Bone, from Chinese work

A Shanghai group showed that kisspeptin-10 binding GPR54 on osteoclasts, the cells that dissolve bone, switches on a phosphatase called Dusp18 which dephosphorylates Src and calms the cell down. Mice lacking Kiss1, Gpr54 or Dusp18 all showed over-active osteoclasts and lost bone, and giving kisspeptin-10 prevented that loss. Over-active bone dissolving is the mechanism of age-related bone thinning. This is a direct action on bone, separate from the hormone route everything else here runs through.