You can achieve this through multiple methods, I'm almost certain there is no available support for such feature.
However, in movements, you can create scripts executed when a player equips or deequips items (onEquip, onDeEquip) where you can assign a status condition (ATTRIBUTES) which in it's turn gives higher maximum health / mana, check the global.lua file for the specific condition constants.
Or you can implement this feature in the source, by typing in a value in the items.xml file.
Ignazio