Hematological Parameters and the State of Liver Cells of Rats After Oral Administration of Aflatoxin B1 Alone and Together with Nanodiamonds
© The Author(s) 2010
Received: 5 November 2009
Accepted: 26 February 2010
Published: 14 March 2010
Hematological parameters and the state of liver cells of rats were examined in vivo after the animals received aflatoxin B1 (AfB1) alone and together with modified nanodiamonds (MND) synthesized by detonation. The rats that had received the MND hydrosol had elevated leukocyte levels, mainly due to higher granulocyte counts and somewhat increased monocyte counts compared to control rats. Hematological parameters of the rats that had received AfB1 alone differed from those of the control rats in another way: total white blood cell counts were significantly lower due to the decreased lymphocyte counts. In rats that had consumed AfB1 with the MND hydrosol, changes in hematological parameters were less pronounced than in rats that had consumed either AfB1 or MND. Electron microscopy showed that hepatocytes of the rats that had received the MND hydrosol or AfB1 with the MND hydrosol contained elevated levels of lipid inclusions and lysosomes. Hyperplasia of the smooth endoplasmic reticulum (EPR) was revealed in liver specimens of the rats that had received AfB1. Results of the study suggest the conclusion about mutual mitigation of the effects of nanoparticles and the mycotoxin on rats blood and liver cells after AfB1 has adsorbed on MND.
Aflatoxins are secondary metabolites produced by Aspergillus —a widely occurring genus of mold fungi. Food and feed products infested by mold fungi can be contaminated with aflatoxins. This is a serious hazard to animal and human health, as aflatoxins are mutagenic and carcinogenic. Aflatoxin B1 (AfB1) is the most hazardous mycotoxin in this group, and there is no threshold concentration for its toxic effect. The main target of AfB1 is liver and it undergoes transformations in hepatocytes: biotransformation to active AfB1-8,9-epoxide, which gets bound with DNA; irreversible hydroxylation, forming metabolites M1, P1, and Q1; reversible hydroxylation, forming aflatoxicol [1–5]. Aflatoxins that come into animal and human gastrointestinal systems with contaminated food can be mitigated by various enterosorbents [6–9].
Modified nanodiamonds (MND) synthesized by detonation can be proposed as intestinal adsorbent of mycotoxins. A highly developed MND surface, as well as the presence of various chemically active functional groups, hydrocarbon fragments, and metal microimpurities on the surface of nanoparticles, determines their high affinity for sorption of biomolecules [10–12]. Some physicochemical properties of the nanodiamond surface are presented in the work of Gibson et al. . MND have good colloidal stability in dispersion media and are adapted for biological and medical studies. Thus, MND hydrosols can be used for all kinds of injections and oral administration of nanoparticles to animals in long-duration experiments. We proved in animal experiments that MND are highly biocompatible . Low toxicity of nanodiamonds was reported by A. Schrand et al. .
In this study, we examined the effect of AfB1 on hematological parameters and the state of liver cells of rats that orally received AfB1 alone and together with MND.
Experiments were conducted on adult Wistar rats, which were kept in a vivarium, under similar conditions. The rats were randomly divided into 4 groups (3 animals per group). Every rat was kept in its own cage. Animals of the control (Group 1) drank water. Animals of the treatment groups drank an MND hydrosol containing 0.4 wt% nanoparticles (Group 2), an aqueous solution of AfB1 (Group 3), an MND hydrosol (0.4 wt%) containing AfB1 (Group 4). Every rat of groups 3 and 4 received the amount of the liquid proportional to its body mass. Thus, the total amounts of AfB1 per 1 g weight orally received by the rats were equal for all animals of these groups. After the rats had consumed the AfB1-containing liquids for 10 days, they received water (Group 3) or MND hydrosol (Group 4) within approximately 25 days. This 25-day period was used for a more complete manifestation of the cumulative effect of the AfB1 in animals. The total duration of the experiment was 35 days.
AfB1 used in this study was analytical grade and supplied by «Ecolan» (Russia) as the standard for HPLC. One ampoule contained 10 μg mycotoxin dissolved in 1 mL acetonitrile. Aqueous AfB1 solution was prepared by substituting distilled water for acetonitrile.
Preparation of MND and MND with AfB1
MND of 4- to 250-nm grade (Brand RUDDM 0–0.25) produced by detonation in “Real-Dzerzhinsk” Ltd. (Russia) were used in the experiments. The MND hydrosol (0.4 wt%) was prepared by adding distilled water to nanoparticle powder. The AfB1-containing MND hydrosol was prepared by adding a mycotoxin aqueous solution to the nanoparticle hydrosol. The amounts of free AfB1 and AfB1 bound with nanoparticles were determined by spectral analysis. For this purpose, after adding AfB1 aqueous solution to the MND hydrosol samples, they were stirred in a Vortex-Genie 2 g-560E (Scientific Industries, Inc., USA) for 10 s and incubated for 2 min at room temperature, and the particles were then collected by centrifugation (Centrifuge 5415R, Eppendorf, Germany) at 14,100g for 10 min. The ability of nanoparticles to coagulate was used for their more complete removal. For this purpose, the specimens were supplemented with NaCl at a concentration of 80–100 mM before centrifugation. The supernatants obtained were assessed by spectral analysis in the range of 200–500 nm at an UVIKON-943 UV/VIS spectrophotometer (Kontron Instruments, Italy).
Hematological and Electron Microscopic Analyses
After the end of the experiment, we took samples of blood from the animals for hematological analysis. Hematological parameters were evaluated using an ABX MICROS-60 hematology analyzer (France). Then the rats were killed, in compliance with the euthanasia principles, and liver samples were taken for transmission electron microscopic (TEM) examination. Liver tissue samples were fixed in 2.5% glutaraldehyde in 0.1 M cacodylate buffer at pH 7.2; then they were additionally fixed in a 1% OsO4 solution in the same buffer. The samples were dehydrated in graded series of ethanol and in acetone; then they were embedded in Epon 812-Araldite M epoxy resin mixture (“Serva”). Ultrathin sections were cut using a Reichert Um-03 ultramicrotome (Austria) and stained with a 3% of uranil acetate in 30% ethanol solution and 0.2% aqueous solution of lead citrate and examined in the JEM 1400 (JEOL, Japan).
The data were statistically processed by Microsoft Excel 2003 software. The confidence level was α = 0.05.
Results and Discussion
Thus, results of the examination of hematological parameters of blood and the state of the rats liver cells can suggest that oral administration of AfB1 together with the MND hydrosol produces a less toxic effect on animals than oral administration of AfB1 alone. After AfB1 has been adsorbed on MND, the effects of the mycotoxin and nanoparticles should be mutually mitigated. Our previous, in vitro, experiments proved that MND can adsorb AfB1 from aqueous solutions with subacid, acid, and alkaline pH, which are characteristic of different sections of the gastrointestinal system . Another advantage of MND as intestinal adsorbent is the high rate of AfB1 adsorption (the process taking not more than 2–3 min) and very good biocompatibility of nanoparticles, proven by in vivo experiments with animals of various species . Hence, MND can be proposed as intestinal adsorbent to bind and neutralize mycotoxins, AfB1 in particular.
The study was financially supported by the Russian Foundation for Basic Research (RFBR) (Grant No. 06-04-90234) and the RAS Presidium (Program No. 27, Project No. 64).
This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.
- Gorelick NJ: Risk assessment for aflatoxin: I. Metabolism of aflatoxin B1 by different species. Risk Anal. 1990, 10: 539. COI number [1:STN:280:DyaK3M7kt1GhtA%3D%3D] COI number [1:STN:280:DyaK3M7kt1GhtA%3D%3D] 10.1111/j.1539-6924.1990.tb00538.xView ArticleGoogle Scholar
- Bennett JW, Klich M: Mycotoxins. Clin. Microbiol. Rev. 2003, 16: 497. COI number [1:CAS:528:DC%2BD3sXmsV2qtL4%3D] COI number [1:CAS:528:DC%2BD3sXmsV2qtL4%3D] 10.1128/CMR.16.3.497-516.2003View ArticleGoogle Scholar
- Murphy PA, Hendrich S, Landgren C, Bryant CM: Food mycotoxins: an update. J. Food Sci. 2006, 71: R51. COI number [1:CAS:528:DC%2BD28Xms1ajsr0%3D] COI number [1:CAS:528:DC%2BD28Xms1ajsr0%3D] 10.1111/j.1750-3841.2006.00052.xView ArticleGoogle Scholar
- Richard JL: Some major mycotoxins and their mycotoxicoses—an overview. Int. J. Food Microbiol. 2007, 119: 3. COI number [1:CAS:528:DC%2BD2sXht12gtbnM] COI number [1:CAS:528:DC%2BD2sXht12gtbnM] 10.1016/j.ijfoodmicro.2007.07.019View ArticleGoogle Scholar
- Castells M, Marin S, Sanchis V, Ramos AJ: Distribution of fumonisins and aflatoxins in corn fractions during industrial cornflake processing. Int. J. Food Microbiol. 2008, 123: 81. COI number [1:CAS:528:DC%2BD1cXjtVChs7Y%3D] COI number [1:CAS:528:DC%2BD1cXjtVChs7Y%3D] 10.1016/j.ijfoodmicro.2007.12.001View ArticleGoogle Scholar
- Diaz DE, Hagler WM, Hopkins BA, Whitlow LW: Aflatoxin binders I: in vitro binding assay for aflatoxin B1 by several potential sequestering agents. Mycopathologia 2002, 156: 223. 10.1023/A:1023388321713View ArticleGoogle Scholar
- Aly SE, Abdel-Galil MM, Abdel-Wahhab MA: Application of adsorbent agents technology in the removal of aflatoxin B1 and fumonisin B1 from malt extract. Food Chem. Toxicol. 2004, 42: 1825. COI number [1:CAS:528:DC%2BD2cXntlGgtLk%3D] COI number [1:CAS:528:DC%2BD2cXntlGgtLk%3D] 10.1016/j.fct.2004.06.014View ArticleGoogle Scholar
- Desheng Q, Fan L, Yanhu Y, Niya Z: Adsorption of aflatoxin B1 on montmorillonite. Poult. Sci. 2005, 84: 959. COI number [1:CAS:528:DC%2BD2MXlt1CiurY%3D] COI number [1:CAS:528:DC%2BD2MXlt1CiurY%3D]View ArticleGoogle Scholar
- Phillips TD, Afriyie-Gyawu E, Williams J, Huebner H, Ankrah NA, Ofori-Adjei D, Jolly P, Johnson N, Taylor J, Marroquin-Cardona A, Xu L, Tang L, Wang J-S: Reducing human exposure to aflatoxin through the use of clay: a review. Food. Addit. Contam. Part A 2008, 25: 134. COI number [1:CAS:528:DC%2BD1cXitFKhs7s%3D] COI number [1:CAS:528:DC%2BD1cXitFKhs7s%3D] 10.1080/02652030701567467View ArticleGoogle Scholar
- Bondar VS, Puzyr AP: Nanodiamonds for biological investigations. Phys. Solid State 2004, 46: 716. COI number [1:CAS:528:DC%2BD2cXjtF2lurc%3D]; Bibcode number [2004PhSS...46..716B] COI number [1:CAS:528:DC%2BD2cXjtF2lurc%3D]; Bibcode number [2004PhSS...46..716B] 10.1134/1.1711457View ArticleGoogle Scholar
- Puzyr AP, Purtov KV, Shenderova OA, Luo M, Brenner DW, Bondar VS: The adsorption of aflatoxin B1 by detonation-synthesis nanodiamonds. Dokl. Biochem. Biophys. 2007, 417: 299. COI number [1:CAS:528:DC%2BD1cXlsVWn] COI number [1:CAS:528:DC%2BD1cXlsVWn] 10.1134/S1607672907060026View ArticleGoogle Scholar
- Purtov KV, Burakova LP, Puzyr AP, Bondar VS: The interaction of linear and ring forms of DNA molecules with nanodiamonds synthesized by detonation. Nanotechnology 2008, 19: 1. 10.1088/0957-4484/19/32/325101View ArticleGoogle Scholar
- Gibson N, Shenderova O, Luo TJM, Moseenkov S, Bondar V, Puzyr A, Purtov K, Fitzgerald Z, Brenner DW: Colloidal stability of modified nanodiamond particles. Diam. Relat. Mater. 2009, 18: 620. COI number [1:CAS:528:DC%2BD1MXitFKnt7w%3D] COI number [1:CAS:528:DC%2BD1MXitFKnt7w%3D] 10.1016/j.diamond.2008.10.049View ArticleGoogle Scholar
- Puzyr AP, Baron AV, Purtov KV, Bortnikov EV, Skobelev NN, Mogilnaya OA, Bondar VS: Nanodiamonds with novel properties: a biological study. Diam. Relat. Mater. 2007, 16: 2124. COI number [1:CAS:528:DC%2BD2sXhtlGmt7fL] COI number [1:CAS:528:DC%2BD2sXhtlGmt7fL] 10.1016/j.diamond.2007.07.025View ArticleGoogle Scholar
- Schrand AM, Huang H, Carlson C, Schlager JJ, Osawa E, Hussain SM, Dai L: Are diamond nanoparticles cytotoxic? J. Phys. Chem. B 2007, 111: 2. COI number [1:CAS:528:DC%2BD28XhtlSrsrrE] COI number [1:CAS:528:DC%2BD28XhtlSrsrrE] 10.1021/jp066387vView ArticleGoogle Scholar
- Hengstler JG, Van Der Burg B, Steinberg P, Oesch F: Interspecies differences in cancer susceptibility and toxicity. Drug Metab. Rev. 1999, 31: 917. COI number [1:CAS:528:DyaK1MXnvFCitrY%3D] COI number [1:CAS:528:DyaK1MXnvFCitrY%3D] 10.1081/DMR-100101946View ArticleGoogle Scholar
- Puzyr AP, Bondar VS, Selimkhanova ZYu, Inzhevatkin EV, EV Bortnikov: Results of studies of application of detonation nanodiamonds as enterosorbents. Sib. Med. Rev 2004, 25: 2–3.Google Scholar
- Reddy RV, Taylor MJ, Sharma RP: Studies of immune function of CD-1 mice exposed to aflatoxin B1. Toxicology 1987, 43: 123. COI number [1:CAS:528:DyaL2sXhslSltb0%3D] COI number [1:CAS:528:DyaL2sXhslSltb0%3D] 10.1016/0300-483X(87)90002-3View ArticleGoogle Scholar
- Raisuddin S, Singh KP, Zaidi SI, Saxena AK, Ray PK: Effects of aflatoxin on lymphoid cells of weanling rat. J. Appl. Toxicol. 1990, 10: 245. COI number [1:CAS:528:DyaK3cXlt1Oru7c%3D] COI number [1:CAS:528:DyaK3cXlt1Oru7c%3D] 10.1002/jat.2550100404View ArticleGoogle Scholar
- Hinton DM, Myers MJ, Raybourne RA, Francke-Carroll S, Sotomayor RE, Shaddock J, Warbritton A, Chou MW: Immunotoxicity of aflatoxin B1 in rats: effects on lymphocytes and the inflammatory response in a chronic intermittent dosing study. Toxicol. Sci. 2003, 73: 362. COI number [1:CAS:528:DC%2BD3sXktVCnsr8%3D] COI number [1:CAS:528:DC%2BD3sXktVCnsr8%3D] 10.1093/toxsci/kfg074View ArticleGoogle Scholar
- Imaoka S, Ikemoto S, Shimada T, Funae Y: Mutagenic activation of aflatoxin B1 by pulmonary, renal, and hepatic cytochrome P450s from rats. Mutat. Res. 1992, 269: 231. COI number [1:CAS:528:DyaK3sXit1Kr] COI number [1:CAS:528:DyaK3sXit1Kr]View ArticleGoogle Scholar
- Guengerich FP: Cytochrome P450 and chemical toxicology. Chem. Res. Toxicol. 2008, 21: 70. COI number [1:CAS:528:DC%2BD2sXhtlynurbF] COI number [1:CAS:528:DC%2BD2sXhtlynurbF] 10.1021/tx700079zView ArticleGoogle Scholar
- Zhaksilikova AK: Ultrastructural changes of liver after cadmium intoxication and Tagan-sorbent correction. Bull. Sib. Branch Russ. Acad. Med. Sci. 2005, 115: 66.Google Scholar