Objective:To investigate the effect of angiotensin II (ang II), aldosterone (ald) and their receptor antagonists losartan (los) and spironolactone (spi) on the proliferation and collagen production of cardiac ifbroblasts (CFs) in rats.
Methods:CFs were isolated from neonatal SD rats by collagenase II method and puriifed with differential attachment and detachment method. The 3 or 4 passages of the CFs were divided into the following groups:angiotensin II, angiotensin II+aldosterone, aldosterone, angiotensin II+losartan, and aldosterone+spironolactone. The cell viability of the CFs was assessed by Cell Counting Kit-8 (CCK-8) after the drug administration. The mRNA and protein expression levels of COL1A1, COL3A1, MMP1 and TIMP1 were detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blot respectively.
Results:Ang II and Ald facilitated the proliferation rate of the CFs independently compared with that in the control group (38.5%vs 28.5%;P<0.05), and the proliferation rate in the ang II+ald group was higher than that in the ang II group and ald group alone (54.4%, P<0.05). Los and spi inhibited the effect induced by ang II and ald respectively (P<0.05). Compared with the control group, ang II and ald signiifcantly enhanced COL1A1, COL3A1 and MMP1 expression both at the mRNA and protein levels (P<0.05), but the TIMP1 expression was inhibited (P<0.05), which could be abolished by corresponding receptor antagonists los and spi (P<0.05).
Conclusion:Ang II and ald can promote the proliferation of CFs, and the COL1A1 and COL3A1 expression is enhanced both at mRNA and protein levels. Ang II and ald have synergistic effect when they are used together, while los and spi may restrain the effect. The mechanism is probably linked with the balance of MMPs/TIMPs.

Objective To investigate changes and the clinical significance of serum 25-Hydroxyvitamin D level in patients of Xinjiang Uygur and Han nationalities with mild cognitive impairment.Methods On the base of early stage of epidemiological survey of Xinjiang Uygur and Han population over 60 years old,adopting multi-stage stratified random cluster sampling method and referencing DSM-Ⅳ,206 cases of MCI patients (study group)were selected and 412 healthy elderly subjects (control) matching for age,nationality and gender were recruited for case-control study.The serum level of 25(OH) D was measured by enzyme-linked immunosorbent assay (ELISA).Results The serum level of 25(OH)D was significantly lower in MCI group of two nationalities (7.89±0.29 μg/L) than in normal control group [(8.65± 0.21) μg/ml,P＜0.05].The serum level of 25(OH)D was (8.41±0.34) μg/L in Han group,and (8.37±0.32)μg/L in Uygur group,with no significant difference (P＞0.05).The 25 (OH)D level was significantly lower in female[(8.23± 0.32) μg/L] than in male [(8.70±0.42) μg/L,P＜0.05].The serum level of 25(OH)D was lower in female MCI group [(7.56±0.34) μg/L] than in female control group [(8.41 ±0.31)μg/L],with significant difference (P＜0.05).While there was no significant difference between male MCI and male control group (P＞0.05).Multivariate Cox regression analysis showed that the risk factors of MCI might include low serum 25 (OH) D levels (OR =1.163,95 ％ CI:0.978-1.447),a decreased physical labor (OR=1.420,95％ CI:1.10-1.860),low education degree (OR =1.504,95％ CI:1.129-2.130),celibacy (OR=1.293,95％CI:0.845-1.440),hypertension (OR=1.954,95％CI:1.342-2.670),diabetes (OR =1.320,95％ CI:1.145-1.710),smoking history (OR =1.350,95％ CI:1.101-2.293),high BMI (OR=1.329,95％CI:1.068-1.781).Conclusions The serum 25(OH)D level is lower in MCI patients in Xinjiang Uygur and Han populations than in normal people,but there is no significant difference.The 25 (OH)D deficiency is associated with increased odds for cognitive impairment in the elderly Xinjiang population,which is more obvious in the female.The occurrence and development of MCI is affected by multiple risk factors.