Clinical application of a fixed reference line in the ultrasound quantitative diagnosis of female pelvic organ prolapse.

OBJECTIVE: This study explored using an improved ultrasound (US) for quantitative evaluation of the degree of pelvic organ prolapse(POP). DESIGN: A transluminal probe was used to standardize ultrasound imaging of pelvic floor organ displacements. A US reference line was fixed between the lower edge of the pubic symphysis and the central axis of the pubic symphysis at a 30°counterclockwise angle. METHOD: Points Aa, Ba, C and Bp on pelvic organ prolapse quantification (POP-Q) were then compared with the points on pelvic floor ultrasound (PFUS). RESULTS: One hundred thirteen patients were included in the analysis of the standard US plane. Correlations were good in the anterior and middle compartments (PBN:Aa, ICC = 0.922; PBB:Ba, ICC = 0.923; and PC:C, ICC = 0.925), and Bland-Altman statistical maps corresponding to the average difference around the 30°horizontal line were close to 0. Correlations were poor in the posterior compartment (PRA:Bp, ICC = 0.444). However, eight (7.1%) cases of intestinal hernia and 21 (18.6%) cases of rectocele were diagnosed. CONCLUSIONS: Introital PFUS using an intracavitary probe, which is gently placed at the introitus of the urethra and the vagina, may be accurately used to evaluate organ displacement. The application of a 30°horizontal line may improve the repeatability of the US diagnosis of POP.

Efficacy and safety of high-dose intramuscular vitamin D2 injection in type 2 diabetes mellitus with distal symmetric polyneuropathy combined with vitamin D insufficiency: study protocol for a multicenter, randomized, double-blinded, and placebo-controlled trial.

Background: Distal symmetric polyneuropathy (DSPN) is the most common chronic complication of type 2 diabetes mellitus (T2DM). DSPN may lead to more serious complications, such as diabetic foot ulcer, amputation, and reduced life expectancy. Observational studies have suggested that vitamin D deficiency may be associated with the development of DSPN in T2DM. However, interventional studies have found that low-dose vitamin D supplementation does not significantly improve neuropathy in DSPN. This study aims to evaluate the efficacy and safety of intramuscular injection of high-dose vitamin D (HDVD) in T2DM with DSPN combined with vitamin D insufficiency. Methods and analysis: We will conduct a multicenter, randomized, double-blinded, and placebo-controlled trial in four large hospitals. All eligible participants will be randomly assigned to either the vitamin D2 supplement or placebo control group and injected intramuscularly monthly for 3 months. Additionally, anthropometric measurements and clinical data will be collected at baseline and 3 months. Adverse events will be collected at 1, 2, and 3 months. The primary outcome measure is the change in the mean Michigan Neuropathy Screening Instrument (MNSI) score at baseline and 3 months post-intervention. We will use the gold-standard liquid chromatography-tandem mass spectrometry method to distinguish between 25(OH)D2 and 25(OH)D3 levels. The MNSN score before the intervention will be used as a covariate to compare the changes between both groups before and after the intervention, and the analysis of covariance will be used to analyze the change in the MNSI score after HDVD supplementation. Discussion: Glycemic control alone does not prevent the progression of DSPN in T2DM. Some studies have suggested that vitamin D may improve DSPN; however, the exact dose, method, and duration of vitamin D supplementation are unknown. Additionally, neuropathy repair requires HDVD supplementation to sustain adequate vitamin D levels. This once-a-month intramuscular method avoids daily medication; therefore, compliance is high. This study will be the first randomized controlled trial in China to analyze the efficacy and safety of HDVD supplementation for patients with T2DM and DSPN and will provide new ideas for pharmacological research and clinical treatment of diabetic neuropathy. Clinical trial registration: https://www.chictr.org.cn/, identifier ChiCTR2200062266.

[Maternal neutrophil-to-lymphocyte ratio as a prognostic biomarker for placental inflammatory response in late pregnancy].

OBJECTIVE: To investigate the association between maternal serum neutrophil-lymphocyte ratio (NLR) and placental inflammatory response (PIR) in late pregnancy. METHODS: We retrospectively analyzed the clinical and follow-up data of 478 pregnant women undergoing routine prenatal examination and delivery in our hospital in the year 2016. According to the placental pathological results, the women were divided into PIR group (238 cases) and control group (240 cases). The levels of serum inflammatory makers including leukocytes, neutrophils, lymphocytes, C-reactive protein (CRP) and NLR were compared between the two groups to analyze the association of these markers with PIR. Multivariate analysis was performed to identify the independent risk factors of PIR. Logistic regression model was established and the area under the receiver operating characteristic curve (ROC) was used for analyzing the prognostic value of these makers in late pregnancy. RESULTS: The areas under the curve (AUC) of leukocytes, neutrophils, lymphocytes, CRP and NLR were 0.698 (95%CI: 0.485-0.766), 0.716 (95%CI: 0.453-0.783), 0.329 (95%CI: 0.228-0.431), 0.725 (95%CI: 0.677-0.765) and 0.801 (95%CI: 0.742-0.856), respectively. After adjusting the confounders, multivariate logistic regression analysis showed that preterm labor (OR=2.446, 95%CI: 1.003-4.590), premature rupture of membranes (OR=2.304, 95%CI: 1.049-4.161), NLR > 7 (OR=3.268, 95%CI: 2.071-6.920), and CRP > 15 mg/L (OR=2.137, 95%CI: 1.412-8.236) were independent risk factors for PIR. CONCLUSIONS: An increased NLR in late pregnancy can serve as an effective indicator for predicting the risk of PIR.

[Clinical value of genome-wide chromosome microarray technique in diagnosis of fetal cerebral ventriculomegaly].

OBJECTIVE: To investigate the clinical value of gnome-wide chromosome microarray (CMA) technique in genetic etiological diagnosis of fetal cerebral ventriculomegaly. METHODS: A retrospective analysis was conducted in 109 women with singleton pregnancy, who were admitted in Nanfang Hospital with the diagnosis of cerebral ventriculomegaly in the fetuses by ultrasound between January, 2014 and December, 2016. Routine karyotype analysis and chromosome microarray analysis were performed to identify the chromosomal abnormalities in the fetuses. RESULTS: Karyotype analysis detected chromosomal abnormalities at a rate of 12.84% in these fetuses, significantly lower than the rate of 26.60% with CMA technique (P=0.004); the combined detection rate of the two techniques was 28.44%. In 17 cases, karyotype analysis yielded normal results while CMA microarray showed abnormalities with an extra abnormal detection rate of 15.60%. Among the 17 fetuses with chromosomal abnormalities, 6 had micro-deletion, 9 had micro-duplication, 1 had both micro-deletion and micro-duplication, and 1 had heterozygous loss of single parent diploid. CONCLUSION: CMA technique can be used to detect abnormal chromosomal copy numbers in fetuses with cerebral ventriculomegaly to increase the detection rate of chromosomal abnormalities and facilitate prenatal consultation and prognostic evaluation.

[Correlation analysis of fetal middle cerebral artery peak systolic velocity, cardiothoracic ratio and crown-rump length in early pregnancy].

OBJECTIVE: To explore the pattern of variations in middle cerebral artery peak systolic velocity (MCA PSV) and cardiothoracic ratio (CTR) during early pregnancy, establish their reference ranges and explore their correlation with the crown-rump length (CRL). METHODS: A total of 522 pregnant women with normal findings in antenatal examinations underwent routine color Doppler ultrasound examination to collect the data of MCA PSV, CTR and CRL. The reference ranges of MCA PSV and CTR for different CRL levels were established, and the correlation of MCA PSV and CTR with CRL was analyzed. RESULTS: During the first trimester, MCA PSV and CRL showed a moderate positive correlation with a correlation coefficient of 0.426 (P<0.001), while CTR and CRL showed no significant correlation (0.168, P<0.001). The reference range of MCA PSV was 14.35 (14.08-14.62) cm/s and that of CTR was 0.34 (0.33-0.34) during early pregnancy. CONCLUSION: Color Doppler ultrasound is a safe and feasible modality to assess fetal MCA PSV and CTR for detecting fetal growth abnormalities in early pregnancy. The established reference ranges of MCA PSV and CTR offer a clinical theoretical basis for detecting α-thalassemia in early pregnancy.

Tanshinone IIA protects against acetaminophen-induced hepatotoxicity via activating the Nrf2 pathway.

BACKGROUND: Tanshinone IIA (Tan), the main active component of Salvia miltiorrhiza, has been demonstrated to have antioxidant activity. Acetaminophen (APAP), a widely used antipyretic and analgesic, can cause severe hepatotoxicity and liver failure when taken overdose. Oxidative stress has been reported to be involved in APAP-induced liver failure. PURPOSE: This study aimed to investigate the effect of Tan on APAP-induced hepatotoxicity and the underlying mechanisms involved. STUDY DESIGN: C57BL/6J mice were divided into six groups: (1) control, (2) APAP group, (3) APAP+Tan (30mg/kg) group, (4) Tan (30mg/kg) group, (5) APAP+Tan (10mg/kg) group, (6) Tan (10mg/kg) group. Mice in group 3 and 5 were pre-treated with specified dose of Tan by gavage and subsequently injected with an overdose of APAP intraperitoneally (i.p., 300mg/kg). The effect of Tan on Nrf2 pathway was investigated in HepG2 cells and mice. METHODS: Plasma aspartate transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), liver glutathione (GSH), glutathione transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) levels were determined after mice were sacrificed. Lipid peroxidation and histological examination were performed. The effect of Tan on the Nrf2 pathway was detected by western blotting and qRT-PCR. RESULTS: Tan pretreatment reduced APAP-induced liver injury. Tan was able to activate Nrf2 and increase the expression levels of Nrf2 target genes, including glutamate-cysteine ligase catalytic subunit (GCLC), NAD(P)H:quinine oxidoreductase 1 (NQO1) and hemeoxygenase-1 (HO-1), in a dose-dependent manner in HepG2 cells. Consistent with our observations in HepG2 cells, Tan increased nuclear Nrf2 accumulation and upregulated mRNA and protein levels of the Nrf2 target genes GCLC, NQO1 and HO-1 in C57BL/6J mice compared with mice treated with APAP alone. CONCLUSIONS: Our results demonstrate that Tan pretreatment could protect the liver from APAP-induced hepatic injury by activating the Nrf2 pathway. Tan may provide a new strategy for the protection against APAP-induced liver injury.

Activation of SIRT3 attenuates triptolide-induced toxicity through closing mitochondrial permeability transition pore in cardiomyocytes.

Triptolide (TP), an active component of the traditional Chinese herb Tripterygium wilfordii Hook f. (TWHF), has multiple pharmacological effects. However, the severe toxicity of TP greatly restricts its clinical applications. Although TP exposure causes serious heart injury, the mechanism underlying TP-induced cardiotoxicity has rarely been investigated. In previous studies, we found that TP-induced oxidative stress was involved in the mitochondria-dependent apoptosis of cardiomyocytes. Opening of the mitochondrial permeability transition pore (mPTP) is the key to the mitochondrial dysfunction in cardiac toxicity. The aim of this study was to investigate the potential cardioprotective effects of sirtuin 3 (SIRT3) on the mPTP. In the present study, the cytotoxicity of TP was accompanied by the up-regulation of the SIRT3 protein level and its rapid aggregation in nuclei and mitochondria. The SIRT3-FOXO3 signaling pathway was activated simultaneously, resulting in increased transcription of manganese superoxide dismutase (MnSOD) and catalase (CAT) for the elimination of reactive oxygen species (ROS). In addition, augmentation of the SIRT3 level via the overexpression plasmid SIRT3-Flag provided resistance to TP-induced cellular damage, whereas knocking down the SIRT3 level via siRNA accelerated the damage. Because it is an activator of SIRT3, the protective effect of resveratrol was also evaluated in H9c2 cells. In conclusion, the current results suggest that activation of SIRT3 substantially ameliorates the detrimental effects of TP by closing the mPTP.

Giganteaside D induces ROS-mediated apoptosis in human hepatocellular carcinoma cells through the MAPK pathway.

PURPOSE: Every year, almost one million individuals are diagnosed with hepatocellular carcinoma (HCC) worldwide and more than 690,000 patients die of it. At present, most therapeutic anti-HCC agents are not effective, which is due to the appearance of chemo-resistance and/or toxic side effects. Therefore, it is imperative to find novel more effective anti-HCC agents. Here, we evaluated the effect of giganteaside D (GD), an oleanolic acid saponin from P. scabiosaefolia, on the growth and apoptosis of HCC cells. METHODS AND RESULTS: Using MTT and clonogenic assays, we found that GD exhibited a significant growth inhibitory effect on the HCC-derived cell lines HepG2 and Bel-7402. In addition, we found that GD induced mitochondria-mediated apoptosis in these HCC-derived cells, as indicated by a decreased mitochondrial potential, activation of Caspase-9 and Caspase-3, cleavage of PARP and release of Cytochrome C from the mitochondria. Besides, we found that GD stimulated the generation of reactive oxygen species (ROS) and that blockage of ROS attenuated the GD-induced mitochondria-mediated apoptosis. Additionally, we found that GD treatment led to a decrease in phosphorylated Erk (p-Erk) and triggered the generation of p-JNK, both components of the mitogen-activated protein kinase (MAPK) signaling pathway. Inhibition of Erk or JNK by specific inhibitors or siRNAs augmented or attenuated the cytotoxic and apoptotic effects of GD. CONCLUSIONS: From our results we conclude that GD can induce ROS-mediated apoptosis in HCC-derived cells through the MAPK pathway. This observation may open up avenues to explore the future use of GD as a HCC chemotherapeutic agent.

Resveratrol protects against triptolide-induced cardiotoxicity through SIRT3 signaling pathway in vivo and in vitro.

Clinical application of triptolide (TP), a main active ingredient of the traditional Chinese herb Tripterygium wilfordii Hook f. (TWHF), is limited by a series of severe toxicities, including cardiotoxicity. In previous studies, we found the activation of sirtuin 3 (SIRT3) attenuated TP-induced toxicity in cardiomyocytes. Resveratrol (RSV), a polyphenol from the skins of grapes and red wine, is an activator of SIRT3. The current study aimed to investigate the protective effect of RSV against TP-induced cardiotoxicity and the underlying mechanisms. Mice were treated with a single dose of TP (2.5 mg/kg) via the intragastric (i.g.) route. After 24 h, TP induced abnormal changes of serum biochemistry, activity decrease of antioxidant enzymes and damage of heart tissue such as myocardial fiber rupture, cell swelling and interstitial congestion. In contrast, administration with RSV (50 mg/kg i.g. 12 h before and 2 h after the administration of TP) attenuated the detrimental effects induced by TP in BALB/c mice. Moreover, the cardiomyocyte protective effects of RSV on TP-induced heart injury were associated with the activation of SIRT3 and its downstream targets. In vitro study also indicated that RSV counteracted TP-induced cardiotoxicity through SIRT3-FOXO3 signaling pathway in H9c2 cells. Collectively, these findings suggest the potential of RSV as a promising agent in protecting heart from TP-induced damage.

[Effects of Litchi chinensis Seed Saponins on Inhibiting Hyperplasia of Mammary Glands and Influence on Signaling Pathway of Estrogen in Rats].

OBJECTIVE: To discuss the role of Litchi chinensis seed saponins on hyperplasia of mammary glands(HMG) and the influence of estrogen signaling pathways in rats. METHODS: In addition to eight non-pregnant female SD rats in normal control group, the other 32 pathologic models of HMG rat model were randomly divided into other four groups: model control group, low and high dose groups, which were given experimental drug of Litchi chinensis seed saponins (LSE) 0. 1 g/kg and 0. 2 g/kg, and the positive control group with experimental drug of tamoxifen 4 mg/kg. Then all model rats were orally administrated for four weeks. The diameter and height of nipple were measured, and the content changes of estradiol(E2) and progestrogen(P) in serum were detected with ELISA method. The HMG were detected by the morphology examination. The expression of estrogen receptor(ER) and progesterone receptor(PR) in the mammary glands were investigated by immunohistochemical staining. RESULTS: According to LSE in the low and high dose groups, it was discovered that the nipple diameter and height of HMG rats, the expression of ER and PR in HMG and the content of serum E2 were reduced, the content of serum P were improved, and the hyperplasia of mammary glands was inhibited. CONCLUSION: LSE can obviously inhibit the rat hyperplasia of mammary gland, and its possible mechanism is related to adjusting the transduction pathway of estrogen signal to lower estrogen levels.

Activation of the farnesoid X receptor attenuates triptolide-induced liver toxicity.

BACKGROUND: Triptolide, an active ingredient extracted from the Chinese herb Tripterygium wilfordii Hook f., has multiple pharmacological properties, including anti-inflammatory, immune-modulatory, and anti-proliferative activities. However, the hepatotoxicity of triptolide always limits its clinical applications. HYPOTHESIS/PURPOSE: Farnesoid X receptor (FXR) is a ligand-activated transcription factor that plays a key role in hepatoprotection through the maintenance of liver metabolism homeostasis. This study explored the role of FXR in triptolide-induced cytotoxicity and investigated whether activation of FXR can protect against triptolide-induced liver injury. STUDY DESIGN: The role of FXR in triptolide-induced cytotoxicity was investigated in HepG2 cells. In addition, the protective effect of the selective FXR agonist GW4064 on triptolide-induced hepatotoxicity was explored in BALB/c mice. METHODS: HepG2 cells were transient transfected with FXR expression plasmid or FXR-siRNA. The cytotoxicity was compared using the MTT assay. The extent of liver injury was assessed by histopathology and serum aminotransferases. The expression of FXR and its target genes were detected by Western blot and qRT-PCR. RESULTS: The transient overexpression of FXR protected against triptolide-induced cell death, whereas FXR knockdown with a specific small interfering RNA resulted in increased cytotoxicity. In BALB/c mice, treatment with the FXR agonist GW4064 attenuated triptolide-induced liver dysfunction, structural damage, glutathione depletion and lipid peroxidation. Moreover, the livers of GW4064-treated mice showed increased expression of FXR and several related target genes involved in phase II and phase III xenobiotic metabolism. CONCLUSION: Taken together, these results indicate that activation of FXR attenuates triptolide-induced hepatotoxicity and provide direct implications for the development of novel therapeutic strategies against triptolide-induced hepatotoxicity.

Autophagy plays an important role in triptolide-induced apoptosis in cardiomyocytes.

Triptolide (TP), a major bioactive component isolated from the traditional Chinese herb Tripterygium wilfordii Hook f. (TWHF), has been shown to exert various pharmacological effects. However, the severe toxicity of TP prevents wide clinical use. In a previous study, we reported that TP-induced mitochondria-dependent apoptosis in cardiomyocytes is mediated by reactive oxygen species (ROS). Autophagy is a cellular self-digestion process and is one of the first lines of defense against oxidative stress. Additionally, recent evidence suggests that autophagy can selectively eliminate damaged mitochondria. This study investigated the role of autophagy in TP-induced cardiotoxicity. We investigated the effects of autophagy in combination with TP on apoptosis, ROS and mitochondrial function. Rat cardiomyocytes were pre-treated with chloroquine or rapamycin followed by TP. The augmentation of autophagy with rapamycin in the presence of TP substantially ameliorated the detrimental effects induced by TP, while suppression of autophagy by chloroquine accelerates TP-induced cellular damage. In addition, pre-treated with rapamycin before TP administration also attenuated TP-induced damage in Balb/c mice heart tissues. Taken together, these results suggest that TP-induced cell death can be modified by autophagy. Furthermore, induction of autophagy by rapamycin may be a potential cardioprotective role against TP-induced cardiotoxicity by facilitating removal of dysfunctional mitochondria.

Triptolide-induced oxidative stress involved with Nrf2 contribute to cardiomyocyte apoptosis through mitochondrial dependent pathways.

Triptolide (TP), a major active ingredient extracted from the widely used Chinese herb Tripterygium wilfordii Hook f. (TWHF), has been demonstrated to possess various biological activities. However, the clinical applications of TP are limited by its narrow therapeutic window and severe toxicity. The current study aimed to investigate the roles of reactive oxygen species (ROS) and mitochondria in TP-induced cardiac injury. Male BALB/C mice were intravenously (i.v.) treated with a single dose of TP (1.2 mg/kg). After 24h, TP induced the oxidative stress, mitochondrial dysfunction, apoptotic damage, and pathological changes of heart tissue. In vitro studies also indicated that the cytotoxic effects of TP involved the ROS-mediated mitochondria-dependent pathway in H9c2 cells. TP treatment increased the accumulation of ROS and subsequently triggered cell apoptosis by depolarizing the mitochondrial membrane potential (ΔΨm), reduced the ratio of Bax/Bcl-2, released cytochrome c and, ultimately, activated caspase-3. Nrf2, as well as its downstream antioxidants, were also suppressed by TP. Taken together, these results suggest that TP induces cardiotoxicity in vivo and in vitro via oxidative stress, which was associated with down regulated Nrf2 activation, and the mitochondria-mediated apoptotic signaling pathway.

ZNF217 is associated with poor prognosis and enhances proliferation and metastasis in ovarian cancer.

ZNF217 is an alternatively spliced Kruppel-like transcription factor that has recently been implicated to play a role in human carcinogenesis. Here, we used immunohistochemistry (IHC) to show that ZNF217 protein is overexpressed in nearly 60% of ovarian tumor samples. The disease-free survival time was shorter in patients with positive ZNF217 expression than in ZNF217-negative patients (P=0.042). Fluorescence in situ hybridization (FISH) analysis showed ZNF217 genomic amplification in the poorly differentiated tumors, suggesting that ZNF217 is associated with the progression of ovarian cancer. Invasion was enhanced in HO-8910 cells stably transfected with constructs carrying full-length ZNF217 relative to cells transfected with the empty vector. To confirm our findings in vivo, we performed a tumorigenicity assay in nude mice inoculated with the HO-8910 overexpressing ZNF217 cells. As expected, tumors grown in the ZNF217 group were more invasive and prone to metastasis than those formed control groups. Based on these clinical and laboratory observations, we conclude that ZNF217 may contribute to ovarian cancer invasion and metastasis, and associated with worse clinical outcomes.

The developmental pattern of the RAS/RAF/Erk1/2 pathway in the BTBR autism mouse model.

BTBR mice exhibit several autistic-like behaviors and are currently used as a model for understanding mechanisms that may be responsible for the pathogenesis of autism. Ras/Raf/ERK1/2 signaling has been suggested to play an important role in neural development, learning, memory, and cognition. Two studies reported that a deletion of a locus on chromosome 16 containing the mitogen-activated protein kinase 3 (MAPK3) gene, which encodes ERK1, is associated with autism. In the present study, Ras/Raf/ERK1/2 signaling was found to be up-regulated in BTBR mice relative to matched control B6 mice, to further suggest involvement in the pathogenesis of autism. To further characterize the developmental pattern of Ras/Raf/ERK1/2 signaling, varying stages during development were sampled to reveal an up-regulation in newborn and 2-week old BTBR mice relative to age-matched B6 mice. By the age of 3-week, Ras/Raf/ERK1/2 signaling in the brain of BTBR mice was unaltered relative to B6 mice, with this trend maintained in 6-week samples. These results suggest that the alteration of Ras/Raf/ERK signaling in the early developmental stages in mice could contribute to the noted autistic phenotype. Furthermore, these findings support the value of BTBR mice to serve as a human analog for autistic etiological research and aid in a better understanding of the developmental mechanisms of autism.

[Prenatal diagnosis of single umbilical artery: implications for chromosomal abnormalities and neonatal outcome].

OBJECTIVE: To investigate the implications of a prenatal diagnosis of single umbilical artery (SUA) for chromosomal abnormalities and neonatal outcomes. METHODS: From January, 2008 to June, 2012, color Doppler ultrasound identified 44 fetuses with SUA. Prenatal diagnoses with amniocentesis or umbilical blood sampling were subsequently ordered for routine chromosome karyotyping and the newborns were followed up for assessing the neonatal outcomes. RESULTS: Of all the 44 fetuses, 24 had uncomplicated SUA, and 20 had other concurrent abnormalities (including 8 with abnormal ultrasound soft indexes and 12 with chromosomal abnormalities). The two groups of fetuses showed significant differences in gestational weeks at delivery and incidence of chromosomal abnormalities but not in neonatal weight, placenta weight or APGAR score. CONCLUSIONS: Fetuses with a prenatal diagnosis of SUA and other development abnormities need to undergo prenatal chromosomal examination. For fetuses with uncomplicated SUA, careful ultrasound examination is necessary to avoid missed diagnosis of potential congenital abnormalities.

Necroptosis contributes to the cyclosporin A-induced cytotoxicity in NRK-52E cells.

Cyclosporin A (CsA) induces renal tubular epithelial cells apoptosis and necrosis following in vitro exposure. The mechanisms of CsA-induced apoptosis have been studied intensively, whereas the mechanisms of necrosis remain to be elucidated. Necroptosis has been described as programmed necrosis. This study investigated the ability of CsA to induce necroptosis in the rat tubular cell line NRK-52E. The NRK-52E cells were incubated with CsA for 24 hours with or without necrostatin-1 (Nec-1). The majority of the NRK-52E cells died of necrosis as indicated by LDH leakage, Hoechst 33342/PI staining, and flow cytometry analysis. Cell death was significantly reduced by Nec-1 pretreated before CsA exposure. CsA-induced apoptosis and necrosis were also compared in NRK-52E cells with or without knockdown of receptor interaction protein 3 (RIP3) expression using small interfering RNA. Moreover, the role of reactive oxygen species (ROS) in CsA-induced cell death was also attempted. The result suggests that necroptosis contributes to the CsA-induced cytotoxicity in NRK-52E cells. Meanwhile, RIP3 and ROS are involved in CsA-induced necroptosis. To our knowledge, this is the first report on necroptosis in CsA-induced renal tubular cell death pathways, which might offer a novel protective target for CsA nephrotoxicity.

Role of Nrf2 in protection against triptolide-induced toxicity in rat kidney cells.

Triptolide is a major active ingredient of the Chinese herb Tripterygium wilfordii Hook f. (TWHF) and has been shown to possess multiple biological activities, such as anti-inflammatory, anti-fertility, anti-neoplastic and immunosuppressive activities. However, severe adverse effects, especially nephrotoxicity, limit its clinical use. Oxidative stress has been reported to be involved in triptolide-induced renal injury, but the existence of other mechanisms remains unclear. This study aimed to investigate whether NF-E2-related factor 2 (Nrf2), which is an antioxidant nuclear transcription factor, plays a protective role in defense against triptolide-induced toxicity in a normal rat kidney cell line (NRK-52E). Triptolide induced oxidative stress in NRK-52E cells by induction of reactive oxygen species (ROS) and depletion of glutathione (GSH), which resulted in a rapid increase in Nrf2 nuclear accumulation, as well as an induction of antioxidant response element (ARE)-driven genes. In addition, overexpression of Nrf2 protected against triptolide-induced cell death, whereas knockdown of Nrf2 by its specific small interfering RNA resulted in increased cytotoxicity. We also found that Nrf2 knockdown enhanced both the production of ROS and the depletion of GSH. Taken together, these results indicate that activation of Nrf2 plays a protective role against triptolide-induced cytotoxicity in NRK-52E cells through the counteraction of oxidative stress.

Protective effect of schisandrin B against cyclosporine A-induced nephrotoxicity in vitro and in vivo.

Schisandrin B (Sch B) is an active ingredient of the fruit of Schisandra chinensis. It has many therapeutic effects arising from its tonic, sedative, antitussive and antiaging activities and is also used in the treatment of viral and chemical hepatitis. The aim of this study was to investigate the protective effects of Sch B on cyclosporine A (CsA)-induced nephrotoxicity in mice and HK-2 cells (a human proximal tubular epithelial cell line). After gavage with Sch B (20 mg/kg) or olive oil (vehicle), mice received CsA (30 mg/kg) by subcutaneous injection once daily for four weeks. Renal function, histopathology, and tissue glutathione (GSH) and malondialdehyde (MDA) levels were evaluated after the last treatment. The effects of Sch B on CsA-induced oxidative damage in HK-2 cells were investigated by measuring cell viability, the release of lactate dehydrogenase (LDH), the level of reactive oxygen species (ROS), and the cellular GSH and ATP concentrations. Cellular apoptosis was assessed by flow cytometry. Treatment with Sch B in CsA-treated mice significantly suppressed the elevation of blood urea nitrogen (BUN) and serum creatinine levels and attenuated the histopathological changes. Additionally, Sch B also decreased renal MDA levels and increased GSH levels in CsA-treated mice. Using an in vitro model, Sch B (2.5, 5 and 10 µM) significantly increased the cell viability and reduced LDH release and apoptosis induced by CsA (10 µM) in HK-2 cells. Furthermore, Sch B increased the intracellular GSH and ATP levels and attenuated CsA-induced ROS generation. In conclusion, Sch B appears to protect against CsA-induced nephrotoxicity by decreasing oxidative stress and cell death.

Endoplasmic reticulum stress mediates aristolochic acid I-induced apoptosis in human renal proximal tubular epithelial cells.

Aristolochic acid (AA), derived from the Aristolochia species, has been associated with aristolochic acid nephropathy (AAN), which has emerged as a worldwide disease. Aristolochic acid I (AAI) is the main ingredient of AA, and the underlying mechanisms for AAI-induced nephrotoxicity are still unclear. In this study, we investigated whether endoplasmic reticulum (ER) stress was involved in AAI-induced nephrotoxicity. The results showed that treatment of HK-2 cells (a human proximal tubular epithelial cell line) with AAI caused an increase in eukaryotic initiation factor-2α (eIF2α) phosphorylation, X-box binding protein 1 (XBP1) mRNA splicing and the expression of glucose-regulated protein (GRP) 78 and CAAT/enhancer-binding protein-homologous protein (CHOP). These events represent typical markers of the ER stress-related signaling pathway. Pretreatment with 4-phenylbutyrate (4-PBA) or salubrinal (Sal) significantly inhibited AAI-induced apoptosis, indicating the role of ER stress in AAI-induced apoptosis. In addition, AAI-induced cell death followed an increase of reactive oxygen species (ROS) formation in HK-2 cells. Pretreatment with N-acetyl cysteine (NAC) or glutathione (GSH) significantly inhibited AAI-induced ER stress proteins and cell death, suggesting that ROS mediate AAI-induced ER stress. Taken together, these results suggest that the ER stress response is involved in apoptosis induced by AAI in HK-2 cells, thus offering a new insight into the nephrotoxicity of AAI.