Synergistic effect of schizandrin A and DNase I knockdown on high glucose induced beta cell apoptosis by decreasing intracellular calcium concentration.

OBJECTIVE: To explore the synergistic effect of deoxyribonuclease I (DNase I) knockdown combined with Schizandrin A (Sch A) in protecting islet beta-cells (ß-cells) from apoptosis under high-glucose (HG) conditions. METHODS: The concentration of Sch A was detected by Cell Counting Kit-8 (CCK-8). High glucose-cultured rat insulinoma beta cell line (RIN-M5F) cells were treated with Sch A and transfected with DNase I small interfering RNA (siRNA). Cell apoptosis rate and apoptosis-related protein level were examined by flow cytometry and Western blot method respectively. In addition, Na-K-adenosine triphosphatease (Na-K-ATPase) and Ca-Mg-ATPase activity, cell membrane potential, and intracellular Ca concentration was also examined respectively. RESULTS: Our study revealed that HG stimulation can cause a significant increase in DNase I level and cell apoptosis rate. However, Sch A combined with DNase I knockdown can significantly decrease the cell apoptosis rate and apoptosis-related protein levels such as BAX ( 0.05) and Caspase-3 ( 0.01). In addition, we also found that the combination of Sch A and DNase I knockdown can dramatically increase cell membrane potential level, Na-K-ATPase, and Ca-Mg-ATPase activity. Meanwhile, intracellular Ca concentration was also found to be significantly decreased by the synergistic effect of Sch A and DNase I knockdown. CONCLUSION: Overall, our study reveals a synergistic effect of Sch A and DNase I knockdown in protecting ß-cells from HG-induced apoptosis.

Germline polymorphisms in genes involved in the Hippo pathway as recurrence biomarkers in stages II/III colon cancer.

The Hippo pathway regulates tissue growth and cell fate. In colon cancer, Hippo pathway deregulation promotes cellular quiescence and resistance to 5-Fluorouracil (5-Fu). In this study, 14 polymorphisms in 8 genes involved in the Hippo pathway (MST1, MST2, LATS1, LATS2, YAP, TAZ, FAT4 and RASSF1A) were evaluated as recurrence predictors in 194 patients with stages II/III colon cancer treated with 5-Fu-based adjuvant chemotherapy. Patients with a RASSF1A rs2236947 AA genotype had higher 3-year recurrence rate than patients with CA/CC genotypes (56 vs 33%, hazard ratio (HR): 1.87; P=0.017). Patients with TAZ rs3811715 CT or TT genotypes had lower 3-year recurrence rate than patients with a CC genotype (28 vs 40%; HR: 0.66; P=0.07). In left-sided tumors, this association was stronger (HR: 0.29; P=0.011) and a similar trend was found in an independent Japanese cohort. These promising results reveal polymorphisms in the Hippo pathway as biomarkers for stages II and III colon cancer.The Pharmacogenomics Journal advance online publication, 15 September 2015; doi:10.1038/tpj.2015.64.

Gender-specific profiling in SCN1A polymorphisms and time-to-recurrence in patients with stage II/III colorectal cancer treated with adjuvant 5-fluoruracil chemotherapy.

This study was designed to analyze the gender-related association between SCN1A polymorphisms (voltage-gated sodium channels; α-subunit) and time-to-recurrence (TTR) in patients with colorectal cancer (CRC) treated with 5-fluoruracil (5-FU)-based adjuvant chemotherapy. We enrolled from a prospective database patients with stage II and III CRC treated with adjuvant 5-FU-based chemotherapy. Genotypes for SCN1A rs3812718 and rs229877 were determined by direct DNA sequencing. One hundred twenty-seven males and 107 females were included in the study. In the univariate and multivariate analysis, the shortest TTR was associated with female patients carrying the rs3812718-TT genotype (hazard ratio (HR): 2.26 (95% confidence interval (CI): 0.89, 5.70), P=0.039) but with male patients carrying the rs3812718-CC genotype (HR: 0.49 (95% CI: 0.18, 1.38), P=0.048). For rs229877 the CT genotype was associated with a trend for shorter TTR in both gender populations. The study validated gender-dependent association between genomic SCN1A rs3812718 polymorphism and TTR in CRC patients treated with adjuvant 5-FU-based chemotherapy. This study confirms that voltage-gated Na+ channels may be a potential therapeutic target and a useful predictive biomarker before 5-FU infusion.

Association of common gene variants in the WNT/ß-catenin pathway with colon cancer recurrence.

Wnt/ß-catenin signaling has a central role in the development and progression of most colon cancers (CCs). Germline variants in Wnt/ß-catenin pathway genes may result in altered gene function and/or activity, thereby causing inter-individual differences in relation to tumor recurrence capacity and chemoresistance. We investigated germline polymorphisms in a comprehensive panel of Wnt/ß-catenin pathway genes to predict time to tumor recurrence (TTR) in patients with stage III and high-risk stage II CC. A total of 234 patients treated with 5-fluorouracil-based chemotherapy were included in this study. Whole-blood samples were analyzed for putative functional germline polymorphisms in SFRP3, SFRP4, DKK2, DKK3, Axin2, APC, TCF7L2, WNT5B, CXXC4, NOTCH2 and GLI1 genes by PCR-based restriction fragment-length polymorphism or direct DNA sequencing. Polymorphisms with statistical significance were validated in an independent study cohort. The minor allele of WNT5B rs2010851 T>G was significantly associated with a shorter TTR (10.7 vs 4.9 years; hazard ratio: 2.48; 95% CI, 0.96-6.38; P=0.04) in high-risk stage II CC patients. This result remained significant in multivariate Cox's regression analysis. This study shows that the WNT5B germline variant rs2010851 was significantly identified as a stage-dependent prognostic marker for CC patients after 5-fluorouracil-based adjuvant therapy.

Effects of dietary factors on selenium levels of children to prevent Kashin-Beck disease during a high-prevalence period in an endemic area: a cohort study.

Selenium (Se) supplements have been used to control Kashin-Beck disease (KBD) for decades, but the effect of diet without Se supplements is unclear because the prevalence of KBD has decreased. This matched cohort study was undertaken to determine dietary factors affecting selenium nutrition status of children living in KBD areas and the effects of Se supplements in preventing KBD. A total of 593 children aged 5-12 years were randomly selected during the high prevalence period of KBD from 1992 to 1995. Children in one village received Se supplemented (Se+) salt and were matched with three children in 16 other villages who did not receive Se supplemented (Se-) salt. A questionnaire and determinations of occipital hair Se to reflect body Se status were obtained at baseline (April 1992), at 6 months (October 1992), and yearly each April through 1995. Hair Se content in the Se+ group was significantly higher than in the Se- group (P < 0.001) at all time-points and was significantly related to the incidence of suspected KBD symptoms (P = 0.018). Four dietary factors significantly affected hair Se contents. Se levels were increased by consumption of Se+ salt (P < 0.001) and eating meat/egg often (P = 0.019) or occasionally (P = 0.001). Se levels were decreased by consumption of grain mildewed at harvest or in storage (P < 0.001 for each) and drinking ditch, river, or cellar water (P < 0.001; P = 0.002; P < 0.001, respectively). These results show that Se+ salt had a significant effect in maintaining the Se nutrition status of children in this cohort study but that dietary factors in those without Se supplements contributed as well.

Effects of preventive acupuncture on streptozotocin-induced hyperglycemia in rats.

BACKGROUND: Diabetes prevention has received increasing attention recently. Clinical and experimental studies showed that acupuncture could produce hypoglycemic effect. However, little is known about the effectiveness of acupuncture in diabetes prevention. AIM: To investigate the preventive effects of acupuncture on streptozotocin (STZ)-induced hyperglycemia in rats. METHODS: Hyperglycemia was induced by a single intraperitoneal injection of STZ (60 mg/kg). Rats were randomly divided into six groups (no.=8 each group): control, diabetes, preventive acupuncture plus STZ injection, STZ injection plus therapeutic acupuncture, STZ injection plus preventive and therapeutic acupuncture, and preventive and therapeutic acupuncture control. Body weight, blood glucose, serum insulin, lipid peroxidation, and antioxidant enzymes were measured by routine standard methods. Histological analysis of pancreatic islets was conducted. RESULTS: Preventive acupuncture significantly relieved hyperglycemia, insulin deficiency, weight loss, and pancreatic islet damage in rats with STZ injection; it also significantly reduced serum lipid peroxidation and enhanced superoxide dismutase in the serum and the pancreas without significantly affecting serum glutathione peroxidase and catalase. Therapeutic acupuncture exhibited a hypoglycemic effect in the late stage, but did not significantly improve other parameters. CONCLUSIONS: These results indicate that preventive acupuncture is beneficial to the control of STZ-induced hyperglycemia in rats.

Tumor disposition of pegylated liposomal CKD-602 and the reticuloendothelial system in preclinical tumor models.

Liposomes, such as pegylated-liposomal CKD-602 (S-CKD602), undergo catabolism by macrophages and dendritic cells (DCs) of the reticuloendothelial system (RES). The relationship between plasma and tumor disposition of S-CKD602 and RES was evaluated in mice bearing A375 melanoma or SKOV-3 ovarian xenografts. Area under the concentration-time curves (AUCs) of liposomal encapsulated, released, and sum total (encapsulated + released) CKD-602 in plasma, tumor, and tumor extracellular fluid (ECF) were estimated. A375 and SKOV-3 tumors were stained with cd11b and cd11c antibodies as measures of macrophages and DC. The plasma disposition of S-CKD602 was similar in both xenograft models. The ratio of tumor sum total AUC to plasma sum total AUC was 1.7-fold higher in mice bearing human SKOV-3 xenografts, compared with A375. The ratio of tumor ECF AUC to tumor sum total AUC was 2-fold higher in mice bearing human SKOV-3 xenografts, compared with A375. The staining of cd11c was 4.5-fold higher in SKOV-3, compared with A375 (P < 0.0001). The increased tumor delivery and release of CKD-602 from S-CKD602 in the ovarian xenografts, compared with the melanoma xenografts, was consistent with increased cd11c staining, suggesting that variability in the RES may affect the tumor disposition of liposomal agents.

Preterm delivery risk in relation to maternal HIV infection, history of malaria and other infections among urban Zimbabwean women.

OBJECTIVE: To examine preterm delivery risk in relation to maternal HIV infection, malaria history, and other infections among Zimbabwean women. DESIGN: Hospital based, cross sectional study. SETTING: Harare Maternity Hospital, Harare, Zimbabwe. SUBJECTS: A convenient sample of 500 pregnant women. MAIN OUTCOME MEASURE: Preterm delivery. THE STUDY FACTORS: Maternal socio-demographic information, and infectious disease history (during the year before pregnancy). METHOD: Between July 1998 and March 1999 data were collected for a cross sectional study of pregnant women who delivered at the Harare Maternal Hospital. The association of maternal HIV infection, history of malaria, and other infections with preterm delivery were determined using multivariate analysis. RESULTS: Overall, 497 women were studied, 444 (89.3%) delivered at term and 53 women (10.7%) delivered preterm. Women who delivered preterm were less likely to be HIV seropositive compared with others (odds ratio [OR] = 0.75. 95% confidence interval (CI): 0.38 to 21.48). Preterm delivery was associated with having tuberculosis infections in the year prior to the pregnancy (OR = 10.15, 95% CI: 1.15 to 89.87). Other infections associated with preterm delivery were malaria (OR = 2.39, 95% CI: 1.07 to 5.31), chest infections (OR = 2.63, 95% CI: 0.76 to 9.17), and Herpes (shingles) infection (OR = 2.58, 95% CI: 0.56 to 11.85). Overall, a positive history of any of the non-sexually transmitted infections (in aggregate) was associated with a 3.20 fold increase risk for preterm delivery (OR = 3.20. 95% CI: 1.59 to 6.43). Women with a history of infection and who did not use iron supplements during pregnancy, compared with women without such an history and who used iron supplements, experienced the highest risk for preterm delivery (OR = 8.34, 95% CI: 3.30 to 21.07). CONCLUSION: Maternal non-STD infections, (i.e., tuberculosis, malaria, and chest infections) occurring in the year prior to pregnancy were associated with an increased risk of preterm delivery. The association of non-sexually transmitted infections and preterm delivery was particularly strong among women who did not use iron supplements during pregnancy.

Chemoprevention of aflatoxin B1-initiated and carbon tetrachloride-promoted hepatocarcinogenesis in the rat by green tea.

Chemoprevention of hepatocarcinogenesis by green tea (GT) has been examined in young male Fischer rats fed AIN-76A diet with aflatoxin B1 (AFB1) and CCl4 as the initiator and promoter, respectively. Animals were administered AFB1 (0.25 mg/kg body wt ip) twice a week for 2 weeks, and 2 weeks later, CCl4 was injected (0.8 ml/kg body wt ip) once per week for 11 weeks. Rats given 0.5% GT in their drinking water before and during initiation (0-4 wk) or during promotion (6-16 wk) or throughout the experimental period were sacrificed 24 hours after the last dose of CCl4. Bromodeoxyuridine incorporation as a measure of cell proliferation and glutathione S-transferase placentalform- and gamma-glutamyl transpeptidase-positive hepatic foci were analyzed by histochemical methods. Feeding of GT during initiation or promotion inhibited the number of glutathione S-transferase placental form- and gamma-glutamyl transpeptidase-positive hepatic foci by 30-40% and the area and volume by 50%. GT treatment throughout the period inhibited the number of both types of hepatic foci by 60% and the area and volume by 75-80%. Cell proliferation was inhibited 35% by GT given during promotion, whereas inhibition was 65% when GT was given during initiation or throughout the period. These results indicate that GT feeding inhibits initiation and promotion steps of AFB1 hepatocarcinogenesis and that the inhibition of cell proliferation is responsible for the inhibition of promotion.

[Effect of emodin on human kidney fibroblast proliferation].

OBJECTIVE: To study the effect of emodin on proliferation of human kidney fibroblasts in vitro. METHODS: After human kidney fibroblasts were cultured, isolated and identified, both the effects of five different concentrations of emodin (10, 30, 50, 80 and 100 micrograms/ml) on 3H-TdR incorporation, and the effects of three different concentrations of emodin (10, 50 and 100 micrograms/ml) on cell cycle by flow cytometry were investigated. RESULTS: The exposure of human kidney fibroblasts to emodin (10-100 micrograms/ml) caused a dose-dependent reduction in 3H-TdR (r = 0.995, P < 0.01), and could delay the progress of human kidney fibroblasts from G1 to S phase. CONCLUSIONS: Emodin inhibited the proliferation of human kidney's fibroblasts by inhibiting the cell DNA synthase and delaying the progress of cell cycle. These findings might provide part of experimental basis for the clinical use of emodin.

Inhibition of aflatoxin B1-induced initiation of hepatocarcinogenesis in the rat by green tea.

Several studies have demonstrated that green tea (GT) inhibits various chemically induced cancers in experimental animals. In the present study, effect of GT has been examined on the initiation of aflatoxin B1 (AFB1)-induced hepatocarcinogenesis in the rat. Young male Fischer rats were given AIN-76A diet with or without 0.5% instant GT powder in their drinking water for 2 or 4 weeks. Initiation was examined by hepatic AFB1-DNA binding in vivo, AFB1 metabolism in vitro and by the appearance of AFB1-induced glutathione S-transferase placental form (GST-P)-positive hepatocytes detected by immunohistochemical method. There was no influence of GT feeding on microsome-mediated AFB1 binding to exogenous DNA. However, GT feeding enhanced microsome-mediated formation of non-toxic hydroxylated metabolites of AFB1 by 2-3-fold. Hepatic nuclear AFB1-DNA binding in vivo was significantly inhibited by about 20-30% in animals pretreated with GT: AFB1-induced GST-P positive single hepatocytes were inhibited significantly by 60-70% in rats pretreated with GT. These results suggest that feeding of GT inhibits initiation of AFB1-induced hepatocarcinogenesis in the rat by modulation of AFB1 metabolism, thereby inhibiting AFB1-DNA binding and AFB1-induced GST-P-positive hepatocytes.