1
|
Aggarwal S, Tanwar N, Singh A, Munde M. Formation of Protamine and Zn-Insulin Assembly: Exploring Biophysical Consequences. ACS OMEGA 2022; 7:41044-41057. [PMID: 36406544 PMCID: PMC9670714 DOI: 10.1021/acsomega.2c04419] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
The insulin-protamine interaction is at the core of the mode of action in many insulin formulations (Zn + insulin + protamine) and to treat diabetes, in which protamine is added to the stable form of hexameric insulin (Zn-insulin). However, due to the unavailability of quantitative data and a high-resolution structure, the binding mechanism of the insulin-protamine complex remains unknown. In this study, it was observed that Zn-insulin experiences destabilization as observed by the loss of secondary structure in circular dichroism (CD), and reduction in thermal stability in melting study, upon protamine binding. In isothermal titration calorimetry (ITC), it was found that the interactions were mostly enthalpically driven. This is in line with the positive ΔC m value (+880 cal mol-1), indicating the role of hydrophilic interactions in the complex formation, with the exposure of hydrophobic residues to the solvent, which was firmly supported by the 8-anilino-1-naphthalene sulfonate (ANS) binding study. The stoichiometry (N) value in ITC suggests the multiple insulin molecules binding to the protamine chain, which is consistent with the picture of the condensation of insulin in the presence of protamine. Atomic force microscopy (AFM) suggested the formation of a heterogeneous Zn-insulin-protamine complex. In fluorescence, Zn-insulin experiences strong Tyr quenching, suggesting that the location of the protamine-binding site is near Tyr, which is also supported by the molecular docking study. Since Tyr is critical in the stabilization of insulin self-assembly, its interaction with protamine may impair insulin's self-association ability and thermodynamic stability while at the same time promoting its flexible conformation desired for better biological activity.
Collapse
|
2
|
Archontogeorgis K, Voulgaris A, Nena E, Zissimopoulos A, Bouloukaki I, Schiza SE, Steiropoulos P. Vitamin D Levels in Patients with Overlap Syndrome, Is It Associated with Disease Severity? J Pers Med 2022; 12:jpm12101693. [PMID: 36294836 PMCID: PMC9605178 DOI: 10.3390/jpm12101693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 11/16/2022] Open
Abstract
Background: The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) has been defined as overlap syndrome (OVS). Recently, a link between OSA, COPD and Vitamin D (Vit D) serum concentration was reported, however, evidence regarding Vit D status in patients with OVS is scarce. The aim of the present study was to evaluate Vit D serum levels and to explore the association of those levels with anthropometric, pulmonary function and sleep parameters in patients with OVS. Methods: Vit D serum levels were measured in patients diagnosed with OVS, as confirmed by overnight polysomnography and pulmonary function testing. Results: A total of 90 patients (79 males and 11 females) were included in the analysis. The patients were divided into three groups matched for age, gender, and BMI: the control group that included 30 patients (27 males and 3 females), the OSA group that included 30 patients (26 males and 4 females), and the OVS group that included 30 patients (26 males and 4 females). Patients with OVS exhibited decreased serum 25(OH)D levels compared with OSA patients and controls (14.5 vs. 18.6 vs. 21.6 ng/mL, p < 0.001). In the OVS group, multiple linear regression analysis identified AHI and FEV1, as predictors of serum 25(OH)D levels (p = 0.041 and p = 0.038, respectively). Conclusions: Lower Vit D levels have been observed in patients with OVS compared with OSA patients and non-apneic controls, indicating an increased risk of hypovitaminosis D in this population which might be associated with disease severity.
Collapse
Affiliation(s)
- Kostas Archontogeorgis
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Athanasios Voulgaris
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Evangelia Nena
- Laboratory of Social Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Athanasios Zissimopoulos
- Laboratory of Nuclear Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Izolde Bouloukaki
- Sleep Disorders Unit, Department of Respiratory Medicine, Medical School, University of Crete, 71110 Heraklion, Greece
| | - Sophia E. Schiza
- Sleep Disorders Unit, Department of Respiratory Medicine, Medical School, University of Crete, 71110 Heraklion, Greece
| | - Paschalis Steiropoulos
- MSc Program in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece
- Correspondence: ; Tel.: +30-551352096
| |
Collapse
|
3
|
Vacelet L, Hupin D, Pichot V, Celle S, Court-Fortune I, Thomas T, Garcin A, Barthélémy JC, Gozal D, Roche F. Insulin Resistance and Type 2 Diabetes in Asymptomatic Obstructive Sleep Apnea: Results of the PROOF Cohort Study After 7 Years of Follow-Up. Front Physiol 2021; 12:650758. [PMID: 34393806 PMCID: PMC8355896 DOI: 10.3389/fphys.2021.650758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 07/05/2021] [Indexed: 11/25/2022] Open
Abstract
The aim of the study was to assess potential associations between obstructive sleep apnea (OSA) and the occurrence of diabetes mellitus and insulin resistance in the elderly. Nondiabetic volunteers (n = 549) with undiagnosed or untreated asymptomatic OSA (66.2+/−1 years at the inclusion) were evaluated as an ancillary study of the PROOF cohort study (n = 1,011). After 7 years follow-up, 494 subjects underwent assessment of fasting insulin and glucose levels. OSA was defined by an apnea-hypopnea index (AHI) of ≥15/h using polygraphy. Diabetes mellitus was defined by a fasting glucose ≥ 1.26 g/L and/or when requiring pharmacological treatment, while insulin resistance corresponded to HOMA-IR ≥ 2. Asymptomatic OSA subjects (men or women) did not display increased risk of incident diabetes (2.8 vs. 3.9%, p = 0.51). However, there was a greater frequency of insulin resistance in subjects with severe OSA (AHI > 30) [OR 2.21; 95% CI (1.22–4.02); p = 0.009]. Furthermore, multiple logistic regression showed that triglycerides levels [OR 1.61; 95% CI (1.10–2.36); p = 0.01] and fasting glycaemia [OR 4.69; 95% CI (1.12–192.78); p = 0.04], but not AHI or oxyhemoglobin desaturation index were independently associated with higher rate of insulin resistance. The deleterious metabolic effect of asymptomatic OSA in the population may be indirectly mediated via perturbations in lipids, and is particularly likely to become manifest in severe apneic subjects with higher glycemic levels.
Collapse
Affiliation(s)
- Laurine Vacelet
- Service de Physiologie Clinique et de l'Exercice, CHU Saint Etienne, Saint Etienne Cedex, France.,Sainbiose DVH U1059 Inserm, Faculté de Médecine J Lisfranc, Université Jean Monnet, Saint Etienne Cedex, France
| | - David Hupin
- Service de Physiologie Clinique et de l'Exercice, CHU Saint Etienne, Saint Etienne Cedex, France.,Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France
| | - Vincent Pichot
- Service de Physiologie Clinique et de l'Exercice, CHU Saint Etienne, Saint Etienne Cedex, France.,Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France
| | - Sébastien Celle
- Service de Physiologie Clinique et de l'Exercice, CHU Saint Etienne, Saint Etienne Cedex, France.,Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France
| | - Isabelle Court-Fortune
- Sainbiose DVH U1059 Inserm, Faculté de Médecine J Lisfranc, Université Jean Monnet, Saint Etienne Cedex, France
| | - Thierry Thomas
- Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France.,Service de Rhumatologie, CHU Saint Etienne, Saint Etienne Cedex, France
| | - Arnauld Garcin
- Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France.,URCIP, CHU Saint Etienne, Saint Etienne Cedex, France
| | - Jean-Claude Barthélémy
- Service de Physiologie Clinique et de l'Exercice, CHU Saint Etienne, Saint Etienne Cedex, France.,Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France
| | - David Gozal
- Department of Child Health, MU Women's and Children's Hospital, Columbia, MO, United States
| | - Frédéric Roche
- Service de Physiologie Clinique et de l'Exercice, CHU Saint Etienne, Saint Etienne Cedex, France.,Service de Pneumologie, CHU Saint Etienne, Saint Etienne Cedex, France
| |
Collapse
|
4
|
Archontogeorgis K, Papanas N, Rizos EC, Nena E, Zissimopoulos A, Tsigalou C, Voulgaris A, Mikhailidis DP, Elisaf MS, Froudarakis ME, Steiropoulos P. Reduced Serum Vitamin D Levels Are Associated with Insulin Resistance in Patients with Obstructive Sleep Apnea Syndrome. ACTA ACUST UNITED AC 2019; 55:medicina55050174. [PMID: 31137600 PMCID: PMC6572623 DOI: 10.3390/medicina55050174] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 03/26/2019] [Accepted: 05/13/2019] [Indexed: 01/03/2023]
Abstract
Background and objectives: Obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular and metabolic risk factors, such as insulin resistance. Furthermore, OSAS has been associated with decreased levels of vitamin D (Vit D). The aim of the study was to assess the association between Vit D levels (expressed as 25(OH)D serum levels) and insulin resistance in patients with OSAS. Materials and Methods: Serum 25(OH)D levels were measured in consecutive subjects who had undergone polysomnography and pulmonary function testing. OSAS patients were divided into those with (homeostatic model assessment [HOMA-IR] ≥ 2) and without insulin resistance (HOMA-IR < 2). Results: Overall, 92 patients (81 males) were included in the study. OSAS patients with insulin resistance significantly differed from those without insulin resistance in terms of the body-mass index (BMI) (36.3 ± 5.8 compared to 32 ± 5.6 kg/m2, respectively, p = 0.001), apnoea-hypopnoea index (AHI) (57.4 ± 28.9 compared to 40.9 ± 27.9 events/h, respectively, p = 0.009) and indices of hypoxia during sleep. Patients with OSAS and insulin resistance had lower levels of serum 25 (OH) D compared with OSAS but without insulin resistance (19.3 ± 11.5 vs 26.7 ± 12.2 ng/mL, respectively, p = 0.005). Regression analysis demonstrated a negative association of 25(OH)D levels (β = −0.048, odds ratio [OR]: 0.953, 95% confidence interval [CI]: 0.913–0.995, p = 0.030) and a positive association of BMI (β = 0.110, OR: 1.116, 95% CI: 1.007–1.237, p = 0.036) with insulin resistance. Conclusions: Vit D insufficiency was significantly more frequent among OSAS patients with insulin resistance. Both low 25(OH)D levels and high BMI were associated with the risk of insulin resistance in this population.
Collapse
Affiliation(s)
- Kostas Archontogeorgis
- MSc Programme in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Nikolaos Papanas
- Diabetes Centre, Second Department of Internal Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Evangelos C Rizos
- Department of Internal Medicine, School of Medicine, University of Ioannina, 45110 Ioannina, Greece.
| | - Evangelia Nena
- Laboratory of Hygiene and Environmental Protection, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Athanasios Zissimopoulos
- Laboratory of Nuclear Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Christina Tsigalou
- Laboratory of Microbiology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Athanasios Voulgaris
- MSc Programme in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Dimitri P Mikhailidis
- Department of Clinical Biochemistry, Royal Free Hospital Campus, University College London Medical School, University College London (UCL), NW3 2QG London, UK.
| | - Moses S Elisaf
- Department of Internal Medicine, School of Medicine, University of Ioannina, 45110 Ioannina, Greece.
| | - Marios E Froudarakis
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| | - Paschalis Steiropoulos
- MSc Programme in Sleep Medicine, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
- Department of Pneumonology, Medical School, Democritus University of Thrace, 68100 Alexandroupolis, Greece.
| |
Collapse
|
5
|
Aurora RN, Punjabi NM. Obstructive Sleep Apnea, Sleepiness, and Glycemic Control in Type 2 Diabetes. J Clin Sleep Med 2019; 15:749-755. [PMID: 31053205 DOI: 10.5664/jcsm.7768] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 01/16/2019] [Indexed: 01/21/2023]
Abstract
STUDY OBJECTIVES Self-reported sleepiness is common in patients with obstructive sleep apnea (OSA) and is being increasingly recognized as an effect modifier of the association between OSA and cardiovascular outcomes. However, data on whether sleepiness modifies the association between OSA and glycemic outcomes are lacking. The current study sought to characterize the association between glycemic control and sleepiness in people with OSA and type 2 diabetes. METHODS Adults with non-insulin requiring type 2 diabetes and undiagnosed moderate to severe OSA were recruited from the community. Demographic data, Epworth Sleepiness Scale (ESS), hemoglobin A1c (HbA1c), as well a type III home sleep test were obtained. The association between self-reported sleepiness and glycemic control was examined using quantile regression. RESULTS The study cohort included 311 participants with 56% of the sample being men. Stratified analyses by sex demonstrated that self-reported sleepiness was associated with a higher HbA1c level, but this association was present only in men with a body mass index (BMI) < 35 kg/m2. Mean HbA1c levels were higher by 0.57% (95% confidence interval: 0.11, 1.02) in men with an ESS ≥ 11 compared to men with an ESS < 11. No such association was observed in men with a BMI ≥ 35 kg/m2 or in women of any BMI category. CONCLUSIONS The association between self-reported sleepiness and glycemic control in people with type 2 diabetes and moderate to severe OSA varies a function of BMI and sex. The noted differences in association should be considered when assessing possible treatment effects of therapy for OSA on metabolic outcomes.
Collapse
Affiliation(s)
- R Nisha Aurora
- Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey
| | - Naresh M Punjabi
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland.,Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland
| |
Collapse
|
6
|
Cardiovascular Risk Assessment in a Cohort of Newly Diagnosed Patients with Obstructive Sleep Apnea Syndrome. Cardiol Res Pract 2018; 2018:6572785. [PMID: 29707392 PMCID: PMC5863345 DOI: 10.1155/2018/6572785] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/24/2018] [Indexed: 12/04/2022] Open
Abstract
Objectives Obstructive sleep apnea syndrome (OSAS) is associated with increased cardiovascular morbidity and mortality. The aim of this study was to assess whether the 10-year risk for cardiovascular disease in newly diagnosed patients with OSAS is increased. Materials and Methods Recently diagnosed, with polysomnography, consecutive OSAS patients were included. The Systematic Coronary Risk Evaluation (SCORE) and the Framingham Risk Score (FRS) were used to estimate the 10-year risk for cardiovascular disease. Results Totally, 393 individuals (73.3% males), scheduled to undergo a polysomnographic study with symptoms indicative of OSAS, were enrolled. According to apnea-hypopnea index (AHI), subjects were divided in four groups: mild OSAS (AHI 5–14.9/h) was diagnosed in 91 patients (23.2%), moderate OSAS (AHI 15–29.9/h) in 58 patients (14.8%), severe OSAS (AHI > 30/h) in 167 patients (42.5%), while 77 individuals (19.6%) had an AHI < 5/h and served as controls. Increased severity of OSAS was associated with increased SCORE (p < 0.001) and FRS values (p < 0.001). More specifically, a significant correlation was observed both between AHI and SCORE (r=0.251, p < 0.001) and AHI and FRS values (r=0.291, p < 0.001). Furthermore, a negative correlation was observed between FRS values and sleep efficiency (r=−0.224, p=0.006). Conclusions The 10-year risk for cardiovascular morbidity and mortality seems to increase with severity of OSAS. Physicians should bear this finding in mind, in order to seek for and consecutively eliminate risk factors for cardiovascular disease and to prevent future cardiovascular events in OSAS patients.
Collapse
|