Tibolone Pre-Treatment Ameliorates the Dysregulation of Protein Translation and Transport Generated by Palmitic Acid-Induced Lipotoxicity in Human Astrocytes: A Label-Free MS-Based Proteomics and Network Analysis

Excessive accumulation and release of fatty acids (FAs) in adipose and non-adipose tissue are characteristic of obesity and are associated with the leading causes of death worldwide. Chronic exposure to high concentrations of FAs such as palmitic acid (pal) is a risk factor for developing different neurodegenerative diseases (NDs) through several mechanisms. In the brain, astrocytic dysregulation plays an essential role in detrimental processes like metabolic inflammatory state, oxidative stress, endoplasmic reticulum stress, and autophagy impairment. Evidence shows that tibolone, a synthetic steroid, induces neuroprotective effects, but its molecular mechanisms upon exposure to pal remain largely unknown. Due to the capacity of identifying changes in the whole data-set of proteins and their interaction allowing a deeper understanding, we used a proteomic approach on normal human astrocytes under supraphysiological levels of pal as a model to induce cytotoxicity, finding changes of expression in proteins related to translation, transport, autophagy, and apoptosis. Additionally, tibolone pre-treatment showed protective effects by restoring those same pal-altered processes and increasing the expression of proteins from cell survival processes. Interestingly, ARF3 and IPO7 were identified as relevant proteins, presenting a high weight in the protein-protein interaction network and significant differences in expression levels. These proteins are related to transport and translation processes, and their expression was restored by tibolone. This work suggests that the damage caused by pal in astrocytes simultaneously involves different mechanisms that the tibolone can partially revert, making tibolone interesting for further research to understand how to modulate these damages.     

高纯度乌桕脂棕榈酸、油酸制取工艺研究

为满足日益增长的高科技市场对高纯度棕榈酸、油酸的迫切需求,充分利用中国乌桕脂的资源优势和化学组成特点,研究并提出“无催化剂分批压热釜水解,溶剂结晶－精馏、柱层析”法。原料乌桕脂水解率９７．３６％。高纯度棕榈酸纯度９８．７７％,收率９０％。高纯度油酸纯度９８．０３％,收率９２％。高纯度水解甘油纯度９８％,收率８９％     

Sonication Assisted Three Phase Partitioning for the Extraction of Palmitic Acid and Elaidic Acid from Cassia sophera Linn.

Ultrasound assisted three phase partitioning (UATPP) has been explored for the extraction of palmitic acid (PA) and elaidic acid (EA) from Cassia sophera Linn. seed powder, and the process were optimized. Ultrasound was applied with TPP to improve the yield with operating frequencies of 25 and 40 kHz and at a power 200 W. The yield of PA and EA was 0.25 ± 0.005% and 0.26 ± 0.006%, respectively, with TPP. The yield was found 0.31 ± 0.002% and 0.32 ± 0.016%, with UATPP at 40 kHz and 180 W power. UATPP was found to be an effective technique.     

Eicosapentaenoic Acid Protects against Palmitic Acid-Induced Endothelial Dysfunction via Activation of the AMPK/eNOS Pathway

Recent studies have shown that free fatty acids are associated with chronic inflammation, which may be involved in vascular injury. The intake of eicosapentaenoic acid (EPA) can decrease cardiovascular disease risks, but the protective mechanisms of EPA on endothelial cells remain unclear. In this study, primary human umbilical vein endothelial cells (HUVECs) treated with palmitic acid (PA) were used to explore the protective effects of EPA. The results revealed that EPA attenuated PA-induced cell death and activation of apoptosis-related proteins, such as caspase-3, p53 and Bax. Additionally, EPA reduced the PA-induced increase in the generation of reactive oxygen species, the activation of NADPH oxidase, and the upregulation of inducible nitric oxide synthase (iNOS). EPA also restored the PA-mediated reduction of endothelial nitric oxide synthase (eNOS) and AMP-activated protein kinase (AMPK) phosphorylation. Using AMPK siRNA and the specific inhibitor compound C, we found that EPA restored the PA-mediated inhibitions of eNOS and AKT activities via activation of AMPK. Furthermore, the NF-κB signals that are mediated by p38 mitogen-activated protein kinase (MAPK) were involved in protective effects of EPA. In summary, these results provide new insight into the possible molecular mechanisms by which EPA protects against atherogenesis via the AMPK/eNOS-related pathway.     

Identification and Functional Characterization of Acyl-ACP Thioesterases B (GhFatBs) Responsible for Palmitic Acid Accumulation in Cotton Seeds

In spite of increasing use in the food industry, high relative levels of palmitic acid (C16:0) in cottonseed oil imposes harmful effects on human health when overconsumed in the diet. The limited understanding of the mechanism in controlling fatty acid composition has become a significant obstacle for breeding novel cotton varieties with high-quality oil. Fatty acyl–acyl carrier protein (ACP) thioesterase B (FatBs) are a group of enzymes which prefer to hydrolyze the thioester bond from saturated acyl-ACPs, thus playing key roles in controlling the accumulation of saturated fatty acids. However, FatB members and their roles in cotton are largely unknown. In this study, a genome-wide characterization of FatB members was performed in allotetraploid upland cotton, aiming to explore the GhFatBs responsible for high accumulations of C16:0 in cotton seeds. A total of 14 GhFatB genes with uneven distribution on chromosomes were identified from an upland cotton genome and grouped into seven subfamilies through phylogenetic analysis. The six key amino acid residues (Ala, Trys, Ile, Met, Arg and Try) responsible for substrate preference were identified in the N-terminal acyl binding pocket of GhFatBs. RNA-seq and qRT-PCR analysis revealed that the expression profiles of GhFatB genes varied in multiple cotton tissues, with eight GhFatBs (GhA/D-FatB3, GhA/D-FatB4, GhA/D-FatB5, and GhA/D-FatB7) having high expression levels in developing seeds. In particular, expression patterns of GhA-FatB3 and GhD-FatB4 were positively correlated with the dynamic accumulation of C16:0 during cotton seed development. Furthermore, heterologous overexpression assay of either GhA-FatB3 or GhD-FatB4 demonstrated that these two GhFatBs had a high substrate preference to 16:0-ACP, thus contributing greatly to the enrichment of palmitic acid in the tested tissues. Taken together, these findings increase our understanding on fatty acid accumulation and regulation mechanisms in plant seeds. GhFatBs, especially GhA-FatB3 and GhD-FatB4, could be molecular targets for genetic modification to reduce palmitic acid content or to optimize fatty acid profiles in cotton and other oil crops required for the sustainable production of healthy edible oil.     

Oleogels Based on Palmitic Acid and Safflower Oil: Novel Formulations for Ocular Drug Delivery of Voriconazole

The gelation of the vegetable oils using fat crystals has gained significant attention in recent years. These formulations have been explored for food and pharmaceutical applications. The alteration in the properties of palmitic acid (20–40% w/w) and safflower oil oleogels is extensively studied at microscopic and macroscopic levels. The thermal and mechanical stability of the oleogels is improved when the proportion of the palmitic acid content is increased. However, under stress, the fat crystal network junction zones of the oleogels with higher proportions of palmitic acid undergo disruption. The changes in the properties of the oleogels are due to the alteration in the molecular packing, crystallite size, and lattice strain of the fat crystal network. The alteration in the properties is governed by the changes in the extent of inter‐ and intramolecular hydrogen bonding within the components of the oleogels. The oleogels can demonstrate the ability to deliver the drug, voriconazole, across the corneal tissue. Further, the prepared oleogels are biocompatible to murine fibroblast cells and do not elicit adverse reactions when instilled within the ocular sac of rabbits. The results suggest that the oleogels can be tried as ocular delivery vehicles. Practical Applications: The delivery of drug into the internal structure of the eye is a great challenge for the ophthalmologists. Usually no more than 1% of the drug can be delivered through conventional techniques. Various researchers have proposed the use of lipid‐based ocular drug delivery systems. Some of them include solid liquid nanoparticles, emulsions, and liposomes. However, the preparation of these formulations requires a tedious process. Keeping this in mind, it is proposed to synthesize oleogel as probable ocular drug delivery system.     

Palmitic Acid-Induced Neuron Cell Cycle G2/M Arrest and Endoplasmic Reticular Stress through Protein Palmitoylation in SH-SY5Y Human Neuroblastoma Cells

Obesity-related neurodegenerative diseases are associated with elevated saturated fatty acids (SFAs) in the brain. An increase in SFAs, especially palmitic acid (PA), triggers neuron cell apoptosis, causing cognitive function to deteriorate. In the present study, we focused on the specific mechanism by which PA triggers SH-SY5Y neuron cell apoptosis. We found that PA induces significant neuron cell cycle arrest in the G₂/M phase in SH-SY5Y cells. Our data further showed that G₂/M arrest is involved in elevation of endoplasmic reticular (ER) stress according to an increase in p-eukaryotic translation inhibition factor 2α, an ER stress marker. Chronic exposure to PA also accelerates beta-amyloid accumulation, a pathological characteristic of Alzheimer’s disease. Interestingly, SFA-induced ER stress, G₂/M arrest and cell apoptosis were reversed by treatment with 2-bromopalmitate, a protein palmitoylation inhibitor. These findings suggest that protein palmitoylation plays a crucial role in SFA-induced neuron cell cycle G₂/M arrest, ER stress and apoptosis; this provides a novel strategy for preventing SFA-induced neuron cell dysfunction.     

Effect of 9,12-Octadecadiynoic Acid on Neurobehavioral Development in Caenorhabditis elegans

Human breast milk lipids have major beneficial effects: they promote infant early brain development, growth and health. To identify the relationship between human breast milk lipids and infant neurodevelopment, multivariate analyses that combined lipidomics and psychological Bayley-III scales evaluation were utilized. We identified that 9,12-octadecadiynoic acid has a significantly positive correlation with infant adaptive behavioral development, which is a crucial neurodevelopment to manage risk from environmental stress. To further clarify the biological function of 9,12-octadecadiynoic acid in regulating neurodevelopment, Caenorhabditis elegans (C. elegans) was used as a model to investigate the effect of 9,12-octadecadiynoic acid on neurobehavioral development. Supplementation with 9,12-octadecadiynoic acid from the L1 to L4 stage in larvae affected locomotive behaviors and foraging ability that were not socially interactive, implying that 9,12-octadecadiynoic acid is involved in regulating the serotonergic neuronal ability. We found that supplementary 0.1 μM 9,12-octadecadiynoic acid accelerated the locomotive ability and foraging ability via increasing the expression of serotonin transporter mod-1. Antioxidant defense genes, sod-1, sod-3 and cyp-35A2 are involved in 9,12-octadecadiynoic acid-induced motor neuronal activity. Nevertheless, supplementary 9,12-octadecadiynoic acid at concentrations above 1 μM significantly attenuated locomotive behaviors, foraging ability, serotonin synthesis, serotonin-related gene expressions and stress-related gene expression, resulting in the decreased longevity of worms in the experiment. In conclusion, our study demonstrates the biological function of 9,12-octadecadiynoic acid in governing adaptive behavioral development.     

1H NMR-Based Metabolic Profiling Reveals the Effects of Fluoxetine on Lipid and Amino Acid Metabolism in Astrocytes

Fluoxetine, a selective serotonin reuptake inhibitor (SSRI), is a prescribed and effective antidepressant and generally used for the treatment of depression. Previous studies have revealed that the antidepressant mechanism of fluoxetine was related to astrocytes. However, the therapeutic mechanism underlying its mode of action in astrocytes remains largely unclear. In this study, primary astrocytes were exposed to 10 µM fluoxetine; 24 h post-treatment, a high-resolution proton nuclear magnetic resonance (¹H NMR)-based metabolomic approach coupled with multivariate statistical analysis was used to characterize the metabolic variations of intracellular metabolites. The orthogonal partial least-squares discriminant analysis (OPLS-DA) score plots of the spectra demonstrated that the fluoxetine-treated astrocytes were significantly distinguished from the untreated controls. In total, 17 differential metabolites were identified to discriminate the two groups. These key metabolites were mainly involved in lipids, lipid metabolism-related molecules and amino acids. This is the first study to indicate that fluoxetine may exert antidepressant action by regulating the astrocyte’s lipid and amino acid metabolism. These findings should aid our understanding of the biological mechanisms underlying fluoxetine therapy.     

Integrated Metabolomics and Morpho-Biochemical Analyses Reveal a Better Performance of Azospirillum brasilense over Plant-Derived Biostimulants in Counteracting Salt Stress in Tomato

Increased soil salinity is one of the main concerns in agriculture and food production, and it negatively affects plant growth and crop productivity. In order to mitigate the adverse effects of salinity stress, plant biostimulants (PBs) have been indicated as a promising approach. Indeed, these products have a beneficial effect on plants by acting on primary and secondary metabolism and by inducing the accumulation of protective molecules against oxidative stress. In this context, the present work is aimed at comparatively investigating the effects of microbial (i.e., Azospirillum brasilense) and plant-derived biostimulants in alleviating salt stress in tomato plants by adopting a multidisciplinary approach. To do so, the morphological and biochemical effects were assessed by analyzing the biomass accumulation and root characteristics, the activity of antioxidant enzymes and osmotic stress protection. Furthermore, modifications in the metabolomic profiles of both leaves and root exudates were also investigated by ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS). According to the results, biomass accumulation decreased under high salinity. However, the treatment with A. brasilense considerably improved root architecture and increased root biomass by 156% and 118% in non-saline and saline conditions, respectively. The antioxidant enzymes and proline production were enhanced in salinity stress at different levels according to the biostimulant applied. Moreover, the metabolomic analyses pointed out a wide set of processes being affected by salinity and biostimulant interactions. Crucial compounds belonging to secondary metabolism (phenylpropanoids, alkaloids and other N-containing metabolites, and membrane lipids) and phytohormones (brassinosteroids, cytokinins and methylsalicylate) showed the most pronounced modulation. Overall, our results suggest a better performance of A. brasilense in alleviating high salinity than the vegetal-derived protein hydrolysates herein evaluated.     

Untargeted Lipidomics Analysis of the Cyanobacterium Synechocystis sp. PCC 6803: Lipid Composition Variation in Response to Alternative Cultivation Setups and to Gene Deletion

Cyanobacteria play an important role in several ecological environments, and they are widely accepted to be the ancestors of chloroplasts in modern plants and green algae. Cyanobacteria have become attractive models for metabolic engineering, with the goal of exploring them as microbial cell factories. However, the study of cyanobacterial lipids’ composition and variation, and the assessment of the lipids’ functional and structural roles have been largely overlooked. Here, we aimed at expanding the cyanobacterial lipidomic analytical pipeline by using an untargeted lipidomics approach. Thus, the lipid composition variation of the model cyanobacterium Synechocystis sp. PCC 6803 was investigated in response to both alternative cultivation setups and gene deletion. This approach allowed for detecting differences in total lipid content, alterations in fatty-acid unsaturation level, and adjustments of specific lipid species among the identified lipid classes. The employed method also revealed that the cultivation setup tested in this work induced a deeper alteration of the cyanobacterial cell lipidome than the deletion of a gene that results in a dramatic increase in the release of lipid-rich outer membrane vesicles. This study further highlights how growth conditions must be carefully selected when cyanobacteria are to be engineered and/or scaled-up for lipid or fatty acids production.     

白蛋白制剂中辛酸含量的测定

在检品中加入定量庚酸作内标,经酸处理,氯仿抽提,溶剂挥发浓缩后,用气相层析法测定。在制作标准曲线时,以不同辛酸量和各自的辛酸与内标庚酸的峰面积比值回归。将检品测得的峰面积比值代入回归方程,即可求得辛酸含量。本法的回收率为96.88±1.19％;对17批制品分别重复测定4次的差异系数在1.21～4.62％之间,平均为2.72％,本法操作相对简便,可作为白蛋白辛酸含量的质控方法。     

壬二酸及其衍生物在护肤美容中的应用

主要介绍壬二酸的药理学作用以及壬二酸及其衍生物在护肤和美容方面的应用。     

Human iPSC-Derived Astrocytes: A Powerful Tool to Study Primary Astrocyte Dysfunction in the Pathogenesis of Rare Leukodystrophies

Astrocytes are very versatile cells, endowed with multitasking capacities to ensure brain homeostasis maintenance from brain development to adult life. It has become increasingly evident that astrocytes play a central role in many central nervous system pathologies, not only as regulators of defensive responses against brain insults but also as primary culprits of the disease onset and progression. This is particularly evident in some rare leukodystrophies (LDs) where white matter/myelin deterioration is due to primary astrocyte dysfunctions. Understanding the molecular defects causing these LDs may help clarify astrocyte contribution to myelin formation/maintenance and favor the identification of possible therapeutic targets for LDs and other CNS demyelinating diseases. To date, the pathogenic mechanisms of these LDs are poorly known due to the rarity of the pathological tissue and the failure of the animal models to fully recapitulate the human diseases. Thus, the development of human induced pluripotent stem cells (hiPSC) from patient fibroblasts and their differentiation into astrocytes is a promising approach to overcome these issues. In this review, we discuss the primary role of astrocytes in LD pathogenesis, the experimental models currently available and the advantages, future evolutions, perspectives, and limitations of hiPSC to study pathologies implying astrocyte dysfunctions.     

高效液相色谱法测定尿中马尿酸、甲基马尿酸三种同分异构体

采用高效液相色谱法测定了马尿酸及甲基马尿酸三种同分异构体。尿样中马尿酸及甲基马尿酸在酸性条件下经乙酸乙酯提取蒸干,以水溶解,以甲醇乙酸铵作流动相经C18柱分离、波长230nm高效液相法测定。结果表明,该方法能有效分离尿样中的马尿酸、甲基马尿酸同分异构体,准确灵敏,回收率高,可应用于检测尿样中的马尿酸、甲基马尿酸同分异构体。     

高铬铁素体不锈钢在硫酸和湿法磷酸生产中的应用

在当今金属镍价格不断上涨的情况下,开发和使用不合贵重金属镍而力学性能和耐腐蚀性能都十分优良的高铬铁素体不锈钢具有很重要的经济意义：调整高铬铁素体不锈钢中的碳含量,可改变其物化性能,介绍了超低碳、低碳和高碳高铬铁素体不锈钢的特点,以及它们在高温浓硫酸和湿法磷酸生产设备中的应用情况。     

反相液相色谱法测定废水中的马来酸和富马酸

建立了反相高效液相色谱同时分离分析废水中的马来酸和富马酸的方法。样品用流动相溶解稀释,以Krornasil-C18为色谱柱,流动相为甲醇和水(pH=2.53)(体积比为3∶97),检测波长为210 nm,外标法定量。结果表明,马来酸和富马酸分别在2.698～26.980 g/L、2.328～20.952g/L范围内线性关系良好(r0.9995)。该方法具有操作简便、快速、重现性好等特点,并应用于对马来酸废水处理工艺中进行分析。