Z8 - A Microphysiological Interface of Skeletal Myobundles and Inflamed Adipose Tissue for Recapitulating Muscle Dysfunction in an Obese Microenvironment

Friday, October 10, 2025

10:00 AM - 11:00 AM PDT

Location: Exhibit Hall F, G & H

Presenting Author(s)

Seunggyu Kim, PhD

Assistant Professor
Korea University, United States

Primary Investigator(s)

Seunggyu Kim, PhD

Assistant Professor
Korea University, United States

Co-Author(s)

TC

Tianxin Cao

Post-doc
Boerhinger Ingelheim, United States
CW

Curtis Warren

Principal Scientist
Boerhinger Ingelheim, United States

Last Author(s)

RK

Roger Kamm

Professor
Massachusetts Institute of Technology, United States

Introduction: : Obesity is a chronic metabolic condition associated with systemic low-grade inflammation that impairs various tissues, including skeletal muscle. Muscle dysfunction in obesity contributes to metabolic inflexibility, reduced mobility, and diminished quality of life. This dysfunction is driven by inflammatory cytokines secreted from hypertrophied adipocytes and infiltrating macrophages within visceral and intermuscular adipose depots. These tissues release bioactive factors—such as TNF-α, IL-6, and MCP-1—that disrupt muscle homeostasis via paracrine signaling, resulting in insulin resistance, mitochondrial dysfunction, and atrophy.
Despite growing awareness of adipose–muscle crosstalk, physiologically relevant in vitro models that capture this inter-tissue signaling remain scarce. Microphysiological systems (MPS) offer a promising solution by enabling precise control over multicellular interactions. Previous MPS studies have explored neuromuscular junctions or vascular integration, but none have directly modeled the interplay between inflamed adipose tissue and engineered human skeletal muscle.
To address this gap, we engineered a human-derived MPS that integrates 3D engineered muscle tissue (EMT) with an inflamed adipose–macrophage co-culture (IAMC). HiPSC-derived myoblasts formed 3D contractile myobundles on micropillar devices. IAMCs, mimicking obese adipose inflammation, were created by co-culturing TNF-α-treated adipocytes with pro-inflammatory (M1) macrophages. Using a Transwell-based configuration, the two tissues communicated via soluble factors, enabling paracrine interaction without physical contact. This biomimetic system facilitates both functional readouts and molecular interrogation of obesity-induced muscle dysfunction, providing a physiologically relevant platform to study disease mechanisms and evaluate potential therapeutic strategies.

Materials and

Methods: : To model obesity-associated muscle dysfunction, we developed a human MPS integrating EMT with an IAMC using a Transwell-based paracrine signaling interface. EMTs were constructed by embedding hiPSC-derived myoblasts in a collagen–Matrigel hydrogel and casting the mixture between two micropillars of a custom-fabricated PDMS device. The pillars, designed with elliptical cross-sections and wide caps to prevent detachment, enabled real-time quantification of contractile force through their deflection during electrical stimulation.
Myoblasts differentiated on-device for 10 days formed compact, aligned 3D myobundles exhibiting sarcomeric structure and maturation markers. IAMCs were independently prepared by co-culturing TNF-α-treated human adipose stem cells-derived adipocytes with THP-1 monocytes-derived M1 macrophages. To establish the paracrine interface, EMT-bearing micropillar devices on day 8 of differentiation were transferred onto Transwell inserts, positioned above the IAMC wells, and co-cultured for an additional 2 days. Soluble inflammatory mediators secreted by IAMCs diffused across the membrane to interact with the muscle tissues without direct cell contact. This modular setup enabled controlled exposure to inflammatory cues and independent pre-conditioning of each tissue component.
On day 10, pillar deflection induced by electrical stimulation was quantified via image analysis to assess the contractile performance of EMTs. Cytokine arrays of conditioned media and transcriptomic profiling of EMTs were performed to characterize the inflammatory and metabolic consequences of IAMC exposure.

Results, Conclusions, and Discussions:: The developed micropillar device enabled the successful formation of compact and contractile myobundles expressing mature myotube markers, including sarcomeric α-actinin and slow myosin heavy chain. When co-cultured with IAMC, these EMTs exhibited drastic reductions in contractile force (~80%) and contraction velocity (~84%) compared to controls. This suggests that soluble inflammatory signals from the IAMC impair muscle function, mimicking the contractile deficits observed in obesity.
Cytokine analysis of conditioned media from the EMT-IAMC interface revealed elevated levels of key inflammatory mediators including CCL5, IL-6, IL-8, and CXCL5, all of which are known contributors to metabolic dysfunction and muscle inflammation. Gene expression profiling of EMTs further supported this inflammatory influence: upregulated genes such as SLC27A1 and PIK3R1 were linked to fatty acid transport and insulin resistance, while downregulated genes such as SLC2A1 and HK2 suggested impaired glycolysis and glucose uptake. These changes collectively indicate a shift in metabolic substrate preference towards fatty acid utilization—a known feature of insulin-resistant muscle.
Importantly, the spatially separated co-culture setup allowed for paracrine signaling while preserving the independent analysis of both tissues, enabling accurate assessment of cytokine-driven effects. The force measurements of EMTs, validated by finite element–derived stiffness values, provided quantitative insight into functional impairment under inflammatory conditions.
Overall, the study presents a physiologically relevant, modular human MPS that recapitulates obesity-associated muscle dysfunction via adipose–muscle paracrine interaction. This platform not only facilitates mechanistic investigation into the role of inflamed adipose tissue in muscle pathology but also serves as a promising tool for therapeutic screening in metabolic disease contexts. By integrating functional, molecular, and biochemical analyses, this system offers a powerful approach to understand and counteract the impact of obesity on skeletal muscle health.

Acknowledgements and/or References (Optional): : The authors would like to thank all the members of the Kamm Lab for their valuable feedback during the project. This work was supported by Boehringer-Ingelheim, the Korea University Grants, and the National Research Foundation of Korea (RS-2025-02283193)