Run the wires through conduit.

I used to have that problem with my cat and ferrets all you have to do is buy something called BitterApple at the pet store it comes in a cream and a spray its made for animals with chewing problems they dont like the taste so they learn not to mess with it. the cream would work better sence it lasts longer but if you cant find the cream the spray will work fine you will just have to apply it more often until your kitty learns if its the spray after you spray it on the cords make sure you rub the cord lenght with your fingers so that way you know you got every inch of it