Response to sirolimus in capillary lymphatic venous malformations and associated syndromes: Impact on symptomatology,quality of life,and radiographic response

Background

Capillary lymphatic venous malformations (CLVM) and associated syndromes, including Klippel–Trenaunay syndrome (KTS) and congenital lipomatous overgrowth, vascular malformation, epidermal nevi, skeletal, and spinal syndrome (CLOVES), are underrecognized disorders associated with high morbidity from chronic pain, recurrent infections, bleeding, and clotting complications. The rarity of these disorders and heterogeneity of clinical presentations make large-scale randomized clinical drug trials challenging. Identification of PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha [gene]) mutations in CLVM has made targeted medications, such as sirolimus, attractive treatment options. The aim of this study was to investigate the safety and efficacy of sirolimus therapy in CLVM.

Procedure

A combined prospective and retrospective cohort of pediatric and young adult patients with CLVM treated with sirolimus was evaluated for disease response, including symptom improvement, quality of life (QOL), and radiologic response. Sirolimus dosing regimens and toxicities were also assessed.

Results

Twenty-nine patients with CLVM, including KTS and CLOVES, were included. Ninety-three percent of patients reported improved QOL, and 86% had improvement in at least one symptom. Most significantly, improvement was noted in 100% of patients with bleeding and 89% with thrombotic complications with corresponding decreases in mean D-dimer (p = .008) and increases in mean fibrinogen (p = .016). No patients had progressive disease on sirolimus. Most common side effects included neutropenia, lymphopenia, infection, and aphthous ulcers/stomatitis. No toxicities were life-threatening, and none required long-term discontinuation of sirolimus.

Conclusion

Sirolimus appears to be effective at reducing complications and improving QOL in patients with CLVM and associated syndromes. In this patient cohort, sirolimus was well tolerated and resulted in few treatment-related toxicities.     

miR-155靶向调节PIK3R1对类风湿关节炎大鼠模型PI3K/Akt/mTOR信号通路的影响

目的 探讨miR-155靶向调节PIK3R1对类风湿关节炎（rheumatoid arthritis,RA）大鼠PI3K/Akt/mTOR信号通路的影响。方法 SD大鼠随机分为对照组、模型组、miR-155 agomir组、miR-155 antagomir组、miR-155阴性对照组,诱导RA模型,分组处理后,观察关节症状,检测关节炎指数及后足趾容积;HE染色观察大鼠关节组织病理形态;使用试剂盒检测大鼠关节组织炎性因子IL-6、IL-17及IL-18水平;免疫印迹检测大鼠关节组织PI3K/Akt/mTOR信号通路蛋白表达;qRT-PCR实验检测大鼠关节组织miR-155及PIK3R1 mRNA水平;双荧光素酶报告基因实验检测miR-155对PIK3R1的靶向调控作用。结果 与对照组比较,模型组大鼠关节炎症状明显,关节炎指数、后足趾容积、关节组织炎性因子IL-6、IL-17及IL-18水平、关节组织p-PI3K/PI3K、p-Akt/Akt及p-mTOR/mTOR水平、关节组织miR-155水平明显升高（P＜0.05）,PIK3R1 mRNA水平明显降低（P＜0.05）。与模型组、miR-155阴性对照组比较,miR-155 antagomir组大鼠上述指标得到明显改善（P＜0.05）;miR-155 agomir组与miR-155 antagomir组趋势相反（P＜0.05）。结论 miR-155可靶向下调PIK3R1的表达,激活PI3K/Akt/mTOR信号,加重RA大鼠关节炎症损伤,下调miR-155表达,可抑制PI3K/Akt/mTOR信号激活及炎症反应发生发展,改善关节炎症状。     

迷迭香酸通过AMPK/mTOR通路减轻新生大鼠缺血缺氧性脑损伤研究

目的 探讨迷迭香酸对新生大鼠缺血缺氧脑损伤（hypoxic-ischemic encephalopathy,HIE）的影响,及其对单磷酸腺苷活化蛋白激酶（adenosine monophosphate activated protein kinase,AMPK）/雷帕霉素靶蛋白（mammalian target of rapamycin,mTOR）通路的调控作用,初步探讨其脑保护机制。方法 取7 d龄SD新生大鼠,随机分为对照组、模型组、迷迭香酸（300 mg/kg）组、AMPK/mTOR激动剂MT6378（10 mg/kg）组、AMPK抑制剂GSK-690693（30 mg/kg）组和迷迭香酸（300 mg/kg）+MT6378（10 mg/kg）组,每组20只。建立HIE模型,给予相应药物进行干预,采用TTC染色法检测大鼠脑梗死情况;透射电镜（TEM）观察大鼠海马神经元结构损伤及自噬状况;免疫荧光法检测大鼠海马神经元自噬标记物微管相关蛋白1轻链3B（microtubule-associated protein 1 light chain 3B,LC3B）阳性表达;TUNEL法检测大鼠海马神经元凋亡率;免疫组化法检测大鼠海马神经元磷酸化AMPK（p-AMPK）阳性表达;Western blotting检测大鼠海马组织活化的半胱氨酸蛋白酶3（cleaved Caspase-3）、mTOR及其磷酸化蛋白（p-mTOR）、Unc-51样自噬激活激酶1（uncoordinated-51 like autophagy activating kinase 1,Ulk1）及其磷酸化蛋白（p-Ulk1）、LC3B表达。结果 与对照组相比,模型组大鼠脑梗死严重,海马神经元结构损伤及自噬空泡形成较多,细胞自噬及凋亡水平升高,AMPK/mTOR通路活化（P<0.05）。与模型组相比,迷迭香酸组及GSK-690693组大鼠脑梗死、海马神经元结构损伤、凋亡及自噬减弱,AMPK/mTOR通路被抑制（P<0.05）;MT6378组海马组织AMPK/mTOR通路进一步激活,大鼠脑梗死、海马神经元结构损伤、凋亡及自噬进一步加重（P<0.05）;MT6378可逆转迷迭香酸的上述作用（P<0.05）。结论 迷迭香酸可能通过抑制AMPK/mTOR通路激活,降低海马神经元自噬及凋亡进程,发挥抗HIE脑损伤作用。     

mTOR通路对癫痫的影响及中医药干预作用研究进展

癫痫是常见的神经系统疾病,其发病机制复杂,病理改变亦多样化,以海马神经元细胞凋亡、胶质细胞增生、苔藓纤维出芽等为主要病理表现。近年来,国内外对于抗癫痫治疗专注于分子水平及其信号通路的研究,其中哺乳动物雷帕霉素靶蛋白(mTOR)这一信号通路通过细胞生长增殖、蛋白质代谢、细胞凋亡自噬、突触可塑性等对抗癫痫发挥重要的作用。中医药在治疗癫痫上疗效明显,大量实验证明中医药干预,包括中药单体、中药复方等治疗,能够通过mTOR信号通路发挥抗癫痫作用,从而减少癫痫发作频率、保护神经元细胞、改善癫痫症状等。mTOR信号通路也成为中医药治疗癫痫的重要靶点。现综述mTOR通路对癫痫的影响及中医药干预作用的研究进展。     

左、右归丸通过调节AMPK/mTOR通路抑制大鼠股骨成脂化的实验研究

目的基于AMPK/m TOR信号通路初步探讨左、右归丸对绝经后骨质疏松(postmenopausal osteoporsis,PMOP)大鼠成脂分化的调节机制。方法将60只雌性SD大鼠随机分为空白组(KB)、假手术组(SHAM)、模型组(OVX)、左归丸组(ZGW)、右归丸组(YGW)、补佳乐组(BJL)。除KB、SHAM组外,其余大鼠均摘除双侧卵巢,SHAM组大鼠摘除双侧卵巢周围等量脂肪,灌胃12周。应用数字化全身骨密度仪检测大鼠右侧股骨骨密度(bone mineral density,BMD),应用实时荧光定量PCR法检测大鼠右侧股骨PPARγ、AMPK、m TORC1 mRNA的表达,采用Western blot法检测大鼠右侧股骨PPARγ、C/EBPα、C/EBPβ蛋白的表达以及AMPKα、m TOR蛋白磷酸化水平。结果左、右归丸能明显升高PMOP大鼠右侧股骨BMD(P0.01),降低大鼠股骨成脂相关mRNA与蛋白的表达(P0.01或P0.05),降低AMPK mRNA的表达与蛋白磷酸化水平(P0.01),升高m TORC1 mRNA的表达与蛋白磷酸化水平(P0.01或P0.05);与ZGW组相比,YGW组PMOP大鼠右侧股骨BMD没有明显差异(P0.05),股骨成脂分化相关mRNA与蛋白的表达明显升高(P0.01),且AMPK mRNA的表达明显升高(P0.01),m TORC1 mRNA的表达与蛋白磷酸化水平降低(P0.01或P0.05)。结论左、右归丸通过AMPK/m TOR通路改善了PMOP大鼠股骨成脂分化过度,其作用机制可能与调节AMPK、m TOR mRNA的表达与蛋白磷酸化水平有关。     

Temsirolimus in Daily Use: Results of a Prospective Multicentre Noninterventional Study of Patients with Metastatic Kidney Cancer

Background

Temsirolimus (TEMSR) was approved for treating advanced renal cell carcinoma (RCC) in 2007. Based on the data from a single phase 3 trial, it is recommended explicitly as first-line therapy for patients with a poor clinical prognosis.

Objective

The aim of this prospective multicentre trial (STARTOR) was to examine the effectiveness of TEMSR in daily clinical practice with a broader indication in the treatment of metastatic RCC.

Design, setting, and participants

Metastatic RCC patients treated with 25 mg of TEMSR weekly were submitted to a prospective systematic evaluation and follow-up in 87 German centres between January 2008 and October 2011 using standardised procedures.

Outcome measurements and statistical analysis

All data were centrally analysed by an independent clinical research organisation.

Results and limitations

This interim analysis of the STARTOR study included 386 patients. The observed toxicity was tolerable, the median dose intensity was 91% (interquartile range: 79–100%), and the median treatment duration was 20.1 wk (95% confidence interval [CI], 17.0–23.3 wk). Clinical benefit was seen in 157 patients (40.7%); the median progression-free and overall survival were 4.9 mo (95% CI, 4.2–5.6) and 11.6 mo (95% CI, 9.3–13.9), respectively. The effectiveness of TEMSR did not differ significantly in relation to the patient's age, histologic RCC subtype, or line of treatment. The major limitations were the noninterventional study design, limited information about Memorial Sloan-Kettering Cancer Center risk factors and detailed toxicity, and the lack of central radiologic review.

Conclusions

TEMSR is an effective and largely well-tolerated treatment alternative for metastatic RCC patients in daily clinical practice, irrespective of the patient's age, histologic RCC subtype, or line of treatment.     

Salvianolic acid B protects human endothelial progenitor cells against oxidative stress-mediated dysfunction by modulating Akt/mTOR/4EBP1, p38 MAPK/ATF2, and ERK1/2 signaling pathways

The vascular endothelium is specifically sensitive to oxidative stress, and this is one of the mechanisms that causes widespread endothelial dysfunction in most cardiovascular diseases and disorders. Protection against reactive oxygen species (ROS)-mediated oxidative damage via antioxidant mechanisms is essential for tissue maintenance and shows therapeutic potential for patients suffering from cardiovascular and metabolic disorders. Salvianolic acid B (SalB), a natural bioactive component known from Traditional Chinese Medicine, has been reported to exert cellular protection in various types of cells. However, the underlying mechanisms involved are not fully understood. Here, we showed that SalB significantly promoted the migratory and tube formation abilities of human bone marrow derived-endothelial progenitor cells (BM-EPCs) in vitro, and substantially abrogated hydrogen peroxide (H₂O₂)-induced cell damage. SalB down-regulated Nox4 and eNOS, as well as nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase expression upon H₂O₂ induction that in turn prevents oxidative-induced endothelial dysfunction. Moreover, SalB suppressed the Bax/Bcl-xL ratio and caspase-3 activation after H₂O₂ induction. Furthermore, our results provide mechanistic evidence that activation of the mTOR/p70S6K/4EBP1 pathways is required for both SalB-mediated angiogenic and protective effects against oxidative stress-induced cell injury in BM-EPCs. Suppression of MKK3/6-p38 MAPK-ATF2 and ERK1/2 signaling pathways by SalB significantly protected BM-EPCs against cell injury caused by oxidative stress via reduction of intracellular ROS levels and apoptosis. Taken together, by providing a mechanistic insight into the modulation of redox states in BM-EPCs by SalB, we suggest that SalB has a strong potential of being a new proangiogenic and cytoprotective therapeutic agent with applications in the field of endothelial injury-mediated vascular diseases.