Cathelicidin (LL-37) and its correlation with pro-oxidant, antioxidant balance and disease activity in systemic lupus erythematosus: a cross-sectional human study.

Background Cathelicidin (LL-37), an endogenous antimicrobial peptide, has recently been involved in the pathogenesis of autoimmune diseases. To assess whether LL-37 reflects disease activity, we measured serum levels of it in systemic lupus erythematosus (SLE) patients with active and inactive disease compared to healthy controls. LL-37 was also compared between new and old cases. Moreover, the correlation of LL-37 and pro-oxidant, antioxidant balance (PAB) was measured. Methods The study population consisted of 50 SLE patients and 28 healthy controls. Of those, 39 patients had active and 11 patients had inactive disease. Serum levels of LL-37 were measured by ELISA and PAB values by a special method. Results There was no difference in levels of LL-37 between patients and healthy controls (50.9 ± 20.8 vs. 67.7 ± 43.3 ng/ml, P = 0.31). LL-37 did not correlate with SLEDAI and its items in total patients. LL-37 had a positive correlation with SLEDAI in active patients ( P = 0.01, r = 0.4). In active patients (78% of patients), multivariate regression analysis showed significant negative correlation between LL-37 and C3 ( P = 0.01, standardized beta -0.50). No difference was found in levels of PAB between patients and controls (90.4 ± 34.1 vs. 86.9 ± 25.6 HK, P = 0.4).There was no difference in the levels of PAB between patients with active and inactive disease (93.2 ± 34.1 vs. 80.2 ± 33.7 HK, P = 0.27). No correlation was found between levels of PAB and SLEDAI items and total score. However, a positive correlation between the levels of LL-37 and PAB in SLE patients was found ( r = 0.3, P < 0.01). Conclusion Based on this study, serum LL-37 and PAB did not increase in lupus compared with healthy individuals. LL-37 serum values rose in parallel with SLEDAI in active disease. Positive correlation between serum PAB and LL-37 could be a great achievement of this study that may suggest the role of antioxidants in controlling NETosis.

Prevalence of goiter among schoolchildren from Gorgan, Iran, a decade after national iodine supplementation: association with age, gender, and thyroperoxidase antibodies.

BACKGROUND: One decade after universal salt iodization in Iran, goiter prevalence, urinary iodine concentration (UIC) and thyroperoxidase antibody (TPOAb) values were assessed among schoolchildren in Gorgan, Iran. METHODS: From 2003-2004, 500 girls and 900 boys aged 7-11 yr were evaluated for goiter by palpation. UIC was measured in 183 randomly-selected goitrous children. Serum TSH, T4, and TPOAb were measured in 53 goitrous and 30 non-goitrous children with adequate UIC. RESULTS: Goiter was detected in 370 (26.4%) children. Goiter was present in 31% of girls and 17% of boys age 9 (p<0.012); 37% of girls and 20% of boys age 10 (p<0.003); and 52% of girls and 19% of boys age 11 (p<0.0001). Median (range) UIC for all goitrous children sampled was 190 (20-600) microg/l; 220 (30590) in boys and 170 (20-600) in girls (p=0.001). Eight point seven percent of goitrous children and 22% of goitrous girls aged 10-11 had UIC<100 microg/l, while 47% of the goitrous children had UIC> or =200 microg/ l. TPOAb was present in 52.8% of goitrous children and 10% of non-goitrous children (p=0.0001). TPOAb was present in 53.9% of 10-11 and 22.7% of 7-9 yr old goitrous and non-goitrous children (p=0.003) with adequate UIC. Median (range) TSH was 2.9 (0.3-10.9) mlU/I in TPO-positive and 1.8 (0.5-4.1) in TPO-negative children (p=0.001). CONCLUSIONS: Gorgan, Iran, is an iodine-sufficient area and almost half of schoolchildren have more than adequate UIC. TPOAb is associated with endemic goiter. Despite sufficient UIC overall, some school-aged girls remain at risk of iodine deficiency.