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Amssayef A, Eddouks M. Alkaloids as Promising Agents for the Management of Insulin Resistance: A Review. Curr Pharm Des 2023; 29:3123-3136. [PMID: 38038009 DOI: 10.2174/0113816128270340231121043038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/10/2023] [Accepted: 09/21/2023] [Indexed: 12/02/2023]
Abstract
BACKGROUND Insulin resistance is one of the main factors that lead to the development of type 2 diabetes mellitus (T2DM). The effect of alkaloids on insulin resistance has been extensively examined according to multiple scientific researches. OBJECTIVE In this work, we aimed to summarize the interesting results from preclinical and clinical studies that assessed the effects of natural alkaloids (berberine, nigelladine A, piperine, trigonelline, capsaicin, nuciferine, evodiamine, mahanine, and magnoflorine) on impaired insulin sensitivity and worsened insulin resistance, which play a pivotal role in the pathogenesis of type 2 diabetes. METHODS In the current review, PubMed, ScienceDirect, Springer, and Google Scholar databases were used. The inclusion criteria were based on the following keywords and phrases: insulin sensitivity, insulin resistance, alkaloids and insulin resistance, alkaloids and type 2 diabetes, mechanisms of action, and alkaloids. RESULTS The outcomes reported in this review demonstrated that the selected alkaloids increased insulin sensitivity and reduced insulin resistance in vitro and in vivo evidence, as well as in clinical trials, through improving insulin-signaling transduction mainly in hepatocytes, myocytes, and adipocytes, both at cellular and molecular levels. Insulin signaling components (InsR, IRS-1, PI3K, Akt, etc.), protein kinases and phosphatases, receptors, ion channels, cytokines, adipokines, and microRNAs, are influenced by alkaloids at transcriptional and translational levels, also in terms of function (activity and/or phosphorylation). Multiple perturbations associated with insulin resistance, such as ectopic lipid accumulation, inflammation, ER stress, oxidative stress, mitochondrial dysfunction, gut microbiota dysbiosis, and β-cell failure, are reversed after treatment with alkaloids. Furthermore, various indices and tests are employed to assess insulin resistance, including the Matsuda index, insulin sensitivity index (ISI), oral glucose tolerance test (OGTT), and insulin tolerance test (ITT), which are all enhanced by alkaloids. These improvements extend to fasting blood glucose, fasting insulin, and HbA1c levels as well. Additionally, the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and the Homeostasis Model Assessment of β-cell function (HOMA-β) are recognized as robust markers of insulin sensitivity and β-cell function, and it is noteworthy that alkaloids also lead to improvements in these two markers. CONCLUSION Based on the findings of the current review, alkaloids may serve as both preventive and curative agents for metabolic disorders, specifically type 2 diabetes. Nonetheless, there is an urgent need for additional clinical trials to explore the potential benefits of alkaloids in both healthy individuals and those with type 2 diabetes. Additionally, it is crucial to assess any possible side effects and interactions with antidiabetic drugs.
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Affiliation(s)
- Ayoub Amssayef
- Department of Biology, Faculty of Sciences and Techniques Errachidia, Moulay Ismail University of Meknes, BP 509, Boutalamine, Errachidia, Morocco
| | - Mohamed Eddouks
- Department of Biology, Faculty of Sciences and Techniques Errachidia, Moulay Ismail University of Meknes, BP 509, Boutalamine, Errachidia, Morocco
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Michałowska J, Miller-Kasprzak E, Seraszek-Jaros A, Mostowska A, Bogdański P. The Link between Three Single Nucleotide Variants of the GIPR Gene and Metabolic Health. Genes (Basel) 2022; 13:genes13091534. [PMID: 36140702 PMCID: PMC9498707 DOI: 10.3390/genes13091534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/26/2022] Open
Abstract
Single nucleotide variants (SNVs) of the GIPR gene have been associated with BMI and type 2 diabetes (T2D), suggesting the role of the variation in this gene in metabolic health. To increase our understanding of this relationship, we investigated the association of three GIPR SNVs, rs11672660, rs2334255 and rs10423928, with anthropometric measurements, selected metabolic parameters, and the risk of excessive body mass and metabolic syndrome (MS) in the Polish population. Normal-weight subjects (n = 340, control group) and subjects with excessive body mass (n = 600, study group) participated in this study. For all participants, anthropometric measurements and metabolic parameters were collected, and genotyping was performed using the high-resolution melting curve analysis. We did not find a significant association between rs11672660, rs2334255 and rs10423928 variants with the risk of being overweight. Differences in metabolic and anthropometric parameters were found for investigated subgroups. An association between rs11672660 and rs10423928 with MS was identified. Heterozygous CT genotype of rs11672660 and AT genotype of rs10423928 were significantly more frequent in the group with MS (OR = 1.38, 95%CI: 1.03–1.85; p = 0.0304 and OR = 1.4, 95%CI: 1.05–1.87; p = 0.0222, respectively). Moreover, TT genotype of rs10423928 was less frequent in the MS group (OR = 0.72, 95%CI: 0.54–0.95; p = 0.0221).
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Affiliation(s)
- Joanna Michałowska
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, 61-701 Poznan, Poland
- Correspondence:
| | - Ewa Miller-Kasprzak
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, 61-701 Poznan, Poland
| | - Agnieszka Seraszek-Jaros
- Department of Bioinformatics and Computational Biology, Poznan University of Medical Sciences, 61-701 Poznan, Poland
| | - Adrianna Mostowska
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, 61-701 Poznan, Poland
| | - Paweł Bogdański
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, 61-701 Poznan, Poland
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Ismail M, Stagling S, Lundberg A, Nystrom FH. A cross-over study of postprandial effects from moist snuff and red wine on metabolic rate, appetite-related hormones and glucose. Drug Alcohol Depend 2022; 236:109479. [PMID: 35580478 DOI: 10.1016/j.drugalcdep.2022.109479] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/18/2022]
Abstract
PURPOSE To compare acute effects of moist snuff with or without nicotine and red wine with or without alcohol on prandial hormones and metabolism. BASIC PROCEDURES AND METHODS Two deciliters of wine, with or without alcohol, were taken together with a standardized supervised meal in 14 healthy women and men. All participants also combined the meal with usage of with moist snuff, with or without nicotine. The snuff was replaced hourly at each of the four settings, i.e. snuff with or without nicotine combined with red wine with or without alcohol, that started at 0800 o'clock and were finished at noon. MAIN FINDINGS We found ghrelin levels to be more efficiently suppressed when drinking red wine with alcohol compared to non-alcoholic wine by analyzing area under the curve (AUC). AUC for regular wine was 370 ± 98 pg/ml x hours and 559 ± 154 pg/ml x hours for de-alcoholized red wine, p < 0.0001 by general linear model. The postprandial metabolic rate was further elevated following alcohol containing red wine compared with non-alcoholic red wine (p = 0.022). Although glucose levels were not uniformly lower after alcoholic red wine, we found lowered glucose levels 3 h after the meal (mean glucose wine: 4.38 ± 0.96 mmol/l, non-alcoholic wine: 4.81 ± 0.77 mmol/l, p = 0.005). Nicotine-containing moist snuff (AUC: 1406 ± 149 nmol/ml x hours) elevated the levels of serum cortisol compared with nicotine-free snuff (AUC: 1268 ± 119 nmol/ml x hours, p = 0.005). We found no effects of nicotine or alcohol on feelings of satiety. CONCLUSIONS Alcohol in red wine augmented the postprandial suppression of ghrelin and it also lowered postprandial glucose 3 h post-meal. These effects are in line with observational trials linking regular intake of moderate amounts of red wine with lower risk for diabetes.
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Affiliation(s)
- Midean Ismail
- Department of Health Medicine and Caring Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Samuel Stagling
- Department of Health Medicine and Caring Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Anna Lundberg
- Department of Health Medicine and Caring Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Fredrik H Nystrom
- Department of Health Medicine and Caring Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.
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Seaweed-Derived Proteins and Peptides: Promising Marine Bioactives. Antioxidants (Basel) 2022; 11:antiox11010176. [PMID: 35052680 PMCID: PMC8773382 DOI: 10.3390/antiox11010176] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 12/29/2022] Open
Abstract
Seaweeds are a typical food of East-Asian cuisine, to which are alleged several beneficial health effects have been attributed. Their availability and their nutritional and chemical composition have favored the increase in its consumption worldwide, as well as a focus of research due to their bioactive properties. In this regard, seaweed proteins are nutritionally valuable and comprise several specific enzymes, glycoproteins, cell wall-attached proteins, red algae phycobiliproteins, lectins, peptides, or mycosporine-like amino acids. This great extent of molecules has been reported to exert significant antioxidant, antimicrobial, anti-inflammatory, antihypertensive, antidiabetic, or antitumoral properties. Hence, knowledge on algae proteins and derived compounds have gained special interest for the potential nutraceutical, cosmetic or pharmaceutical industries based on these bioactivities. Although several molecular mechanisms of action on how these proteins and peptides exert biological activities have been described, many gaps in knowledge still need to be filled. Updating the current knowledge related to seaweed proteins and peptides is of interest to further asses their potential health benefits. This review addresses the characteristics of seaweed protein and protein-derived molecules, their natural occurrence, their studied bioactive properties, and their described potential mechanisms of action.
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Michałowska J, Miller-Kasprzak E, Seraszek-Jaros A, Mostowska A, Bogdański P. Association of GLP1R variants rs2268641 and rs6923761 with obesity and other metabolic parameters in a Polish cohort. Front Endocrinol (Lausanne) 2022; 13:1000185. [PMID: 36339410 PMCID: PMC9626533 DOI: 10.3389/fendo.2022.1000185] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/29/2022] [Indexed: 12/03/2022] Open
Abstract
INTRODUCTION Obesity is a complex disease associated with excessive fat accumulation and numerous metabolic complications. So far, many factors leading to the development of this disorder have been identified, including genetic susceptibility. Various studies linked GLP1R variants with anthropometric and metabolic parameters, suggesting the role of the variation in this gene in metabolic health. OBJECTIVE The aim of this study is to investigate the association of two single nucleotide variants of GLP1R gene, rs2268641 and rs6923761, with excessive weight, metabolic syndrome, anthropometric measurements and selected metabolic parameters. METHODS Normal-weight subjects (n= 340, control group) and subjects with excessive body mass (n = 600, study group) participated in this study. For all participants, anthropometric measurements and metabolic parameters were collected, and genotyping of the two single nucleotide variants of GLP1R gene, rs2268641 and rs6923761, was performed using the high-resolution melting curve analysis. RESULTS Significant differences in the genotype distribution of rs2268641 were found, where homozygous TT genotype was significantly less frequent in the study group with excessive body mass (OR=0.66; p=0.0298). For rs6923761, A allele and homozygous AA genotype were significantly more frequent in the study group with excessive weight than in the control group (OR=1.27; p=0.0239 and OR=1.69; p=0.0205, respectively). The association of studied variants with metabolic parameters was found for rs6923761. For this variant, AA carriers had higher body mass in comparison to GG carriers (p=0.0246), and AA carriers had higher glucose concentration in comparison to AG carriers (p=0.0498). We did not find an association of rs2268641 and rs6923761 with metabolic syndrome. CONCLUSION In our study, AA carriers of rs6923761 had higher risk of excessive body mass, whereas TT carriers of rs2268641 had lower risk of being overweight. Moreover, homozygous carriers of the minor allele of rs6923761 had higher glucose concentration in comparison to heterozygous subjects. None of the studied variants were associated with metabolic syndrome in the studied population.
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Affiliation(s)
- Joanna Michałowska
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, Poznan, Poland
- *Correspondence: Joanna Michałowska,
| | - Ewa Miller-Kasprzak
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, Poznan, Poland
| | - Agnieszka Seraszek-Jaros
- Department of Bioinformatics and Computational Biology, Poznan University of Medical Sciences, Poznan, Poland
| | - Adrianna Mostowska
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, Poznan, Poland
| | - Paweł Bogdański
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, Poznan, Poland
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Cuevas Fernández FJ, García Marrero MR, Iglesias Girón MJ, Pérez de Armas AA, Cerdeña Rodríguez E, Cabrera León A, Aguirre-Jaime A. [Effectiveness of the TG/HDL-C ratio to improve GLP-1 prescription in patients with type 2 diabetes in primary care]. Semergen 2021; 47:521-530. [PMID: 34154909 DOI: 10.1016/j.semerg.2021.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/28/2021] [Accepted: 05/16/2021] [Indexed: 11/20/2022]
Abstract
AIMS Check the usefulness of ratio TG/HDL-C≥2.5 to improve the effectiveness of GLP-1 prescribing in patients with type 2 diabetes (DM2) in primary care, and determine whether any patient profile would higher benefit. DESIGN Descriptive cross-sectional study. LOCATION Barranco Grande Health Center, Tenerife. PARTICIPANTS Random selection of patients with DM2 attended by 12 family doctors and 12 nurses. MAIN MEASUREMENTS Poor control according to the current criteria was compared to poor control according to the proposed rule. To determine who would benefit, the sociodemographic, clinical, therapeutic and follow-up characteristics were analyzed. Descriptive, bivariate and multivariate statistical analysis was performed. RESULTS No predominant characteristics were found in the patients who would be prescribed GLP-1 according to the proposed rule, but those that reached a significance P<.20 were included as potential explanatory factors in a multivariate binary logistic regression model. The adjustment of the model retained the factors of therapeutic non-compliance (OR 3.40 [1.58-5.02]; P=.003), evolution of DM2 less than 15 years (OR 2.74 [1.10-4.89]; P=.031), number of prescribed anti-diabetes drugs (OR 2.30 [1.88-2.81]; P<.001) and age under 65 years (OR 1.67 [1.08-2.58]; P=.021). CONCLUSIONS The use of the rule that we propose for the prescription of GLP-1 (2018 recommendations of the GDPS network combined with the TG/HDL-C ratio≥2.5 or BMI≥30kg/m2), instead of the current criterion adopted by the National Health System, would allow to broaden the spectrum of application of the drug in patients with poor control of their DM2.
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Affiliation(s)
- F J Cuevas Fernández
- Gerencia de Atención Primaria, Santa Cruz de Tenerife, España; Área de Medina Preventiva y Salud Pública, Universidad de La Laguna. San Cristóbal de La Laguna, Santa Cruz de Tenerife, España.
| | | | | | | | | | - A Cabrera León
- Área de Medina Preventiva y Salud Pública, Universidad de La Laguna. San Cristóbal de La Laguna, Santa Cruz de Tenerife, España; Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, España
| | - A Aguirre-Jaime
- Servicio de Investigación en Cuidados, Colegio de Enfermeros, Santa Cruz de Tenerife, España
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Marrano N, Biondi G, Borrelli A, Cignarelli A, Perrini S, Laviola L, Giorgino F, Natalicchio A. Irisin and Incretin Hormones: Similarities, Differences, and Implications in Type 2 Diabetes and Obesity. Biomolecules 2021; 11:286. [PMID: 33671882 PMCID: PMC7918991 DOI: 10.3390/biom11020286] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 02/09/2021] [Accepted: 02/12/2021] [Indexed: 12/11/2022] Open
Abstract
Incretins are gut hormones that potentiate glucose-stimulated insulin secretion (GSIS) after meals. Glucagon-like peptide-1 (GLP-1) is the most investigated incretin hormone, synthesized mainly by L cells in the lower gut tract. GLP-1 promotes β-cell function and survival and exerts beneficial effects in different organs and tissues. Irisin, a myokine released in response to a high-fat diet and exercise, enhances GSIS. Similar to GLP-1, irisin augments insulin biosynthesis and promotes accrual of β-cell functional mass. In addition, irisin and GLP-1 share comparable pleiotropic effects and activate similar intracellular pathways. The insulinotropic and extra-pancreatic effects of GLP-1 are reduced in type 2 diabetes (T2D) patients but preserved at pharmacological doses. GLP-1 receptor agonists (GLP-1RAs) are therefore among the most widely used antidiabetes drugs, also considered for their cardiovascular benefits and ability to promote weight loss. Irisin levels are lower in T2D patients, and in diabetic and/or obese animal models irisin administration improves glycemic control and promotes weight loss. Interestingly, recent evidence suggests that both GLP-1 and irisin are also synthesized within the pancreatic islets, in α- and β-cells, respectively. This review aims to describe the similarities between GLP-1 and irisin and to propose a new potential axis-involving the gut, muscle, and endocrine pancreas that controls energy homeostasis.
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Affiliation(s)
| | | | | | | | | | | | - Francesco Giorgino
- Department of Emergency and Organ Transplantation, Section of Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, I-70124 Bari, Italy; (N.M.); (G.B.); (A.B.); (A.C.); (S.P.); (L.L.); (A.N.)
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Proença C, Ribeiro D, Freitas M, Carvalho F, Fernandes E. A comprehensive review on the antidiabetic activity of flavonoids targeting PTP1B and DPP-4: a structure-activity relationship analysis. Crit Rev Food Sci Nutr 2021; 62:4095-4151. [PMID: 33554619 DOI: 10.1080/10408398.2021.1872483] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Type 2 diabetes (T2D) is an expanding global health problem, resulting from defects in insulin secretion and/or insulin resistance. In the past few years, both protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl peptidase-4 (DPP-4), as well as their role in T2D, have attracted the attention of the scientific community. PTP1B plays an important role in insulin resistance and is currently one of the most promising targets for the treatment of T2D, since no available PTP1B inhibitors were still approved. DPP-4 inhibitors are among the most recent agents used in the treatment of T2D (although its use has been associated with possible cardiovascular adverse events). The antidiabetic properties of flavonoids are well-recognized, and include inhibitory effects on the above enzymes, although hitherto not therapeutically explored. In the present study, a comprehensive review of the literature of both synthetic and natural isolated flavonoids as inhibitors of PTP1B and DPP-4 activities is made, including their type of inhibition and experimental conditions, and structure-activity relationship, covering a total of 351 compounds. We intend to provide the most favorable chemical features of flavonoids for the inhibition of PTP1B and DPP-4, gathering information for the future development of compounds with improved potential as T2D therapeutic agents.
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Affiliation(s)
- Carina Proença
- LAQV, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Daniela Ribeiro
- LAQV, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Marisa Freitas
- LAQV, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Félix Carvalho
- UCIBIO, REQUIMTE, Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Eduarda Fernandes
- LAQV, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
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Incretin Hormones in Obesity and Related Cardiometabolic Disorders: The Clinical Perspective. Nutrients 2021; 13:nu13020351. [PMID: 33503878 PMCID: PMC7910956 DOI: 10.3390/nu13020351] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 02/06/2023] Open
Abstract
The prevalence of obesity continues to grow rapidly worldwide, posing many public health challenges of the 21st century. Obese subjects are at major risk for serious diet-related noncommunicable diseases, including type 2 diabetes mellitus, cardiovascular disease, and non-alcoholic fatty liver disease. Understanding the mechanisms underlying obesity pathogenesis is needed for the development of effective treatment strategies. Dysregulation of incretin secretion and actions has been observed in obesity and related metabolic disorders; therefore, incretin-based therapies have been developed to provide new therapeutic options. Incretin mimetics present glucose-lowering properties, together with a reduction of appetite and food intake, resulting in weight loss. In this review, we describe the physiology of two known incretins—glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), and their role in obesity and related cardiometabolic disorders. We also focus on the available and incoming incretin-based medications that can be used in the treatment of the above-mentioned conditions.
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Shen X, Luo L, Yang M, Lin Y, Li J, Yang L. Exendin‑4 inhibits lipotoxicity‑induced oxidative stress in β‑cells by inhibiting the activation of TLR4/NF‑κB signaling pathway. Int J Mol Med 2020; 45:1237-1249. [PMID: 32124969 DOI: 10.3892/ijmm.2020.4490] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 12/02/2019] [Indexed: 11/05/2022] Open
Abstract
The present study aimed to investigate the relationship between the protective effects of exendin‑4 (EX‑4) on lipotoxicity‑induced oxidative stress and meta‑inflammation in β‑cells and the toll‑like receptor 4 (TLR4)/NF‑κB signaling pathway. Lipotoxicity, hydrogen peroxide (H2O2)‑induced oxidative stress in β cells, obese Sprague Dawley rats and TLR4 truncation rats were utilized in the present study. The expression levels were detected by western blotting; cell apoptosis was detected by TUNEL assay; and the intracellular reactive oxygen species (ROS) levels were analyzed using a ROS assay kit. The findings of the present study showed that EX‑4 inhibited the expression of TLR4, NF‑κB p65 subunit and p47phox in a concentration‑dependent manner, and decreased the intracellular level of ROS. Additionally, silencing of TLR4 expression enhanced the protective effects of EX‑4, while overexpression of TLR4 attenuated these protective influences. Simultaneously, it was demonstrated that TLR4 was involved in the process of EX‑4 intervention to inhibit H2O2‑induced oxidative stress in islet β‑cells. Moreover, it was found that EX‑4 also inhibited TLR4‑ or NF‑κB agonist‑induced oxidative stress. These results were also confirmed in an animal model of obese rats, in which EX‑4 was able to improve the function of β‑cells, attenuate oxidative stress, and inhibit the expression levels of TLR4 and NF‑κB p65 subunit in the pancreas of the diet‑induced obese rats. Furthermore, truncation of the TLR4 gene in SD rats delayed the aforementioned damage. In summary, EX‑4 may inhibit lipotoxicity‑induced oxidative stress in β‑cells by inhibiting the activation of the TLR4/NF‑κB signaling pathway.
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Affiliation(s)
- Ximei Shen
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Liufen Luo
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Meng Yang
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Yuxi Lin
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Jing Li
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Liyong Yang
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
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Antonopoulou V, Karras SN, Koufakis T, Yavropoulou M, Katsiki N, Gerou S, Papavramidis T, Kotsa K. Rising Glucagon-Like Peptide 1 Concentrations After Parathyroidectomy in Patients With Primary Hyperparathyroidism. J Surg Res 2020; 245:22-30. [DOI: 10.1016/j.jss.2019.07.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 05/26/2019] [Accepted: 07/11/2019] [Indexed: 01/16/2023]
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Albinsson-Stenholm E, Bergsén J, Ingves S, Vilhelmsson N, Guldbrand H, Nystrom FH. Subjects with high fasting insulin also have higher postprandial GLP-1 and glucagon levels than controls with lower insulin. Nutr Res 2019; 72:111-120. [PMID: 31759769 DOI: 10.1016/j.nutres.2019.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/18/2019] [Accepted: 10/22/2019] [Indexed: 11/28/2022]
Abstract
Little is known about postprandial release of serum ghrelin, glucagon, and glucagon-like peptide-1 (GLP-1) in relation with differing fasting insulin levels. We hypothesized that these hormones are affected by insulin resistance, and hence, we compared different postprandial responses of GLP-1, glucagon, and ghrelin in subjects with relatively high (RHI) or relatively low (RLI) fasting insulin levels. The trial was a randomized crossover study with 4 different meal conditions. Fourteen nonobese or obese, healthy, men and 14 women were randomly assigned to the order of supervised intake of a 750 kcal drink with the same protein contents but with 20 energy-percent (E%) or 55 E% from carbohydrates, and the remaining energy from fat. Participants were also randomized to consume the drinks as 1 large beverage or as five 150-kcal portions every 30 minutes. The 28 subjects were divided into 2 equally sized groups based on fasting insulin levels. Statistics were done with general linear mixed model. Fasting insulin levels were 3-fold higher in the group with RHI compared with the RLI group (RHI: 1004 ± 510 pg/mL, RLI: 324 ± 123 pg/mL, P < .0005). Serum GLP-1 was highest in the RHI group after both single meals and after 5 drinks and following high- and low-carbohydrate meals (both P ≤ .002), and this was the case also for glucagon levels (both P ≤ .018), whereas ghrelin levels did not differ between groups. Thus, subjects with RHI displayed both higher postprandial serum GLP-1 and glucagon than the participants with RLI, suggesting that glucagon could play a role in the advent of dysglycemia by insulin resistance.
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Affiliation(s)
- Erina Albinsson-Stenholm
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Johannes Bergsén
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Simon Ingves
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Nathalie Vilhelmsson
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Hans Guldbrand
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Fredrik H Nystrom
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.
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Daley EJ, Pajevic PD, Roy S, Trackman PC. Impaired Gastric Hormone Regulation of Osteoblasts and Lysyl Oxidase Drives Bone Disease in Diabetes Mellitus. JBMR Plus 2019; 3:e10212. [PMID: 31687648 PMCID: PMC6820454 DOI: 10.1002/jbm4.10212] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/06/2019] [Accepted: 06/11/2019] [Indexed: 12/15/2022] Open
Abstract
Diabetic bone disease is a complication of type I and type II diabetes, both of which are increasing in the United States and elsewhere. Increased hip and foot fracture rates do not correlate well with changes in bone mineral density (BMD), whereas studies support the importance of collagen structure to bone strength. Extracellular lysyl oxidase (LOX) catalyzes the oxidative deamination of hydroxylysine and lysine residues in collagens resulting in aldehydes that subsequently form critically important biosynthetic crosslinks that stabilize functional collagens. Although LOX-dependent biosynthetic crosslinks in bone collagen are deficient in diabetic bone, the expression and regulation of bone LOXs in diabetes have not been comprehensively studied. Here, we found that LOX is profoundly downregulated in bone in diabetes. Moreover, we have identified a novel metabolic regulatory relationship that is dysregulated in diabetes using mouse models. Data indicate that the incretin (gastric hormone) known as glucose-dependent insulinotropic polypeptide (GIP) that is anabolic to osteoblasts strongly upregulates LOX, and that this regulation is disrupted in the streptozotocin-induced model of diabetes in mice. In vivo and in vitro studies support that diabetes results in elevated circulating peripheral dopamine, likely also derived from the gut, and is responsible for blocking GIP signaling and LOX levels in osteoblasts. Moreover, peripheral administration of the dopamine D2 receptor antagonist amisulpride to diabetic mice restored trabecular bone structure to near normal and partially reversed downregulation of LOX. Taken together our data identifies a novel metabolic relationship between the gut-derived hormone GIP and bone-derived LOX, and points to the importance of LOX dysregulation in the pathology of diabetic bone disease. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
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Affiliation(s)
- Eileen J Daley
- Boston University Henry M. Goldman School of Dental Medicine, Department of Molecular and Cell BiologyBostonMAUSA
| | - Paola Divieti Pajevic
- Boston University Henry M. Goldman School of Dental Medicine, Department of Molecular and Cell BiologyBostonMAUSA
| | - Sayon Roy
- Boston University School of Medicine, Department of MedicineBostonMAUSA
| | - Philip C Trackman
- Boston University Henry M. Goldman School of Dental Medicine, Department of Molecular and Cell BiologyBostonMAUSA
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14
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Han M, Xu Y, Yuan J, Zhu Y, Zhou J, Liu L, Li X, Zhang H. Circulating neuromedin U levels are similar in subjects with NGT and newly diagnosed T2DM and do not correlate with insulin secretion. Diabetes Res Clin Pract 2019; 151:163-168. [PMID: 31004673 DOI: 10.1016/j.diabres.2019.04.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 02/05/2019] [Accepted: 04/12/2019] [Indexed: 11/29/2022]
Abstract
AIMS Neuromedin U (NMU), a highly conserved peptide, is implicated in energy homeostasis and is involved in regulating insulin secretion as a decretin hormone in animals. However, there have been no reports on the relationship between NMU and type 2 diabetes mellitus (T2DM). The aim of this study was to investigate circulating NMU concentrations in healthy subjects and T2DM patients and to evaluate the association between serum NMU levels and glucose-stimulated insulin secretion. METHODS We used ELISA to analyze NMU concentrations in blood samples from newly diagnosed T2DM patients (n = 57) and age-, sex- and BMI-matched healthy control subjects (n = 50). Anthropometric parameters, oral glucose tolerance, glycosylated hemoglobin, blood lipids, insulin sensitivity, and insulin secretion were measured. RESULTS No difference was observed in serum NMU levels between control subjects and newly diagnosed T2DM patients (p = 0.788). The oral glucose tolerance test (OGTT) results indicated that serum NMU concentrations did not change and did not correlate with insulin levels at fasting and 1 h, 2 h and 3 h after glucose load in both healthy controls and newly diagnosed T2DM patients. CONCLUSION Circulating NMU concentrations were similar in control subjects and newly diagnosed T2DM patients and were not associated with glucose-stimulated insulin secretion. Serum NMU is not a human decretin hormone and may not play a role in the pathogenesis of T2DM.
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Affiliation(s)
- Mingzhu Han
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China
| | - Yanhong Xu
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China
| | - Jing Yuan
- Department of Statistics, Shandong Institute of Business and Technology, Yantai 264005, China
| | - Yi Zhu
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China
| | - Jianhua Zhou
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China
| | - Lu Liu
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China
| | - Xiaohua Li
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China.
| | - Hongli Zhang
- Department of Endocrinology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, Shanghai 200137, China.
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15
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Pei R, DiMarco DM, Putt KK, Martin DA, Chitchumroonchokchai C, Bruno RS, Bolling BW. Premeal Low-Fat Yogurt Consumption Reduces Postprandial Inflammation and Markers of Endotoxin Exposure in Healthy Premenopausal Women in a Randomized Controlled Trial. J Nutr 2018; 148:910-916. [PMID: 29767743 PMCID: PMC5991203 DOI: 10.1093/jn/nxy046] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 02/14/2018] [Indexed: 12/19/2022] Open
Abstract
Background Metabolic endotoxemia is associated with obesity and contributes to postprandial inflammation. Objective We aimed to determine if low-fat yogurt consumption prevents postprandial inflammation and dysmetabolism in healthy women by inhibiting biomarkers of metabolic endotoxemia. Methods Premenopausal women defined as obese and nonobese [body mass index (BMI, in kg/m2) 30-40 and 18.5-27, respectively, n = 120] were randomly assigned to consume 339 g of low-fat yogurt (YN, yogurt nonobese; YO, yogurt obese) or 324 g of soy pudding (CN, control nonobese; CO, control obese) for 9 wk (n = 30/group). The intervention foods each supplied 330 kcal with 3 g fat, 66 g carbohydrate, and 4-6 g protein. At weeks 0 and 9, participants ingested 226 g of yogurt or 216 g of soy pudding before a meal providing 56-60 g fat, 82 g carbohydrate, and 28-30 g protein. Plasma soluble CD14 (sCD14), lipopolysaccharide-binding protein (LBP), LPS activity, interleukin-6 (IL-6), glucose, triglyceride, and insulin were measured hourly for 4 h to assess differences in postprandial responses between groups by 2-factor ANOVA. Results Premeal yogurt consumption prevented the postprandial decrease in sCD14 net incremental area under the curve (net iAUC) by 72% in obese individuals at week 0 (P = 0.0323). YN and YO had ≥40% lower net iAUC of LBP-to-sCD14 ratio and plasma IL-6 concentration than CN and CO, respectively (P < 0.05). CO had postprandial hyperglycemia which was not evident in YO; in contrast YN had 57% less postprandial hypoglycemia than did CN (P-interaction = 0.0013). After 9 wk of yogurt consumption, ΔAUC of LBP-to-sCD14 ratios of YO and YN were less than half of those of the control groups (P = 0.0093). Conclusion Yogurt consumption improved postprandial metabolism and biomarkers of metabolic endotoxemia in healthy premenopausal women. Premeal yogurt consumption is a feasible strategy to inhibit postprandial dysmetabolism and thus may reduce cardiometabolic risk. This trial was registered at clinicaltrials.gov as NCT01686204.
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Affiliation(s)
- Ruisong Pei
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT,Department of Food Science, University of Wisconsin-Madison, Madison, WI
| | - Diana M DiMarco
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT
| | - Kelley K Putt
- Department of Food Science, University of Wisconsin-Madison, Madison, WI
| | - Derek A Martin
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT,Department of Food Science, University of Wisconsin-Madison, Madison, WI
| | | | - Richard S Bruno
- Human Nutrition Program, The Ohio State University, Columbus, OH
| | - Bradley W Bolling
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT,Department of Food Science, University of Wisconsin-Madison, Madison, WI,Address correspondence to BWB (e-mail: )
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16
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Abstract
AIM Extracts from Ephedra species have been reported to be effective as antidiabetics. A previous in silico study predicted that ephedrine and five ephedrine derivatives could contribute to the described antidiabetic effect of Ephedra extracts by inhibiting dipeptidyl peptidase IV (DPP-IV). Finding selective DPP-IV inhibitors is a current therapeutic strategy for Type 2 diabetes mellitus management. Therefore, the main aim of this work is to experimentally determine whether these alkaloids are DPP-IV inhibitors. Materials & methods: The DPP-IV inhibition of Ephedra's alkaloids was determined via a competitive-binding assay. Then, computational analyses were used in order to find out the protein-ligand interactions and to perform a lead optimization. RESULTS Our results show that all six molecules are DPP-IV inhibitors, with IC50 ranging from 124 μM for ephedrine to 28 mM for N-methylpseudoephedrine. CONCLUSION Further computational analysis shows how Ephedra's alkaloids could be used as promising lead molecules for designing more potent and selective DPP-IV inhibitors.
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17
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Westberg-Rasmussen S, Starup-Linde J, Hermansen K, Holst JJ, Hartmann B, Vestergaard P, Gregersen S. Differential impact of glucose administered intravenously or orally on bone turnover markers in healthy male subjects. Bone 2017; 97:261-266. [PMID: 28126633 DOI: 10.1016/j.bone.2017.01.027] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 01/12/2017] [Accepted: 01/21/2017] [Indexed: 02/06/2023]
Abstract
BACKGROUND Patients with type-1 (T1D) and type-2 diabetes mellitus (T2D) have an increased risk of hip fracture. The underlying mechanisms may involve disturbances in the incretin hormones. Our aim was to clarify if glucose administration i.e. orally or intravenously differentially affects bone turnover markers in healthy males. METHODS 12 healthy males were included in a cross-over study consisting of three tests following an 8hour fast. First, an oral glucose tolerance test (OGTT) was performed. Subsequently, we carried out an isoglycemic intravenous glucose infusion (IIGI) that closely mimicked the glucose response curve to the oral glucose load. We analyzed blood samples for the bone turnover markers serum C-terminal telopeptide of type I collagen (s-CTX) and serum procollagen type I N propeptide (s-P1NP), as well as insulin, glucose, gastric inhibitory peptide (GIP), glucagon-like peptide-1 (GLP-1) and glucagon-like peptide-2 (GLP-2). Finally, eight of the twelve participants underwent a control experiment where they fasted for 3h (Control). RESULTS While OGTT induced a 50% reduction in s-CTX, only a ~30% reduction was seen during the IIGI and the Control. Neither intervention influenced s-P1NP. The concentration of insulin was highest during the OGTT. However, insulin was also increased significantly during the IIGI compared to the Control. Plasma concentrations of GIP, GLP-1 and GLP-2 were higher under the OGTT than during the IIGI and Control. A linear regression indicated that peak p-GIP significantly predicts nadir s-CTX (p=0.03), and that peak p-GIP could explain 34% of the variability in nadir s-CTX (adjusted R2=0.34). CONCLUSION This study indicates that glucose per se does not acutely affect bone turnover markers. However, gastrointestinal hormones, especially GIP, possibly in combination with hyperglycemia, may have an acute, uncoupling effect on bone turnover leading to a decrease in bone resorption but no change in bone formation.
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Affiliation(s)
| | - Jakob Starup-Linde
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Kjeld Hermansen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Jens Juul Holst
- Department of Biomedical Sciences and The NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences and The NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Peter Vestergaard
- Department of Endocrinology, Aalborg University Hospital, Aalborg, Denmark; Clinical Institute, Aalborg University and University Hospital, Aalborg, Denmark
| | - Søren Gregersen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
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Andres SF, Santoro MA, Mah AT, Keku JA, Bortvedt AE, Blue RE, Lund PK. Deletion of intestinal epithelial insulin receptor attenuates high-fat diet-induced elevations in cholesterol and stem, enteroendocrine, and Paneth cell mRNAs. Am J Physiol Gastrointest Liver Physiol 2015; 308:G100-11. [PMID: 25394660 PMCID: PMC4297856 DOI: 10.1152/ajpgi.00287.2014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The insulin receptor (IR) regulates nutrient uptake and utilization in multiple organs, but its role in the intestinal epithelium is not defined. This study developed a mouse model with villin-Cre (VC) recombinase-mediated intestinal epithelial cell (IEC)-specific IR deletion (VC-IR(Δ/Δ)) and littermate controls with floxed, but intact, IR (IR(fl/fl)) to define in vivo roles of IEC-IR in mice fed chow or high-fat diet (HFD). We hypothesized that loss of IEC-IR would alter intestinal growth, biomarkers of intestinal epithelial stem cells (IESC) or other lineages, body weight, adiposity, and glucose or lipid handling. In lean, chow-fed mice, IEC-IR deletion did not affect body or fat mass, plasma glucose, or IEC proliferation. In chow-fed VC-IR(Δ/Δ) mice, mRNA levels of the Paneth cell marker lysozyme (Lyz) were decreased, but markers of other differentiated lineages were unchanged. During HFD-induced obesity, IR(fl/fl) and VC-IR(Δ/Δ) mice exhibited similar increases in body and fat mass, plasma insulin, mRNAs encoding several lipid-handling proteins, a decrease in Paneth cell number, and impaired glucose tolerance. In IR(fl/fl) mice, HFD-induced obesity increased circulating cholesterol; numbers of chromogranin A (CHGA)-positive enteroendocrine cells (EEC); and mRNAs encoding Chga, glucose-dependent insulinotrophic peptide (Gip), glucagon (Gcg), Lyz, IESC biomarkers, and the enterocyte cholesterol transporter Scarb1. All these effects were attenuated or lost in VC-IR(Δ/Δ) mice. These results demonstrate that IEC-IR is not required for normal growth of the intestinal epithelium in lean adult mice. However, our findings provide novel evidence that, during HFD-induced obesity, IEC-IR contributes to increases in EEC, plasma cholesterol, and increased expression of Scarb1 or IESC-, EEC-, and Paneth cell-derived mRNAs.
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Affiliation(s)
- Sarah F. Andres
- 1Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - M. Agostina Santoro
- 1Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - Amanda T. Mah
- 2Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - J. Adeola Keku
- 1Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - Amy E. Bortvedt
- 1Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - R. Eric Blue
- 1Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - P. Kay Lund
- 1Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
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