京尼平苷的药代动力学研究进展

环烯醚萜类化合物京尼平苷具有降血糖、抗炎、神经保护、对大鼠心肌缺血再灌注损伤的保护等多种药理作用,具有广泛的药用价值。目前,对京尼平苷的药代动力学研究已取得一些成果,本文系统阐述了京尼平苷单体、栀子复方药物中及疾病状态下京尼平苷药代动力学方面的研究,为京尼平苷的进一步研究和开发应用提供参考。     

栀子的化学成份及其药理活性

栀子是茜草科栀子属植物,是药食两用植物,其果实具有清热解毒等多种功效。其主要化学成份有环烯醚萜类、有机酸(酯)、黄酮、香豆素、挥发油等。文章主要对栀子的环烯醚萜类及单萜苷类化学成份及其药理活性作一综述。     

β-甘露聚糖酶催化水解栀子苷制备京尼平

京尼平是一种环烯醚萜类天然生物交联剂,具有降血糖、调血脂、保肝利胆等生物活性。天然存在的京尼平较少,且质量分数约为0.005%~0.01%。采用β-甘露聚糖酶催化水解栀子苷制备京尼平的工艺路线,通过单因素实验、正交实验确定了β-甘露聚糖酶水解栀子苷的最佳工艺条件:p H为4.5,温度为50℃,底物与酶质量比例1∶2,时间为1 h,产率高达84.49%,纯度达到80%以上。该方法安全、快速、可靠,是一种生产京尼平的新途径。     

木樨榄属植物中裂环烯醚萜类的提取方法及开发前景

裂环烯醚萜类化合物是木樨榄属植物标记性化合物,尤其是橄榄苦苷具有重要的药理活性。本文作者研究了作者裂环烯醚萜类化合物植物来源、化学结构特征和物化性质及药理作用,提出木樨榄属油橄榄叶提取物加工工艺和橄榄苦苷的检测方法,为我国油橄榄叶中橄榄苦苷的加工利用提供依据。     

纤维素酶法提取玄参总环烯醚萜类成分的工艺优化

为了得到酶解法提取玄参中环烯醚萜类成分最佳提取工艺,通过高效液相色谱法测定环烯醚萜类成分中的哈巴俄苷、哈巴苷和桃叶珊瑚苷的提取率为考察目标,筛选最佳酶种类及用量,并在单因素试验基础上,考察料液比、溶剂pH、酶解温度、提取时间对提取率的影响,再进行正交试验优化,确定最佳提取工艺。实验结果表明,选取0.5%纤维素酶时提取率最高;纤维素酶提取玄参中环烯醚萜类成分最佳提取工艺为:料液比1∶15,溶剂pH=3.5,提取时间2 h,提取温度55℃。在此工艺条件下,环烯醚萜类成分的提取率可达2.254%,比传统热回流提取法可提高30%左右的提取率,比不加酶的条件可提高65%的提取率。     

鸡矢藤中环烯醚萜苷类提取工艺研究现状

鸡矢藤是传统中药,现代研究表明其中的环烯醚萜苷类具有较强的镇痛作用,其独特的化学结构和药理作用已引起人们的关注。文章从鸡矢藤中有效成分提取方法和环烯醚萜苷类的纯化富集方法两方面对鸡矢藤中环烯醚萜苷类的研究现状进行总结,为鸡矢藤中环烯醚萜苷类的开发利用提供参考依据,也为其进一步研究提供基础。     

环烯醚萜类化合物在防治糖尿病方面研究进展

目前糖尿病的治疗以口服西药为主,疗效迅速,但临床中多有不良反应的报道,不适于长期使用,易产生耐药性.近年来,不少学者以药材中提取出的天然化合物为主要成分,以期开发出治疗、预防糖尿病的新型药物.因此,在这一领域出现了大量的研究报道.其中,环烯醚萜苷类化合物梓醇、山茱萸环烯醚萜总苷、桃叶珊瑚苷等具有显著的降糖效果,并对糖尿...     

京尼平及其衍生物抗阿尔兹海默病作用的研究进展

京尼平(Genipin)是具有环烯醚萜结构的化合物,具有抗血栓、降血糖、抗肿瘤、抗炎和抗老年痴呆等多种药理活性.近年来,人们通过对其结构进行修饰改造,获得了一系列具有抗阿尔兹海默病(AD)活性的京尼平衍生物.对京尼平及其衍生物抗阿尔兹海默病作用的研究进展进行综述,为京尼平的开发利用提供依据.     

7,12-二甲基苯并蒽对人肝星状细胞活化的影响

探讨7,12-二甲基苯并蒽(DMBA)对肝星状细胞活化的影响。DMBA(1μmol·L-1)处理人肝星状细胞株LX-2 24h后,Western blot、ELISA和实时定量PCR观察肝星状细胞活化标志蛋白α-SMA、TGF-β1、CYP1A1和CYP1B1蛋白表达和分泌量以及mRNA表达。研究发现,与对照组相比,DMBA处理后的LX-2中α-SMA蛋白和mRNA表达均显著升高(P0.05),TGF-β1分泌量(P0.05)和mRNA表达(P0.01)也显著升高。此外,DMBA处理的LX-2中CYP1A1和CYP1B1的mRNA表达也显著升高(P0.05)。结果表明DMBA可活化人肝星状细胞,可能与诱导LX-2中CYP1A1和CYP1B1表达有关。     

超微粉碎-微波双水相萃取红花龙胆中环烯醚萜苷类

以红花龙胆全草为原料,采用超微粉碎和微波控温辅助双水相法提取了其中的环烯醚萜苷类。通过单因素实验和正交实验确定了最佳提取工艺;考察了所得环烯醚萜苷类的总抗氧化作用及其清除1,1-二苯基-2-三硝基苯肼自由基(DPPH·)的能力。结果表明,最佳提取工艺为:在30.0 g〔无水乙醇7.8 g(质量分数26%),磷酸氢二钾(K2HPO4)3.0 g (质量分数10%)〕乙醇/K2HPO4双水相体系中,红花龙胆干粉粒度为400目,微波温度(70±1)℃,微波时间110 s,红花龙胆干粉加入量3.5 g,得率为5.48%,相比传统提取工艺热回流得率(3.61%)显著提高。此法能抑制试材内源性水解酶活性且中和植酸(红花龙胆中的酸性物质)来降低溶出环烯醚萜苷类发生聚合反应的几率,有效解决了红花龙胆中环烯醚萜苷类需富集才能检测到的问题;总环烯醚萜苷类的抗氧化能力在0.2～0.6 g/L内强于2,6-二叔丁基-4-甲基苯酚(BHT),对DPPH·的清除能力在0.2～1.0 g/L内强于BHT。     

Leydig Cells in Immunocastrated Polish Landrace Pig Testis: Differentiation Status and Steroid Enzyme Expression Status

Porker immunocastration against gonadoliberin (GnRH) secretion has been utilized since 2009; however, consumers are still skeptical of it. This is due to not having full information available on the problem of a boar taint, as well as a lack of research on morphological and molecular changes that may occur in the animal reproductive system and other body systems. The present study aimed to explore the functional status of steroidogenic Leydig cells of the testicular interstitial tissue in immunocastrated Polish Landrace pigs. Analyses were performed using Western blot, immunohistochemistry for relaxin (RLN), insulin-like 3 protein (INSL3), pelleted growth factor receptor α (PDGFRα), cytochrome P450scc, 3β- and 17β-hydroxysteroid dehydrogenases (3β-HSD, 17β-HSD), cytochrome P450arom, and 5α-reductase (5α-RED). Immunoassay ELISA was used to measure the androstenone, testosterone, and estradiol levels in the testis and serum of immunocastrates. We revealed disturbances in the distribution and expression of (i) RLN, indicating an inflammatory reaction in the interstitial tissue; (ii) INSL3 and PDGFRα, indicating alterations in the differentiation and function of fetal, perinatal, or adult Leydig cell populations; (iii) P450scc, 3β-HSD, 17β-HSD, P450arom, and 5α-RED, indicating disturbances in the sex steroid hormone production and disturbed functional status of Leydig cells; as well as (iv) decreased levels of androstenone, testosterone, and estradiol in testicular tissue and serum, indicating the dedicated action of Improvac to reduce boar taint at both the hypothalamic–hypophysis–gonadal axis and local level (Leydig cells). In summary, our study provides a significant portion of knowledge on the function of Leydig cells after immunocastration, which is also important for the diagnosis and therapy of testis dysfunction due to GnRH action failure and/or Leydig cell differentiational–functional alterations.     

Adult Exposure to Di-N-Butyl Phthalate (DBP) Induces Persistent Effects on Testicular Cell Markers and Testosterone Biosynthesis in Mice

Studies indicate that phthalates are endocrine disruptors affecting reproductive health. One of the most commonly used phthalates, di-n-butyl phthalate (DBP), has been linked with adverse reproductive health outcomes in men, but the mechanisms behind these effects are still poorly understood. Here, adult male mice were orally exposed to DBP (10 or 100 mg/kg/day) for five weeks, and the testis and adrenal glands were collected one week after the last dose, to examine more persistent effects. Quantification of testosterone, androstenedione, progesterone and corticosterone concentrations by liquid chromatography-mass spectrometry showed that testicular testosterone was significantly decreased in both DBP treatment groups, whereas the other steroids were not significantly altered. Western blot analysis of testis revealed that DBP exposure increased the levels of the steroidogenic enzymes CYP11A1, HSD3β2, and CYP17A1, the oxidative stress marker nitrotyrosine, and the luteinizing hormone receptor (LHR). The analysis further demonstrated increased levels of the germ cell marker DAZL, the Sertoli cell markers vimentin and SOX9, and the Leydig cell marker SULT1E1. Overall, the present work provides more mechanistic understanding of how adult DBP exposure can induce effects on the male reproductive system by affecting several key cells and proteins important for testosterone biosynthesis and spermatogenesis, and for the first time shows that these effects persist at least one week after the last dose. It also demonstrates impairment of testosterone biosynthesis at a lower dose than previously reported.     

重组大肠杆菌表达17β-羟基类固醇脱氢酶全细胞催化合成宝丹酮的研究

宝丹酮作为一种重要的蛋白同化雄性激素类固醇,具有提升肌肉质量和耐力的功能。宝丹酮的传统合成方法是以1,4-雄烯二酮（ADD）为底物通过化学法合成,但过程复杂、污染严重。17β-羟基类固醇脱氢酶（17β-HSD）可催化甾体化合物C-17位点的氧化还原反应,实现ADD和宝丹酮的相互转化。本研究通过基因序列同源性分析,筛选到6种不同来源的17β-HSD基因并对其在大肠杆菌中进行异源表达。利用不同重组菌转化ADD合成宝丹酮,结果表明重组菌BL21/pET28a-HSDPy的ADD转化率最高,因此选择BL21/pET28a-HSDPy进行进一步研究。鉴定了重组菌的酶学性质并优化其全细胞转化条件。结果表明在生物量为36 g·L^-1、底物浓度为5.40 g·L^-1条件下,经过两次补料,获得了3.66 g·L^-1宝丹酮,比优化前提高了4.1倍。而且在生物转化过程中未检测到副产物。为生物合成宝丹酮提供了可能。     

Hippocampal Expression of Cytochrome P450 1B1 in Penetrating Traumatic Brain Injury

Hippocampal dysfunction contributes to multiple traumatic brain injury sequala. Female rodents’ outcome is superior to male which has been ascribed the neuroprotective sex hormones 17β-estradiol and progesterone. Cytochrome P450 1B1 (CYP1B1) is an oxidative enzyme influencing the neuroinflammatory response by creating inflammatory mediators and metabolizing neuroprotective 17β-estradiol and progesterone. In this study, we aimed to describe hippocampal CYP1B1 mRNA expression, protein presence of CYP1B1 and its key redox partner Cytochrome P450 reductase (CPR) in both sexes, as well as the effect of penetrating traumatic brain injury (pTBI). A total 64 adult Sprague Dawley rats divided by sex received pTBI or sham-surgery and were assigned survival times of 1-, 3-, 5- or 7 days. CYP1B1 mRNA was quantified using in-situ hybridization and immunohistochemistry performed to verify protein colocalization. CYP1B1 mRNA expression was present in all subregions but greatest in CA2 irrespective of sex, survival time or intervention. At 3-, 5- and 7 days post-injury, expression in CA2 was reduced in male rats subjected to pTBI compared to sham-surgery. Females subjected to pTBI instead exhibited increased expression in all CA subregions 3 days post-injury, the only time point expression in CA2 was greater in females than in males. Immunohistochemical analysis confirmed neuronal CYP1B1 protein in all hippocampal subregions, while CPR was limited to CA1 and CA2. CYP1B1 mRNA is constitutively expressed in both sexes. In response to pTBI, females displayed a more urgent but brief regulatory response than males. This indicates there may be sex-dependent differences in CYP1B1 activity, possibly influencing inflammation and neuroprotection in pTBI.     

Time-Course Changes of Steroidogenic Gene Expression and Steroidogenesis of Rat Leydig Cells after Acute Immobilization Stress

Leydig cells secrete testosterone, which is essential for male fertility and reproductive health. Stress increases the secretion of glucocorticoid (corticosterone, CORT; in rats), which decreases circulating testosterone levels in part through a direct action by binding to the glucocorticoid receptors (NR3C1) in Leydig cells. The intratesticular CORT level is dependent on oxidative inactivation of glucocorticoid by 11β-hydroxysteroid dehydrogenase 1 (HSD11B1) in Leydig cells. In the present study, we investigated the time-course changes of steroidogenic gene expression levels after acute immobilization stress in rats. The plasma CORT levels were significantly increased 0.5, 1, 3 and 6 h after immobilization stress, while plasma testosterone levels were significantly reduced 3 and 6 h, after stress and luteinizing hormone (LH) did not change. Immobilization stress caused the down-regulation of Scarb1, Star and Cyp17a1 expression levels in the rat testis starting at the first hour of stress, ahead of the significant decreases of plasma testosterone levels. Other mRNA levels, including Cyp11a1, Hsd3b1 and Hsd17b3, began to decline after 3 h. Hsd11b1 and Nos2 mRNA levels did not change during the course of stress. Administration of glucocorticoid antagonist RU486 significantly restored plasma testosterone levels. In conclusion, Scarb1, Star and Cyp17a1 expression levels are more sensitive to acute stress, and acute immobilization stress causes the decline of the steroidogenic pathway via elevating the levels of glucocorticoid, which binds to NR3C1 in Leydig cells to inhibit steroidogenic gene expression.     

Baicalin Protects Mice from Aristolochic Acid I-Induced Kidney Injury by Induction of CYP1A through the Aromatic Hydrocarbon Receptor

Exposure to aristolochic acid I (AAI) can lead to aristolochic acid nephropathy (AAN), Balkan endemic nephropathy (BEN) and urothelial cancer. The induction of hepatic CYP1A, especially CYP1A2, was considered to detoxify AAI so as to reduce its nephrotoxicity. We previously found that baicalin had the strong ability to induce CYP1A2 expression; therefore in this study, we examined the effects of baicalin on AAI toxicity, metabolism and disposition, as well as investigated the underlying mechanisms. Our toxicological studies showed that baicalin reduced the levels of blood urea nitrogen (BUN) and creatinine (CRE) in AAI-treated mice and attenuated renal injury induced by AAI. Pharmacokinetic analysis demonstrated that baicalin markedly decreased AUC of AAI in plasma and the content of AAI in liver and kidney. CYP1A induction assays showed that baicalin exposure significantly increased the hepatic expression of CYP1A1/2, which was completely abolished by inhibitors of the Aromatic hydrocarbon receptor (AhR), 3ʹ,4ʹ-dimethoxyflavone and resveratrol, in vitro and in vivo, respectively. Moreover, the luciferase assays revealed that baicalin significantly increased the luciferase activity of the reporter gene incorporated with the Xenobiotic response elements recognized by AhR. In summary, baicalin significantly reduced the disposition of AAI and ameliorated AAI-induced kidney toxicity through AhR-dependent CYP1A1/2 induction in the liver.     

Influence of Commercial Dietary Oils on Lipid Composition and Testosterone Production in Interstitial Cells Isolated from Rat Testis

The aim of this study was to examine the influence of dietary fat on lipid composition, as well as on the steroidogenic function of interstitial cells isolated from Wistar rats that had been fed semi-synthetic diets containing four different commercial oils (S soybean, O olive, C coconut, and G grape seed). Steroidogenic enzyme activities, lipid composition, and androgen production were measured in testicular interstitial cells. Lipid analysis included measurement of the contents of major lipid subclasses (neutral lipids, polar lipids, free and esterified cholesterol), as well as principal polar and neutral lipid fatty acyl compositions. Significant differences in lipid composition were observed among the groups, most of them reflecting the specific fatty acyl composition of the diet tested. Testosterone concentration was higher in O and C groups compared with S or G. In agreement with this observation, the activity of both key enzymes involved in testosterone biosynthesis (3-β-HSD and 17-β-HSD) was higher in O and C groups with significant differences between them (O > C). A significant negative correlation was found between cellular testosterone production and cellular cholesterol ester content. Additionally, testosterone concentration directly correlated with cholesterol levels. We conclude that dietary oils qualitatively and quantitatively modified the lipid composition of interstitial cells, producing either a direct or indirect regulatory effect on testicular steroidogenic function.     

Epigenetic Determinants of CYP1A1 Induction by the Aryl Hydrocarbon Receptor Agonist 3,3',4,4',5-Pentachlorobiphenyl (PCB 126)

Many enzymes involved in xenobiotic metabolism, including cytochrome P450 (CYP) 1A1, are regulated by the aryl hydrocarbon receptor (AhR). 3,3'',4,4'',5-Pentachlorobiphenyl (PCB 126) is a potent ligand for AhR and can thus induce the expression of CYP1A1. Interestingly, we observed that human carcinoma cell lines derived from different types of epithelial cells displayed divergent degrees of CYP1A1 induction after exposure to PCB 126. Since epigenetic mechanisms are known to be involved in cell type-specific gene expression, we sought to assess the epigenetic determinants of CYP1A1 induction in these carcinoma cell lines. In contrast to HepG2 hepatocarcinoma cells, HeLa cervical carcinoma cells showed significantly lower levels of CYP1A1 mRNA expression following PCB 126 exposure. Our results show that the two cell lines maintained differences in the chromatin architecture along the CYP1A1 promoter region. Furthermore, treatment with the epigenetic modifiers, trichostatin A (TSA) and 5-aza-2''-deoxycytidine (5-Aza-dC), significantly increased the expression of CYP1A1 after PCB 126 treatment in HeLa cells. However, we did not observe apparent differences in methylation levels or specific location of CpG DNA methylation between the two cell lines in the analyzed CYP1A1 promoter region. Taken together, our findings suggest that the differences in CYP1A1 expression between HepG2 and HeLa cells are due to differences in the chromatin architecture of the CYP1A1 promoter and thus establish a role of epigenetic regulation in cell-specific CYP1A1 expression.     

Hydroxylumisterols,Photoproducts of Pre-Vitamin D3, Protect Human Keratinocytes against UVB-Induced Damage

Lumisterol (L3) is a stereoisomer of 7-dehydrocholesterol and is produced through the photochemical transformation of 7-dehydrocholesteol induced by high doses of UVB. L3 is enzymatically hydroxylated by CYP11A1, producing 20(OH)L3, 22(OH)L3, 20,22(OH)2L3, and 24(OH)L3. Hydroxylumisterols function as reverse agonists of the retinoic acid-related orphan receptors α and γ (RORα/γ) and can interact with the non-genomic binding site of the vitamin D receptor (VDR). These intracellular receptors are mediators of photoprotection and anti-inflammatory activity. In this study, we show that L3-hydroxyderivatives significantly increase the expression of VDR at the mRNA and protein levels in keratinocytes, both non-irradiated and after UVB irradiation. L3-hydroxyderivatives also altered mRNA and protein levels for RORα/γ in non-irradiated cells, while the expression was significantly decreased in UVB-irradiated cells. In UVB-irradiated keratinocytes, L3-hydroxyderivatives inhibited nuclear translocation of NFκB p65 by enhancing levels of IκBα in the cytosol. This anti-inflammatory activity mediated by L3-hydroxyderivatives through suppression of NFκB signaling resulted in the inhibition of the expression of UVB-induced inflammatory cytokines, including IL-17, IFN-γ, and TNF-α. The L3-hydroxyderivatives promoted differentiation of UVB-irradiated keratinocytes as determined from upregulation of the expression at the mRNA of involucrin (IVL), filaggrine (FLG), and keratin 14 (KRT14), downregulation of transglutaminase 1 (TGM1), keratins including KRT1, and KRT10, and stimulation of ILV expression at the protein level. We conclude that CYP11A1-derived hydroxylumisterols are promising photoprotective agents capable of suppressing UVB-induced inflammatory responses and restoring epidermal function through targeting the VDR and RORs.