Effect of Cordyceps sinensis powder on renal oxidative stress and mitochondria functions in 5/6 nephrectomized rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of Cordyceps sinensis (CS) powder on renal oxidative stress and mitochondria functions in 5/6 nephrectomized rats, and to primarily explore its possible mechanisms.</p><p><b>METHODS</b>Totally 30 male Sprague-Dawley rats were divided into the sham-operation group, the model group, and the treatment group by random digit table, 10 in each group. A chronic kidney disease (CKD) rat model was prepared by one step 5/6 nephrectomy. Rats in the treatment group were intragastrically administered with CS powder solution at the daily dose of 2 g/kg, once per day. Equal volume of double distilled water was intragastrically administered to rats in the sham-operation group and the model group. All medication lasted for 12 weeks. The general condition of rats, their body weight, blood pressure, 24 h proteinuria, urinary N-acetyl-β-D-glucosaminidase (NAG), serum creatinine (SCr) , and blood urea nitrogen (BUN) were assessed before surgery, at week 2, 4, 6, 8, 10, and 10 after surgery. Pathological changes of renal tissues were observed under light microscope. Morphological changes of mitochondria in renal tubular epithelial cells were observed under transmission electron microscope. Activities of antioxidant enzymes including reduced glutathione (GSH), manganese superoxide dismutase (MnSOD), and malondialdehyde (MDA) in fresh renal tissue homogenate were detected. Mitochondria of renal tissues were extracted to detect levels of mitochondrial membrane potential and changes of reactive oxygen species (ROS). And expressions of cytochrome-C (Cyto-C) and prohibitin in both mitochondria and cytoplasm of the renal cortex were also measured by Western blot.</p><p><b>RESULTS</b>(1) Compared with the sham-operation group, body weight was significantly decreased at week 2 (P <0. 01), but blood pressure increased at week 4 (P <0. 05) in the model group. Compared with the model group, body weight was significantly increased at week 12 (P <0. 01), but blood pressure decreased at week 8 (P < 0. 01) in the treatment group. (2) Compared with the sham-operation group, 24 h proteinuria, urinary NAG, blood SCr and BUN significantly increased in the model group (all P <0. 01). Compared with the model group, blood and urinary biochemical indices all significantly decreased in the treatment group (all P <0. 01). (3) Results of pathological renal scoring: Glomerular sclerosis index, scoring for tubulointerstitial fibrosis, degree of tubulointerstitial inflammatory infiltration were all obviously higher in the model group than in the sham-operation group (all P <0. 01). All the aforesaid indices were more obviously improved in the treatment group than in the model group (all P <0. 01). (4) Compared with the sham-operation group, activities of MnSOD and GSH-Px were significantly reduced, but MDA contents obviously increased in the renal cortex of the model group (all P <0. 01). Compared with the model group, activities of MnSOD and GSH-Px obviously increased (P <0. 05, P <0. 01), but MDA contents obviously decreased in the renal cortex of the treatment group (P <0. 01). (5) Compared with the sham-operation group, the mitochondrial membrane potential significantly decreased, but ROS levels significantly increased in the model group (all P <0.01). Compared with the model group, mitochondrial transmembrane potential increased in the treatment group, thereby inhibiting the tendency of increased production of ROS (both P < 0. 01). (6) Results of Western blot showed that, compared with the sham-operation group, expression levels of mitochondrial Cyto-C and Prohibitin were significantly reduced in the renal cortex (P <0. 01), but significantly elevated in the cytoplasm of the model group (P <0. 01). Compared with the model group, each index was obviously improved in the treatment group with statistical difference (P <0. 05, P <0. 01).</p><p><b>CONCLUSION</b>CS powder had renal protection, and its mechanism might partially depend on in- hibition of oxidative stress and protection for mitochondria.</p>

High glucose and tea polyphenols on expression of matrix metalloproteinase-2 and extracellular matrix metalloproteinase inducer in human umbilical vein endothelial cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of high glucose on expression of matrix metalloproteinase-2 (MMP-2) and extracellular matrix metalloproteinase inducer (EMMPRIN) in human umbilical vein endothelial cells (HUVECs).</p><p><b>METHODS</b>HUVECs were cultured in DMEM media containing high glucose with or without polyphenols for 24 hours respectively. The activity of MMP-2 in the supernatant was detected by zymography. The expression of MMP-2 mRNA and protein in HUVECs were detected by RT-PCR and Western blot respectively. The expression of EMMPRIN mRNA and protein in the cells were determined by RT-PCR as well as immunocytochemistry and Western blot respectively.</p><p><b>RESULTS</b>The expression of MMP-2 and EMMPRIN mRNA were suppressed by a high concentration of glucose. Both the MMP-2 activity and protein level of EMMPRIN expression were also significantly decreased. Polyphenols abolished all the above changes of HUVECs induced by a high glucose level (P < 0.05).</p><p><b>CONCLUSIONS</b>An acute high glucose stimulation down-regulates the activity of MMP-2, the expressions of MMP-2 and EMMPRIN at RNA and protein levels in the endothelial cells, which may play an important roles in diabetic vascular complications in the early phase. Polyphenols treatment can diminish the detrimental effects of high glucose on HUVECs.</p>

Fibroblasts-colorectal cancer cells interaction induces the expression of IGFBP7 / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the impact of intracellular interaction between fibroblasts and colorectal cancer cells on the expression of insulin growth factor binding protein7 (IGFBP7).</p><p><b>METHODS</b>Colorectal cancer cells SW480 were cultured with or without fibroblasts HELF cells in RPMI 1640 medium for 0 h, 48 h, 7 2 h and 96 h, respectively. By RT-PCR and immunohistochemical staining methods,the expression of IGFBP7 was detected in mono-and co-cultured cells.</p><p><b>RESULT</b>When SW480 cells were co-cultured with HELF cells, IGFBP7 expression in SW480 cells was significantly upregulated. Furthermore, IGFBP7 was induced in HELF cells both at mRNA and protein levels, which did not express when cells were mono-cultured.</p><p><b>CONCLUSION</b>Fibroblasts-colorectal cancer cells interaction induces the expression of IGFBP7, which indicates tumor-stroma interactions may play an important role in colorectal cancer development.</p>

Increased expression of extracellular matrix metalloproteinase inducer through interaction between fibroblasts and colonic cancer cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the expression of extracellular matrix metalloproteinase inducer gene (EMMPRIN) regulated by the interactions between fibroblasts and colon cancer cells, and to study its role in the invasion and metastasis of colon cancer.</p><p><b>METHODS</b>Colon cancer cells (SW480) were co-cultured with fibroblasts (HELF) in RPMI 1640 media for 0, 12, 24 and 48 hours. The expression of EMMPRIN in SW480 cells and HELF cells was documented by RT-PCR and immunocytochemistry.</p><p><b>RESULTS</b>The mRNA and protein expressions of EMMPRIN in SW480 cells were remarkably increased by the co-culturing with HELF cells. Although without the endogenous expression, HELF cells began to express EMMPRIN in a time-dependent manner after being co-cultured with SW480 cells.</p><p><b>CONCLUSIONS</b>Intercellular interactions between colon cancer cells and fibroblasts not only up-regulate the EMMPRIN expression in SW480 cells, but also induce its expression in HELF cells. Such interactions may play a crucial role in the invasion and metastasis of colon cancer.</p>

Hypoxia induced by CoCl2 influencing the expression and the activity of matrix metalloproteinase-2 in rat hepatic stellate cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the effects of hypoxia induced by cobalt chloride on the expression and the activity of matrix metalloproteinase-2 (MMP-2) in rat hepatic stellate cells (HSC-T6) and to clarify the possible mechanisms.</p><p><b>METHODS</b>HSC-T6 cell line was grown in Dulbecco's modified Eagle medium with 10% fetal calf serum at 37 degrees C and 5% CO2. When reaching confluence, the cells were incubated with serum-free medium in the presence of cobalt chloride (0, 50, 100, 200 micromol/L) for six hours, and then the supernatant and the cells were harvested. The expression of the MMP-2 mRNA and HIF-1alpha protein in HSC-T6 cells was detected using RT-PCR and Western blot respectively. The activity of the MMP-2 in the supernatant was detected by zymography. The binding reaction between HIF-1a protein and MMP-2 gene sequence was investigated by electrophoresis mobility shift assay.</p><p><b>RESULTS</b>When the concentration of CoCl2 increased from 0 micromol/L to 200 micromol/L, the expressions of MMP-2 mRNA (the rate of light density) were increased from 0.53+0.12 to 1.57+0.11 and the differences among these four groups were significant (F=34.21). The activity of MMP-2 (the value of light density*band area) decreased gradually from 84.49+5.38 to 53.70+3.42, and the differences among these four groups were also significant (F=29.54). The expressions of HIF-1a were increased gradually with the increase of the CoCl2 concentration. The shift band in the lane of the nuclear protein extraction and the MMP-2 probe containing hypoxia response element showed delays when compared with the lane of the sole probe, and the binding was partially abolished when competing sense oligonucleotides were used.</p><p><b>CONCLUSIONS</b>Our results suggest that chemical hypoxia can up-regulate the expression of MMP-2 mRNA and decrease the activity of the enzyme. HIF-1alpha may play a part in the regulation of MMP-2 transcription under hypoxic conditions.</p>

Neuroprotective effects of Astragulus membranaceus on hypoxia-ischemia brain damage in neonatal rat hippocampus / 中国中药杂志

<p><b>OBJECTIVE</b>To study neuroprotective effects of astragulus membraneaceus on a neonatal rat hippocampus of hypoxia-ischemia brain damage (HIBD).</p><p><b>METHOD</b>The neonatal hypoxia-ischemia model was established with 7-day-old rat pups. Brain injury was examined by neuron death rate in the hippocampal CA1 area. Caspase-3 (cysteinyl aspartate-specific proteinase) mRNA expression in ipsilateral hippocampal was measured by half-quantitative reverse transcription and polymerization chain reaction (RT-PCR). 90-day-old rats were used in tri-equal-arm maze to observe discrimination learning ability. Sham, model and astragulus-membraneaceus treated groups were set up.</p><p><b>RESULT</b>In model group, caspase-3 mRNA showed an increase at 6h, with maximum arrivimg at 24 h - 48 h after HI. In astragulus-membraneaceus treated group, neurons death rate and caspase-3 mRNA were significantly reduced by astragulus membraneaceus, and discrimination learning ability of developed rats were improved obviously.</p><p><b>CONCLUSION</b>Astragulus membraneaceus has a strong protective effect on neuronal damage in the immature rat hippocampus, which is ralated reducing caspase-3 expression.</p>