Platelet-derived miR-142-3p induces apoptosis of endothelial cells in hypertension.

The dysfunction of endothelial cells (ECs) plays crucial roles in vascular remodeling during hypertension. Researches suggested that ECs are regulated by the circulating platelets in vivo, which may participate in abnormal EC apoptosis in hypertension. However the molecular mechanism in this process is still unclear. Here we focused on the microRNAs (miRs) in platelets, and detected the potential role and delivery mechanism of platelet-derived miRs in ECs. Using microarray, the differentially expressed profile of miRs between platelets and ECs was detected. The results revealed that compared with ECs, 67 miRs highly expressed in platelets including the most significant one- miR-142-3p. Since platelets are activated by thrombin in hypertension, we detected the miR-142-3p transferring mechanism of activated platelet, and proved that platelet-derived microparticles (PMPs), but not platelets directly, delivered miR-142-3p into ECs via cellular adherent. Furthermore, BCL2L1, an important molecule in cell apoptosis, was predicted to be a putative target of miR-142-3p by multiple algorithms. Dual luciferase reporter assays, as well as miR-142-3p mimics treatment were used to confirm the interplay between miR-142-3p and BCL2L1. Meanwhile, using in vivo hypertensive rat model, our results showed that the expression of platelet-derived miR-142-3p and the apoptosis were both significantly increased in ECs during hypertension. The present results suggested that platelet-derived miR-142-3p is delivered into ECs via PMPs, and may modulate the expression of target molecule- BCL2L1, which may subsequently display a negative function by modulating EC apoptosis in hypertension.

Prevalence of primary Sjögren's syndrome in China.

OBJECTIVE: To determine the prevalence rate of primary Sjögren's syndrome (SS) in a community population of 2066 adults in a Beijing suburban village, and 100 inpatients, who were not necessarily admitted for rheumatic diseases. METHODS: Questionnaire and serological studies of antinuclear antibodies, rheumatoid factor, and anti-SSA, anti-SSB antibodies were done. Possible positive subjects were given eye and oral examinations for objective evidence of xerostomia and keratoconjunctivitis sicca. RESULTS: According to the Copenhagen criteria, the prevalence rate of primary Sjögren's syndrome in China was 0.77%, and it was 0.33% by modified San Diego criteria. In 100 inpatients, we found 4 cases of primary Sjögren's syndrome by Copenhagen criteria, and one case by modified San Diego criteria. CONCLUSION: Primary Sjögren's syndrome is not a rare disease in China, but most cases are overlooked or misdiagnosed.

[Effects of tripchlorolide (T4) of Tripterygium wilfordii hook on the production of prostaglandin E2 by synovial cells of rheumatoid arthritis].

The effects of tripchlorolide, an active ingredient (T4) of Tripterygium wilfordii Hook on the production of prostaglandin E2(PGE2) by synovial cells of rheumatoid arthritis (RA) patients were investigated. Six cases of definite RA (female 5, male 1, mean age 45 with an average course of disease of 9 years) were selected. Surgically obtained synovium specimen were dissociated into digested synovial single cells (DSSC). The cells were incubated with various concentrations of T4 for 48 hours. Using radioimmunoassay T4 was found to significantly inhibit the production of PGE2 (control 6.10 +/- 2.30 vs T4 treated 0.58 +/- 0.47 x 10(-5) mol.L-1) by short-term cultured DSSC of RA patients. The results of this study suggests that T4 may be useful in the forthcoming treatment of RA due to its inhibition of production of PGE2 by synovial cells.

[Epidemiological studies on primary Sjogren's syndrome].

2,066 adult people of a Beijing suburb village were surveyed for primary Sjogren's syndrome, using questionnaire and serological tests in each case as the primary screening tool. 16 cases were discovered by Copenhagen criteria indicating a prevalence rate of 0.77% and 7 cases with a prevalence rate of 0.33% by Fox criteria. Similar study was done in 100 non-connective tissue diseases in-patients. 4 cases were discovered by Copenhagen criteria and one case by Fox criteria. In 126 definite cases of primary Sjogren's syndrome, the longest time interval between first onset of symptoms and firm establishment of diagnosis was 20 years with an average of 7.8 years indicating most cases were wrongly diagnosed or highly neglected.