SATB1/SLC7A11/HO-1 Axis Ameliorates Ferroptosis in Neuron Cells After Ischemic Stroke by Danhong Injection.

Neuronal damage after ischemic stroke (IS) is frequently due to ferroptosis, contributing significantly to ischemic injury. However, the mechanism against ferroptosis in IS remained unclear. The aim of this study was to investigate the potential mechanism of Danhong injection (DHI) and the critical transcription factor SATB1 in preventing neuronal ferroptosis after ischemic stroke in vivo and in vitro. The results showed that DHI treatment significantly reduced the infarct area and associated damage in the brains of the pMCAO mice, and enhanced the viability of OGD-injured neurons. And several characteristic indicators of ferroptosis, such as mitochondrial necrosis and iron accumulation, were regulated by DHI after IS. Importantly, we found that the expression and activity of SATB1 were decreased in the pMCAO mice, especially in neuron cells. Meanwhile, the SATB1/SLC7A11/HO-1 signaling pathway was activated after DHI treatment in ischemic stroke and was found to improve neuronal ferroptosis. Inhibition of SATB1 significantly reduced SLC7A11-HO-1 and significantly attenuated the anti-ferroptosis effects of DHI in the OGD model. These findings indicate that neuronal ferroptosis after IS can be alleviated by DHI through SATB1/SLC7A11/HO-1 pathway, and SATB1 may be an attractive therapeutic target for treating ischemic stroke.

Dietary DHA/EPA supplementation ameliorates diabetic nephropathy by protecting from distal tubular cell damage.

The aim was to explore the influence of experimental diabetes mellitus type 1 (DM1) and potential protective/deleterious effects of different dietary n-6/n-3 PUFA ratios on renal phospholipid composition and pathological changes caused by DM1. Male Wistar rats were injected with 55 mg/kg streptozotocin or citrate buffer (control group). Control (C) and diabetic groups (STZ) were fed with n-6/n-3 ratio of ≈ 7, STZ + N6 with n-6/n-3 ratio ≈ 60 and STZ + DHA with n-6/n-3 ratio of ≈ 1 containing 16% EPA and 19% DHA. Tissues were harvested 30 days after DM1 induction. Blood and kidneys were collected and analysed for phospholipid fatty acid composition, pathohystological changes, ectopic lipid accumulation and expression of VEGF, NF-kB and special AT-rich sequence-binding protein-1 (SATB1). Pathological changes were studied also by using transmission electron microscopy, after immunostaining for VEGF. Substantial changes in renal phospholipid fatty acid composition resulted from DM1 and dietary PUFA manipulation. Extensive vacuolization of distal tubular cells (DTCs) was found in DM1, but it was attenuated in the STZ + DHA group, in which the highest renal NF-kB expression was observed. The ectopic lipid accumulation was observed in proximal tubular cells (PTCs) of all diabetic animals, but it was worsened in the STZ + N6 group. In DM1, we found disturbance of VEGF-transporting vesicular PTCs system, which was substantially worsened in STZ + DHA and STZ + N6. Results have shown that the early phase of DN is characterized with extent damage and vacuolization of DTCs, which could be attenuated by DHA/EPA supplementation. We concluded that dietary fatty acid composition can strongly influence the outcomes of DN.

[Isolation of homogeneous polysaccharide from Poria cocos and effect of its sulfated derivatives on migration of human breast cancer MDA-MB-231 cells].

SATB1 plays a crucial role in the invasion and metastasis of breast cancer,and inhibition of SATB1 expression can effectively control breast cancer metastasis. In this study,homogeneous polysaccharides were isolated from Poria cocos and their sulfated derivatives were prepared to screen out the polysaccharide compositions with inhibitory effects on SATB1 expression. Smal-molecule components were removed from P. cocos by ethanol extraction,and P. cocos crude polysaccharide PPS was obtained by water extraction and ethanol precipitation. Then PPS was successively separated by DEAE Sepharose fast flow anion-exchange and Superdex-75 gel permeation chromatographic steps to give PPSW-1. The structure of PPSW-1 was identified and its sulfated derivatives were prepared. Then their inhibitory effects on human breast cancer MDA-MB-231 cells were investigated. A kind of polysaccharide,PPSW-1 with inhibitory effect on human breast cancer MDA-MB-231 cells,was obtained from P. cocos,with a relative molecular weight of 3. 06×104,and structure of 1,6-branched 1,3-α-D-galactan. PPSW-1 and its sulfated derivative Sul-W-1 showed good inhibitory effect on cells migration,and the water solubility of Sul-W-1 was better than that of PPSW-1. In addition,it was found that polysaccharide of P. cocos and its sulfated derivative can inhibit expression of SATB1. In this study,a kind of homogeneous polysaccharide with inhibitory effect on human breast cancer MDA-MB-231 cells was isolated from P. cocos,and its sulfated derivative with similar efficacy but better solubility was prepared,laying the foundation for the substance basis study of P. cocos.

Baicalein suppresses metastasis of breast cancer cells by inhibiting EMT via downregulation of SATB1 and Wnt/ß-catenin pathway.

BACKGROUND: The flavonoid baicalein, a historically used Chinese herbal medicine, shows a wide range of biological and pharmaceutical effects, among which its potent antitumor activity has raised great interest in recent years. However, the molecular mechanism involved in the antimetastatic effect of baicalein remains poorly understood. This study aimed to verify the inhibitory effects of baicalein on metastasis of MDA-MB-231 human breast cancer cells both in vitro and in vivo, as well as to investigate the related mechanisms. METHODS: MTT assay was used to examine the inhibition of baicalein on proliferation of MDA-MB-231 cells. Wound healing assay and the in vitro invasion assay was carried out to investigate the effects of baicalein on migration and invasion of MDA-MB-231 cells, respectively. In order to explore the effects of baicalein on tumor metastasis in vivo, xenograft nude mouse model of MDA-MB-231 cells was established. Animals were randomly divided into four groups (control, therapy group, and low-dose and high-dose prevention group, n=6), and treated with baicalein as designed. Following sacrifice, their lungs and livers were collected to examine the presence of metastases. qRT-PCR and Western blot were performed to study the effects of baicalein on expression of SATB1, EMT-related molecules, and Wnt/ß-catenin signaling components of MDA-MB-231 cells as well as the metastatic tissue. Effects of baicalein on the expression of target proteins in vivo were also analyzed by immunohistochemistry. RESULTS: Our results indicated that baicalein suppressed proliferation, migration, and invasion of MDA-MB-231 cells in a time- and dose-dependent manner. Based on assays carried out in xenograft nude mouse model, we found that baicalein inhibited tumor metastasis in vivo. Furthermore, baicalein significantly decreased the expression of SATB1 in MDA-MB-231 cells. It suppressed the expression of vimentin and SNAIL while enhancing the expression of E-cadherin. Baicalein also downregulated the expression of Wnt1 and ß-catenin proteins and transcription level of Wnt/ß-catenin-targeted genes. CONCLUSION: Our results demonstrate that baicalein has the potential to suppress breast cancer metastasis, possibly by inhibition of EMT, which may be attributed to downregulation of both SATB1 and the Wnt/ß-catenin pathway. Taken together, baicalein may serve as a promising drug for metastasis treatment of breast cancer.

Latest research progress in the correlation between baicalein and breast cancer invasion and metastasis.

Breast cancer is one of the most commonly occurring female malignant tumors. According to the 2012 GLOBOCAN statistics, produced by the International Agency for Research On Cancer ('IARC'), nearly 1.7 million women were diagnosed with breast cancer, with 522,000 related deaths: An increase in the incidence of breast cancer and associated mortality by nearly 18% from 2008. Metastasis is the final step in breast cancer progression, and represents the most common cause of mortality in patients with breast cancer. Therefore, a search for low-toxicity, safe and effective anti-breast cancer drugs in the form of natural compounds has become an intense focus of research. Baicalein, a widely used Chinese herbal medicine, has extensive antitumor activity. The present review briefly describes the research that has been performed on the association between baicalein and breast cancer metastasis, and further illustrates the influence of baicalein on the underlying mechanisms of breast cancer metastasis, adding a novel theory basis for baicalein antitumor research. In conclusion, baicalein may represent a promising target for the prevention and therapy of breast cancer.

Regulation of the MIR155 host gene in physiological and pathological processes.

MicroRNAs (miRNAs), a family of small nonprotein-coding RNAs, play a critical role in posttranscriptional gene regulation by acting as adaptors for the miRNA-induced silencing complex to inhibit gene expression by targeting mRNAs for translational repression and/or cleavage. miR-155-5p and miR-155-3p are processed from the B-cell Integration Cluster (BIC) gene (now designated, MIR155 host gene or MIR155HG). MiR-155-5p is highly expressed in both activated B- and T-cells and in monocytes/macrophages. MiR-155-5p is one of the best characterized miRNAs and recent data indicate that miR-155-5p plays a critical role in various physiological and pathological processes such as hematopoietic lineage differentiation, immunity, inflammation, viral infections, cancer, cardiovascular disease, and Down syndrome. In this review we summarize the mechanisms by which MIR155HG expression can be regulated. Given that the pathologies mediated by miR-155-5p result from the over-expression of this miRNA it may be possible to therapeutically attenuate miR-155-5p levels in the treatment of several pathological processes.