Significance of NMDA receptor-related glutamatergic amino acid levels in peripheral blood of patients with schizophrenia

Hypo-function of N-methyl d-aspartate (NMDA) receptors is strongly involved in the brain pathophysiology of schizophrenia. Several excitatory amino acids, such as endogenous glutamate, glycine, serine and alanine, which are involved in glutamate neurotransmission via NMDA receptors, were studied to further understand the pathophysiology of schizophrenia and to find a biological marker for this disease, particularly in peripheral blood. In this literature review, we connect several earlier clinical studies and several studies of excitatory amino acid levels in peripheral blood in a historical context. Finally, we join these results and our previous studies, the Juntendo University Schizophrenia Projects (JUSP), which investigated plasma glutamatergic amino acid levels in detail, and considered whether these amino acid levels may be diagnostic, therapeutic, or symptomatic biological markers. This review concludes that peripheral blood levels of endogenous glycine and alanine could be a symptomatic marker in schizophrenia, while peripheral blood levels of exogenous glycine and alanine in augmentation therapies could be therapeutic markers. Noteworthy peripheral blood levels of endogenous d-serine could reflect its brain levels, and may prove to be a useful diagnostic and therapeutic marker in schizophrenia. In addition, measurements of new endogenous molecules, such as glutathione, are promising. Finally, for future therapies with glutamatergic agents still being examined in animal studies, the results of these biological marker studies may lay the foundation for the development of next-generation antipsychotics.     

Combination of multichannel single‐voxel MRS signals using generalized least squares

Purpose:

To propose using the generalized least square (GLS) algorithm for combining multichannel single‐voxel magnetic resonance spectroscopy (MRS) signals.

Materials and Methods:

Phantom and in vivo brain MRS experiments on a 7 T scanner equipped with a 32‐channel receiver coil, as well as Monte Carlo simulations, were performed to compare the coefficient of variation (CV) of the GLS method with those of two recently reported spectral combination methods.

Results:

Compared to the two existing methods, the GLS method significantly reduced CV values for the simulation, phantom, and in vivo experiments.

Conclusion:

The GLS method can lead to improved precision of peak quantification. J. Magn. Reson. Imaging 2013;37:1445–1450. © 2012 Wiley Periodicals, Inc.     

Simulated digestion of dried leaves of Artemisia annua consumed as a treatment (pACT) for malaria

Ethnopharmacological relevance

Artemisinin (AN) is produced by Artemisia annua, a medicinal herb long used as a tea infusion in traditional Chinese medicine to treat fever; it is also the key ingredient in current artemisinin-based combination therapies (ACTs) effective in treating malaria. Recently we showed that dried leaves from the whole plant Artemisia annua that produces artemisinin and contains artemisinin-synergistic flavonoids seem to be more effective and less costly than ACT oral malaria therapy; however little is known about how digestion affects release of artemisinin and flavonoids from dried leaves.

Material and methods

In the current study we used a simulated digestion system to determine how artemisinin and flavonoids are released prior to absorption into the bloodstream. Various delivery methods and staple foods were combined with dried leaves for digestion in order to investigate their impact on the bioavailability of artemisinin and flavonoids. Digestate was recovered at the end of the oral, gastric, and intestinal stages, separated into solid and liquid fractions, and extracted for measurement of artemisinin and total flavonoids.

Results

Compared to unencapsulated digested dried leaves, addition of sucrose, various cooking oils, and rice did not reduce the amount of artemisinin released in the intestinal liquid fraction, but the amount of released flavonoids nearly doubled. When dried leaves were encapsulated into either hydroxymethylcellulose or gelatin capsules, there was >50% decrease in released artemisinin but no change in released flavonoids. In the presence of millet or corn meal, the amount of released artemisinin declined, but there was no change in released flavonoids. Use of a mutant Artemisia annua lacking artemisinin showed that the plant matrix is critical in determining how artemisinin is affected during the digestion process.

Conclusions

This study provides evidence showing how both artemisinin and flavonoids are affected by digestion and dietary components for an orally consumed plant delivered therapeutic and that artemisinin delivered via dried leaves would likely be more bioavailable if provided as a tablet instead of a capsule.     

circ_0000619通过调控miR-595/GLS轴对食管鳞状细胞癌细胞增殖及谷氨酰胺代谢的影响

目的:探讨circ_0000619/miR-595/GLS轴对人食管鳞状细胞癌（esophageal squamous cell carcinoma,ESCC）KYSE150细胞增殖、迁移、侵袭和谷氨酰胺代谢的影响及其可能的机制。方法:采用qPCR法检测KYSE150细胞中circ_0000619、miR-595、谷氨酰胺酶（glutaminase,GLS）mRNA等表达水平,Western blot检测KYSE150细胞中GLS蛋白的表达情况,使用细胞计数试剂盒-8（cell counting kit-8,CCK-8）试剂盒、Transwell法分别检测KYSE150细胞增殖、迁移及侵袭能力,使用相应的检测试剂盒检测KYSE150细胞谷氨酰胺消耗、谷氨酸产生及ATP产生水平,利用生物信息学分析技术及双荧光素酶报告基因实验分析并检测circ_0000619、miR-595与GLS mRNA之间的相互作用关系。结果:circ_0000619在ESCC细胞系中呈现高表达,其亲本基因DENND4A mRNA在食管癌组织中呈高表达（P<0.01）;敲减circ_0000619显著抑制KYSE150细胞的增殖、侵袭和迁移能力（P<0.01）,并显著抑制KYSE150细胞的谷氨酰胺消耗、谷氨酸及ATP产生水平（P<0.01）;敲减circ_0000619显著上调miR-595表达（P<0.01）,抑制GLS mRNA（P<0.01）及蛋白的表达;双荧光素酶报告基因实验显示在KYSE150细胞中,circ_0000619与miR-595存在靶向结合、miR-595与GLS存在靶向结合（P<0.01）。circ_0000619敲低显著降低了KYSE150细胞谷氨酰胺代谢和细胞增殖,并且这些作用被miR-595抑制或GLS过表达部分逆转。结论:circ_0000619能通过靶向调控miR-595/GLS轴增强ESCC细胞谷氨酰胺代谢及细胞增殖,并可能成为潜在的ESCC治疗靶点。     

Targeting glutamine utilization to block metabolic adaptation of tumor cells under the stress of carboxyamidotriazole-induced nutrients unavailability

Tumor cells have unique metabolic programming that is biologically distinct from that of corresponding normal cells. Resetting tumor metabolic programming is a promising strategy to ameliorate drug resistance and improve the tumor microenvironment. Here, we show that carboxyamidotriazole (CAI), an anticancer drug, can function as a metabolic modulator that decreases glucose and lipid metabolism and increases the dependency of colon cancer cells on glutamine metabolism. CAI suppressed glucose and lipid metabolism utilization, causing inhibition of mitochondrial respiratory chain complex I, thus producing reactive oxygen species (ROS). In parallel, activation of the aryl hydrocarbon receptor (AhR) increased glutamine uptake via the transporter SLC1A5, which could activate the ROS-scavenging enzyme glutathione peroxidase. As a result, combined use of inhibitors of GLS/GDH1, CAI could effectively restrict colorectal cancer (CRC) energy metabolism. These data illuminate a new antitumor mechanism of CAI, suggesting a new strategy for CRC metabolic reprogramming treatment.     

灵芝孢子粉对HepG2细胞生长增殖和生长周期的影响

目的:观察灵芝孢子粉对人肝癌细胞株HepG2细胞生长增殖和生长周期的影响,并初步探讨其作用机制。方法:采用MTT比色法研究灵芝孢子粉对HepG2细胞生长抑制作用;通过流式细胞仪检测DNA含量,分析细胞周期的分布。结果:MTT实验结果表明高剂量的灵芝孢子粉对HepG2细胞具有直接的抑制作用,并呈剂量和时间依赖性,2500μg/m l的灵芝孢子粉作用于HepG2细胞72h后,对细胞生长的抑制率最高可达51.4%;流式细胞术实验结果表明,灵芝孢子粉浓度为3mg/m l时,可使肿瘤细胞生长G2期减小,浓度为6 mg/m l时,可使HepG2细胞出现明显的凋亡峰。结论:灵芝孢子粉具有直接抑制肿瘤细胞生长的作用,并可作用于细胞周期的G2期,高剂量的灵芝孢子粉还可使肿瘤细胞发生凋亡。