Proliferation Inhibitory Activity of Quinones from Blaps rynchopetera Defense Secretion on Colorectal Tumor Cells / 中国结合医学杂志

OBJECTIVE@#To explore the proliferation inhibitory effect of quinones from Blaps rynchopetera defense secretion on colorectal tumor cell lines.@*METHODS@#Human colorectal cancer cell HT-29, human colorectal adenocarcinoma cell Caco-2 and normal human colon epithelial cell CCD841 were chosen for the evaluation of inhibitory activity of the main quinones of B. rynchopetera defense secretion, including methyl p-benzoquinone (MBQ), ethyl p-benzoquinone (EBQ), and methyl hydroquinone (MHQ), through methyl thiazolyl tetrazolium assay. The tumor-related factors, cell cycles, related gene expressions and protein levels were detected by enzyme-linked immunosorbent assy, flow cytometry, RT-polymerase chain reaction and Western blot, respectively.@*RESULTS@#MBQ, EBQ, and MHQ could significantly inhibit the proliferation of Caco-2, with half maximal inhibitory concentration (IC50) values of 7.04 ± 0.88, 10.92 ± 0.32, 9.35 ± 0.83, HT-29, with IC50 values of 14.90 ± 2.71, 20.50 ± 6.37, 13.90 ± 1.30, and CCD841, with IC50 values of 11.40 ± 0.68, 7.02 ± 0.44 and 7.83 ± 0.05 µg/mL, respectively. Tested quinones can reduce the expression of tumor-related factors tumor necrosis factor α, interleukin (IL)-10, and IL-6 in HT-29 cells, selectively promote apoptosis, and regulate the cell cycle which can reduce the proportion of cells in the G1 phase and increase the proportion of the S phase. Meanwhile, tested quinones could up-regulate mRNA and protein expression of GSK-3β and APC, while down-regulate that of β-catenin, Frizzled1, c-Myc, and CyclinD1 in the Wnt/β-catenin pathway of HT-29 cells.@*CONCLUSION@#Quinones from B. rynchopetera defense secretion could inhibit the proliferation of colorectal tumor cells and reduce the expression of related factors, which would be functioned by regulating cell cycle, selectively promoting apoptosis, and affecting Wnt/β-catenin pathway-related mRNA and protein expressions.

Involvement of HSP90 in ischemic postconditioning-induced cardioprotection by inhibition of the complement system, JNK and inflammation

Abstract Purpose To investigate whether heat shock protein 90 (HSP90) is involved in complement regulation in ischemic postconditioning (IPC). Methods The left coronary artery of rats underwent 30 min of occlusion, followed by 120 min of reperfusion and treatment with IPC via 3 cycles of 30s reperfusion and 30s occlusion. The rats were injected intraperitoneally with 1 mg/kg HSP90 inhibitor geldanamycin (GA) after anesthesia. Eighty rats were randomly divided into four groups: sham, ischemia-reperfusion (I/R), IPC and IPC + GA. Myocardial infarct size, apoptosis index and the expression of HSP90, C3, C5a, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1β and c-Jun N-terminal kinase (JNK) were assessed. Results Compared with the I/R injury, the IPC treatment significantly reduced infarct size, release of troponin T, creatine kinase-MB, and lactate dehydrogenase, and cardiomyocyte apoptosis. These beneficial effects were accompanied by a decrease in TNF-α, IL-1β, C3, C5a and JNK expression levels. However, all these effects were abrogated by administration of the HSP90 inhibitor GA. Conclusion HSP90 exerts a profound effect on IPC cardioprotection, and may be linked to the inhibition of the complement system and JNK, ultimately attenuating I/R-induced myocardial injury and apoptosis.

Effects of thymoquinone and curcumin on the regeneration of rat livers subject to 70% hepatectomy

Abstract Purpose: To investigate thymoquinone, curcumin and a combination of these two drugs were effective or not at the growth of liver. Methods: Forty female Wistar-Albino rats distributed into five groups of eight rats each, control, thymoquinone, curcumin, and thymoquinone/curcumin groups. Pathological specimens were studied using the Ki-67 Proliferation Index(PI); and arginase(Arg), tissue plasminogen activator(tPA), ceruloplasmin(Cer) and nitric oxide(NO) were studied in biochemical analysis. Results: Our results showed that Ki-67 proliferation index was low in Groups 1. The proliferation coefficient was significantly higher in the Group 2 and Group 4 than in the Group 1 and Group 3.(P < 0.001 between Groups 1 and 2, 1 and 4, and 3 and 4). There was no difference between Groups 2 and 4 (P = 1). The results of the biochemical Arg, tPA and Cer test showed statistically between the Group 1 and Group 2. NO showed significant differences Group 1 and 3. Conclusions: Thymoquinone and curcumin both have known positive effects on the organism. Histological and biochemical tests showed that thymoquinone is more effective than curcumin.

Thymoquinone reverses learning and memory impairments and brain tissue oxidative damage in hypothyroid juvenile rats / Timoquinona protegeu contra deficiências de aprendizagem e memória e danos nos tecidos cerebrais em ratos hipotireoidais juvenis

ABSTRACT In this study, the effect of thymoquinone (TQ) on propylthiouracil (PTU)-induced memory impairment was investigated in juvenile rats. The rats were grouped into control, Hypo, Hypo-TQ5 and Hypo-TQ10. Propylthiouracil increased latency time in the Morris water maze test and decreased delay in entering the dark compartment in the passive avoidance test. Both 5 mg/kg and 10 mg/kg doses of TQ decreased latency time in the Morris water maze test and increased delay in entering the dark compartment in a passive avoidance test. The PTU also increased malondialdehyde and nitric oxide metabolites in the brain while reduced the thiol content and superoxide dismutase and catalase activities and serum T4 level. Both doses of TQ decreased malondialdehyde and nitric oxide metabolites in the brain while enhanced the thiol content and superoxide dismutase and catalase activities and serum T4 level. The results of the present study showed that TQ protected against PTU-induced memory impairments in rats.

RESUMO Neste estudo, foi investigado o efeito da timoquinona (TQ) contra deficiências de memória induzidas por propiltiouracilo (PTU) em ratos juvenis. Os ratos foram agrupados em grupos: controle, Hypo, Hypo-TQ5, e Hypo-TQ10. O PTU aumentou o tempo de latência no teste do labirinto aquático de Morris (MWM) e diminuiu o atraso para entrar no compartimento escuro no teste de evasão passiva (PA). Ambas as doses de TQ diminuíram o tempo de latência no teste de MWM e aumentaram o atraso para entrar no compartimento escuro no teste de PA. O PTU também aumentou os metabolitos de malondialdeído (MDA) e óxido nítrico (NO) no cérebro, enquanto reduziu o teor de tiol e as atividades de superóxido dismutasa (SOD) e catalasa (CAT) e o nível sérico de T4. Ambas as doses de TQ diminuíram os metabolitos de MDA e de NO no cérebro, aumentaram o conteúdo de tiol e as atividades de SOD e CAT e o nível de T4 no soro. Os resultados do presente estudo mostraram que a TQ protegeu contra deficiências de memória induzidas por PTU em ratos.

Effects of thymoquinone against cisplatin-induced cardiac injury in rats

PURPOSE: T o investigate the possible protective effect of thymoquinone (TQ) in cisplatin (CP) induced myocardial injury. METHODS: A total of 28 adult male Wistar-Albino rats were randomly and equally divided into four groups as follows: Group 1 (control), Group 2 (CP at 15 mg/kg dose), Group 3 (TQ 40 mg/kg/day for two days prior to CP injection and on third day, CP at 15 mg/kg dose was intraperitoneally administered and TQ treatment continued until fifth day) and Group 4 (TQ at 40mg/kg/day dose for five days). RESULTS: There was a significant increment in CP group in terms of congestion, edema and pycnotic nuclei in myocardial fibers, comparing with other groups. TQ group exhibited significant increase in expression of antiapoptotic protein Bcl-2, comparing with CP group (p<0.05). In only CP administered group, expression of antiapoptotic protein Bcl-2 was lowest comparing with other groups. CONCLUSION: Established data indicate that cisplatin is cardiotoxic and thymoquinone may be useful in treating CP-induced cardiac injury.

Adherence to standard precautions from the standpoint of the Health Belief Model: the practice of recapping needles / Adesão às precauções padrão sob o prisma do Modelo de Crenças em Saúde: a prática de reencapar agulhas

The aim of this study was to applythe Health Belief Model to explain the adherence to the recommendation not to recap needles by dentists and dental assistants of the public health system in a municipality in the State of São Paulo. A questionnaire validated and adapted for the oral health area was used, which included variables related to the frequency of recapping and health beliefs using Likert-type scales. The relationship between beliefs and adherence to the recommendation not to recap needles was obtained by regression analysis. Of all the professionals in this study (n=79), the majority (83.5%) reported recapping needles at least once in the last month. Through regression analysis, it was observed that the relationship between the beliefs described by the model and the attitude whether or not to follow the recommendation not to recap needles was explained by a lower perception of psychological barriers and a greater perception of stimuli not to recap needles. The conclusion reached is that the acceptance of recommendations to prevent working accidents with biological material was explained by some dimensions of the Health Belief Model, enabling discussion about reformulation of training offered to professionals of the public health system.

Objetivou-se neste estudo aplicar o Modelo de Crenças em Saúde a fim de explicar a adesão à recomendação de não reencapar agulhas por cirurgiões-dentistas e auxiliares de saúde bucal da rede pública de um município paulista. Utilizou-se um questionário validado e adaptado para a área de saúde bucal, que contemplava variáveis relativas à frequência do reencape e crenças em saúde, por meio de escalas tipo Likert. A relação entre as crenças e a adesão à recomendação de não reencapar agulhas foi obtida por meio da análise de regressão. Da amostra de profissionais obtida por adesão ao estudo (n = 79), a maioria (83,5%) relatou ter reencapado agulhas pelo menos alguma vez no último mês. Por meio da análise de regressão, foi observado que a relação entre as crenças descritas pelo modelo e a atitude de aderir ou não à recomendação de não reencapar agulhas foi explicada por uma menor percepção de barreiras psicológicas e por uma maior percepção de estímulos para não reencapar agulhas. Conclui-se que a aceitação das recomendações para prevenir acidentes do trabalho com material biológico foi explicado por algumas dimensões do Modelo de Crenças em Saúde, possibilitando a discussão sobre a reformulação de capacitações oferecidas para profissionais do sistema público de saúde.

Effect of thymoquinone on ethanol and high fat diet induced chronic pancreatitis—a dose response study in rats.

A significant increase in serum lipase, amylase, capase-1 and myeloperoxidase activities, oxidative stress index (OSI), IL-1β and IL-18 was observed in rats receiving ethanol (EtOH) and high fat diet (HFD). Thymoquinone (TQ) supplementation along with EtOH and HFD significantly decreased the levels of serum lipase, amylase, capase-1, myeloperoxidase, OSI and maintained the antioxidant status when compared to untreated EtOH and HFD fed rats. Among the 4 doses, 100 mg of TQ/kg body weight was found to provide optimum protective effect on pancreas against EtOH and HFD induced abnormal changes. Histological observations added more evidence for the anti-inflammatory effect of TQ.

Effect of Pertussis Toxin and Herbimycin A on Proteinase-Activated Receptor 2-Mediated Cyclooxygenase 2 Expression in Helicobacter pylori-Infected Gastric Epithelial AGS Cells

Helicobacter pylori (H. pylori) is an important risk factor for chronic gastritis, peptic ulcer, and gastric cancer. Proteinase-activated receptor 2 (PAR2), subgroup of G-protein coupled receptor family, is highly expressed in gastric cancer, and chronic expression of cyclooxygenase-2 (COX-2) plays an important role in H. pylori-associated gastric carcinogenesis and inflammation. We previously demonstrated that H. pylori induced the expression of PAR2 and COX-2 in gastric epithelial cells. Present study aims to investigate whether COX-2 expression induced by H. pylori in Korean isolates is mediated by PAR2 via activation of Gi protein and Src kinase in gastric epithelial AGS cells. Results showed that H. pylori-induced COX-2 expression was inhibited in the cells transfected with antisense oligonucleotide for PAR2 or treated with Gi protein blocker pertussis toxin, Src kinase inhibitor herbimycin A and soybean trypsin inbitor, indicating that COX-2 expression is mediated by PAR2 through activation of Gi protein and Src kinase in gastric epithelial cells infected with H. pylori in Korean isolates. Thus, targeting the activation of PAR2 may be beneficial for prevention or treatment of gastric inflammation and carcinogenesis associated with H. pylori infection.

Protein tyrosine kinase inhibitors modify kainic acid-induced epileptiform activity and mossy fiber sprouting but do not protect against limbic cell death

Intrahippocampal administration of kainic acid (KA) induces synaptic release of neurotrophins, mainly brain-derived neurotrophic factor, which contributes to the acute neuronal excitation produced by the toxin. Two protein tyrosine kinase inhibitors, herbimycin A and K252a, were administered intracerebroventricularly, in a single dose, to attenuate neurotrophin signaling during the acute effects of KA, and their role in epileptogenesis was evaluated in adult, male Wistar rats weighing 250-300 g. The latency for the first Racine stage V seizure was 90 ± 8 min in saline controls (N = 4) which increased to 369 ± 71 and 322 ± 63 min in animals receiving herbimycin A (1.74 nmol, N = 4) and K252a (10 pmol, N = 4), respectively. Behavioral alterations were accompanied by diminished duration of EEG paroxysms in herbimycin A- and K252a-treated animals. Notwithstanding the reduction in seizure severity, cell death (60-90 percent of cell loss in KA-treated animals) in limbic regions was unchanged by herbimycin A and K252a. However, aberrant mossy fiber sprouting was significantly reduced in the ipsilateral dorsal hippocampus of K252a-treated animals. In this model of temporal lobe epilepsy, both protein kinase inhibitors diminished the acute epileptic activity triggered by KA and the ensuing morphological alterations in the dentate gyrus without diminishing cell loss. Our current data indicating that K252a, but not herbimycin, has an influence over KA-induced mossy fiber sprouting further suggest that protein tyrosine kinase receptors are not the only factors which control this plasticity. Further experiments are necessary to elucidate the exact signaling systems associated with this K252a effect.

Oxyradicals under UV-b stress and their quenching by antioxidants.

Formation of oxyradicals under UV-B stress was investigated using cucumber cotyledons. UV-B radiation induced production of free radicals which were analyzed by ESR spectroscopy. Evidence was obtained for the formation of superoxide and hydroxyl radicals in the tissues by comparing PBN-adducts formed with radicals obtained by chemical autooxidation of KO2 and Fenton's reaction. Addition of superoxide dismutase (SOD) to the reaction mixture partially reduced the intensity of signals confirming the production of superoxide radical as well as hydroxyl radicals. These radicals were quenched in vitro by the natural antioxidants alpha-tocopherol, ascorbic acid and benzoquinone. Changes in the level of antioxidants were also monitored under UV-B stress. The endogenous level of ascorbic acid was enhanced and alpha-tocopherol level was reduced in the tissue after exposure to UV-B radiation. The present report happens to be the first direct evidence obtained for the formation of superoxide and hydroxyl radicals in plant tissues exposed to UV-B radiation.

Thymoquinone reduces hepatic ischemia-reperfusion injury in rats

During liver surgery and liver transplantaion, ischemia-reperfusion [I/R] is an unavoidable and major unresolved problem. Therefore, various pharmacologic approaches to prevent hepatic I/R injury are currently under trial. In this study, thymoquinone [TQ], the active constituent of Nigella sativa seeds which has an antioxidant activity was investigated. Rats were classified into three groups. Group 1 served as control group [Sham operated]. In the 2[nd] and 3[rd] groups, the hepatic artery and portal vein were occluded. Rats in the 3[rd] group received TQ [50 mg/kg dissolved in corn oil orally] half an hour before occlusion. Asparatate aminotranferase [AST] and alanine aminotransferase [ALT] activities were measured in serum of blood samples taken from the canulataed carotid artery. Lipid peroxides content, superoxide dismutase [SOD] and DT-diaphorase activities were measured in liver homogenate. Pathological changes were assessed using hematoxylin and eosin [H and E] and periodic acid-Schiff [PAS] stains. There was marked elevation in the activities of serum AST and ALT in the non treated group compared to the control group, while in the treated group, there was significant decrease compared to the non-treated group. Also, in liver homogenate,;lipid peroxides content was significantly elevated in the non treated group [group 2] compared to the control group [group 1], while in the treated group [group 3], lipid peroxides content decreased significantly compared to the non-treated group [group 2]. SOD and DT-diaphorase were TQ treated group [3], there were significant increase compared to non-treated group [2]. The histopathological results showed dilation and hemorrhage in central vein and reduction in reaction of mucopolysachride in hepatocytes in non-treated group. These pathological changes significantly improved in TQ treated group [group 3]. The results suggest that thymoquinone is a beneficial protective agent against ischemia-reperfusion induced hepatic injury, an action that might be mediated through its antioxidant effect

The effect of thymoquinone on blood lipids in rats.

We have studied the effect of thymoquinone on the blood levels of cholesterol, triglycerides, HDL and LDL in albino rats. A total of 200 rats, 150 test group and 50 as controls, were included in the study. Six doses of thymoquinone (0.5, 1, 2, 4, 6, and 8 mg/kg/day) were given through intraperitonial injections at 8 Am. The drug was administered for 5 durations 1, 4, 7, 10, and 14 days. Thymoquinone produced significant reduction in the blood level of all parameters studied. There was no linear dose or time dependent effect on these parameters. The effect of thymoquinone started after 4 days with all doses and continued, with some swings, in the rest of the duration. The dose of 8 mg/kg was found to be toxic. It is concluded that thymoquinone has a hypocholestrolemic as well as a reducing effect on triglycrides, HDL and LDL. Therefore, we recommend further research on the therapeutic effect of thymoquinone in related diseases in humans and animals.

Effect of Nigella sativa L. and thymoquinone on rat platelet aggregation

The aim of the present study was to evaluate platelet responsiveness in rats following Nigella sativa L. [NS] and thymoquinone [TQ] administration. Additionally, the in vitro rat platelet aggregation response to TQ was investigated. Four doses of NS; 90, 180, 360 and 540 mg / Kg were fed daily to rats for 1, 2 and 4 weeks before running the aggregation study. TQ was administered as a single i. p. injection [4, 8, 12, 16 and; 20 mg /kg] 2-3 hours before testing the platelet response. Platelet rich plasma [PRP] was prepared from the treated rats, and platelet aggregation in response to collagen [10 micro,g / ml] and adenosine 5' - diphosphate [ADP; 20, 5 and 2.5 micro.M] was tested. Samples of 0.45 ml PRP from normal rats were also incubated with TQ [5, 10, 20, 50 micro.g] for 1 minute. Thereafter platelet aggregation response to collagen [10 micro g / ml] and ADP [20 micro.M] was performed by adding 0.05 ml of agonist [giving final concentrations of TQ 10, 20, 40, 100 micro,g / ml]. Platelet aggregation in response to collagen and ADP was not different in NS fed rats when compared with that in controls. Also tolerable doses of TQ [4 and 8 mg / Kg] and low concentration of TQ in vitro [10 micro.g / ml] neither affected collagen nor ADP induced platelet aggregation response. A dose of 12 mg TQ / Kg induced significant inhibition [p < 0.05] of platelet aggregation only when 2.5 micro.M of ADP was used for aggregation. Increasing TQ doses either in vivo or in vitro resulted in progressive inhibition of platelet aggregation. At a dose of 16 mg TQ / Kg there was significant inhibition by 25.1, 33.3, 74.7 and 75.7% with collagen and 20, 5 and 2.5 micro M ADP, respectively. The inhibition became more than 90% when 20 mg TQ / kg was administered. In vitro concentrations of TQ [20, 40 and 100 micro g / ml] caused significant inhibition of collagen and ADP [20 micro M]- induced aggregation by 37.8, 61.8,. 72% and 38.6, 83.1, 88.7%, respectively. These results suggest that regular consumption of NS would not influence platelet aggregation in humans. In the meantime, the findings show that TQ, NS major component, induces an inhibitory effect only when large doses are administered