促卵泡激素通过活性氧途径调控卵巢癌细胞Nrf2蛋白的表达

目的 通过观察促卵泡激素(FSH)、活性氧(ROS)及其特异性抑制剂对卵巢癌细胞中红系衍生的核因子2相关因子2(nuclear factor-erythroid 2-related factor-2,Nrf2)表达的影响,探讨FSH是否通过ROS途径调控卵巢癌细胞Nrf2的表达.方法 (1)采用免疫组织化学方法检测Nrf2在卵巢癌良恶性组织中的表达.(2)用不同浓度的FSH刺激卵巢癌Hey细胞不同时间,采用蛋白质印迹法检测细胞内Nrf2蛋白的表达.(3)采用ROS检测试剂盒检测80 mIU/ml的FSH刺激后不同时间Hey细胞内ROS的生成情况.(4)Hey细胞经不同浓度的H2O2刺激48 h后,或经ROS特异性抑制剂N-乙酰半胱氨酸(NAC)预处理后加入150 mmol/L的H2O2处理48 h,观察细胞内Nrf2的表达.(5)Hey细胞经不同浓度的NAC预处理1h,加入80 mIU/ml的FSH共孵育48 h,观察细胞内Nrf2表达的变化.结果 (1)10例良性卵巢囊肿组织中仅3例有Nrf2蛋白的弱阳性表达,而64例卵巢癌组织中42例(65.6％)有Nrf2蛋白的阳性表达,两组差异有统计学意义(P=0.042).(2)FSH可上调Hey细胞内Nrf2的表达,并呈一定的剂量、时间依赖效应.(3) FSH可促进Hey细胞ROS的产生.(4) H2O2可诱导Hey细胞Nrf2蛋白的表达,且其作用可被NAC阻断.(5)NAC可阻断FSH所诱导的Nrf2蛋白的表达.结论 FSH可促进卵巢癌Hey细胞中ROS产生,上调Nrf2蛋白表达,抑制ROS途径可阻断FSH诱导的Nrf2高表达.提示FSH可能通过ROS途径调控卵巢癌Nrf2的表达,进而促进肿瘤发生.     

外源性胆绿素对中波紫外线诱导的角质形成细胞光损伤的保护作用和机制

【摘要】 目的 探讨外源性胆绿素对中波紫外线（UVB）照射的HaCaT细胞光损伤的保护作用。方法 将HaCaT细胞分为加入0、0.1、1、10 μmol/L胆绿素并照射UVB的UVB组、0.1 μmol/L UVB组、1 μmol/L UVB组、10 μmol/L UVB组及不做处理的对照组。UVB照射剂量为30 mJ/cm2,照射后继续培养24 h,分别检测细胞活性氧（ROS）水平、超氧化物歧化酶（SOD）活力、丙二醛（MDA）含量,ELISA法检测各组细胞的炎症因子白细胞介素6（IL-6）、IL-8水平。多组间均数比较采用单因素方差分析,组间两两比较采用LSD-t检验。结果 UVB组、0.1 μmol/L UVB 组、1 μmol/L UVB组、10 μmol/L UVB组、对照组细胞ROS水平（3 613.33 ± 206.61、2 958.67 ± 193.87、2 678.33 ± 178.24、2 274.67 ± 118.81、1 905.67 ± 250.25）、SOD活力（24.41 ± 1.78、28.96 ± 2.21、29.75 ± 1.75、30.19 ± 2.29、37.52 ± 2.31）、MDA含量（5.61 ± 0.32、5.46 ± 0.55、4.65 ± 0.22、2.55 ± 0.93、1.31 ± 0.05）、IL-6水平、IL-8水平差异均有统计学意义（F值分别为 34.02、57.36、214.09、29.73、11.40,均P < 0.05）,UVB组ROS水平、MDA含量及IL-6、IL-8水平均高于另4组（均P < 0.05）,SOD活力均低于另4组（均P < 0.05）。结论 外源性胆绿素减轻UVB引起的HaCaT细胞的氧化损伤、减轻炎症反应和抑制脂质过氧化作用,对细胞光损伤有一定的保护作用。     

NADPH oxidase inhibition rescues keratinocytes from elevated oxidative stress in a 2D atopic dermatitis and psoriasis model

Emerging evidence suggests oxidative stress plays a role in the pathophysiology of both atopic dermatitis (AD) and psoriasis (PSO). We established in vitro models of AD and PSO skin, and characterized these models in regard to their oxidative stress state. Both AD and PSO model keratinocytes exhibited elevated reactive oxygen species (ROS) levels and accumulated more DNA damage than control cells after oxidative stress induced by 250 µmol/L H₂O₂. Elevated ROS levels and DNA damage accumulation could be inhibited by the NADPH oxidase (NOX) inhibitor diphenyleneiodonium (DPI). Further, immunofluorescence analysis revealed the presence of both NOX1 and NOX4 in keratinocytes. By inhibiting NOX1, stress-related signalling cascades and elevated ROS levels could be abrogated, and survival of AD and PSO cells improved. Taken together, this study reveals that inhibition of NOX inhibition could abrogate elevated oxidative stress in a 2D model of AD and PSO.     

Immunomodulatory active compounds from Tinospora cordifolia

Ethnopharmacological relevance

Tinospora cordifolia mentioned as “Rasayana” is extensively used in various herbal preparations for the treatment of different ailments for its general tonic, antiperiodic, antispasmodic, antiinflammatory, antiarthritic, antiallergic and antidiabetic properties. It is extensively used in Ayurveda due to its potential in improving the immune system and the body resistance against infections.

Aim of the study

The aim of the study was to isolate and characterise the immunomodulatory active compounds of Tinospora cordifolia.

Materials and methods

The immunomodulatory activity of different extracts, fractions and isolated compounds in relation to phagocytosis and reactive oxygen species production in human neutrophil cells have been investigated using the PMN phagocytic function studies, NBT, NO and chemiluminescence assay.

Results

The results obtained indicate that ethyl acetate, water fractions and hot water extract exhibited significant immunomodulatory activity with an increase in percentage phagocyctosis. Chromatographic purification of these fraction led to the isolation of a mixture of two compounds 2, 3 isolated for the first time from natural source and five known compounds 1, 4–7 which were characterized as 11-hydroxymustakone (2), N-methyl-2-pyrrolidone (3), N-formylannonain (1), cordifolioside A (4), magnoflorine (5), tinocordiside (6), syringin (7) by nuclear magnetic resonance (NMR) and mass spectrometry (MS) and comparing the spectral data with reported one. Cordifolioside A and syringin have been reported to possess immunomodulatory activity. Other five compounds showed significant enhancement in phagocytic activity and increase in nitric oxide and reactive oxygen species generation at concentration 0.1–2.5 μg/ml.

Conclusions

Seven immunomodulatory active compounds belonging to different classes have been isolated and characterised indicating that the immunomodulatory activity of Tinospora cordifolia may be attributed to the synergistic effect of group of compounds.     

Herbal medicines for the prevention of alcoholic liver disease: A review

Ethnopharmacological relevance

Long-term excess alcohol exposure leads to alcoholic liver disease (ALD)—a global health problem without effective therapeutic approach. ALD is increasingly considered as a complex and multifaceted pathological process, involving oxidative stress, inflammation and excessive fatty acid synthesis. Over the past decade, herbal medicines have attracted much attention as potential therapeutic agents in the prevention and treatment of ALD, due to their multiple targets and less toxic side effects. Several herbs, such as Cnidium monnieri (L.) Cusson (Apiaceae), Curcuma longa L. (Zingiberaceae) and Pueraria lobata (Willd.) Ohwi (Leguminosae), etc., have been shown to be quite effective and are being widely used in China today for the treatment of ALD when used alone or in combination.

Aim of the review

To review current available knowledge on herbal medicines used to prevent or treat ALD and their underlying mechanisms.

Materials and methods

We used the pre-set searching syntax and inclusion criteria to retrieve available published literature from PUBMED and Web of Science databases, all herbal medicines and their active compounds tested on ALD induced by both acute and chronic alcohol ingestion were included.

Results

A total of 40 experimental studies involving 34 herbal medicines and (or) active compounds were retrieved and reviewed. We found that all reported extracts and individual compounds from herbal medicines/natural plants could be beneficial to ALD, which might be attributed to regulate multiple critical targets involved in the pathways of oxidation, inflammation and lipid metabolism.

Conclusions

Screening chemical candidate from herbal medicine might be a promising approach to drug discovery for the prevention or treatment of ALD. However, further studies remain to be done on the systematic assessment of herbal medicines against ALD and the underlying mechanisms, as well as their quality control studies.     

Hepatoprotective potential of Tecomella undulata stem bark is partially due to the presence of betulinic acid

Ethnopharmacological relevance

Tecomella undulata (TU;` Family Bignoniaceae) is used in Indian Ayurvedic system of medicine for treating various diseases including hepatic ailments. It is also incorporated in various marketed hepatoprotective polyherbal formulations.

Aim

The present study was aimed at evaluating possible hepatoprotective role of isolated compounds from TU stem bark (TSB) using in vitro and in vivo experimental models.

Methods

In vitro cytotoxicity and hepatoprotective potential of various extract, fractions and isolated compounds from TU stem bark were evaluated using HepG2 cells. Rats were pre-treated with TU methanolic extract (TSB-7) or betulinic acid (MS-2) or silymarin for 7 days followed by a single dose of CCl₄ (0.5 ml/kg, i.p.). Plasma markers of hepatic damage, hepatic antioxidants and indices of lipid peroxidation along with microscopic evaluation of liver were assessed in control and treatment groups.

Results

TSB-2 and MS-1 accounted for significant cell death whereas; TSB-1, TBS-7, TSB-9, TSB-10 and, MS-2 did not register significant cytotoxicity. Further, non-cytotoxic components exhibited ascending grade of hepatoprotection in vitro (TSB-10<TSB-1<TSB-7<TSB-9<MS-2). Pre-treatment of TSB-7 or MS-2 to CCl₄ treated rats prevented hepatocyte damage as evidenced by biochemical and histopathological observations.

Conclusion

It can be concluded that, hepatoprotective potential of Tecomella undulata stem bark is partially due to the presence of betulinic acid.     

活性氧与线粒体损伤

活性氧(reactive oxygen species,ROS)是细胞代谢不可避免的产物。细胞内高水平的ROS直接或间接地参与细胞信号传导,诱导细胞凋亡,是肿瘤及许多其它疾病的共同发病机制。线粒体是细胞能量生成的重要细胞器,也是广受关注的细胞调节氧化应激的中枢。但ROS与线粒体损伤之间的关系,至今尚未完全清楚。近年来的研究表明,线粒体是ROS产生的主要场所,又是ROS作用最敏感的部位。ROS通过氧化线粒体心磷脂、线粒体DNA和线粒体重要的蛋白质对线粒体造成氧化损伤,进而诱导细胞凋亡。     

Effect of priming in subpopulations of peripheral neutrophils from patients with chronic periodontitis

Background: Patients with periodontal disease are reported to generate more reactive oxygen species (ROS) than matched controls, suggesting increased inflammatory defense activity. The purpose of this study is to determine whether there are subpopulations of peripheral neutrophils in patients with chronic periodontitis (CP) that generate different levels of intracellular ROS when primed with tumor necrosis factor‐α (TNF‐α) or the chemokine interleukin‐8 (IL‐8, CXCL8) compared to controls. Methods: Venous blood was collected from 13 patients with CP despite careful maintenance over 2 to 8 years and from 13 healthy age‐ and sex‐matched controls. Neutrophils were separated from whole blood over a Percoll gradient and then activated via the Fcγ receptor with opsonized Staphylococcus aureus after priming with TNF‐α or IL‐8. The samples were analyzed by flow cytometry using the fluorescent probe dihydrorhodamine 123. Generation of ROS was measured as the intensity of fluorescence (IFL). Results: Two subpopulations were found in both patients and controls: one with low and one with high generation of IFL. The subpopulation with high generation of IFL in patients with CP was more responsive to IL‐8 (P <0.05) than the same subpopulation in healthy controls. No other differences in generation of ROS or priming effects were found between patients with CP and controls. Generation of ROS was dependent on nicotinamide adenine dinucleotide phosphate oxidase, and the intracellular ROS was primarily the oxygen anion. Conclusion: Patients with CP had a subpopulation of peripheral neutrophils that were more responsive to IL‐8 priming than controls.