Biology subjects

Bae, S. H.

Publications and source records attributed to Bae, S. H..

3 recordsLinked to original sources

bioRxiv2026

Pirfenidone improves adipose dysfunction and obesity-driven steatohepatitis via mTORC1 signaling

Obesity-driven metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are shaped by depot-specific adipose tissue dysfunction, including maladaptive expansion and visceral adipose tissue (VAT) fibrosis. Pirfenidone, an anti-fibrotic agent, improves experimental liver disease. However, its actions on adipose depots and adipose-liver crosstalk remain unclear. Here, we identify pirfenidone as a modulator of mechanistic target of rapamycin complex 1 (mTORC1)-dependent adipose tissue remodeling with divergent outputs in subcutaneous and visceral fat. In diet-induced obese MASH mice, pirfenidone decreased subcutaneous adipose tissue (SAT), inhibiting mTORC1-driven lipogenesis and enhancing oxidative lipid metabolism. Pirfenidone attenuated VAT fibrosis by suppressing an mTORC1-mothers against decapentaplegic homolog 3 (SMAD3)-yes-associated protein (YAP) axis and extracellular matrix gene programs. Pirfenidone also lowered hepatic triglycerides, improved steatosis and fibrosis, reduced hepatic mTORC1 activity. Conditioned medium from fibrotic adipocytes induced lipogenic, inflammatory, and pro-fibrotic programs in AML12, which effects that were blunted by pirfenidone. These data reveal adipose tissue-centered actions of pirfenidone that link mTORC1 remodeling to improved obesity-associated liver disease.

molecular biology↗

bioRxiv2022

Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics in vivo

Measuring cellular and tissue mechanics inside intact living organisms is essential for interrogating the roles of force in physiological and disease processes, and is a major goal in the field of mechanobiology. However, existing biosensors for 3D tissue mechanics, primarily based on fluorescent emissions and deformable materials, are limited for in vivo measurement due to the limited light penetration and poor material stability inside intact, living organisms. While magneto-motive ultrasound (MMUS), which uses superparamagnetic nanoparticles as imaging contrast agents, has emerged as a promising modality for real-time in vivo imaging of tissue mechanics, it has poor sensitivity and spatiotemporal resolution. To overcome these limitations, we introduce magneto-gas vesicles (MGVs), a unique class of protein nanostructures based on gas vesicles and magnetic nanoparticles that produces differential ultrasound signals in response to varying mechanical properties of surrounding tissues. These hybrid protein nanostructures significantly improve signal strength and detection sensitivity. Furthermore, MGVs enable non-invasive, long-term, and quantitative measurement of mechanical properties within 3D tissues and organs in vivo. We demonstrated the performance of MGV-based mechano-sensors in vitro, in fibrosis models of organoids, and in vivo in mouse liver fibrosis models.

biochemistry↗

bioRxiv2020

Remote-controlled insect navigation using plasmonic nanotattoos

Developing insect cyborgs by integrating external components (optical, electrical or mechanical) with biological counterparts has a potential to offer elegant solutions for complex engineering problems.1 A key limiting step in the development of such biorobots arises at the nano-bio interface, i.e. between the organism and the nano implant that offers remote controllability.1,2 Often, invasive procedures are necessary that tend to severely compromise the navigation capabilities as well as the longevity of such biorobots. Therefore, we sought to develop a non-invasive solution using plasmonic nanostructures that can be photoexcited to generate heat with spatial and temporal control. We designed a nanotattoo using silk that can interface the plasmonic nanostructures with a biological tissue. Our results reveal that both structural and functional integrity of the biological tissues such as insect antenna, compound eyes and wings were preserved after the attachment of the nanotattoo. Finally, we demonstrate that insects with the plasmonic nanotattoos can be remote controlled using light and integrated with functional recognition elements to detect the chemical environment in the region of interest. In sum, we believe that the proposed technology will play a crucial role in the emerging fields of biorobotics and other nano-bio applications.

bioengineering↗