Antioxidative effect of Periplaneta americana extract on dextran sulfate sodium-induced ulcerative colitis through activation of the Nrf2 signal.

CONTEXT: Periplaneta americana L. (Blattariae) is used as a treatment for ulcerative colitis (UC) in Chinese traditional medicine. OBJECTIVE: To evaluate the antioxidative activity of P. americana whole body ethanol extract (PAE) on UC mice and whether glycine and proline could be used for quality control and identification of active PAE components. MATERIALS AND METHODS: NCM460 cells were pre-incubated in PAE, AA-L, AA-M, and AA-H (low, high and medium doses of proline and glycine), then treated with recombinant human TNF-α. The glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD) and reactive oxygen (ROS) levels were determined. UC mice were fed with water containing 2.5% dextran sulfate sodium (w/v) after pre-treatment with different doses of PAE once a day for 7 days. ELISA was used to detect the concentrations of inflammation-related factors. Colon tissues of mice were used to detect the activity of myeloperoxidase (MPO), GSH, MDA, and SOD. Histological changes were observed using H&E staining. The expression of target proteins was determined by western blotting. RESULTS: In vivo, PAE treatment reduced the DAI score more than in the model group, restoring the weight and colonic length. It also reduced the severity of colitis, and inflammatory and oxidative stress intensity. Additionally, western blotting showed that the Nrf2 pathway was activated by PAE. In vitro PAE significantly alleviated TNF-α-induced cell damage and oxidative stress, which is relevant to the activation of the Nrf2 pathway. CONCLUSIONS: PAE may relieve oxidative stress through the Nrf2 signaling pathway, and proline and glycine may be used as active components of its antioxidative stress activity.

A novel Met-IR-782 near-infrared probe for fluorescent imaging-guided photothermal therapy in breast cancer.

In this work, a novel photothermal agent based on methionine (Met) was synthesized, which shows strong absorbance in the near infrared ray (NIR) region and is available for NIR imaging and in vivo photothermal therapy in a mouse model. Comparing to free IR-782, the obtained Met modified fluorescent dye (Met-IR-782) exhibited excellent fluorescence stability, preferable photothermal conversion efficiency under 780 nm laser irradiation and specific targeting to MCF7 (human breast adenocarcinoma cell line) cells. The fluorescence imaging ability enabled in situ monitoring of the tumor accumulation of Met-IR-782. The photothermal cytotoxicity assays in vitro and photothermal therapy treatments in vivo indicated that Met-IR-782 could efficiently target and suppress the growth of MCF7 xenograft tumors. Hence, Met-IR-782 is a potential fluorescent agent for NIR imaging-guided cancer photothermal therapy in clinical application. This work highlights the prospect of using light absorbing agents for NIR imaging-guided photothermal therapy.

Madecassoside impedes invasion of rheumatoid fibroblast-like synoviocyte from adjuvant arthritis rats via inhibition of NF-κB-mediated matrix metalloproteinase-13 expression.

Fibroblast-like synoviocytes (FLS) play a pivotal role in Rheumatoid arthritis (RA) pathogenesis through aggressive migration and invasion. Madecassoside (Madec), a triterpenoid saponin present in Centella asiatica herbs, has a potent anti-inflammatory effect. In the present study, Madec exerted an obvious therapeutic effect in reversing the histological lesions in adjuvant-induced arthritis (AIA) rats. To recognize the anti-rheumatoid potentials of Madec, we further investigated whether Madec interfered with FLS invasion and metalloproteinase (MMP) expression. In cultures of primary FLS isolated from the AIA rats, Madec (10 and 30 µmol·L-1) was proven to considerably inhibit migration and invasion of FLS induced by interleukin 1ß (IL-1ß), but exhibiting no obvious effect on cell proliferation. Madec repressed IL-1ß-triggered FLS invasion by prohibiting the expression of MMP-13. Additionally, Madec suppressed MMP-13 transcription via inhibiting the MMP-13 promoter-binding activity of NF-κB. Our results further showed that Madec down-regulated the translocation and phosphorylation of NF-κB as demonstrated by Western blotting and immunofluorescence assays. In conclusion, our results suggest that Madec exerts anti-RA activity via inhibiting the NF-κB/MMP-13 pathway.

Duplication and Loss of Function of Genes Encoding RNA Polymerase III Subunit C4 Causes Hybrid Incompatibility in Rice.

Reproductive barriers are commonly observed in both animals and plants, in which they maintain species integrity and contribute to speciation. This report shows that a combination of loss-of-function alleles at two duplicated loci, DUPLICATED GAMETOPHYTIC STERILITY 1 (DGS1) on chromosome 4 and DGS2 on chromosome 7, causes pollen sterility in hybrid progeny derived from an interspecific cross between cultivated rice, Oryza sativa, and an Asian annual wild rice, O. nivara Male gametes carrying the DGS1 allele from O. nivara (DGS1-nivaras ) and the DGS2 allele from O. sativa (DGS2-T65s ) were sterile, but female gametes carrying the same genotype were fertile. We isolated the causal gene, which encodes a protein homologous to DNA-dependent RNA polymerase (RNAP) III subunit C4 (RPC4). RPC4 facilitates the transcription of 5S rRNAs and tRNAs. The loss-of-function alleles at DGS1-nivaras and DGS2-T65s were caused by weak or nonexpression of RPC4 and an absence of RPC4, respectively. Phylogenetic analysis demonstrated that gene duplication of RPC4 at DGS1 and DGS2 was a recent event that occurred after divergence of the ancestral population of Oryza from other Poaceae or during diversification of AA-genome species.

Polymorphism of methylenetetrahydrofolate reductase gene is associated with response to fluorouracil-based chemotherapy in Chinese patients with gastric cancer.

BACKGROUND: The importance of polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene for the prediction of the response to fluorouracil-based adjuvant chemotherapy in gastric cancer patients remains unclear. The aim of this study is to assess the predictive value of several polymorphisms of the MTHFR gene for clinical outcomes of gastric cancer patients treated with fluorouracil-based adjuvant chemotherapy in Chinese population. METHODS: Three hundred and sixty-two Chinese patients with gastric cancer were treated with fluorouracil-based adjuvant chemotherapy. DNA samples were isolated from peripheral blood collected before treatment. The three single nucleotide polymorphisms (SNPs) (rs1801131, rs1801133, rs2274976) genotypes of the MTHFR gene were determined by matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). RESULTS: The average response rate for chemotherapy was 46.7%. Homozygous genotypes rs2274976G/G (χ(2) = 22.7, P < 0.01) and rs1801131A/A (χ(2) = 14.3, P = 0.008) were over-represented in responsive patients. Carriers of the rs2274976A allele genotypes (G/A and A/A) and of the rs1801131C allele genotypes (A/C and C/C) were prevalent in nonresponsive patients. In the haplotype association analysis, there was a significant difference in global haplotype distribution between the groups (χ(2) = 20.69, P = 0.000 124). CONCLUSIONS: These results suggest that polymorphisms of the MTHFR gene may be used as predictors of the response to fluorouracil-based chemotherapy for gastric cancer patients in Chinese population. Well-designed, comprehensive, and prospective studies on determining these polymorphisms of MTHFR gene as clinical markers for predicting the response to fluorouracil-based therapy in gastric cancer patients is warranted.

Polymorphisms of dihydropyrimidine dehydrogenase gene and clinical outcomes of gastric cancer patients treated with fluorouracil-based adjuvant chemotherapy in Chinese population.

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD), a key enzyme involved in the catabolism of 5-fluorouracil (5-FU), is the attractive candidate for pharmacogenetic research on efficacies and toxicities of 5-FU. The aim of this study is to explore the association between polymorphisms of dihydropyrimidine dehydrogenase gene (DPYD) and clinical outcomes of gastric cancer patients treated with fluorouracil-based adjuvant chemotherapy in the Chinese population. METHODS: Three hundred and sixty-two patients with gastric cancer in the Chinese population were treated with fluorouracil-based adjuvant chemotherapy. The single nucleotide polymorphic genotypes of DPYD were determined by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) using DNA samples isolated from peripheral blood collected before treatment. RESULTS: The average response rate for chemotherapy was 46.7%. A significantly different distribution of the rs1801159 (c2=8.76, P=0.012) genotypes was observed. Homozygous genotype rs1801159A/A was over-represented in responsive patients. Conversely, carriers of the rs1801159A/G genotype were prevalent in non-responsive patients. In the haplotype association analysis, there was significant difference in global haplotype distribution between the groups (c2=3.96, P=0.0465). CONCLUSIONS: These results suggest that polymorphisms of rs1801159 in DPYD may be used as valuable predictors of the response to fluorouracil-based chemotherapy for gastric cancer patients in the Chinese population. Well-designed, comprehensive, and prospective studies on determining these polymorphisms of DPYD as predictive markers for gastric cancer in response to fluorouracil-based therapies are warranted.

Reevaluation of the effect of Dianxianning on seizure rate of refractory epilepsy as additive treatment in clinical practice.

We observed the effect of Dianxianning, which was used as additive treatment to treat 206 epilepsy patients, on the epilepsy seizure rate. Based on a multicenter, prospective, randomized, and controlled clinical trial design, we used the seizure rate of epilepsy as the main index. For the treatment group comprising 137 patients, we combined Dianxianning with chemical medicine, which is the basic treatment. For the control group with 69 patients, we added placebo. The results showed that 1) Effect on seizure rate: After a three-month treatment, the seizure rate of the treatment group decreased by 37.84% on average, whereas that of the control group decreased by 13.18% on average. Statistically comparing the two groups, there was a significant difference between these groups (P < 0.05). 2) Effect on seizure frequency: As time passed, the frequency in each group gradually decreased. After a three-month treatment, there was a significant difference between the two groups (P < 0.05). 3) Comparison between the before and after treatment of each group: There was a very significant difference between the two groups (P < 0.0001). The results indicated that, as an additive treatment, Dianxianning has a good effect on controlling the epilepsy seizure rate and frequency management. It is more effective than using chemical medicine alone.

Mitochondrial gene in the nuclear genome induces reproductive barrier in rice.

Hybrid incompatibility in F(1) hybrids or later generations is often observed as sterility or inviability. This incompatibility acts as postzygotic reproductive isolation, which results in the irreversible divergence of species. Here, we show that the reciprocal loss of duplicated genes encoding mitochondrial ribosomal protein L27 causes hybrid pollen sterility in F(1) hybrids of the cultivated rice Oryza sativa and its wild relative O. glumaepatula. Functional analysis revealed that this gene is essential for the later stage of pollen development, and distribution analysis suggests that the gene duplication occurred before the divergence of the AA genome species. On the basis of these results, we discuss the possible contribution of the "founder effect" in establishing this reproductive barrier.

The ethylene response factors SNORKEL1 and SNORKEL2 allow rice to adapt to deep water.

Living organisms must acquire new biological functions to adapt to changing and hostile environments. Deepwater rice has evolved and adapted to flooding by acquiring the ability to significantly elongate its internodes, which have hollow structures and function as snorkels to allow gas exchange with the atmosphere, and thus prevent drowning. Many physiological studies have shown that the phytohormones ethylene, gibberellin and abscisic acid are involved in this response, but the gene(s) responsible for this trait has not been identified. Here we show the molecular mechanism of deepwater response through the identification of the genes SNORKEL1 and SNORKEL2, which trigger deepwater response by encoding ethylene response factors involved in ethylene signalling. Under deepwater conditions, ethylene accumulates in the plant and induces expression of these two genes. The products of SNORKEL1 and SNORKEL2 then trigger remarkable internode elongation via gibberellin. We also demonstrate that the introduction of three quantitative trait loci from deepwater rice into non-deepwater rice enabled the latter to become deepwater rice. This discovery will contribute to rice breeding in lowland areas that are frequently flooded during the rainy season.

Simultaneous determination of trilobolide-6-O-isobutyrates A and B in Wedelia trilobata by gas chromatography.

A simple, sensitive, and specific gas chromatographic (GC) method was developed to determine the main bioactive sesquiterpene lactones, trilobolide-6-O-isobutyrates A and B (TBO-A and TBO-B), in Wedelia trilobata, a useful folk herb. A commercially available HP-5 capillary column (30 m x 0.25 mm i.d. x 0.25 microm) was utilized for the direct determination of TBO-A and TBO-B in W. trilobata. Calibration curves were obtained by spiking authentic compounds and the internal standard (ferulic acid) into W. trilobata samples before extraction. Extraction was carried out by refluxing the dried herb (0.5 g) for 1 h in methanol (25 mL). All calibration curves showed good linear regressions (r2 > 0.992) within test ranges. The assay was reproducible and accurate with the overall intraday and interday relative standard deviations and accuracies of less than 10% and more than 90%, respectively. The developed GC method was successfully utilized to analyze the TBO-A and TBO-B in aerial parts and flowers of W. trilobata, indicating that it was suitable for the quality control of this commonly used herb and related traditional Chinese medicines.

[Relationship of methylenetetrahydrofolate reductase C677T polymorphism and chemosensitivity to 5-fluorouracil in gastric carcinoma].

BACKGROUND & OBJECTIVE: Methylenetrahydrofolate reductase (MTHFR) C677T polymorphism modifies enzyme activity and thus effects the level of 5, 10-methylenetetrahydrofolate (5,10-MTHR), which correlates with the tumor response to 5-fluorouracil (5-FU). This study was to evaluate the effect of MTHFR C677T polymorphism on chemosensitivity and toxicity to 5-FU in patients with gastric carcinoma. METHODS: A total of 75 patients with histologically confirmed advanced gastric carcinoma were included. All patients received 5-fluoropyrimidine-based chemotherapy. Two milliliters of peripheral blood was extracted from each patient before treatment. PCR-RFLP was used to determine the genotypes of MTHFR, including wild-type homozygotes (C/C), heterozygotes (C/T), and mutant homozygotes (T/T). RESULTS: C/C genotype presented in 24 patients (24/75, 32.0%), C/T genotype presented in 33 patients (33/75, 44.0%), and T/T genotype presented in 18 patients (18/75, 24.0%). Total response rate of chemotherapy was 29.3%, among which 22 with partial response, 29 with no change, and 24 with progressive disease. Response rate in patients with T/T genotype (20/24, 83.3%) was significantly greater than either that in patients with C/C genotype (2/24, 8.3%) (Chi2=24.01, P< 0.001), or that in patients with C/T genotype (5/33, 15.2%) (Chi2=22.7, P< 0.001). There was no difference of response rate between C/C and C/T genotypes (Chi2=0.6, P=0.439). Multiple variances logistic regression analysis (adjusted for gender, age, chemotherapy regimens, and adjuvant chemotherapy factors) showed that the probability of chemotherapy work on patients with combination of C/C and C/T genotypes was 0.017-fold to that in patients with T/T genotype (95% CI ranging from 0.003 to 0.102, P< 0.001); incidence of treatment-related side effects, vomiting and nausea, was significantly greater in latter patients than in former patients (Chi2=12.264, P=0.002). CONCLUSIONS: MTHFR C677T polymorphism can predict the effects and toxicity of 5-fluoropyrimidine-based chemotherapy in advanced gastric carcinoma.

[Polymorphism of methylenetetrahydrofolate reductase and sensitivity of stomach cancer to fluoropyrimidine-based chemotherapy].

OBJECTIVE: To investigate the relationship between polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) C677T or A1298C and the response to fluoropyrimidine (5-FU)-based chemotherapy in advanced stomach cancer (SC). METHODS: 75 cases with advanced SC were analyzed. All patients were treated with 5-FU-based chemotherapy and DNA of peripheral blood leukocytes was obtained before therapy. MTHFR genotypes were detected by PCR-RFLP method. RESULTS: (1) Of all the cases, the frequencies of MTHFR C677T C/C, C/T and T/T genotype were 32.0%, 44.0% and 24.0%, while the frequencies of MTHFR A1298C A/A, A/C and C/C genotype were 69.3%, 29.3% and 1.3%, respectively. The overal response rate to 5-FU-based chemotherapy was 29.3%. (2) The response rate to therapy among MTHFR C677T T/T genotype patients (83.3%) was significantly higher than the C677T C/T genotype (15.2%, chi(2) = 22.27, P = 0.000) or the C677T C/C genotype (8.3%, chi(2) = 23.44, P = 0.000). As compared with patients with C677T C allele, patients with C677T T/T genotype had a 7.64-fold sensitivity to 5-FU-based chemotherapy (adjusted for sex, age, prior adjuvant therapy and chemotherapy program, 95% CI: 3.14 - 18.62). The response rate to therapy among patients with MTHFR A1298C A/A genotype (36.5%) was significantly higher than patients with A1298C C allele (13.0%, chi(2) = 4.19, P = 0.041, adjusted OR = 3.75, 95% CI: 0.94 - 14.87). The response rate to therapy among patients with MTHFR C677T T/T and A1298C A/A genotypes (86.7%) was significantly higher than other groups of C677T and A1298C genotypes (15.0%, Fisher exact: P = 0.000, adjusted OR = 6.57, 95% CI: 2.8 - 15.6). (3) The incidence rates of nausea/vomiting in MTHFR C677T T/T, C/T or A1298C A/A genotypes were significantly higher than other genotypes, but the incidence rates of other treatment-related adverse reaction in MTHFR C677T or A1298C genotypes were not significantly different. CONCLUSION: These results in the present study suggested that the polymorphisms of MTHFR were associated with clinical response to 5-FU-based chemotherapy, suggesting that MTHFR genotypes could identify advanced SC patients that would be responsive to 5-FU-based chemotherapy.

[Interactions between lifestyle, methylanetetrahydrofolate reductase gene and polymorphisms in thymidylate synthase gene with risk of stomach cancer].

OBJECTIVE: To evaluate interactions between lifestyle, methylanetetrahydrofolate reductase gene (MTHFR) and polymorphisms in the 3'-untranslated region (3'-UTR) of the thymidylate synthase gene (TS) with reference to development of stomach cancer (SC). METHODS: We conducted a case-control study with 107 cases of SC and 200 population-based controls in Huaian city of Jiangsu province, China. TS genotypes were identified by polymerase chain reaction. RESULTS: (1) The frequencies of TS genotypes (+6 bp/+6 bp, +6 bp/-6 bp and -6 bp/-6 bp) among the cases were 5.6%, 47.7% and 46.7% and among the controls were 9.0%, 54.0% and 37.0%, respectively. Individuals identified as -6 bp/-6 bp genotype had a slightly higher risk for SC than those individuals with +6 bp alleles (the crude OR = 1.49, 95% CI: 0.90 - 2.47; adjusted OR = 1.36, 95% CI: 1.00 - 1.78, P = 0.047). (2) Individuals having TS -6 bp/-6 bp genotype and having smoking habit were at a significantly higher risk of developing SC (adjusted OR = 2.79, 95% CI: 1.51 - 5.18) compared with those who had +6 bp alleles with no smoking habit. Individuals having TS -6 bp/-6 bp genotype and habit of frequent alcohol drinking were at an increased risk of developing SC (adjusted OR = 1.76, 95% CI: 1.07 - 2.90) compared with those with +6 bp alleles and low consumption of alcohol. As compared with individuals with +6 bp alleles and who had habit of tea drinking, individuals who had TS -6 bp/-6 bp genotype and but without habit of tea drinking had an increased risk of developing SC (adjusted OR = 2.34, 95% CI: 1.43 - 3.82). (3) Individuals with TS -6 bp/-6 bp genotype and with MTHFR T alleles had an increased risk of developing SC (adjusted OR = 2.67, 95% CI: 1.07 - 6.70) compared with those with +6 bp alleles and with MTHRF C/C genotype. CONCLUSION: Results in the present study suggested that there was a combined effect between lifestyle, MTHFR C/T or T/T genotype and TS -6 bp/-6 bp genotype in the development of SC.