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bioRxiv · 10.64898/2026.06.01.729187

Hyaluronic Acid Plays Differential Molecular Weight and Concentration Dependent Pathway Centric Changes to Human Lung Derived Microvascular Endothelial Cells in Culture

Abstract

BackgroundHyaluronan (HA) is a major extracellular matrix glycosaminoglycan that regulates vascular integrity and immune signaling in the lung. Its biological effects are strongly size-dependent, with high-molecular-weight HA (HMW-HA) generally protective and low-molecular-weight HA (LMW-HA) pro-inflammatory. However, how different HA sizes and concentrations globally remodel endothelial cell signaling remains poorly understood. MethodsHuman lung microvascular endothelial cells (HULEC-5a) were treated with physiologic (200 ng/mL) or supraphysiologic (1 {micro}g/mL) concentrations of LMW-, medium-molecular-weight (MMW-), or HMW-HA. Cell viability was confirmed by LDH assay. Quantitative proteomics with downstream Ingenuity Pathway Analysis (IPA) was used to profile HA-induced signaling networks. ResultsProteomic analysis revealed a conserved HA-response signature across all conditions involving cell cycle regulation, senescence, and immune modulation, with distinct size-and dose-dependent differences. At supraphysiologic concentrations, HMW-HA suppressed proliferative and inflammatory pathways, consistent with a protective, quiescent phenotype. LMW-HA induced the broadest stress-associated proteomic changes, consistent with its role as a damage-associated molecular pattern. Unexpectedly, physiologic MMW-HA elicited the strongest responses, driving metabolic and cytoskeletal pathways including insulin signaling and Rho GTPase activity. Network analysis highlighted 176 overlapping pathways across HA treatments, with unique contributions of LMW- and HMW-HA to stress- versus barrier-stabilizing signaling, respectively. ConclusionHA is not a passive structural molecule but an active regulator of endothelial signaling, with effects shaped by both molecular weight and concentration. Our findings identify a distinct role for MMW-HA at physiologic levels and highlight how HA fragmentation and accumulation may contribute to endothelial dysfunction in lung injury, with implications for targeted HA-based therapies.

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BibTeXRIS

Mobley, J. A., Kojima, K., Yellumahanththi, S.. 2026-06-03. Hyaluronic Acid Plays Differential Molecular Weight and Concentration Dependent Pathway Centric Changes to Human Lung Derived Microvascular Endothelial Cells in Culture. https://doi.org/10.64898/2026.06.01.729187

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