Synergistic effects of piperine and curcumin in modulating benzo(a)pyrene induced redox imbalance in mice lungs

The objective of the present study was to evaluate the effects of curcumin alone and with adjuvant piperine against benzo(a)pyrene (BaP) induced oxidative stress in lungs of male Swiss albino mice. Mice were pretreated either with curcumin (100 mg/kg body weight), or piperine (20 mg/kg body weight), and in combination of both for one week, followed by single dose of benzo(a)pyrene (125 mg/kg body weight) treatment. Treatment with benzo(a)pyrene resulted in increased levels of lipid peroxides (LPO), protein carbonyl content (PCC) and with consequent decrease in the levels of tissue antioxidants like superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and reduced glutathione (GSH), which however, were increased significantly following curcumin treatment, but the increase was more pronounced when piperine was used as an adjuvant. BaP treatment alone did not alter significantly the GST activity. Pretreatment with curcumin increased the GST activity in BaP treated group, which was enhanced further upon synergistic treatment with piperine and curcumin. Therefore, combined administration of curcumin and piperine shall prove to be more effective in attenuating BaP induced toxicity.     

Combined effects of curcumin and piperine in ameliorating benzo(a)pyrene induced DNA damage

The present study was planned to investigate the antigenotoxic effects of curcumin and piperine separately and in combination against benzo(a)pyrene (BaP) induced DNA damage in lungs and livers of mice. Male Swiss albino mice received curcumin (100 mg kg⁻¹ body weight) and piperine (20 mg kg⁻¹ body weight) separately as well as in combination orally in corn oil for 7 days as pretreatments and subsequently, 2 h after, BaP was administered orally in corn oil (125 mg kg⁻¹ body weight). A single dose of BaP to normal mice increased the level of 8-oxo-2′-deoxyguanosine (8-oxo-dG) content and % DNA in the comet tail in the lungs and liver. Pretreatments of curcumin and curcumin plus piperine before administration of single dose of BaP significantly decreased the levels of 8-oxo-dG content and % DNA in the comet tail in both the tissues. Moreover, the genoprotective potential of curcumin plus piperine was significantly higher as compared to curcumin alone against BaP induced DNA damage.     

小鼠苯并(a)芘的急性免疫毒性

<正> 苯并(a)芘(B(a)P),是煤焦油、煤烟及其它燃料不完全燃烧的产物,不仅污染了人类的生产、生活环境,给人类健康带来严重危害,而且具有致癌作用。关于B(a)P ip的免疫毒性,国内外未见报道。本文观察了B(a)P对小鼠体液免疫、细胞免疫及巨噬细胞功能的影响。 材料与方法 LACA佰♀健康小鼠,8～10周龄,体重22～25g,由北京医科大学实验动物部提供。实验分200,100,50 mg/kg三组,同时设溶剂对照组,染毒途径为一次ip。B(a)P,Sigma和Fluka公司生产。溶于玉米油或橄榄油,在磁力搅拌器上避光搅拌4～6h,使     

Influence of estradiol on the benzo(a)pyrene hydroxylase activity induced by hexachlorocyclohexane

Basal BP-hydroxylase activity was measured in male Swiss mice from the age of 3 weeks to 20 months. Maximal enzyme activity was at the age of 5 months. Comparison of the inducibility of BP-hydroxylase by HCH was also investigated in male and female mice of different ages. Male mice showed higher induction of BP-hydroxylase by HCH than females of the same ages. Sterilization of female mice enhanced enzyme induction. Estradiol exhibited competitive inhibition of BP-hydroxylase activity. After treatment with HCH for 8 months, female mice had a lower tumour incidence than males, and this paralleled a lower induction of BP-hydroxylase.     

Chromosome aberrations induced by benzo(a)pyrene in a feeder cell-mediated assay

Studies were made on chromosome aberrations induced by benzo(a)pyrene (Bp) in V79 cells in the presence or absence of feeder cells. In the presence of feeder cells, chromosome aberrations at Bp concentrations of 1.0–20.0 μg/ml depended on feeder cell density. The highest incidences of chromosome aberrations (aberrant cells) and of aberrant chromosomes per 100 metaphase cells were 24.0% and 38.0%, respectively, and were obtained at 20.0 μg/ml Bp in the presence of 2.0 · 10⁶ feeder cells/60-mm plastic dish. In the absence of feeder cells, chromosome aberrations were not induced; the incidences of aberrant cells and chromosomes on treatment with Bp in the absence of a feeder layer were 3.0–5.0 and 3.0–6.0%, respectively, while the spontaneous rates (of both) were 5.0%.     

Mechanism of deltamethrin induced thymic and splenic toxicity in mice and its protection by piperine and curcumin: in vivo study

Deltamethrin (DLM) is a well-known pyrethroid insecticide which is widely used in the agriculture and home pest control due to restriction on the sale of organophosphate. DLM induced apoptosis is well known but its mechanism is still unclear. This study has been designed to find out its mechanism of apoptosis with the help of computational methods along with in vivo methods. The QikProp and ProTox results have shown that DLM has good oral absorption. The docking results reveal that DLM has a strong binding affinity toward the CD4, CD8, CD28 and CD45 receptors. Further, to understand the toxicity of DLM on lymphoid cells, a single dose of DLM (5?mg/kg, oral for seven days) has been administered to male Balb/c mice and cytotoxicity (MTT assay), oxidative stress indicators (glutathione, reactive oxygen species) and apoptotic markers (caspase-3 activity, DNA fragmentation) have been assessed in thymic and splenic single cell suspensions. Lowering of body weight, cellularity and loss in cell viability have been observed in DLM treated mice. The significant increase in ROS and GSH depletion in spleen and thymus, indicate the possible involvement of oxidative stress. The spleen cells appear more susceptible to the adverse effects of DLM than thymus cells. Further, for the amelioration of its effect, two structurally different bioactive herbal extracts, piperine and curcumin have been evaluated and have shown the cytoprotective effect by inhibiting the apoptogenic signaling pathways induced by DLM.     

Silymarin prevents the toxicity induced by benzo(a)pyrene in human erythrocytes by preserving its membrane integrity: An in vitro study

Silymarin, the purified extract from milk thistle Silybum marianum (L.) Gaertn, consists mainly of four isomeric flavonolignans: silibinin, isosilibinin, silidianin, and silichristin. The present study was carried out to evaluate the protective potential of silymarin in human erythrocytes against in vitro exposure to the carcinogen benzo(a)pyrene (B(a)P). Erythrocytes isolated from human blood were divided into four groups and treated with Vehicle [Group I], B(a)P (300 μM) [Group II], Silymarin (500 μM) + B(a)P (300 μM) [Group III], and Silymarin alone (500 μM)] [Group IV]. Silymarin treatment maintains the integrity of erythrocytes by preventing hemolysis, protein thiol oxidation and by decreasing the activity of AChE. SEM observations indicate that B(a)P induced significant alteration in the morphology of erythrocytes to echinocytes, which may be due to the interaction of B(a)P with the membrane's outer phopholipid monolayer. The light microscopic and SEM images show that silymarin treatment maintains the normal discocytic morphology of erythrocytes. The protective effect of silymarin might be attributed to its chemical structure and membranotrophic nature. The components silibinin, silydianin, and silychristin have OH in the 3rd, 5th, and 7th carbon atoms that may account for its increased antioxidant activity and removal of ROS formed during B(a)P metabolism. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 165–175, 2014.     

Prenatal induction of benzo(a)pyrene hydroxylases in mice

1. Benzo(a)pyrene hydroxylase (BPH) activity was measured in homogenates of fetal liver (day 18) or of whole-embryos of mice on day 9, 10 or 12 of gestation after maternal pretreatment with B(a)P on 3 consecutive days. A³H-liberation assay with³H-B(a)P labelled either generally or at the 6-position was used. The values obtained with the embryonic/fetal tissues were compared with those found in maternal liver. 2. Three oral doses of 17.5 mg B(a)P/kg body wt were found to just significantly induce BPH in maternal liver. An induction was observed after pretreatment with 24 mg B(a)P/kg body wt in 9-, 10-or 12-day-old whole-embryos, but the V_max reached was only 10–20% (1% on day 9) of that of adult non-induced liver. The K_m (6-hydroxylation) for all tissues tested were in the same range (600–900 nM). The induction was demonstrable in embryos at tissue levels about one order of magnitude lower than those required for induction in maternal liver. 3. Treatment with 25 mg B(a)P/kg body wt on 3 consecutive days was required to induce BPH in fetal liver on day 18 of gestation. The required B(a)P tissue concentrations were about one half of those necessary for induction in maternal liver. 4. Among a variety of other polycyclic hydrocarbons only chrysene showed an inducing potency similar to that of B(a)P in adult and fetal liver. For all compounds tested there was no correlation found in the inducing potency between adult and fetal liver (e.g. coronene). 5. The doses required to induce BPH in the maternal or fetal liver or in whole embryos of rodents are significantly higher (mg range) than those of usual average human exposure or those taken up by smokers (ng range).Abbreviations AHH aryl hydrocarbon hydroxylase - B(a)P benzo(a)pyrene - BPH benzo(a)pyrene hydroxylases - PAH polycyclic aromatic hydrocarbons     

Phytol ameliorated benzo(a)pyrene induced lung carcinogenesis in Swiss albino mice via inhibition of oxidative stress and apoptosis

In the present study, the modulatory effect of phytol against benzo(a)pyrene [B(a)P] induced lung carcinogenesis was investigated in Swiss albino mice. During the experimental period, phytol treatment showed no adverse toxic effect and mortality to the experimental animals. Lung tumor was observed in B(a)P treated group and also in animals post‐treated with low concentration (50 mg/kg) of phytol. No neoplastic changes were observed in the lung tissue of the animals treated with the maximum dose of phytol (100 mg/kg). An elevated level of antioxidant enzymes combined with macromolecular damage (lipid peroxidation, protein carbonyl content) was observed upon B(a)P treatment whereas, phytol restored the level of antioxidant enzymes which were comparable to the vehicle control group. Moreover, administration of B(a)P induced apoptosis, as observed by the highest expression of Bax, caspase‐3, and caspase‐9 proteins in lung tissue of B(a)P alone treated animals. However, phytol treatment reduced the expression of Bax, caspase‐3, and caspase‐9 protein and maintained the constant expression of anti‐apoptotic protein Bcl‐2. These observations positively reveal that phytol regulates the antioxidant enzymes and thereby protects the cells against B(a)P induced carcinogenesis without showing any adverse toxic effect to the animals.     

A toxicokinetic study to elucidate 3‐hydroxybenzo(a)pyrene atypical urinary excretion profile following intravenous injection of benzo(a)pyrene in rats

The toxicokinetics of benzo(a)pyrene (BaP) and 3‐hydroxybenzo(a)pyrene (3‐OHBaP) were assessed in 36 male Sprague–Dawley rats injected intravenously with 40 µmol kg¹ of BaP to explain the reported atypical urinary excretion profile of 3‐OHBaP. Blood, liver, kidney, lung, adipose tissue, skin, urine and feces were collected at t = 2, 4, 8, 16, 24, 33, 48, 72 h post‐dosing. BaP and 3‐OHBaP were measured by high‐performance liquid chromatography/fluorescence. A biexponential elimination of BaP was observed in blood, liver, skin and kidney (t_½ of 4.2–6.1 h and 12.3–14.9 h for initial and terminal phases, respectively), while a monoexponential elimination was found in adipose tissue and lung (t_½ of 31.2 and 31.5 h, respectively). A biexponential elimination of 3‐OHBaP was apparent in blood, liver and skin (t_½ of 7.3–11.7 h and 15.6–17.8 h for initial and terminal phases, respectively), contrary to adipose tissue, lung and kidney. In adipose tissue and lung, a monophasic elimination of 3‐OHBaP was observed (t_½ of 27.0 h and 24.1 h, respectively). In kidney, 3‐OHBaP kinetics showed a distinct pattern with an initial buildup during the first 8 h post‐dosing followed by a gradual elimination (t_½ of 15.6 h). In the 72‐h post‐treatment, 0.21 ± 0.09% (mean ± SD) of dose was excreted as 3‐OHBaP in urine and 12.9 ± 1.0% in feces while total BaP in feces represented 0.40 ± 0.16% of dose. This study allowed the identification of the kidney as a retention compartment governing 3‐OHBaP atypical urinary excretion. Copyright © 2010 John Wiley & Sons, Ltd.     

Protective effect of Diosmin against benzo(a)pyrene‐induced lung injury in Swiss Albino Mice

Diosmin, a naturally occurring flavonoid commonly present in citrus fruit, is known to exhibit anti‐inflammatory, antimutagenic, antioxidant, and free radical scavenging as well as blood lipid lowering activities among others. Diosmin has also been used for the treatment of various diseases including diabetes mellitus and Alzheimer's disease. Our study explores the role of Diosmin in pulmonary toxicity (lung injury) induced by environmental contaminant benzo(a)pyrene [B(a)P]. Swiss Albino Mice (SAM) were administered with either Diosmin 100 or 200 mg/kg body weight daily for 14 days and then challenged with a single dose of B(a)P. On the 15th day, animals were sacrificed; lung tissues and blood were collected for molecular analysis. B(a)P administration in mice induced the thickening of lung epithelium, damaged alveolar architecture, and promoted inflammatory cell infiltration in the lung tissues. Also, B[a]P significantly increased the expression of NF‐kB, COX‐2, IL‐6, Bax, cleaved caspase 3, and cleaved PARP proteins and decreased antioxidant enzyme levels. Diosmin‐100 and Diosmin‐200 significantly attenuated the damage to lung epithelium, alveolar architecture, and reduced inflammatory cell infiltration in the lung tissues of mice. Diosmin significantly (P < .05) attenuated the levels of oxidative stress markers: lactate dehydrogenase and xanthine oxidase. A decrease in expression of NF‐kB, COX‐2, IL‐6, Bax, cleaved caspase 3, and cleaved PARP proteins in mice was challenged with B[a]P. Diosmin thus could be a promising therapeutic adjuvant against B[a]P‐induced oxidative stress and lung damage.     

Assessment of alteration of reproductive system in vivo induced by subchronic exposure to benzo(a)pyrene via oral administration

The objective of this study was to assess whether subchronic exposure to benzo(a)pyrene (BaP) via oral ingestion alter endpoints of the reproductive system of mice. Hsd: ICR (CD1) 10‐week‐old males (n = 8) were randomly assigned to the exposure group and control group. Mice were administered BaP for 30 and 60 days by daily gavage at doses of 1, 10, 50, and 100 mg/kg body weight per day. At the end of the experiments, mice were anesthetized and reproductive organs, including testes, seminal vesicles, prostate, and cauda epididymis, were removed and examined. Spermatozoa quality and DNA strand breaks were assessed—1 and 10 mg/kg/day of BaP for 30 and 60 days did not significantly induce altered morphology or weights of testes, prostate, seminal vesicle, and epididymis, and spermatozoa quality of mice; 100 mg/kg/day of BaP for 60 days decreased weights of testes, seminal vesicle, and cauda epididymis. BaP exposure also significantly decreased motility, normal head morphology, vitality, and concentration of mature spermatozoa. In addition, BaP exposure induced a significant increase in DNA strand breaks. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 1–8, 2015.     

Induction of hepatocellular carcinoma in rat liver by initial treatment with benzo(a)pyrene after partial hepatectomy and promotion by phenobarbital

The hepatocarcinogenicity of benzo(a)pyrene(BP) in the rat was examined. Rats were treated with BP after partial hepatectomy and then kept on a diet containing phenobarbital (PB) as a promoter. Tumors including a hepatocellular carcinoma developed in the rat liver by week 52.     

Molecular cloning of CYP1A gene and its expression by benzo(a)pyrene from goldfish (Carassius auratus)

We cloned and sequenced the cytochrome P450 1A (CYP1A) gene from goldfish (Carassius auratus). It has a 1581 bp open reading frame that encodes a 526 amino acid protein with a theoretical molecular weight of 59.02 kDa. The CYP1A amino acid sequence clusters in a monophyletic group with other fish CYP1As, and more closely related to zebrafish CYP1A (91% identity) than to other fish CYP1As. Exposure to benzo(a)pyrene (BaP) by intraperitoneal injection increased biliary BaP metabolites and liver CYP1A gene expression. BaP exposure also increased CYP1A gene expression in extrahepatic organs, including intestine, and gill, which are sensitive to aqueous and dietary exposure to Arylhydrocarbon receptor (AhR) agonists. Therefore, goldfish CYP1A identified in this study offers basic information for further research related to biomarker use of CYP1A of goldfish.     

苯并(a)芘引起鼠胸腺细胞DNA损伤及其机制

目的研究苯并(a)芘引起的鼠胸腺细胞DNA损伤及其机制。方法在加或不加代谢活化系统(S9)条件下,运用单细胞凝胶电泳技术检测不同浓度苯并(a)芘所致的鼠胸腺细胞DNA损伤,同时观察抗氧化剂N-乙酰-L-半胱氨酸对其损伤的影响;采用比色法测定不同浓度苯并(a)芘染毒后鼠胸腺细胞NO含量。结果10-4、10-5和10-6mol/L苯并(a)芘( S9)染毒后,鼠胸腺细胞DNA迁移距离分别为(42.14±5.23)(、25.36±2.96)和(18.78±1.72)μm,与溶剂对照组(11.25±0.92)μm相比,差异有显著性,阳性组加入抗氧化剂N-乙酰-L-半胱氨酸后DNA迁移距离明显缩短;而鼠胸腺细胞NO含量并无显著增加。结论苯并(a)芘可引起鼠胸腺细胞DNA损伤,其损伤与苯并(a)芘代谢产生的活性氧有关,而NO可能不参其损伤。     

Effect of benzo(a)pyrene exposure on fluoranthene metabolism by mouse adipose tissue microsomes

The present study has been undertaken to examine whether exposure to benzo(a)pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH) compound, influences the metabolism of fluoranthene (FLA), another PAH compound. Microsomes were isolated from the adipose tissue of mice that received 50?μg/kg BaP and incubated with FLA (3?µM) alone; FLA in combination with BaP at equimolar concentrations, and a control group that received nothing. Post-incubation, samples were extracted with ethyl acetate and analyzed for FLA metabolites by reverse-phase HPLC with fluorescence detection. The rate of FLA metabolism (pmol of metabolite/min/mg protein) was increased when microsomes from BaP-treated mice were exposed to FLA alone and FLA in combination with BaP, compared to controls. On the other hand, the difference in FLA metabolic rate between microsomes that were exposed to FLA + BaP was higher than the ones that received FLA. The microsomes from BaP-pre-treated mice produced a considerably higher proportion of FLA 2, 3-diol, and 2, 3 D FLA when microsomes were incubated with FLA. There were no differences in the FLA metabolite types formed when BaP-pre-treated mice were co-incubated with BaP and FLA than with FLA alone. The enhanced biotransformation of FLA as a result of prior and concomitant exposure to BaP may have implications for assessment of risks arising from human exposure to PAH mixtures.     

Comparative metabolism of benzo(a)pyrene by ovarian microsomes of various species

Knowledge of the ability of the female reproductive system to metabolize polycyclic aromatic hydrocarbons (PAHs) is critical to the diagnosis and management of female infertility and for risk assessment purposes. The PAHs are a family of widespread pollutants that are released into the environment from automobile exhausts, cigarette smoke, burning of refuse, industrial emissions, and hazardous waste sites. In exposed animals, PAHs become activated to reactive metabolites that interfere with target organ function and as a consequence cause toxicity. The extent of susceptibility to PAH exposure may depend on the ability of animals to metabolize these chemicals. The present study has been undertaken to assess whether any differences exist among mammals in the metabolism of benzo(a)pyrene (BaP), a prototypical PAH compound. Microsomes isolated from the liver and ovaries of rats, mice, goats, sheep, pigs, and cows were incubated with 5 μM BaP. Postincubation, samples were extracted with ethyl acetate and analyzed for BaP/metabolites by reverse‐phase HPLC with fluorescence detection. The rate of metabolism (pmol of metabolite/min/mg protein) was found to be more in liver than in ovary in all the species studied (P < 0.05). The differences in metabolite concentrations were statistically significant (P < 0.0001) among the various species in both organs studied. Multiple species comparison also revealed that the differences were statistically significant (P < 0.001) between rodents (rat and mouse) and higher mammals (ewe, sow, and cow). Even among the higher mammals, in a majority of the cases, the differences in metabolite concentrations were significantly different (P < 0.001) both in ovary and liver. The BaP metabolites identified were 4,5‐diol; 7,8‐diol; 9,10‐diol; 3‐hydroxy BaP; and 9‐hydroxy BaP. The rodent microsomes produced considerably higher proportion of BaP 4,5‐diol and 9,10‐diol than did cow, sow, goat, and sheep. However, microsomes from higher mammals converted a greater proportion of BaP to 3‐hydroxy and 9‐hydroxy BaP, the detoxification products of BaP. Overall, our results revealed a great variation among species to metabolize BaP. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.     

Protective effects of lemongrass essential oil against benzo(a)pyrene-induced oxidative stress and DNA damage in human embryonic lung fibroblast cells

Benzo(a)pyrene (BaP) was a well-known environmental pollutant, numerous studies had implicated BaP as a causative agent in human cancer, particularly lung cancer. The lemongrass essential oil (LEO) possessed various pharmacological activities, especially the anti-oxidative stress and cancer prevention. In the current study, human embryonic lung fibroblast (HELF) cells were treated with 25?mM BaP in the absence or presence of 0.5%, 1% or 2.5% LEO and the cell viability and levels of oxidative stress (OS) and DNA damage in the cells were then measured. Nineteen chemical constituents were identified in LEO, with citral being the main component, representing about 68.78%. LEO was able to protect the HELF cells against BaP-induced loss in cell viability, achieving a maximum of 95.58% cell viability at the 0.5% concentration. Treatment of HELF cells with BaP alone significantly increased the level of Malondialdehyde (MDA) and decreased superoxide dismutase (SOD) and catalase (CAT). However, these effects were suppressed when the cells were also treated with LEO, leading to enhanced levels of SOD and CAT activities (2.9- and 2-fold, respectively, compared with BaP treatment only) and reduced the level of MDA in the cells (43% reduction in malondialdehyde level). At the same time, LEO also reduced the level of DNA damage, as shown by a reduced level of 8-hydroxy-deoxyguanosine (8-OHdG). Taken together, the results showed that LEO offered protection against BaP-induced OS and DNA damage, suggesting that LEO could be a promising agent for lung cancer chemoprevention.