ME Activity Research Articles

24-Epibrassinolide promoted growth and organic compounds accumulation in Dunaliella parva by enhancing photosynthesis

As a commonly used type of the sixth class of phytohormones brassinosteroids (BRs), 24-epibrassinolide (EBL) plays the important roles in plant growth and development. Dunaliella parva (D. parva) is an important lipid-producing microalga, and its growth and accumulation of organic compounds need to be further improved for higher application value. However, the effects of EBL on D. parva are still unclear now. In this study, D. parva was treated with different concentrations of 24-epibrassinolide (EBL) to evaluate its influence. Cell density of 0.5 mg/L EBL treated group was 1.28-fold of control at 18 d. The contents of chlorophyll, carotenoid, carbohydrate, starch, protein of 0.5 mg/L EBL treated group were 1.31-, 1.18-, 1.49-, 1.35-, and 1.54-fold of control. The highest mRNA levels of rbcS, rbcL, RuPE, PRK, TPI, FBPA, FBPase, SBPase, DpME, CA in EBL treated group were 1.94-, 2.43-, 2.14-, 1.76-, 1.97-, 2.21-, 1.48-, 1.96-, 2.06-, and 1.89-fold of control. The highest enzymatic activities of ME, CA and RuBisCO in EBL-treated group were 1.27-, 1.23-, and 1.37-fold of control. Lipid content of 0.4 mg/L EBL treated group was 1.44-fold of control. This study demonstrated the great potential of EBL to obtain higher biomass and organic compounds accumulation. Our study indicates that EBL treatment is valuable for the subsequent commercial production of biofuel and other high-value metabolites using microalgal biomass as raw material.

Возможности метода биохемилюминисценции с модельной средой из сыворотки крови в оценке антиоксидантной активности растительного сырья

Antioxidant activity (AOA) is an important indicator of the evaluation of plant raw materials (RM), which are widely used in medicine to obtain various medicines. The use of RM at the present stage of the pharmaceutical industry development allows avoiding large-scale production of synthetic medicines, accompanied by a negative impact on the environment. For an objective assessment of AOA, it is necessary to apply methods that allow determining not only the content of the active substance, but also generally characterizing the functional activity of RM. The article presents data on the AOA of aqueous extracts from the leaves and fruits of Hippophae rhamnoides L., Aronia melanocarpa L. The determination of antioxidant activity was performed by biochemiluminiscence (BСHL) using serum from white mongrel rats as a model environment (MЕ). The evaluation criteria were the maximum intensity (Imax) and the light sum of the glow (S). The results obtained were compared with the data of the analysis of BCHL without ME, as well as with the data of alternative methods for quantifying the antioxidant potential of RM (coulometric titration, direct titration, spectrophotometry). According to the criteria for assessing the intensity of free radical oxidation (Imax) using the BCHL method without ME, it was found that aqueous extracts from the leaves and fruits of A. melanocarpa, as well as H. rhamnoides leaves, have a high antioxidant potential (343, 274 and 268 mV, respectively), and from H. rhamnoides fruits – more short. BCHL results showed that the amount of radicals in blood serum decreased upon contact with extracts from vegetable raw materials. Among the studied samples, extracts from the fruits of A. melanocarpa were characterized by the highest AOA (S=2006±137 mV·s). At the same time, according to alternative methods, they occupy an intermediate position in terms of the quantitative content of biologically active substances (BAS) with antioxidant properties. Based on the weak correlation between the data of the BСHL method and alternative methods for determining AOA, it is concluded that it is necessary to take into account the possibility of an indirect relationship between the content of BAS in RM and the effect manifested in conditions as close as possible to biological systems. The measurement of AOA by the BСHL method is actually an assessment of the function, as well as the effectiveness of BAS, and complements quantitative methods for assessing the antioxidant activity of ME.

“Sexual activity for me is something else. It's the same as always: Sex aside and our love for each other.” Changes in sexual activity in dementia from the view of spouse-carers'

The study aimed to explore the impact of Alzheimer's disease (AD) on spouse-carer's lives and the ways it affects their marital relationship and sexual activity. Data were obtained from qualitative interviews conducted with 11 spouse-carers of people with AD. Using interpretative phenomenological analysis (IPA), three themes emerged: psychological and emotional impact, social impact, and sexual impact. Some spouse-carers reported stress, poor emotional well-being, frustration, doubts about how to deal with the situation, sadness, loneliness, perception of losing connection with the partner, and feelings of companionship disappearing. Meanwhile, other spouse-carers reported closer relations and greater affection for their care-recipients after the diagnosis. Changes in sexual activity were attributed to aging and/or the effects of the illness. Gender influenced the perception of changes in the marital relationship but not in sexual activity. Participants reported conflicting perspectives towards the importance of sexual activity in the marital relationship and the replacement of sexual intercourse with other modes of expressing affection. We believe that understanding the specificities of marital relationships of couples in whom one spouse was diagnosed with AD would be helpful for developing coping strategies for persons living with dementia and their spouses.

Phytochemical Profiling and Antiviral Activity of Green Sustainable Nanoparticles Derived from Maesa indica (Roxb.) Sweet against Human Coronavirus 229E.

Plant secondary metabolites are key components for new, safe and effective drugs. Ethanolic extract of Maesa indica Roxb. Sweet (ME) aerial parts were used for biosynthesis of sustainable green zinc oxide nanoparticles (ZnO NPs) with an average particle size 6.80 ± 1.47 nm and zeta potential -19.7 mV. Both transmission electron microscopy and X-ray diffraction assay confirmed the hexagonal shape of ZnO NPs. Phenolic ingredients in ME were identified using LC-ESI-MS/MS-MRM revealing the identification of chlorogenic acid, gallic acid, caffeic acid, rutin, coumaric acid, vanillin, naringenin, quercetin, ellagic acid, 3.4-dihydroxybenzoic acid, methyl gallate, kaempferol, ferulic acid, syringic acid, and luteolin. The major compound was chlorogenic acid at concentration of 1803.84 μg/g. The antiviral activity of ME, ZnO NPs, and combination of ME with ZnO NPs against coronavirus 229E were investigated. ZnO NPs had superior antiviral effect against coronavirus 229E than ME while their combination showed the highest anti-coronavirus 229E effect, with 50% inhibition concentration (IC50) of 5.23 ± 0.18 µg/mL and 50% cytotoxic concentration (CC50) of 138.49 ± 0.26 µg/mL while the selectivity index (SI) was 26.47. The current study highlighted the possible novel anti-coronavirus 229E activity of green ZnO NPs synthesized from Maesa indica. More studies are needed to further investigate this antiviral activity to be utilized in future biomedical and environmental applications.

Efficient lipid synthesis of Chlorella pyrenoidosa promoted under heavy metals from electric arc furnace slag

Electric furnace slag was highly productive and rich in elements, which can be used as a nutrient source for microalgae growth. The regulation of growth and lipid synthesis of Chlorella pyrenoidosa (C. pyrenoidosa) in electric arc furnace slag leaching solution with or without citric acid was investigated to develop efficient lipid production method with low cost. High lipid content of 45.89 wt% from C. pyrenoidosa with adding electric arc furnace slag leaching solution ≤40% into BG11 was obtained due to C. pyrenoidosa increasing lipid accumulation to resist oxidative stress caused by heavy metals in electric arc furnace slag (Ca of 5.13 mg/L, Fe of 0.05 mg/L, Mn of 0.12 mg/L and Cr of 0.01 mg/L). Exogenous citric acid can improve the ability of C. pyrenoidosa to resist heavy metal toxicity with high biomass content (0.44 g/L) achieved. The cooperation of multiple metal ions in electric arc furnace slag shortened the biomass accumulation stage and prolonged and speeded up the lipid synthesis stage of C. pyrenoidosa by modulating PEPC, ACC and ME activities. This study provided guidance for the industrialization of low-cost lipid-rich microalgae and metallurgical solid waste treatment.

Astaxanthin Extract from Haematococcus pluvialis and Its Fractions of Astaxanthin Mono- and Diesters Obtained by CCC Show Differential Antioxidant and Cytoprotective Effects on Naïve-Mouse Spleen Cells.

Carotenoids are the most abundant lipid-soluble phytochemicals and are used as dietary supplements to protect against diseases caused by oxidative stress. Astaxanthin, a xanthophyll carotenoid, is a very potent antioxidant with numerous beneficial effects on cellular functions and signaling pathways. In this study, using spleen cells from healthy Balb/c mice, we report the bio-functional effects of an astaxanthin-rich extract (EXT) prepared from the microalga Haematococcus pluvialis and its astaxanthin monoesters-rich fraction (ME) and astaxanthin diesters-rich fraction (DE) obtained by fractionation of EXT using countercurrent chromatography (CCC). After incubation under standard culture conditions (humidity, 37 °C, 5% CO2, atmospheric oxygen), the viability of untreated splenocytes, as determined by the trypan blue exclusion assay, the MTT assay, and the neutral red assay, decreases to approximately 75% after 24 h compared with naïve splenocytes. This effect correlated with the decrease in mitochondrial membrane potential and the transition of ~59% of cells to the early stage of apoptosis, as well as with the decreased ROS production, indicating that hyperoxia in cell-culture deteriorates cell functions. They are restored or stimulated by co-cultivation with EXT, ME, and DE up to 10 µg/mL in the order EXT > DE > ME, suggesting that esterification increases bioavailability to cells in vitro. ROS and H2O2 concentrations reflect mRNA transcriptional activity of Nrf2, superoxide dismutase 1 (SOD1), catalase, and glutathione peroxidase 1, as well as SOD-mediated ROS conversion, whereas they inversely correlate with iNOS-mediated NO production. The highest-tested concentration of EXT, ME, and DE (40 µg/mL) is detrimental to cells, probably because of the overwhelming scavenging activity of astaxanthin and its esters for the reactive oxygen/nitrogen species required for cellular functions and signal transduction at low physiological concentrations. In this study, we demonstrate that differential activities of ME and DE contribute to the final antioxidant and cytoprotective effects of astaxanthin extract, which is beneficial in preventing a wide range of ROS-induced adverse effects, with DE being more effective. In addition, the selection of physioxia-like conditions for pharmacological research is highlighted.

The effect of phytoprotectors on the functioning of liver NAD⁺- and NADP⁺-maliс enzymes in rats with alloxan diabetes.

The development of experimental alloxan diabetes in rats was accompanied by the increase the activity of liver NAD⁺- and NADP⁺-dependent malic enzymes (ME; NAD⁺-ME, EC 1.1.1.39 and NADP⁺-ME, 1.1.1.40) associated with an increase in the rate of transcription of genes encoding these enzymes. Oral administration of aqueous extracts of Jerusalem artichoke and olive to diabetic rats caused a noticeable decrease in blood glucose, a decrease in the rate of transcription of the studied genes; and a decrease in ME activity towards normal values. Thus, extracts of Jerusalem artichoke and olive can be used as additives to the standard therapy of diabetes mellitus.

Reduced Meal Frequency Decreases Fat Deposition and Improves Feed Efficiency of Growing-Finishing Pigs.

Simple SummaryIn this research, we studied the effects of feeding frequency (three meals per day vs. free access to feed) on growth performance, nutrient digestibility, carcass quality, and lipid metabolism in growing–finishing pigs. The results showed that reducing feeding frequency can effectively improve the feed conversion ratio. The three meals per day group had a different growth performance in terms of reduced fat deposition and changed carcass composition. This study provides a new scheme for the feeding and management of growing–finishing pigs.An experiment was conducted to examine the effect of meal frequency on growth performance, nutrient digestibility, carcass quality, and lipid metabolism in growing–finishing pigs. Sixty-four Duroc × Landrace × Yorkshire barrows and gilts (26.40 ± 2.10 kg initial body weight) were used in a 112-d experiment in a randomized complete blocked design. The two treatments were the free-access feed group (FA) and the three meals per day group (M3), respectively. The result showed that the average daily feed intake (ADFI) and F: G of the FA group were significantly higher than that in the M3 group during the whole experiment (p < 0.05). Reducing meal frequency also decreased the concentration of triglycerides and urea nitrogen but increased the concentration of insulin and free fatty acids in the blood (p < 0.05). Reducing meal frequency decreased compositions of backfat, belly, and fatty pieces but increased compositions of ham, longissimus muscle, and lean pieces in the carcass (p < 0.05). Greater enzyme activities of ME and FAS and higher mRNA expression of FAS and PPARγ were found in the LM of FA pigs compared with M3 pigs (p < 0.05). In summary, a lower meal frequency improves feed efficiency by regulating lipid metabolism and reducing fat deposition.

Superoxide Anion Release by Human Blood Phagocytes Can Increase the Microbicidal Activity Induced by a New Microemulsioned System Containing Cotton Oil

The study aimed to develop and characterize a microemulsified system based on cotton oil and verify its effect on superoxide release anion and microbicidal activity by human peripheral blood cells. Microemulsions were formulated using distilled water, degummed cotton oil, Span 80 (SP), Tween 80 (TW), and 1-butanol (BT). The pseudo-ternary diagram delimited ME regions, and the points were pre-selected. The physical-chemical and rheological characterization of the microemulsions was carried out. The ME activity on the interactions between leukocytes and bacteria was analyzed by superoxide release, phagocytosis, and microbicidal activity. The developed formulation was classified as Oil/Water, with an average pH of 5.76, and the viscosity showed resistance to temperature changes. The rheological model of the Power Law classified the microemulsion as a non-Newtonian fluid with pseudoplastic characteristics. The cell viability of cotton oil microemulsion was greater than 90%. There was an increase in the superoxide release by MN phagocytes when treated with cotton oil microemulsion. The cotton oil microemulsion increased phagocytosis and microbicidal activity. The present study suggests that cotton oil is an alternative biomaterial for therapeutic applications, especially in treating infections.

The Effect of Symmetric and Asymmetric NHCs on the Structure and Catalytic Properties of Dialkylgallium Alkoxides in the Ring-Opening Polymerization of rac-Lactide—Linking the Structure, Activity, and Stereoselectivity

Manipulating the structure of alkylgallium alkoxides with asymmetric N-heterocyclic carbenes (NHCs) has led to the formation of essentially “on” and “off” states of catalytic gallium centers in the ring-opening polymerization (ROP) of rac-lactide (rac-LA), and has allowed to rationalize the effect of the NHC on the activity and stereoselectivity of Me2GaOR(NHC) complexes. The reactions of dimethylgallium alkoxides with asymmetric NHCs, due to differently substituted nitrogens, resulted in the formation of Me2GaOR(SI(Dipp-Mes)) (OR = OMe (1), OCH2CH2OMe (2), OCH(Me)CO2Me (3)) and Me2GaOR(SI(Me-Mes)) (OR = OMe (4), OCPh2Me (5)) complexes (SI(Dipp-Mes) = 1-(diisopropylphenyl)-3-(mesityl)-imidazolin-2-ylidene, SI(Me-Mes) = 1-(methyl)-3-(mesityl)-imidazolin-2-ylidene). The X-ray analysis of 1, 2, 4, and 5 revealed a strong effect of NHCs on their structure, manifested by the orientation of NHC with respect to Ga–CMe and Ga–O bonds, and OR alkoxide group. The latter, represented by a dihedral O–Ga–CNHC–N angle, have allowed to define the cavity required for the interaction of lactide with gallium and alkoxide groups, and subsequent insertion of lactide into the Ga–Oalkoxide bond. Despite small differences between the cavities of 1 and Me2GaOMe(SIMes) (SIMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene), the structures of NHCs were responsible for their isoselectivities, of Pm-max = 0.83 and Pm-max = 0.78, respectively, in the ROP of rac-LA at −20 °C. The much smaller cavity of 4 led to a minor activity and lower isoselectivity (Pm-max = 0.56 at −20 °C). Further decrease of the activity of Me(O,CNHC)GaOR (6), possessing both small cavity and, in contrast to 4, restrained rotation of Ga–CNHC bond of the chelate ligand, has supported the effect of NHC on the structure and activity of Me2GaOR(NHC) complexes. DFT calculations of the energy profile of the consecutive ring-opening of two lactide molecules into Ga–Oalkoxide bonds of 1, 4, and Me2GaOMe(SIMes) have confirmed the effect of NHC on their stereoselectivity.

Encapsulation of Carlina acaulis essential oil and carlina oxide to develop long-lasting mosquito larvicides: microemulsions versus nanoemulsions

Carlina acaulis root essential oil (EO) is one of the most potent mosquito larvicides (LC50 < 2 ppm). This EO is mainly composed of carlina oxide (> 90%). Poor water solubility and rapid degradation from UV light and oxygen in the environment limit the real-world use of this EO. Herein, we developed nanocarrier-based formulations, namely micro- and nanoemulsions (ME and NE, respectively) containing C. acaulis EO or carlina oxide (both at 0.5%) as active ingredients (a.i.). The larvicidal activity of ME and NE was evaluated against Culex quinquefasciatus. The highest larvicidal activity was achieved by the ME containing 0.5% of the EO (M1); its LC50(90) was 579.1 (791.3) µL L−1. Sublethal effects of this ME and its a.i. were assessed testing both at the LC16, LC30, LC50 and LC90 on mosquito larvae exposed to each product for 1–7 h, and then monitoring mortality for 18 days. At variance with the EO, ME application, even at LC16, led to 100% mortality at 18 days. The EO and its encapsulated form were scarcely toxic to human keratinocytes (HaCaT) and human fibroblast (NHF A12) cell lines. The acute toxicity of C. acaulis EO and its ME (M1) was also evaluated in Wistar rats through oral administration; EO LD50 was 1098 mg kg−1 bw, whereas its ME, even at 5000 mg kg−1 bw (considered the upper testing limit to establish safety to mammals), was not toxic. This study highlights the outstanding efficacy of C. acaulis EO ME for developing long-lasting and safe larvicides against Cx. quinquefasciatus.

Composing Capital: Classical Music in the Neoliberal Era. By Marianna Ritchey

“If you can’t say something good about someone,” the socialite and noted wit Alice Roosevelt Longworth once quipped, “sit right here by me.”1 Marianna Ritchey, whose excellent new book, Composing Capital: Classical Music in the Neoliberal Era, has nothing good to say about “the degree to which capitalist ideology has infiltrated our assessments of musical value” (3), can consider this review an invitation to sit right here by me. Like Ritchey, I suffer from an allergy to the jargon of individualism, entrepreneurialism, innovation, outreach, and bureaucratic “diversity management” (38) with which the culture and discourse of contemporary classical music is saturated. Reading Ritchey’s intransigently censorious monograph proved to be at least as much a therapeutic as an educational activity for me; to be reminded that one is not alone in one’s suffering is to be relieved of some of it. No doubt other music scholars who are made morose by “how neoliberal common sense has shaped the academic, journalistic, and pedagogical discourses concerning classical music in contemporary practice” (5) will find similar salubriousness in the pages of Composing Capital. Although I have a handful of music-theoretical and political objections to register here, I think that Ritchey wrote the right book at the right time in the right way, and also that her project provides plenty of intellectual fodder for music theorists.

Chemical composition, antibacterial activity and action mechanism of different extracts from hawthorn (Crataegus pinnatifida Bge.)

Present study was designed to compared the total flavonoids and polyphenols contents and antibacterial activity of hawthorn extracts with different polarities as well as the underlying antibacterial mechanisms. The results showed that among all hawthorn extracts, methanol and ethanol extracts (ME and EE) exhibited high levels of total flavonoids and polyphenols contents, followed by acetone, ethyl acetate, trichloromethane and petroleum ether extracts. ME exhibited the strongest antibacterial activity against tested bacteria, especially Staphylococcus aureus with a 1.25 μg/mL of the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). Further analysis revealed that the main phenolic compounds from ME were epicatechin (281.6 mg/100 g DW), procyanidin B2 (243.5 mg/100 g DW), chlorogenic acid (84.2 mg/100 g DW) and quercetin (78.4 mg/100 g DW). The action mechanism of ME against S. aureus could be ascribed to ME damaging cell wall and cell membrane integrity, inhibiting intracellular enzyme activity, increasing reactive oxygen species (ROS), also changing expression of associated genes and then inducing apoptosis of S. aureus. In addition, the antimicrobial activity of ME against S. aureus has also been demonstrated to be efficient in the food matrix (whole milk).

High-efficiency expression of a superior β-mannanase engineered by cooperative substitution method in Pichia pastoris and its application in preparation of prebiotic mannooligosaccharides

β-mannanase with high specific activity is a prerequisite for the industrial preparation of prebiotic mannooligosaccharides. Three mutants, namely MEI, MER, and MEIR, were constructed by cooperative substitution based on three predominant single-point site mutations (K291E, L211I, and Q112R, respectively). Heterologous expression was facilitated in Pichia pastoris and the recombinase was characterized completely. The specific activities of MER (7481.9 U mg−1) and MEIR (9003.1 U mg−1) increased by 1.07- and 1.29-fold from the initial activity of ME (6970.2U mg−1), respectively. MEIR was used for high-cell-density fermentation to further improve enzyme activity, and the expression levels achieved in the 10-L fermenter were significantly high (105,836 U mL−1). The prebiotic mannooligosaccharides (<2000 Da) were prepared by hydrolyzing konjac gum and locust bean gum with MEIR, with 100% and 76.40% hydrolysis rates, respectively. These characteristics make MEIR highly attractive for prebiotic development in food and related industries.

Dietary lipid level and source affect metabolic responses in hybrid catfish (Pseudoplatystoma reticulatum × Leiarius marmoratus)

This study was undertaken to evaluate the effect of dietary lipid source [linseed oil (LO, rich in 18:3 n−3); corn oil (CO, rich in 18:2 n−6); olive oil (OO, rich in 18:1n−9); and fish oil (FO, rich in LC-PUFA)] and level (9% L and 18% L) on growth, body composition and selected plasma biochemistry parameters in hybrid catfish (Pseudoplatystoma reticulatum × Leiarius marmoratus) juveniles. Moreover, liver histology (lipids, glycogen, cell vacuolization) and key metabolic enzyme activities were also evaluated. After 8 weeks of feeding, there were no differences in growth performance and whole-body composition between groups. Plasma lipoprotein, muscle and liver composition, and G6PD and ME activity were affected by lipid level and source. No differences were observed between groups in hepatic ALT activity; however, AST activity was lower in fish fed the 9% L diets. Overall, liver and muscle fatty acid composition reflected that of diet FA composition, with increased n3/n6 ratio, high HUFA and low MUFA in fish fed FO compared with the VO diets. Higher liver glycogen content was observed in fish fed the 18% L than the 9% L diets, except for fish fed FO diet. Considering the experimental diets used, these results indicate that hybrid catfish can efficiently utilize VO supplementation as an energy source, without affecting growth performance and fillet composition.

Optimization of Phenolic Compound Extraction from Chinese Moringa oleifera Leaves and Antioxidant Activities

Rich in phenolic compounds, Moringa oleifera leaf extract (ME) exhibits significant antioxidant activity both in vitro and in vivo. ME has already been widely used in fields of medicine, functional food, and cosmetics. Ultrasonic extraction (UE) method has been improved to be one of the most effective ways to extract phenols from M. oleifera leaves. The purpose of this study was to optimize ultrasonic extraction of phenols by response surface methodology (RSM). Four parameters were discussed, such as ethanol concentration, solvent-sample ratio, extraction temperature, and extraction time. Also, purification methods of the crude ME by organic solvent extraction and column chromatography were examined. Antioxidant activities of ME and each fraction were evaluated by DPPH, ABTS, and hydroxy radical-scavenging activities and reducing power. The phenol content of the purified ME reached up to 962.6 mg RE/g, extremely higher than the crude extract 107.22 ± 1.93 mg RE/g. The antioxidant activity of the purified ME was also significantly improved. Furthermore, phenols were identified by using the HPLC-MS method, and the results showed that there were 6 phenolic acids and derivatives and 7 flavonoids in ME. Quercetin-3-O-β-D-glucoside isolated from ME showed excellent DPPH and ABTS radical-scavenging abilities, which were comparable to VC.

Increasing lipid production using an NADP+-dependent malic enzyme from Rhodococcus jostii.

The occurrence of NADP+-dependent malic enzymes (NADP+-MEs) in several Rhodococcus strains was analysed. The NADP+-ME number in Rhodococcus genomes seemed to be a strain-dependent property. Total NADP+-ME activity increased by 1.8- and 2.6-fold in the oleaginous Rhodococcus jostii RHA1 and Rhodococcus opacus PD630 strains during cultivation under nitrogen-limiting conditions. Total NADP+-ME activity inhibition by sesamol resulted in a significant decrease of the cellular biomass and lipid production in oleaginous rhodococci. A non-redundant ME coded by the RHA1_RS44255 gene located in a megaplasmid (pRHL3) of R. jostii RHA1 was characterized and its heterologous expression in Escherichia coli resulted in a twofold increase in ME activity in an NADP+-dependent manner. The overexpression of RHA1_RS44255 in RHA1 and PD630 strains grown on glucose promoted an increase in total NADP+-ME activity and an up to 1.9-foldincrease in total fatty acid production without sacrificing cellular biomass. On the other hand, its expression in Rhodococcus fascians F7 grown on glycerol resulted in a 1.3-1.4-foldincrease in total fatty acid content. The results of this study confirmed the contribution of NADP+-MEs to TAG accumulation in oleaginous rhodococci and the utility of these enzymes as an alternative approach to increase bacterial oil production from different carbon sources.

SREBP-1 and LXRα pathways mediated Cu-induced hepatic lipid metabolism in zebrafish Danio rerio

The present study was performed to explore the underlying molecular mechanism of Cu-induced disorder of lipid metabolism in fish. To this end, adult zebrafish were exposed to three waterborne Cu concentrations (0 (control), 8 and 16 μg Cu/L, respectively) for 60 days. Hepatic Cu content and hepatosomatic index increased after waterborne Cu exposure. H&E and oil red O stainings showed extensive steatosis in the liver of Cu-exposed fish. Cu exposure up-regulated lipogenic enzymes activities of ME, ICDH, 6PGD, G6PD and FAS, but down-regulated CPTI activities. Transcriptomic analysis indicated that lipid metabolism related pathways were significantly enriched in both low-dose and high-dose Cu exposure group. Genes involved in lipogenic process from fatty acid biosynthesis, fatty acid elongation, fatty acid desaturation to glycerolipid biosynthesis were up-regulated by Cu. To elucidate the mechanism, LXRα inhibitor SR9243 and SREBP1 inhibitor fatostatin were used to verify the role of LXRα and SREBP1 in Cu-induced disorder of lipid metabolism. Both SR9243 and fatostatin significantly attenuated the Cu-induced increase of TG accumulation of hepatocytes. Meanwhile, SR9243 significantly attenuated the Cu-induced up-regulation of expression of lipogenic genes (acaca, fas, icdh, dgat1, moat2 and moat3), and fatostatin significantly attenuated the up-regulation of expression of acaca, fas, g6pd, dgat1 and moat2. Enzymes analysis showed both SR9243 and fatostatin blocked the Cu-induced increase of lipogenic enzymes activities. Taken together, our findings highlight the importance of LXRα and SREBP1 in Cu-induced hepatic lipid deposition, which proposed a novel mechanism for elucidating metal element exposure inducing the disorder of lipid metabolism in aquatic vertebrates.

Evaluation the effect of Myrtus communis L. extract on several underlying mechanisms involved in wound healing: An in vitro study

ObjectiveMyrtus communis L. (Myrtle) has been widely used in traditional remedies for curing several medical conditions including wounds. However, studies addressing its detailed molecular mechanisms especially those involved in the angiogenic process are still limited. Hence, the current study was aimed to investigate the effect of ethanol extract of myrtle leaves ME on some molecular mechanisms involved in the wound healing process. MethodsFirstly, the effect of ME on the viability of HUVECs, 3T3 fibroblast cell line and J774A.1 macrophage was evaluated using MTT assay. Moreover, the effect of ME on the migration of HUVECs was evaluated by the scratch assay. The protein expression of HIF-1α and VEGF in HUVECs was analyzed using western blotting. To evaluate the anti-inflammatory effect of ME on lipopolysaccharide (LPS)-stimulated J774A.1 macrophage, the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at mRNA level was assessed using qRT-PCR. Furthermore, in vitro antimicrobial and antioxidant activities of ME were accomplished. ResultsAt concentration lower than 6 μg/mL, ME showed no significant toxic effect on all three cell lines. ME significantly reduced the expression of iNOS and COX-2 at mRNA level in LPS-stimulated J774A.1 macrophage as well as increased expression of HIF-1α and VEGF at the protein level in HUVECs. The migratory potential of HUVECs was enhanced by ME. The ME showed potent antioxidant activity at concentrations ≥15 μg/mL. Staphylococcus aureus and Bacillus subtilis were more sensitive to ME than other spices. ConclusionThe present study may provide more detailed information about the underlying mechanisms involved in wound healing effect of ME.

Abstract 777: Malic enzyme 3 as a collateral lethality target in pancreatic cancer

Abstract Cancer genomes possess many deletion events targeting tumor suppressor genes (TSG) and neighboring genes in these loci. These deletion patterns prompted us to consider a systematic approach, termed “collateral lethality”, designed to identify cancer-specific vulnerabilities resulting from the deletion of neighboring genes. These bystander genes do not appear to be involved in cancer pathogenesis, yet encode cell-essential functions and are members of multi-gene families that are functionally redundant and co-expressed. Homozygous deletion of SMAD4 is a frequent event in pancreas cancer and other cancer types, totaling &amp;gt;30,000 cases in US annually. SMAD4 deletion often results in co-deletion of the neighboring mitochondrial malic enzyme 2 (ME2) gene. In mammalian cells, two genes (ME2 and ME3) encode redundant cell-essential mitochondrial ME activity. Together, ME2 and ME3 function to generate pyruvate to fuel the TCA cycle, and NADPH to maintain ROS homeostasis. These observations prompted us to hypothesize that the genetic or pharmacological extinction of ME3 activity in a ME2 null cell would specifically compromise cancer cells yet be tolerated in normal host cells possessing ME2 activity. Inducible shRNA strategies were employed to genetically deplete ME3 in ME2-null versus ME2-intact cells followed by apoptosis measurements, integrated metabolomics, and molecular investigations. In collaboration with IONIS Pharmaceuticals, we tested and validated anti-sense oligonucleotide (ASO) to target ME3. Genetic depletion of ME3 in ME2 null, but not ME2 intact, cells resulted in apoptosis and blocked tumorigenic potential. Mechanistically, integrated metabolomic and molecular investigation of mitochondrial ME-deficient cells revealed diminished NADPH production and consequent high ROS, which activates AMP activated protein kinase (AMPK) and which in turn directly suppresses sterol regulatory element-binding protein 1 (SREBP1)-directed transcription of its direct targets including the BCAT2 (Branched chain amino acid transaminase 2) gene. We also determined that mitochondrial MEs regulate the utilization of branched chain amino acid (BCAA) via BCAT2, a transaminase required for BCAA catabolism. Notably, enforced expression of BCAT2 can restore tumorigenic potential of ME2/3 deficiency, and free nucleotides can restore proliferation in cell culture. Specific targeting of ME3 using ASOs could dramatically reduce tumor burden in a subQ tumor model of pancreatic cancer. Thus, a key mechanism driving cancer cell lethality involves BCAAs as crucial metabolites under the critical regulation of the mitochondrial MEs. These studies reveal a collateral lethal vulnerability in pancreas and other cancers that can be targeted pharmacologically in genotype-defined patient populations. We propose that highly specific ME3 inhibitors could provide an effective therapy across a substantial number of cancer patients. Citation Format: Prasenjit Dey, Joelle Baddour, Youngsoo Kim, Robert Macloed, Florian Muller, Chia Chin Wu, Huamin Wang, Andrea Viale, Haoqiang Ying, Giulio Draetta, Anirban Maitra, Alan Wang, Deepak Nagrath, Ronald DePinho. Malic enzyme 3 as a collateral lethality target in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 777.