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Xie C, Huang W, Sun Y, Xiang C, Trahair L, Jones KL, Horowitz M, Rayner CK, Wu T. Disparities in the Glycemic and Incretin Responses to Intraduodenal Glucose Infusion Between Healthy Young Men and Women. J Clin Endocrinol Metab 2023; 108:e712-e719. [PMID: 36987568 PMCID: PMC10438868 DOI: 10.1210/clinem/dgad176] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/23/2023] [Accepted: 03/23/2023] [Indexed: 03/30/2023] [Imported: 08/29/2023]
Abstract
CONTEXT Premenopausal women are at a lower risk of type 2 diabetes (T2D) compared to men, but the underlying mechanism(s) remain elusive. The secretion of the incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), from the small intestine is a major determinant of glucose homeostasis and may be influenced by sex. OBJECTIVES This study compared blood glucose and plasma insulin and incretin responses to intraduodenal glucose infusions in healthy young males and females. DESIGN In Study 1, 9 women and 20 men received an intraduodenal glucose infusion at 2 kcal/min for 60 minutes. In Study 2, 10 women and 26 men received an intraduodenal glucose at 3 kcal/min for 60 minutes. Venous blood was sampled every 15 minutes for measurements of blood glucose and plasma insulin, GLP-1 and GIP. RESULTS In response to intraduodenal glucose at 2 kcal/min, the incremental area under the curve between t = 0-60 minutes (iAUC0-60min) for blood glucose and plasma GIP did not differ between the 2 groups. However, iAUC0-60min for plasma GLP-1 (P = 0.016) and insulin (P = 0.011) were ∼2-fold higher in women than men. In response to intraduodenal glucose at 3 kcal/min, iAUC0-60min for blood glucose, plasma GIP, and insulin did not differ between women and men, but GLP-1 iAUC0-60min was 2.5-fold higher in women (P = 0.012). CONCLUSION Healthy young women exhibit comparable GIP but a markedly greater GLP-1 response to intraduodenal glucose than men. This disparity warrants further investigations to delineate the underlying mechanisms and may be of relevance to the reduced risk of diabetes in premenopausal women when compared to men.
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Affiliation(s)
- Cong Xie
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Weikun Huang
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
| | - Yixuan Sun
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
| | - Chunjie Xiang
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Laurence Trahair
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
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Xie C, Jalleh RJ, Watson LE, Huang W, Sun Y, Jones KL, Horowitz M, Rayner CK, Wu T. Determinants of blood glucose concentrations following a high carbohydrate meal in type 2 diabetes: A multiple linear regression analysis. Diabetes Res Clin Pract 2023; 198:110606. [PMID: 36893852 DOI: 10.1016/j.diabres.2023.110606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/31/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023] [Imported: 08/29/2023]
Abstract
This study showed that in relatively well-controlled type 2 diabetes blood glucose levels after a high carbohydrate meal were associated positively with fasting blood glucose, but also positively with gastric emptying in the first hour and negatively with the increments in plasma glucagon-like peptide-1 (GLP-1) in the later postprandial phase.
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Affiliation(s)
- Cong Xie
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Ryan J Jalleh
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Linda E Watson
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Weikun Huang
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Yixuan Sun
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia.
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Huang W, Xie C, Wewer Albrechtsen NJ, Jones KL, Horowitz M, Rayner CK, Wu T. The 'early' postprandial glucagon response is related to the rate of gastric emptying in type 2 diabetes. Peptides 2023; 161:170941. [PMID: 36623554 DOI: 10.1016/j.peptides.2023.170941] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/15/2022] [Accepted: 01/02/2023] [Indexed: 01/09/2023] [Imported: 08/29/2023]
Abstract
Gastric emptying (GE) is a major determinant of the postprandial glycemic and insulinemic responses in health and type 2 diabetes (T2D). However, the effect of GE on the postprandial glucagon response, which is characteristically augmented in T2D, is unknown. This study examined the relationship between plasma glucagon and GE of a standardized mixed meal in individuals with well-controlled T2D. 89 individuals with T2D (HbA1c 6.6 ± 0.1%) consumed a mashed potato meal labeled with 100 µL 13C-octanoic acid between 0 and 5 min. Venous blood was sampled frequently over 4 h for measurements of blood glucose and plasma glucagon. The gastric half-emptying time (T50) was calculated by quantification of 13C in the breath. Blood glucose peaked at t = 90 min after the meal. Plasma glucagon increased to a peak at t = 30 min and then decreased to a nadir at t = 180 min. The T50 was 68.3 ± 1.6 min. The incremental area under the plasma glucagon curve between t = 0-30 min (glucagon iAUC0-30 min) was related inversely to the T50 (r = -0.23, P = 0.029), while the increase in blood glucose at t = 30 min was related directly to the plasma glucagon iAUC0-30 min (r = 0.25, P = 0.018). Accordingly, individuals with relatively faster GE exhibited higher postprandial glucagon and glucose levels (ANOVA: P<0.01 for each). In well-controlled T2D, the early postprandial glucagon response to a mixed meal is related to the rate of GE, and predictive of the initial glycemic response. These observations suggest that a reduction in plasma glucagon may contribute to the effect of dietary and pharmacological strategies which reduce postprandial glycemia in T2D by slowing GE.
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Affiliation(s)
- Weikun Huang
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia
| | - Cong Xie
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia
| | | | - Karen L Jones
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia
| | - Michael Horowitz
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Christopher K Rayner
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Australia
| | - Tongzhi Wu
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia.
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Sang M, Xie C, Qiu S, Wang X, Horowitz M, Jones KL, Rayner CK, Sun Z, Wu T. Cholecystectomy is associated with dysglycaemia: Cross-sectional and prospective analyses. Diabetes Obes Metab 2022; 24:1656-1660. [PMID: 35491529 PMCID: PMC9545089 DOI: 10.1111/dom.14730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 04/09/2022] [Accepted: 04/26/2022] [Indexed: 12/30/2022] [Imported: 08/29/2023]
Abstract
Cholecystectomy has been reported to be associated with increased risk of diabetes in cross-sectional studies. In the current study, we performed both cross-sectional and prospective analyses to examine the association between cholecystectomy and dysglycaemia in Chinese community-dwelling adults. A total of 1612 participants (n = 1564 without cholecystectomy and n = 48 with cholecystectomy) were evaluated for glycaemic status (according to the World Health Organization (WHO) 1999 criteria) and then followed up over ~3.2 years. Percent changes (Δ) in fasting blood glucose and HbA1c from baseline at the follow-up visit were calculated to define glycaemic control as stable (-10% ≤ Δ < 10%), improved (Δ < -10%), or worsened (Δ ≥ 10%). The baseline cross-sectional analyses indicated that cholecystectomy was associated with an increased risk of both prediabetes and diabetes, while the prospective analysis indicated that cholecystectomy was also associated with a greater risk of deterioration in glycaemic control (ΔFPG ≥10% and ΔHbA1c ≥10%) (P < 0.05 for each, both before and after adjusting for potential confounding covariates). These observations suggest that individuals in the Chinese community-dwelling population who have undergone cholecystectomy are at increased risk of dysglycaemia. Further studies are warranted to both delineate the underlying mechanisms and to clarify whether more intense surveillance for future development of diabetes is needed in this group.
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Affiliation(s)
- Miaomiao Sang
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of MedicineSoutheast UniversityNanjingChina
| | - Cong Xie
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical SchoolThe University of AdelaideAdelaideSouth AustraliaAustralia
| | - Shanhu Qiu
- Department of General Practice, Zhongda Hospital, Institute of Diabetes, School of MedicineSoutheast UniversityNanjingChina
| | - Xuyi Wang
- Department of Clinical Nutrition, Zhongda Hospital, School of MedicineSoutheast UniversityNanjingChina
| | - Michael Horowitz
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical SchoolThe University of AdelaideAdelaideSouth AustraliaAustralia
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
| | - Karen L. Jones
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical SchoolThe University of AdelaideAdelaideSouth AustraliaAustralia
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
| | - Christopher K. Rayner
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical SchoolThe University of AdelaideAdelaideSouth AustraliaAustralia
- Department of Gastroenterology and HepatologyRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of MedicineSoutheast UniversityNanjingChina
| | - Tongzhi Wu
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical SchoolThe University of AdelaideAdelaideSouth AustraliaAustralia
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
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Wang X, Chen C, Xie C, Huang W, Young RL, Jones KL, Horowitz M, Rayner CK, Sun Z, Wu T. Serum bile acid response to oral glucose is attenuated in patients with early type 2 diabetes and correlates with 2-hour plasma glucose in individuals without diabetes. Diabetes Obes Metab 2022; 24:1132-1142. [PMID: 35238131 PMCID: PMC9540586 DOI: 10.1111/dom.14683] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/21/2022] [Accepted: 03/01/2022] [Indexed: 12/13/2022] [Imported: 08/29/2023]
Abstract
AIM To determine the serum bile acid (BA) response to 75-g oral glucose in individuals without diabetes, and whether this is attenuated in patients with 'early' type 2 diabetes (T2D) and related to the glycaemic response at 2 hours in either group. METHODS Forty newly diagnosed, treatment-naïve Han Chinese T2D subjects and 40 age-, gender-, and body mass index-matched controls without T2D ingested a 75-g glucose drink after an overnight fast. Plasma glucose and serum concentrations of total and individual BAs, fibroblast growth factor-19 (FGF-19), total glucagon-like peptide-1 (GLP-1), and insulin, were measured before and 2 hours after oral glucose. RESULTS Fasting total BA levels were higher in T2D than control subjects (P < .05). At 2 hours, the BA profile exhibited a shift from baseline in both groups, with increases in conjugated BAs and/or decreases in unconjugated BAs. There were increases in total BA and FGF-19 levels in control (both P < .05), but not T2D, subjects. Plasma glucose concentrations at 2 hours related inversely to serum total BA levels in control subjects (r = -0.42, P = .006). Total GLP-1 and the insulin/glucose ratio were increased at 2 hours in both groups, and the magnitude of the increase was greater in control subjects. CONCLUSIONS The serum BA response to a 75-g oral glucose load is attenuated in patients with 'early' T2D, as is the secretion of FGF-19 and GLP-1, while in individuals without T2D it correlates with 2-hour plasma glucose levels. These observations support a role for BAs in the regulation of postprandial glucose metabolism.
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Affiliation(s)
- Xuyi Wang
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
- Department of Clinical NutritionSoutheast UniversityNanjingChina
| | - Chang Chen
- Institute of Life SciencesChongqing Medical UniversityChongqingChina
| | - Cong Xie
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
| | - Weikun Huang
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
| | - Richard L. Young
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
- Nutrition, Diabetes & Gut Health, Lifelong Health ThemeSouth Australian Health & Medical Research InstituteAdelaideAustralia
| | - Karen L. Jones
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaide
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaide
| | - Christopher K. Rayner
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
- Department of Gastroenterology and HepatologyRoyal Adelaide HospitalAdelaideAustralia
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of MedicineSoutheast UniversityNanjing
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaide
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaide
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Sang MM, Sun ZL, Wu TZ. Inflammatory bowel disease and diabetes: Is there a link between them? World J Diabetes 2022; 13:126-128. [PMID: 35211249 PMCID: PMC8855140 DOI: 10.4239/wjd.v13.i2.126] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 12/09/2021] [Accepted: 01/14/2022] [Indexed: 02/06/2023] [Imported: 08/29/2023] Open
Abstract
Patients with inflammatory bowel disease (IBD) are reported to have an increased risk of diabetes. IBD therapies may also modulate blood glucose substantially. These observations are indicative of mechanistic connection(s) between IBD and diabetes.
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Affiliation(s)
- Miao-Miao Sang
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing 210009, Jiangsu Province, China
| | - Zi-Lin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing 210009, Jiangsu Province, China
| | - Tong-Zhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA 5000, Australia
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Borg MJ, Xie C, Rayner CK, Horowitz M, Jones KL, Wu T. Potential for Gut Peptide-Based Therapy in Postprandial Hypotension. Nutrients 2021; 13:nu13082826. [PMID: 34444986 PMCID: PMC8399874 DOI: 10.3390/nu13082826] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 08/06/2021] [Accepted: 08/14/2021] [Indexed: 02/07/2023] [Imported: 08/29/2023] Open
Abstract
Postprandial hypotension (PPH) is an important and under-recognised disorder resulting from inadequate compensatory cardiovascular responses to meal-induced splanchnic blood pooling. Current approaches to management are suboptimal. Recent studies have established that the cardiovascular response to a meal is modulated profoundly by gastrointestinal factors, including the type and caloric content of ingested meals, rate of gastric emptying, and small intestinal transit and absorption of nutrients. The small intestine represents the major site of nutrient-gut interactions and associated neurohormonal responses, including secretion of glucagon-like peptide-1, glucose-dependent insulinotropic peptide and somatostatin, which exert pleotropic actions relevant to the postprandial haemodynamic profile. This review summarises knowledge relating to the role of these gut peptides in the cardiovascular response to a meal and their potential application to the management of PPH.
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Affiliation(s)
- Malcolm J. Borg
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.X.); (C.K.R.); (M.H.); (K.L.J.)
| | - Cong Xie
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.X.); (C.K.R.); (M.H.); (K.L.J.)
| | - Christopher K. Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.X.); (C.K.R.); (M.H.); (K.L.J.)
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.X.); (C.K.R.); (M.H.); (K.L.J.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Karen L. Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.X.); (C.K.R.); (M.H.); (K.L.J.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.X.); (C.K.R.); (M.H.); (K.L.J.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
- Correspondence: ; Tel.: +61-8-8313-6535
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Xie C, Huang W, Young RL, Jones KL, Horowitz M, Rayner CK, Wu T. Role of Bile Acids in the Regulation of Food Intake, and Their Dysregulation in Metabolic Disease. Nutrients 2021; 13:nu13041104. [PMID: 33800566 PMCID: PMC8066182 DOI: 10.3390/nu13041104] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 02/07/2023] [Imported: 08/29/2023] Open
Abstract
Bile acids are cholesterol-derived metabolites with a well-established role in the digestion and absorption of dietary fat. More recently, the discovery of bile acids as natural ligands for the nuclear farnesoid X receptor (FXR) and membrane Takeda G-protein-coupled receptor 5 (TGR5), and the recognition of the effects of FXR and TGR5 signaling have led to a paradigm shift in knowledge regarding bile acid physiology and metabolic health. Bile acids are now recognized as signaling molecules that orchestrate blood glucose, lipid and energy metabolism. Changes in FXR and/or TGR5 signaling modulates the secretion of gastrointestinal hormones including glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), hepatic gluconeogenesis, glycogen synthesis, energy expenditure, and the composition of the gut microbiome. These effects may contribute to the metabolic benefits of bile acid sequestrants, metformin, and bariatric surgery. This review focuses on the role of bile acids in energy intake and body weight, particularly their effects on gastrointestinal hormone secretion, the changes in obesity and T2D, and their potential relevance to the management of metabolic disorders.
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Affiliation(s)
- Cong Xie
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
| | - Weikun Huang
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
- The ARC Center of Excellence for Nanoscale BioPhotonics, Institute for Photonics and Advanced Sensing, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia
| | - Richard L. Young
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
- Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute, Adelaide 5005, Australia
| | - Karen L. Jones
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5005, Australia
| | - Michael Horowitz
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5005, Australia
| | - Christopher K. Rayner
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide 5005, Australia
| | - Tongzhi Wu
- Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia; (C.X.); (W.H.); (R.L.Y.); (K.L.J.); (M.H.); (C.K.R.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5005, Australia
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing 210009, China
- Correspondence:
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Xie C, Huang W, Wang X, Trahair LG, Pham HT, Marathe CS, Young RL, Jones KL, Horowitz M, Rayner CK, Wu T. Gastric emptying in health and type 2 diabetes: An evaluation using a 75 g oral glucose drink. Diabetes Res Clin Pract 2021; 171:108610. [PMID: 33301790 DOI: 10.1016/j.diabres.2020.108610] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/14/2020] [Accepted: 12/03/2020] [Indexed: 02/07/2023] [Imported: 08/29/2023]
Abstract
AIM Gastric emptying is a major determinant of the glycaemic response to carbohydrate and is frequently abnormal in type 2 diabetes (T2DM). There is little information about how chronic glycaemic control affects gastric emptying in T2DM. We evaluated gastric emptying of a 75 g glucose drink in community-based patients with T2DM of short duration with good or poor glycaemic control, and compared this to young and older controls. METHODS T2DM patients managed by diet and/or metformin, either well-controlled or poorly-controlled, together with young and age-matched older controls without diabetes, consumed a 75 g oral glucose drink containing 150 mg 13C-acetate for evaluation of gastric emptying (breath test) and blood glucose over 180 min. RESULTS The gastric half-emptying time (T50) was longer in the older than the young non-diabetic subjects (P = 0.041), but shorter in well-controlled T2DM patients than age-matched older controls (P = 0.043). The T50 in poorly-controlled T2DM patients was shorter than in older controls (P = 0.006), but similar to young non-diabetic subjects. CONCLUSIONS Gastric emptying of a glucose drink is delayed with ageing, but more rapid in patients with T2DM of relatively short duration, regardless of their glycaemic status. These observations support interventions that slow gastric emptying to improve postprandial glycaemia in these patients with T2DM.
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Affiliation(s)
- Cong Xie
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Weikun Huang
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Xuyi Wang
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Laurence G Trahair
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Hung T Pham
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Chinmay S Marathe
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute, Adelaide, Australia
| | - Richard L Young
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute, Adelaide, Australia
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia.
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Sansome DJ, Jones KL, Horowitz M, Rayner CK, Wu T. Statins and glycaemic control in type 2 diabetes: Are bile acids relevant? Br J Clin Pharmacol 2020; 86:2538-2539. [PMID: 32232884 PMCID: PMC7688544 DOI: 10.1111/bcp.14274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/03/2020] [Accepted: 02/05/2020] [Indexed: 02/05/2023] [Imported: 08/29/2023] Open
Affiliation(s)
- Daniel J. Sansome
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaideAustralia
| | - Karen L. Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaideAustralia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaideAustralia
| | - Christopher K. Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaideAustralia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good HealthThe University of AdelaideAdelaideAustralia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of MedicineSoutheast UniversityNanjingChina
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11
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Wu T, Rayner CK, Jones KL, Xie C, Marathe C, Horowitz M. Role of intestinal glucose absorption in glucose tolerance. Curr Opin Pharmacol 2020; 55:116-124. [PMID: 33227625 DOI: 10.1016/j.coph.2020.10.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/11/2020] [Accepted: 10/19/2020] [Indexed: 02/06/2023] [Imported: 08/29/2023]
Abstract
Intestinal glucose absorption is integral to postprandial glucose homeostasis. Glucose absorption is dependent on a number of factors, including the exposure of carbohydrate to the mucosa of the upper gastrointestinal tract (determined particularly by the rates of gastric emptying and small intestinal transit), the digestion of complex carbohydrate into monosaccharides, and glucose sensing and transport by the intestinal mucosa. The absorption of glucose in the small intestine is not only a determinant of the appearance of exogenous glucose in the peripheral circulation, but is also coupled to the release of gastrointestinal hormones that in turn influence postprandial glucose metabolism through modulating gastrointestinal motor function, insulin and glucagon secretion, and subsequent energy intake. This review describes the physiology and pathophysiology of intestinal glucose absorption in health and type 2 diabetes, including its relevance to glucose tolerance and the management of postprandial hyperglycaemia.
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Affiliation(s)
- Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia; Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China.
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, Australia
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Cong Xie
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Chinmay Marathe
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
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Marathe CS, Jones KL, Wu T, Rayner CK, Horowitz M. Gastrointestinal autonomic neuropathy in diabetes. Auton Neurosci 2020; 229:102718. [PMID: 32916479 DOI: 10.1016/j.autneu.2020.102718] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/22/2020] [Accepted: 07/22/2020] [Indexed: 02/07/2023] [Imported: 08/29/2023]
Abstract
Gastrointestinal autonomic neuropathy represents an important and diverse, but poorly appreciated, manifestation of diabetic autonomic neuropathy that impacts negatively on quality of life. There is no test to assess gastrointestinal autonomic nerve damage directly in humans; cardiovascular autonomic reflex tests are often used as a surrogate, but are suboptimal. Gastrointestinal symptoms are common in diabetes, but usually correlate only weakly with disordered motility. Diabetic gastroparesis, or abnormally delayed gastric emptying, occurs frequently and is the best characterized manifestation of gastrointestinal autonomic neuropathy. There is a bi-directional relationship between postprandial glycaemia and the rate of gastric emptying. However, autonomic neuropathy can affect the function of any gut segment from the esophagus to the anus. Current management options for gastrointestinal autonomic neuropathy are, for the main part, empirical and sub-optimal.
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Affiliation(s)
- Chinmay S Marathe
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Australia.
| | - Karen L Jones
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Australia.
| | - Tongzhi Wu
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia.
| | - Christopher K Rayner
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Australia.
| | - Michael Horowitz
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Australia.
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Borg MJ, Rayner CK, Jones KL, Horowitz M, Xie C, Wu T. Gastrointestinal Mechanisms Underlying the Cardiovascular Effect of Metformin. Pharmaceuticals (Basel) 2020; 13:ph13110410. [PMID: 33266396 PMCID: PMC7700183 DOI: 10.3390/ph13110410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 02/07/2023] [Imported: 08/29/2023] Open
Abstract
Metformin, the most widely prescribed drug therapy for type 2 diabetes, has pleiotropic benefits, in addition to its capacity to lower elevated blood glucose levels, including mitigation of cardiovascular risk. The mechanisms underlying the latter remain unclear. Mechanistic studies have, hitherto, focused on the direct effects of metformin on the heart and vasculature. It is now appreciated that effects in the gastrointestinal tract are important to glucose-lowering by metformin. Gastrointestinal actions of metformin also have major implications for cardiovascular function. This review summarizes the gastrointestinal mechanisms underlying the action of metformin and their potential relevance to cardiovascular benefits.
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Affiliation(s)
- Malcolm J. Borg
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.K.R.); (K.L.J.); (M.H.); (C.X.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Christopher K. Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.K.R.); (K.L.J.); (M.H.); (C.X.)
| | - Karen L. Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.K.R.); (K.L.J.); (M.H.); (C.X.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.K.R.); (K.L.J.); (M.H.); (C.X.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Cong Xie
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.K.R.); (K.L.J.); (M.H.); (C.X.)
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5000, Australia; (M.J.B.); (C.K.R.); (K.L.J.); (M.H.); (C.X.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing 210096, China
- Correspondence: ; Tel.: +61-8-8313-6535
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Xie C, Jones KL, Rayner CK, Wu T. Enteroendocrine Hormone Secretion and Metabolic Control: Importance of the Region of the Gut Stimulation. Pharmaceutics 2020; 12:E790. [PMID: 32825608 DOI: 10.3390/pharmaceutics12090790] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 12/11/2022] [Imported: 08/29/2023] Open
Abstract
It is now widely appreciated that gastrointestinal function is central to the regulation of metabolic homeostasis. Following meal ingestion, the delivery of nutrients from the stomach into the small intestine (i.e., gastric emptying) is tightly controlled to optimise their subsequent digestion and absorption. The complex interaction of intraluminal nutrients (and other bioactive compounds, such as bile acids) with the small and large intestine induces the release of an array of gastrointestinal hormones from specialised enteroendocrine cells (EECs) distributed in various regions of the gut, which in turn to regulate gastric emptying, appetite and postprandial glucose metabolism. Stimulation of gastrointestinal hormone secretion, therefore, represents a promising strategy for the management of metabolic disorders, particularly obesity and type 2 diabetes mellitus (T2DM). That EECs are distributed distinctively between the proximal and distal gut suggests that the region of the gut exposed to intraluminal stimuli is of major relevance to the secretion profile of gastrointestinal hormones and associated metabolic responses. This review discusses the process of intestinal digestion and absorption and their impacts on the release of gastrointestinal hormones and the regulation of postprandial metabolism, with an emphasis on the differences between the proximal and distal gut, and implications for the management of obesity and T2DM.
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Zhang X, Jones KL, Horowitz M, Rayner CK, Wu T. Effects of Proximal and Distal Enteral Glucose Infusion on Cardiovascular Response in Health and Type 2 Diabetes. J Clin Endocrinol Metab 2020; 105:5851469. [PMID: 32497217 DOI: 10.1210/clinem/dgaa341] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/02/2020] [Accepted: 05/28/2020] [Indexed: 02/07/2023] [Imported: 08/29/2023]
Abstract
CONTEXT Exposure of the small intestine to nutrients frequently leads to marked reductions in blood pressure (BP) in type 2 diabetes (T2DM). It remains unclear whether the region of the gut exposed to nutrients influences postprandial cardiovascular responses. OBJECTIVE To evaluate the cardiovascular responses to proximal and distal small intestinal glucose infusion in health and T2DM. DESIGN Double-blind, randomized, crossover design. SETTING Single center in Australia. PATIENTS 10 healthy subjects and 10 T2DM patients. INTERVENTIONS Volunteers were studied on 2 occasions, when a transnasal catheter was positioned with infusion ports opening 13 cm and 190 cm beyond the pylorus. A 30-g bolus of glucose was infused into either site and 0.9% saline into the alternate site over 60 minutes. MAIN OUTCOME MEASURES BP, heart rate (HR), and superior mesenteric artery (SMA) blood flow were measured over 180 minutes. RESULTS Systolic BP was unchanged in response to both infusions in health, but decreased in T2DM, with a greater reduction after proximal versus distal infusion (all P ≤ .01). The increment in HR did not differ between treatments in health, but was greater after distal versus proximal infusion in T2DM (P = .02). The increases in SMA blood flow were initially greater, but less sustained, with proximal versus distal infusion in health (P < .001), a pattern less evident in T2DM. CONCLUSIONS In T2DM, postprandial hypotension may be mitigated by diversion of nutrients from the proximal to the distal small intestine.
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Affiliation(s)
- Xiang Zhang
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Department of General Surgery, Qilu Hospital of Shandong University, Jinan, China
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
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Huang WK, Xie C, Young RL, Zhao JB, Ebendorff-Heidepriem H, Jones KL, Rayner CK, Wu TZ. Development of innovative tools for investigation of nutrient-gut interaction. World J Gastroenterol 2020; 26:3562-3576. [PMID: 32742126 PMCID: PMC7366065 DOI: 10.3748/wjg.v26.i25.3562] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 05/29/2020] [Accepted: 06/17/2020] [Indexed: 02/06/2023] [Imported: 08/29/2023] Open
Abstract
The gastrointestinal tract is the key interface between the ingesta and the human body. There is wide recognition that the gastrointestinal response to nutrients or bioactive compounds, particularly the secretion of numerous hormones, is critical to the regulation of appetite, body weight and blood glucose. This concept has led to an increasing focus on “gut-based” strategies for the management of metabolic disorders, including type 2 diabetes and obesity. Understanding the underlying mechanisms and downstream effects of nutrient-gut interactions is fundamental to effective translation of this knowledge to clinical practice. To this end, an array of research tools and platforms have been developed to better understand the mechanisms of gut hormone secretion from enteroendocrine cells. This review discusses the evolution of in vitro and in vivo models and the integration of innovative techniques that will ultimately enable the development of novel therapies for metabolic diseases.
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Affiliation(s)
- Wei-Kun Huang
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, the University of Adelaide, Adelaide, SA 5005, Australia
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, SA 5005, Australia
- The ARC Centre of Excellence for Nanoscale BioPhotonics, Adelaide, SA 5005, Australia
| | - Cong Xie
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, the University of Adelaide, Adelaide, SA 5005, Australia
| | - Richard L Young
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, the University of Adelaide, Adelaide, SA 5005, Australia
- Diabetes, Nutrition and Gut Health, Lifelong Health, South Australia Health and Medical Research Institute, Adelaide, SA 5005, Australia
| | - Jiang-Bo Zhao
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, SA 5005, Australia
- The ARC Centre of Excellence for Nanoscale BioPhotonics, Adelaide, SA 5005, Australia
| | - Heike Ebendorff-Heidepriem
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, SA 5005, Australia
- The ARC Centre of Excellence for Nanoscale BioPhotonics, Adelaide, SA 5005, Australia
| | - Karen L Jones
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, the University of Adelaide, Adelaide, SA 5005, Australia
| | - Christopher K Rayner
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, the University of Adelaide, Adelaide, SA 5005, Australia
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, SA 5000, Australia
| | - Tong-Zhi Wu
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, the University of Adelaide, Adelaide, SA 5005, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing 210009, Jiangsu Province, China
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Jalleh R, Pham H, Marathe CS, Wu T, Buttfield MD, Hatzinikolas S, Malbert CH, Rigda RS, Lange K, Trahair LG, Feinle-Bisset C, Rayner CK, Horowitz M, Jones KL. Acute Effects of Lixisenatide on Energy Intake in Healthy Subjects and Patients with Type 2 Diabetes: Relationship to Gastric Emptying and Intragastric Distribution. Nutrients 2020; 12:nu12071962. [PMID: 32630191 PMCID: PMC7400134 DOI: 10.3390/nu12071962] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/24/2020] [Accepted: 06/29/2020] [Indexed: 02/07/2023] [Imported: 08/29/2023] Open
Abstract
Glucagon-like peptide-1 receptor agonists induce weight loss, which has been suggested to relate to the slowing of gastric emptying (GE). In health, energy intake (EI) is more strongly related to the content of the distal, than the total, stomach. We evaluated the effects of lixisenatide on GE, intragastric distribution, and subsequent EI in 15 healthy participants and 15 patients with type 2 diabetes (T2D). Participants ingested a 75-g glucose drink on two separate occasions, 30 min after lixisenatide (10 mcg) or placebo subcutaneously, in a randomised, double-blind, crossover design. GE and intragastric distribution were measured for 180 min followed by a buffet-style meal, where EI was quantified. Relationships of EI with total, proximal, and distal stomach content were assessed. In both groups, lixisenatide slowed GE markedly, with increased retention in both the proximal (p < 0.001) and distal (p < 0.001) stomach and decreased EI (p < 0.001). EI was not related to the content of the total or proximal stomach but inversely related to the distal stomach at 180 min in health on placebo (r = -0.58, p = 0.03) but not in T2D nor after lixisenatide in either group. In healthy and T2D participants, the reduction in EI by lixisenatide is unrelated to changes in GE/intragastric distribution, consistent with a centrally mediated effect.
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Affiliation(s)
- Ryan Jalleh
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide SA 5000, Australia; (R.J.); (C.S.M.); (T.W.); (M.H.)
| | - Hung Pham
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Chinmay S. Marathe
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide SA 5000, Australia; (R.J.); (C.S.M.); (T.W.); (M.H.)
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Tongzhi Wu
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide SA 5000, Australia; (R.J.); (C.S.M.); (T.W.); (M.H.)
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Madeline D. Buttfield
- School of Health Sciences, University of South Australia, Adelaide SA 5001, Australia;
| | - Seva Hatzinikolas
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Charles H. Malbert
- Aniscan, Institut National de la Rechercher Agronomique, 35590 Saint-Gilles, France;
| | - Rachael S. Rigda
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Kylie Lange
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Laurence G. Trahair
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Christine Feinle-Bisset
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Christopher K. Rayner
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide SA 5000, Australia
| | - Michael Horowitz
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide SA 5000, Australia; (R.J.); (C.S.M.); (T.W.); (M.H.)
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
| | - Karen L. Jones
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide SA 5000, Australia; (R.J.); (C.S.M.); (T.W.); (M.H.)
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide SA 5000, Australia; (H.P.); (S.H.); (R.S.R.); (K.L.); (L.G.T.); (C.F.-B.); (C.K.R.)
- Correspondence: ; Tel.: +61-8-83137821
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Xie C, Wang X, Jones KL, Horowitz M, Sun Z, Little TJ, Rayner CK, Wu T. Role of endogenous glucagon-like peptide-1 enhanced by vildagliptin in the glycaemic and energy expenditure responses to intraduodenal fat infusion in type 2 diabetes. Diabetes Obes Metab 2020; 22:383-392. [PMID: 31693275 DOI: 10.1111/dom.13906] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/18/2019] [Accepted: 10/31/2019] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
AIM To evaluate the effects of the dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin on glycaemic and energy expenditure responses during intraduodenal fat infusion, as well as the contribution of endogenous glucagon-like peptide-1 (GLP-1) signalling, in people with type 2 diabetes (T2DM). METHODS A total of 15 people with T2DM managed by diet and/or metformin (glycated haemoglobin 49.3 ± 2.1 mmol/mol) were studied on three occasions (two with vildagliptin and one with placebo) in a double-blind, randomized, crossover fashion. On each day, vildagliptin 50 mg or placebo was given orally, followed by intravenous exendin (9-39) 600 pmol/kg/min, on one of the two vildagliptin treatment days, or 0.9% saline over 180 minutes. At between 0 and 120 minutes, a fat emulsion was infused intraduodenally at 2 kcal/min. Energy expenditure, plasma glucose and glucose-regulatory hormones were evaluated. RESULTS Intraduodenal fat increased plasma GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), insulin and glucagon, and energy expenditure, and decreased plasma glucose (all P < 0.05). On the two intravenous saline days, plasma glucose and glucagon were lower, plasma intact GLP-1 was higher (all P < 0.05), and energy expenditure tended to be lower after vildagliptin (P = 0.08) than placebo. On the two vildagliptin days, plasma glucose, glucagon and GLP-1 (both total and intact), and energy expenditure were higher during intravenous exendin (9-39) than saline (all P < 0.05). CONCLUSIONS In well-controlled T2DM during intraduodenal fat infusion, vildagliptin lowered plasma glucose and glucagon, and tended to decrease energy expenditure, effects that were mediated by endogenous GLP-1.
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Affiliation(s)
- Cong Xie
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Xuyi Wang
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Tanya J Little
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
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Sansome DJ, Xie C, Veedfald S, Horowitz M, Rayner CK, Wu T. Mechanism of glucose-lowering by metformin in type 2 diabetes: Role of bile acids. Diabetes Obes Metab 2020; 22:141-148. [PMID: 31468642 DOI: 10.1111/dom.13869] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/07/2019] [Accepted: 08/28/2019] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is an increasingly prevalent chronic condition, characterized by abnormally elevated blood glucose concentrations and, as a consequence, increased risk of micro- and macrovascular complications. Metformin is usually the first-line glucose-lowering medication in T2DM; however, despite being used for more than 60 years, the mechanism underlying the glucose-lowering action of metformin remains incompletely understood. Although metformin reduces hepatic glucose production, there is persuasive evidence that the gastrointestinal tract is crucial in mediating this effect, particularly via secretion of the incretin hormone glucagon-like peptide 1 (GLP-1). It is now well recognized that bile acids, in addition to their established function in fat digestion and absorption, are important regulators of glucose metabolism. Exposure of the small and large intestine to bile acids induces GLP-1 secretion, modulates the composition of the gut microbiota, and reduces postprandial blood glucose excursions in humans with and without T2DM. Metformin reduces intestinal bile acid resorption substantially, such that intraluminal bile acids may, at least in part, account for its glucose-lowering effect. The present review focuses on the conceptual shift in our understanding as to how metformin lowers blood glucose in T2DM, with a particular emphasis on the role of intestinal bile acids.
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Affiliation(s)
- Daniel J Sansome
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Cong Xie
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Simon Veedfald
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
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Xie C, Wang X, Jones KL, Horowitz M, Sun Z, Little TJ, Rayner CK, Wu T. Comparative Effects of Intraduodenal Glucose and Fat Infusion on Blood Pressure and Heart Rate in Type 2 Diabetes. Front Nutr 2020; 7:582314. [PMID: 33240919 PMCID: PMC7680846 DOI: 10.3389/fnut.2020.582314] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 10/19/2020] [Indexed: 02/05/2023] [Imported: 08/29/2023] Open
Abstract
The interaction of nutrients with the small intestine modulates postprandial cardiovascular function. Rapid small intestinal nutrient delivery may reduce blood pressure markedly, particularly in patients with type 2 diabetes (T2DM). Postprandial hypotension occurs in ~30% of patients with longstanding T2DM, but there is little information about the cardiovascular effects of different macronutrients. We compared the blood pressure and heart rate responses to standardized intraduodenal glucose and fat infusions in T2DM. Two parallel groups, including 26 T2DM patients who received intraduodenal glucose infusion and 14 T2DM patients who received intraduodenal fat, both at 2 kcal/min over 120 min, were compared retrospectively. Blood pressure and heart rate were measured at regular intervals. Systolic blood pressure was stable initially and increased slightly thereafter in both groups, without any difference between them. Diastolic blood pressure decreased in response to intraduodenal glucose, but remained unchanged in response to lipid, with a significant difference between the two infusions (P = 0.04). Heart rate increased during both intraduodenal glucose and lipid infusions (P < 0.001 each), and the increment was greater in response to intraduodenal fat than glucose (P = 0.004). In patients with T2DM, intraduodenal fat induced a greater increase in heart rate, associated with a diminished reduction in blood pressure, when compared with isocaloric glucose. The macronutrient composition of meals may be an important consideration in T2DM patients with symptomatic postprandial hypotension.
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Affiliation(s)
- Cong Xie
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
| | - Xuyi Wang
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Karen L. Jones
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Tanya J. Little
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
| | - Christopher K. Rayner
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, SA, Australia
- *Correspondence: Tongzhi Wu
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Pham H, Holen IS, Phillips LK, Hatzinikolas S, Huynh LQ, Wu T, Hausken T, Rayner CK, Horowitz M, Jones KL. The Effects of a Whey Protein and Guar Gum-Containing Preload on Gastric Emptying, Glycaemia, Small Intestinal Absorption and Blood Pressure in Healthy Older Subjects. Nutrients 2019; 11:nu11112666. [PMID: 31694157 PMCID: PMC6893806 DOI: 10.3390/nu11112666] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 10/25/2019] [Accepted: 10/28/2019] [Indexed: 02/07/2023] [Imported: 08/29/2023] Open
Abstract
A whey protein/guar gum preload reduces postprandial glycaemia in type 2 diabetes through slowing gastric emptying. However, gastric emptying has previously been assessed using a stable isotope breath test technique, which cannot discriminate between slowing of gastric emptying and small intestinal absorption. This preload also may be useful in the management of postprandial hypotension. We evaluated the effects of a whey protein/guar preload on gastric emptying, glucose absorption, glycaemic/insulinaemic and blood pressure (BP) responses to an oral glucose load. Eighteen healthy older participants underwent measurements of gastric emptying (scintigraphy), plasma glucose and insulin, glucose absorption, superior mesenteric artery (SMA) flow, BP and heart rate (HR) after ingesting a 50 g glucose drink, with or without the preload. The preload reduced plasma glucose (p = 0.02) and serum 3-O-methylglucose (3-OMG) (p = 0.003), and increased plasma insulin (p = 0.03). There was no difference in gastric emptying or BP between the two days. The reduction in plasma glucose on the preload day was related to the reduction in glucose absorption (r = 0.71, p = 0.002). In conclusion, the glucose-lowering effect of the preload may relate to delayed small intestinal glucose absorption and insulin stimulation, rather than slowing of gastric emptying.
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Affiliation(s)
- Hung Pham
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
| | - Iselin S. Holen
- Department of Clinical Medicine, University of Bergen, 5021 Bergen, Norway; (I.S.H.); (T.H.)
| | - Liza K. Phillips
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Seva Hatzinikolas
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
| | - Lian Q. Huynh
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
| | - Tongzhi Wu
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Trygve Hausken
- Department of Clinical Medicine, University of Bergen, 5021 Bergen, Norway; (I.S.H.); (T.H.)
| | - Christopher K. Rayner
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Michael Horowitz
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
| | - Karen L. Jones
- Centre of Research Excellence in Translating Nutritional Science to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia; (H.P.); (L.K.P.); (S.H.); (L.Q.H.); (T.W.); (C.K.R.); (M.H.)
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide 5000, Australia
- Correspondence: ; Tel.: +61-8-8313-7821
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Borg MJ, Jones KL, Sun Z, Horowitz M, Rayner CK, Wu T. Metformin attenuates the postprandial fall in blood pressure in type 2 diabetes. Diabetes Obes Metab 2019; 21:1251-1254. [PMID: 30615231 DOI: 10.1111/dom.13632] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 01/04/2019] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
Metformin has been shown to modulate the cardiovascular response to intraduodenal glucose in patients with type 2 diabetes (T2DM), and may have the capacity to regulate postprandial blood pressure (BP), which is often inadequately compensated in T2DM, resulting in postprandial hypotension. In the present study, we evaluated the acute effects of metformin on the BP and heart rate (HR) responses to oral glucose in patients with T2DM. Ten diet-controlled T2DM patients were evaluated on two occasions in a double-blind, randomized, crossover design. Participants received either metformin 1 g or saline (control) intraduodenally 60 minutes before ingesting a 50 g glucose drink labelled with 150 mg 13 C-acetate. BP, HR, plasma glucagon-like peptide-1 (GLP-1) and gastric emptying (breath test) were evaluated over 180 minutes. Systolic and diastolic BP decreased and HR increased after oral glucose (P < 0.001 for all) on both days. Metformin attenuated the fall in systolic BP (P < 0.001), increased plasma GLP-1 concentrations (P < 0.05) and slowed gastric emptying (P < 0.05) without significantly affecting diastolic BP or HR. In conclusion, metformin acutely attenuates the hypotensive response to oral glucose, associated with augmented GLP-1 secretion and delayed gastric emptying, effects potentially relevant to its favourable cardiovascular profile.
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Affiliation(s)
- Malcolm J Borg
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
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Zhang X, Young RL, Bound M, Hu S, Jones KL, Horowitz M, Rayner CK, Wu T. Comparative Effects of Proximal and Distal Small Intestinal Glucose Exposure on Glycemia, Incretin Hormone Secretion, and the Incretin Effect in Health and Type 2 Diabetes. Diabetes Care 2019; 42:520-528. [PMID: 30765429 DOI: 10.2337/dc18-2156] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/16/2019] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
OBJECTIVE Cells releasing glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) are distributed predominately in the proximal and distal gut, respectively. Hence, the region of gut exposed to nutrients may influence GIP and GLP-1 secretion and impact on the incretin effect and gastrointestinal-mediated glucose disposal (GIGD). We evaluated glycemic and incretin responses to glucose administered into the proximal or distal small intestine and quantified the corresponding incretin effect and GIGD in health and type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODS Ten healthy subjects and 10 patients with T2DM were each studied on four occasions. On two days, a transnasal catheter was positioned with infusion ports opening 13 cm and 190 cm beyond the pylorus, and 30 g glucose with 3 g 3-O-methylglucose (a marker of glucose absorption) was infused into either site and 0.9% saline into the alternate site over 60 min. Matching intravenous isoglycemic clamp studies were performed on the other two days. Blood glucose, serum 3-O-methylglucose, and plasma hormones were evaluated over 180 min. RESULTS In both groups, blood glucose and serum 3-O-methylglucose concentrations were higher after proximal than distal glucose infusion (all P < 0.001). Plasma GLP-1 increased minimally after proximal, but substantially after distal, glucose infusion, whereas GIP increased promptly after both infusions, with concentrations initially greater, but less sustained, with proximal versus distal infusion (all P < 0.001). Both the incretin effect and GIGD were less with proximal than distal glucose infusion (both P ≤ 0.009). CONCLUSIONS The distal, as opposed to proximal, small intestine is superior in modulating postprandial glucose metabolism in both health and T2DM.
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Affiliation(s)
- Xiang Zhang
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Department of General Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Richard L Young
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Nutrition and Metabolism, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Michelle Bound
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
| | - Sanyuan Hu
- Department of General Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Karen L Jones
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Michael Horowitz
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
| | - Tongzhi Wu
- Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, South Australia, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing, Jiangsu, China
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Borg MJ, Bound M, Grivell J, Sun Z, Jones KL, Horowitz M, Rayner CK, Wu T. Comparative effects of proximal and distal small intestinal administration of metformin on plasma glucose and glucagon-like peptide-1, and gastric emptying after oral glucose, in type 2 diabetes. Diabetes Obes Metab 2019; 21:640-647. [PMID: 30370686 DOI: 10.1111/dom.13567] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 10/17/2018] [Accepted: 10/25/2018] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
AIMS The gastrointestinal tract, particularly the lower gut, may be key to the anti-diabetic action of metformin. We evaluated whether administration of metformin into the distal, vs the proximal, small intestine would be more effective in lowering plasma glucose by stimulating glucagon-like pepetide-1 (GLP-1) and/or slowing gastric emptying (GE) in type 2 diabetes (T2DM). MATERIALS AND METHODS Ten diet-controlled T2DM patients were studied on three occasions. A transnasal catheter was positioned with proximal and distal infusion ports located 13 and 190 cm beyond the pylorus, respectively. Participants received infusions of (a) proximal + distal saline (control), (b) proximal metformin (1000 mg) + distal saline or (c) proximal saline + distal metformin (1000 mg) over 5 minutes, followed 60 minutes later by a glucose drink containing 50 g glucose and 150 mg 13 C-acetate. "Arterialized" venous blood and breath samples were collected over 3 hours for measurements of plasma glucose, GLP-1, insulin and glucagon, and GE, respectively. RESULTS Compared with control, both proximal and distal metformin reduced plasma glucose and augmented GLP-1 responses to oral glucose comparably (P < 0.05 each), without affecting plasma insulin or glucagon. GE was slower after proximal metformin than after control (P < 0.05) and tended to be slower after distal metformin, without any difference between proximal and distal metformin. CONCLUSIONS In diet-controlled T2DM patients, glucose-lowering via a single dose of metformin administered to the upper and lower gut was comparable and was associated with stimulation of GLP-1 and slowing of GE. These observations suggest that the site of gastrointestinal administration is not critical to the glucose-lowering capacity of metformin.
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Affiliation(s)
- Malcolm J Borg
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michelle Bound
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Jacqueline Grivell
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Karen L Jones
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Michael Horowitz
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
| | - Christopher K Rayner
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Tongzhi Wu
- Adelaide Medical School, Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
- Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, Australia
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Xie C, Wang X, Young RL, Horowitz M, Rayner CK, Wu T. Role of Intestinal Bitter Sensing in Enteroendocrine Hormone Secretion and Metabolic Control. Front Endocrinol (Lausanne) 2018; 9:576. [PMID: 30319553 PMCID: PMC6171477 DOI: 10.3389/fendo.2018.00576] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/10/2018] [Indexed: 02/05/2023] [Imported: 08/29/2023] Open
Abstract
The gastrointestinal tract stores ingested nutrients in the stomach which are then delivered to the small intestine at a controlled rate to optimize their digestion and absorption. The interaction of nutrients with the small and large intestine generates feedback that slows gastric emptying, induces satiation, and reduces postprandial glycemic excursions. The mechanisms underlying these nutrient-gut interactions are complex; it has only recently been appreciated that the gut has the capacity to detect intraluminal contents in much the same way as the tongue, via activation of specific G-protein-coupled receptors, and that ensuing signaling mechanisms modulate the release of an array of gut hormones that influence gastrointestinal motility, appetite and glycemia. Interestingly, evidence from preclinical models supports a functional link between intestinal bitter taste receptor (BTRs) and gastrointestinal hormone secretion, and the outcomes of recent studies indicate that stimulation of intestinal BTRs may be used to modulate gastrointestinal function, to diminish energy intake and limit postprandial blood glucose excursions in humans. This review summarizes current evidence about the expression and function of intestinal BTRs in relation to enteroendocrine hormone release and discusses the clinical implications of this pathway for the management of obesity and type 2 diabetes.
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Affiliation(s)
- Cong Xie
- Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
| | - Xuyi Wang
- Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
| | - Richard L. Young
- Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Nutrition and Metabolism, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Michael Horowitz
- Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
| | - Christopher K. Rayner
- Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
| | - Tongzhi Wu
- Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, SA, Australia
- Institute of Diabetes, School of Medicine, Southeast University, Nanjing, China
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Wu T, Marathe CS, Horowitz M, Jones KL, Rayner CK. Comment on Russell-Jones et al. Diabetes Care 2017;40:943-950. Comment on Bowering et al. Diabetes Care 2017;40:951-957. Diabetes Care 2018; 41:e27-e28. [PMID: 29463669 DOI: 10.2337/dc17-1916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine and National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Chinmay S Marathe
- Discipline of Medicine and National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michael Horowitz
- Discipline of Medicine and National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Discipline of Medicine and National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Christopher K Rayner
- Discipline of Medicine and National Health and Medical Research Council Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
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Wu T, Rayner CK, Watson LE, Jones KL, Horowitz M, Little TJ. Comparative effects of intraduodenal fat and glucose on the gut-incretin axis in healthy males. Peptides 2017; 95:124-127. [PMID: 28800948 DOI: 10.1016/j.peptides.2017.08.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/24/2017] [Accepted: 08/02/2017] [Indexed: 02/07/2023] [Imported: 08/29/2023]
Abstract
BACKGROUND The interaction of nutrients with the small intestine stimulates the secretion of numerous enteroendocrine hormones that regulate postprandial metabolism. However, differences in gastrointestinal hormonal responses between the macronutrients are incompletely understood. In the present study, we compared blood glucose and plasma hormone concentrations in response to standardised intraduodenal (ID) fat and glucose infusions in healthy humans. METHODS In a parallel study design, 16 healthy males who received an intraduodenal fat infusion were compared with 12 healthy males who received intraduodenal glucose, both at a rate of 2kcal/min over 120min. Venous blood was sampled at frequent intervals for measurements of blood glucose, and plasma total and active glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), insulin and glucagon. RESULTS Plasma concentrations of the incretin hormones (both total and active GLP-1 and GIP) and glucagon were higher, and plasma insulin and blood glucose concentrations lower, during intraduodenal fat, when compared with intraduodenal glucose, infusion (treatment by time interaction: P<0.001 for each). CONCLUSIONS Compared with glucose, intraduodenal fat elicits substantially greater GLP-1, GIP and glucagon secretion, with minimal effects on blood glucose or plasma insulin in healthy humans. These observations are consistent with the concept that fat is a more potent stimulus of the 'gut-incretin' axis than carbohydrate.
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Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia.
| | - Christopher K Rayner
- Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Linda E Watson
- Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michael Horowitz
- Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Tanya J Little
- Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
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Wu T, Trahair LG, Little TJ, Bound MJ, Zhang X, Wu H, Sun Z, Horowitz M, Rayner CK, Jones KL. Effects of Vildagliptin and Metformin on Blood Pressure and Heart Rate Responses to Small Intestinal Glucose in Type 2 Diabetes. Diabetes Care 2017; 40:702-705. [PMID: 28258090 DOI: 10.2337/dc16-2391] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 02/16/2017] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
OBJECTIVE To evaluate effects of vildagliptin and metformin on blood pressure (BP) and heart rate (HR) responses to intraduodenal (ID) glucose in diet-controlled type 2 diabetes. RESEARCH DESIGN AND METHODS Study A compared vildagliptin (50 mg) and placebo, given 60 min before a 120-min ID glucose infusion at 2 or 4 kcal/min (ID2 or ID4) in 16 patients. Study B compared metformin (850 mg) and placebo, given 30 min before ID2 over 120 min in 9 patients. RESULTS Systolic (P = 0.002) and diastolic (P < 0.001) BP were lower and HR greater (P = 0.005) after vildagliptin compared with placebo, without interaction between vildagliptin and the glucose infusion rate. In contrast, HR was greater after metformin than placebo (P < 0.001), without any difference in systolic or diastolic BP. CONCLUSIONS Vildagliptin reduces BP and increases HR, whereas metformin increases HR without affecting BP during ID glucose infusion in type 2 diabetes. These distinct cardiovascular profiles during enteral nutrient exposure may have implications for postprandial hypotension.
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Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Laurence G Trahair
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Tanya J Little
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michelle J Bound
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Xiang Zhang
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Department of General Surgery, Qilu Hospital of Shandong University, Jinan, China
| | - Hang Wu
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
- Department of Endocrinology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Zilin Sun
- Department of Endocrinology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Michael Horowitz
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Christopher K Rayner
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
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Abstract
Metformin is established as the first-line therapy for type 2 diabetes (T2DM), but its mode of action remains elusive. Elucidation of the mechanisms underlying the anti-diabetic action of metformin may have the potential to optimise its glucose-lowering efficacy and lead to the development of agents acting on novel targets for the management of type 2 diabetes. Areas covered: This review highlights key pharmacokinetic features of metformin, summarises recent insights into its hepatic and gastrointestinal actions relevant to blood glucose homeostasis, and discusses the common gastrointestinal side effects of metformin. Literature concerning these areas was reviewed on PubMed. Expert commentary: The mechanisms by which metformin improves glycaemic control in type 2 diabetes are complex. Although novel hepatic pathways continue to be reported in preclinical studies, there is a lack of human evidence for most of these. Considering the fundamental role of the gastrointestinal tract in the regulation of blood glucose homeostasis and pleiotropic actions of metformin on several gastrointestinal targets relevant to glycaemic control, the gut is likely to represent at least as important a site of metformin action as the liver in the management of type 2 diabetes.
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Affiliation(s)
- Tongzhi Wu
- a Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health , The University of Adelaide , Adelaide , Australia
| | - Michael Horowitz
- a Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health , The University of Adelaide , Adelaide , Australia
| | - Christopher K Rayner
- a Discipline of Medicine and Centre of Research Excellence in Translating Nutritional Science to Good Health , The University of Adelaide , Adelaide , Australia
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Wu T, Xie C, Wu H, Jones KL, Horowitz M, Rayner CK. Metformin reduces the rate of small intestinal glucose absorption in type 2 diabetes. Diabetes Obes Metab 2017; 19:290-293. [PMID: 27761984 DOI: 10.1111/dom.12812] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 10/13/2016] [Accepted: 10/14/2016] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
In rodents, metformin slows intestinal glucose absorption, potentially increasing exposure of the distal gut to glucose to enhance postprandial glucagon-like peptide-1 (GLP-1) secretion. We evaluated the effects of metformin on serum 3-O-methylglucose (3-OMG; a marker of glucose absorption) and plasma total GLP-1 concentrations during a standardized intraduodenal infusion of glucose and 3-OMG in patients with type 2 diabetes. A total of 12 patients, treated with metformin 850 mg twice daily or placebo for 7 days each in a double-blind, randomized, crossover design (14 days' washout between treatments), were evaluated on days 5 or 8 of each treatment (6 subjects each). On each study day, 30 minutes after ingesting 850 mg metformin or placebo, patients received an infusion of glucose (60 g + 5 g 3-OMG, dissolved in water to 240 mL) via an intraduodenal catheter over the course of 120 minutes. Compared with placebo, metformin was associated with lower serum 3-OMG ( P < .001) and higher plasma total GLP-1 ( P = .003) concentrations. The increment in plasma GLP-1 after metformin vs placebo was related to the reduction in serum 3-OMG concentrations ( P = .019). Accordingly, metformin inhibits small intestinal glucose absorption, which may contribute to augmented GLP-1 secretion in type 2 diabetes.
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Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Cong Xie
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Medical School, Southeast University, Nanjing, China
| | - Hang Wu
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
- Medical School, Southeast University, Nanjing, China
| | - Karen L Jones
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Michael Horowitz
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, South Australia, Australia
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Wu T, Zhang X, Trahair LG, Bound MJ, Little TJ, Deacon CF, Horowitz M, Jones KL, Rayner CK. Small Intestinal Glucose Delivery Affects the Lowering of Blood Glucose by Acute Vildagliptin in Type 2 Diabetes. J Clin Endocrinol Metab 2016; 101:4769-4778. [PMID: 27598511 DOI: 10.1210/jc.2016-2813] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] [Imported: 08/29/2023]
Abstract
CONTEXT The rate of gastric emptying is an important determinant of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) secretion and may influence the magnitude of glucose lowering by dipeptidyl peptidase-4 (DPP-4) inhibitors. OBJECTIVE To evaluate the effects of the DPP-4 inhibitor, vildagliptin (VILD), during intraduodenal (ID) glucose infusion at 2 different rates within the physiological range of gastric emptying, in type 2 diabetes. PARTICIPANTS AND DESIGN A total of 16 diet-controlled type 2 diabetic patients were studied on 4 separate days in double-blind, randomized, fashion. On each day, either 5-mg VILD or placebo (PLBO) was given 60 minutes before a 120-minute ID glucose infusion at 2 or 4 kcal/min (ID2 or ID4). Plasma glucose and hormones were measured frequently. RESULTS Plasma glucose, insulin, C-peptide, glucagon, total GIP, and total and intact GLP-1 concentrations were higher during ID4 than ID2 (P < .01 for each). Compared with PLBO, VILD was associated with higher intact GLP-1, insulin, and C-peptide and lower glucose and total GIP and GLP-1 (P < .01 for each), without affecting glucagon. There were significant interactions between the rate of ID glucose and VILD treatment on plasma glucose, intact and total GLP-1, and GIP (P < .05 for each) but not insulin, C-peptide, or glucagon. The reduction in glucose and the increment in intact GLP-1 after VILD vs PLBO were 3.3- and 3.8-fold greater, respectively, during ID4 compared with ID2. CONCLUSIONS/INTERPRETATION These observations warrant further study to clarify whether type 2 diabetic patients with relatively more rapid gastric emptying have greater glucose lowering during treatment with DPP-4 inhibitors.
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Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Xiang Zhang
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Laurence G Trahair
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Michelle J Bound
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Tanya J Little
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Carolyn F Deacon
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Michael Horowitz
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Karen L Jones
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
| | - Christopher K Rayner
- Discipline of Medicine (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health (T.W., X.Z., L.G.T., M.J.B., T.J.L., M.H., K.L.J., C.K.R.), The University of Adelaide, Adelaide, Australia; and Department of Biomedical Science (C.F.D.), University of Copenhagen, Copenhagen, Denmark
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Wu T, Little TJ, Bound MJ, Borg M, Zhang X, Deacon CF, Horowitz M, Jones KL, Rayner CK. A Protein Preload Enhances the Glucose-Lowering Efficacy of Vildagliptin in Type 2 Diabetes. Diabetes Care 2016; 39:511-7. [PMID: 26786576 DOI: 10.2337/dc15-2298] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/24/2015] [Indexed: 02/05/2023] [Imported: 08/29/2023]
Abstract
OBJECTIVE Nutrient "preloads" given before meals can attenuate postprandial glycemic excursions, at least partly by slowing gastric emptying and stimulating secretion of the incretins (i.e., glucagon-like peptide-1 [GLP-1] and glucose-dependent insulinotropic polypeptide [GIP]). This study was designed to evaluate whether a protein preload could improve the efficacy of the dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin to increase incretin concentrations, slow gastric emptying, and lower postprandial glycemia in type 2 diabetes. RESEARCH DESIGN AND METHODS Twenty-two patients with type 2 diabetes treated with metformin were studied on four occasions, receiving either 50 mg vildagliptin (VILD) or placebo (PLBO) on both the evening before and the morning of each study day. The latter dose was followed after 60 min by a preload drink containing either 25 g whey protein (WHEY) or control flavoring (CTRL), and after another 30 min by a (13)C-octanoate-labeled mashed potato meal. Plasma glucose and hormones, and gastric emptying, were evaluated. RESULTS Compared with PLBO/CTRL, PLBO/WHEY reduced postprandial peak glycemia, increased plasma insulin, glucagon, and incretin hormones (total and intact), and slowed gastric emptying, whereas VILD/CTRL reduced both the peak and area under the curve for glucose, increased plasma intact incretins, and slowed gastric emptying but suppressed plasma glucagon and total incretins (P < 0.05 each). Compared with both PLBO/WHEY and VILD/CTRL, VILD/WHEY was associated with higher plasma intact GLP-1 and GIP, slower gastric emptying, and lower postprandial glycemia (P < 0.05 each). CONCLUSIONS In metformin-treated type 2 diabetes, a protein preload has the capacity to enhance the efficacy of vildagliptin to slow gastric emptying, increase plasma intact incretins, and reduce postprandial glycemia.
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Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Tanya J Little
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michelle J Bound
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Malcolm Borg
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
| | - Xiang Zhang
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Carolyn F Deacon
- Department of Biomedical Science, University of Copenhagen, Copenhagen, Denmark
| | - Michael Horowitz
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Christopher K Rayner
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
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