Protective Effects of Total Flavonoids from Lysimachia christinae on Calcium Oxalate-Induced Oxidative Stress in a Renal Cell Line and Renal Tissue

Oxidative stress (OS) in renal tubular epithelial cells (RTECs) is induced by calcium oxalate (CaOx) stones and plays an important role in the pathology of CaOx nephrolithiasis. The nuclear factor-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway is an important endogenous antioxidant pathway. Flavonoids are compounds with 2-phenylchromone as the basic mother nucleus and are natural antioxidant components of Lysimachia christinae. Our previous studies demonstrated that the total flavonoids from L. christinae (TFL) reduced calcium and oxalic acid concentrations in urine, thus inhibiting CaOx stone formation. We also showed that TFL can reduce OS in renal tissue. However, whether TFL inhibit the formation of CaOx stones through the Nrf2/ARE pathway requires further investigation. Here, we found that TFL protected against injury to a renal cell line and renal tissue, reduced CaOx-induced OS in renal tissue, and reduced CaOx crystal formation. In addition, TFL significantly increased nuclear Nrf2 and the expression of the downstream antioxidant genes heme oxygenase 1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO-1). Furthermore, TFL increased superoxide dismutase (SOD) activity and decreased the malondialdehyde (MDA) content, thereby alleviating OS in RTECs. Silencing Nrf2 expression blocked the protective effect of TFL on CaOx-induced OS. Taken together, our findings indicate that TFL reduce CaOx-induced OS in renal tissue by activating the Nrf2/ARE pathway.

Protective Effects of Total Flavonoids from Lysimachia Christinae on Calcium Oxalate-Induced Oxidative Stress in a Renal Cell Line and Renal Tissue

Background: Flavonoids are compounds with 2-phenylchromone as the basic mother nucleus and are natural antioxidant components of Lysimachia christinae. We previously demonstrated that total flavonoids from L. christinae (TFL) reduce calcium and oxalic acid concentrations in urine and can reduce oxidative stress (OS) in renal tissue, thus, inhibiting calcium oxalate (CaOx) stone formation. The aim of this study was to investigate whether TFL reduced OS in renal tissue, thereby inhibiting CaOx stone formation through the nuclear factor-E2 related factor 2 (Nrf2)/antioxidant response element (ARE) pathway.Methods: The rat model of CaOx stone was established by providing rats with drinking water containing 0.5% glycol and 2% ammonium chloride. After 4 weeks of treatment with different doses of TFL (62.5, 125, and 250 mg/kg/d), body and kidney weights of the rats were measured. CaOx crystal formation was observed under the microscope and the renal tissue contents of superoxide dismutase (SOD) and malondialdehyde (MDA) were analyzed. HK-2 cells were divided into two groups: treatment with CaOx crystals or CaOx crystals + TFL. Other HK-2 cells were treated with small interfering RNA targeting nuclear factor-E2 related factor 2 (Nrf2) and divided into the same two groups. The activities of SOD and content of MDA were measured. The expression of Nrf2, heme oxygenase (HO-1), and NAD(P)H quinone oxidoreductase 1 (NQO-1) were detected using western blot.Results: In the in vitro study, TFL significantly increased nuclear Nrf2 and expression of the downstream antioxidant genes, HO-1 and NQO-1. Furthermore, TFL increased superoxide dismutase activity and decreased the malondialdehyde content, thereby alleviating OS in renal tubular epithelial cells. Moreover, silencing the expression of Nrf2 blocked the protective effect of TFL on CaOx-induced OS. In the in vivo study TFL protected the renal cell line and renal tissue against injury, reduced CaOx-induced OS in renal tissue, and reduced CaOx crystal formation.Conclusions: TFL reduces CaOx-induced OS in renal tissue by activating the nuclear Nrf2/antioxidant response element (ARE) pathway.

MiR-411 Functions as a Tumor Suppressor in Renal Cell Cancer

Background Recent studies have revealed that microRNAs (miRNAs) play important roles as oncogenes or tumor suppressors in tumorigenesis and tumor development, by negatively regulating protein expression. A previous study of microarrays identified that miR-411 was down-regulated in renal cell carcinoma (RCC), while few studies investigating the role of miR-411 in the pathogenesis of RCC have been performed. Methods We assessed the miR-411 expression in RCC and paired adjacent normal tissues, as well as in RCC cell lines and a normal renal cell line, by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Furthermore, the effects of miR-411 on RCC and normal renal cell proliferation, apoptosis and migration were determined using MTT assay, CCK-8 assay, flow cytometry and scratch wound assay following restoration of miR-411 with synthetic mimics. Results Results of qRT-PCR indicated that the expression of miR-411 was down-regulated in RCC tissues and cell lines when compared with adjacent normal tissues and a normal renal cell line. Further, results of CCK-8, MTT, cell scratch and transwell assay showed that over-expression of miR-411 suppressed RCC cell (786-0 and ACHN) proliferation and migration. Flow cytometry assay revealed that miR-411 could induce RCC cell apoptosis. However, overexpression of miR-411 had no obvious effect on normal renal cell line 293T Conclusions To sum up, miR-411 is significantly down-regulated and plays a role as a tumor suppressor in RCC. Further studies are warranted to determine the mechanisms of miR-411 in RCC pathogenesis and define the target genes of miR-411 in RCC.

Upregulation of FBXW7 Suppresses Renal Cancer Metastasis and Epithelial Mesenchymal Transition

Background and Objective. FBXW7, known as a general tumor suppressor, is commonly lowly expressed in metastatic malignancies. We aim to investigate the potential influence of FBXW7 overexpression on renal cell carcinoma (RCC) metastasis. Methods. We employed quantitative real-time PCR (qRT-PCR) and Western blotting (WB) to quantify the FBXW7 expression in RCC cell lines. Upregulation of FBXW7 was performed in vitro on RCC cells using the lentivirus covering coding region FBXW7 cDNA sequence, and functional tests were performed to verify FBXW7 overexpression on migration and invasion of RCC cells. Moreover, WB was employed to determine the expressions of MMP-2, MMP-9, and MMP-13, as well as EMT markers in the transfected RCC cells. Results. FBXW7 was significantly downregulated in RCC cell lines, dominated by 786-O and ACHN, when compared to normal renal cell line HK-2. Moreover, upregulation of FBXW7 in 786-O and ACHN cell lines significantly inhibited cell migration and invasion, as well as EMT. Present study also showed that FBXW7 was involved in the migration and invasion of RCC cells via regulating the expressions of MMP-2, MMP-9, and MMP-13. Conclusion. Our findings demonstrate that upregulation of FBXW7 inhibits RCC metastasis and EMT. FBXW7 is a potential therapeutic target for RCC patients.

Different Cytokine and Chemokine Expression Patterns in Malignant Compared to Those in Nonmalignant Renal Cells

Objective. Cytokines and chemokines are widely involved in cancer cell progression and thus represent promising candidate factors for new biomarkers. Methods. Four renal cell cancer (RCC) cell lines (Caki-1, 786-O, RCC4, and A498) and a nonmalignant renal cell line (RC-124) were examined with respect to their proliferation. The cytokine and chemokine expression pattern was examined by a DNA array (Human Cytokines & Chemokines RT2 Profiler PCR Array; Qiagen, Hilden, Germany), and expression profiles were compared. Results. Caki-1 and 786-O cells exhibited significantly increased proliferation rates, whereas RCC4 and A498 cells demonstrated attenuated proliferation, compared to nonmalignant RC-124 cells. Expression analysis revealed 52 cytokines and chemokines primarily involved in proliferation and inflammation and differentially expressed not only in malignant and nonmalignant renal cells but also in the four RCC cell lines. Conclusion. This is the first study examining the expression of 84 cytokines and chemokines in four RCC cell lines compared to that in a nonmalignant renal cell line. VEGFA, NODAL, and BMP6 correlated with RCC cell line proliferation and, thus, may represent putative clinical biomarkers for RCC progression as well as for RCC diagnosis and prognosis.

Monitoring biological effects of 20 nm versus 100 nm silica nanoparticles induced on a human renal cell line using Fourier transform infrared spectroscopy

A method based on FTIR spectroscopy was proposed for monitoring the biological effects induced on human renal cells with SiO2 nanoparticles (NPs).