Quercetin

Quercetin's senolytic mechanism involves inhibition of multiple anti-apoptotic 'SCAPs' (senescent cell anti-apoptotic pathway) proteins including BCL-XL, BCL-W, and PI3K/AKT signaling. Senescent cells upregulate these survival pathways to resist apoptosis; quercetin selectively destabilizes them, reactivating apoptosis preferentially in senescent vs healthy cells. The Kirkland lab D+Q protocol pairs quercetin (which targets BCL-XL/BCL-W and PI3K) with dasatinib (which targets ephrin-dependent senescent cell types) for broader senolytic coverage.,Beyond senolysis, quercetin acts as an AMPK activator (similar to other polyphenols like resveratrol), inducing mitochondrial biogenesis via PGC-1alpha and supporting cellular energy homeostasis. It inhibits NF-kB inflammatory signaling, reducing TNF-alpha, IL-6, and other pro-inflammatory cytokines. Mast cell stabilization occurs via inhibition of calcium influx and histamine granule release - quercetin is mechanistically similar to cromolyn sodium (a prescription mast cell stabilizer).,As a zinc ionophore, quercetin transports zinc across cell membranes into cells where intracellular zinc inhibits viral RNA polymerases (including SARS-CoV-2 RdRp). This mechanism underlies the immune/antiviral interest. Quercetin also has direct antioxidant capacity via its catechol structure, donating electrons to neutralize free radicals; the resulting quercetin radical is itself relatively stable. Cardiovascular effects involve eNOS activation (improving endothelial NO production), modest BP reduction in hypertensive subjects, and platelet aggregation modulation.

Quercetin's senolytic mechanism involves inhibition of multiple anti-apoptotic 'SCAPs' (senescent cell anti-apoptotic pathway) proteins including BCL-XL, BCL-W, and PI3K/AKT signaling. Senescent cells upregulate these survival pathways to resist apoptosis; quercetin selectively destabilizes them, reactivating apoptosis preferentially in senescent vs healthy cells. The Kirkland lab D+Q protocol pairs quercetin (which targets BCL-XL/BCL-W and PI3K) with dasatinib (which targets ephrin-dependent senescent cell types) for broader senolytic coverage.,Beyond senolysis, quercetin acts as an AMPK activator (similar to other polyphenols like resveratrol), inducing mitochondrial biogenesis via PGC-1alpha and supporting cellular energy homeostasis. It inhibits NF-kB inflammatory signaling, reducing TNF-alpha, IL-6, and other pro-inflammatory cytokines. Mast cell stabilization occurs via inhibition of calcium influx and histamine granule release - quercetin is mechanistically similar to cromolyn sodium (a prescription mast cell stabilizer).,As a zinc ionophore, quercetin transports zinc across cell membranes into cells where intracellular zinc inhibits viral RNA polymerases (including SARS-CoV-2 RdRp). This mechanism underlies the immune/antiviral interest. Quercetin also has direct antioxidant capacity via its catechol structure, donating electrons to neutralize free radicals; the resulting quercetin radical is itself relatively stable. Cardiovascular effects involve eNOS activation (improving endothelial NO production), modest BP reduction in hypertensive subjects, and platelet aggregation modulation.

What's safe to combine, and what belongs in a separate pin.

Storage. Store at room temperature (20-25C) in a cool, dry, dark place. Light and moisture-sensitive - keep in opaque containers. Capsules shelf-stable for 24+ months. Powder may oxidize and darken with prolonged exposure to air.

Classified as a dietary supplement in the US (no FDA pre-approval). Available widely over the counter. EU permits quercetin as a food supplement. Generally Recognized as Safe at typical supplement doses. Dasatinib (the D+Q partner drug) is FDA-approved for chronic myeloid leukemia and ALL - prescription only.