Officials demoted me intentionally and now harassing what can be done

Dear Sir I am working in a private university. I was demoted by the officials of the university without any reason and because of my demotion my allowance was also reduced by 5000/-. My seniors harassed me and even after complaining to HR no action taken against them. I am physically handicapped person having 50% disability in the left leg. I had to take the amount of classes which are impossible to handle for me. I also approached the HR to reduce the load but they never reacted to it.I am in lot of physical stress because of leg problem. What options do I have.