Involvement of Nrf2, JAK and COX pathways in acetaminophen-induced nephropathy: Role of some antioxidants

ObjectivesAcetaminophen (APAP)-induced nephrotoxicity is detrimental consequence for which there has not been a standardized therapeutic regimen. Although, N-acetylcysteine (NAC) is a well-known antidote used in APAP-induced hepatotoxicity, its benefit in nephrotoxicity caused by APAP is almost lacking. This study aimed to compare the possible protective effect of thymoquinone (TQ), curcumin (CR), and α-lipoic acid (α-LA), either in solo or in combination regimens with that of NAC against APAP-induced renal injury.Design and methodRats were divided into nine groups; control group, APAP intoxicated group (1000 mg/kg; orally), and the remaining seven groups received, in addition to APAP, oral doses of NAC, TQ, CR, α-LA, CR plus TQ, TQ plus α-LA, or CR plus α-LA. The first dose of the aforementioned antioxidants was given 24 h before APAP, and then the second dose was given 2 h after APAP, whereas the last dose was given 10 h after administration of APAP.ResultsTreatment with APAP elevated kidney markers like serum uric acid, urea, and creatinine. In addition, it increased the serum level of tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β) and thiobarbituric acid reactive species (TBARS). Also, the protein expression of renal janus kinase (JAK) and cyclooxygenase (COX)-2 were all upregulated by APAP. In contrast, the expression of Nrf2 and the renal levels of superoxide dismutase and glutathione were downregulated. Treatment with the indicated natural antioxidants resulted in amelioration of the aberrated parameters through exhibiting anti-inflammatory, antioxidant and free radical-scavenging effects with a variable degree.ConclusionThe combined administration of CR and TQ exerted the most potent protection against APAP-induced nephrotoxicity through its anti-inflammatory and free radical-scavenging effects (antioxidant) which were comparable to that of NAC-treatment.     

Evaluation of the effect of terpenoid quinones on Trichophyton mentagrophytes by solution and vapor contact

The antimicrobial activity against two bacterial strains and three fungi of five terpenoid quinones, three related quinones, and a quinone-containing essential oil was investigated by broth dilution and by agar vapor and box vapor assays. All the quinones, except for coenzyme Q₁₀, exhibited their highest activity against Trichophyton mentagrophytes. Thymoquinone showed the most potent activity, not only by solution contact but also by vapor contact, with menadione the next most potent. Alizarin showed high activity only by solution contact. The antibacterial activity was related to the orthoquinone structure (1,2-chloranil and 1,2-naphthoquinone) and the antifungal activity was related to the paraquinone structure (chloranil, ubiquinone 0, thymoquinone, and menadione).     

Thymoquinone (2-Isopropyl-5-methyl-1, 4-benzoquinone) as a chemopreventive/anticancer agent: Chemistry and biological effects

Cancer remains the topmost disorder of the mankind and number of cases is unceasingly growing at unprecedented rates. Although the synthetic anti-cancer compounds still hold the largest market in the modern treatment of cancer, natural agents have always been tried and tested for potential anti-cancer properties. Thymoquinone (TQ), a monoterpene and main ingredient in the essential oil of Nigella sativa L. has got very eminent rankings in the traditional systems of medicine for its anti-cancer pharmacological properties. In this review we summarized the diverse aspects of TQ including its chemistry, biosynthesis, sources and pharmacological properties with a major concern being attributed to its anti-cancer efficacies. The role of TQ in different aspects involved in the pathogenesis of cancer like inflammation, angiogenesis, apoptosis, cell cycle regulation, proliferation, invasion and migration have been described. The mechanism of action of TQ in different cancer types has been briefly accounted. Other safety and toxicological aspects and some combination therapies involving TQ have also been touched. A detailed literature search was carried out using various online search engines like google scholar and pubmed regarding the available research and review accounts on thymoquinone upto may 2019. All the articles reporting significant addition to the activities of thymoquinone were selected. Additional information was acquired from ethno botanical literature focusing on thymoquinone. The compound has been the centre of attention for a long time period and researched regularly in quite considerable numbers for its various physicochemical, medicinal, biological and pharmacological perspectives. Thymoquinone is studied for various chemical and pharmacological activities and demonstrated promising anti-cancer potential. The reviewed reports confirmed the strong anti-cancer efficacy of thymoquinone. Further in-vitro and in-vivo research is strongly warranted regarding the complete exploration of thymoquinone in ethnopharmacological context.     

百里醌对血管生成及胰腺癌生长的影响

目的: 探讨百里醌对血管生成和胰腺癌生长的影响及其机制。方法: 采用贴壁选择法培养人脐血内皮祖细胞(EPCs),细胞免疫组化检验细胞中血管内皮生长因子受体-2(VEGFR-2)、VIII因子和 CD34表达,证实细胞属性;观察不同浓度(10 nmol/L、20 nmol/L和40 nmol/L)百里醌对EPCs小管形成的影响;不同浓度(20 μmol/L、40 μmol/L和80 μmol/L)百里醌作用人胰腺癌细胞株PANC-1后,Western blotting检测胰腺癌细胞中血管内皮生长因子(VEGF)表达的变化;建立裸鼠胰腺癌原位移植瘤模型,分成对照组和百里醌组,实验结束后观察百里醌对裸鼠胰腺癌生长的抑制作用;免疫组织化学法检测裸鼠胰腺肿瘤组织中Ki-67、CD34和VEGF的阳性表达。结果: 体外成功培养出人脐血EPCs,百里醌可显著抑制体外EPCs小管形成;并抑制体外人胰腺癌PANC-1细胞中VEGF的表达;与对照组相比较,百里醌可明显抑制荷瘤裸鼠中胰腺肿瘤生长,并下调Ki-67、CD34和VEGF在胰腺肿瘤组织中的阳性表达。结论: 百里醌可抑制体内外血管生长,有望作为治疗胰腺癌的血管抑制药物。     

An Evaluation of the Protective Effects of Thymoquinone on Amikacin-Induced Ototoxicity in Rats

Objectives

In this study we investigated the probable protective effects of thymoquinone on amikacin-induced ototoxicity in rats.

Methods

Thirty-two healthy rats were divided into four groups (amikacin, amikacin+thymoquinone, thymoquinone, and no treatment). Thymoquinone was fed to the rats via oral gavage in a dose of 40 mg/kg/day throughout the study period of 14 days. Amikacin was given by the intramuscular route in a dose of 600 mg/kg/day. Audiological assessment was conducted by the distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) tests, administered to all rats at the beginning of the study, and also on days 7 and 15. Biochemical parameters were calculated at the termination of the study to evaluate the oxidative status.

Results

There were significant decreases in DPOAE values and significant increases in ABR thresholds of the amikacin group on days 7 and 15, as compared to the amikacin+thymoquinone group. While ABR thresholds of the amikacin group increased significantly on days 7 and 15 as compared to their initial values, there were no significant differences between the initial and the 7th and 15th day values of ABR thresholds in the amikacin+thymoquinone group. Total oxidant status and oxidative stress index values of the amikacin+thymoquinone group were significantly lower than those of the amikacin group. Total antioxidant status values of the amikacin+thymoquinone group were significantly higher than those of the amikacin group.

Conclusion

Our study has demonstrated that the ototoxic effect brought forth by amikacin could be overcome with the concurrent use of thymoquinone.     

Gastroprotective activity of Nigella sativa L oil and its constituent, thymoquinone against acute alcohol-induced gastric mucosal injury in rats

AIM: To evaluate the role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effect of Nigella sativa L oil (NS) and its constituent thymoquinone (TQ) in an experimental model. METHODS: Male Wistar albino rats were assigned into 4 groups. Control group was given physiologic saline orally (10 mL/kg body weight) as the vehicle (gavage); ethanol group was administrated 1 mL (per rat) absolute alcohol by gavage; the third and fourth groups were given NS (10 ml/kg body weight) and TQ (10 mg/kg body weight p.o) respectively 1 h prior to alcohol intake. One hour after ethanol administration, stomach tissues were excised for macroscopic examination and biochemical analysis. RESULTS: NS and TQ could protect gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. NS prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. NS also increased gastric glutathione content (GSH), enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, TQ protected against the ulcerating effect of alcohol and mitigated most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than NS. Neither NS nor TQ affected catalase activity in gastric tissue. CONCLUSION: Both NS and TQ, particularly NS can partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects might be induced, at least partly by their radical scavenging activity.     

Thymoquinone Augments Cyclophosphamide-Mediated Inhibition of Cell Proliferation in Breast Cancer Cells

Objective: Cancer chemotherapy at the recommended doses is largely associated with toxicity, and also it is noteffective enough to reduce the advancement of the disease at lower doses. Thymoquinone (TQ) is an active compoundderived from black seeds (Nigella sativa) which exhibits anticancer activities. The aim of the present study was toinvestigate the synergistic effect of TQ alone and in combination with cyclophosphamide (cyclo), and to unravel therole of TQ in fatty acid synthase (FASN) mediated molecular signaling in Her2 + and Her2- breast cancer cell lines.Methods: The effect of TQ on the growth of Her2+ SKBR-3 and Her2- MDA-231 breast cancer lines were evaluatedas percent cell viability by cytotoxicity-based MTT assay. The analysis of cell cycle arrest was done through flowcytometryfollowed by Western blot and RT-PCR to detect signaling events in the cells. Results: The data showedthat TQ-cyclo (0.5mM-10μM) combination significantly inhibited the proliferation through the 5.49% and 57.72%accumulation of cells in sub-G1 and G1 respectively as 12% cells were shifted from G2/M phase in Her2+ breast cancercells. Similarly, TQ-cyclo (0.5mM-20μM) combination exhibited that the 16.6% cells were arrested in Sub-G1 and only3.54% cells were remained in G2/M phase as it was 22.89% in DMSO control in Her-2- breast cancers cells. ThoughTQ alone or in combination with cyclo alleviated the PI3K/Akt signaling by downregulating the phosphorylation of Aktand upregulating the PTEN, no changes was observed in FASN and Her-2 as well in both type of cells. The significantdecreased expression of cyclin D1 was found in TQ-cyclo combinations. Conclusion: The current findings suggestedthat TQ can alter the cell cycle progression and induce cell death independent of FASN mediated signaling. In terms ofclinical perspective, the present study clearly showed that TQ can broadly augment the effect of cyclo in breast cancercases irrespective of Her-2+ or Her-.     

百里醌抑制人胰腺癌BxPC-3细胞体外运动和侵袭的研究

背景:胰腺癌是恶性程度最高的消化道肿瘤,目前吉西他滨依赖的化疗对抑制胰腺癌转移的治疗效果欠佳。研究发现百里醌对多种肿瘤细胞具有抑制增殖、促进凋亡的作用。目的:探讨百里醌对人胰腺癌BxP C-3细胞体外运动和侵袭的影响及其作用机制。方法:常规培养人胰腺癌细胞株BxP C-3,加入不同浓度百里醌进行处理。采用Boyden小室法检测细胞体外运动、侵袭情况;蛋白质印迹法检测细胞FAK、Akt蛋白表达和Akt磷酸化水平的改变;免疫荧光技术检测细胞内FAK表达、细胞黏着斑和F-actin的变化。结果:10、25μmol/L百里醌对BxP C-3细胞体外运动的抑制率分别为43.4%、73.8%,对体外侵袭的抑制率分别为60.5%、75.6%,百里醌呈浓度依赖性地抑制胰腺癌BxP C-3细胞的体外运动、侵袭(P0.05)。百里醌能明显下调BxP C-3细胞FAK表达,并抑制细胞磷酸化Akt的激活。百里醌可诱导FAK弥散分布于胞质,明显抑制黏着斑形成和F-actin的聚合集化。结论:百里醌通过抑制FAK/PI3K/Akt通路的信号转导和激酶活性,浓度依赖性地抑制人胰腺癌BxP C-3细胞的体外运动和侵袭。     

Thymoquinone effectively alleviates lung fibrosis induced by paraquat herbicide through down-regulation of pro-fibrotic genes and inhibition of oxidative stress

The potential preventive and therapeutic effects of thymoquinone (TQ) and its molecular mechanism were evaluated in paraquat (PQ)-induced pulmonary fibrosis in mice. TQ was administered orally at the doses of 20 and 40 mg/kg during the course and after development of fibrosis. Pathological changes, expressions of genes involved in fibrogenesis, hydroxyproline (HP) and oxidative stress parameters were determined in the lung tissues. TQ dose-dependently recovered the pathological changes induced by PQ. TQ decreased hydroxyproline content, lipid peroxidation and restored the antioxidant enzymes to the normal values. In molecular level, expressions of TGF-β1, α-SMA, collagen 1a1 and collagen 4a1 genes were also returned to the control level by TQ. This study indicated that TQ has the preventive and therapeutic potentials for the treatment of lung fibrosis by inhibition of oxidative stress and down-regulation of profibrotic genes.     

Thymoquinone-induced relaxation of isolated rat pulmonary artery

Aim of the study

The effect of thymoquinone (TQ), the main constituent of the volatile oil of black seed (Nigella sativa L. family Ranunculaceae), on the isolated rat pulmonary arterial rings was investigated.

Materials and methods

Isolated rat pulmonary arterial rings were precontracted with phenylephrine and concentration–response curves to TQ were constructed. The effects of different receptors antagonists or enzyme inhibitors were examined.

Results

TQ caused a concentration-dependent decrease in the tension of the pulmonary arterial rings precontracted by phenylephrine. The effects of TQ were not influenced by pretreatment of the rings with propranolol (a non-selective β-blocker), atropine (a non-selective blocker for muscarinic receptors), theophylline (an adenosine receptor antagonist), indomethacin (a cyclooxygenase inhibitor), L-NAME (a NO synthase inhibitor), methylene blue (an inhibitor of soluble guanylyl cyclase) and nifedipine (a Ca²⁺ channel blocker). The effects of TQ were significantly potentiated by bosentan (an ET_A/ET_B receptor antagonist). The effects of TQ were slightly abolished by pretreatment of the rings with glibenclamide (a non-selective blocker of ATP-sensitive K+ channels). TQ totally abolished the pressor effects of serotonin and phenylephrine on the isolated rat pulmonary arterial rings.

Conclusion

The results of the present study suggest that TQ-induced relaxation of the precontracted pulmonary artery is probably mediated, at least in part, by activation of ATP-sensitive potassium channels and possibly by non-competitive blocking of serotonin, α1 and endothelin receptors.