Expression wrinkles are some of the first signs of aging. They are mainly caused by the excessive stimulation of the muscle fibers in the face, which pulls the skin inwards and causes wrinkles to appear on the skin surface. Thus, by attenuating the muscle contraction, the appearance of these wrinkles can be minimized.
Muscles are contracted when they receive a neurotransmitter released from inside a vesicle of the motor neuron. This process is mediated by three specific proteins found in the motor neuron, the vesicle-associated membrane protein (VAMP), the membrane-associated protein (syntaxin) and synaptosomal associated protein 25 (SNAP-25). These proteins assemble to form a ternary structure known as the SNARE complex, which is like a cellular hook that captures the vesicles and fuses them with the membrane. Once the fusion of these vesicles occurs, acetylcholine (ACh) is released into the synapse between nerve and muscle cells. Then, ACh binds to specific receptors called acetylcholine receptors (AChR) located on the surface of muscle cells, finally triggering muscle contraction.
Acetyl Hexapeptide-8 is a mimic of the N-terminal end of SNAP-25 which competes with SNAP-25 for a position in the SNARE complex, thereby modulating its formation. If the SNARE complex is slightly destabilized, the vesicle cannot release neurotransmitters efficiently and therefore muscle contraction is attenuated, preventing the formation of lines and wrinkles.
It can be incorporated in cosmetic formulations such as emulsions, gels, essence, eye cream, etc., where removal of the deep lines or wrinkles in the forehead or around the eyes area is desired. |