Dietary n-3 long chain PUFA supplementation promotes a pro-resolving oxylipin profile in the brain

The brain is highly enriched in long chain polyunsaturated fatty acids (LC-PUFAs) that display immunomodulatory properties in the brain. At the periphery, the modulation of inflammation by LC-PUFAs occurs through lipid mediators called oxylipins which have anti-inflammatory and pro-resolving activities when derived from n-3 LC-PUFAs and pro-inflammatory activities when derived from n-6 LC-PUFAs. However, whether a diet rich in LC-PUFAs modulates oxylipins and neuroinflammation in the brain has been poorly investigated. In this study, the effect of a dietary n-3 LC-PUFA supplementation on oxylipin profile and neuroinflammation in the brain was analyzed. Mice were given diets deficient or supplemented in n-3 LC-PUFAs for a 2-month period starting at post-natal day 21, followed by a peripheral administration of lipopolysaccharide (LPS) at adulthood. We first showed that dietary n-3 LC-PUFA supplementation induced n-3 LC-PUFA enrichment in the hippocampus and subsequently an increase in n-3 PUFA-derived oxylipins and a decrease in n-6 PUFA-derived oxylipins. In response to LPS, n-3 LC-PUFA deficient mice presented a pro-inflammatory oxylipin profile whereas n-3 LC-PUFA supplemented mice displayed an anti-inflammatory oxylipin profile in the hippocampus. Accordingly, the expression of cyclooxygenase-2 and 5-lipoxygenase, the enzymes implicated in pro- and anti-inflammatory oxylipin synthesis, was induced by LPS in both diets. In addition, LPS-induced pro-inflammatory cytokine increase was reduced by dietary n-3 LC-PUFA supplementation. These results indicate that brain n-3 LC-PUFAs increase by dietary means and promote the synthesis of anti-inflammatory derived bioactive oxylipins. As neuroinflammation plays a key role in all brain injuries and many neurodegenerative disorders, the present data suggest that dietary habits may be an important regulator of brain cytokine production in these contexts.     

灯盏乙素介入IP3R-Ca2+途径抑制β淀粉样蛋白诱导的神经细胞凋亡

目的：观察灯盏乙素（Scu）对β淀粉样蛋白（Aβ）诱导的细胞模型中1，4，5-三磷酸肌醇受体（IP₃R）-Ca²⁺途径的影响，探讨其在阿尔茨海默病（AD）病程中可能发挥的积极作用。方法：选用神经母细胞瘤细胞分为对照组、Scu处理组、Aβ处理组、Aβ+Scu （高、中、低）处理组及Aβ+IP₃R拮抗剂组，用CCK-8法筛选药物浓度并检测各组细胞生存率；用酶联免疫吸附法检测各组细胞中1，4，5-三磷酸肌醇（IP₃）的含量；用蛋白印迹和实时荧光定量聚合酶链反应方法检测各组细胞IP₃R和凋亡相关因子Caspase-3、Bcl-2、Bax的蛋白及mRNA的表达水平；用激光共聚焦显微镜观察各组细胞内Ca²⁺浓度的变化；用AnnexinV/PI双染法测定各组细胞的凋亡率。结果：与对照组和Scu处理组相比，Aβ处理组细胞存活率下降，IP₃含量升高，IP₃R、Bax和Caspase-3的蛋白及mRNA表达上调，Bcl-2蛋白及mRNA的表达下调，细胞胞浆内Ca²⁺浓度及细胞凋亡率升高；Aβ+Scu处理组细胞中各检测指标的变化与Aβ处理组的结果正好相反，IP₃R通道下游指标的变化与Aβ+IP₃R拮抗剂组基本一致。结论：Scu能够下调通路蛋白IP₃、IP₃R的表达，抑制Aβ介导的Ca²⁺内流所致的细胞凋亡，可能通过对IP₃R-Ca²⁺途径的调控来影响AD病程。     

Investigation of non-linear Mate1-mediated efflux of trimethoprim in the mouse kidney as the mechanism underlying drug-drug interactions between trimethoprim and organic cations in the kidney

The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with K_i values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with K_m values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CL_R) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CL_R (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CL_R of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates.     

Synthesis,in vivo and in silico evaluation of novel 2,3-dihydroquinazolin-4(1H)-one derivatives as potential anticonvulsant agents

In light of the pharmacophoric structural requirements for achieving anticonvulsant activity, a series of N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)benzamide (4a-g) and N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)-2-phenylacetamide (4h-n) derivatives were synthesized in two steps starting from the reaction of N-methyl isatoic anhydride with the appropriate hydrazide and followed by condensation with the appropriate aldehyde. The anticonvulsant activities of the synthesized compounds were evaluated according to the anticonvulsant drug development (ADD) programme protocol. Among the synthesized compounds, 4n showed promising activity in both the maximal electroshock (MES) and pentylenetetrazole (PTZ) tests with median effective dose (ED₅₀) values of 40.7 and 6 mg/kg, respectively. The six most promising derivatives, 4b , 4a , 4c , 4f , 4j , and 4i , showed very low ED₅₀ values in the PTZ test (3.1, 4.96, 8.68, 9.89, 12, and 13.53 mg/kg, respectively). All the tested compounds showed no to low neurotoxicity in the rotarod test with a wide therapeutic index. Docking studies of compound 4n suggested that GABA_A binding could be the mechanism of action of these derivatives. The in silico drug likeliness parameters indicated that none of the designed compounds violate Lipinski's rule of five and that they are able to cross the blood–brain barrier.

Serum retinol-binding protein 4 is associated with insulin resistance in patients with early and untreated rheumatoid arthritis

ObjectiveRetinol-binding protein 4 (RBP4), systemic inflammation and insulin resistance (IR) are linked, yet the determinants of RBP4 and its impact on IR in rheumatoid arthritis (RA) are incompletely understood. The aim of this study was to explore the prevalence of IR in RA and investigate whether the serum levels of RBP4 were associated with IR in patients with RA.MethodsIn this study, 403 individuals with newly diagnosed and untreated RA were consecutively recruited. We calculated the Disease Activity Score assessed using 28-joint counts for swelling and tenderness (DAS28). Levels of serum RBP4, interleukin-6 (IL-6) and tumor necrosis factor (TNF) α were tested. IR was defined as Homeostasis model assessment for insulin resistance (HOMA-IR) index greater than or equal 2.40.ResultsIn those 403 patients, 68 (16.9%) were male and the median age was 43 years (IQR: 36–52). There was an evidently positive correlation between increased serum levels of RBP4 and increasing severity of RA (DAS28) (r = 0.403, P < 0.001). Furthermore, a modest positive correlation between levels of serum RBP4 and HOMA-IR score (r = 0.251; P < 0.0001) was found. Eighty-five patients (21.1%) in patients with RA were defined as IR (HOMA-IR ≥ 2.40), which was significantly higher than in normal cases (4.7%). In the patients with IR, serum levels of RBP4 were higher when compared with those in patients free-IR P < 0.001. The IR distribution across the quartiles of RBP4 ranged between 5.0% (first quartile) to 39.0% (fourth quartile), P for trend < 0.001. For each 1unit increase of RBP4, the unadjusted and adjusted risk of IR increased by 8% (OR: 1.08; 95% CI: 1.05–1.11, P < 0.001) and 5% (1.05; 1.02–1.09, P = 0.001), respectively. When RBP4 was added to the model containing established significant risk factors, AUROC (standard error) was increased from 0.768 (0.025) to 0.807(0.021). A significant difference in the AUC between the established risk factors alone and the addition of RBP4 was observed (difference, 0.039[0.004]; P = 0.02).ConclusionElevated serum levels of RBP4 were associated with increased risk of IR and might be useful in identifying RA at risk for IR and/or impaired glucose tolerance for early prevention strategies, especially in obese and women patients     

负载IL-4及BMP-2的氧化石墨烯-羧甲基壳聚糖凝胶对骨免疫和骨修复的早期影响研究

目的探讨负载 IL-4 和 BMP-2 的氧化石墨烯（graphene oxide，GO）-羧甲基壳聚糖（carboxymethyl chitosan，CMC）凝胶诱导巨噬细胞 M2 型分化及对 BMSCs 成骨分化的影响。方法取 CMC、GO 制备混合溶液后，分别添加 PBS、IL-4、BMP-2 或 IL-4+BMP-2，在交联剂作用下制备单纯或负载不同因子的 GO-CMC 凝胶支架；取单纯 GO-CMC 凝胶表征观测，包括大体、扫描电镜及傅里叶变换红外吸收光谱仪（Fourier transform infrared spectroscopy，FTIR）检测，以单纯 CMC 凝胶作为对照；取负载不同因子的 GO-CMC 凝胶行体外缓释实验。取 4～5 周龄 SPF 级 SD 雌性大鼠分离培养巨噬细胞，分别与单纯以及负载不同因子的 GO-CMC 凝胶培养，24 h 后行 CD206 免疫荧光检测巨噬细胞分化情况；取第 3 代大鼠 BMSCs 分别与单纯以及负载不同因子的 GO-CMC 凝胶成骨诱导培养，10 d 后行 ALP 染色观测早期成骨，21 d 行茜素红染色观测晚期成骨。结果大体观察 GO-CMC 凝胶呈棕色、半透明状；扫描电镜观察示，GO-CMC 凝胶孔径及孔壁厚度与单纯 CMC 凝胶相似，但内壁粗糙度增加；FTIR 检测显示 CMC 发生聚合形成凝胶。体外缓释实验示 3 种负载不同因子的 GO-CMC 凝胶缓释性能相似，均呈线性缓慢释放因子。CD206 免疫荧光检测示 GO-CMC 凝胶可诱导巨噬细胞 M2 型分化，ALP 及茜素红染色示 GO-CMC 凝胶可诱导 BMSCs 成骨分化；其中负载 IL-4+BMP-2 的 GO-CMC 凝胶作用最显著（P<0.05）。 结论负载 IL-4 和 BMP-2 的 GO-CMC 凝胶可诱导巨噬细胞 M2 型分化，增强 BMSCs 成骨分化能力，为后期骨缺损修复及骨免疫调节研究提供了新的策略。     

Isolation and characterization of new human carrier peptides from two important vaccine immunogens

In the preparation of glycoconjugate vaccines in clinical practice, two highly immunogenic carrier proteins, CRM₁₉₇ and tetanus toxoid (TT), are predominantly conjugated with the capsular polysaccharides (CPSs) of bacterial pathogens. In addition, TT has long been used as an effective vaccine to prevent tetanus. While these carrier proteins play an important role in immunogenicity and vaccine design alike, their defined human major histocompatibility complex class II (MHCII) T cell epitopes are inadequately characterized. In this current work, we use mass spectrometry to identify the peptides from these carrier proteins that are naturally processed and presented by human B cells via MHCII pathway. The MHCII-presented peptides are screened for their T cell stimulation using primary CD4+ T cells from four healthy adult donors. These combined methods reveal a subset of eleven CD4+ T cell epitopes that proliferate and stimulate human T cells with diverse MHCII allelic repertoire. Six of these peptides stand out as potential immunodominant epitopes by responding in three or more donors. Additionally, we provide evidence of these natural epitopes eliciting more significant T cell responses in donors than previously published TT peptides selected from T cell epitope screening. This study serves toward understanding carrier protein immune responses and thus enables the use of these peptides in developing novel knowledge-based vaccines to combat persisting problems in glycoconjugate vaccine design.     

Mildly decreased preoperative bilirubin levels are associated with infections after shoulder and knee arthroplasty

Increasing numbers of arthroplasties are also accompanied by postoperative infections. The main purpose was to evaluate preoperative serum bilirubin levels between patients with and without infections after shoulder and knee arthroplasties. For this retrospective case-control single-center study, a total of 108 patients were extracted from a prospectively collected database. Eighteen patients with infections after shoulder (n = 8) and knee (n = 10) arthroplasty were matched by age, gender, and implant type in a 1:5-scenario to 90 patients (40 shoulders and 50 knees) without postoperative infection. Demographic data, preoperative blood parameters, and postoperative infection-related outcomes were evaluated. Total bilirubin was the only preoperative parameter significantly different between the infection (8.21 ± 3.25 μmol/L or 0.48 ± 0.19 mg/dL) and noninfection (10.78 ± 4.62 μmol/L or 0.63 ± 0.27 mg/dL; P = .014) group, while C-reactive protein and other liver parameters were similar between the groups. Significantly more controls (92.1%) had preoperative bilirubin levels above 8.72 μmol/L or 0.51 mg/dL than cases (7.9%; P = .007). The 5-year infection survival-rate was 65.6% for patients with preoperative bilirubin levels < 8.72 μmol/L or < 0.51 mg/dL and 91.2% with ≥ 8.72 μmol/L or ≥ 0.51 mg/dL. Mildly decreased preoperative bilirubin levels with a cutoff at 8.72 μmol/L or 0.51 mg/dL were significantly associated to patients with infections after shoulder and knee arthroplasty. There were no differences in other blood parameters or comorbidities between patients with infections and their matched-controls.     

臀部筋膜脂肪瓣修复坐骨结节和大转子复发性窦道型压疮

目的总结臀部筋膜脂肪瓣修复坐骨结节、大转子复发性窦道型压疮的效果。方法2018 年 2 月—2019 年 6 月，收治 12 例 13 处长期截瘫伴坐骨结节、大转子复发性窦道型压疮患者。其中男 10 例 11 处，女 2 例 2 处；年龄 46～56 岁，平均 51 岁。截瘫 10～20 年，平均 13 年；所有患者均有压疮手术史，术后 3 个月～12 年复发。其中坐骨结节处压疮 11 例，坐骨结节合并大转子处压疮 1 例。创面清创、切除窦道假性滑液囊，采用单侧或双侧臀部筋膜脂肪瓣填塞窦道，术区一期缝合闭合切口。结果术后 13 处压疮切口均Ⅰ期愈合，局部无红肿、渗液，术后 14 d 拆线出院。术后局部平坦，外观理想。术后患者均获随访，随访时间 8～24 个月，平均 14 个月。随访期间压疮均无复发。结论臀部脂肪组织丰富，利用筋膜脂肪瓣修复坐骨结节、大转子复发性窦道型压疮设计、操作简便，临床效果良好。