- 作者列表："Schiffer L","Bossey A","Kempegowda P","Taylor AE","Akerman I","Scheel-Toellner D","Storbeck KH","Arlt W
Objective:Androgens are important modulators of immune cell function. The local generation of active androgens from circulating precursors is an important mediator of androgen action in peripheral target cells or tissues. We aimed to characterize the activation of classic and 11-oxygenated androgens in human peripheral blood mononuclear cells (PBMCs). Methods:PBMCs were isolated from healthy male donors and incubated ex vivo with precursors and active androgens of the classic and 11-oxygenated androgen pathways. Steroids were quantified by liquid chromatography-tandem mass spectrometry. The expression of genes encoding steroid-metabolizing enzymes was assessed by quantitative PCR. Results:PBMCs generated eight-fold higher amounts of the active 11-oxygenated androgen 11-ketotestosterone than the classic androgen testosterone from their respective precursors. We identified the enzyme AKR1C3 as the major reductive 17β-hydroxysteroid dehydrogenase in PBMCs responsible for both conversions and found that within the PBMC compartment natural killer cells are the major site of AKRC13 expression and activity. Steroid 5α-reductase type 1 catalyzed the 5α-reduction of classic but not 11-oxygenated androgens in PBMCs. Lag time prior to the separation of cellular components from whole blood increased serum 11-ketotestosterone concentrations in a time-dependent fashion, with significant increases detected from two hours after blood collection. Conclusions:11-Oxygenated androgens are the preferred substrates for androgen activation by AKR1C3 in PBMCs, primarily conveyed by natural killer cell AKR1C3 activity, yielding 11-ketotestosterone the major active androgen in PBMCs. Androgen metabolism by PBMCs can affect the results of serum 11-ketotestosterone measurements, if samples are not separated in a timely fashion. Significance statement:We show that human peripheral blood mononuclear cells (PBMCs) preferentially activate 11-ketotestosterone rather than testosterone when incubated with precursors of both the classic and the adrenal-derived 11-oxygenated androgen biosynthesis pathways. We demonstrate that this activity is catalyzed by the enzyme AKR1C3, which we found to primarily reside in natural killer cells, major contributors to the anti-viral immune defense. This potentially links intracrine 11-oxygenated androgen generation to the previously observed decreased NK cell cytotoxicity and increased infection risk in primary adrenal insufficiency. In addition, we show that PBMCs continue to generate 11-ketotestosterone if the cellular component of whole blood samples is not removed in a timely fashion, which could affect measurements of this active androgen in routine clinical biochemistry.
目的: 雄激素是免疫细胞功能的重要调节剂。从循环前体局部产生活性雄激素是外周靶细胞或组织中雄激素作用的重要介质。我们旨在表征人类外周血单核细胞 (pbmc) 中经典和11-氧合雄激素的激活。 方法: 从健康男性供体中分离pbmc，并与经典和11-氧合雄激素途径的前体和活性雄激素离体孵育。通过液相色谱-串联质谱法定量类固醇。通过定量PCR评估编码类固醇代谢酶的基因的表达。 结果: pbmc从其各自的前体中产生的活性11-氧化雄激素11-酮睾酮的量是经典雄激素睾酮的8倍。我们鉴定了AKR1C3酶是PBMC中负责两种转化的主要还原性17β-羟基类固醇脱氢酶，并发现PBMC隔室自然杀伤细胞是AKRC13表达和活性的主要位点。类固醇5α-还原酶1型催化pbmc中经典但非11-氧合雄激素的5α-还原。从全血中分离细胞组分之前的滞后时间以时间依赖性方式增加了血清11-酮睾酮浓度，从采血后两小时检测到显著增加。 结论: 11-氧合雄激素是pbmc中AKR1C3激活雄激素的优选底物，主要由自然杀伤细胞AKR1C3活性传递，产生11-酮睾酮，这是pbmc中主要的活性雄激素。如果样品没有及时分离，pbmc的雄激素代谢会影响血清11-酮睾酮测量的结果。 显著性声明: 我们表明，当与经典和肾上腺来源的11-氧合雄激素生物合成途径的前体一起孵育时，人外周血单核细胞 (pbmc) 优先激活11-酮睾酮而不是睾酮。我们证明这种活性是由AKR1C3酶催化的，我们发现它主要存在于自然杀伤细胞中，这是抗病毒免疫防御的主要贡献者。这可能将胞内11-氧合雄激素生成与先前观察到的原发性肾上腺功能不全中NK细胞细胞毒性降低和感染风险增加联系起来。此外，我们表明，如果全血样品的细胞成分没有及时去除，pbmc会继续产生11-酮睾酮，这可能会影响常规临床生物化学中这种活性雄激素的测量。
METHODS::The ATP binding-cassette superfamily corresponds the mostly transmembrane transporters family found in humans. These proteins actively transport endogenous and exogenous substrates through biological membranes in body tissues, so they have an important role in the regulation of many physiological functions necessary for human homeostasis, as well as in response regulation to several pharmacological substrates. The development of multidrug resistance has become one of the main troubles in conventional chemotherapy in different illnesses including cancer, being the increased efflux of antineoplastic drugs the main reason for this multidrug resistance, with a key role of the ABC superfamily. Likely, the interindividual variability in the pharmacological response among patients is well known, and may be due to intrinsically factors of the disease, genetic and environmental ones. Thus, the understanding of this variability, especially the genetic variability associated with the efficacy and toxicity of drugs, can provide a safer and more effective pharmacological treatment, so ABC genes are considered as important regulators due to their relationship with the reduction in pharmacological response. In this review, updated information about transporters belonging to this superfamily was collected, the possible role of these transporters in cancer, the role of genetic variability in their genes, as well as some therapeutic tools that have been tried to raise against main transporters associated with chemoresistance in cancer.
METHODS:BACKGROUND:Cholinergic neurotransmission regulates neuroinflammation in Parkinson disease (PD). RESEARCH DESIGN AND METHODS:The authors conducted a delayed-start study of donepezil for cognitive decline in non-demented PD patients. The study consisted of a 96-week randomized placebo-controlled double-blind phase 1, followed by a 24-week donepezil extension phase 2. The primary outcome measure was a change in the Mini-Mental State Examination (MMSE) at week 120. RESULTS:A total of 98 patients were randomly allocated to the early-start (donepezil-to-donepezil) and delayed-start (placebo-to-donepezil) groups. Mean (SD) of the baseline MMSE was 27.6 (2.0) and 28.0 (2.1), respectively. MMSE change at week 120 was better in the early-start group than in the delayed-start group, but the difference was not significant. The MMSE declined in apolipoprotein ε4 carriers, but not in non-carriers, and the factor interaction (intervention × ε4 genotype) was highly significant (P < 0.001). Analyzed with the interaction, the difference was significant (group difference 1.95 [0.33 to 3.57], P = 0.018). The MMSE decline slope in phase 1 was significantly better in the early-start group than in the delayed-start group (P = 0.048). CONCLUSIONS:Cognitive function deteriorated in ε4 carriers, but not in non-carriers, and early-start donepezil may postpone cognitive decline in the former.
METHODS::Since the discovery of dental pulp stem cells, a lot of teams have expressed an interest in dental pulp regeneration. Many approaches, experimental models and biological explorations have been developed, each including the use of stem cells and scaffolds with the final goal being clinical application in humans. In this review, the authors' objective was to compare the experimental models and strategies used for the development of biomaterials for tissue engineering of dental pulp with stem cells. Electronic queries were conducted on PubMed using the following terms: pulp regeneration, scaffold, stem cells, tissue engineering and biomaterial. The extracted data included the following information: the strategy envisaged, the type of stem cells, the experimental models, the exploration or analysis methods, the cytotoxicity or viability or proliferation cellular tests, the tests of scaffold antibacterial properties and take into account the vascularization of the regenerated dental pulp. From the 71 selected articles, 59% focused on the "cell-transplantation" strategy, 82% used in vitro experimentation, 58% in vivo animal models and only one described an in vivo in situ human clinical study. 87% used dental pulp stem cells. A majority of the studies reported histology (75%) and immunohistochemistry explorations (66%). 73% mentioned the use of cytotoxicity, proliferation or viability tests. 48% took vascularization into account but only 6% studied the antibacterial properties of the scaffolds. This article gives an overview of the methods used to regenerate dental pulp from stem cells and should help researchers create the best development strategies for research in this field.