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1.
Mol Cancer ; 23(1): 90, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711083

RESUMEN

BACKGROUND: Metabolic reprogramming and epigenetic alterations contribute to the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). Lactate-dependent histone modification is a new type of histone mark, which links glycolysis metabolite to the epigenetic process of lactylation. However, the role of histone lactylation in PDAC remains unclear. METHODS: The level of histone lactylation in PDAC was identified by western blot and immunohistochemistry, and its relationship with the overall survival was evaluated using a Kaplan-Meier survival plot. The participation of histone lactylation in the growth and progression of PDAC was confirmed through inhibition of histone lactylation by glycolysis inhibitors or lactate dehydrogenase A (LDHA) knockdown both in vitro and in vivo. The potential writers and erasers of histone lactylation in PDAC were identified by western blot and functional experiments. The potential target genes of H3K18 lactylation (H3K18la) were screened by CUT&Tag and RNA-seq analyses. The candidate target genes TTK protein kinase (TTK) and BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) were validated through ChIP-qPCR, RT-qPCR and western blot analyses. Next, the effects of these two genes in PDAC were confirmed by knockdown or overexpression. The interaction between TTK and LDHA was identified by Co-IP assay. RESULTS: Histone lactylation, especially H3K18la level was elevated in PDAC, and the high level of H3K18la was associated with poor prognosis. The suppression of glycolytic activity by different kinds of inhibitors or LDHA knockdown contributed to the anti-tumor effects of PDAC in vitro and in vivo. E1A binding protein p300 (P300) and histone deacetylase 2 were the potential writer and eraser of histone lactylation in PDAC cells, respectively. H3K18la was enriched at the promoters and activated the transcription of mitotic checkpoint regulators TTK and BUB1B. Interestingly, TTK and BUB1B could elevate the expression of P300 which in turn increased glycolysis. Moreover, TTK phosphorylated LDHA at tyrosine 239 (Y239) and activated LDHA, and subsequently upregulated lactate and H3K18la levels. CONCLUSIONS: The glycolysis-H3K18la-TTK/BUB1B positive feedback loop exacerbates dysfunction in PDAC. These findings delivered a new exploration and significant inter-relationship between lactate metabolic reprogramming and epigenetic regulation, which might pave the way toward novel lactylation treatment strategies in PDAC therapy.


Asunto(s)
Carcinoma Ductal Pancreático , Regulación Neoplásica de la Expresión Génica , Glucólisis , Histonas , L-Lactato Deshidrogenasa , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/genética , Humanos , Histonas/metabolismo , Animales , Línea Celular Tumoral , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Ratones , Retroalimentación Fisiológica , Epigénesis Genética , Carcinogénesis/metabolismo , Carcinogénesis/genética , Pronóstico , Proliferación Celular , Femenino
2.
Diabetes ; 73(6): 926-940, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38471012

RESUMEN

Sodium-glucose cotransporter 2 inhibitors, efficacious antidiabetic agents that have cardiovascular and renal benefits, can promote pancreatic ß-cell regeneration in type 2 diabetic mice. However, the underlying mechanism remains unclear. In this study, we aimed to use multiomics to identify the mediators involved in ß-cell regeneration induced by dapagliflozin. We showed that dapagliflozin lowered blood glucose level, upregulated plasma insulin level, and increased islet area in db/db mice. Dapagliflozin reshaped gut microbiota and modulated microbiotic and plasmatic metabolites related to tryptophan metabolism, especially l-tryptophan, in the diabetic mice. Notably, l-tryptophan upregulated the mRNA level of glucagon-like peptide 1 (GLP-1) production-related gene (Gcg and Pcsk1) expression and promoted GLP-1 secretion in cultured mouse intestinal L cells, and it increased the supernatant insulin level in primary human islets, which was eliminated by GPR142 antagonist. Transplant of fecal microbiota from dapagliflozin-treated mice, supplementation of l-tryptophan, or treatment with dapagliflozin upregulated l-tryptophan, GLP-1, and insulin or C-peptide levels and promoted ß-cell regeneration in db/db mice. Addition of exendin 9-39, a GLP-1 receptor (GLP-1R) antagonist, or pancreatic Glp1r knockout diminished these beneficial effects. In summary, treatment with dapagliflozin in type 2 diabetic mice promotes ß-cell regeneration by upregulating GLP-1 production, which is mediated via gut microbiota and tryptophan metabolism.


Asunto(s)
Compuestos de Bencidrilo , Microbioma Gastrointestinal , Péptido 1 Similar al Glucagón , Glucósidos , Células Secretoras de Insulina , Regeneración , Triptófano , Animales , Compuestos de Bencidrilo/farmacología , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Péptido 1 Similar al Glucagón/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Triptófano/metabolismo , Ratones , Glucósidos/farmacología , Glucósidos/uso terapéutico , Regeneración/efectos de los fármacos , Humanos , Masculino , Insulina/metabolismo , Glucemia/metabolismo , Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/microbiología , Ratones Endogámicos C57BL , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacología , Diabetes Mellitus Experimental/metabolismo , Receptor del Péptido 1 Similar al Glucagón/metabolismo
3.
J Diabetes Investig ; 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38429969

RESUMEN

Diabetes mellitus (DM) and arginine vasopressin deficiency (AVP-D) are characterized by polyuria. Marfan syndrome is an autosomal dominant disorder caused by pathogenetic variants in FBN1. Here, we report a patient with type 2 diabetes mellitus, AVP-D, and Marfan syndrome. Although the coexistence of type 2 diabetes mellitus and AVP-D is rare, for those patients with type 2 diabetes mellitus, the existence of AVP-D should be considered when polyuria is not in accordance with the blood glucose levels, especially for those with a low urine specific gravity. Specific symptoms or signs help to identify Marfan syndrome early, and genetic testing of the FBN1 pathogenetic variant helps to make a definitive diagnosis.

4.
J Diabetes Investig ; 15(3): 275-281, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38063248

RESUMEN

This report describes a patient who developed recurrent hypoglycemia episodes after 23 days of antiplatelet therapy with clopidogrel for left subclavian artery stent implantation. The patient suffered from palpitation, profuse sweating and weakness on the 23rd day of clopidogrel treatment. The minimum plasma glucose was 2.2 mmol/L, and the hypoglycemia was associated with significantly elevated levels of insulin. A diagnosis of insulin autoimmune syndrome (IAS) was made with the presence of insulin autoantibody and a comprehensive differential diagnosis of other conditions related with hypoglycemia. Clopidogrel was stopped, and the patient was treated with acarbose and had frequent low-carbohydrate meals; his hypoglycemia did not occur within 10 days. To date, seven cases of IAS induced by clopidogrel have been reported. Most reported cases were male aged in their 70s, and the hypoglycemic attack appeared 1-4 weeks after exposure to clopidogrel, characterized by severe hyperinsulinemia hypoglycemia with high titers of insulin autoantibodies. Most IAS cases can resolve spontaneously when they stop using the trigger medicine. Severe cases had been treated with drugs that reduce pancreatic insulin secretion (such as somatostatin and diazoxide), immunosuppressants (glucocorticoids, azathioprine and rituximab) and even immunoadsorption to remove the insulin autoantibody from the body. Considering the hypoglycemic attack might increase the risk of cardiovascular events among patients taking clopidogrel, we recommend that doctors should be aware of IAS as a rare severe adverse effect of clopidogrel, and be vigilant for the symptoms related with hypoglycemia in clopidogrel users.


Asunto(s)
Enfermedades Autoinmunes , Hiperinsulinismo , Hipoglucemia , Humanos , Masculino , Femenino , Clopidogrel , Hipoglucemia/inducido químicamente , Hipoglucemiantes , Insulina , Autoanticuerpos
5.
J Diabetes ; 15(12): 1081-1094, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37596940

RESUMEN

INTRODUCTION: The role of cardiac microvascular endothelial cells (CMECs) in diabetic cardiomyopathy is not fully understood. We aimed to investigate whether a glucagon receptor (GCGR) monoclonal antibody (mAb) ameliorated diabetic cardiomyopathy and clarify whether and how CMECs participated in the process. RESEARCH DESIGN AND METHODS: The db/db mice were treated with GCGR mAb or immunoglobulin G (as control) for 4 weeks. Echocardiography was performed to evaluate cardiac function. Immunofluorescent staining was used to determine microvascular density. The proteomic signature in isolated primary CMECs was analyzed by using tandem mass tag-based quantitative proteomic analysis. Some target proteins were verified by using western blot. RESULTS: Compared with db/m mice, cardiac microvascular density and left ventricular diastolic function were significantly reduced in db/db mice, and this reduction was attenuated by GCGR mAb treatment. A total of 199 differentially expressed proteins were upregulated in db/db mice versus db/m mice and downregulated in GCGR mAb-treated db/db mice versus db/db mice. The enrichment analysis demonstrated that fatty acid ß-oxidation and mitochondrial fusion were the key pathways. The changes of the related proteins carnitine palmitoyltransferase 1B, optic atrophy type 1, and mitofusin-1 were further verified by using western blot. The levels of these three proteins were upregulated in db/db mice, whereas this upregulation was attenuated by GCGR mAb treatment. CONCLUSION: GCGR antagonism has a protective effect on CMECs and cardiac diastolic function in diabetic mice, and this beneficial effect may be mediated via inhibiting fatty acid ß-oxidation and mitochondrial fusion in CMECs.


Asunto(s)
Diabetes Mellitus Experimental , Cardiomiopatías Diabéticas , Ratones , Animales , Receptores de Glucagón/metabolismo , Células Endoteliales , Cardiomiopatías Diabéticas/prevención & control , Cardiomiopatías Diabéticas/metabolismo , Dinámicas Mitocondriales , Proteómica , Anticuerpos Monoclonales/farmacología , Ácidos Grasos
7.
BMJ Open ; 13(5): e069080, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37192802

RESUMEN

INTRODUCTION: Recent cardiovascular outcomes trials have demonstrated that glucagon-like peptide 1 receptor agonist (GLP-1RA) decreases the incidence of major adverse cardiovascular events (MACEs) in individuals with type 2 diabetes mellitus (T2DM). Polyethylene glycol loxenatide (PEG-Loxe) is a once-weekly GLP-1RA obtained by modifying exendin-4. No clinical trials have been designed to assess the impact of PEG-Loxe on cardiovascular (CV) outcomes in individuals with T2DM. This trial aims to test the hypothesis that compared with placebo, PEG-Loxe treatment does not result in an unacceptable increase in CV risk in individuals with T2DM. METHODS AND ANALYSIS: This study is a multicentre, randomised, double-blind, placebo-controlled trial. Patients with T2DM who fulfilled the inclusion criteria were randomly divided to receive weekly administration of either PEG-Loxe 0.2 mg or placebo (1:1 ratio). The randomisation was stratified according to utilisation of sodium-glucose cotransporter 2 inhibitors, history of CV disease and body mass index. The research period is expected to be 3 years, with a 1-year recruitment period and a 2-year follow-up period. The primary outcome is the occurrence of the first MACE, described as CV death, non-fatal myocardial infarction or non-fatal stroke. The statistical analyses were undertaken on the intent-to-treat patient. The primary outcome was evaluated using a Cox proportional hazards model with treatment and randomisation strata as the covariates. ETHICS AND DISSEMINATION: The current research has been authorised by the Ethics Committee of Tianjin Medical University Chu Hsien-I Memorial Hospital (approval number: ZXYJNYYhMEC2022-2). Researchers must acquire informed consent from every participant before conducting any protocol-associated procedures. The findings of this study will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ChiCTR2200056410.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Infarto del Miocardio , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptidos/uso terapéutico , Polietilenglicoles/uso terapéutico , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/tratamiento farmacológico , Infarto del Miocardio/complicaciones , Método Doble Ciego , Resultado del Tratamiento , Hipoglucemiantes/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
8.
J Nutr Sci Vitaminol (Tokyo) ; 69(1): 1-6, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36858535

RESUMEN

Little is known about the impact of high-normal range of 25-hydroxyvitamin D [25(OH)D] on reproductive function. The aim of this study was to investigate the effect of different dose vitamin D supplementation in female mice on the pregnancy outcomes. Three groups of female mice were fed with fodder containing different dose of vitamin D at both pre-gestational and gestational stages. Serum 25(OH)D and calcium concentrations were monitored. The expression levels of vitamin D receptor (VDR) mRNA and protein in placenta were determined by real-time RT-PCR and western blot. Pregnancy outcomes were evaluated and compared among the three groups. Compared with the medium and low dose groups, serum 25(OH)D concentration was significantly increased and approximated to high-normal range in the high dose group (pre-gestational: 81.3±5.75 vs 52.8±6.24 and 25.0±3.99 ng/mL; gestational: 86.8±5.99 vs 52.6±9.29 and 27.9±4.96 ng/mL, respectively; all p<0.001). Interestingly, the average number of live fetuses per litter was much larger in the high dose group than in other two groups (19.8±5.31 vs 13.8±1.30 and 12.8±3.55 respectively, both p<0.05). However, no significant differences of the expression levels of VDR mRNA and protein in placenta were identified among the three groups. Supplementation of high dose vitamin D can enhance the female mice reproductive function. Further study is warranted to explore the mechanism by which high level of 25(OH)D in female mice increases the number of fetuses.


Asunto(s)
Fertilidad , Vitamina D , Vitaminas , Animales , Femenino , Ratones , Embarazo , Calcifediol , Feto , ARN Mensajero , Vitamina D/sangre , Resultado del Embarazo/veterinaria
9.
Diabetes Obes Metab ; 25 Suppl 1: 13-26, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36775938

RESUMEN

AIM: With industrialization and spread of the westernized lifestyle, the number of people affected by non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) is growing rapidly in China; this has become a major public health concern. To better understand the burden and characteristics of NAFLD/NASH in China, we aim to perform a narrative review of the literature published in this field. MATERIALS AND METHODS: We carried out a comprehensive electronic search of five English-language and three Chinese-language databases, to identify studies regarding NAFLD or NASH published from inception to November 30, 2022. Epidemiological studies of NAFLD/NASH in China were particularly noticed and summarized. We also searched the www. CLINICALTRIALS: gov and www.chictr.org.cn websites for the registered trials on the treatment of the disease led by Chinese investigators or located in China. RESULTS: The increasing rate of NAFLD prevalence in China is strikingly high, reaching more than twice that in western countries. The prevalence of NAFLD is nearly 30% of the general Chinese population, making it the leading cause of chronic liver diseases. The prevalence of NAFLD/NASH varies between provinces/regions, age groups, sexes, and individuals with different metabolic profiles. NAFLD co-exists in many Chinese patients with chronic hepatitis B. Since 2020, more Chinese studies have used the term metabolic-associated fatty liver disease (MAFLD), emphasizing the underlying metabolic disorders that occur concurrently with this disease. Several clinical trials involving lifestyle interventions, antidiabetic drugs, or traditional Chinese medicines, registered by Chinese investigators, have been completed or are ongoing. Moreover, several innovative targeted therapies developed in China are revolutionizing the treatment of NAFLD/NASH. CONCLUSIONS: NAFLD has cast a heavy burden on the Chinese healthcare system. Chinese scholars are making efforts to achieve the optimal management of this disease.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/terapia , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Hipoglucemiantes/uso terapéutico , China/epidemiología
10.
Diabetes ; 72(5): 599-610, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36826938

RESUMEN

Dysfunction of glucagon-secreting α-cells participates in the progression of diabetes, and glucagon receptor (GCGR) antagonism is regarded as a novel strategy for diabetes therapy. GCGR antagonism upregulates glucagon and glucagon-like peptide 1 (GLP-1) secretion and, notably, promotes ß-cell regeneration in diabetic mice. Here, we aimed to clarify the role of GLP-1 receptor (GLP-1R) activated by glucagon and/or GLP-1 in the GCGR antagonism-induced ß-cell regeneration. We showed that in db/db mice and type 1 diabetic wild-type or Flox/cre mice, GCGR monoclonal antibody (mAb) improved glucose control, upregulated plasma insulin level, and increased ß-cell area. Notably, blockage of systemic or pancreatic GLP-1R signaling by exendin 9-39 (Ex9) or Glp1r knockout diminished the above effects of GCGR mAb. Furthermore, glucagon-neutralizing antibody (nAb), which prevents activation of GLP-1R by glucagon, also attenuated the GCGR mAb-induced insulinotropic effect and ß-cell regeneration. In cultured primary mouse islets isolated from normal mice and db/db mice, GCGR mAb action to increase insulin release and to upregulate ß-cell-specific marker expression was reduced by a glucagon nAb, by the GLP-1R antagonist Ex9, or by a pancreas-specific Glp1r knockout. These findings suggest that activation of GLP-1R by glucagon participates in ß-cell regeneration induced by GCGR antagonism in diabetic mice. ARTICLE HIGHLIGHTS: Glucagon receptor (GCGR) antagonism promotes ß-cell regeneration in type 1 and type 2 diabetic mice and in euglycemic nonhuman primates. Glucagon and glucagon-like peptide 1 (GLP-1) can activate the GLP-1 receptor (GLP-1R), and their levels are upregulated following GCGR antagonism. We investigated whether GLP-1R activated by glucagon and/or GLP-1 contributed to ß-cell regeneration induced by GCGR antagonism. We found that blockage of glucagon-GLP-1R signaling attenuated the GCGR monoclonal antibody-induced insulinotropic effect and ß-cell regeneration in diabetic mice. Our study reveals a novel mechanism of ß-cell regeneration and uncovers the communication between α-cells and ß-cells in regulating ß-cell mass.


Asunto(s)
Diabetes Mellitus Experimental , Células Secretoras de Glucagón , Ratones , Animales , Glucagón/metabolismo , Receptores de Glucagón/genética , Receptor del Péptido 1 Similar al Glucagón/genética , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Diabetes Mellitus Experimental/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Insulina/metabolismo , Células Secretoras de Glucagón/metabolismo , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/metabolismo , Regeneración
11.
Diabetes Metab Res Rev ; 39(3): e3607, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36565185

RESUMEN

AIMS: Sodium-glucose co-transporter 2 inhibitors, including dapagliflozin, improve ß cell function in type 2 diabetic individuals. Whether dapagliflozin can protect islet microvascular endothelial cells (IMECs) and thus contribute to the improvement of ß cell function remains unknown. MATERIALS AND METHODS: The db/db mice were treated with dapagliflozin or vehicle for 6 weeks. ß cell function, islet capillaries and the levels of inflammatory chemokines in IMECs were detected. The mouse IMEC cell line MS-1 cells were incubated with palmitate and/or dapagliflozin for 24 h. Angiogenesis and inflammatory chemokine levels were evaluated, and the involved signalling pathways were analysed. The mouse ß cell line MIN6 cells, in the presence or absence of co-culture with MS-1 cells, were treated with palmitate and/or dapagliflozin for 24 h. The expression of ß cell specific markers and insulin secretion in MIN6 cells were determined. RESULTS: Dapagliflozin significantly improved ß cell function, increased islet capillaries and decreased the levels of inflammatory chemokines of IMECs in db/db mice. In the palmitate-treated MS-1 cells, angiogenesis was enhanced and the levels of inflammatory chemokines were downregulated by dapagliflozin. Either a PI3K inhibitor or mTOR inhibitor eliminated the dapagliflozin-mediated effects. Importantly, dapagliflozin attenuated the palmitate-induced downregulation of ß cell function-related gene expression and insulin secretion in MIN6 cells co-cultured with MS-1 cells but not in those on mono-culture. CONCLUSIONS: Dapagliflozin restores islet vascularisation and attenuates the inflammation of IMECs in type 2 diabetic mice. The dapagliflozin-induced improvement of ß cell function is at least partially accounted for by its beneficial effects on IMECs in a PI3K/Akt-mTOR-dependent manner.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Islotes Pancreáticos , Enfermedades Vasculares , Ratones , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Células Endoteliales , Fosfatidilinositol 3-Quinasas/metabolismo , Islotes Pancreáticos/metabolismo , Compuestos de Bencidrilo/farmacología , Enfermedades Vasculares/metabolismo , Palmitatos/metabolismo
12.
Diabetologia ; 66(3): 535-550, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36331598

RESUMEN

AIMS/HYPOTHESIS: Glucagon receptor (GCGR) antagonism ameliorates hyperglycaemia and promotes beta cell regeneration in mouse models of type 2 diabetes. However, the underlying mechanisms remain unclear. The present study aimed to investigate the mechanism of beta cell regeneration induced by GCGR antagonism in mice. METHODS: The db/db mice and high-fat diet (HFD)+streptozotocin (STZ)-induced mice with type 2 diabetes were treated with antagonistic GCGR monoclonal antibody (mAb), and the metabolic variables and islet cell quantification were evaluated. Plasma cytokine array and liver RNA sequencing data were used to screen possible mediators, including fibroblast growth factor 21 (FGF21). ELISA, quantitative RT-PCR and western blot were applied to verify FGF21 change. Blockage of FGF21 signalling by FGF21-neutralising antibody (nAb) was used to clarify whether FGF21 was involved in the effects of GCGR mAb on the expression of beta cell identity-related genes under plasma-conditional culture and hepatocyte co-culture conditions. FGF21 nAb-treated db/db mice, systemic Fgf21-knockout (Fgf21-/-) diabetic mice and hepatocyte-specific Fgf21-knockout (Fgf21Hep-/-) diabetic mice were used to reveal the involvement of FGF21 in beta cell regeneration. A BrdU tracing study was used to analyse beta cell proliferation in diabetic mice treated with GCGR mAb. RESULTS: GCGR mAb treatment improved blood glucose control, and increased islet number (db/db 1.6±0.1 vs 0.8±0.1 per mm2, p<0.001; HFD+STZ 1.2±0.1 vs 0.5±0.1 per mm2, p<0.01) and area (db/db 2.5±0.2 vs 1.2±0.2%, p<0.001; HFD+STZ 1.0±0.1 vs 0.3±0.1%, p<0.01) in diabetic mice. The plasma cytokine array and liver RNA sequencing data showed that FGF21 levels in plasma and liver were upregulated by GCGR antagonism. The GCGR mAb induced upregulation of plasma FGF21 levels (db/db 661.5±40.0 vs 466.2±55.7 pg/ml, p<0.05; HFD+STZ 877.0±106.8 vs 445.5±54.0 pg/ml, p<0.05) and the liver levels of Fgf21 mRNA (db/db 3.2±0.5 vs 1.8±0.1, p<0.05; HFD+STZ 2.0±0.3 vs 1.0±0.2, p<0.05) and protein (db/db 2.0±0.2 vs 1.4±0.1, p<0.05; HFD+STZ 1.6±0.1 vs 1.0±0.1, p<0.01). Exposure to plasma or hepatocytes from the GCGR mAb-treated mice upregulated the mRNA levels of characteristic genes associated with beta cell identity in cultured mouse islets and a beta cell line, and blockage of FGF21 activity by an FGF21 nAb diminished this upregulation. Notably, the effects of increased beta cell number induced by GCGR mAb were attenuated in FGF21 nAb-treated db/db mice, Fgf21-/- diabetic mice and Fgf21Hep-/- diabetic mice. Moreover, GCGR mAb treatment enhanced beta cell proliferation in the two groups of diabetic mice, and this effect was weakened in Fgf21-/- and Fgf21Hep-/- mice. CONCLUSIONS/INTERPRETATION: Our findings demonstrate that liver-derived FGF21 is involved in the GCGR antagonism-induced beta cell regeneration in a mouse model of type 2 diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Células Secretoras de Glucagón , Ratones , Animales , Glucagón/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Glucagón/metabolismo , Diabetes Mellitus Experimental/metabolismo , Receptores de Glucagón/genética , Modelos Animales de Enfermedad , Hígado/metabolismo , Citocinas/metabolismo , Ratones Endogámicos C57BL
13.
Am J Physiol Endocrinol Metab ; 324(1): E97-E113, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36383639

RESUMEN

Glucagon-secreting pancreatic α-cells play pivotal roles in the development of diabetes. Glucagon promotes insulin secretion from ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells had remained elusive. In this study, we found that long-term glucagon intervention or glucagon intervention with the presence of palmitic acid downregulated ß-cell-specific markers and inhibited insulin secretion in cultured ß-cells. These results suggested that glucagon induced ß-cell dedifferentiation under pathological conditions. Glucagon blockage by a glucagon receptor (GCGR) monoclonal antibody (mAb) attenuated glucagon-induced ß-cell dedifferentiation. In primary islets, GCGR mAb treatment upregulated ß-cell-specific markers and increased insulin content, suggesting that blockage of endogenous glucagon-GCGR signaling inhibited ß-cell dedifferentiation. To investigate the possible mechanism, we found that glucagon decreased FoxO1 expression. FoxO1 inhibitor mimicked the effect of glucagon, whereas FoxO1 overexpression reversed the glucagon-induced ß-cell dedifferentiation. In db/db mice and ß-cell lineage-tracing diabetic mice, GCGR mAb lowered glucose level, upregulated plasma insulin level, increased ß-cell area, and inhibited ß-cell dedifferentiation. In aged ß-cell-specific FoxO1 knockout mice (with the blood glucose level elevated as a diabetic model), the glucose-lowering effect of GCGR mAb was attenuated and the plasma insulin level, ß-cell area, and ß-cell dedifferentiation were not affected by GCGR mAb. Our results proved that glucagon induced ß-cell dedifferentiation under pathological conditions, and the effect was partially mediated by FoxO1. Our study reveals a novel cross talk between α- and ß-cells and is helpful to understand the pathophysiology of diabetes and discover new targets for diabetes treatment.NEW & NOTEWORTHY Glucagon-secreting pancreatic α-cells can interact with ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells has remained elusive. Our new finding shows that long-term glucagon induces ß-cell dedifferentiation in cultured ß-cells. FoxO1 inhibitor mimicks whereas glucagon signaling blockage by GCGR mAb reverses the effect of glucagon. In type 2 diabetic mice, GCGR mAb increases ß-cell area, improves ß-cell function, and inhibits ß-cell dedifferentiation, and the effect is partially mediated by FoxO1.


Asunto(s)
Diabetes Mellitus Experimental , Insulinas , Ratones , Animales , Receptores de Glucagón/metabolismo , Glucagón/metabolismo , Glucemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Desdiferenciación Celular , Ratones Noqueados , Insulina/metabolismo , Proteína Forkhead Box O1
14.
Acta Diabetol ; 60(1): 19-28, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36129525

RESUMEN

AIMS: To investigate whether treatment with γ-aminobutyric acid (GABA) alone or in combination with glucagon receptor (GCGR) monoclonal antibody (mAb) exerted beneficial effects on ß-cell mass and α-cell mass, and to explore the origins of the regenerated ß-cells in mice with type 1 diabetes (T1D). METHODS: Streptozotocin (STZ)-induced T1D mice were treated with intraperitoneal injection of GABA (250 µg/kg per day) and/or REMD 2.59 (a GCGR mAb, 5 mg/kg per week), or IgG dissolved in PBS for 8 weeks. Plasma hormone levels and islet cell morphology were evaluated by ELISA and immunofluorescence, respectively. The origins of the regenerated ß-cells were analyzed by double-immunostaining, α-cell lineage-tracing and BrdU-tracing studies. RESULTS: After the 8-week treatment, GABA or GCGR mAb alone or in combination ameliorated hyperglycemia in STZ-induced T1D mice. GCGR mAb upregulated plasma insulin level and increased ß-cell mass, and GABA appeared to have similar effects in T1D mice. However, combination treatment did not reveal any additive or synergistic effect. Interestingly, the GCGR mAb-induced increment of plasma glucagon level and α-cell mass was attenuated by the combined treatment of GABA. In addition, duct-derived ß-cell neogenesis and α-to-ß cell conversion but not ß-cell proliferation contributed to the increased ß-cell mass in T1D mice. CONCLUSION: These results suggested that GABA attenuated α-cell hyperplasia but did not potentiates ß-cell regeneration induced by GCGR mAb in T1D mice. Our findings provide novel insights into a combination treatment strategy for ß-cell regeneration in T1D.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Animales , Ratones , Receptores de Glucagón , Glucagón , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Experimental/tratamiento farmacológico , Hiperplasia , Ácido gamma-Aminobutírico/farmacología , Regeneración , Insulina/farmacología , Glucemia
15.
Diabetes Ther ; 13(10): 1755-1767, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35963931

RESUMEN

INTRODUCTION: We aimed to investigate whether treatment with exenatide could increase time in range (TIR) and decrease glycemic variability, and to evaluate the association between TIR and endothelial injury in patients with type 2 diabetes mellitus (T2DM). METHODS: Two-hundred patients with T2DM treated with exenatide for 16 weeks were included in this study. Seven-point fingerstick blood glucose was used to evaluate derived TIR and glycemic variability. The serum levels of soluble endothelial cell protein C receptor (sEPCR) and von Willebrand factor (vWF) were measured. Ninety-three patients having the data of endothelial injury markers were categorized as derived TIR > 70% or ≤ 70% after the treatment and the association between TIR and endothelial injury were evaluated. RESULTS: Treatment with exenatide for 16 weeks resulted in a significant reduction in fasting blood glucose, postprandial 2 h blood glucose, and glycated hemoglobin A1c (HbA1c) levels in patients with T2DM. Compared with baseline, derived TIR value was significantly increased [85.7 (57.1, 100.0) % vs. 42.9 (14.9, 71.4) %, P < 0.001], and the parameters of glycemic variability were remarkably decreased after the treatment. After the treatment, serum sEPCR level was significantly decreased from baseline in patients with TIR > 70% [74.5 (32.8, 122.5) ng/mL vs. 96.9 (48.5, 150.9) ng/mL, P = 0.006] but not in those with TIR ≤ 70%; serum vWF level was remarkably decreased in patients with TIR > 70% [from 1166.2 (848.1, 1335.5) mIU/mL to 907.4 (674.3, 1335.1) mIU/mL, P = 0.001] while this effect was modest in those with TIR ≤ 70%. CONCLUSIONS: Treatment with exenatide increases TIR and decreases glycemic variability in patients with T2DM. Moreover, the amelioration of endothelial injury is more pronounced in patients with TIR > 70% after the treatment. TRIAL REGISTRATION: ChiCTR-IPR-15006558 (registered, 27 May 2015).

16.
iScience ; 25(7): 104567, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35789836

RESUMEN

The deficiency of pancreatic ß-cells is the key pathogenesis of diabetes, while glucagon-secreting α-cells are another player in the development of diabetes. Here, we aimed to investigate the effects of glucagon receptor (GCGR) antagonism on ß-cell neogenesis in type 2 diabetic (T2D) mice and explore the origins of the neogenic ß-cells. We showed that GCGR monoclonal antibody (mAb) elevated plasma insulin level and increased ß-cell mass in T2D mice. By using α-cell lineage-tracing (glucagon -cre -ß-gal) mice and inducible Ngn3+ pancreatic endocrine progenitor lineage-tracing (Ngn3-CreERT2-tdTomato) mice, we found that GCGR mAb treatment promoted α-cell regression to progenitors, and induced Ngn3+ progenitor reactivation and differentiation toward ß-cells. Besides, GCGR mAb upregulated the expression levels of ß-cell regeneration-associated genes and promoted insulin secretion in primary mouse islets, indicative of a direct effect on ß-cell identity. Our findings suggest that GCGR antagonism not only increases insulin secretion but also promotes pro-α-cell-derived ß-cell neogenesis in T2D mice.

17.
J Evid Based Med ; 15(2): 168-179, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35715995

RESUMEN

Since it is difficult for clinicians to make a decision among the various types of antidiabetic medications due to their great discrepancy in mechanisms, pharmacological properties, and cardiovascular/renal protection, a relatively "precision" or personalized hypoglycemic treatment suggestion is practical for type 2 diabetes (T2D) management in adults. This expert consensus makes some recommendations based on the characteristics of adult T2D patients without clinical cardiovascular disease (CVD) or chronic kidney disease (CKD) by evidence from large-scale clinical trials. The main consideration for initiating antidiabetic medications is the safety and benefits for prevention of target organ damage, such as CVD and CKD. The choice of personalized glucose-lowering therapy regarding target organ protection is based on the various effects of antidiabetic medications, patients' clinical characteristics and their key risks, as well as the sociological factors. According to the effects on glucose reduction, cardiovascular protection, renal benefit, body weight change, hypoglycemic risk, and liver function impact, the antidiabetic medications are recategorized in this consensus. Combined with the glucose control target and the different effects of hypoglycemic agents, a significant body of recommendations have been developed for optimal T2D management according to the risk factors for atherosclerotic CVD, heart failure, CKD, primary fatty liver, and hypoglycemia. This consensus gives detailed guidance on personalized antidiabetic therapy initiation in newly diagnosed T2D adults, which attaches great importance to both glucose control and target organ protection.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Insuficiencia Renal Crónica , Glucemia , Consenso , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucosa/uso terapéutico , Humanos , Hipoglucemiantes/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico
19.
Diabetes Ther ; 13(5): 969-981, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35312971

RESUMEN

INTRODUCTION: Cardiovascular disease (CVD) is the leading cause of death in Chinese adults with type 2 diabetes (T2D), and treatment guidelines have increasingly focused on the comprehensive management of T2D and CVD. Here, we report data from the Chinese population within the CAPTURE study, including CVD prevalence in patients with T2D and insights into their management. METHODS: CAPTURE (a multinational, non-interventional, cross-sectional study in adults with T2D) included data from eight centers in China from July to September 2019. Overall CVD prevalence estimates were calculated, and descriptive data regarding CVD subtypes and treatment were collected and reported here. RESULTS: Of 805 adults with T2D enrolled in China (61.9% male, median age 59 years), 273 had established CVD, with an estimated prevalence (95% CI) of 33.9% (30.6%, 37.3%). Most CVD cases were atherosclerotic (94.9%). Coronary heart disease had the highest estimated prevalence (16.0%), followed by carotid artery disease (9.6%) and cerebrovascular disease (7.7%). Use of glucose-lowering agents (GLAs) with proven cardiovascular benefits (glucagon-like peptide-1 receptor agonists and/or sodium-glucose cotransporter-2 inhibitors) was low in the China sample (7.7%). Approximately half of the CVD subgroup in the China sample was receiving cardiovascular medication, but use of guideline-directed agents was low (e.g., statins: 35.9%; angiotensin II receptor blockers: 15%; angiotensin-converting enzyme inhibitors: 2.6%). CONCLUSIONS: In the Chinese CAPTURE population, one-third of patients had established CVD, with atherosclerotic CVD largely accounting for the CVD burden; use of GLAs with proven cardiovascular benefits and cardiovascular medications was low, suggesting an unmet need for optimal management in this group.

20.
Diabetes Ther ; 13(1): 161-173, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34870792

RESUMEN

INTRODUCTION: We evaluated the effect of dulaglutide on the relative contributions of fasting glucose (FG) and postprandial glucose (PPG) to overall hyperglycemia in patients with type 2 diabetes (T2D), and assessed responses to dulaglutide versus insulin glargine (glargine) in patients with different baseline glycemic patterns. METHODS: This post-hoc analysis of the phase 3 AWARD-CHN2 trial included data from 560 Chinese patients with uncontrolled T2D who received once-weekly dulaglutide (1.5 or 0.75 mg) or once-daily glargine for 26 weeks. The relative contributions of FG and PPG to overall hyperglycemia across different glycated hemoglobin (HbA1c) categories were calculated using the area under the curve of 7-point self-monitored blood glucose profiles. Patients were also categorized into four subgroups according to median baseline FG (cutoff 8.9 mmol/L) and PPG (cutoff 12.5 mmol/L): low FG/low PPG, low FG/high PPG, high FG/low PPG and high FG/high PPG. Changes in glycemic parameters and body weight were calculated for patients in each subgroup. RESULTS: Among patients receiving dulaglutide, higher HbA1c was associated with higher relative contributions of FG and lower relative contributions of PPG to overall hyperglycemia at baseline and week 26 of dulaglutide treatment. After 26 weeks, dulaglutide 1.5 mg led to statistically greater decreases in HbA1c from baseline versus glargine in most subgroups, including the high FG subgroups, and a numerically greater decrease in HbA1c was observed in the low FG/high PPG subgroup. Across all subgroups, higher proportions of patients achieved HbA1c ≤ 6.5% with dulaglutide 1.5 mg than with glargine (all P < 0.05). Dulaglutide 1.5 mg showed better control of body weight than glargine in all subgroups (all P < 0.05). CONCLUSIONS: Dulaglutide reduced HbA1c through reductions in both FG and PPG across HbA1c categories in T2D patients with uncontrolled hyperglycemia. Furthermore, treatment with dulaglutide provided a greater reduction in HbA1c than glargine, regardless of baseline FG and PPG levels.

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