Antimicrobial peptides (AMPs) have caught the attention of researchers over the last couple of years due to their unique membrane lytic mechanism for combating antibiotic resistance, which differs from the molecular targets of traditional antibiotics. Although natural AMPs exhibit potential antimicrobial activity against a wide range of microorganisms, some drawbacks, such as toxicity, low antibacterial activity, and high production costs limit their clinical application. To enhance the antimicrobial activity of a series of HSP peptides derived from the natural peptide HSP-1, this study optimized them using a variety of strategies, including net charge, hydrophobic moment, hydrophobicity, and helicity. Optimizing the antimicrobial action of HSP peptides depended mostly on net charge, hydrophobic moment, and hydrophobicity rather than helicity. HSP-M4 may be designed to combat microbial infections because the antimicrobial activity and cytotoxicity assays showed that they exhibited low cytotoxicity and prominent antimicrobial activity, respectively.

The imbalance of the renin–angiotensin system (RAS), characterized by the overactivation of the pro-tumor ACE/AngII/AT1R axis, is closely linked to tumor growth, angiogenesis, metastasis, and poor prognosis. Natural polyphenols, such as EGCG and resveratrol, exert anti-cancer effects by dual-regulating RAS: they inhibit the pro-tumor axis by blocking renin, ACE activity, and AT1R expression, while simultaneously activating the protective ACE2/Ang(1-7)/MasR axis. Furthermore, polyphenols and their autoxidation products (e.g., EAOP) modify thiol-containing transmembrane proteins (such as ADAM17 and integrins) and interact with RAS components, further disrupting oncogenic pathways (including MAPK and PI3K/Akt/mTOR) to induce apoptosis, suppress invasion, and reduce oxidative stress. Notably, EAOP exhibits stronger RAS-modulating efficacy than its parent polyphenols. However, challenges such as low bioavailability, insufficient targeting, and limited clinical evidence impede their application. This review provides a comprehensive overview of the anti-cancer mechanisms of polyphenols through RAS regulation, discusses the associated challenges, and proposes potential solutions (including nanodelivery and structural modification) and strategies to advance natural product-based adjuvant treatments.