Zinc Ion Inhibits Macrophage Foaming during Atherosclerosis / 中山大学学报(医学科学版)

@#【Objective】To investigate the effects of zinc on the formation of atherosclerotic macrophage foaming and plaque formation and its mechanism.【Methods】The macrophage foaming model was established by stimulating THP-1cells with oxLDL. The degree of foaming in different zinc concentrations of 0，30 and 60 μmol/Lwas detected by oil red Ostaining and the intake of lipid by foam cells was measured by DiI-oxLDL fluorescence. The relevant scavenger protein ex⁃pression of CD36，SR-A was detected by immunoblotting. The relative expression level of zinc ion transporters was detect⁃ed by real-time fluorescent quantitative PCR. ApoE-/- mice were randomly divided into 4 groups，the normal feed group（Chow group），the high-fat zinc-deficient group（HFD-ZnD），and the high-fat normal zinc group（HFD），high-fatand zinc-supplement group（HFD-ZnS），blood lipids and the protein of the mice aorta were detected in the 13 week.【Results】Compared with the normal zinc group，the oil red O density increased（P < 0.05），and add zinc ion decreased the intake of the DiI-oxLDL by foam cells（P < 0.01）. In the 0 μmol/L zinc group，the SR-A and CD36 protein expressionin the foam cells increased（P < 0.05）and 15μmol/L Zn2+ treatment before stimulating with oxLDL reduced the contentsof SR-A and CD36 proteins（P < 0.05）. Compared the oxLDL-treated group with the control group，the mRNA expres⁃sion levels of ZIP10，ZIP12 and ZIP14 increased，and the mRNA expression levels of ZIP4，ZIP7 and ZIP8 decreased（P < 0.05）；while the mRNA expression of ZnT4 was up-regulated（P < 0.01），and the mRNA expression of ZnT1 was down-regulated（P < 0.05）. Compared with Chow group，low density lipoprotein cholesterol（LDL-C），total cholesterol（TC）and triglyceride（TG）were increased in HFD group and HFD-ZnD group，respectively（P < 0.05）；HFD-ZnD group High-density lipoprotein cholesterol（HDL-C）was significantly elevated. Moreover，the LDL-C of the HFD-ZnS group was significantly lower than that of the HFD-ZnD group（P < 0.05）. The SR-A protein of the mice aorta of the HFD and HFD-ZnD group increased compared to the Chow group（P < 0.01），HFD-ZnS could restrain the increase（P < 0.05）. Compared with the Chow group，the ratio of plaque area in the aorta to the total arterial lumen area was significantly in⁃creased in the HFD-ZnD group（P < 0.01），and HFD-ZnS significantly inhibited this increase（P < 0.01）.【Conclusions】 Extracellular zinc deficiency aggravates lipid deposition in macrophages，and the mechanism may be regulated by up-reg⁃ulating the scavenger receptor CD36 and SR-A. Zinc ion transporters are involved in macrophage foaming and formation ofarterial plaques. Zinc deficiency can increase LDL-C and promote the increase of arterial plaque induced by high-fat diet.

Knockdown of Chloride Channel-3 Inhibits Breast Cancer Growth In Vitro and In Vivo / 한국유방암학회지

PURPOSE: Chloride channel-3 (ClC-3) is a member of the chloride channel family and plays a critical role in a variety of cellular activities. The aim of the present study is to explore the molecular mechanisms underlying the antitumor effect of silencing ClC-3 in breast cancer. METHODS: Human breast cancer cell lines MDA-MB-231 and MCF-7 were used in the experiments. Messenger RNA and protein expression were examined by quantitative real-time polymerase chain reaction and western blot analysis. Cell proliferation was measured by the bromodeoxyuridine method, and the cell cycle was evaluated using fluorescence-activated cell sorting. Protein interaction in cells was analyzed by co-immunoprecipitation. Tumor tissues were stained with hematoxylin-eosin and tumor burden was measured using the Metamorph software. RESULTS: Breast cancer tissues collected from patients showed an increase in ClC-3 expression. Knockdown of ClC-3 inhibited the secretion of insulin-like growth factor (IGF)-1, cell proliferation, and G1/S transition in breast cancer cells. In the mouse xenograft model of human breast carcinoma, tumor growth was significantly slower in animals injected with ClC-3-deficient cells compared with the growth of normal human breast cancer cells. In addition, silencing of ClC-3 attenuated the expression of proliferating cell nuclear antigen, Ki-67, cyclin D1, and cyclin E, as well as the activation of extracellular signal-regulated protein kinases (ERK) 1/2, both in vitro and in vivo. CONCLUSION: Together, our data suggest that upregulation of ClC-3 by IGF-1 contributes to cell proliferation and tumor growth in breast cancer, and ClC-3 deficiency suppresses cell proliferation and tumor growth via the IGF/IGF receptor/ERK pathway.

Phytoestrogen genistein supplementation increases eNOS and decreases caveolin-1 expression in ovariectomized rat hearts / 生理学报

This study examined whether genistein influences the production of nitric oxide (NO) and expression of endothelial nitric oxide synthase (eNOS) and the modulators of eNOS activity in ovariectomized (OVX) rat hearts. Female mature Sprague-Dawley rats were subjected to bilateral ovariectomy, OVX rats were randomly divided into four groups: 17beta-estradiol (0.1 mg/kg, s.c. daily) was used as the positive control; low dose of genistein (0.5 mg/kg, s.c. daily); high dose of genistein (5.0 mg/kg, s.c. daily) and model. Sham operations as controls, the treatment lasted 6 weeks. Blood pressure, heart rate, plasma estradiol, heart and uterine weights were measured. Nitrite production in the myocardium was determined by nitrate reductase method. Protein level of eNOS, caveolin-1 and calmodulin was determined by Western blot. The results showed that nitrite production and eNOS protein in homogenized ventricular tissue was attenuated by approximately 53% and 67% in OVX rats compared with those in sham rats, respectively. Genistein increased nitrite production in rat heart in a dose-dependent manner, genistein at the dose of 5 mg/kg.d(-1) resumed nitrite production to a level similar to that in sham operated rats. Administration of genistein also increased eNOS protein expression in OVX rats myocardium with a concomitant decrease in the expression of caveolin-1, an endogenous eNOS inhibitory protein. Another eNOS stimulatory protein, calmodulin, was unchanged in these treatments. These effects were also observed in rats treated with 17beta-estradiol. Genistein at the dose of 5.0 mg/kg.d(-1) augmented uterine weight but this side effect in reproductive system was less than that of 17beta-estradiol. These results suggest that genistein supplementation and estrogen replacement therapy directly increase eNOS functional activity and NO production in the hearts of the OVX rats, but genistein has less side effects on the reproductive system than 17beta-estradiol.