Oleanolic Acid Induces Apoptosis in Human Leukemia Cells through Caspase Activation and Poly（ADP-ribose） Polymerase Cleavage

It has been shown that Fructus Ligustri Lucidi （FLL）, a promising traditional Chinese medicine, can inhibit the growth of tumors. However, the effective component and molecular mechanism of FLL act to inhibit tumor proliferation are unclear. In this study, we demonstrated that oleanolic acid （OA）, a principal chemical component of FLL, inhibited the proliferation of human leukemia HL60 cells in culture. MTT assay showed that treatment of HL60 cells with FLL crude extracts or OA dramatically blocked the growth of target tumor cell in a time- and dose-dependent manner. Morphological changes of the nuclei and DNA fragmentation showed that apoptotic cell death occurred in the HL60 cells after treating with FLL extracts （20 mg/ml） or OA （3.65×10^-2 mg/ml）. Furthermore, flow cytometry assay showed that treatment of HL60 cells with FLL or OA caused an increased accumulation of G1 and sub-G1 subpopulations. Western blot analysis showed that caspase-9 and caspase-3 were activated, accompanied by the cleavage of poly （ADP-ribose） polymerase （PARP） in the target cells during FLL- or OA-induced apoptosis, These results suggest that OA acts as the effective component of FLL by exerting its cytotoxicity towards target tumor cells through activation of caspases and cleavage of PARP.     

Development and validation of a LC-MS/MS method for the determination of viaminate in human plasma

A sensitive and specific method for determination of viaminate in human plasma by using high-performance liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS) was developed in this study. The plasma samples were simply deproteinated, extracted, evaporated, and then reconstituted in 200 microl of methanol prior to analysis. Chromatographic separation was carried out on a Shimadzu VP-ODS column (250 mm x 2.0 mm, 5 microm) with a mobile phase of methanol-water (95:5, v/v) at a flow rate of 0.2 ml/min. Quantification was performed in the negative-ion electrospray ionization mode by selected ion monitoring of the product ions at m/z 164 for viaminate and m/z 109 for testosterone propionate which was used as the internal standard. The corresponding parent ions were m/z 446 and m/z 345. A linear calibration curve was observed within the concentration range of 0.10-200 ng/ml. The lowest limit of quantitation (LLOQ) was 0.1 ng/ml. The extraction-efficiency at three concentrations was 100.7, 93.6, and 99.7%. Practical utility of this new LC-MS/MS method was confirmed in pilot pharmacokinetic studies in humans following oral administration.     

Comparative Endocranial Anatomy,Encephalization, and Phylogeny of Notoungulata (Placentalia,Mammalia)

Journal of Mammalian Evolution - Cranial endocasts are one of the most direct tools available to obtain information about the endocranial cavity of fossil mammals, but few anatomical comparisons...     

Two stochastic processes shape diverse senescence patterns in a single‐cell organism

Despite advances in aging research, a multitude of aging models, and empirical evidence for diverse senescence patterns, understanding of the biological processes that shape senescence is lacking. We show that senescence of an isogenic Escherichia coli bacterial population results from two stochastic processes. The first process is a random deterioration process within the cell, such as generated by random accumulation of damage. This primary process leads to an exponential increase in mortality early in life followed by a late age mortality plateau. The second process relates to the stochastic asymmetric transmission at cell fission of an unknown factor that influences mortality. This secondary process explains the difference between the classical mortality plateaus detected for young mothers’ offspring and the near nonsenescence of old mothers’ offspring as well as the lack of a mother–offspring correlation in age at death. We observed that lifespan is predominantly determined by underlying stochastic stage dynamics. Surprisingly, our findings support models developed for metazoans that base their arguments on stage‐specific actions of alleles to understand the evolution of senescence. We call for exploration of similar stochastic influences that shape aging patterns beyond simple organisms.     

Apoptosis in HepaRG and HL-7702 cells inducted by polyphyllin II through caspases activation and cell-cycle arrest

Rhizoma Paridis, a traditional Chinese medicine, has shown promise in cancer prevention and therapy. Polyphyllin II is one of the most significant saponins in Rhizoma Paridis and it has toxic effects on kinds of cancer cells. However, our results in this study proved that the polyphyllin II has hepatotoxicity in vitro through caspases activation and cell-cycle arrest. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide results indicated polyphyllin II inhibited proliferation, induced apoptosis in HepaRG cells and HL-7702 cells and showed a concentration and time-dependent. Then, we selected the innovative cell model-HepaRG cells to explore the mechanism of hepatotoxicity. Our data showed the reactive oxygen species (ROS) increased and the mitochondrial membrane potential decreased in HepaRG cells after administration of polyphyllin II. Besides, with the increase of concentration, the release of lactate dehydrogenase increased and the S phase of the cell cycle was arrested. Nevertheless, when pretreatment with antioxidant N-acetylcysteine, apoptotic cells decreased significantly, inhibited the production of ROS and improved the decrease of membrane potential in HepaRG cells. Moreover, polyphyllin II treatment increased levels of Fas, Bax, cytochrome c, activated caspase-3, -8, -9, cleaved poly(ADP-ribose) polymerase and decreased Bcl-2 expression levels. Finally, we identified two signal pathways of apoptosis induced by polyphyllin II including the death receptor pathway and the mitochondria pathway. This study confirmed the hepatotoxicity of the polyphyllin II in vitro, which has never been discovered and gave a wake-up call for the clinical application of Rhizoma Paridis.     

天山一号冰川表面冰尘和底部沉积层中可培养酵母菌系统发育类群的分布及生态生理特征

【目的】揭示乌鲁木齐河源天山1号冰川表面冰尘(CS)和底部沉积层(DS)可培养酵母菌系统发育类群及其结构组成差异,分析低温酵母菌代表菌株之间的生态、生理生化特性。【方法】利用4种培养基分离天山1号冰川可培养酵母菌,采用ITS基因序列分析确定菌种的系统进化地位。对分离菌株的最适生长温度、耐盐性和产酶等生态、生理学特性进行分析。【结果】从冰尘和底部沉积层中共分离出152株酵母菌菌株,通过ITSrRNA基因序列的NCBI比对和Rep-PCR指纹分型,结果表明酵母菌类群包括担子菌门(Basidiomycota)和子囊菌(Ascomycota),分属于14个属26种,其中担子菌门柄锈菌亚门(Pucciniomycotina)88株、伞菌亚门(Agariomycotina)24株,子囊菌门40株,冰川广布酵母菌Vishniacozyma victoriae为优势菌株(占比21.84%)。17种酵母的最适生长温度为15°C、2种为10°C、6种为20°C。25株代表酵母菌株产酶分析显示,产脂肪酶、淀粉酶、蛋白酶菌株分别为11株、11株、5株,6株3种酶都不产。【结论】天山1号冰川冰尘及底部沉积层可培养低温酵母系统发育类群结构存在差异,产低温酶活性高、稳定性好,为今后冰川低温酵母菌的研究提供有价值的数据支持。     

Front Cover Image,Volume 116, Number 11, November 2019

CRISPR/Cas9-guided cytidine deaminase enables C:G to T:A base editing in bacterial genome without introduction of lethal double-stranded DNA break, supplement of foreign DNA template, or dependence on inefficient homologous recombination. However, limited by genome-targeting scope, editing window, and base transition capability, the application of base editing in metabolic engineering has not been explored. Herein, four Cas9 variants accepting different protospacer adjacent motif (PAM) sequences were used to increase the genome-targeting scope of bacterial base editing. After a comprehensive evaluation, we demonstrated that PAM requirement of bacterial base editing can be relaxed from NGG to NG using the Cas9 variants, providing 3.9-fold more target loci for gene inactivation in Corynebacterium glutamicum. Truncated or extended guide RNAs were employed to expand the canonical 5-bp editing window to 7-bp. Bacterial adenine base editing was also achieved with Cas9 fused to adenosine deaminase. With these updates, base editing can serve as an enabling tool for fast metabolic engineering. To demonstrate its potential, base editing was used to deregulate feedback inhibition of aspartokinase via amino acid substitution for lysine overproduction. Finally, a user-friendly online tool named gBIG was provided for designing guide RNAs for base editing-mediated inactivation of given genes in any given sequenced genome ( www.ibiodesign.net/gBIG ).     

Length–weight relationships for 15 fish species from the Three Gorges Reservoir

The length–weight relationships (LWRs) for 15 fish species from the Three Gorges Reservoir (TGR) were described in this paper. Specimens were collected using gill nets (mesh size: 6, 8, 10, 12 cm), cage net (mesh size: 1 cm), benthic fyke net (mesh size: 1 cm), hook longlines (80 m long, 3 barbless hooks per meter line) and electrofishing (power: 1,500 w; distance of electrodes: 1–2 m; water depth: 0.2–1.0 m; water area: 1–2 m²; catch by dip net [mesh size: 0.4 cm]) at four sections of the TGR, monthly in June–August and October–November in 2017 and 2018. The first LWR reference for Zacco acutipinnis (Bleeker, 1871), Discogobio brachyphysallidos Huang, 1989, Squalidus nitens (Günther, 1873), Leptobotia pellegrini Fang, 1936, Sinibotia reevesae (Chang, 1944), Pseudobagrus tenuifurcatus (Nichols, 1931), Pseudobagrus medianalis (Regan, 1904), Liobagrus marginatoides (Wu, 1930), Glyptothorax fokiensis (Rendahl, 1925), and Ctenogobius szechuanensis (Liu, 1940) and new maximum total length for 12 species are provided.     

Dependence of artesunate on long noncoding RNA-RP11 to inhibit epithelial-mesenchymal transition of hepatocellular carcinoma

As a first line medicine for malaria treatment, artesunate (ART) also shows antitumor potential. However, little is known about the effect of ART on the cancer cell epithelial-mesenchymal transition (EMT). In this study, we found that ART inhibited cell growth in SK-HEP1 and SM7721 hepatocellular carcinoma cell lines. A microarray was used to identify differentially expressed protein-coding RNAs (pcRNA) and long noncoding RNAs (lncRNA) between SK-HEP1 cells with and without ART treatment. A differentially expressed lncRNA—RP11, the most related to the EMT of liver cancer cells—RP11 was identified by abioinformatics method Overexpressing and silencing assays were used to verify the role of RP11 in cancer cell EMT. The levels of RP11- and EMT-related genes in liver cancer samples from 75 patients were detected by using qualitative polymerase chain reaction or immunohistochemistry. We identified 1334 pcRNAs and 1670 lncRNA with differential expression induced by ART. ART inhibits EMT, proliferation, migration, invasion, and adhesion of liver cancer cells. RP11 depresses the inhibitory effect of ART on cancer cell EMT. The level of RP11 is associated with cancer cell EMT and metastasis and survival rate of the patient. These data suggest that RP11-linking ART and cancer cell EMT are important for ART-inhibited metastasis of liver cancer.