individuals with type 2 diabetes (T2D). Bacterial community profiling was performed with primers targeting the variable region 4 of the 16S rRNA gene and sequenced. Amplicon sequence variants (ASVs) were generated with DADA2 and annotated to the SILVA database. The gut virome was sequenced, using a viral particle enrichment and metagenomics approach, assembled, and quantified to describe the composition of the viral community. Comparison of the bacterial alpha- and beta-diversity measures revealed that the gut bacteriome of individuals with LADA resembled that of individuals with T2D. Yet, specific genera were found to differ in abundance in individuals with LADA compared with T1D and T2D, indicating that LADA has unique taxonomical features. The virome composition reflected the stability of the most dominant order Caudovirales and the families Siphoviridae, Podoviridae, and Inoviridae, and the dominant family Microviridae. Further studies are needed to confirm these findings.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Intolerância à Glucose , Diabetes Autoimune Latente em Adultos , Adulto , Humanos , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Autoimune Latente em Adultos/genética , Microbioma Gastrointestinal/genética , Adenosina Desaminase , RNA Ribossômico 16S/genética , Peptídeos e Proteínas de Sinalização Intercelular , Insulina
8.
Metabolism ; 155: 155910, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599278

RESUMO

BACKGROUND: Weight loss and lifestyle intervention improve glucose tolerance delaying the onset of type 2 diabetes (T2D), but individual responses are highly variable. Determining the predictive factors linked to the beneficial effects of weight loss on glucose tolerance could provide tools for individualized prevention plans. Thus, the aim was to investigate the relationship between pre-intervention values of insulin sensitivity and secretion and the improvement in glucose metabolism after weight loss. METHODS: In the DEXLIFE cohort (373 individuals at high risk of T2D, assigned 3:1 to a 12-week lifestyle intervention or a control arm, Trial Registration: ISRCTN66987085), K-means clustering and logistic regression analysis were performed based on pre-intervention indices of insulin sensitivity, insulin secretion (AUC-I), and glucose-stimulated insulin response (ratio of incremental areas of insulin and glucose, iAUC I/G). The response to the intervention was evaluated in terms of reduction of OGTT-glucose concentration. Clusters' validation was done in the prospective EGIR-RISC cohort (n = 1538). RESULTS: Four replicable clusters with different glycemic and metabolomic profiles were identified. Individuals had similar weight loss, but improvement in glycemic profile and ß-cell function was different among clusters, highly depending on pre-intervention insulin response to OGTT. Pre-intervention high insulin response was associated with the best improvement in AUC-G, while clusters with low AUC-I and iAUC I/G showed no beneficial effect of weight loss on glucose control, as also confirmed by the logistic regression model. CONCLUSIONS: Individuals with preserved ß-cell function and high insulin concentrations at baseline have the best improvement in glucose tolerance after weight loss.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Insulina , Fenótipo , Redução de Peso , Humanos , Redução de Peso/fisiologia , Células Secretoras de Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Masculino , Feminino , Insulina/sangue , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/sangue , Estudos Prospectivos , Glicemia/metabolismo , Glicemia/análise , Adulto , Resistência à Insulina/fisiologia , Teste de Tolerância a Glucose , Intolerância à Glucose , Secreção de Insulina , Estilo de Vida , Idoso
9.
Front Endocrinol (Lausanne) ; 15: 1376530, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681771

RESUMO

Background/Objectives: Glucagon is important in the maintenance of glucose homeostasis, with also effects on lipids. In this study, we aimed to apply a recently developed model of glucagon kinetics to determine the sensitivity of glucagon variations (especially, glucagon inhibition) to insulin levels ("alpha-cell insulin sensitivity"), during oral glucose administration. Subjects/Methods: We studied 50 participants (spanning from normal glucose tolerance to type 2 diabetes) undergoing frequently sampled 5-hr oral glucose tolerance test (OGTT). The alpha-cell insulin sensitivity and the glucagon kinetics were assessed by a mathematical model that we developed previously. Results: The alpha-cell insulin sensitivity parameter (named SGLUCA; "GLUCA": "glucagon") was remarkably variable among participants (CV=221%). SGLUCA was found inversely correlated with the mean glycemic values, as well as with 2-hr glycemia of the OGTT. When stratifying participants into two groups (normal glucose tolerance, NGT, N=28, and impaired glucose regulation/type 2 diabetes, IGR_T2D, N=22), we found that SGLUCA was lower in the latter (1.50 ± 0.50·10-2 vs. 0.26 ± 0.14·10-2 ng·L-1 GLUCA/pmol·L-1 INS, in NGT and IGR_T2D, respectively, p=0.009; "INS": "insulin"). Conclusions: The alpha-cell insulin sensitivity is highly variable among subjects, and it is different in groups at different glucose tolerance. This may be relevant for defining personalized treatment schemes, in terms of dietary prescriptions but also for treatments with glucagon-related agents.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Glucagon , Teste de Tolerância a Glucose , Glucose , Resistência à Insulina , Humanos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Glucagon/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Glicemia/metabolismo , Glicemia/análise , Adulto , Glucose/metabolismo , Glucose/administração & dosagem , Modelos Teóricos , Insulina/sangue , Insulina/administração & dosagem , Idoso , Células Secretoras de Glucagon/metabolismo , Células Secretoras de Glucagon/efeitos dos fármacos , Administração Oral , Cinética , Intolerância à Glucose/sangue , Intolerância à Glucose/metabolismo
10.
Am J Physiol Endocrinol Metab ; 326(5): E663-E672, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568150

RESUMO

Despite the fact that genes and the environment are known to play a central role in islet function, our knowledge of how these parameters interact to modulate insulin secretory function remains relatively poor. Presently, we performed ex vivo glucose-stimulated insulin secretion and insulin content assays in islets of 213 mice from 13 inbred mouse strains on chow, Western diet (WD), and a high-fat, carbohydrate-free (KETO) diet. Strikingly, among these 13 strains, islets from the commonly used C57BL/6J mouse strain were the least glucose responsive. Using matched metabolic phenotyping data, we performed correlation analyses of isolated islet parameters and found a positive correlation between basal and glucose-stimulated insulin secretion, but no relationship between insulin secretion and insulin content. Using in vivo metabolic measures, we found that glucose tolerance determines the relationship between ex vivo islet insulin secretion and plasma insulin levels. Finally, we showed that islet glucose-stimulated insulin secretion decreased with KETO in almost all strains, concomitant with broader phenotypic changes, such as increased adiposity and glucose intolerance. This is an important finding as it should caution against the application of KETO diet for beta-cell health. Together these data offer key insights into the intersection of diet and genetic background on islet function and whole body glucose metabolism.NEW & NOTEWORTHY Thirteen strains of mice on chow, Western diet, and high-fat, carbohydrate-free (KETO), correlating whole body phenotypes to ex vivo pancreatic islet functional measurements, were used. The study finds a huge spectrum of functional islet responses and insulin phenotypes across all strains and diets, with the ubiquitous C57Bl/6J mouse exhibiting the lowest secretory response of all strains, highlighting the overall importance of considering genetic background when investigating islet function. Ex vivo basal and stimulated insulin secretion are correlated in the islet, and KETO imparts widescale downregulation of islet insulin secretion.


Assuntos
Dieta Hiperlipídica , Secreção de Insulina , Insulina , Ilhotas Pancreáticas , Camundongos Endogâmicos C57BL , Animais , Camundongos , Ilhotas Pancreáticas/metabolismo , Secreção de Insulina/fisiologia , Insulina/metabolismo , Insulina/sangue , Masculino , Dieta Ocidental , Glucose/metabolismo , Dieta com Restrição de Carboidratos , Camundongos Endogâmicos , Glicemia/metabolismo , Intolerância à Glucose/metabolismo , Intolerância à Glucose/genética
11.
Biol Pharm Bull ; 47(3): 739-749, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556303

RESUMO

Patients with diabetes exhibit altered taste sensitivity, but its details have not been clarified yet. Here, we examined alteration of sweet taste sensitivity with development of glucose intolerance in Otsuka Long-Evans Tokushima Fatty (OLETF) rats as a model of non-insulin-dependent diabetes mellitus. Compared to the cases of Long Evans Tokushima Otsuka (LETO) rats as a control, glucose tolerance of OLETF rats decreased with aging, resulting in development of diabetes at 36-weeks-old. In brief-access tests with a mixture of sucrose and quinine hydrochloride, OLETF rats at 25 or more-weeks-old seemed to exhibit lower sweet taste sensitivity than age-matched LETO ones, but the lick ratios of LETO, but not OLETF, rats for the mixture and quinine hydrochloride solutions decreased and increased, respectively, aging-dependently. Expression of sweet taste receptors, T1R2 and T1R3, in circumvallate papillae (CP) was almost the same in LETO and OLETF rats at 10- and 40-weeks-old, while expression levels of a bitter taste receptor, T2R16, were greater in 40-weeks-old rats than in 10-weeks-old ones in both strains. There was no apparent morphological alteration in taste buds in CP between 10- and 40-weeks-old LETO and OLETF rats. Metagenomic analysis of gut microbiota revealed strain- and aging-dependent alteration of mucus layer-regulatory microbiota. Collectively, we concluded that the apparent higher sweet taste sensitivity in 25 or more-weeks-old OLETF rats than in age-matched LETO rats was due to the aging-dependent increase of bitter taste sensitivity in LETO rats with alteration of the gut microbiota.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Humanos , Ratos , Animais , Ratos Endogâmicos OLETF , Paladar , Peso Corporal , Disgeusia , Quinina/farmacologia , Teste de Tolerância a Glucose , Diabetes Mellitus Tipo 2/metabolismo , Ratos Long-Evans , Glicemia/análise
12.
Am J Physiol Endocrinol Metab ; 326(5): E567-E576, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38477664

RESUMO

Signaling through prostaglandin E2 EP3 receptor (EP3) actively contributes to the ß-cell dysfunction of type 2 diabetes (T2D). In T2D models, full-body EP3 knockout mice have a significantly worse metabolic phenotype than wild-type controls due to hyperphagia and severe insulin resistance resulting from loss of EP3 in extra-pancreatic tissues, masking any potential beneficial effects of EP3 loss in the ß cell. We hypothesized ß-cell-specific EP3 knockout (EP3 ßKO) mice would be protected from high-fat diet (HFD)-induced glucose intolerance, phenocopying mice lacking the EP3 effector, Gαz, which is much more limited in its tissue distribution. When fed a HFD for 16 wk, though, EP3 ßKO mice were partially, but not fully, protected from glucose intolerance. In addition, exendin-4, an analog of the incretin hormone, glucagon-like peptide 1, more strongly potentiated glucose-stimulated insulin secretion in islets from both control diet- and HFD-fed EP3 ßKO mice as compared with wild-type controls, with no effect of ß-cell-specific EP3 loss on islet insulin content or markers of replication and survival. However, after 26 wk of diet feeding, islets from both control diet- and HFD-fed EP3 ßKO mice secreted significantly less insulin as a percent of content in response to stimulatory glucose, with or without exendin-4, with elevated total insulin content unrelated to markers of ß-cell replication and survival, revealing severe ß-cell dysfunction. Our results suggest that EP3 serves a critical role in temporally regulating ß-cell function along the progression to T2D and that there exist Gαz-independent mechanisms behind its effects.NEW & NOTEWORTHY The EP3 receptor is a strong inhibitor of ß-cell function and replication, suggesting it as a potential therapeutic target for the disease. Yet, EP3 has protective roles in extrapancreatic tissues. To address this, we designed ß-cell-specific EP3 knockout mice and subjected them to high-fat diet feeding to induce glucose intolerance. The negative metabolic phenotype of full-body knockout mice was ablated, and EP3 loss improved glucose tolerance, with converse effects on islet insulin secretion and content.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Células Secretoras de Insulina , Animais , Camundongos , Secreção de Insulina , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Exenatida/farmacologia , Intolerância à Glucose/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Obesidade/metabolismo , Glucose/metabolismo , Camundongos Knockout , Prostaglandinas/metabolismo , Prostaglandinas/farmacologia
15.
Arterioscler Thromb Vasc Biol ; 44(5): 1101-1113, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38545783

RESUMO

BACKGROUND: Much of what we know about insulin resistance is based on studies from metabolically active tissues such as the liver, adipose tissue, and skeletal muscle. Emerging evidence suggests that the vascular endothelium plays a crucial role in systemic insulin resistance; however, the underlying mechanisms remain incompletely understood. Arf6 (ADP ribosylation factor 6) is a small GTPase that plays a critical role in endothelial cell function. Here, we tested the hypothesis that the deletion of endothelial Arf6 will result in systemic insulin resistance. METHODS: We used mouse models of constitutive endothelial cell-specific Arf6 deletion (Arf6f/- Tie2Cre+) and tamoxifen-inducible Arf6 knockout (Arf6f/f Cdh5CreER+). Endothelium-dependent vasodilation was assessed using pressure myography. Metabolic function was assessed using a battery of metabolic assessments including glucose and insulin tolerance tests and hyperinsulinemic-euglycemic clamps. We used a fluorescence microsphere-based technique to measure tissue blood flow. Skeletal muscle capillary density was assessed using intravital microscopy. RESULTS: Endothelial Arf6 deletion impaired insulin-stimulated vasodilation in white adipose tissue and skeletal muscle feed arteries. The impairment in vasodilation was primarily due to attenuated insulin-stimulated nitric oxide bioavailability but independent of altered acetylcholine-mediated or sodium nitroprusside-mediated vasodilation. Endothelial cell-specific deletion of Arf6 also resulted in systematic insulin resistance in normal chow-fed mice and glucose intolerance in high-fat diet-fed obese mice. The underlying mechanisms of glucose intolerance were reductions in insulin-stimulated blood flow and glucose uptake in the skeletal muscle and were independent of changes in capillary density or vascular permeability. CONCLUSIONS: Results from this study support the conclusion that endothelial Arf6 signaling is essential for maintaining insulin sensitivity. Reduced expression of endothelial Arf6 impairs insulin-mediated vasodilation and results in systemic insulin resistance. These results have therapeutic implications for diseases that are associated with endothelial cell dysfunction and insulin resistance such as diabetes.


Assuntos
Fator 6 de Ribosilação do ADP , Endotélio , Resistência à Insulina , Músculo Esquelético , Camundongos , Fator 6 de Ribosilação do ADP/genética , Fator 6 de Ribosilação do ADP/metabolismo , Endotélio/metabolismo , Camundongos Endogâmicos C57BL , Intolerância à Glucose , Tamoxifeno , Camundongos Knockout , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Obesidade/metabolismo , Obesidade/patologia , Glucose/metabolismo , Dieta Hiperlipídica , Camundongos Obesos , Vasodilatação
16.
Diabetes Obes Metab ; 26(6): 2158-2166, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38433703

RESUMO

AIM: Type 1 diabetes results from autoimmune events influenced by environmental variables, including changes in diet. This study investigated how feeding refined versus unrefined (aka 'chow') diets affects the onset and progression of hyperglycaemia in non-obese diabetic (NOD) mice. METHODS: Female NOD mice were fed either unrefined diets or matched refined low- and high-fat diets. The onset of hyperglycaemia, glucose tolerance, food intake, energy expenditure, circulating insulin, liver gene expression and microbiome changes were measured for each dietary group. RESULTS: NOD mice consuming unrefined (chow) diets developed hyperglycaemia at similar frequencies. By contrast, mice consuming the defined high-fat diet had an accelerated onset of hyperglycaemia compared to the matched low-fat diet. There was no change in food intake, energy expenditure, or physical activity within each respective dietary group. Microbiome changes were driven by diet type, with chow diets clustering similarly, while refined low- and high-fat bacterial diversity also grouped closely. In the defined dietary cohort, liver gene expression changes in high-fat-fed mice were consistent with a greater frequency of hyperglycaemia and impaired glucose tolerance. CONCLUSION: Glucose intolerance is associated with an enhanced frequency of hyperglycaemia in female NOD mice fed a defined high-fat diet. Using an appropriate matched control diet is an essential experimental variable when studying changes in microbiome composition and diet as a modifier of disease risk.


Assuntos
Diabetes Mellitus Tipo 1 , Dieta Hiperlipídica , Hiperglicemia , Camundongos Endogâmicos NOD , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/microbiologia , Camundongos , Hiperglicemia/etiologia , Intolerância à Glucose/etiologia , Metabolismo Energético , Fígado/metabolismo , Dieta com Restrição de Gorduras , Insulina/metabolismo , Insulina/sangue , Glicemia/metabolismo
17.
Mol Cell Endocrinol ; 586: 112195, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38432501

RESUMO

Homocysteine (Hcy) is a sulfur-containing amino acid. An elevated level of Hcy is a risk factor for diabetes development. However, the mechanism of its effect on pancreatic ß-cell function is unclear. In this study, we constructed a hyperhomocysteinemia (HHcy) mouse model by feeding mice a high methionine diet (HMD). The mice suffered impaired glucose tolerance and reduced insulin secretion. Furthermore, at the cellular level, INS1 cells exhibited impaired insulin secretory function after the Hcy intervention. Transcriptomics revealed that Zbtb20 expression was downregulated and the downstream gene Fbp1 was upregulated in HHcy-induced mice compared with mice fed with normal diet. Insulin secretion could be restored by Zbtb20 overexpression or fructose 1,6-bisphosphatase (FBPase) activity inhibition in INS1 cells. In conclusion, our study suggested that Hcy inhibited the insulin secretory function of pancreatic ß-cells by suppressing Zbtb20 expression, leading to the development of diabetes. Zbtb20 may be a key target in the development of diabetes associated with elevated Hcy levels.


Assuntos
Diabetes Mellitus , Intolerância à Glucose , Camundongos , Animais , Insulina/metabolismo , Secreção de Insulina , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
J Nutr ; 154(5): 1505-1516, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460786

RESUMO

BACKGROUND: Sterol regulatory element binding protein (SREBP) 1 is considered to be a crucial regulator for lipid synthesis in vertebrates. However, whether SREBP1 could regulate hepatic gluconeogenesis under high-fat diet (HFD) condition is still unknown, and the underlying mechanism is also unclear. OBJECTIVES: This study aimed to determine gluconeogenesis-related gene and protein expressions in response to HFD in large yellow croaker and explore the role and mechanism of SREBP1 in regulating the related transcription and signaling. METHODS: Croakers (mean weight, 15.61 ± 0.10 g) were fed with diets containing 12% crude lipid [control diet (ND)] or 18% crude lipid (HFD) for 10 weeks. The glucose tolerance, insulin tolerance, hepatic gluconeogenesis-related genes, and proteins expressions were determined. To explore the role of SREBP1 in HFD-induced gluconeogenesis, SREBP1 was inhibited by pharmacologic inhibitor (fatostatin) or genetic knockdown in croaker hepatocytes under palmitic acid (PA) condition. To explore the underlying mechanism, luciferase reporter and chromatin immunoprecipitation assays were conducted in HEK293T cells. Data were analyzed using analysis of variance or Student t test. RESULTS: Compared with ND, HFD increased the mRNA expressions of gluconeogenesis genes (2.40-fold to 2.60-fold) (P < 0.05) and reduced protein kinase B (AKT) phosphorylation levels (0.28-fold to 0.34-fold) (P < 0.05) in croakers. However, inhibition of SREBP1 by fatostatin addition or SREBP1 knockdown reduced the mRNA expressions of gluconeogenesis genes (P < 0.05) and increased AKT phosphorylation levels (P < 0.05) in hepatocytes, compared with that by PA treatment. Moreover, fatostatin addition or SREBP1 knockdown also increased the mRNA expressions of irs1 (P < 0.05) and reduced serine phosphorylation of IRS1 (P < 0.05). Furthermore, SREBP1 inhibited IRS1 transcriptions by binding to its promoter and induced IRS1 serine phosphorylation by activating diacylglycerol-protein kinase Cε signaling. CONCLUSIONS: This study reveals the role of SREBP1 in hepatic gluconeogenesis under HFD condition in croakers, which may provide a potential strategy for improving HFD-induced glucose intolerance.


Assuntos
Dieta Hiperlipídica , Gluconeogênese , Intolerância à Glucose , Fígado , Proteína de Ligação a Elemento Regulador de Esterol 1 , Animais , Gluconeogênese/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Humanos , Intolerância à Glucose/metabolismo , Hepatócitos/metabolismo , Hepatócitos/efeitos dos fármacos , Células HEK293 , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Transdução de Sinais
19.
J Nutr Biochem ; 128: 109618, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38462210

RESUMO

A maternal low-protein diet during pregnancy can increase children's susceptibility to diabetes mellitus in adulthood. However, whether long noncoding RNAs (lncRNAs) in islets participate in the development of diabetes in adult offspring following maternal protein restriction is not fully understood. Female mice were fed a low-protein (LP) diet or control diet throughout gestation and lactation. The male offspring were then randomly divided into two groups according to maternal diet: offspring from control diet group dams (Ctrl group) and offspring from LP group dams (LP group). We observed the glucose metabolism of adult offspring. A lncRNA microarray was constructed for the islets from the LP group and Ctrl group to explore the differently expressed lncRNAs. Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes analyses were subsequently used to predict the functions of the differently expressed lncRNAs. The body weight from birth to 12 weeks of age was significantly lower in the LP offspring. Adult LP offspring exhibited impaired glucose tolerance and decreased insulin secretion, consistent with the reduction in ß-cell proliferation. According to the lncRNA microarray, four lncRNAs, three upregulated lncRNAs, and one downregulated lncRNA were differently expressed in LP offspring islets compared with Ctrl offspring. Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that these differentially expressed lncRNAs were mostly associated with the hypoxia-inducible factor-1α signaling pathway. Additionally, we validated the expression of these four differentially expressed lncRNAs via quantitative real-time polymerase chain reaction. Our findings demonstrated the expression patterns of lncRNAs in islets from adult offspring of mothers who consumed a maternal low-protein diet.


Assuntos
Dieta com Restrição de Proteínas , Ilhotas Pancreáticas , Fenômenos Fisiológicos da Nutrição Materna , RNA Longo não Codificante , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Feminino , Gravidez , Masculino , Ilhotas Pancreáticas/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Camundongos , Camundongos Endogâmicos C57BL , Insulina/metabolismo , Glucose/metabolismo , Intolerância à Glucose/metabolismo
20.
Diabetes Res Clin Pract ; 209: 111589, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38458916

RESUMO

Many individuals with intermediate hyperglycaemia (IH), including impaired fasting glycaemia (IFG) and impaired glucose tolerance (IGT), as presently defined, will progress to type 2 diabetes (T2D). There is confirmatory evidence that T2D can be prevented by lifestyle modification and/or medications, in people with IGT diagnosed by 2-h plasma glucose (PG) during a 75-gram oral glucose tolerance test (OGTT). Over the last 40 years, a wealth of epidemiological data has confirmed the superior value of 1-h plasma glucose (PG) over fasting PG (FPG), glycated haemoglobin (HbA1c) and 2-h PG in populations of different ethnicity, sex and age in predicting diabetes and associated complications including death. Given the relentlessly rising prevalence of diabetes, a more sensitive, practical method is needed to detect people with IH and T2D for early prevention or treatment in the often lengthy trajectory to T2D and its complications. The International Diabetes Federation (IDF) Position Statement reviews findings that the 1-h post-load PG ≥ 155 mg/dL (8.6 mmol/L) in people with normal glucose tolerance (NGT) during an OGTT is highly predictive for detecting progression to T2D, micro- and macrovascular complications, obstructive sleep apnoea, cystic fibrosis-related diabetes mellitus, metabolic dysfunction-associated steatotic liver disease, and mortality in individuals with risk factors. The 1-h PG of 209 mg/dL (11.6 mmol/L) is also diagnostic of T2D. Importantly, the 1-h PG cut points for diagnosing IH and T2D can be detected earlier than the recommended 2-h PG thresholds. Taken together, the 1-h PG provides an opportunity to avoid misclassification of glycaemic status if FPG or HbA1c alone are used. The 1-h PG also allows early detection of high-risk people for intervention to prevent progression to T2D which will benefit the sizeable and growing population of individuals at increased risk of T2D. Using a 1-h OGTT, subsequent to screening with a non-laboratory diabetes risk tool, and intervening early will favourably impact the global diabetes epidemic. Health services should consider developing a policy for screening for IH based on local human and technical resources. People with a 1-h PG ≥ 155 mg/dL (8.6 mmol/L) are considered to have IH and should be prescribed lifestyle intervention and referred to a diabetes prevention program. People with a 1-h PG ≥ 209 mg/dL (11.6 mmol/L) are considered to have T2D and should have a repeat test to confirm the diagnosis of T2D and then referred for further evaluation and treatment. The substantive data presented in the Position Statement provides strong evidence for redefining current diagnostic criteria for IH and T2D by adding the 1-h PG.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Hiperglicemia , Estado Pré-Diabético , Humanos , Hiperglicemia/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Glicemia/metabolismo , Jejum
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