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1.
Diabetes ; 73(6): 926-940, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38471012

ABSTRACT

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.


Subject(s)
Benzhydryl Compounds , Gastrointestinal Microbiome , Glucagon-Like Peptide 1 , Glucosides , Insulin-Secreting Cells , Regeneration , Tryptophan , Animals , Benzhydryl Compounds/pharmacology , Insulin-Secreting Cells/metabolism , Insulin-Secreting Cells/drug effects , Glucagon-Like Peptide 1/metabolism , Gastrointestinal Microbiome/drug effects , Gastrointestinal Microbiome/physiology , Tryptophan/metabolism , Mice , Glucosides/pharmacology , Glucosides/therapeutic use , Regeneration/drug effects , Humans , Male , Insulin/metabolism , Blood Glucose/metabolism , Blood Glucose/drug effects , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/microbiology , Mice, Inbred C57BL , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Diabetes Mellitus, Experimental/metabolism , Glucagon-Like Peptide-1 Receptor/metabolism
2.
Diabetologia ; 66(3): 535-550, 2023 03.
Article in English | MEDLINE | ID: mdl-36331598

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Glucagon-Secreting Cells , Mice , Animals , Glucagon/metabolism , Diabetes Mellitus, Type 2/metabolism , Glucagon-Secreting Cells/metabolism , Diabetes Mellitus, Experimental/metabolism , Receptors, Glucagon/genetics , Disease Models, Animal , Liver/metabolism , Cytokines/metabolism , Mice, Inbred C57BL
3.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-993163

ABSTRACT

Objective:To compare the effect of neoadjuvant chemotherapy vs. concurrent chemoradiotherapy on the target volume and organs at risk for locally advanced bulky (>4 cm) cervical cancer. Methods:From March 1, 2019 to June 30, 2021, 146 patients pathologically diagnosed with cervical cancer were selected and randomly divided into two groups using random number table method: the neoadjuvant chemotherapy (NACT) + concurrent chemoradiotherapy (CCRT) group ( n=73) and CCRT group ( n=73). Patients in the NACT+CCRT group received 2 cycles of paclitaxel combined with cisplatin NACT, followed by CCRT, the chemotherapy regimen was the same as NACT. In the CCRT group, CCRT was given. Statistical description of categorical data was expressed by rate. The measurement data between two groups were compared by Wilcoxon rank-sum test for comparison of two independent samples, and the rate or composition ratio of two groups was compared by χ2 test. Results:Before radiotherapy, GTV in the NACT+CCRT group was (31.95±25.96) cm 3, significantly lower than (71.54±33.59) cm 3 in the CCRT group ( P<0.01). Besides, CTV and PTV in the NACT+CCRT group were also significantly lower compared with those in the CCRT group (both P<0.05). In terms of target volume dosimetry, D 100GTV, D 95CTV, V 100GTV, V 100CTV and V 95PTV in the NACT+CCRT group were significantly higher than those in the CCRT group (all P<0.05). The complete remision (CR) rates in the NACT+CCRT and CCRT groups were 86.3% and 67.6%, with statistical significance between two groups ( P<0.01) . Regarding organs at risk, NACT+CCRT group significantly reduced the dose to the bladder, rectum, small intestine and urethra compared with CCRT group (all P<0.05). Conclusions:NACT can reduce the volume of tumors in patients with large cervical masses, increase the radiation dose to tumors, reduce the dose to organs at risk, and make the three-dimensional brachytherapy easier. Therefore, NACT combined with CCRT may be a new choice for patients with locally advanced cervical cancer with large masses.

4.
iScience ; 25(7): 104567, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35789836

ABSTRACT

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.

5.
Endocr Res ; 46(4): 170-177, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34014139

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) is a severe infectious illness. It has been reported that COVID-19 has an effect on thyroid function. However, the association between thyroid function and prognosis of COVID-19 is still unclear.Methods: This retrospective study included patients with COVID-19 admitted to Tongji Hospital in Wuhan from January 28 to April 4, 2020. Demographic, epidemiological, clinical, laboratory, treatment, and outcome data were collected from patients with laboratory-confirmed COVID-19. Patients without history of thyroid disease who had a thyroid function test at admission were enrolled in the final analysis. Risk factors of in-hospital death were explored using univariable and multivariable Cox regression analyses. Survival differences were assessed with Kaplan-Meier curves and log-rank test.Results: A total of 127 patients were included in this study, with 116 survivors and 11 non-survivors. The serum levels of thyroid stimulating hormone (TSH) [0.8 (0.5-1.7) vs. 1.9 (1.0-3.1) µIU/mL, P = .031] and free triiodothyronine (FT3) [2.9 (2.8-3.1) vs. 4.2 (3.5-4.7) pmol/L, P < .001] were lower in non-survivors than in survivors, and a low FT3 state (defined as FT3 < 3.1 pmol/L) at admission accounted for a higher proportion in non-survivors than in survivors (72.7% vs. 11.2%, P < .001). Univariate Cox regression analysis showed that FT3 level (HR 0.213, 95% CI: 0.101-0.451, P < .001) and the low FT3 state (HR 14.607, 95% CI: 3.873-55.081, P < .001) were negatively and positively associated with the risk of in-hospital death, respectively. Furthermore, multivariate Cox regression analysis revealed that a low FT3 state was associated with an increased risk of in-hospital death after adjusting for confounding factors (HR 13.288, 95% CI: 1.089-162.110, P = .043). Moreover, Kaplan-Meier curves indicated a lower survival probability in COVID-19 patients with a low FT3 status.Conclusion: Serum FT3 level is lower in non-survivors among moderate-to-critical patients with COVID-19, and the low FT3 state is associated with an increased risk of in-hospital mortality of COVID-19.


Subject(s)
COVID-19/mortality , COVID-19/physiopathology , Prognosis , SARS-CoV-2 , Thyroid Gland/physiopathology , Aged , COVID-19/epidemiology , China/epidemiology , Female , Hospital Mortality , Humans , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Factors , Thyrotropin/blood , Thyroxine/blood , Triiodothyronine/blood
6.
Metabolism ; 111: 154324, 2020 10.
Article in English | MEDLINE | ID: mdl-32712220

ABSTRACT

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


Subject(s)
Benzhydryl Compounds/pharmacology , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/metabolism , Endocrine Cells/drug effects , Glucagon-Secreting Cells/drug effects , Glucosides/pharmacology , Regeneration/drug effects , Animals , Blood Glucose/metabolism , C-Peptide/metabolism , Disease Models, Animal , Endocrine Cells/metabolism , Glucagon/metabolism , Glucagon-Like Peptide 1/metabolism , Glucagon-Like Peptide-1 Receptor/metabolism , Glucagon-Secreting Cells/metabolism , Glucose/metabolism , Insulin/metabolism , Insulin-Secreting Cells/metabolism , Male , Mice , Proprotein Convertase 1/metabolism , Sodium-Glucose Transporter 2 Inhibitors
7.
Peptides ; 131: 170349, 2020 09.
Article in English | MEDLINE | ID: mdl-32561493

ABSTRACT

Glucagon is an essential regulator of glucose homeostasis, particularly in type 2 diabetes (T2D). Blocking the glucagon receptor (GCGR) in diabetic animals and humans has been shown to alleviate hyperglycemia and increase circulating glucagon-like peptide-1 (GLP-1) levels. However, the origin of the upregulated GLP-1 remains to be clarified. Here, we administered high-fat diet + streptozotocin-induced T2D mice and diabetic db/db mice with REMD 2.59, a fully competitive antagonistic human GCGR monoclonal antibody (mAb) for 12 weeks. GCGR mAb treatment decreased fasting blood glucose levels and increased plasma GLP-1 levels in the T2D mice. In addition, GCGR mAb upregulated preproglucagon gene expression and the contents of gut proglucagon-derived peptides, particularly GLP-1, in the small intestine and colon. Notably, T2D mice treated with GCGR mAb displayed a higher L-cell density in the small intestine and colon, which was associated with increased numbers of LK-cells coexpressing GLP-1 and glucose-dependent insulinotropic polypeptide and reduced L-cell apoptosis. Furthermore, GCGR mAb treatment upregulated GLP-1 production in the pancreas, which was detected at lower levels than in the intestine. Collectively, these results suggest that GCGR mAb can increase intestinal GLP-1 production and L-cell number by enhancing LK-cell expansion and inhibiting L-cell apoptosis in T2D.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antibodies, Neutralizing/pharmacology , Diabetes Mellitus, Experimental/drug therapy , Gastric Inhibitory Polypeptide/genetics , Glucagon-Like Peptide 1/genetics , Receptors, Glucagon/genetics , Animals , Apoptosis/genetics , Blood Glucose/metabolism , Colon/drug effects , Colon/metabolism , Diabetes Mellitus, Experimental/etiology , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/metabolism , Diet, High-Fat/adverse effects , Fasting/metabolism , Gastric Inhibitory Polypeptide/metabolism , Gene Expression Regulation , Glucagon-Like Peptide 1/metabolism , Humans , Intestine, Small/drug effects , Intestine, Small/metabolism , Male , Mice , Mice, Inbred C57BL , Pancreas/drug effects , Pancreas/metabolism , Proglucagon/genetics , Proglucagon/metabolism , Receptors, Glucagon/antagonists & inhibitors , Receptors, Glucagon/metabolism , Signal Transduction , Streptozocin/administration & dosage
8.
Article in English | MEDLINE | ID: mdl-32139602

ABSTRACT

OBJECTIVE: Glucagon receptor (GCGR) blockage improves glycemic control and increases circulating glucagon-like peptide-1 (GLP-1) level in diabetic animals and humans. The elevated GLP-1 has been reported to be involved in the hypoglycemic effect of GCGR blockage. However, the source of this elevation remains to be clarified. RESEARCH DESIGN AND METHODS: REMD 2.59, a human GCGR monoclonal antibody (mAb), was administrated for 12 weeks in db/db mice and high-fat diet+streptozotocin (HFD/STZ)-induced type 2 diabetic (T2D) mice. Blood glucose, glucose tolerance and plasma GLP-1 were evaluated during the treatment. The gut length, epithelial area, and L-cell number and proliferation were detected after the mice were sacrificed. Cell proliferation and GLP-1 production were measured in mouse L-cell line GLUTag cells, and primary mouse and human enterocytes. Moreover, GLP-1 receptor (GLP-1R) antagonist or protein kinase A (PKA) inhibitor was used in GLUTag cells to determine the involved signaling pathways. RESULTS: Treatment with the GCGR mAb lowered blood glucose level, improved glucose tolerance and elevated plasma GLP-1 level in both db/db and HFD/STZ-induced T2D mice. Besides, the treatment promoted L-cell proliferation and LK-cell expansion, and increased the gut length, epithelial area and L-cell number in these two T2D mice. Similarly, our in vitro study showed that the GCGR mAb promoted L-cell proliferation and increased GLP-1 production in GLUTag cells, and primary mouse and human enterocytes. Furthermore, either GLP-1R antagonist or PKA inhibitor diminished the effects of GCGR mAb on L-cell proliferation and GLP-1 production. CONCLUSIONS: The elevated circulating GLP-1 level by GCGR mAb is mainly due to intestinal L-cell proliferation and GLP-1 production, which may be mediated via GLP-1R/PKA signaling pathways. Therefore, GCGR mAb represents a promising strategy to improve glycemic control and restore the impaired GLP-1 production in T2D.


Subject(s)
Diabetes Mellitus, Type 2/blood , Glucagon-Like Peptide 1/blood , Ileum/metabolism , Receptors, Glucagon/metabolism , Animals , Antibodies, Monoclonal/administration & dosage , Cell Proliferation/drug effects , Diabetes Mellitus, Experimental/blood , Ileum/drug effects , L Cells , Male , Mice , Mice, Inbred C57BL , Proglucagon/metabolism , Receptors, Glucagon/antagonists & inhibitors , Receptors, Glucagon/immunology , Signal Transduction
9.
Peptides ; 124: 170212, 2020 02.
Article in English | MEDLINE | ID: mdl-31770577

ABSTRACT

In type 2 diabetes, lipotoxicity damages islet microvascular endothelial cells (IMECs), leading to pancreatic islet ß cell dysfunction directly or indirectly. Glucagon-like peptide-1 (GLP-1) and its analogs have beneficial roles in endothelial cells. However, the protective effects of GLP-1 agents on IMECs and their potential mechanism remained obscure. In this study, exposure of MS-1 (a cell line derived from mouse IMECs) to different concentrations of palmitic acid (PA) was used to establish an injury model. The cells exposed to PA (0.25 mmol/L) were treated with a GLP-1 analog liraglutide (3, 10, 30, and 100 nmol/L). Reactive oxygen species (ROS) generation, apoptosis-related protein level, and endothelin-1 production were detected. The protein levels of signaling molecules were analyzed and specific inhibitors or blockers were used to identify involvement of signaling pathways in the effects of liraglutide. Results showed that PA significantly increased ROS generation and the levels of pro-apoptotic protein Bax, and decreased the levels of anti-apoptotic protein Bcl-2 and the mRNA expression and secretion of endothelin-1. Meanwhile, PA downregulated the protein levels of GLP-1 receptor (GLP-1R), phosphorylated protein kinase A (PKA), guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1), and endothelial nitric oxide synthase (eNOS). Furthermore, liraglutide ameliorated all these effects of PA in a dose-dependent manner. Importantly, GLP-1R antagonist exendin (9-39), PKA inhibitor H89, GTPCH1 inhibitor 2,4-diamino-6-hydroxypyrimidine, or NOS inhibitor N-nitro-l-arginine-methyl ester abolished the liraglutide-mediated amelioration in PA-impaired MS-1 cells. In conclusion, liraglutide ameliorates the PA-induced oxidative stress, apoptosis, and endothelin-1 secretion dysfunction in mouse IMECs through GLP-1R/PKA and GTPCH1/eNOS signaling pathways.


Subject(s)
Glucagon-Like Peptide-1 Receptor/metabolism , Islets of Langerhans/drug effects , Liraglutide/pharmacology , Nitric Oxide Synthase Type III/metabolism , Palmitates/toxicity , Animals , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/metabolism , Endothelin-1/metabolism , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , GTP Cyclohydrolase/metabolism , Islets of Langerhans/cytology , Islets of Langerhans/metabolism , Islets of Langerhans/pathology , Isoquinolines/pharmacology , Mice , Oxidative Stress/drug effects , Peptide Fragments/pharmacology , Protective Agents/pharmacology , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Sulfonamides/pharmacology , bcl-2-Associated X Protein/metabolism
10.
iScience ; 16: 326-339, 2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31203188

ABSTRACT

Under extreme conditions or by genetic modification, pancreatic α-cells can regenerate and be converted into ß-cells. This regeneration holds substantial promise for cell replacement therapy in diabetic patients. The discovery of clinical therapeutic strategies to promote ß-cell regeneration is crucial for translating these findings into clinical applications. In this study, we reported that treatment with REMD 2.59, a human glucagon receptor (GCGR) monoclonal antibody (mAb), lowered blood glucose without inducing hypoglycemia in normoglycemic, streptozotocin-induced type 1 diabetic (T1D) and non-obesity diabetic mice. Moreover, GCGR mAb treatment increased the plasma glucagon and active glucagon-like peptide-1 levels, induced pancreatic ductal ontogenic α-cell neogenesis, and promoted α-cell proliferation. Strikingly, the treatment also increased the ß-cell mass in these two T1D models. Using α-cell lineage-tracing mice, we found that the neogenic ß-cells were likely derived from α-cell conversion. Therefore, GCGR mAb-induced α- to ß-cell conversion might represent a pre-clinical approach for improving diabetes therapy.

11.
Biochem Biophys Res Commun ; 512(4): 864-870, 2019 05 14.
Article in English | MEDLINE | ID: mdl-30929915

ABSTRACT

Pancreatic δ-cells, which produce somatostatin, play an indispensable role in glucose homeostasis by inhibiting glucagon and insulin secretion in a paracrine manner. Recent studies have shown that δ-cells are couple with ß-cells to suppress α-cell activity. Under certain circumstances, δ-cells could also be trans-differentiated into insulin-producing ß-cells. Thus, pancreatic islet may benefit from δ-cell hyperplasia. However, an effective way to increase δ-cell mass has been rarely reported. Here, we found that REMD 2.59, a human monoclonal antibody and competitive antagonist of the glucagon receptor, massively boosted δ-cell number and increased plasma somatostatin level in both normoglycemic and type 1 diabetic (T1D) mice. The increased δ-cells were due to both δ-cell proliferation and derivation of duct lining cells. Notably, the enlarged δ-cell mass could reduce ß-cell burdens by inducing FoxO1 nuclear translocation in normoglycemic mice. Moreover, some somatostatin-positive cells were co-localized with C-peptide in T1D mice, suggesting that δ-cells might be a source of the newborn ß-cells. Collectively, these observations suggest that treatment with the glucagon receptor monoclonal antibody can increase pancreatic δ-cell mass by promoting self-replication and inducing duct-derived neogenesis both in normoglycemia and diabetic mice.


Subject(s)
Antibodies, Monoclonal/pharmacology , Hypoglycemic Agents/pharmacology , Receptors, Glucagon/antagonists & inhibitors , Somatostatin-Secreting Cells/metabolism , Animals , Animals, Newborn , Cell Proliferation/drug effects , Cell Shape , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/pathology , Glucagon/blood , Humans , Insulin/blood , Mice, Inbred C57BL , Somatostatin/blood , Somatostatin-Secreting Cells/drug effects
12.
EBioMedicine ; 41: 73-84, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30827929

ABSTRACT

BACKGROUND: Glucagon-like peptide-1 (GLP-1) and its based agents improve glycemic control. Although their attenuating effect on hepatic glucose output has drawn our attention for decades, the potential mechanisms remain unclear. METHODS: Cytokine array kit was used to assess cytokine profiles in db/db mice and mouse primary hepatocytes treated with exenatide (exendin-4). Two diabetic mouse models (db/db and Pax6m/+) were treated with a GLP-1 analog exenatide or liraglutide. The expression and secretion of fibroblast growth factor 21 (FGF21) in the livers of diabetic mice, primary mouse and human hepatocytes, and the human hepatic cell line HepG2 treated with or without GLP-1 analog were measured. Blockage of FGF21 with neutralizing antibody or siRNA, or hepatocytes isolated from Fgf21 knockout mice were used, and the expression and activity of key enzymes in gluconeogenesis were analyzed. Serum FGF21 level was evaluated in patients with type 2 diabetes (T2D) receiving exenatide treatment. FINDINGS: Utilizing the cytokine array, we identified that FGF21 secretion was upregulated by exenatide (exendin-4). Similarly, FGF21 production in hepatocytes was stimulated by exenatide or liraglutide. FGF21 blockage attenuated the inhibitory effects of the GLP-1 analogs on hepatic glucose output. Similar results were also observed in primary hepatocytes from Fgf21 knockout mice. Furthermore, exenatide treatment increased serum FGF21 level in patients with T2D, particularly in those with better glucose control. INTERPRETATION: We identify that function of GLP-1 in inhibiting hepatic glucose output is mediated via the liver hormone FGF21. Thus, we provide a new extra-pancreatic mechanism by which GLP-1 regulates glucose homeostasis. FUND: National Key Research and Development Program of China, the National Natural Science Foundation of China, the Natural Science Foundation of Beijing and Peking University Medicine Seed Fund for Interdisciplinary Research.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Fibroblast Growth Factors/metabolism , Glucagon-Like Peptide 1/metabolism , Glucose/metabolism , Liver/metabolism , Adult , Aged , Animals , Cells, Cultured , Diabetes Mellitus, Type 2/blood , Exenatide/pharmacology , Gluconeogenesis , Hep G2 Cells , Humans , Hypoglycemic Agents/pharmacology , Liraglutide/pharmacology , Liver/drug effects , Male , Mice , Mice, Inbred C57BL , Middle Aged
13.
Peptides ; 106: 83-90, 2018 08.
Article in English | MEDLINE | ID: mdl-30003931

ABSTRACT

The level of serum angiopoietin-like protein 8 (ANGPTL8), a novel hepatokine, is associated with obesity and type 2 diabetes mellitus (T2DM). The aims of this study were to investigate whether serum ANGPTL8 level in patients with T2DM was affected by treatment with exenatide, a glucagon-like peptide-1 receptor (GLP-1R) agonist, and to determine whether and how GLP-1R agonists regulated ANGPTL8 production in hepatocytes. A multiple-center trial was conducted in China. Among 240 patients with T2DM enrolled in this trial, 195 patients adhered to a 16-week exenatide treatment and follow-up. Human liver cell line HepG2 cells were incubated for 24 h with either exendin-4 (a native form of exenatide) or liraglutide in the presence or absence of GLP-1R antagonist exendin (9-39) and PI3K inhibitor LY294002. Change of serum ANGPTL8 level in patients with T2DM and regulation of ANGPTL8 production by the GLP-1R agonists in HepG2 cells were evaluated. Results showed that compared with baseline, exenatide treatment significantly increased serum ANGPTL8 level, and lowered body weight, fasting blood glucose (FBG) and glycated hemoglobin A1c (HbA1c) in patients with T2DM (all P <  0.05). The exenatide treatment-mediated upregulation of serum ANGPTL8 level was not associated with the levels of its lowering effects on body weight, FBG and HbA1c stratified by the median. Moreover, exendin-4 or liraglutide dose-dependently upregulated the level of ANGPTL8 expression and secretion in HepG2 cells, which was eliminated by adding exendin (9-39) and LY294002. In conclusion, GLP-1R agonists enhance ANGPTL8 production in vivo and in vitro, which is mediated via the PI3K/Akt pathway in a GLP-1R-dependent manner.


Subject(s)
Angiopoietin-like Proteins/blood , Diabetes Mellitus, Type 2/drug therapy , Exenatide/administration & dosage , Glucagon-Like Peptide-1 Receptor/agonists , Hypoglycemic Agents/administration & dosage , Peptide Hormones/blood , Adult , Aged , Angiopoietin-Like Protein 8 , China , Diabetes Mellitus, Type 2/blood , Exenatide/therapeutic use , Female , Hep G2 Cells , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Hypoglycemic Agents/therapeutic use , Male , Middle Aged , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism
14.
Med Sci Monit ; 24: 3848-3855, 2018 Jun 07.
Article in English | MEDLINE | ID: mdl-29877315

ABSTRACT

BACKGROUND The aim of this study was to characterize adenovirus-associated acute respiratory infection (ARI) and observe correlations between inflammatory markers and severity of human adenovirus type 7 (HAdV-7) infection, and to evaluate the potential of inflammatory markers to predict progression from upper-respiratory infection (URI) to adenovirus pneumonia (AdP). MATERIAL AND METHODS A total of 81 patients with adenovirus-associated ARI and confirmed HAdV-7 infection were enrolled. Cases were classified according to severity, as AdP and URI. Demographic and clinical data were collected retrospectively. Clinical features and serum inflammatory markers were evaluated and compared according to the severity of adenoviral infection. RESULTS We observed high-grade fever and strong inflammatory response in patients with HAdV-7-associated ARI. Procalcitonin (PCT), interleukin 6 (IL-6), and C-reactive protein concentrations were higher in patients with AdP than in those with URI. The mean erythrocyte sedimentation rate (ESR) was significantly higher in patients with AdP (p=0.008). Reduced serum prealbumin levels were observed in patients with HAdV-7 infection. In the analysis of URI to AdP prediction ability, areas under the curve (AUCs) for all inflammatory markers were <0.9. We found that 35.9% of pneumonia had ≥2 lobars of lung infiltrate and bilateral lung infiltrate, and 20% of patients with SP had pleural effusion and atelectasis. CONCLUSIONS IL-6 and ESR were associated with the severity of HAdV-7 respiratory infection. No inflammatory marker in our study predicted URI-to-AdP progression accurately. Lung infiltration and consolidation are common in HRCT in AdP. Multiple- or single-lobar/segment consolidation was most common in SP. SP progressed very quickly after onset.


Subject(s)
Adenovirus Infections, Human/metabolism , Respiratory Tract Infections/metabolism , Adenoviridae/metabolism , Adenovirus Infections, Human/blood , Adenoviruses, Human , Adolescent , Adult , Biomarkers/blood , Blood Sedimentation , C-Reactive Protein/analysis , Calcitonin/blood , Cohort Studies , Female , Humans , Interleukin-6/blood , Lung/metabolism , Male , Respiratory Tract Infections/blood , Respiratory Tract Infections/microbiology , Retrospective Studies , Severity of Illness Index , Young Adult
15.
Exp Ther Med ; 14(3): 2180-2188, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28962139

ABSTRACT

Asymptomatic pulmonary tuberculosis (PTB) mimicking lung cancer is rare and has been documented in few studies. Accurately diagnosing this atypical disease remains an enormous challenge for clinicians. The aim of the present study was to characterize asymptomatic patients with PTB who were initially diagnosed with lung cancer according to their chest computer tomography (CT) or whole-body 18F-fludeoxyglucose-positron emission tomography-computer tomography (PET-CT) presentations. The clinical characteristics and radiographic features of patients with PTB were analyzed and compared to those of patients with lung cancer. In patients with PTB, all lesions exhibited suspected malignant signs on chest CT and the maximum standard uptake value (SUVmax) of PET-CT imaging was between 2.65 and 10.9. Compared with lung cancer, the factors associated with PTB included an age <60 years (82% vs. 46%, P=0.03), being male (77% vs. 51%, P=0.025), the presence of diabetes (55% vs. 16%, P<0.01), spiculated margins (82% vs. 44%, P=0.002) and a lower SUVmax (P=0.036). The optimal cut-off level was SUVmax 8.45 for discriminating between PTB and lung cancer. At this point, the sensitivity and specificity were 63.0 and 88.9%, respectively. The results of the current study revealed methods of distinguishing between the two similar diseases. Furthermore, the results of the current study may increase awareness that although imaging of lesions may resemble lung cancer, a diagnosis of PTB should be considered. Accurate diagnosis of PTB would mean that patients would be able to avoid undergoing unnecessary operations that induce a high financial burden.

16.
PLoS One ; 12(5): e0176651, 2017.
Article in English | MEDLINE | ID: mdl-28531173

ABSTRACT

There is currently no convenient way to effectively evaluate whether a miliary tuberculosis patient is complicated with central nervous system (CNS) tuberculosis. We aimed to find such a way by analyzing the clinical data of these patients. Fifty patients with confirmed miliary tuberculosis and 31 patients with confirmed miliary tuberculosis complicated with CNS tuberculosis from 2010 to 2014 were selected. Their general conditions, clinical features and laboratory tests were analyzed. Factors that were significantly different between them were chosen to performed multivariate and univariate logistic regression analyses, and factors with significant P values were used to establish a scoring system. Eight factors, i.e., age, cough, nausea, headache, hemoglobin (HGB), serum albumin (ALB), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), were significantly different (P < 0.05). Multivariate logistic regression analysis showed that ALB was the independent risk predictor (HR = 1.29, 95% CI 1.09-1.52, P < 0.01), whereas the others were non-independent predictors except age (P < 0.05). The scoring system was based on a summation of the scores of the assigned values of the seven predictors and had an area under the curve (AUC) of 0.86 to confirm CNS tuberculosis, with a sensitivity of 81.5% and a specificity of 81.4% at a score of 0.75 and with a specificity of 95.3% at a score of 2.75. In contrast, a score below -0.75 excluded CNS tuberculosis, with a sensitivity of 88.9% and a specificity of 62.7%. The scoring system should be useful to evaluate whether a miliary tuberculosis patient is complicated with CNS tuberculosis and could help doctors avoid excessive investigation.


Subject(s)
Serum Albumin/metabolism , Tuberculosis, Central Nervous System/diagnosis , Tuberculosis, Miliary/complications , Tuberculosis, Miliary/metabolism , Adolescent , Adult , Age Factors , Area Under Curve , Blood Sedimentation , Child , Early Diagnosis , Female , Humans , Logistic Models , Male , Middle Aged , Retrospective Studies , Risk Factors , Sensitivity and Specificity , Tuberculosis, Central Nervous System/metabolism , Young Adult
17.
PLoS One ; 12(1): e0169100, 2017.
Article in English | MEDLINE | ID: mdl-28046003

ABSTRACT

The role of C-X-C motif chemokine 10 (CXCL10), a pro-inflammatory factor, in the development of acute respiratory distress syndrome (ARDS) remains unclear. In this study, we explored the role of CXCL10 and the effect of CXCL10 neutralization in lipopolysaccharide (LPS)-induced ARDS in rats. The expression of CXCL10 and its receptor chemokine receptor 3(CXCR3) increased after LPS induction. Moreover, neutralization of CXCL10 ameliorated the severity of ARDS by reducing pulmonary edema, inhibiting the release of inflammatory mediators (IFN-γ, IL-6 and ICAM-1) and limiting inflammatory cells (neutrophils, macrophages, CD8+ T cells) influx into the lung, with a reduction in CXCR3 expression in neutrophils and macrophages. Therefore, CXCL10 could be a potential therapeutic target in LPS-induced ARDS.


Subject(s)
Chemokine CXCL10/antagonists & inhibitors , Chemokine CXCL10/chemistry , Respiratory Distress Syndrome/drug therapy , Animals , Blood Gas Analysis , Bronchoalveolar Lavage Fluid , CD8-Positive T-Lymphocytes/metabolism , Chemokine CXCL11/metabolism , Chemokine CXCL9/metabolism , Disease Models, Animal , Inflammation , Intercellular Adhesion Molecule-1/metabolism , Interferon-gamma/metabolism , Interleukin-6/metabolism , Ligands , Lipopolysaccharides , Male , Rats , Rats, Wistar , Receptors, CXCR3/metabolism , Respiratory Distress Syndrome/chemically induced
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