Flavonol

Flavonols are a prominent subclass of flavonoids, which are polyphenolic secondary metabolites synthesized by plants and found abundantly in human diets, including fruits like apples and berries, vegetables like onions and kale, and beverages like tea and wine [3, 8]. Structurally, they are defined by a 3-hydroxyflavone backbone (3-hydroxy-2-phenylchromen-4-one) [13, 14]. Flavonols are not considered therapeutic targets themselves (such as receptors or enzymes) but are bioactive compounds that interact with and modulate a wide array of biological targets, including protein kinases like PI3K and DYRK1A, inflammatory enzymes like cyclooxygenase (COX) and lipoxygenase (LOX), and transcription factors such as NF-κB [3, 7, 18]. Their primary biological roles involve acting as antioxidants by scavenging free radicals and chelating metal ions, thereby protecting cells from oxidative stress-related damage [13, 15, 17]. Clinically, flavonols are investigated for their potential to reduce the risk and progression of various chronic conditions, including cancer, cardiovascular disease, diabetes, and neurodegenerative disorders, through their anti-inflammatory and anti-proliferative actions [1, 9, 10]. Despite their diverse pharmacological potential, their therapeutic application is often limited by poor oral bioavailability and potential drug-drug interactions resulting from the inhibition of cytochrome P450 enzymes [12, 14].

Other names

Flavonols3-hydroxyflavones3-hydroxy-2-phenylchromen-4-one derivativesDietary flavonols

Flavonols act as bioactive ligands and multi-target enzyme inhibitors; they modulate cellular signaling by targeting kinases like PI3K and DYRK1A, inhibit pro-inflammatory enzymes such as COX-2 and LOX, and provide direct antioxidant effects by scavenging reactive oxygen species and chelating transition metals.