Recent advances in nephronectin / 生理学报

Nephronectin (NPNT) is a novel extracellular matrix protein and a new ligand of integrin α8β1. Recent studies showed that NPNT is highly expressed in kidney, lung, thyroid, etc, and it may play an important role in many pathological conditions. NPNT is involved in the process of kidney development and acute kidney injury, regulates proliferation and differentiation of osteoblast, and induces the vasculogenesis in vitro. NPNT may play a key role in pathological osteoporosis and therefore be a new therapeutic target of bone diseases. NPNT gene variants are not only associated with lung function, but also potentially implicated in chronic airway diseases development. Moreover, NPNT is also an important factor that mediates pathology of cardiac, epidermis, breast, liver and teeth diseases. In this paper, we reviewed some research progresses on the structure, distribution, physiological and pathophysiological functions of NPNT.

Primary cell culture and identification methods of rat pulmonary arterial smooth muscle cells / 中国应用生理学杂志

<p><b>OBJECTIVE</b>Set up a method to isolate and identify the small pulmonary arterial smooth muscle cells (PASMCs) in vitro.</p><p><b>METHODS</b>In sterile conditions, separated the male SD rat pulmonary artery, digested by collagenase I and cultured primary PASMCs. Measured cell viability; observed by phase contrast microscope; identified by immunocytochemistry and immunofluorescence staining as a label for smooth muscle alpha-actin.</p><p><b>RESULTS</b>PASMCs were identified by morphology and immunocytochemistry, immunofluorescence staining, with the cell viability is over 96.5%. The primary culture could be subcultured after 4-7 days and successfully passaged without change in morphology and growth characteristic.</p><p><b>CONCLUSION</b>This technique has advantage of the method is simple, short cultivate, good reproducibility, the primary cultured PASMCs quantity and the rapid growth.</p>

The effect of chimonin on collagen metabolism of pulmonary arterioles in chronic hypoxic rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the effect and mechanism of chimonin on pulmonary arterioles I and III type collagen metabolism in pulmonary hypertension rats induced by chronic hypoxic hypercapnia.</p><p><b>METHODS</b>Thirty-six Sprague-Dawley rats were randomly divided into three groups: normal control group(A), hypoxic hypercapnic group(B), hypoxic hypercapnia + chimonin group(C). Collagen I, III and their mRNA, Blood CO concentration (COHb%), activity of HO-1 in blood serum and lung homogenate, content of hydroxyproline in lung homogenate, pulmonary arteriole micromorphometric index were observed.</p><p><b>RESULTS</b>Hypoxic hypercapnic rats's mPAP, Hyr of lung homogenate, content of I type collagen and I type collagen mRNA in pulmonary arterioles, were significantly higher than those in control group, pulmonary vessel remodeling of hypoxic hypercapnic rats was significant, those changes in hypercapnia + chimonin group were significantly lower than those in hypoxic hypercapnic group. Blood CO concentration, activity of HO-1 in blood serum and lung homogenate in rats of hypoxic hypercapnic rats were significantly higher than those of control group, and those of hypercapnia + chimonin group were even higher than hypoxic hypercapnic group (P < 0.01). There was no significant difference in mCAP, content of III type collagen and their mRNA in three groups (P > 0.05).</p><p><b>CONCLUSION</b>Chimonin can reduce pulmonary hypertension and pulmonary vessel remodeling induced by hypoxic hypercapnia through inhibiting proliferation of collagen I, the mechanism maybe is up regulating endogenous carbon monoxide system.</p>

Effects and mechanism of oridonin on pulmonary hypertension induced by chronic hypoxia-hypercapnia in rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary arterial hypertension (PAH) is characterized by suppressing apoptosis and enhancing cell proliferation in the vascular wall. Inducing pulmonary artery smooth muscle cells (PASMC) apoptosis had been regarded as a therapeutic approach for PAH. Oridonin can cause apoptosis in many cell lines, while little has been done to evaluate its effect on PASMC.</p><p><b>METHODS</b>Thirty male Sprague-Dawley rats were randomly assigned to three groups: normal control (NC); hypoxia-hypercapnia (HH); Hypoxia-hypercapnia + oridonin (HHO). Rats were exposed to hypoxia-hypercapnia for four weeks. Cultured human PASMC (HPASMC) were assigned to three groups: normoxia (NO); hypoxia (HY); hypoxia + oridonin (HO). The mean pulmonary artery pressure, mass ratio of right ventricle over left ventricle plus septum (RV/(LV + S)), the ratio of thickness of the pulmonary arteriole wall to vascular external diameter (WT%) and the ratio of the vessel wall area to the total area (WA%) were measured. Morphologic changes of pulmonary arteries were observed under light and electron microscopes. The apoptotic characteristics in vitro and in vivo were detected.</p><p><b>RESULTS</b>The mPAP, RV/(LV + S), WT%, and WA% in the HH group were significantly greater than those in the NC (P < 0.01) and HHO groups (P < 0.01); the activities of caspase-3 and caspase-9, and the expressions of Bax, cyt-C and apoptotic index (AI) in the group HH were less than those in the NC and HHO groups; and the expression of Bcl-2 in group HH was greater than that in the NC and HHO groups. HPASMC mitochondrial membrane potentials in group HO was lower than in group HY (P < 0.01), and cyt-C in the cytoplasm, AI, and caspase-9 in the HO group were greater than that in the HY group (P < 0.01), but the expression of Bcl-2 in the HO group was less than that in the HY group (P < 0.05).</p><p><b>CONCLUSIONS</b>The results suggest that oridonin can lower pulmonary artery pressure effectively, and inhibit pulmonary artery structural remodeling by inducing smooth cell apoptosis via a mitochondria-dependent pathway.</p>