Blocking the action of TNF-alpha may slow the progression of Parkinson’s disease.
Parkinson’s disease is a progressive neurodegenerative disorder that affects the central nervous system. It is caused by the destruction of nerve cells in the part of the brain called the substantia nigra. Approximately 1 percent of all adults over the age of 60 years lives with Parkinson’s disease. Findings from a 2006 study suggest that blocking the action of tumor necrosis factor-alpha slows the progression of Parkinson’s disease.
Tumor necrosis factor-alpha (TNF-alpha) is a pro-inflammatory cytokine that is produced by a wide range of cells, including macrophages, lymphocytes, glial cells, and others. TNF-alpha signaling inhibits tumorigenesis, prevents viral replication, and induces fever and apoptosis. Dysregulation of the TNF-alpha signaling pathway has been implicated in a variety of disorders, including cancer, autoimmune diseases, Alzheimer’s disease, and depression.
The investigators injected the brains of mice with either lipopolysaccharide (LPS, an endotoxin that promotes acute inflammation) or 6-hydroxydopamine (a neurotoxin) and assessed the animals' brains for evidence of substantia nigra cell death. They injected a compound called XENP345 (a TNF-alpha inhibitor) into the brains of some of the mice. They also applied LPS and 6-hydroxydopamine to cultured neuronal cells and assessed the effects of XENP345 on cell death.
They found that both LPS and 6-hydroxydopamine caused marked cell death in the substantia nigra region of the animals' brains. They also found that inhibiting TNF-alpha via XENP345 in the brains and in cultured cells reduced cell death by roughly half.
These findings suggest that inhibiting the activity of the pro-inflammatory cytokine TNF-alpha reduces cell death in an animal model of Parkinson’s disease. Robust evidence indicates that exercise, which also reduces inflammation, slows the progression of Parkinson’s disease. Learn more about the effects of exercise on Parkinson’s disease in this episode featuring Dr. Giselle Petzinger.