Rules and characteristics of crystallization inhibition of cellulose polymers against drugs in supersaturated states / 药学学报

This study aims to explore the characteristics of crystallization inhibition by cellulose polymers at the supersaturated states of drugs. The study was performed by simulating supersaturated process and preparing supersaturated drug solid, and was carried out by measuring the content of drugs at different time points using dissolution apparatus. The types, amounts, ionic intensity and viscosity of cellulose polymers were examined to assess the crystallization inhibition effect on BCS II class drug indomethacin. HPMC E15 exhibited the strongest crystallization inhibition effect. The more added, more obvious crystallization suppression was observed against indomethacin. The decrease in viscosity and increase in ionic intensity led to an enhanced inhibition. The research provides a scientific guide for the crystallization inhibition of supersaturated drug by cellulose polymers.

Pharmacokinetics and tissue distribution of mitomycin amphiphilic chitosan polymeric micelles in rats / 中国药学杂志

OBJECTIVE: To investigate the pharmacokinetics and tissue distribution of mitomycin amphiphilic chitosan polymeric micelles (MMC-ACPM) in rats. METHODS: Mitomycin injection (MMC-INJ) and MMC-ACPM were administered to rats through tail vein at the dosage of 0. 5 mg · kg-1. An ultra-fast liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was established to determine the concentration of mitomycin (MMC) in plasma and tissues of rats. RESULTS: The t1/2(β) of MMC-INJ and MMC-ACPM in plasma were estimated to be (0.67 ± 0.36) and (3.33 ± 1.47) h, respectively. The AUC0→∞ were calculated to be (120.94 ± 13.77) and (140.95 ± 11.56) ng · mL-1 · h-1, respectively. The MRT were (0.83 ±0.13) and (1.56 ± 0.22) h, and CL were (0.005 ± 0.001) and (0.003 ± 0.001) L · h-1 · kg-1, respectively. Compared with MMC-INJ group, MMC-ACPM group had lower concentrations of MMC in heart, liver, spleen, lung, and kidney of rats. CONCLUSION: MMC-ACPM can prolong the circulation of MMC in vivo, improve its bioavailability, and reduce the accumulation in liver and kidney, which can improve curative effects and reduce toxicity.

Study on the signalling pathway of inhibitory effect of adreno-medullin on the growth of cultured glomerular mesangial cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Adrenomedullin (ADM), a potent hypotensive small peptide, was recently found to inhibit the proliferation of glomerular mesangial cells (MsC) in vitro and to attenuate glomerular lesions in vivo, however the mechanisms remain poorly understood. In this study, we attempted to elucidate them using molecular signal transduction.</p><p><b>METHODS</b>Cultured rat MsC were treated with ADM and several inhibitors of signalling molecules. Methyl thiazoleterazolium (MTT) assay and BrdU incorporation method were employed for examining MsC proliferation. Western blot analysis was used for detecting total mitogen activated protein kinases (t-MAPKs) and phosphorylated MAPKs (p-MAPKs) proteins.</p><p><b>RESULTS</b>ADM suppressed MsC proliferation in a concentration- and time-dependent fashion. This response was inhibited by ADM receptor antagonist CGRP8-37 and a potent protein kinase-A (PKA) inhibitor, H89. Forskolin, a direct adenylate cyclase activator, also significantly inhibited MsC proliferation. SB203580, a P38MAPK inhibitor, and U0126, a MEK inhibitor, both completely blocked ADM mediated responses in MsC. However, curcumin, a SAPK/JNK inhibitor, and GF109203X, a potent protein kinase-C (PKC) inhibitor, had no effect on MsC growth. Western blot analysis showed that ADM did not change the expression of t-MAPKs but increased p-SAPK/JNK and p-P38MAPK levels and decreased p-ERK level. These responses were inhibited by CGRP8-37. All these kinase phosphorylations, except for the increase in p-SAPK/JNK, could be stimulated using forskolin. In addition, only ADM mediated changes in ERK and P38MAPK phosphorylations were inhibited by H89. GF109203X did not affect ADM induced changes in three p-MAPKs expressions.</p><p><b>CONCLUSIONS</b>ADM inhibits MsC proliferation possibly through cAMP-PKA pathway. Both phosphorylations of ERK and P38MAPK pathways were necessary in mediating the antiproliferative response of ADM. It does not preclude the involvement of cAMP independent pathways in the ADM mediated responses.</p>

Effects of aldose reductase on the expression of fibronectin and collagen IV in cultured rat renal mesangial cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the effect of aldose reductase (AR) on expression of fibronectin and collagen IV in cultured rat renal mesangial cells (MsC).</p><p><b>METHODS</b>AR expression plasmid vector (pCDNA3-AR) was constructed by restriction endonuclease digestion and ligation procedures. Stable expression of AR in MsC was established by Lipofectin transfection. Western blot and immunofluorescence analyses were performed to verify the transfection efficiency. Expression of fibronectin and collagen IV proteins were analyzed using Western blot.</p><p><b>RESULTS</b>Expression of fibronectin and collagen IV in naive MsC treated with TGF-beta1 was upregulated in comparison to that of the untreated naive MsC (P < 0.01). MsC transfected with pCDNA3-AR showed a remarkable increase of expression of fibronectin and collagen IV (P < 0.01). Aldose reductase inhibitors (Sorbinil and Zopolrestat) significantly inhibited the expression of fibronectin and collagen IV in naive MsC (P < 0.05).</p><p><b>CONCLUSIONS</b>Overexpression or inhibition of AR activity significantly alters the expression of fibronectin and collagen IV proteins in cultured rat MsC, suggesting that AR plays a significant role in the pathogenesis of glomerulosclersis.</p>

Significance of MMP-2 and TIMP-2 mRNA expressions on glomerular cells in the development of glomerulosclerosis / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To study the expressions of MMP-2 and TIMP-2 mRNA on cultured rat mesangial cells (MsC) and in human diseased glomeruli, and to explore their significance in the development of glomerulosclerosis.</p><p><b>METHODS</b>The expressions of MMP-2, TIMP-2, and Col IV mRNA on cultured rat MsC stimulated by IL-1 or/and TGF-beta1 were investigated through Northern blot analysis. The levels of MMP-2 and TIMP-2 mRNA expressions and immunoreactivity of PCNA and Col IV in human diseased glomeruli from renal biopsies of lupus nephritis (LN) patients were examined by in situ hybridization and immunohistochemistry, respectively.</p><p><b>RESULTS</b>The levels of MMP-2, TIMP-2, and Col IV mRNA expressions were markedly increased on cultured rat MsC stimulated by IL-1 or/and TGF-beta1. Meanwhile, upregulation of MMP-2 and TIMP-2 mRNA expressions was confirmed in diseased glomeruli from patients with various subtypes of LN, and was closely related to the positive cell number of PCNA presentation and deposition of Col IV in glomeruli.</p><p><b>CONCLUSION</b>The results suggest that the over-expressions of MMP-2 and TIMP-2 mRNA on glomerular cells might play a critical role in the development of glomerulosclerosis.</p>

Expression of CCAAT/enhancer-binding protein in cultured rat hepatic stellate cells and its significance / 中华肝脏病杂志

<p><b>OBJECTIVE</b>The expression of C/EBPalpha protein and mRNA during automatically activation process in primary cultures of HSCs were observed in order to explore its possible association with the proliferation and activation of HSCs.</p><p><b>METHODS</b>Immunocytochemistry, Western blot and RT-PCR were used to evaluated the expression of C/EBPalpha protein and mRNA; as well as the expression of alpha-SMA, Desmin, MMP2, type I procollagen (alpha1). The eukaryotic vector harboring the full length cDNA of C/EBPalpha was transfected into activated HSC, then immunocytochemistry was applied to confirm the transfection and evaluate the effect of transfection on the proliferation of HSC by calculating the PCNA-positive cells. The morphological changes of HSC were observed by use of phase-contrast microscope.</p><p><b>RESULTS</b>Constitutive expression of mRNA and protein of C/EBPalpha were detected in primarily cultured HSCs, and the protein was seen in both nuclei and cytoplasm with the latter being dominant. Their expression levels reached highest at day 2 of the culture, then decreased gradually when continually cultured to the day 4, 7, 10, on the other hand, the expression of alpha-SMA, MMP2 and ColI(alpha1) increased steadily. Transient transfection was verified by the fact that much more and stronger C/EBPalpha stain was observed in transfected HSCs than in void-vector transfected cells. In C/EBPalpha gene transfected HSCs, the number of PCNA-positive cells dramatically decreased compared with the void-vector transfected cells 24h after transfection. In addition, the C/EBPalpha gene transfected HSCs died 36 h after transfection, a few surviving cells became longer and thinner in morphology, however the void-vector transfected cells almost all remained alive.</p><p><b>CONCLUSIONS</b>C/EBPalpha was likely involved in the HSCs activation, and over-expressed C/EBPalpha by transfection had inhibitory influence on the proliferation of cultured rat HSCs.</p>

The antagonistic effect on anti-thy-1 serum-induced nephritis of rats injected by decorin-transfected mesangial cells vector / 中华病理学杂志

<p><b>OBJECTIVES</b>To inject decorin-transfected mesangial cells (MsC) vector into the kidneys of rats with anti-thy-1 serum-induced nephritis via left renal artery and observe the survival condition of MsC vector and its influence on glomerular lesions in rats with anti-thy-1 serum induced nephritis.</p><p><b>METHODS</b>Rat mesangio-proliferative glomerulonephritis was established by tail intravenous injection with rabbit anti-thy-1 serum (ATS). Decorin-transfected MsC was injected into rat kidneys via left renal artery. Primary culture, immunostaining for BrdU and decorin of transfected MsC lines were performed to observe their survival. Immunohistochemistry with image analysis was performed to detect the expression of BrdU, alpha-SMA, decorin, TGF-beta1, FN and ColIV in diseased glomeruli.</p><p><b>RESULTS</b>Rat anti-thy-1 serum-induced nephritis identified by pathological examination was successfully established by injecting rabbit ATS, and decorin transfected MsC vector was transfused to rat glomeruli via left renal artery. The active growth and positive expressions of BrdU and decorin proteins on the nuclei and cytoplasms of ex vivo MsC were observed respectively. TGF-beta1, FN, ColIV expressions in diseased glomeruli of rats with ATS nephritis were decreased significantly at day 4 (TGF-beta1, P < 0.05) and day 2 (FN and ColIV, P < 0.01) respectively, compared to uninjected kidneys.</p><p><b>CONCLUSIONS</b>MsC vector is successfully transferred to the glomeruli of experimental rats via left renal artery injection with no affect on cell survival. Decorin protein is expressed on the transfected MsC and shows antagonistic effect on the glomerular lesions of ATS rats. It suggests that the use of ex vivo MsC vector system can provide useful experimental basis for gene therapy of kidney disease in animal model.</p>

Changes of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 expressions on cultured rat mesangial cells transfected with Smad 7 vector / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) expressions in the cultured rat mesangial cells (MsC) transfected with Smad 7 vector and to elucidate the mechanism of Smad 7 in blocking tissue fibrosis.</p><p><b>METHODS</b>Lipofectin method was used to transfect Smad 7 vector into MsC. Western blot and RT-PCR analyses were then used to detect Smad 7 protein and mRNA expression levels. The expressions of MMP-2 and TIMP-2 were determined by Western blot, RT-PCR and zymography assay.</p><p><b>RESULTS</b>Two MsC clones (S-22, S-26) with Smad 7 overexpression were successfully established. The two clones showed an increased expression of MMP-2 protein and enhanced enzyme activity. The expressions of TIMP-2 protein and mRNA however were suppressed.</p><p><b>CONCLUSIONS</b>It is possible that Smad 7 can alleviate the development of tissue fibrosis by upregulating the expression of MMP-2 and downregulating the expression of TIMP-2 in mesangial cells.</p>

Effect of transforming growth factor beta1/Smad signaling pathway on the expression and enzymatic activity of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 in cultured rat mesangial cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the effect of transforming growth factor (TGF) beta1/Smad signaling pathway on the expression and enzymatic activity of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in cultured rat mesangial cells (MsC).</p><p><b>METHODS</b>Lipofectin method was used to transfect Smad 2, Smad 3 and Smad 7 vectors into MsC; and immunofluorescence, RT-PCR and Western blot analysis were used to detect their transfection efficiency. The expression and enzymatic activity of MMP-2 and TIMP-2 were determined by Western blot, zymography or reverse zymography assay.</p><p><b>RESULTS</b>MsC transfected with Smad 2 gene showed slightly increased expression and enzymatic activity of both MMP-2 and TIMP-2, which was more obvious upon stimulation by TGF-beta1. MsC transfected with Smad 3 gene showed a slight upregulation of TIMP-2 expression and its enzymatic activity, which was enhanced after TGF-beta1 stimulation. There was however no change in MMP-2 expression and its enzymatic activity. On the other hand, MsC transfected with Smad 7 gene showed a decrease in MMP-2 and TIMP-2 expression and enzymatic activity, which was especially obvious after stimulation by TGF-beta1.</p><p><b>CONCLUSIONS</b>TGF-beta1/Smad signaling pathway may play an important role in the pathogenesis of glomerulosclerosis, probably via MMP-2 and TIMP-2 expression and the associated enzymatic activity.</p>

Effect of RAR-beta transfection on the proliferation and phenotype of rat hepatic stellate cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effect of RAR-beta transfection plus treatment with the corresponding ligand ATRA on the proliferation and phenotype of platelet-derived growth factor (PDGF)-activated hepatic stellate cells (HSC).</p><p><b>METHODS</b>PDGF-activated hepatic stellate cells of rats were transfected with eukaryotic expression vector pCMV-script-RAR-beta, which was verified by western blot. The proliferation of transfected HSC was assayed by BrdU incorporation as well as MTT methods. Their phenotype (alpha-SMA and desmin) was observed by immunocytochemistry assay with image analysis and RAR-beta protein expression was detected by western blot.</p><p><b>RESULTS</b>Transfection of RAR-beta gene and treatment with ligand ATRA could increase the expression of RAR-beta protein for at least 144h and inhibit the proliferation and the expression of alpha-SMA and desmin in PDGF-activated HSC. Significant statistical differences were perceived comparing with sham-transfected, only-PDGF treated, non-ligand treated and irrelevant ligand-treated HSC.</p><p><b>CONCLUSIONS</b>Transfected with RAR-beta gene as well as using related ligand ATRA could suppress the proliferation and reverse the activation phenotype of activated HSC.</p>