Effect of Main Versus Ancillary Ligand Substitution on the Photophysical Properties of a Series of Ir(III) Complexes: A Detailed Theoretical Investigation

Rationally Designed Ir(III) Complex with an Exceptionally Strong Binding to Human Serum Albumin for Targeted Photodynamic Therapy

The application of iridium(III) complexes in photodynamic therapy (PDT) is often limited by their poor selectivity for cancerous cells, necessitating high drug doses that increase the risk of side effects. The development of efficient drug delivery systems such as albumin conjugation is therefore crucial to enhance the tumor-targeted delivery of photosensitizers. To date, the vast majority of metal complexes exhibit weak to moderate binding with human serum albumin, limiting the feasibility of this approach. To overcome this limitation, the rational design through molecular docking and density functional theory calculations of a novel Ir(III) complex as a strong albumin-binding photosensitizer is described. The herein reported compound has the highest albumin binding constant ever reported for an iridium complex, and it showed to photocatalytically produce reactive oxygen species upon blue light irradiation. The presented compound as well as structural derivatives could have high potential in tumor-targeted photodynamic therapy.

Regulation of arachidonic acid oxidation and metabolism by lipid electrophiles

Arachidonic acid (AA) is a precursor of enzymatic and non-enzymatic oxidized products such as prostaglandins, thromboxanes, leukotrienes, lipoxins, and isoprostanes. These products may exert signaling or damaging roles during physiological and pathological conditions, some of them being markers of oxidative stress linked to inflammation. Recent data support the concept that cyclooxygenases (COX), lipoxygenases (LOX), and cytochrome P450 (CYP450) followed by cytosolic and microsomal dehydrogenases can convert AA to lipid-derived electrophiles (LDE). Lipid-derived electrophiles are fatty acid derivatives bearing an electron-withdrawing group that can react with nucleophiles at proteins, DNA, and small antioxidant molecules exerting potent signaling properties. This review aims to describe the formation, sources, and electrophilic anti-inflammatory actions of key mammalian LDE.