Activation of the Melanocortin-4 receptor signaling by α-MSH stimulates nerve-dependent mouse digit regeneration

The melanocortin 4 receptor (MC4R) is known for its role in energy balance, but recent studies suggest it has broader functions in the body, including tissue regeneration. This study explores the role of MC4R in mouse digit regeneration. The researchers used mice with a fluorescent marker for MC4R to observe where and when the receptor is active during limb and digit development. They also tested whether activating MC4R signaling with a drug called α-MSH could improve digit regeneration, even in situations where regeneration is usually impaired. The study found that MC4R is expressed in limb nerves and muscles during development, and in the nail matrix in adult digits. Activating MC4R signaling with α-MSH enhanced digit regeneration, even after nerve damage or in parts of the digit that don't normally regenerate well. This suggests MC4R has a neurotrophic role in digit regeneration.

• 1
  Mc4r expression in the mouse limb and digit is closely related to nerve tissues.
• 2
  α-MSH administration rescues regeneration of the denervated digits.
• 3
  α-MSH activation of MC4R signaling stimulates digit regeneration in denervated hindlimbs, and induces proximal digit regeneration.