TNF-α (Tumour Necrosis Factor alpha)

TNF-α (tumor necrosis factor alpha) is a powerful pro-inflammatory signal (a cytokine). It is made mostly by immune cells called macrophages and monocytes, when they sense infection or injury. It signals through two receptors. TNFR1 is everywhere and drives inflammation and cell death. TNFR2 sits mainly on immune and blood-vessel cells, and leans toward cell survival and immune regulation. Inside cells, TNF-α switches on the NF-κB and MAPK pathways. Those crank up sticky adhesion molecules, more cytokines, and inflammation proteins. When TNF-α stays high in your body for the long haul, it is a core part of 'inflammaging'. It feeds insulin resistance, muscle wasting (cachexia and sarcopenia), and brain inflammation. Anti-TNF drugs (etanercept, infliximab, adalimumab) are well-established for rheumatoid arthritis and inflammatory bowel disease. Their possible role in age-related inflammation is an active area of study.

Last reviewed: June 22, 2026

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