Association of amino acids and parameters of bone metabolism with endothelial dysfunction and vasculopathic changes in limited systemic sclerosis

Philipp Jud; Andreas Meinitzer; Heimo Strohmaier; Behrouz Arefnia; Gernot Wimmer; Barbara Obermayer-Pietsch; Vasile Foris; Gabor Kovacs; Balazs Odler; Florentine Moazedi-Fürst; Marianne Brodmann; Franz Hafner

doi:10.3389/fmed.2023.1193121

Association of amino acids and parameters of bone metabolism with endothelial dysfunction and vasculopathic changes in limited systemic sclerosis

Front Med (Lausanne). 2023 Jun 23:10:1193121. doi: 10.3389/fmed.2023.1193121. eCollection 2023.

Authors

Affiliations

¹ Division of Angiology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
² Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria.
³ Center of Medical Research (ZMF), Medical University of Graz, Graz, Austria.
⁴ Division of Restorative Dentistry, Endodontics, Periodontology and Prosthodontics, Department of Dental Medicine and Oral Health, Medical University of Graz, Graz, Austria.
⁵ Division of Endocrinology and Diabetology, Department of Internal Medicine, Endocrinology Lab Platform, Medical University of Graz, Graz, Austria.
⁶ Division of Pulmonology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
⁷ Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria.
⁸ Division of Nephrology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
⁹ Division of Rheumatology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.

Abstract

Objectives: Pathways contributing to endothelial dysfunction in patients with limited cutaneous systemic sclerosis (lcSSc) are largely unknown. The aim of this study was to investigate potential associations of amino acids and parameters of bone metabolism with endothelial dysfunction and vasculopathy-related changes in patients with lcSSc and early-stage vasculopathy.

Methods: Amino acids, calciotropic parameters, including 25-hydroxyvitamin D and parathyroid hormone (PTH), and bone turnover parameters, including osteocalcin and N-terminal peptide of procollagen-3 (P3NP), were measured in 38 lcSSc patients and 38 controls. Endothelial dysfunction was assessed by biochemical parameters, pulse-wave analysis, flow-mediated and nitroglycerine-mediated dilation. Additionally, vasculopathy-related and SSc-specific clinical changes including capillaroscopic, skin, renal, pulmonary, gastrointestinal and periodontal parameters were recorded.

Results: No significant differences in amino acids, calciotropic and bone turnover parameters were observed between lcSSc patients and controls. In patients with lcSSc, several significant correlations were found between selected amino acids, parameters of endothelial dysfunction, vasculopathy-related and SSc-specific clinical changes (all with p < 0.05). In addition, significant correlations were observed between PTH and 25-hydroxyvitamin D with homoarginine, and between osteocalcin, PTH and P3NP with modified Rodnan skin score and selected periodontal parameters (all with p < 0.05). Vitamin D deficiency defined as 25-hydroxyvitamin D < 20 ng/ml was associated with the presence of puffy finger (p = 0.046) and early pattern (p = 0.040).

Conclusion: Selected amino acids may affect endothelial function and may be associated to vasculopathy-related and clinical changes in lcSSc patients, while the association with parameters of bone metabolism seems to be minor.

Keywords: amino acids; bone metabolism; endothelial dysfunction; systemic sclerosis; vitamin D.