Bradykinin protects against DDP-induced GP-H1 cell damage via activation of PI3K/Akt/NO signaling pathway.

OBJECTIVE: To investigate the effect of bradykinin (BK) on cisplatin (DDP)-induced cardiotoxicity at the cellular level and its cytological mechanism. METHODS: The toxic effects of DDP on GP-H1 cells, and the effects of BK on DDP cardiomyocyte survival rate, DDP-induced malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), reactive oxygen species (ROS), mitochondria membrane potential (MMP) and apoptosis were explored. RESULTS: DDP at different concentrations inhibited GP-H1 cells at 12 h after administration, and the inhibitory effect was more prominent at 24 h after administration and continued until 72 h after administration. The severity of GP-H1 cell damage induced by DDP was reduced by 0.1 µM, 1 µM, and 10 µM BK. After GP-H1 cells were treated with DDP, ROS levels increased and MMP levels decreased, while BK intervention inhibited these effects. At 24 h after DDP treatment, Bax/bcl-2 increased in GP-H1 cells, and the expressions of Caspase-3, p-NF-κB, p-p38 and p-Smad2 decreased. After intervention with BK, it was shown that Bax/Bcl-2 was significantly reduced, and the expressions of Caspase-3, p-NF-κB, p-p38 and p-Smad2 decreased. Bax/Bcl-2 and the expressions of Caspase-3, p-NF-κB, p-p38 and p-Smad2 of GP-H1 cells were basically not affected by BK alone. CONCLUSION: The protective effect of BK on DDP-induced GP-H1 cell damage in guinea pig is related to the activation of PI3K/Akt/NO signaling pathway by BK, which reduces oxidative stress levels in cardiomyocytes and also acts as an anti-apoptotic agent.

Association between Environmental Dioxin-Related Toxicants Exposure and Adverse Pregnancy Outcome: Systematic Review and Meta-Analysis.

Dioxin-related compounds are associated with teratogenic and mutagenic risks in laboratory animals, and result in adverse pregnancy outcomes. However, there were inconsistent results in epidemiology studies. In view of this difference, we conducted a systematic review and meta-analysis to examine this association and to assess the heterogeneity among studies. Comprehensive literature searches were performed to search for relevant articles published in English up to 15 May 2012. In total, we identified 15 studies which included 9 cohort and 6 case control studies. The Cochrane Q test and index of heterogeneity (I(2)) were used to evaluate heterogeneity. In either cohort studies (I(2)=0.89, p<0.0001) or case control studies (I(2)=0.69, p=0.02), significant heterogeneity of risk estimates were observed. Subgroup analyses found no significant increased risk of adverse pregnancy outcome with air dioxin-related compounds exposure (RR=0.99, 95% CI:0.85-1.16), no significant increased risk of spontaneous abortion (SAB) with exposure to food dioxin-related compounds (RR=1.05, 95% CI:0.80-1.37), higher significant risks of low birth weight (LBW) with exposure to food dioxin-related compounds (RR=1.55, 95% CI:1.24-1.94), and higher significant risks of birth defects with maternal solid contaminants dioxin exposure (OR=1.24, 95% CI:1.19-1.29). In conclusion, more evidences are needed to confirm the association between environmental dioxin-related compounds exposure and pregnancy outcome.

Association between Maternal MTHFR Polymorphisms and Nonsyndromic Cleft Lip with or without Cleft Palate in Offspring, A Meta-Analysis Based on 15 Case-Control Studies.

BACKGROUND: The methylenetetrahydrofolate reductase (MTHFR) is thought to be involved in the development of nonsyndromic cleft lip with or without cleft palate (NSCL/P). However, conflicting results have been obtained when evaluating the association between maternal MTHFR C677T and A1298C polymorphisms and the risk of NSCL/P. In light of this gap, a meta-analysis of all eligible case-control studies was conducted in the present study. MATERIALS AND METHODS: A total of 15 case-control studies were ultimately identified after a comprehensive literature search and Hardy-Weinberg equilibrium (HWE) examination. Cochrane's Q test and index of heterogeneity (I(2)) indicated no obvious heterogeneity among studies. RESULTS: Fixed or random-effects models were used to calculate the pooled odds ratios (ORs). The results showed that the TT genotype in mothers increased the likelihood of having NSCL/P offspring 1.25 times (95% CI: 1.047-1.494) more than the CC homozygotes. Meanwhile, maternal TT genotype increased the risk of producing NSCL/P offspring in recessive model (OR=1.325, 95% CI: 1.124-1.562). However, the CT heterozygote and the CT+TT dominant models had no association with NSCL/P offspring compared with the CC wild-type homozygote model. Subgroup analyses based on ethnicity indicated that maternal TT genotype increased the likelihood of having NSCL/P offspring in Whites (OR=1.308, 95% CI: 1.059-1.617) and Asians (OR=1.726, 95% CI: 1.090-2.733) in recessive model. Also, subgroup analyses based on source of control showed that mothers with the 677TT genotype had a significantly increased susceptibility of having NSCL/P children in hospital based population (HB) when compared with CC homozygotes (OR=1.248, 95% CI: 1.024-1.520) and un- der the recessive model (OR=1.324, 95% CI: 1.104-1.588). Furthermore, maternal A1298C polymorphism had no significant association with producing NSCL/P offspring (dominant model OR=0.952, 95% CI: 0.816-1.111, recessive model OR=0.766, 95% CI: 0.567-1.036). CONCLUSION: MTHFR C677T polymorphism is associated with the risk of generating NSCL/P offspring, and being a 677TT homozygote is a risk factor. MTHFR A1298C polymorphism was not associated with generating NSCL/P offspring. However, further work should be performed to confirm these findings.

Identification and comparative analysis of the major chemical constituents in the extracts of single fuzi herb and fuzi-gancao herb-pair by UFLC-IT-TOF/MS.

AIM: The aim of this work was to establish a specific and sensitive method to comprehensively investigate and compare chemical constituents of Fuzi-Gancao herb pair (FG), consisting of Aconitum carmichaelii Debeaux (Fuzi, Chinese) and Roast Radix Glycyrrhizae (Glycyrrhiza glabra L., Gancao, in Chinese) and Fuzi alone to explore the underlying interaction mechanism of FG. METHOD: An ultra-fast liquid chromatography-ion trap/time-of-flight mass spectrometry (UFLC/MS-IT-TOF) method using diazepam as internal standard was developed for the identification and semi-quantitative analysis of the phytochemical constituents of Fuzi and FG. Chromatographic separation was achieved on a UFLC column using a gradient program with 40 mmol·L(-1) ammonium acetate and acetonitrile as the mobile phase. RESULTS: Fifty-one of the sixty compounds, including forty-five C19-diterpenoid alkaloids and six C20-diterpenoid alkaloids were tentatively identified in the extracts of Fuzi and FG through accurate mass measurements and fragmentation patterns. Comparing the contents of these alkaloids in these two extracts, it was found that the diester-diterpenoid alkaloids (DDAs) and the alkylolamine-diterpenoid alkaloids (ADAs) were increased, while the monoester-diterpenoid alkaloids (MDAs) were decreased in the extracts of FG. CONCLUSION: This work provided comprehensive information for the quality control of Fuzi preparations, and the further investigation on the compatibility mechanisms of FG.

Retinoic acid remodels extracellular matrix (ECM) of cultured human fetal palate mesenchymal cells (hFPMCs) through down-regulation of TGF-ß/Smad signaling.

The regulation of extracellular matrix (ECM) by retinoic acid (RA) is interesting in light of the fact that the ECM plays an essential role in morphogenesis and palatal shelf elevation. In the current study, we explored the effect of RA overexposure on ECM and the probable mechanisms in cultured human fetal palate mesenchymal cells (hFPMCs). RA dose-dependently inhibited cell proliferation and mRNA and protein levels of ECM components fibronectin, tenascin C and fibrillin-2. Zymography revealed that MMP-2 activity was suppressed by RA. Further analysis revealed that mRNA levels of MMP2 and TIMP2 were decreased, while the MMP2/TIMP2 mRNA ratio was increased, which might facilitate the ECM degradation. Because of the pivotal role of TGF-ß/Smad pathway in palatogenesis we therefore checked the effect of RA on TGF-ß/Smad signaling. The results indicated RA treatment increased Smad7 expression and decreased the levels of TGF-ß1, TGF-ß3, TGF-ß type II receptor (TßRII) and phosphorylated Smad2 and Smad3. Activation of the Smad pathways by either exogenous TGF-ß3 or recombinant adenoviruses for Smad3 attenuated RA-induced inhibition of cell proliferation and ECM components and rescued the RA-altered MMP2/TIMP2 mRNA ratio. In conclusion, these findings suggested that RA overexposure inhibited cell proliferation and disrupted the ECM network through down-regulation of TGF-ß/Smad pathway.

Grape seed extract attenuates arsenic-induced nephrotoxicity in rats.

Oxidative stress is a recognized factor in nephrotoxicity induced by chronic exposure to inorganic arsenic (As). Grape seed extract (GSE) possesses antioxidant properties. The present study was designed to evaluate the beneficial effects of GSE against arsenic-induced renal injury. Healthy, male Sprague-Dawley rats were exposed to As in drinking water (30 ppm) with or without GSE (100 mg/kg) for 12 months. The serum proinflammatory cytokine levels and mRNA expression levels of fibrogenic markers in the renal tissues were evaluated using enzyme-linked immunosorbent assay and quantitative polymerase chain reaction, respectively. The protein expression levels of nicotinamide adenine dinucleotide phosphate (NADPH) subunits, transforming growth factor-ß1 (TGF-ß1) and phosphorylated Smad2/3 (pSmad2/3) were assessed using western blot analysis. The results demonstrated that cotreatment with GSE significantly improved renal function, as demonstrated by the reductions in relative kidney weight (% of body weight) and blood urea nitrogen, and the increase in the creatinine clearance capacity. GSE attenuated the As-induced changes in the serum levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1ß and the mRNA levels of TGF-ß1, α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF) and fibronectin (FN) in renal tissue. Furthermore, administration of GSE markedly reduced As-stimulated reactive oxygen species (ROS) production and Nox activity, as well as the protein expression levels of the NADPH subunits (Nox2, p47phox and Nox4). In addition, GSE cotreatment was correlated with a significant reduction in TGF-ß/Smad signaling, as demonstrated by the decreased protein levels of TGF-ß1 and pSmad2/3 in renal tissue. This study indicated that GSE may be a useful agent for the prevention of nephrotoxicity induced by chronic exposure to As. GSE may exert its effects through the suppression of Nox and inhibition of TGF-ß/Smad signaling activation.

Discovery of safety biomarkers for realgar in rat urine using UFLC-IT-TOF/MS and 1H NMR based metabolomics.

As an arsenical, realgar (As4S4) is known as a poison and paradoxically as a therapeutic agent. However, a complete understanding of the precise biochemical alterations accompanying the toxicity and therapy effects of realgar is lacking. Using a combined ultrafast liquid chromatography (UFLC) coupled with ion trap time-of-flight mass spectrometry (IT-TOF/MS) and (1)H NMR spectroscopy based metabolomics approach, we were able to delineate significantly altered metabolites in the urine samples of realgar-treated rats. The platform stability of the liquid chromatography LC/MS and NMR techniques was systematically investigated, and the data processing method was carefully optimized. Our results indicate significant perturbations in amino acid metabolism, citric acid cycle, choline metabolism, and porphyrin metabolism. Thirty-six metabolites were proposed as potential safety biomarkers related to disturbances caused by realgar, and glycine and serine are expected to serve as the central contacts in the metabolic pathways related to realgar-induced disturbance. The LC/MS and NMR based metabolomics approach established provided a systematic and holistic view of the biochemical effects of realgar on rats, and might be employed to investigate other drugs or xenobiotics in the future.