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Sidibeh CO, Pereira MJ, Abalo XM, J Boersma G, Skrtic S, Lundkvist P, Katsogiannos P, Hausch F, Castillejo-López C, Eriksson JW. FKBP5 expression in human adipose tissue: potential role in glucose and lipid metabolism, adipogenesis and type 2 diabetes. Endocrine 2018; 62:116-128. [PMID: 30032404 PMCID: PMC6153563 DOI: 10.1007/s12020-018-1674-5] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [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: 03/16/2018] [Accepted: 07/02/2018] [Indexed: 12/12/2022]
Abstract
PURPOSE Here, we explore the involvement of FKBP51 in glucocorticoid-induced insulin resistance (IR) in human subcutaneous adipose tissue (SAT), including its potential role in type 2 diabetes (T2D). Moreover, we assess the metabolic effects of reducing the activity of FKBP51 using the specific inhibitor SAFit1. METHODS Human SAT was obtained by needle biopsies of the lower abdominal region. FKBP5 gene expression was assessed in fresh SAT explants from a cohort of 20 T2D subjects group-wise matched by gender, age and BMI to 20 non-diabetic subjects. In addition, human SAT was obtained from non-diabetic volunteers (20F/9M). SAT was incubated for 24 h with or without the synthetic glucocorticoid dexamethasone and SAFit1. Incubated SAT was used to measure the glucose uptake rate in isolated adipocytes. RESULTS FKBP5 gene expression levels in SAT positively correlated with several indices of IR as well as glucose area under the curve during oral glucose tolerance test (r = 0.33, p < 0.05). FKBP5 gene expression levels tended to be higher in T2D subjects compared to non-diabetic subjects (p = 0.088). Moreover, FKBP5 gene expression levels were found to inversely correlate with lipolytic, lipogenic and adipogenic genes. SAFit1 partly prevented the inhibitory effects of dexamethasone on glucose uptake. CONCLUSIONS FKBP5 gene expression in human SAT tends to be increased in T2D subjects and is related to elevated glucose levels. Moreover, FKBP5 gene expression is inversely associated with the expression of lipolytic, lipogenic and adipogenic genes. SAFit1 can partly prevent glucose uptake impairment by glucocorticoids, suggesting that FKBP51 might be a key factor in glucocorticoid-induced IR.
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Affiliation(s)
- Cherno O Sidibeh
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Maria J Pereira
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Xesus M Abalo
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Gretha J Boersma
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Stanko Skrtic
- AstraZeneca R&D, Mölndal, Sweden
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Per Lundkvist
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | | | - Felix Hausch
- Institute of Organic Chemistry and Biochemistry, Technical University Darmstadt, Darmstadt, Germany
| | | | - Jan W Eriksson
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
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Hage N, Howard T, Phillips C, Brassington C, Overman R, Debreczeni J, Gellert P, Stolnik S, Winkler GS, Falcone FH. Structural basis of Lewis(b) antigen binding by the Helicobacter pylori adhesin BabA. Sci Adv 2015; 1:e1500315. [PMID: 26601230 PMCID: PMC4643811 DOI: 10.1126/sciadv.1500315] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/03/2015] [Indexed: 05/09/2023]
Abstract
Helicobacter pylori is a leading cause of peptic ulceration and gastric cancer worldwide. To achieve colonization of the stomach, this Gram-negative bacterium adheres to Lewis(b) (Le(b)) antigens in the gastric mucosa using its outer membrane protein BabA. Structural information for BabA has been elusive, and thus, its molecular mechanism for recognizing Le(b) antigens remains unknown. We present the crystal structure of the extracellular domain of BabA, from H. pylori strain J99, in the absence and presence of Le(b) at 2.0- and 2.1-Å resolutions, respectively. BabA is a predominantly α-helical molecule with a markedly kinked tertiary structure containing a single, shallow Le(b) binding site at its tip within a β-strand motif. No conformational change occurs in BabA upon binding of Le(b), which is characterized by low affinity under acidic [K D (dissociation constant) of ~227 μM] and neutral (K D of ~252 μM) conditions. Binding is mediated by a network of hydrogen bonds between Le(b) Fuc1, GlcNAc3, Fuc4, and Gal5 residues and a total of eight BabA amino acids (C189, G191, N194, N206, D233, S234, S244, and T246) through both carbonyl backbone and side-chain interactions. The structural model was validated through the generation of two BabA variants containing N206A and combined D233A/S244A substitutions, which result in a reduction and complete loss of binding affinity to Le(b), respectively. Knowledge of the molecular basis of Le(b) recognition by BabA provides a platform for the development of therapeutics targeted at inhibiting H. pylori adherence to the gastric mucosa.
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Affiliation(s)
- Naim Hage
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Tina Howard
- Discovery Sciences, Innovative Medicines and Early Development, AstraZeneca R&D, Alderley Park, Cheshire SK10 4TG, UK
- Corresponding author. E-mail: (T.H.); (F.H.F.)
| | - Chris Phillips
- Discovery Sciences, Innovative Medicines and Early Development, AstraZeneca R&D, Darwin Building, 310 Cambridge Science Park, Milton Road, Cambridge CB4 0WG, UK
| | - Claire Brassington
- Discovery Sciences, Innovative Medicines and Early Development, AstraZeneca R&D, Alderley Park, Cheshire SK10 4TG, UK
| | - Ross Overman
- Discovery Sciences, Innovative Medicines and Early Development, AstraZeneca R&D, Alderley Park, Cheshire SK10 4TG, UK
| | - Judit Debreczeni
- Discovery Sciences, Innovative Medicines and Early Development, AstraZeneca R&D, Darwin Building, 310 Cambridge Science Park, Milton Road, Cambridge CB4 0WG, UK
| | - Paul Gellert
- Pharmaceutical Development, AstraZeneca R&D, Charter Way, Macclesfield, Cheshire SK10 2NA, UK
| | - Snow Stolnik
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - G. Sebastiaan Winkler
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Franco H. Falcone
- School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK
- Corresponding author. E-mail: (T.H.); (F.H.F.)
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