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关键词： Berberis kansuensis   metabolomics   biochemistry assay   NMR spectroscopy   diabetes   pathway analysis   biological activity  

摘要： The dried stem bark ofBerberis ***. (Berberidaceae) was widely used to treat diabetes in traditional Tibetan medicine system. However, its anti-diabetic mechanisms have not been elucidated. In this study,H-1-NMR-based metabolomics combined with biochemistry assay was applied to investigate the anti-diabetic activities as well as underlying mechanisms ofB. kansuensisextract on type 2 diabetic rats. The results showed that after 30 days treatment withB. kansuensisextract, the levels of FBG, GSP, INS, TNF-alpha, IL-1 beta and IL-6 were significantly decreased inB. kansuensisgroup compared with the model group. Besides, a total of 28 metabolites were identified in rat serum by(1)H-NMR-based metabolomics method, 16 of which were significantly different in the normal group compared with the model group, and eight of them were significantly reversed afterB. kansuensisintervention. Further analysis of metabolic pathways indicated that therapeutic effect ofB. kansuensismight be predominantly related to their ability to improve glycolysis and gluconeogenesis, citric acid cycle, lipid metabolism, amino acid metabolism and choline metabolism. The results of both metabolomics and biochemical analysis indicated thatB. kansuensisextract has a potential anti-diabetic effect on type 2 diabetic rats. Its therapeutic effect may be based on the ability of anti-inflammation, alleviating insulin resistance and restoring several disturbed metabolic pathways.

关键词： Flavoproteins   D-amino acids   Structure-function relationships   Protein stability   Cofactor binding  

摘要： D-amino acids research field has recently gained an increased interest since these atypical molecules have been discovered to play a plethora of different roles. In the mammalian central nervous system, D-aspartate (D-Asp) is critically involved in the regulation of glutamatergic neurotransmission by acting as an agonist of NMDA receptor. Accordingly, alterations in its metabolism have been related to different pathologies. D-Asp shows a peculiar temporal pattern of emergence during ontogenesis and soon after birth its brain levels are strictly regulated by the catabolic enzyme D-aspartate oxidase (DASPO), a FAD-dependent oxidase. Rodents have been widely used as in vivo models for deciphering molecular mechanisms and for testing novel therapeutic targets and drugs, but human targets can significantly differ. Based on these considerations, here we investigated the structural and functional properties of the mouse DASPO, in particular kinetic properties, ligand and flavin binding, oligomerization state and protein stability. We compared the obtained findings with those of the human enzyme (80% sequence identity) highlighting a different oligomeric state and a lower activity for the mouse DASPO, which apoprotein species exists in solution in two forms differing in FAD affinity. The features that distinguish mouse and human DASPO suggest that this flavoenzyme might control in a distinct way the brain D-Asp levels in different organisms.

摘要： Plants are constantly exposed to environmental fluctuations, that may occur in a single day or over longer periods. In many cases, abiotic stresses are transient and recurrent, impacting how plants respond in subsequent adverse conditions. Adaptation mechanisms may occur at the physiological, biochemical and molecular level, modifying transcriptional response, regulatory proteins, epigenetic marks or metabolites. Here, we aimed to uncover the different strategies that rice uses to respond to recurrent stress. We tested varieties with contrasting behavior towards salinity (tolerance or sensitivity) and imposed salt stress (150 mM NaCl) during 48 h at vegetative and/or reproductive stages. After 48 h of stress in reproductive stage, leaves and roots were harvested separately or otherwise the plants were submitted to a 24 h recovery, prior to sample harvesting. Plants submitted to a recurrent stress responded differently from those suffering a single stress event. In the case of the sensitive genotype, recurrent stress led to lower Na/K ratio in roots and lower hydrogen peroxide accumulation and lipid peroxidation in leaves, but maintenance of global DNA methylation levels. In the tolerant genotype, recurrent stress did neither affect the Na/K ratio nor the stomatal conductance, although the levels of superoxide anion and hydrogen peroxide accumulation were lower, as also observed for global levels of DNA methylation. Our work shows that a short pre-exposure to salt stress may improve rice tolerance to subsequent stress, trough biochemical, physiological and epigenetic processes, with more significant changes visible in the tolerant genotype.

关键词： Direct interspecies electron transfer (DIET)   Renewable energy   Methanogenesis   Efficient energy generation   Environment management   Natural iron mineral  

摘要： Methanogenesis for generation of renewable energy in geological ecosystems may be influenced by the in-situ iron oxides available. This study investigated the natural iron minerals (Magnetite, Hematite and Specularite) on rate of energy generation and biochemical pathways in the presence of methanol as a model substrate using microbial consortium enriched from oilfield production water. Enhanced (15%) and stimulated energy generation was achieved in the treatments amended with iron minerals compared to the controls without any amendment. The mineral amended treatments resulted in enrichment of bacterial community for Firmicutes, but no changes were observed in the archaea (Methanosarcina mazei). The dynamic changes of acetate and methane concentrations in different treatments during incubation indicated anaerobic fermentation of methanol to acetate occurred prior to syntrophic acetate oxidation coupling with hydrogenotrophic methanogenesis for methane bioenergy production, which was further verified thermodynamically. Iron minerals were suggested to serve as electron donors and conductive networks between syntrophic partners in the microbial community facilitating direct interspecies electron transfer for efficient energy generation. The investigation yielded prospects on efficient generation of renewable energy and environmental sustainability by natural iron minerals. It also provides insights about the key processes in the petroleum reservoirs, deep biosphere and engineered anaerobic systems. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： skin barrier   skin physiology   structure   axilla   hair removal   inflammatory cytokines   erythema  

摘要： Objective The impact of hair removal on the biophysical and biochemical characteristics of human axillary skin is not fully understood. This study investigated the effect of different hair-removal techniques on biophysical parameters and the concentrations of key inflammatory biomarkers in the axillae of female Thai subjects. Axillary hair was removed by shaving, plucking or waxing. Methods Following a 2-week washout phase without hair removal, subjects underwent visual assessment for erythema and skin dryness in one (randomized) axilla, then, hair was removed from the axilla by shaving, plucking or waxing according to each subject's established habit. Erythema and dryness were assessed again 30 min after hair removal, and buffer scrubs collected from depilated and non-depilated axillae and analysed for inflammatory cytokines;after a further 48 h, erythema, dryness and post-inflammatory hyperpigmentation (PIHP) were assessed in the depilated axilla. Biophysical assessments (skin hydration, barrier integrity, elasticity and roughness) were made in depilated and non-depilated axillae. Results All three hair-removal techniques induced an increase in axillary erythema and skin dryness. Shaving was associated with significantly less erythema (P < 0.01), but significantly greater skin dryness (P < 0.05) versus the other techniques 30 min after hair removal. There were no between-technique differences in PIHP or biophysical parameters. Interleukins IL-1 alpha and IL-1RA concentrations increased, and IL-8 concentration decreased following hair removal by each technique. Conclusion This is the first study to identify the principal cytokines associated with the inflammatory process triggered by axillary hair removal. A single hair-removal treatment did not appear to induce PIHP or further biophysical changes to the skin.

关键词： fluoride   cerebellum   oxidative stress   proteomic  

摘要： Although the literature does not provide evidence of health risks from exposure to fluoride (F) in therapeutic doses, questions remain about the effects of long-term and high-dose use on the function of the central nervous system. The objective of this study was to investigate the effect of long-term exposure to F at levels similar to those found in areas of artificial water fluoridation and in areas of endemic fluorosis on biochemical, proteomic, cell density, and functional parameters associated with the cerebellum. For this, mice were exposed to water containing 10 mg F/L or 50 mg F/L (as sodium fluoride) for 60 days. After the exposure period, the animals were submitted to motor tests and the cerebellum was evaluated for fluoride levels, antioxidant capacity against peroxyl radicals (ACAP), lipid peroxidation (MDA), and nitrite levels (NO). The proteomic profile and morphological integrity were also evaluated. The results showed that the 10 mg F/L dose was able to decrease the ACAP levels, and the animals exposed to 50 mg F/L presented lower levels of ACAP and higher levels of MDA and NO. The cerebellar proteomic profile in both groups was modulated, highlighting proteins related to the antioxidant system, energy production, and cell death, however no neuronal density change in cerebellum was observed. Functionally, the horizontal exploratory activity of both exposed groups was impaired, while only the 50 mg F/L group showed significant changes in postural stability. No motor coordination and balance impairments were observed in both groups. Our results suggest that fluoride may impair the cerebellar oxidative biochemistry, which is associated with the proteomic modulation and, although no morphological impairment was observed, only the highest concentration of fluoride was able to impair some cerebellar motor functions.

关键词： biglycan   cartilage   osteoarthritis   pericellular matrix   perlecan   spatial chondrocyte organization  

摘要： During osteoarthritis, chondrocytes change their spatial arrangement from single to double strings, then to small and big clusters. This change in pattern has recently been established as an image-based biomarker for osteoarthritis. The pericellular matrix (PCM) appears to degrade together alongside cellular reorganization. The aim of this study was to characterize this PCM-degradation based on different cellular patterns. We additionally wanted to identify the earliest time point of PCM-breakdown in this physiopathological model. To this end, cartilage samples were selected according to their predominant cellular pattern. Qualitative analysis of PCM degradation was performed immunohistochemically by analysing five main PCM components: collagen type VI, perlecan, collagen type III, biglycan, and fibrillin-1 (n = 6 patients). Their protein content was quantified by enzyme-linked immunosorbent assay (127 patients). Accompanying spatial cellular rearrangement, the PCM is progressively destroyed, with a pericellular signal loss in fluorescence microscopy for collagen type VI, perlecan, and biglycan. This loss in protein signal is accompanied by a reduction in total protein content from single strings to big clusters (P < .001 for collagen type VI, P = .003 for perlecan, and P < .001 for biglycan). As a result of an increase in the number of cells from single strings to big clusters, the amount of protein available per cell also decreases for collagen type III and fibrillin-1, where total protein levels remain constant. Biochemical changes of the PCM and cellular rearrangement are thus highly interconnected hallmarks of osteoarthritis. Interestingly, the earliest point in time for a relevant PCM impairment appears to be at the transition to small clusters.

关键词： Abiotic stress   Taxanes   Paclitaxel   Total phenol   Antioxidant  

摘要： The metabolic stimulation induced by abiotic stress is an efficient strategy for the production of secondary metabolites in sterile and controlled plant cell, tissue, and organ cultures. Paclitaxel (taxol), one of the most widely used therapeutic compounds for the treatment of various cancers, is mainly produced through cell culture of the European yew (Taxus baccataL.). In this work, aT. baccatacallus culture was subjected to drought stress inducedin vitroby mannitol and sorbitol (1, 2, 3, and 4%) and sucrose (6 and 8%) to evaluate its impact on physiological and biochemical traits as well as paclitaxel and 10-deacetyl baccatin III (10-DBA) production. It was observed that drought stress caused a significant increase (P< 0.05) in dry weight, proline, soluble sugars, hydrogen peroxide, lipid peroxidation, total phenolics, flavonoids, and flavonols, and a decrease in relative water content, fresh weight, relative growth rate, and cell viability. Constitutive activities of superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase, and glutathione reductase were enhanced by the induced stress. The content of paclitaxel and 10-DBA was higher in stressed cultures than in the control. It can be concluded thatT. baccatacells have a protection mechanism against oxidative damage involving induced activities of enzymatic and non-enzymatic antioxidants. The induction of moderate drought stress could therefore be an effective strategy for increasing taxanes production inT. baccatacallus cultures.

关键词： Allophycocyanin   Atacama desert   Chroococcidiopsis sp   Endolithic   Phycobiliproteins  

摘要： Molecular and microscopic studies were performed to identify Chroococcidiopsis sp., an endolithic cyanobacterium, isolated from gypsum rocks of Atacama Desert (Chile). It was adapted to grow in mineral liquid medium, with 9 mM nitrate, bubbled with CO2-enriched air (2.5 % v/v), and continuously illuminated with a white light of 70 mu mol photons m(-2) s(-1). The obtained biomass (productivity of 0.21 g L-1 d(-1)) had a C/N ratio of 6.67, and it contained carbohydrates (45.40 % of dry weight), proteins (36.72 %), lipids (5.60 %) nucleic acids (3.90 %) and ashes (8.28 %). The lipid fraction was particularly rich in palmitic (29.86 % of total fatty acids), linoleic (18.20 %), palmitoleic (12.75 %), linolenic (10.92 %), stearic (9.64 %) and capric acid (6.29 %). Chroococcidiopsis sp. accumulated phycobiliproteins in a light-dependent process and produced 204 mg g(-1), under incident light of 10 mu mol photons.m(-2).s(-1), with a relative abundance of 40.9 % for phycocyanin, 23.3 % for phycoerythrin, and 35.8 % for allophycocyanin. The biomass from this cyanobacterium can be a good source of these pigments, especially APC (maximum of 95 mg g dw(-1)), which are of interest for pharmacological, cosmetic, and food industries.