Cell-Penetrating Peptide-Mediated Modulation of Endoplasmic Reticulum Stress: A Bioengineered and Translational...

Endoplasmic reticulum (ER) stress is central to the onset and progression of metabolic and inflammatory disorders, such as insulin resistance, hepatic steatosis, and cardiovascular dysfunction. The unfolded protein response, triggered by ER stress, induces maladaptive pathways through PERK, IRE1, and ATF6, leading to inflammation, apoptosis, and cellular dysfunction. Targeted ER stress modulation is an attractive therapeutic approach, and recent developments in bioengineering have enabled precise delivery of modulatory agents using cell-penetrating peptides and adipose-derived stem cells. On the one hand, cell-penetrating peptides (CPPs) enable intracellular delivery of therapeutic cargoes such as siRNA, peptides, or small-molecule targeting key ER stress mediators, including CHOP, GRP78, IRE1, and NF-κB. CPP-mediated delivery systems restore ER homeostasis, reduce inflammatory signaling, and improve cellular survival in hepatocytes, pancreatic β-cells, and cardiomyocytes. Simultaneously, adipose tissue-derived stem cells (ADSCs), which are derived from lipo-aspirated fat tissue, induce paracrine effects through the secretion of anti-inflammatory cytokines (i.e., IL-10), growth factors (i.e., VEGF, HGF, TGF-β), and antioxidants that regulate ER stress responses. ADSCs also have adipogenic and endothelial differentiation, playing roles in repairing tissue and metabolic homeostasis. Downregulation of ER stress markers and mitigation of oxidative stress increase their therapeutic efficacy for metabolic disorders. Collectively, this bioengineered synergy of CPPs and ADSCs represents a multifunctional therapeutic platform to target ER stress and its downstream effects. This synergistic approach has translational potential for precision medicine in metabolic pathophysiology, advancing from laboratory innovations to clinical applications.