Anti-apoptotic effect of Suxiao Jiuxin Pills against hypoxia-induced injury through PI3K/Akt/GSK3β pathway in HL-1 cardiomyocytes

Background

Suxiao Jiuxin Pill (SX), Chinese traditional medicine primarily consisting of tetramethylpyrazine and borneol, has been shown to protect against ischemic heart diseases. Nevertheless, the involved mechanism still remains unclear. The following study aimed to investigate the potential protective effect and molecular mechanisms of SX on apoptosis in HL-1 cardiomyocytes.

Inhibition of Phosphodiesterase 4 by FCPR16 Protects SH-SY5Y Cells against MPP+-Induced Cell Death through Activating cAMP/PKA/CREB and Epac/Akt Signaling Pathways

Background: Phosphodiesterase 4 (PDE4) is a promising target for the treatment of Parkinson's disease (PD). However, the underlying mechanism has not yet been well elucidated. Additionally, most of current PDE4 inhibitors produce severe nausea and vomiting response in patients, which limit their clinical application. FCPR16 is a novel PDE4 inhibitor with little emetic potential. In the present study, the neuroprotective effect and underlying mechanism of FCPR16 against cellular apoptosis induced by 1-methyl-4-phenylpyridinium (MPP+) were examined in SH-SY5Y cells and primary cultured neurons. Methods: CCK-8 assay, Hoechst staining, lactate dehydrogenase release and flow cytometry were used to study the protective effect of FCPR16 against cell damage caused by MPP+. Mitochondrial membrane potential (Δψm) was measured by JC-1 staining. The extent of oxidation was evaluated using Cell ROXs Deep Red Reagent and malonaldehyde (MDA) kit. Pretreatments with various pathway inhibitors were used to investigate the possible pathways involved in the protection of FCPR16. The phosphorylated and total levels of various proteins were analyzed by Western blot. Results: FCPR16 (12.5–50 μM) dose-dependently reduced MPP+-induced loss of cell viability, accompanied by reductions in nuclear condensation and lactate dehydrogenase release. The level of cleaved caspase 3 and the ratio of Bax/Bcl-2 were also decreased after treatment with FCPR16 in MPP+-treated cells. Furthermore, FCPR16 (25 μM) significantly suppressed the accumulation of reactive oxygen species (ROS), prevented the decline of Δψm and attenuated the expression of MDA level. Further studies disclosed that FCPR16 enhanced the levels of cAMP and the exchange protein directly activated by cAMP (Epac) in SH-SY5Y cells. Western blotting analysis revealed that FCPR16 increased the phosphorylation of cAMP response element-binding protein (CREB) and protein kinase B (Akt) down-regulated by MPP+ in SH-SY5Y cells. Moreover, the inhibitory effects of FCPR16 on the production of ROS and Δψm loss could be blocked by PKA inhibitor H-89 and Akt inhibitor KRX-0401. We also found that MPP+ induced a dose-dependent apoptosis in cultured neurons, and 500 μM MPP+ caused an approximately 50% loss of cortical neurons, while treatment with FCPR16 reversed the toxic effect of MPP+ and enhanced the cell viability in a dose-dependent manner. Conclusions: These results suggest that FCPR16 attenuates MPP+-induced dopaminergic degeneration via lowering ROS and preventing the loss of Δψm in SH-SY5Y cells. Mechanistically, cAMP/PKA/CREB and Epac/Akt signaling pathways are involved in these processes.     

红花提取物对肝纤维化大鼠肝线粒体的作用

目的 探讨红花提取物对肝纤维化大鼠肝细胞线粒体的保护作用。方法 二乙基亚硝胺诱导大鼠肝纤维化模型,实验组口服红花提取物,分离各组肝组织细胞线粒体,观察肝细胞线粒体形态学改变,检测MDA和SOD在肝细胞线粒体中的水平。观察线粒体膜势能和线粒体ATP的水平改变,并观察线粒体的呼吸功能变化,以研究红花提取物对肝纤维化大鼠肝细胞线粒体是否具有保护作用。结果 正常组大鼠肝线粒体排列整齐、形态正常,对照组的大鼠线粒体肿胀且形态不规则,边界不清晰,且大小不一致,而实验组线粒体的肿胀、结构不清晰、大小不一等情况有明显改善;肝纤维化大鼠肝细胞线粒体中MDA的水平明显升高,而SOD的含量明显下降,红花提取物处理则能明显降低线粒体MDA的水平,并提高SOD的含量;与正常组相比,肝纤维化大鼠的线粒体膜势能明显降低,而红花提取物处理能够提高线粒体膜势能;大鼠由于肝纤维化可加重消耗肝细胞线粒体中的ATP,而红花提取物能明显减少大鼠线粒体中的ATP消耗。与之一致的是,实验组大鼠线粒体中的磷氧比明显高于对照组。结论 红花提取物能明显降低大鼠肝纤维化诱导的肝细胞线粒体氧化应激。能维持肝细胞线粒体ATP水平、呼吸控制率及磷氧比来保护线粒体的功能。     

核苷类似物对小鼠中枢神经线粒体毒性研究

目的探讨长期使用核苷类似物是否产生中枢神经元线粒体损伤。方法取7周龄Balb/C小鼠40只,分为4组,每组10只。实验组每天分别喂饲司它夫定（D4T）50 mg/kg、齐多夫定（AZT）100 mg/kg和拉米夫定（3TC）50 mg/kg,每周5 d,连续16周;对照组喂服双蒸水。通过激光单细胞捕获技术抓取小鼠大脑皮层神经元,每组200个细胞,通过实时定量PCR观察线粒体DNA（mtDNA）含量变化。结果 COXⅡ基因扩增显示,喂饲核苷类似物可明显减低小鼠大脑皮层神经元mtDNA拷贝数,其中D4T组减少至对照组的（22.2±3.2）%,AZT组减少至对照组的（53.6±7.1）%,3TC组减少至对照组的（34.6±8.2）%。同时,与对照组相比,ND4基因扩增显示,mtDNA主环拷贝数明显减低,D4T、AZT、3TC组分别为对照组的（25.2±7.3）%、（46.3±9.1）%和（42.3±7.4）%。与对照组比较,差异均有统计学意义（P﹤0.05）。但是,3组ND1基因扩增显示,mtDNA小环拷贝数依次为对照组的（67.7±5.2）%、（53.5±9.2）%和（94.4±8.3）%。AZT与对照组比较,mtDNA小环拷贝数明显降低（P﹤0.05）,其他两组与对照组比较则无明显变化。结论长期使用核苷类似物可产生小鼠神经元mtDNA损伤,且以主环缺失为主。     

Measurement of the apparent diffusion coefficient in paediatric mitochondrial encephalopathy cases and a comparison of parenchymal changes associated with the disease using follow-up diffusion coefficient measurements

Objectives

To reveal the contribution of MRI and diffusion-weighted imaging (DWI) to the diagnosis of mitochondrial encephalopathy (ME) and to evaluate the parenchymal changes associated with this disease in the involved parenchymal areas using the apparent diffusion coefficient (ADC) parameter.

Methods

Ten patients who had undergone MRI and DWI analysis with a pre-diagnosis of neurometabolic disease, and who were subsequently diagnosed with ME in laboratory and/or genetic studies, were included in our study. ADC values were compared with a control group composed of 20 patients of similar age with normal brains. Evaluations involved measurements made in 20 different areas determined on the ADC map. The dominance or contribution of ADC coefficient measurements to the conventional sequences was compared with the controls.

Results

In the first examination, an increase in both diffusion and ADC values was detected in six cases and diffusion restriction and a decrease in ADC values in three patients. While an increase in both diffusion and ADC values was demonstrated in four cases, there was diffusion restriction and a decrease in ADC values in three cases in the control examinations.

Conclusions

DWI provides information that complements conventional MRI sequences in the diagnosis of ME.     

Does blood flow restriction result in skeletal muscle damage? A critical review of available evidence

Blood flow restriction (BFR) alone or in combination with exercise has been shown to result in muscle hypertrophy and strength gain across a variety of populations. Although there are numerous studies in the literature showing beneficial muscular effects following the application of BFR, questions have been raised over whether BFR may lead to or even increase the incidence of muscle damage. The purpose of this review is to examine the proposed mechanisms behind muscle damage and critically review the available BFR literature. The available evidence does not support the hypothesis that BFR in combination with low‐intensity exercise increases the incidence of muscle damage. Instead, the available literature suggests that minimal to no muscle damage is occurring with this type of exercise. This conclusion is drawn from the following observations: (a) no prolonged decrements in muscle function; (b) no prolonged muscle swelling; (c) muscle soreness ratings similar to a submaximal low load control; and (d) no elevation in blood biomarkers of muscle damage.     

Treatment with Laevo (l)-carnitine reverses the mitochondrial function of human embryos

PurposeLaevo (l)-carnitine plays important roles in reducing the cytotoxic effects of free fatty acids by forming acyl-carnitine and promoting beta-oxidation, leading to alleviation of cell damage. Recently, the mitochondrial functions in morula has been shown to decrease with the maternal age. Here, we assessed the effect of l-carnitine on mitochondrial function in human embryos and embryo development.MethodsTo examine the effect of l-carnitine on mitochondrial function in morulae, 38 vitrified–thawed embryos at the 6–11-cell stage on day 3 after ICSI were donated from 19 couples. Each couple donated two embryos. Two siblings from each couple were divided randomly into two groups and were cultured in medium with or without 1 mM l-carnitine. The oxygen consumption rates (OCRs) were measured at morula stage. The development of 1029 zygotes cultured in medium with or without l-carnitine was prospectively analyzed.ResultsAddition of l-carnitine to the culture medium significantly increased the OCRs of morulae and improved the morphologically-good blastocyst formation rate per zygote compared with sibling embryos. Twenty healthy babies were born from embryos cultured in l-carnitine-supplemented medium after single embryo transfers.Conclusion(s)l-carnitine is a promising culture medium supplement that might be able to counteract the decreased mitochondrial function in human morula stage embryos.     

卵巢细胞线粒体动力学变化与多囊卵巢综合征

多囊卵巢综合征（polycystic ovary syndrome,PCOS）是常见的女性内分泌疾病之一。PCOS患者颗粒细胞中调节线粒体动力学平衡关键因子表达水平的异常,提示PCOS患者卵巢细胞清除功能异常,线粒体的能力降低。卵巢细胞中异常线粒体的积聚不仅会影响细胞的胰岛素敏感性及甾体激素合成能力,还会直接降低卵泡细胞维持卵子发育的能力。而卵细胞中线粒体功能异常则会对卵子的发育潜能产生直接的负面影响。PCOS患者卵巢细胞胰岛素信号通路异常可能干扰卵巢细胞及卵细胞的线粒体动力学平衡,引起功能异常线粒体在细胞内积累,进而引起细胞内线粒体功能的异常。推测PCOS患者卵巢细胞线粒体动力学平衡的异常与PCOS患者生殖功能异常之间存在密切联系,并可能是PCOS患者胰岛素抵抗与卵巢功能异常的关键节点,但针对这一机制开发的临床治疗方案还有待进一步的深入研究。     

2-甲氧基雌二醇诱导K562细胞凋亡的机制研究

目的探讨2-甲氧基雌二醇(2-ME)对K562细胞的凋亡诱导效应及其作用机制。方法使用不同浓度2-ME(0,5,10,20,40μmol/L)作用于K562细胞,48 h后用流式细胞术检测2-ME作用后K562细胞的凋亡率的变化;用western blot方法检测2-ME作用48 h后K562细胞Bcl-2、Bax和Caspase-3蛋白的表达。结果 (1)2-ME在5~40μmol/L浓度范围内作用48 h对K562细胞有凋亡诱导作用,与对照组比较差异有显著性(P<0.05),这种作用呈剂量依赖关系;(2)2-ME作用48 h后,K562细胞Bcl-2蛋白的表达较对照组减少,差异有显著性(P<0.05),而Bax和Caspase-3表达较对照组增高,差异有显著性(P<0.05)。结论 2-ME可能通过线粒体途径诱导K562白血病细胞凋亡。     

盆腔器官脱垂患者外周血和盆底组织中mtDNA和mtDNA~(4977)的含量及意义

目的:探讨盆腔器官脱垂(POP)患者外周血和盆底不同组织中线粒体DNA(mtDNA)及mtDNA 4977bp缺失(mtDNA4977)的含量变化与POP发生发展之间的关系。方法:采用实时定量PCR法分别检测26例POP患者和21例非POP患者外周血、骶韧带、阴道前后壁组织中mtDNA和mtDNA4977的相对含量。结果:(1)mtDNA在骶韧带中的含量,POP组明显低于非POP组,差异有统计学意义(P<0.05);而mtDNA在POP患者的外周血、阴道前壁和后壁中的含量,与非POP组比较,差异均无统计学意义(P>0.05)。mtDNA4977在POP患者的外周血、骶韧带、阴道前壁和后壁中的含量均显著高于非POP患者,差异有统计学意义(P<0.05)。无论mtDNA还是mtDNA4977,其含量在阴道前壁和后壁之间均无显著差异(P>0.05)。(2)随着POP程度不断加重(分析0到Ⅲ期POP),发现骶韧带中mtDNA含量呈下降趋势,而外周血、阴道前壁和后壁中此趋势不明显;在外周血、骶韧带、阴道前壁和后壁中mtDNA4977的比例却显著增加(P<0.05)。(3)POP患者外周血、骶韧带及阴道壁中mtDNA与mtDNA4977含量均无明显相关性(P>0.05)。mtDNA在POP患者外周血和骶韧带之间呈正相关(P<0.05),而mtDNA4977在POP患者外周血和骶韧带之间无显著相关性(P>0.05)。结论:mtDNA的消耗和mtDNA4977比例增加可能在POP分子水平的发病机制中起重要作用。