Silk Hydrogel Substrate Stress Relaxation Primes Mesenchymal Stem Cell Behavior in 2D.
Suttinee PhuagkhaopongLuís MendesKatrin MüllerManja WobusMartin BornhäuserHilary V O CarswellIola F DuarteF Philipp SeibPublished in: ACS applied materials & interfaces (2021)
Tissue-mimetic silk hydrogels are being explored for diverse healthcare applications, including stem cell delivery. However, the impact of stress relaxation of silk hydrogels on human mesenchymal stem cell (MSC) biology is poorly defined. The aim of this study was to fabricate silk hydrogels with tuned mechanical properties that allowed the regulation of MSC biology in two dimensions. The silk content and stiffness of both elastic and viscoelastic silk hydrogels were kept constant to permit direct comparisons. Gene expression of IL-1β, IL-6, LIF, BMP-6, BMP-7, and protein tyrosine phosphatase receptor type C were substantially higher in MSCs cultured on elastic hydrogels than those on viscoelastic hydrogels, whereas this pattern was reversed for insulin, HNF-1A, and SOX-2. Protein expression was also mechanosensitive and the elastic cultures showed strong activation of IL-1β signaling in response to hydrogel mechanics. An elastic substrate also induced higher consumption of glucose and aspartate, coupled with a higher secretion of lactate, than was observed in MSCs grown on viscoelastic substrate. However, both silk hydrogels changed the magnitude of consumption of glucose, pyruvate, glutamine, and aspartate, and also metabolite secretion, resulting in an overall lower metabolic activity than that found in control cells. Together, these findings describe how stress relaxation impacts the overall biology of MSCs cultured on silk hydrogels.
Keyphrases
- tissue engineering
- wound healing
- mesenchymal stem cells
- drug delivery
- hyaluronic acid
- stem cells
- umbilical cord
- gene expression
- healthcare
- endothelial cells
- bone marrow
- type diabetes
- extracellular matrix
- drug release
- atomic force microscopy
- single molecule
- metabolic syndrome
- induced apoptosis
- amino acid
- blood pressure
- blood glucose
- mass spectrometry
- inflammatory response
- weight loss
- toll like receptor
- cell therapy
- oxidative stress
- protein kinase
- skeletal muscle
- drug induced
- nuclear factor