Aging shifts serotonin signaling patterns in spinal neurons, increasing sensitivity to mechanical itch through elevated 5-HT7 receptor expression. Blocking this receptor pathway reduces age-related itch hypersensitivity, identifying a specific neurochemical mechanism underlying chronic pruritus in older adults.
Key Points
- Aged mice show enhanced mechanical itch without spontaneous scratching changes
- Elevated urinary serotonin and 5-HT7 receptor upregulation in spinal neurons
- 5-HT7 receptor blockade attenuates mechanical itch behavior in aging
Longevity Analysis
Age-related itch represents a measurable shift in how the nervous system processes sensory input—a signal decoding problem that manifests as heightened sensitivity to mechanical stimuli. The underlying mechanism involves altered serotonin homeostasis and receptor expression patterns that can be pharmacologically modulated, suggesting that age-related changes in neurotransmitter signaling are not fixed but addressable. Understanding these neurochemical remodeling patterns offers a pathway to distinguish between normal aging-related changes and pathological hypersensitivity, improving quality of life and informing therapeutic strategies that work with the body's communication systems rather than against them.
Original published by Wiley Aging Cell, by Qiaofeng Zhao, Alberto Leguina‐Ruzzi, Mitsutoshi Tominaga, Yayoi Kamata, Atsuko Kamo, Huiying Wan, Bin Yin, Yuping Ran, Kenji Takamori .