Effects of Helicobacter pylori and Moluodan on the Wnt/ß-catenin signaling pathway in mice with precancerous gastric cancer lesions.

BACKGROUND: Helicobacter pylori (H. pylori) is the primary risk factor for gastric cancer (GC), the Wnt/ß-Catenin signaling pathway is closely linked to tumourigenesis. GC has a high mortality rate and treatment cost, and there are no drugs to prevent the progression of gastric precancerous lesions to GC. Therefore, it is necessary to find a novel drug that is inexpensive and preventive to against GC. AIM: To explore the effects of H. pylori and Moluodan on the Wnt/ß-Catenin signaling pathway and precancerous lesions of GC (PLGC). METHODS: Mice were divided into the control, N-methyl-N-nitrosourea (MNU), H. pylori + MNU, and Moluodan groups. We first created an H. pylori infection model in the H. pylori + MNU and Moluodan groups. A PLGC model was created in the remaining three groups except for the control group. Moluodan was fed to mice in the Moloudan group ad libitum. The general condition of mice were observed during the whole experiment period. Gastric tissues of mice were grossly and microscopically examined. Through quantitative real-time PCR (qRT-PCR) and Western blotting analysis, the expression of relevant genes were detected. RESULTS: Mice in the H. pylori + MNU group showed the worst performance in general condition, gastric tissue visual and microscopic observation, followed by the MNU group, Moluodan group and the control group. QRT-PCR and Western blotting analysis were used to detect the expression of relevant genes, the results showed that the H. pylori + MNU group had the highest expression, followed by the MNU group, Moluodan group and the control group. CONCLUSION: H. pylori can activate the Wnt/ß-catenin signaling pathway, thereby facilitating the development and progression of PLGC. Moluodan suppressed the activation of the Wnt/ß-catenin signaling pathway, thereby decreasing the progression of PLGC.

[Bifidobacterium bifidum TMC3115 Promotes Early Life Intestinal Microbiota Building to Alleviate Symptoms of Inflammatory Bowel Disease].

Objective: To investigate the effects of using Bifidobacterium bifidum TMC3115 in early life on intestinal microbiota and immune functions and the long-term impact on inflammatory bowel disease. Methods: Fourteen pregnant BALB/c mice were purchased and 84 newborn BALB/c mice were subsequently obtained. Then, the newborn mice were randomly assigned to a normal saline (NS) group and a TMC3115 group, given via oral gavage normal saline and TMC3115, respectively, at a daily volume of 0.2 mL for each mouse. About 42 mice were assigned to each group. The gavage was stopped after 3 weeks. At this point, half of the mice in each group were sacrificed, and then the remaining mice in each group were randomly divided into NS-water group, NS-DSS group, TMC3115-water group, and TMC3115-DSS group, with about 10 mice in each group. The mice were given regular feed until the end of week 6 when they were given 3% dextran sulphate sodium (DSS) ad libitum for 4 days to establish the enteritis model, while the non-modeling groups were given pure water ad libitum. The experiment ended after 6 weeks and 4 days. The weekly body mass changes of the mice were documented. The intestinal tissue at the end of the experiment and the fecal samples, spleen and serum of the mice at 3 weeks and at the end of the experiment were collected to determine the pathology scores of colonic inflammation, the composition of fecal gut microbiota, spleen organ index and the mass concentration of serum cytokines. Results: 1) At the end of the experiment, the inflammatory pathology score was significantly lower in the TMC3115-DSS group compared with that of the Saline-DSS group ( P<0.05), with less disruption of colonic crypt structures and other structures, less inflammatory infiltration, and more intact epithelial structures. 2) At 3 weeks, in comparison with those of the NS group, the relative abundance of Bifidobacteriumwas significantly higher in the feces of the TMC3115 ( P<0.05), the relative abundance of both Enterococcusand Staphylococcuswas lower ( P<0.05), the splenic organ index was significantly higher ( P<0.05), and interleukin (IL)-10 was significantly decreased ( P<0.05), while there was no significant change in IL-6 or TNF-α ( P>0.05). At the end of the experiment, in comparison with those of the NS-DSS group that undergone DSS induction, the TMC3115-DSS group had reduced relative abundance of Staphylococcus, Staphylococcus tumefaciens and Escherichia/ Shigellain the feces ( P<0.05), while the splenic organ index was significantly higher ( P<0.05), and there were no significant changes in IL-6 or TNF-α ( P>0.05). Conclusion: The use of TMC3115 in early life promotes the construction of gut microbiota in neonatal mice, thereby producing a long-term effect that alleviates colitis in mice, but the mechanisms involved are still not fully understood.

Reversible preoperative renal dysfunction does not add to the risk of postoperative acute kidney injury after cardiac valve surgery.

OBJECTIVE: To evaluate the impact of the renal dysfunction (RD) type and change of postoperative cardiac function on the risk of developing acute kidney injury (AKI) in patients who underwent cardiac valve surgery. METHOD: Reversible renal dysfunction (RRD) was defined as preoperative RD in patients who had not been initially diagnosed with chronic kidney disease (CKD). Cardiac function improvement (CFI) was defined as postoperative left ventricular ejection function - preoperative left ventricular ejection function (ΔEF) >0%, and cardiac function not improved (CFNI) as ΔEF ≤0%. RESULTS: Of the 4,805 (94%) cardiac valve surgery patients, 301 (6%) were RD cases. The AKI incidence in the RRD group (n=252) was significantly lower than in the CKD group (n=49) (36.5% vs 63.3%, P=0.018). The AKI and renal replacement therapy incidences in the CFI group (n=174) were significantly lower than in the CFNI group (n=127) (33.9% vs 50.4%, P=0.004; 6.3% vs 13.4%, P=0.037). After adjustment for age, gender, and other confounding factors, CKD and CKD + CFNI were identified as independent risk factors for AKI in all patients after cardiac valve surgery. Multivariate logistic regression analysis showed that the risk factors for postoperative AKI in preoperative RD patients were age, gender (male), hypertension, diabetes, chronic heart failure, cardiopulmonary bypass time (every 1 min added), and intraoperative hypotension, while CFI after surgery could reduce the risk. CONCLUSION: For cardiac valve surgery patients, preoperative CKD was an independent risk factor for postoperative AKI, but RRD did not add to the risk. Improved postoperative cardiac function can significantly reduce the risk of postoperative AKI.

AMPK activator acadesine fails to alleviate isoniazid-caused mitochondrial instability in HepG2 cells.

Isoniazid (INH) is a first-line antituberculosis drug that is adversely associated with hepatotoxicity. Recently, impairment of mitochondrial homeostasis involved in this side effect has been noticed. Mitochondrial homeostasis is achieved by the balance between the generation of functional mitochondria by biogenesis and elimination of dysfunctional mitochondria by autophagy. AMP-activated protein kinase (AMPK) can maintain mitochondrial stability through positive control of these two processes. In this study, we showed that AMPK activator acadesine (AICAR) alleviated INH-caused impairment of mitochondrial biogenesis by activation of silent information regulator two ortholog 1 (SIRT1)-peroxisome proliferator-activated receptor γ coactivator 1α (PGC1 α) pathway in HepG2 cells. However, mitochondrial instability and apoptosis were caused by AICAR along with an unexpected decrease in INH-induced cytoprotective autophagy. Therefore, AICAR failed to alleviate INH-caused mitochondrial instability in HepG2 cells due to its inhibitory effect on autophagy induced by INH. Copyright © 2017 John Wiley & Sons, Ltd.

Silica nanoparticles and lead acetate co-exposure triggered synergistic cytotoxicity in A549 cells through potentiation of mitochondria-dependent apoptosis induction.

The adverse effects of PM2.5 are the results of combined toxicities of finer particles and their adsorbed toxic pollutants. Nevertheless, the combined toxicity of finer particles and air pollutants still remains unclear. The present study was therefore undertaken to investigate the combined cytotoxicity of silica nanoparticles (nano-SiO2, a typical atmospheric ultrafine particle) and lead acetate (Pb, a representative air pollutant) in A549 cells focusing on mitochondria-dependent apoptosis induction. The results showed that Pb exposure alone induced mitochondria-dependent apoptosis in A549 cells, as evidenced by increased apoptotic rate and Bax/Bcl-2 ratio, up-regulated caspases 3 and 9 expressions as well as decreased mitochondrial membrane potential. Non-cytotoxic concentration of nano-SiO2 exposure alone did not trigger apoptosis in A549 cells, but potentialized the apoptotic changes when co-exposure with Pb. Factorial analyses revealed synergistic interactions were responsible for the potentiation of joint apoptotic responses.

Metallothionein protects against isoniazid-induced liver injury through the inhibition of CYP2E1-dependent oxidative and nitrosative impairment in mice.

Oxidative stress mediated by hepatic CYP2E1 during isoniazid (INH) metabolism is considered responsible for INH hepatotoxicity. This study attempts to determine whether metallothionein (MT), a cysteine-rich antioxidant can protect against INH-induced liver injury by using a MT-I/II deficient mouse model (MT-/- mice). MT-/- mice and the corresponding wild-type mice received intragastric administrations of 0, 75, 150 and 300 mg/kg of INH for 15 days. The results showed that 150 and 300 mg/kg of INH induced liver injury in both types of mice, as evidenced by increased liver index and histopathological change of liver vacuolar degeneration. Increased hepatic MDA level and 3-NT expression, and decreased GSH content and SOD activity were also observed in both types of mice, indicating the involvement of oxidative and nitrosative stress. INH treatment upregulated hepatic CYP2E1 expression in both types of mice, and the severity of liver injury was in concert with the elevation of CYP2E1 expression. Comparative analyses revealed liver vacuolar degeneration and oxidative and nitrosative stress were more severe in MT-/- mice than wild-type mice, suggesting the hepatoprotection of MT against INH hepatotoxicity. Taken together, these findings clearly demonstrate that MT protects against INH-induced liver toxicity by ameliorating CYP2E1-dependent oxidative and nitrosative impairment.

Significance of perioperative goal-directed hemodynamic approach in preventing postoperative complications in patients after cardiac surgery: a meta-analysis and systematic review.

PURPOSE: Goal-directed hemodynamic therapy (GDT) is used to prevent hypoperfusion resulting from surgery. The objective of this study was to analyze the efficacy and importance of perioperative GDT. METHODS: PUBMED, MEDLINE, CENTRAL, and Google Scholar databases were searched until 17 June 2016 using the search terms: cardiac output, cardiac surgical procedures, hemodynamics, goal-directed therapy, and intraoperative. Randomized-controlled trials with pre-emptive hemodynamic intervention for cardiac surgical population versus standard hemodynamic therapy were included. RESULTS: Nine studies were included with a total of 1148 patients. The overall analysis revealed no significant difference in the all-cause mortality (pooled peto OR =0.58, 95%CI =0.27-1.525, p = 0.164), duration of mechanical ventilation (pooled difference in mean= -1.48, 95%CI= -3.24 to 0.28, p = 0.099), or length of intensive care unit (ICU) stay (pooled difference in mean= -9.10, 95%CI= -20.14 to 1.93, p = 0.106) between patients in the GDT and control groups. Patients in the GDP group were associated with shorter hospital stay than those in the control group (pooled difference in mean= -1.52, 95%CI= -2.31 to -0.73, p < 0.001). CONCLUSION: GDT reduces the length of hospital stay compared with the standard of care. Further studies are necessary to continually assess the benefit of GDT following major surgery. Key Messages The results of this analysis revealed no significant difference between cardiac surgery patients receiving goal-directed hemodynamic therapy (GDT) or conventional fluid therapy in terms of the all-cause mortality, duration of mechanical intervention, and length of ICU-stay. The length of hospital stay was significantly reduced in patients treated with GDT compare to conventional fluid therapy. GDT may have limited benefit in reducing mortality; however, the association to shorter length of hospital stay may suggest that better hemodynamic balance can facilitate postoperative recovery.

Prepubertal exposure to an oestrogenic mycotoxin zearalenone induces central precocious puberty in immature female rats through the mechanism of premature activation of hypothalamic kisspeptin-GPR54 signaling.

Sporadic epidemics and several researches in rodents indicated that zearalenone (ZEA) and its metabolites, the prevailing oestrogenic mycotoxins in foodstuffs, were a triggering factor for true precocious puberty development in girls. Nevertheless, the neuroendocrine mechanism through which ZEA mycoestrogens advance puberty onset is not fully understood. To elucidate this issue, hypothalamic kisspeptin-G-protein coupled receptor-54 (GPR54) signaling pathway that regulates the onset of puberty was focused on in the present study. Immature female SD rats were given a daily intragastric administration of corn oil (vehicle control), 50 µg/kg body weight (bw) of 17ß-estradiol (E2, positive control), and 3 doses (0.2, 1 and 5 mg/kg bw) of ZEA for consecutive 5 days starting from postnatal day 15, respectively. Puberty onset was evaluated by detecting the physiological and hormonal responses, and hypothalamic kisspeptin-GPR54 pathway was determined to reveal the neuroendocrine mechanism. As the markers of puberty onset, vaginal opening was significantly accelerated and uterine weight was increased in both E2 and 5 mg/kg ZEA groups. Serum levels of follicle stimulating hormone, luteinizing hormone and estradiol were also markedly elevated by E2 and 5 mg/kg ZEA, which is compatible with the changes in peripheral reproductive organs. The mRNA and protein expressions of hypothalamic gonadotropin-releasing hormone (GnRH) were both obviously elevated by E2 and 5 mg/kg ZEA. GnRH expression changes occurred in parallel with increased expressions of hypothalamic Kiss1 and its receptor GPR54 at both mRNA and protein levels. Most of these changes were also noted in 1 mg/kg ZEA group, but none in 0.2 mg/kg group. Therefore, within the context of this study, the No Observed Adverse Effect Level (NOAEL) for ZEA in terms of oestrogenic activity and puberty-promoting effect in immature female rats was considered to be 0.2 mg/kg bw per day, and the Lowest Observed Adverse Effect Level (LOAEL) was 1 mg/kg bw per day. In conclusion, prepubertal exposure to dietary relevant levels of ZEA induced central precocious puberty in female rats by premature activation of hypothalamic kisspeptin-GPR54-GnRH signaling pathway, followed by the stimulation of gonadotropins release at an earlier age, resulting in the advancement of vaginal opening and enlargement of uterus at periphery.

Induction of protective autophagy against apoptosis in HepG2 cells by isoniazid independent of the p38 signaling pathway.

Isoniazid (INH), one of the first-line anti-tuberculosis drugs, is adversely associated with hepatotoxicity in the clinic. However, the detailed mechanism of this side effect is still unclear. The traditional theory that cytochrome P450 2E1 is involved in INH-induced hepatotoxicity remains controversial, therefore other mechanisms by which INH exerts hepatotoxicity need to be investigated. In the current study, we showed that in vitro treatment of human hepatocarcinoma HepG2 cells with INH induced caspase-dependent apoptosis through extrinsic and intrinsic pathways. It was characterized by the increased population of apoptotic cells using Annexin V/propidium iodide (PI) double staining by flow cytometry, and by the activation of caspases 8, 9, 3 and poly (ADP-ribose)-polymerase (PARP) proteins by western blotting. INH treatment also induced autophagy as shown by the upregulated levels of microtubule-associated protein 1 light chain 3-II (LC3-II), increased GFP-LC3 punctates, and elevated monodansylcadaverine (MDC) fluorescence intensity. The measurement of the autophagic flux using chloroquine (CQ) confirmed that INH stimulated autophagy but did not inhibit it by impairing lysosomal degradation. The blockage of autophagy with CQ exacerbated INH-induced apoptosis significantly. Further study showed that INH treatment down-regulated the protein phosphorylation of the mammalian target of rapamycin (mTOR), the key negative regulator of autophagy. In addition, INH induced p38 signaling activation. SB203580, a p38 inhibitor, effectively enhanced INH-induced apoptosis by increasing the cleavages of caspases 9, 3 and PARP, but did not affect autophagy. In summary, we firstly found that INH induced a protective autophagy which was associated with the inhibition of the mTOR pathway, and that INH induced p38 signaling activation to inhibit apoptosis by down-regulation of caspases 9, 3 and PARP pathways, but not that of autophagy. Thus, activation of autophagy and p38 signaling is presumably a therapeutic strategy for INH-induced hepatotoxicity.

Delay of the onset of puberty in female rats by prepubertal exposure to T-2 toxin.

Growing evidence has revealed the deleterious influence of environmental and food contaminants on puberty onset and development in both animals and children, provoking an increasing health concern. T-2 toxin, a naturally-produced Type A trichothecene mycotoxin which is frequently found in cereal grains and products intended for human and animal consumption, has been shown to impair the reproduction and development in animals. Nevertheless, whether this trichothecene mycotoxin can disturb the onset of puberty in females remains unclear. To clarify this point, infantile female rats were given a daily intragastric administration of vehicle or 187.5 µg/kg body weight of T-2 toxin for five consecutive days from postnatal day 15 to 19, and the effects on puberty onset were evaluated in the present study. The results revealed that the days of vaginal opening, first dioestrus, and first estrus in regular estrous cycle were delayed following prepubertal exposure to T-2 toxin. The relative weights of reproductive organs uterus, ovaries, and vagina, and the incidence of corpora lutea were all diminished in T-2 toxin-treated rats. Serum levels of gonadotropins luteinizing hormone, follicle-stimulating hormone, and estradiol were also reduced by T-2 toxin treatment. The mRNA expressions of hypothalamic gonadotropin-releasing hormone (GnRH) and pituitary GnRH receptor displayed significant reductions following exposure to T-2 toxin, which were consistent with the changes of serum gonadotropins, delayed reproductive organ development, and delayed vaginal opening. In conclusion, the present study reveals that prepubertal exposure to T-2 toxin delays the onset of puberty in immature female rats, probably by the mechanism of disturbance of hypothalamic-pituitary-gonadal (HPG) axis function. Considering the vulnerability of developmental children to food contaminants and the relative high level of dietary intake of T-2 toxin in children, we think the findings of the present study provide valuable information for the health risk assessment in children.

Combined exposure to nano-silica and lead induced potentiation of oxidative stress and DNA damage in human lung epithelial cells.

Growing evidence has confirmed that exposure to ambient particulate matters (PM) is associated with increased morbidity and mortality of cardiovascular and pulmonary diseases. Ambient PM is a complex mixture of particles and air pollutants. Harmful effects of PM are specifically associated with ultrafine particles (UFPs) that can adsorb high concentrations of toxic air pollutants and are easily inhaled into the lungs. However, combined effects of UFPs and air pollutants on human health remain unclear. In the present study, we elucidated the combined toxicity of silica nanoparticles (nano-SiO2), a typical UFP, and lead acetate (Pb), a typical air pollutant. Lung adenocarcinoma A549 cells were exposed to nano-SiO2 and Pb alone or their combination, and their combined toxicity was investigated by focusing on cellular oxidative stress and DNA damage. Factorial analyses were performed to determine the potential interactions between nano-SiO2 and Pb. Our results showed that exposure of A549 cells to a modest cytotoxic concentration of Pb alone induced oxidative stress, as evidenced by elevated reactive oxygen species generation and lipid peroxidation, and reduced glutathione content and superoxide dismutase and glutathione peroxidase activities. In addition, exposure of A549 cells to Pb alone induced DNA damage, as evaluated by alkaline comet assay. Exposure of A549 cells to non-cytotoxic concentration of nano-SiO2 did not induce cellular oxidative stress and DNA damage. However, exposure to the combination of nano-SiO2 and Pb potentiated oxidative stress and DNA damage in A549 cells. Factorial analyses indicated that the potentiation of combined toxicity of nano-SiO2 and Pb was induced by additive or synergistic interactions.

A Ni-free ZrCuFeAlAg bulk metallic glass with potential for biomedical applications.

The mechanical properties and biocompatibility of an Ni-free Zr-based bulk metallic glass (BMG) Zr60.14Cu22.31Fe4.85Al9.7Ag3 were investigated in detail to evaluate its potential as a biomaterial. The BMG was found to have a low Young's modulus of 82±1.9GPa, a high strength of 1720±28MPa and a high fracture toughness of 94±19MPam(1/2), as well as good fatigue strength over 400MPa. The corrosion behavior of the alloy was investigated in simulated body fluid (SBF) by electrochemical measurements, which indicates that the Zr-based BMG has a better corrosion resistance than pure Zr and Ti6Al4V. X-ray photoelectron spectroscopy analysis revealed that the passive film formed on the BMG surface is enriched in Al- and Zr-oxides, which could account for the good corrosion resistance of the BMG. On the other hand, metal ion release of the BMG in SBF was determined by inductively coupled plasma mass spectrometry after the BMG was immersed in SBF at 37°C for 30days, showing a ppb (ngml(-1)) level of metal ion release. The in vitro test via cell culture indicates that the BMG exhibits a cytotoxicity of Grade 0-1, which is as good as Ti6Al4V alloy. Cell adhesion morphological analysis shows that the cells were flattened and well spread out on the surfaces of the BMG, showing that the BMG had good biocompatibility. The combination of good mechanical properties and biocompatibility demonstrates that the Ni-free Zr-based BMG studied in this work is a good candidate for a new type of load-bearing biomedical material.

Skin denervation and its clinical significance in late-stage chronic kidney disease.

OBJECTIVE: To investigate the skin innervation and its clinical significance in late-stage chronic kidney disease (CKD). DESIGN: Case series. SETTING: National Taiwan University Hospital, Taipei, Taiwan. PATIENTS: Forty consecutive nondiabetic patients with late-stage CKD (14 female and 26 male; mean [SD] age, 60.7 [12.3] years), including 2 cases with stage 3 CKD, 6 with stage 4 CKD, and 32 with stage 5 CKD, ie, end-stage kidney disease. INTERVENTIONS: Clinical evaluation of neurological deficits, nerve conduction study, autonomic function tests, and a 3-mm-diameter skin biopsy specimen taken from the distal leg. MAIN OUTCOME MEASURES: Quantitation of epidermal innervation, parameters of nerve conduction study, R-R interval variability, and sympathetic skin response. RESULTS: Clinically, 21 patients (52.5%) were symptomatic with paresthesia over the limbs or autonomic symptoms. The intraepidermal nerve fiber (IENF) density was markedly reduced in patients with CKD compared with age- and sex-matched controls (mean [SD], 2.8 [2.0] vs 8.6 [2.8] fibers/mm; P < .001). Skin denervation was observed in 27 patients (67.5%). Fifteen patients (37.5%) had abnormalities on nerve conduction studies, and 29 patients (72.5%) had abnormal results on autonomic function tests. By analysis with multiple regression models, the IENF density was negatively correlated with the duration of renal disease (P = .02). Additionally, the R-R interval variability at rest was linearly correlated with the IENF density (P = .02) and the absence of sympathetic skin responses at the soles was associated with reduced IENF density (P = .03). CONCLUSIONS: Small-fiber sensory and autonomic neuropathies constitute the major form of neuropathy in late-stage CKD. Furthermore, skin denervation was associated with the duration of renal disease.

Combined effects of repeated administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin and polychlorinated biphenyls on kidneys of male rats.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are persistent environmental contaminants that exist as complex mixtures in the environment, but the possible interactions of TCDD and PCBs have not been systematically investigated. The main objective of this study was to investigate the combined nephrotoxic effects of TCDD and PCBs on rats and to reveal the potential interactions between TCDD and PCBs. Male Sprague-Dawley rats were intragastrically administered TCDD (10 microg/kg), PCBs (Aroclor 1254, 10 mg/kg), or the combination (10 microg/kg TCDD + 10 mg/kg Aroclor 1254). After 12 consecutive days of exposure, all treatments induced nephrotoxicity, as evidenced by significant increases in the levels of serum creatinine and blood urea nitrogen, changes of kidney histopathology, and significant renal oxidative stress. Most of these effects were more remarkable in the combined-exposure group. Furthermore, all treatments induced renal cytochrome P450 1A1 (CYP1A1) protein expression, and the induction was more conspicuous in the combined-exposure group. These findings suggested that the nephrotoxicity induced by TCDD and PCBs in the present study might be attributable to the high expression of CYP1A1. In addition, the result of the two-way analysis of variance revealed that the combined effects of TCDD and PCBs were complicated, being additive, synergistic, or antagonistic depending on the selection of toxicity end points under the present experimental condition. This study demonstrates that combined exposure to TCDD and PCBs induced significant nephrotoxicity in rats, and there were complicated interactions between the two pollutants on the nephrotoxicity.

Repeated administration of a Fusarium mycotoxin butenolide to rats induces hepatic lipid peroxidation and antioxidant defense impairment.

Butenolide, a mycotoxin elaborated by several toxigenic Fusarium species, frequently contaminates important agricultural products, and has been considered a potential health risk to humans and animals. However, many toxicology issues including toxicity targets and mechanisms of butenolide remain unclear. Previous study indicated that acute butenolide exposure produced hepatic oxidative toxicity, but its chronic toxicity is still unknown. The present study therefore attempted to reveal the adverse effects of repeated butenolide exposure from a viewpoint of oxidative damage focusing on the liver. Intragastic administration of rats with butenolide for seven consecutive weeks resulted in hepatic injury as shown by obvious changes of serum biochemistry parameters indicating liver function. Repeated butenolide exposure also induced oxidative stress as manifested by impairment of antioxidant defenses including depletion of sulfhydryl groups and reduction of glutathione peroxidase activity, and enhancement of lipid peroxidation both in serum and liver. In conclusion, the present study indicated that repeated butenolide exposure induced a significant liver injury, and oxidative damage may serve as a mediator in the toxicity of butenolide. The current findings contribute to the understanding of the toxic profile of butenolide.

Basal expression of metallothionein suppresses butenolide-induced oxidative stress in liver homogenates in vitro.

Butenolide (4-acetamido-4-hydroxy-2-butenoic acid gamma-lactone) is a Fusarium mycotoxin which is frequently detected in foodstuffs and feedstuffs for human and animal consumption. It can evoke a broad spectrum of toxicities, thus posing a potential health risk to both humans and animals. Previous study showed that this mycotoxin produced a significant oxidative stress, and several antioxidants abated this effect. Metallothionein (MT) has been proposed as a potent antioxidant, therefore, this study attempts to determine whether endogenous expression of MT protects against butenolide-induced hepatic oxidative stress by using an in vitro incubation system of liver homogenates prepared from MT-I/II null (MT-/-) mice, and the corresponding wild type (MT+/+) mice. The results showed that butenolide elicited significant oxidative stress in both MT-/- mice and MT+/+ mice; however, MT-/- mice were more sensitive than MT+/+ mice to butenolide-induced hepatic oxidative stress, as evidenced by more production of thiobarbituric acid reactive substances and nitric oxide, and by more severe reductions of glutathione, superoxide dismutase and glutathione peroxidase in the liver homogenates of MT-/- mice than those of MT+/+ mice. These findings implicated the antioxidant potency of basal expression of MT in suppression of the oxidative stress of butenolide.

[Analysis of human normal prostate cells membrane proteins by shotgun-MS coupled with laser capture microdissection].

OBJECTIVE: To analyze of membrane proteins of human normal prostate epithelial cells. METHODS: Laser capture microdissection (LCM) technique was utilized to obtain the epithelial cells of human normal prostate. Shotgun-MS was used to generate protein profiles in the epithelial cells of human normal prostate. RESULTS: LCM technique successfully separated the normal prostate epithelial cells with homogeneity more than 95%. Under a stringent filter condition (charge +1, Xcorr >/= 1.9; charge +2, Xcorr >/= 2.2; charge +3, Xcorr >/= 3.75; DelCN >/= 0.1), 1164 proteins were identified in the human normal prostate cells, of which 799 had a gene ontology annotation (GOA) indicating a cellular component, others have no GOA terms. Among the GOA terms, 377 (49.15%) were known membrane proteins or membrane associated proteins. In addition to the proteins known to be associated with the membrane, a significant number of novel proteins had also been identified, including several hypothetical proteins and cDNA sequences. CONCLUSION: Shotgun-MS technique coupled with LCM effectively analyzes the proteins of human normal prostate cells, thus helping perfect the complete protein profiles of human normal prostate cells.

The oxidative damage of butenolide to isolated erythrocyte membranes.

Butenolide (CAS No. 16275-44-8), a mycotoxin produced by several Fusarium species, has been shown to be a potential risk factor for animal and human health. This study was undertaken to investigate the potential oxidative damage of butenolide to biomembranes in vitro using the erythrocyte membrane model. Following exposure of isolated rat erythrocyte membranes to butenolide, the extent of oxidative damage was assessed by measuring lipid peroxidation, -SH groups content, Ca2+/Mg2+-ATPase and Na+/K+-ATPase activities, and conformational changes in membrane proteins. It was observed that butenolide resulted in a significant lipid peroxidation, revealed by a concentration-dependent increase in the level of thiobarbituric acid reactive substances (TBARS). Similarly, this toxin induced a concentration-dependent decrease in the content of membrane total -SH groups, as well as free -SH groups. Membrane-bound enzymes were also impaired by the toxin, demonstrated by the marked inhibition of the activities of Na+/K+-ATPase and Ca2+/Mg2+-ATPase. Conformational changes in membrane proteins were determined using electron paramagnetic resonance (EPR) spin labeling. Butenolide caused an increase in the ratio of weakly to strongly immobilized components (W/S ratio) in a manner of concentration-dependent, indicating conformational changes in membrane proteins occurred. In conclusion, these findings indicate that butenolide is capable of inducing significant oxidative damage to membrane lipids and proteins.

Rhabdomyolysis following recent severe coxsackie virus infection in patient with chronic renal failure: one case report and a review of the literature.

Coxsackie virus infection may be life-threatening, although in most cases, it is asymptomatic. Coxsackie virus infection can cause rhabdomyolysis. This study reports a 39-year-old female patient with chronic renal failure who presented with fever, myalgia, anuria, edema, vomiting, diarrhea, exacerbation of renal function, elevation of serum CK, CK-MB, CK-MM, myoglobin, and liver function abnormality. Serology for Coxsackie virus IgM antibody was positive at first, and IgG antibody became positive 4 weeks later. Muscle biopsy showed skeletal muscle denaturalization and necrosis. She underwent hemodialysis three times per week and then kidney transplantation. No evidence suggests relapse of Coxsackie virus infection 5 months after transplantation. As illustrated with the present case, serological testing may reveal an early, quick, and simple diagnosis in a case of rhabdomyolysis after a viral illness.

Depletion of intracellular glutathione mediates butenolide-induced cytotoxicity in HepG2 cells.

Butenolide, 4-acetamido-4-hydroxy-2-butenoic acid gamma-lactone is one of the mycotoxins produced by Fusarium species which are often found on cereal grains and animal feeds throughout the world. It has been implicated as the etiology of some diseases both in animals and in humans. Though butenolide represents a potential threat to animal and human heath, there are few studies on its toxicity so far, especially on the toxic mechanisms. In this study, we investigated the cytotoxicity of butenolide on HepG2 cells and its possible mechanism from the viewpoint of oxidative stress. Butenolide reduced cell viability in a concentration- and time-dependent manner. A rapid depletion of intracellular glutathione (GSH) was observed after exposure cells to butenolide, concomitantly an increase in intracellular reactive oxygen species (ROS) production prior to cell death, indicating that oxidative stress was involved in butenolide cytotoxicity. To elucidate the role of GSH in the cytotoxicity of butenolide, intracellular GSH content was modulated before exposure to butenolide. l-buthionine-[S,R]-sulfoximine (BSO), a well-known inhibitor of GSH synthesis, aggravated butenolide-induced GSH depletion, ROS production and the loss in cell viability; in contrast, GSH depletion and ROS production was strongly inhibited, and the loss in cell viability was completely abrogated by thiol-containing compounds GSH, N-acetylcysteine (NAC) and dithiothreitol (DTT). Furthermore, a ROS scavenger catalase obviously abated ROS production and cytotoxicity induced by butenolide. Together, these results clearly demonstrate that oxidative stress plays an important role in butenolide cytotoxicity, and intracellular GSH depletion may be an original trigger of the onset of butenolide cytotoxicity.