Phenotypic modulation of vascular smooth muscle cells in diabetes mellitus and intervention of traditional Chinese medicines / 中国中药杂志

Proliferation and migration of vascular smooth muscle cells (VSMC) are common pathological features of diabetic vascular complications,such as atherosclerosis and hypertension. Phenotypic modulation of VSMC is the basis for VSMC proliferation and migration. Therefore, studies on VSMC phenotypic modulation and its mechanisms in diabetes mellitus were of important significance to the prevention and therapy of diabetic vascular complications. This paper introduces VSMC phenotypic modulation and the underlying mechanisms in diabetes mellitus, and summarizes advance of studies on traditional Chinese medicine intervention upon VSMC phenotypic modulation, so as to provide reference for preventing and treating diabetic vascular complications with traditional Chinese medicines.

Inflammatory reaction versus endogenous peroxisome proliferator-activated receptors expression, re-exploring secondary organ complications of spontaneously hypertensive rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The chronic pathological changes in vascular walls of hypertension may exert destructive effects on multiple organ systems. Accumulating evidence indicates that inflammatory reactions are involved in the pathological changes of hypertension. Three peroxisome proliferator-activated receptors (PPARs) have been identified: PPARalpha, PPARbeta/delta, and PPARgamma, all of which have multiple biological effects, especially the inhibition of inflammation. The aim of this study was to evaluate PPAR isoforms expression profile in important organs of spontaneously hypertensive rats (SHR) and to understand the modulation of endogenous PPAR isoforms under inflammatory condition.</p><p><b>METHODS</b>Tissues (kidney, liver, heart, and brain) were dissected from SHR and age-matched control Wistar-Kyoto rats (WKY) to investigate the abundance of PPAR isoforms and PPAR-responsive genes (acyl-CoA oxidase and CD36). The expression of CCAAT/enhancer-binding protein delta (C/EBPdelta), which can trans-activate PPARgamma expression, was also observed. The inflammatory response was analyzed by the expression of inflammatory mediators inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, interleukin-1 beta (IL-1beta), and tumor necrosis factor alpha (TNFalpha), and formation of carbonyl and nitrated proteins.</p><p><b>RESULTS</b>The expressions of 3 PPAR isoforms and PPAR-responsive genes were markedly upregulated in SHR compared with those of WKY. Specifically, the expression of PPARalpha protein in the kidney, liver, heart and brain increased by 130.76%, 91.48%, 306.24%, and 90.70%; PPARbeta/delta upregulated by 109.34%, 161.98%, 137.04%, and 131.66%; PPARgamma increased by 393.76%, 193.17%, 559.29%, and 591.18%. In consistent with the changes in PPARgamma, the expression of C/EBPdelta was also dramatically elevated in SHR. Inflammatory mediators expressions were significantly increased in the most organs of SHR than WKY. As a consequence, increased formation of carbonyl and nitrated proteins were also observed in the most organs of SHR.</p><p><b>CONCLUSIONS</b>These findings suggest an enhanced inflammatory response in the organs of SHR, which might play a key role in pathogenesis of hypertension and secondary organ complications. Changes (increases) in PPARs expression may reflect a compensatory mechanism to the inflammatory status of hypertensive rats.</p>

Inflammation of different tissues in spontaneously hypertensive rats / 生理学报

The hypertension is one of chronic vascular diseases, which often implicates multiple tissues causing stroke, cardiac hypertrophy, and renal failure. A growing body of evidence suggests that inflammatory mechanisms are important participants in the pathophysiology of hypertension. In this study, the inflammatory status of these tissues (kidney, liver, heart, and brain) in spontaneously hypertensive rats (SHR) was analyzed and its molecular mechanism was explored. The tissues were dissected from SHR and age-matched control Wistar-Kyoto (WKY) rats to investigate the abundance of inflammation-related mediators (IL-1beta, TNFalpha, ICAM-1, iNOS, C/EBPdelta and PPARgamma). mRNA levels were determined by reverse transcription-polymerase chain reaction and protein expression was evaluated by Western blot. To evaluate the oxidative stress of tissues, carbonyl protein content and total antioxidant capacity of tissues were detected by spectrophotometry and ferric reduction ability power (FRAP) method. The results suggest that: (1) Expressions of inflammation-related mediators (IL-1beta, TNFalpha, ICAM-1, iNOS, C/EBPdelta and PPARgamma) in SHR were higher compared with those in WKY rats except no evident increase of IL-1beta mRNA in liver and brain in SHR. (2) Tissues in SHR contained obviously increased carbonyl protein (nmol/mg protein) compared to that in WKY rats (8.93+/-1.08 vs 2.27+/-0.43 for kidney, 2.23+/-0.23 vs 0.17+/-0.02 for heart, 13.42+/-1.10 vs 5.72+/-1.01 for brain, respectively, P<0.05). However, no evident difference in the amount of carbonyl protein in liver was detected between SHR and WKY rats. (3) Total antioxidant capacities of kidney, liver, heart and brain were markedly lower in SHR than that in WKY rats (P<0.05). Thus, the present data reveal a higher inflammatory status in the important tissues in SHR and indicate that inflammation might play a potential role in pathogenesis of hypertension and secondary organ complications.

Vasodilation effect of atropine on rat mesenteric artery / 药学学报

<p><b>AIM</b>To study the vasodilation effect of atropine and its mechanism.</p><p><b>METHODS</b>Isometric tension was recorded in isolated rat super mesenteric arteries precontracted by noradrenaline (NE) to study the vasodilation effect of atropine, and to investigate the role of endothelial cell and vascular smooth muscle cell on vasodilation.</p><p><b>RESULTS</b>Atropine was shown to significantly dilate the endothelium-intact and endothelium-denuded arteries precontracted by NE. Nomega-Nitro-L-arginine methyl ester (L-NAME, nitric oxide synthase inhabitor), indomethacin (cyclooxygenase inhibitor), propranolol (general beta adrenoceptor antagonist) and glibenclamide (ATP sensitive potassium channel inhibitor) showed no effect on vasodilation of atropine. Atropine did not affect the concentration-contraction curve of K+. However, atropine suppressed the contraction induced by NE and CaCl2, but not that by caffeine in the Ca+ -free Krebs solution.</p><p><b>CONCLUSION</b>Atropine showed significant vasodilation effect which may derive, in part, from endothelium. Besides, atropine could inhibit the receptor-mediated Ca2+ -influx and Ca2+ -release, which was inferred to the mechanism of atropine on vasodilation.</p>