Effect of Topical Application of Black Seed Oil on Imiquimod‐Induced Psoriasis‐like Lesions in the Thin Skin of Adult Male Albino Rats

Psoriasis is a chronic inflammatory skin disease that affects about 1%–3% of the world's population. Black seed oil, i.e., the oil extracted from black seeds (Nigella sativa seeds), possesses a broad spectrum of pharmacological actions including anti‐inflammatory, immunostimulatory, and antioxidant properties. This study aimed to investigate the effect of black seed oil on imiquimod (IMQ) induced psoriasis‐like skin lesions. To this end, 30 male albino rats were divided into three groups: group I, control group; group II, psoriasis‐induced group receiving daily topical applications of IMQ cream (5%) on the shaved back skin for 10 consecutive days; and group III, black seed oil group receiving a daily topical dose of black seed oil 5 mg/kg body weight for 10 days after induction of psoriasis. Animals of all groups were sacrificed and specimens obtained from the skin of the central part of the back were processed for histological and immunohistochemical staining with proliferating cell nuclear antigen (PCNA). IMQ application led to epidermal inflammation, hyperplasia and alterations in the normal appearance of keratinocytes with degenerative changes observed at both light and electron microscopic levels. Collagenous fibers were abundant in the dermis and PCNA‐positive cells were detected in all layers of the epidermis. However, topical use of black seed oil strongly inhibited IMQ‐induced psoriasis‐like inflammation and alleviated all epidermal and dermal changes observed after IMQ application, allowing us to conclude that black seed oil can be used as an adjuvant topical therapy for treating psoriasis. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:166–174, 2018. © 2017 Wiley Periodicals, Inc.     

Chemical dispersants can suppress the activity of natural oil-degrading microorganisms

During the Deepwater Horizon oil well blowout in the Gulf of Mexico, the application of 7 million liters of chemical dispersants aimed to stimulate microbial crude oil degradation by increasing the bioavailability of oil compounds. However, the effects of dispersants on oil biodegradation rates are debated. In laboratory experiments, we simulated environmental conditions comparable to the hydrocarbon-rich, 1,100 m deep plume that formed during the Deepwater Horizon discharge. The presence of dispersant significantly altered the microbial community composition through selection for potential dispersant-degrading Colwellia, which also bloomed in situ in Gulf deep waters during the discharge. In contrast, oil addition to deepwater samples in the absence of dispersant stimulated growth of natural hydrocarbon-degrading Marinobacter. In these deepwater microcosm experiments, dispersants did not enhance heterotrophic microbial activity or hydrocarbon oxidation rates. An experiment with surface seawater from an anthropogenically derived oil slick corroborated the deepwater microcosm results as inhibition of hydrocarbon turnover was observed in the presence of dispersants, suggesting that the microcosm findings are broadly applicable across marine habitats. Extrapolating this comprehensive dataset to real world scenarios questions whether dispersants stimulate microbial oil degradation in deep ocean waters and instead highlights that dispersants can exert a negative effect on microbial hydrocarbon degradation rates.Crude oil enters marine environments through geophysical processes at natural hydrocarbon seeps (1) at a global rate of ∼700 million liters per year (2). In areas of natural hydrocarbon seepage, such as the Gulf of Mexico (hereafter, the Gulf), exposure of indigenous microbial communities to oil and gas fluxes can select for microbial populations that use petroleum-derived hydrocarbons as carbon and energy sources (3, 4). The uncontrolled deep-water oil well blowout that followed the explosion and sinking of the Deepwater Horizon (DWH) drilling rig in 2010 released about 750 million liters of oil into the Gulf. Seven million liters of chemical dispersants were applied (5) with the goal of dispersing hydrocarbons and stimulating oil biodegradation. A deep-water (1,000–1,300 m) plume, enriched in hydrocarbons (6–11) and dioctyl sodium sulfosuccinate (DOSS) (12, 13), a major component of chemical dispersants (14), formed early in the discharge (7). The chemistry of the hydrocarbon plume significantly altered the microbial community (11, 15–17), driving rapid enrichment of low-abundance bacterial taxa such as Oceanospirillum, Cycloclasticus, and Colwellia (18). The natural hydrocarbon degraders in Gulf waters were either in low abundance or absent in DWH deep-water plume samples (18).Chemical dispersants emulsify surface oil slicks, reduce oil delivery to shorelines (19), and increase dissolved oil concentrations, which should make oil more bioavailable (20) and stimulate biodegradation (21). The efficacy of dispersants in stimulating oil biodegradation is debated (22) and negative environmental effects have been documented (23). Dispersant application often requires ecological tradeoffs (24). Surprisingly little is known about the impacts of dispersants on the activity and abundance of hydrocarbon-degrading microorganisms (25). This work addressed three key questions: (i) Do dispersants influence microbial community composition? (ii) Is the indigenous microbial community as effective at oil biodegradation as microbial populations following dispersant/dispersed oil exposure? (iii) Does chemically dispersed oil stimulate hydrocarbon biodegradation rates?Laboratory experiments were used to unravel the effects of oil-only (supplied as a water-accommodated fraction, “WAF”), Corexit 9500 (“dispersant-only”), oil–Corexit 9500 mixture (chemically enhanced water-accommodated fraction, CEWAF) or a CEWAF with nutrients (CEWAF + nutrients) (SI Appendix) on Gulf deep-water microbial populations (SI Appendix, SI Text and Figs. S1 and S2). Experimental conditions (SI Appendix, Table S1) mimicked those prevailing in the DWH deep-water hydrocarbon plume (6–13, 18), the chemistry of which varied substantially over space and time (18). Amending samples with WAFs and CEWAFs assured that observed differences in microbial community composition and activity would be driven by compositional differences (e.g., the presence or absence of dispersants) in the dissolved organic carbon (DOC) pool rather than by differences in the bulk DOC concentration (26, 27). We developed an improved radiotracer method to directly quantify hydrocarbon oxidation rates. The microbial community composition was monitored over time using 16S rRNA amplicon sequencing. Dispersant application selected for specific microbial taxa and oligotypes with 16S rRNA gene sequences similar to those recovered in situ during the DWH discharge. Surprisingly, CEWAF (± nutrients) addition did not enhance microbial activity or microbial oil-degradation rates.     

From the Cover: Contribution of cyanobacterial alkane production to the ocean hydrocarbon cycle

Hydrocarbons are ubiquitous in the ocean, where alkanes such as pentadecane and heptadecane can be found even in waters minimally polluted with crude oil. Populations of hydrocarbon-degrading bacteria, which are responsible for the turnover of these compounds, are also found throughout marine systems, including in unpolluted waters. These observations suggest the existence of an unknown and widespread source of hydrocarbons in the oceans. Here, we report that strains of the two most abundant marine cyanobacteria, Prochlorococcus and Synechococcus, produce and accumulate hydrocarbons, predominantly C15 and C17 alkanes, between 0.022 and 0.368% of dry cell weight. Based on global population sizes and turnover rates, we estimate that these species have the capacity to produce 2–540 pg alkanes per mL per day, which translates into a global ocean yield of ∼308–771 million tons of hydrocarbons annually. We also demonstrate that both obligate and facultative marine hydrocarbon-degrading bacteria can consume cyanobacterial alkanes, which likely prevents these hydrocarbons from accumulating in the environment. Our findings implicate cyanobacteria and hydrocarbon degraders as key players in a notable internal hydrocarbon cycle within the upper ocean, where alkanes are continually produced and subsequently consumed within days. Furthermore we show that cyanobacterial alkane production is likely sufficient to sustain populations of hydrocarbon-degrading bacteria, whose abundances can rapidly expand upon localized release of crude oil from natural seepage and human activities.Hydrocarbons are ubiquitous in the oceans, where natural seepage and human activities are estimated to release between 0.4 and 4.0 million tons of crude oil into the ocean ecosystem annually (1). Even in minimally polluted marine surface waters, alkanes such as pentadecane and heptadecane have been found at concentrations ranging from 2 to 130 pg/mL (2, 3), although their sources remain unclear. A small proportion of alkanes, from 1 to 60 fg/mL, is associated with particulate matter >0.7 µm in diameter (4). Larger amounts may be associated with particulate matter <0.7 µm in diameter, because ocean concentrations are higher than the solubility of pentadecane and heptadecane, which is ∼10 pg/mL and 1 pg/mL, respectively (2). Populations of hydrocarbon-degrading bacteria, referred to as hydrocarbonoclastic bacteria, including many species that cannot use other carbon sources, are present in marine systems and play an important role in turnover of these compounds (5–9). Because obligate hydrocarbon-degrading bacteria are found in waters without significant levels of crude oil pollution, these organisms must use an alternate hydrocarbon source (9–11).Here, we investigate the extent to which cyanobacteria may contribute to these marine hydrocarbon pools. Cyanobacteria (oxygenic photosynthetic bacteria) can synthesize C15 to C19 hydrocarbons via two separate pathways. The first produces alkanes, predominantly pentadecane, heptadecane, and methyl-heptadecane, in addition to smaller amounts of alkenes, via acyl-ACP reductase (FAR) and aldehyde deformylating oxygenase (FAD) enzymes (12). The second pathway generates alkenes, primarily nonadecene and 1,14-nonadecadiene, via a polyketide synthase enzyme (Ols) (13). The abundance and ubiquity of cyanobacteria in the marine environment suggests hydrocarbon production in the oceans could be considerable and broadly distributed geographically (14, 15).We focused our studies on the two most abundant marine cyanobacteria, Prochlorococcus and Synechococcus (16). These genera have estimated global population sizes of 2.9 ± 0.1 × 10²⁷ and 7.0 ± 0.3 × 10²⁶ cells, respectively (14), and are together responsible for approximately a quarter of marine net primary production (14). These are also the only cyanobacterial genera for which global population size estimates have been compiled (14). Although the distribution patterns of both genera overlap (14, 17), Prochlorococcus cells dominate low-nutrient open-ocean areas between 40°N and 40°S and can be found at depths of up to 200 m (16, 18). Synechococcus are more numerous in coastal and temperate regions where conditions and nutrient levels are more variable (14, 16) but are still widely distributed in high abundance.     

经肝动脉灌注血管抑素治疗肝癌的研究

目的为了分析血管抑素基因经肝动脉灌注后抑制肝癌的作用。方法将制作成功的Wistar大鼠肝癌模型随机分成4组,分别给予血管抑素基因、超液态碘油、血管抑素基因 碘油200μL质粒和脂质体复合物(含20μg质粒),对照组则组予0.9%生理盐水200μl。结果所有的治疗组均有一定的治疗效果,但基因与碘油相比差异并不显著。而基因 碘油的治疗效果明显好于其他各组。结论基因联合碘油可以明显提高抑制肝癌生长和转移的作用。     

细辛挥发油抗过敏性鼻炎有效成分及靶点预测的研究

目的:采用血清药物化学-血清药理学与网络药理学方法,预测细辛挥发油抗过敏性鼻炎的有效成分及潜在靶点。方法:36只Wistar大鼠随机分为空白组、细辛挥发油0.5,1 h组(3 g·kg~(-1)生药量)、盐酸西替利嗪片1 h组(10 mg·kg~(-1))、醋酸泼尼松片1 h组(12 mg·kg~(-1))和辛芩颗粒1 h组(15 g·kg~(-1)),每组6只。灌胃后腹主动脉采血,血样3 000 r·min~(-1)离心10 min,无菌分离血清,-20℃冷冻保存。酶联免疫吸附测定法(ELISA)测定各时间点含药血清(血清容积10%)对抗原刺激1.5 h后大鼠嗜碱性细胞白血病细胞株(RBL-2H3)细胞(细胞密度2.5×105/m L)释放组胺、氨基己糖苷酶的影响(n=6);采用气相色谱-质谱联用(GC-MS)技术检测各时间点含药血清中的成分,比较细辛挥发油、灌胃0.5,1 h后含药血清和空白血清的色谱图,寻找细辛挥发油的移行成分;对移行成分进行靶点预测,构建和分析其"成分-靶点"网络。结果:与空白血清组相比,细辛挥发油0.5,1 h含药血清组均能抑制抗原诱导RBL-2H3肥大细胞释放组胺和脱颗粒(P0.05)。含药血清中检测到12个移行成分,分别为α-蒎烯,莰烯,2-β-蒎烯,δ-3-蒈烯,柠檬油精,1,8-桉叶素,优香芹酮,龙脑,3,5-二甲氧基甲苯,黄樟脑,甲基丁香酚,2,3,5-三甲氧基甲苯,它们可能通过调控环氧合酶-2,毒蕈碱乙酰胆碱受体M3,alpha 1肾上腺素能受体,一氧化氮合酶等靶点发挥抗过敏性鼻炎的作用。结论:该方法初步揭示细辛挥发油抗过敏性鼻炎的有效成分及其潜在靶点。     

月见草油脂肪酸钠盐影响家兔实验性动脉粥样硬化的病理形态学观察

为进一步探讨月见草油脂肪酸钠盐对家兔实验性动脉粥样硬化的影响，我们将１６只家兔分３组；实验对照组、预防服药组和空白对照组。前二组动物均饲胆固醇，预防服药组同时加饲月见草油脂肪酸钠盐，所有动物均饲等量基本饲料。１５０天后处死动物，在光学显微镜和电子显微镜下观察主动脉壁形态，并测算内膜动脉粥样硬化斑块面积等。结果发现，预防服药组动物主动粥样硬化斑块面积等。结果发现，预防服药组动物主动脉粥样硬化病变程度     

假益智果实挥发油成分分析及其抑菌活性

目的:对假益智果实挥发油进行化学成分研究,并进行抗菌活性测试,为进一步研究开发假益智提供实验依据。方法:使用水蒸气蒸馏法从假益智的果实中提取出挥发油,运用气相色谱-质谱(GC-MS)联用技术进行分析;使用微量稀释法测试挥发油的抗菌活性。结果:假益智果实挥发油提取率为0.17%,检测到42个化合物,鉴定出31个,占挥发油总成分的94.18%。挥发油对四联球菌具有很好的抑菌作用,最小抑制浓度为12.5 g·L-1,对白色葡萄球菌、蜡状芽孢杆菌、金黄色葡萄球菌、枯草芽孢杆菌、大肠埃希菌细菌具有中等强度的抑制作用。结论:本文对假益智果实进行挥发油提取鉴定,其主要成分为萜类、长链烃类化合物。抗菌实验结果表明假益智果实挥发油对四联球菌具有较好的抗菌活性。     

海拔高度对黔产宽叶缬草中挥发油及乙酸龙脑酯含量的影响

目的:分析不同海拔高度黔产宽叶缬草中挥发油及乙酸龙脑酯含量的变化情况,为该药材的栽培区域的选择提供参考。方法:采用水蒸气蒸馏法提取宽叶缬草挥发油,利用GC测定宽叶缬草挥发油中乙酸龙脑酯的含量,通过SPSS 17.0统计软件分析挥发油含量、乙酸龙脑酯含量与海拔高度的相关性。结果:不同海拔高度黔产宽叶缬草中挥发油及乙酸龙脑酯含量均具有显著差异。挥发油平均质量分数2.20%,变幅1.34%~3.60%,挥发油含量总体随海拔的增高而呈降低趋势,存在显著负相关;挥发油中乙酸龙脑酯平均质量分数50.29%,变幅29.64%~64.87%,乙酸龙脑酯含量基本上随海拔的增高而呈降低趋势,但无显著相关性。结论:黔产宽叶缬草中挥发油含量与海拔高度密切相关,建议该药材栽培宜选海拔较低区域。     

海南产益智仁盐炙前后挥发性成分的GC-MS分析

目的:分析海南产益智仁盐炙前后挥发性成分的变化。方法:以水蒸气蒸馏法提取海南产益智仁的挥发油,采用GC-MS联用技术对挥发油的化学成分进行分析鉴定,并用峰面积归一化方法计算各组分的相对含量。结果:海南益智仁盐炙前后挥发油含量发生了量的变化(生品1.36%,盐炙品1.12%)。从益智仁生品和盐制品的挥发油中分别鉴定出53,48种化合物。其中盐制前后共有的有42种,盐制后未检出的有11种,新检出的有6种。结论:GC-MS分析结果表明,海南产益智仁中所含主要成分为单萜和倍半萜类化合物,经盐炙后其挥发油的组成及相对含量均发生了变化,这些变化将为进一步优化炮制工艺以及阐明益智仁盐炙前后不同炮制作用的科学内涵提供依据。     

柱前衍生化HPLC测定石榴籽油中石榴酸的含量

目的:石榴酸(C18∶3)在结构上为顺9,反11,顺13-十八碳三烯酸,为长链烃类,在200~400 nm没有吸收,无法直接用紫外检测器进行检测,本实验采用柱前衍生化方法,使石榴酸带上一个强发色团,使其在200~400 nm有最大吸收,建立石榴籽油中指标性成分石榴酸的柱前衍生化HPLC分析方法。方法:以ω-溴代苯乙酮作为衍生化试剂,以三乙醇胺为相转移催化剂,对石榴籽油进行柱前衍生化,色谱条件采用Diamonsi C18色谱柱(4.6 mm×250 mm,5μm),检测波长272 nm,以甲醇-乙腈-水(68.5∶20∶11.5)为流动相,柱温30℃,流速1.0 m L·min-1。结果:石榴酸在0.026 6~0.133 0 g·L-1(r=0.999)线性关系良好,平均加样回收率为98.7%,RSD 1.8%。结论:该法稳定性、重复性好,定量准确,可作为石榴籽油中石榴酸的定量方法,用于评价和控制石榴籽油的质量。