Optimizacija uslova mikrotalasne ekstrakcije fenolnih jedinjenja ploda divlje trešnje (Prunus Avium L.)

The aim of this study was to optimize the conditions of microwave extraction for determining the content of the total flavonoids of wild cherry fruits (Prunus avium L.). The conditions that are optimized are the percent of methanol, solvent to liquid ratio, the time and temperature of the extraction. Based on the experimental design and software package Design Expert 7.0.0, the optimal conditions for this type of extraction were determined: methanol percentage 70%, solid to liquid ratio 0.03 g / mL, extraction time 1.80 min and temperature 78 ° C. Using the DPPH method, the antioxidant activity of the extract obtained under optimal conditions was determined (IC50 = 5.14 mg mL-1).Cilj ovog rada bila je optimizacija uslova mikrotalasne ekstrakcije za određivanje sadržaja ukupnih flavonoida ploda divlje trešnje (Prunus avium L.). Uslovi koji su optimizovani su procenat metanola, odnos mase uzorka i rastvarača, vreme i temperatura ekstrakcije. Na osnovu eksperimentalnog dizajna i softverskog paketa Design Expert 7.0.0., određeni su optimalni uslovi ove vrste ekstrakcije i to su: procenat metanola 70%, odnos mase uzorka i rastvarača 0,03 g/mL, vreme ekstrakcije 1,80 min i temperatura 78 °C. Primenom DPPH metode ispitana je antioksidativna aktivnost ekstrakta dobijenog pod optimalnim uslovima (IC50 = 5,14 mg mL-1)

Highly potent antioxidant Olea europaea L. leaf extract affects carotid and renal haemodynamics in experimental hypertension

Haemodynamic alterations in carotid and renal arteries are associated with the severity of target organ damage in patients with hypertension. Dietary habits, such as the Mediterranean diet, regulate blood pressure and oxidative stress, thus reduce the mortality rate due to cardiovascular diseases. In this study, our aim was to evaluate the reducing activity, antioxidant capacity and metal chelating ability of standardized Olea europaea L. leaf extract (OLE), and to test its (5, 25, 50 mg/kg) acute in vivo effects, as well as oleuropein’s (OP, 10 mg/kg) on oxidative stress, carotid, renal and systemic haemodynamic parameters (blood pressure, heart rate, cardiac output, peripheral resistance) in spontaneously hypertensive rats (SHR). OLE has a higher antioxidative capacity than BHT, higher reducing ability than vitamin C, and 23 times lower capacity for metal ion chelation than EDTA. All three doses of OLE, and OP, improved oxidative stress in SHR. OLE5 improved carotid and renal haemodynamics, without significant effects on systemic haemodynamics. Two different mechanisms of antihypertensive responses to OLE were observed, OLE25 was most effective in reducing cardiovascular risks by improving systemic and regional (carotid and renal) haemodynamics, peripheral and regional vascular resistance. OLE50 causes the improvement of blood pressure and cardiac performances, but tends to retain elevated vascular resistance, therefore, reducing the inflow of blood into the brain and kidneys of the SHR. The OP did not alter systemic or regional haemodynamics, suggesting others constituents responsible for changes of cardiac function, as well as carotid and renal haemodynamics in response to OLE50

TET-mediated DNA hydroxymethylation is negatively influenced by the PARP-dependent PARylation

Background Poly(ADP-ribosyl)ation (PARylation), a posttranslational modification introduced by PARP-1 and PARP-2, has first been implicated in DNA demethylation due to its role in base excision repair. Recent evidence indicates a direct influence of PARP-dependent PARylation on TET enzymes which catalyse hydroxymethylation of DNA—the first step in DNA demethylation. However, the exact nature of influence that PARylation exerts on TET activity is still ambiguous. In our recent study, we have observed a negative influence of PARP-1 on local TET-mediated DNA demethylation of a single gene and in this study, we further explore PARP–TET interplay. Results Expanding on our previous work, we show that both TET1 and TET2 can be in vitro PARylated by PARP-1 and PARP-2 enzymes and that TET1 PARylation negatively affects the TET1 catalytic activity in vitro. Furthermore, we show that PARylation inhibits TET-mediated DNA demethylation at the global genome level in cellulo. Conclusions According to our findings, PARP inhibition can positively influence TET activity and therefore affect global levels of DNA methylation and hydroxymethylation. This gives a strong rationale for future examination of PARP inhibitors' potential use in the therapy of cancers characterised by loss of 5-hydroxymethylcytosine

Effects of losartan, tempol, and their combination on renal nitric oxide synthases in the animal model of chronic kidney disease

Down-regulation of nitric oxide synthase (NOS) and NO defi ciency in the kidneys have been implicated in the pathogenesis of chronic kidney disease (CKD). In this study we examined the effects of losartan, tempol, and combined treatment on three NOS isoforms expressions, kidney NO content and NOS correlation with renal function and structure in the early stage of adriamycin (ADR)-induced CKD in spontaneously hypertensive rats (SHR). Rats were divided into control group, and four other groups which were treated with ADR and received vehicle, losartan (L, angiotensin II type 1 receptor blocker), tempol (T, redox-cycling nitroxide) or T + L treatment (by gavage) in a six-week study. Reduction of all NOS isoforms expressions were signifi cantly improved by losartan or tempol, and correlated with proteinuria amelioration. Combined treatment induced down-regulation of constitutive NOS isoforms, whilst inducible NOS was up-regulated and followed by increased nitrite content and a signifi cant decline in the glomerular fi ltration rate. Losartan or tempol prevented ADR-induced neoexpression of vimentin in the glomeruli and tubulointerstital areas, whereas de novo vimentin expression was still observed in the atrophic tubules and in the interstitial fi broblasts and myofi broblasts in combined treatment. It can be concluded that single treatments, contrary to combined, were effective in improving NO bioavailability and slowing down the progression of CKD

EpiCRISPR targeted methylation of Arx gene initiates transient switch of mouse pancreatic alpha to insulin-producing cells

Introduction: Beta cell dysfunction by loss of beta cell identity, dedifferentiation, and the presence of polyhormonal cells are main characteristics of diabetes. The straightforward strategy for curing diabetes implies reestablishment of pancreatic beta cell function by beta cell replacement therapy. Aristaless-related homeobox (Arx) gene encodes protein which plays an important role in the development of pancreatic alpha cells and is a main target for changing alpha cell identity. Results: In this study we used CRISPR/dCas9-based epigenetic tools for targeted hypermethylation of Arx gene promoter and its subsequent suppression in mouse pancreatic αTC1-6 cell line. Bisulfite sequencing and methylation profiling revealed that the dCas9-Dnmt3a3L-KRAB single chain fusion constructs (EpiCRISPR) was the most efficient. Epigenetic silencing of Arx expression was accompanied by an increase in transcription of the insulin gene (Ins2) mRNA on 5th and 7th post-transfection day, quantified by both RT-qPCR and RNA-seq. Insulin production and secretion was determined by immunocytochemistry and ELISA assay, respectively. Eventually, we were able to induce switch of approximately 1% of transiently transfected cells which were able to produce 35% more insulin than Mock transfected alpha cells. Conclusion: In conclusion, we successfully triggered a direct, transient switch of pancreatic alpha to insulin-producing cells opening a future research on promising therapeutic avenue for diabetes management. 1 Introductio

Genotoxic potential of Cotinus coggygria Scop. (Anacardiaceae) stem extract in vivo

The intention was to evaluate the possible in vivo genotoxic potential in different cell-types, of a methanol extract obtained from the plant stem of Cotinus coggygria Scop., using the sex-linked recessive lethal (or SLRL) test and alkaline comet assay. The SLRL test, revealed the genotoxic effect of this extract in postmeiotic and premeiotic germ-cell lines. The comet assay was carried out on rat liver and bone marrow at 24 and 72 h after intraperitoneal administration. For genotoxic evaluation, three concentrations of the extract were tested, viz., 500, 1000 and 2000 mg/kg body weight (bw), based on the solubility limit of the extract in saline. Comet tail moment and total scores in the group treated with 500 mg/kg bw, 24 and 72 h after treatment, were not significantly different from the control group, whereas in the groups of animals, under the same conditions, but with 1000 and 2000 mg/kg bw of the extract, scores were statistically so. A slight decrease in the comet score and tail moment observed in all the doses in the 72 h treatment, gave to understand that DNA damage induced by Cotinus coggygria extract decreased with time. The results of both tests revealed the genotoxic effect of Cotinus coggygria under our experimental conditions

Perspektive upotrebe biljaka kao bioenergetskih useva

Bioenergy crops are cultivated specifically in order to utilize their plant mass or grains for production of liquid or solid fuels, as alternative to the existing energy sources. The paper is concerned with the possibilities of utilization of common field corps, as energy crops, in Serbian agroecologic conditions. As bioenergy sources, both new, promising crops (Panicum virgatum L., Miscanthus × giganteus Greef et Deu., Arundo donax L., Phalaris arundinacea L.) and traditional sources are presented. Perspective of development and spreading of certain bioenergy crops species will depend primarily on market conditions (mostly on: fuel and crop prices, participation of governmental subventions) and specific agrotechnical requirements of the cultivation of these crops.Биоенергетски усеви се специфично узгајају да би се њихова биљна маса или семе искористили за производњу течних или чврстих енергената, као алтернатива постојећим енергетским изворима. У раду су продискутоване могућности употребе уобичајених ратарских усева, као енергетских усева, у нашим (српским) агроеколошким условима. Приказани су и перспективни нови усеви, као и традиционални биоенергетски извори. Перспектива развоја и ширења појединих врста биоенергетских усева зависиће првенствено од кретања цена на тржишту (углавном: цена енергената, цена житарица и нивоа државних субвенција) и специфичних агротехничких захтева гајења ових усева

Specifični agrotehnički uslovi gajenja miskantusa

Miscanthus is a perrenial, rhizomatous, highly productive C4-grass, originating from Eastern Asia. Miscanthus represents a plant species convenient for intensive cultivation, the biomass of which should enable in the near future a substantial replacement of the existing energy sources by new, renewable sources, in order to minimize CO2 emission. Myscanthus belongs to so-called »bioenergetic crops«, which are specifically cultivated to be harvested and combusted in boilers, as an alternative to the existing energy sources. It is planted in spring, let to grow in the summer, and harvested in winter (between January and March). Once established, Miscanthus plantation persists 15 to 20 years. By adequate application of agricultural machines, high biomass yields (15-25 t/ha per year) may be achieved. The paper presents certain specificities of Miscanthus cultivation in comparison with other crops with the aim of introducing this promising plant species into agricultural production in Serbia.Мискантус је вишегодишња, високо продуктивна, С4-трава, пореклом из источне Азије. Mискантус представља биљну врсту подесну за интензивно гајење, која би својом биомасом требало у блиској будућности да омогући значајну супституцију постојећих енергетских извора са новим, обновљивим изворима, којим ће се смањити емисија СО2. Мискантус се убраја у групу тзв. „биоенергетских усева“, који се специфично узгајају да би се пожњели и сагорели у котловским постројењима, као алтернатива постојећим енергетским изворима. Сади се у пролеће, израсте током лета, а жање у зиму (од јануара до марта). Једном заснована култура мискантуса опстаје 15-20 година. Адекватним коришћењем стандардне пољопривредне механизације могу се остварити високи приноси биомасе (15-25 т/ха годишње). У раду су приказане одређене специфичности гајења мискантуса у односу на друге ратарске културе, а с циљем увођења у пољопривредну производњу ове перспективне биљне врсте и код нас