The cardiac nanoenvironment: form and function at the nanoscale

Abstract

Mechanical forces in the cardiovascular system occur over a wide range of length scales. At the whole organ level, large scale forces drive the beating heart as a synergistic unit. On the microscale, individual cells and their surrounding extracellular matrix (ECM) exhibit dynamic reciprocity, with mechanical feedback moving bidirectionally. Finally, in the nanometer regime, molecular features of cells and the ECM show remarkable sensitivity to mechanical cues. While small, these nanoscale properties are in many cases directly responsible for the mechanosensitive signaling processes that elicit cellular outcomes. Given the inherent challenges in observing, quantifying, and reconstituting this nanoscale environment, it is not surprising that this landscape has been understudied compared to larger length scales. Here, we aim to shine light upon the cardiac nanoenvironment, which plays a crucial role in maintaining physiological homeostasis while also underlying pathological processes. Thus, we will highlight strategies aimed at (1) elucidating the nanoscale components of the cardiac matrix, and (2) designing new materials and biosystems capable of mimicking these features in vitro.

Improving rodents and humans cardiac cell maturity in vitro through polycaprolactone and polyurethane nanofibers

“…Such differences were observed in the case of the size of nanofibers. The structure of the ECM in the human cardiac tissue is built by fibers whose diameter is up to 300 nm [48,49], and the most common range of diameter of nanofibers used in TE for cardiac cells is 200−700 nm [50,51]. For comparison, the PCL and PU nanofibers were produced in two diameters similar to the diameter of fibers building the ECM heart in vivo.…”

From Soft to Hard Biomimetic Materials: Tuning Micro/Nano-Architecture of Scaffolds for Tissue Regeneration

“…Collagen is the most abundant protein in the heart and confers strength and structural integrity. Collagen I forms rod-like fibrils with a diameter of ~300 nm, while collagen III forms smaller fibrils with a diameter of ~100 nm [ 86 ]. Elastin forms unit fibrils of ~0.2 µm thickness that confer elasticity [ 87 ].…”

Biophysical Reviews— 2021, the year that was

“…Among the many excellent contributions to this issue, I highlight the commentary by Prof. Mike Sheetz which provides an overview of the mechanobiology viewpoint of heart muscle contraction and regulation (Sheetz 2021 ). Three other scientific content articles of note are those contributed by a group from Australia examining physical modeling studies of the heart (Nguyen et al 2021 ); a group from the USA reviewing computational models of the beating heart (Sharifi et al 2020 ), and finally, a group from Singapore examining methods for measuring and mimicking micro to nanoscale features of the cardiac environment (Singh and Young 2021 ).…”