英國研究人員最近發(fā)現(xiàn)了一些強(qiáng)有力的證據(jù)表明：吸食大麻會(huì)提高人體患癌癥的風(fēng)險(xiǎn)，破壞人體DNA,，改變DNA結(jié)構(gòu)。
據(jù)報(bào)道,，使用新開發(fā)的高度敏感的液體色譜法中的串聯(lián)質(zhì)譜法,，英國萊斯特大學(xué)的科學(xué)家們發(fā)現(xiàn)，在實(shí)驗(yàn)室條件下,，吸食大麻會(huì)損害DNA ,。此項(xiàng)研究結(jié)果發(fā)表在最新一期的《毒理學(xué)化學(xué)研究》雜志上,。
這項(xiàng)研究的參寫者包括拉吉德·辛格（Rajinder Singh）， 賈亭德帕·桑德（Jatinderpal Sandhu）,， 包文德·考爾 （Balvinder Kaur）,，蒂娜·仁（Tina Juren），威廉·彼·斯特瓦德（William P. Steward）,，丹·斯格巴克（DanSegerback）和彼得波·法莫（Peter B. Farmer）,，他們分別來自瑞典癌癥生物標(biāo)記和預(yù)防組、癌癥研究和分子醫(yī)學(xué)部門和卡羅林斯卡研究所,。
研究專家拉吉德·辛格說： “部分植物大麻,，也被稱為大麻或印度大麻，通常作為消遣性毒品吸食,，但它們?cè)谠S多國家吸食大麻是違法的 ,。” 目前為止，有許多有關(guān)煙草煙霧毒性的研究,。據(jù)悉,，煙草煙霧含有4000種化學(xué)物質(zhì)，其中60種被列為致癌物質(zhì),。相比之下,，有關(guān)大麻的研究不是很多。因?yàn)榇舐榈目扇夹詻]有煙草強(qiáng),，它們往往被摻雜在煙草里一起使用,。研究結(jié)果表明，大麻煙霧中包含400種化合物 ,，然而,，由于其較低的可燃性，它比煙草煙霧含有多50 ％以上的致癌多環(huán)芳烴,，包括萘,，苯并蒽和苯并芘。
有關(guān)這項(xiàng)研究的報(bào)告中提到,，隨著光譜測(cè)定法的改進(jìn),，越來越多的實(shí)驗(yàn)結(jié)果表明：吸食大麻會(huì)損害DNA。其中一位專家表示：“眾所周知,，煙草煙霧中的有毒物質(zhì)會(huì)損害DNA和增加患肺癌和其他癌癥的風(fēng)險(xiǎn),。科學(xué)家們以前不確定是否大麻煙霧也具有同樣的效果,。我們目前主要集中于研究乙醛的毒性,，因?yàn)闊煵莺痛舐橹卸己幸胰?rdquo;
研究人員還補(bǔ)充說：“大麻煙破壞DNA的能力更強(qiáng)，對(duì)人類健康的影響更大,，特別是當(dāng)吸食者吸大麻煙時(shí)比吸煙草煙更深入地吸入肺部,，從而增加了呼吸的負(fù)擔(dān),。一天吸食3到4根大麻煙對(duì)支氣管黏液膜的損害程度相當(dāng)于一天吸20根或更多煙草香煙的程度。”
研究人員研究后得出的結(jié)論,，為大麻損害人體DNA提供了充足的證 據(jù),，這也意味著吸食大麻煙危害人體健康，誘發(fā)癌癥,。（生物谷Bioon.com）
生物谷推薦原始出處：
Chem. Res. Toxicol., 2009, 22 (6), pp 1181–1188 DOI: 10.1021/tx900106y
Evaluation of the DNA Damaging Potential of Cannabis Cigarette Smoke by the Determination of Acetaldehyde Derived N2-Ethyl-2′-deoxyguanosine Adducts
Rajinder Singh*, Jatinderpal Sandhu?, Balvinder Kaur?, Tina Juren?, William P. Steward§, Dan Segerbck? and Peter B. Farmer?
Cancer Biomarkers and Prevention Group, Biocentre, Department of Cancer Studies and Molecular Medicine, University of Leicester, University Road, Leicester LE1 7RH, United Kingdom, Department of Biosciences and Nutrition, Unit of Molecular Epidemiology, Karolinska Institute, S-141 57 Huddinge, Sweden, and Cancer Biomarkers and Prevention Group, Department of Cancer Studies and Molecular Medicine, University of Leicester, Fifth Floor RKCSB, Leicester Royal Infirmary, Leicester, LE2 7LX United Kingdom
Acetaldehyde is an ubiquitous genotoxic compound that has been classified as a possible carcinogen to humans. It can react with DNA to form primarily a Schiff base N2-ethylidene-2′-deoxyguanosine (N2-ethylidene-dG) adduct. An online column-switching valve liquid chromatography tandem mass spectrometry (LC-MS/MS) selected reaction monitoring (SRM) method was developed for the determination of N2-ethylidene-dG adducts in DNA following reduction with sodium cyanoborohydride (NaBH3CN) to the chemically stable N2-ethyl-2′-deoxyguanosine (N2-ethyl-dG) adduct. Accurate quantitation of the adduct was obtained by the addition of the [15N5]N2-ethyl-dG stable isotope-labeled internal standard prior to enzymatic hydrolysis of the DNA samples to 2′-deoxynucleosides with the incorporation of NaBH3CN in the DNA hydrolysis buffer. The method required 50 μg of hydrolyzed DNA on column for the analysis, and the limit of detection for N2-ethyl-dG was 2.0 fmol. The analysis of calf thymus DNA treated in vitro with acetaldehyde (ranging from 0.5 to 100 mM) or with the smoke generated from 1, 5, and 10 cannabis cigarettes showed linear dose-dependent increases in the level of N2-ethyl-dG adducts (r = 0.954 and r = 0.999, respectively). Similar levels (332.8 ± 21.9 vs 348.4 ± 19.1 adducts per 108 2′-deoxynucleosides) of N2-ethyl-dG adducts were detected following the exposure of calf thymus DNA to 10 tobacco or 10 cannabis cigarettes. No significant difference was found in the levels of N2-ethyl-dG adducts in human lung DNA obtained from nonsmokers (n = 4) and smokers (n = 4) with the average level observed as 13.3 ± 0.7 adducts per 108 2′-deoxynucleosides. No N2-ethyl-dG adducts were detected in any of the DNA samples following analysis with the omission of NaBH3CN from the DNA hydrolysis buffer. In conclusion, these results provide evidence for the DNA damaging potential of cannabis smoke, implying that the consumption of cannabis cigarettes may be detrimental to human health with the possibility to initiate cancer development.
