Characterization of diabetes-related biomechanical and structural alterations in human deep fasciae using atomic force microscopy and multimodal multiphoton imaging

Ugwoke, Chiedozie Kenneth (author), Furlani, Borut (author), Hadraba, Daniel (author), Janáček, Jiří (author), Cvetko, Erika (author), Jorgačevski, Jernej (author), Kreft, Marko (author), Zorec, Robert (author), Saudek, František (author), Umek, Nejc (author)

Background: Type 2 diabetes mellitus (T2DM) is associated with connective-tissue complications, but effects on human deep fascia remain poorly understood. This study employed atomic force microscopy (AFM) nanoindentation and multiphoton imaging to quantify region-specific biomechanical and structural changes of deep fasciae in T2DM. Methods: Fascia lata, thoracolumbar fascia, and plantar fascia from 17 T2DM and 17 control male deceased (<24 h post-mortem) donors were analyzed. AFM was used to quantify nanoscale stiffness (Young’s modulus) under hydrated conditions. Label-free multiphoton microscopy comprising Second Harmonic Generation (SHG), Two-Photon Excited Fluorescence (TPEF), and Fluorescence Lifetime Imaging Microscopy (FLIM) was used to assess collagen organization, autofluorescence, and fluorescence decay kinetics. Results: AFM revealed significantly increased stiffness in diabetic plantar fascia (87 ± 3.1 vs 40 ± 1.2 kPa, p = 0.004) and fascia lata (28 ± 1.2 vs 16 ± 0.5 kPa, p < 0.001) compared to controls, while thoracolumbar fascia stiffness did not differ significantly between groups. Stiffness changes showed no significant association with age or body mass index. SHG forward-to-backward ratios did not differ significantly between groups, suggesting preserved collagen supramolecular organization. However, TPEF ratios were significantly elevated in diabetic plantar fascia and fascia lata, suggesting increased accumulation of autofluorescent species. FLIM revealed a significant decrease in mean fluorescence lifetime (τₘ) in diabetic plantar fascia, indicative of altered collagen microenvironment, possibly due to glycation or oxidative modifications. Conclusion: T2DM induces site-specific biomechanical stiffening and biochemical remodeling of human deep fascia, particularly in load-bearing regions. These changes suggest mechanisms involving glycation and oxidative stress, providing mechanistic insights into musculoskeletal complications associated with diabetic fasciopathy.

• Language: English
• Keywords: advanced glycation end-products, atomic force microscopy, deep fascia, extracellular matrix remodeling, multiphoton imaging, type 2 diabetes mellitus
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine; BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 11 str.
• Numbering: Vol. 98, art. 103209
• PID: 20.500.12556/RUL-182020
• UDC: 616
• ISSN on article: 1532-3072
• DOI: 10.1016/j.tice.2025.103209
• COBISS.SI-ID: 258042627
• Publication date in RUL: 22.04.2026

Record is a part of a journal

• Title: Tissue & cell
• Shortened title: Tissue cell
• Publisher: Elsevier
• ISSN: 1532-3072
• COBISS.SI-ID: 175317763

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: napredni končni produkti glikacije, mikroskopija atomskih sil, globoka fascija, preoblikovanje zunajceličnega matriksa, večfotonsko slikanje, sladkorna bolezen tipa 2