Rapamycin Treatment Attenuates Angiotensin Ⅱ-induced Abdominal Aortic Aneurysm Formation via VSMC Phenotypic Modulation and Down-regulation of ERK1/2 Activity

The aim of the present study is to address the effect of rapamycin on abdominal aortic aneurysm（AAA） and the potential mechanisms. A clinically relevant AAA model was induced in apolipoprotein E-deficient（ApoE-/-） mice, in which miniosmotic pump was implanted subcutaneously to deliver angiotensin Ⅱ（Ang Ⅱ） for 14 days. Male ApoE-/-mice were randomly divided into 3 groups： saline infusion, Ang Ⅱ infusion, and Ang Ⅱ infusion plus intraperitoneal injection of rapamycin. The diameter of the supra-renal abdominal aorta was measured by ultrasonography at the end of the infusion. Then aortic tissue was excised and examined by Western blotting and histoimmunochemistry. Ang Ⅱ with or without rapamycin treatment was applied to the cultured vascular smooth muscle cells（VSMCs） in vitro. The results revealed that rapamycin treatment significantly attenuated the incidence of Ang Ⅱinduced-AAA in ApoE-/-mice. Histologic analysis showed that rapamycin treatment decreased disarray of elastin fibers and VSMCs hyperplasia in the medial layer. Immunochemistry staining and Western blotting documented the increased phospho-ERKl/2 and ERK1/2 expression in aortic walls in Ang Ⅱ induced-AAA,as well as in human lesions. Whereas in the rapamycintreated group, decreased phospho-ERK1/2 expression level was detected. Moreover, rapamycin reversed Ang Ⅱ-induced VSMCs phenotypic change both in vivo and in vitro. Based on those results, we confirmed that rapamycin therapy suppressed Ang Ⅱ-induced AAA formation in mice, partially via VSMCs phenotypic modulation and down-regulation of ERK1/2 activity.

Phenotypic Modulation of Mesangial Cells in Diabetic Rats and Effect of Tujian Mixture (菟箭合剂) on It

Objective: To explore whether there is phenotypic modulation of mesangial cells in streptozotocin (STZ) induced diabetic rats and study the effect of Tujian Mixture (TJM) on it. Methods: SD rats were divided into the normal control group , the unilateral nephrectomized control group , the STZ induced diabetes mellitus with unilateral nephrectomy model group , the Valsartan treated group (VT group, n=8) and the TJM treated group , rats in the latter two groups were modeled as in the DM group and treated with Valsartan (20 mg/kg·d) and TJM (20g/kg·d) respectively for 12 weeks. The expression of α-smooth muscle actin (α-SMA) and transforming growth factor-β 1 (TGF-β 1) in rats’ glomeruli were observed by immunohistochemistry assay, and the ratio of α-SMA and TGF-β 1 positive area/total glomerule tuft area (SMA/GT and TGF/GT) were analyzed using computer-assisted image analysis software. Results: In the NC and the QC groups, only trace of α-SMA positive staining was found. But there was prominant α-SMA positive staining in glomeruli of the DM group, with SMA/GT and TGF/GT increased significantly , and marked increase of 24 hrs proteinuria excretion ( P<0 01). As compared with the DM group, the three indexes were all significantly lower in the VT and ZY groups , and the lowering of proteinuria was more significant in the ZY group than that in the VT group (P<0 01). Conclusion: The expression of α-SMA in glomeruli in STZ induced diabetic rats with unilateral nephrectomy is pronounced, indicating that phenotypic modulation of mesangial cells involvement in the pathogenesis of diabetic nephropathy. TJM and Valsartan can reduce 24 hrs proteinuria excretion, inhibit the phenotypic modulation of mesangial cells and the expression of TGF-β 1 in glomeruli of diabetic rats, and the effect of TJM is more potent than that of Valsartan in lowering urinary protein excretion..

Effects of tetrandrine on phenotypic modulation of vascular smooth muscle cells and expression of p38 MAPK as well as MKP-1 after intimal injury of rabbit carotid arteries

Objective： To study the effects of tetrandrine （Tet） on phenotypic modulation of vascular smooth muscle cells （VSMCs） and expression of p38 mitogen-activated protein kinase （p38MAPK） as well as mitogen-activated protein kinase phosphatase-1 （MKP-1） after vascular intimal injury. Methods： HE staining was used to analyze vascular morphology of sham-injured group, injured group and Tet-treated group at day 28. lmmunohistochemistry, Western blot and RT-PCR were respectively used to detect the expression change of smooth muscle a-actin （SMa-actin）, proliferation cell nuclear antigen （PCNA）, p38MAPK and MKP-1 of injured group and Tet group at days 7, 14 and 28 after balloon injury. Results： ① All layers of vascular wall in sham-injured group were intact at day 28. The neointimal area was significantly increased and the lumen area notably decreased in injured group at day 28. The neointimal proliferation in Tet treated group was less than that in injured group, and the lumen area of Tet group was significantly increased than that of injured group at day 28. ②Compared with the injured group, the expression of SMa-actin, PCNA, p38MAPK and MKP-1 of vascular wall in Tet group was no difference, and the neointimal proliferation condition was also basically as same as injured group at day 7 after injury. The expression of PCNA and p38MAKP in Tet group was obviously lower than that in injured group, and the expression of MKP-1 in Tet group was obviously higher than that in injured group at days 14 and 28 after injury. The expression of SMa-actin in Tet group was slightly higher than that in injured group at days 14 and 28 after injury. Conclusions： Tet could reduce neointimal proliferation by inhibiting VSMCs phenotypic modulation and p38MAPK signaling transduction pathway as well as its down regulation.

Polarizing the immune system towards neuroprotection in brain ischemia

The development of ischemic brain damage is dramatically affected by the immune system,whose activation occurs immediately after the insult and may last for several days,involving a complex interplay between soluble and cellular mediators（Amantea et al.,2015）.Accordingly,recent expression profiling studies have revealed that the majority of the genes modulated in the blood of stroke patients participate in the regulation of innate immune responses（Brooks et al.,2014）.