Oxidative stress in the levator aponeurosis in Asian involutional blepharoptosis

To analyze the histopathology and expression of 8-hydroxydeoxyguanosine (OHdG), a marker of oxidative stress, in the levator aponeurosis tissues of involutional aponeurotic and congenital blepharoptosis patients, and adult subjects with no history of blepharoptosis.

Fourteen and 4 levator aponeurosis tissues obtained from Asian patients with involutional and congenital blepharoptosis and 3 normal adult tissues were examined. All tissues were fixed in 4% paraformaldehyde, embedded in paraffin, and then submitted for hematoxylin and eosin staining and immunohistochemistry with anti-8-OHdG antibody.

The levator aponeurosis tissues contained spindle smooth muscle fibers and striated muscles. Nuclear immunoreactivity for 8-OHdG was noted in striated and smooth muscle cells in all the tissues. The 8-OHdG-positive rate was significantly lower in congenital blepharoptosis than involutional blepharoptosis (p < 0.05). Moreover, the number of 8-OHdG-positive striated muscle cells was significantly higher in the involutional blepharoptosis than normal tissues (p < 0.05). In contrast, there was a rare positive 8-OHdG-immunoreactivity of smooth muscle cells in the aponeurotic tissues of the involutional blepharoptosis patients.

Levator aponeurosis in involutional aponeurotic blepharoptosis tissues showed oxidative stress in the muscle, indicating that oxidative stress plays a potential role in the pathologic study of the disease.