Submandibular gland autotransplantation is effective for treating severe dry eye syndrome. However, more than 40% of patients show epiphora within 3 to 6 months after treatment. The mechanism underlying the hypersecretion in epiphora remains to be elucidated for developing novel interventions. Since salivary gland secretion is dependent on a variety of proteins, we analyzed the changes in protein expression in transplanted glands of epiphora patients with 2-D gel electrophoresis and electrospray ionization quadrupole/time-of-flight mass spectrometry and evaluated their possible roles in epiphora. There were 23 proteins showed altered expression in the glands of epiphora patients, 15 being up-expressed and 8 down-expressed. The expression of secretory proteins was decreased in these glands, including alpha-amylase, cystatin S, SA, and SN. In contrast, cytoskeletal proteins were all upregulated, including actin and vimentin. Immunofluorescence revealed the intensity ratio of F-actin in apical and lateral cytoplasm to total F-actin in acini was decreased in the glands of epiphora patients. Carbachol stimulation induced a similar redistribution of F-actin in the control glands. Phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) was increased in both carbachol-stimulated and epiphora glands. Preincubation of submandibular glands with ERK1/2 inhibitors PD98059 or U0126 inhibited carbachol-induced F-actin redistribution. These results indicated that differentially expressed proteins participated in hypersecretion of transplanted submandibular glands, and the redistribution of F-actin might be involved in this hypersecretion in an ERK1/2-dependent manner
J Proteome Res. 2011 Mar 8. [Epub ahead of print]
Ding C, Zhang Y, Peng X, Wang Y, Zhang L, Cong X, Ding QW, Xiang RL, Wu LL, Yu GY.