Chinnathambi, S. | bioRxiv Science

bioRxiv2018

Molecular Complexes for Effective Inhibition of Tau Aggregation

Tau is an axonal protein known to form abnormal aggregates and is the biomarker of Alzheimers disease. Metal-based therapeutics for inhibition of Tau aggregation is limited and rarely reported in the contemporary science. Here, the first example is reported of a rationally designed molecular cobalt(II)-complexes for effective inhibition of Tau and disaggregation of preformed Tau fibrils. The mechanistic studies revealed that the prevention of Tau aggregation by CBMCs is concentration-dependent and Tau seldom exhibits conformational changes. Interestingly, CBMCs play a dual role by causing disassembly of preformed aggregates as well as complete Tau inhibition. We believe that this unprecedented finding by the newly developed molecular complexes has a potential to lead to developing innovative metal-based therapeutics for Alzheimers disease.

neuroscience↗

bioRxiv2018

Substrate deformations induce directed keratinocyte migration

Cell migration is an essential part of many (patho)physiological processes in the body, including keratinocyte re-epithelialization of healing wounds. Recent interest in the mechanobiology of tissues suggests that physical forces and mechanical cues from the wound bed (in addition to biochemical signals) may also play an important role in the healing process. Previously, we explored this possibility and found that polyacrylamide (PA) gel stiffness affected primary human keratinocyte behavior and that mechanical deformations in soft (~1.2 kPA) PA gels produced by neighboring cells appeared to influence the process of de novo epithelial sheet formation. In order to clearly demonstrate that keratinocytes do respond to such deformations, we conducted a series of experiments where we observed the response of single keratinocytes to a prescribed local substrate deformation that mimicked a neighboring cell or evolving multicellular aggregate via a servo-controlled microneedle. We also examined the effect of adding either Y27632, a rho kinase inhibitor, or blebbistatin, a non-muscle myosin II inhibitor, on the response of the cells to PA gel deformations. The results of this study indicate that keratinocytes do sense and respond to mechanical signals comparable to those that originate from substrate displacements imposed by neighboring cells, a finding that could have important implications for the process of keratinocyte re-epithelialization that takes place during normal and pathologic wound healing. Furthermore, the Rho/ROCK pathway and the engagement of NM II are both essential to the observed process of substrate deformation-directed keratinocyte migration.

biophysics↗