Catecholoestrogens: possible role in systemic lupus erythematosus.

It is well established that risk of developing SLE is higher among women compared with men but only very little is understood about the underlying mechanisms. Oestrogen and their catechol metabolites seem to play an important role in SLE but the exact patho-aetiology remains elusive. The evidences concerning the possibility of catecholoestrogens (CEs) in the development of SLE are very limited and preliminary. The possible mechanism involves quinone-semiquinone redox cycling of CEs to generate the free radical that can cause DNA damage. This would probably alter its immunogenicity leading to the induction and elevated levels of SLE autoantibodies cross-reacting with native DNA. The data demonstrate the possible role of CE in presenting unique neo-epitopes that might form one of the factors in induction of SLE autoantibodies. However, the role of oestrogen in immune modulation cannot be rule out as a mediator of various immune-related diseases.