Curcuma Longa Extract as a Sensitizer for Singlet Oxygen Generation

In this work, the spectral study of aqueous extract of Curcuma Longa (Turmeric) to determine the photodynamic properties. It is established that due to the absorption extract light of wavelength 400-450 nm and intensive fluorescence in the red region of the spectrum, this extract can be used as a sensitizer of singlet oxygen (1

Non-Western Peacekeeping as a Factor of a Multipolar World: Outlines of Research Program

This paper describes the contours of a research program on peacekeeping and peacebuilding, representing the interests of Non-Western countries (the world’s majority). The article is based on both individual developments of its expert authors in the theory and practice of peacekeeping, international law and development cooperation, as well as on generalized conclusions of eight international workshops on Non-Western peacekeeping, held by the Department of Theory and History of International Relations of the RUDN University in 2020-2021 with the participation of leading Russian and international experts. Particular attention is paid to the current moment in international peacekeeping associated with the “power transit” (from the United States to China, and more broadly, from the West to the Non-West) and the power vacuum observed in a number of regions. Conclusions are drawn about the crisis of humanitarian intervention and the system of liberal peacekeeping in general. At the same time, the remaining instruments of Western structural power in the field of peacekeeping are examined in detail, covering both personnel representation in the UN and the practice of ‘penholding,’ as well as the discursive hegemony of the “Collective West.” The main directions in the development of Non-Western academic discourse in the field of peacemaking and peacebuilding are explored in the context of building a multipolar world. Special attention is paid to the problems of regional human rights systems in the context of the protection of civilians and post-conflict peacebuilding. The study concludes that Non-Western countries have a significant influence on the formation of international norms in the field of peacekeeping (rule-changers), but so far do not act as norm-setting actors in world politics (rule-makers)

Necrostatin-1 Analogues: Critical Issues on the Specificity, Activity and In Vivo Use in Experimental Disease Models

Necrostatin-1 (Nec-1) is widely used in disease models to examine the contribution of receptor-interacting protein kinase (RIPK) 1 in cell death and inflammation. We studied three Nec-1 analogs: Nec-1, the active inhibitor of RIPK1, Nec-1 inactive (Nec-1i), its inactive variant, and Nec-1 stable (Nec-1s), its more stable variant. We report that Nec-1 is identical to methyl-thiohydantoin-tryptophan, an inhibitor of the potent immunomodulatory enzyme indoleamine 2,3-dioxygenase (IDO). Both Nec-1 and Nec-1i inhibited human IDO, but Nec-1s did not, as predicted by molecular modeling. Therefore, Nec-1s is a more specific RIPK1 inhibitor lacking the IDO-targeting effect. Next, although Nec-1i was ∼100 × less effective than Nec-1 in inhibiting human RIPK1 kinase activity in vitro, it was only 10 times less potent than Nec-1 and Nec-1s in a mouse necroptosis assay and became even equipotent at high concentrations. Along the same line, in vivo, high doses of Nec-1, Nec-1i and Nec-1s prevented tumor necrosis factor (TNF)-induced mortality equally well, excluding the use of Nec-1i as an inactive control. Paradoxically, low doses of Nec-1 or Nec-1i, but not Nec -1s, even sensitized mice to TNF-induced mortality. Importantly, Nec-1s did not exhibit this low dose toxicity, stressing again the preferred use of Nec-1s in vivo. Our findings have important implications for the interpretation of Nec-1-based data in experimental disease models

Generation and physiological roles of linear ubiquitin chains

Ubiquitination now ranks with phosphorylation as one of the best-studied post-translational modifications of proteins with broad regulatory roles across all of biology. Ubiquitination usually involves the addition of ubiquitin chains to target protein molecules, and these may be of eight different types, seven of which involve the linkage of one of the seven internal lysine (K) residues in one ubiquitin molecule to the carboxy-terminal diglycine of the next. In the eighth, the so-called linear ubiquitin chains, the linkage is between the amino-terminal amino group of methionine on a ubiquitin that is conjugated with a target protein and the carboxy-terminal carboxy group of the incoming ubiquitin. Physiological roles are well established for K48-linked chains, which are essential for signaling proteasomal degradation of proteins, and for K63-linked chains, which play a part in recruitment of DNA repair enzymes, cell signaling and endocytosis. We focus here on linear ubiquitin chains, how they are assembled, and how three different avenues of research have indicated physiological roles for linear ubiquitination in innate and adaptive immunity and suppression of inflammation

Bacterial porin disrupts mitochondrial membrane potential and sensitizes host cells to apoptosis

The bacterial PorB porin, an ATP-binding beta-barrel protein of pathogenic Neisseria gonorrhoeae, triggers host cell apoptosis by an unknown mechanism. PorB is targeted to and imported by host cell mitochondria, causing the breakdown of the mitochondrial membrane potential (delta psi m). Here, we show that PorB induces the condensation of the mitochondrial matrix and the loss of cristae structures, sensitizing cells to the induction of apoptosis via signaling pathways activated by BH3-only proteins. PorB is imported into mitochondria through the general translocase TOM but, unexpectedly, is not recognized by the SAM sorting machinery, usually required for the assembly of beta-barrel proteins in the mitochondrial outer membrane. PorB integrates into the mitochondrial inner membrane, leading to the breakdown of delta psi m. The PorB channel is regulated by nucleotides and an isogenic PorB mutant defective in ATP-binding failed to induce delta psi m loss and apoptosis, demonstrating that dissipation of delta psi m is a requirement for cell death caused by neisserial infection

Development and certification of a pharmacopoeial reference standard for primary structure identification of purified recombinant interferon beta-1b by peptide mapping

Medicines based on recombinant human interferons (rhIFNs) beta-1a and beta-1b are used as first-line treatment of multiple sclerosis. Meanwhile, rhIFN beta-1a and beta-1b have structural differences associated with the eukaryotic or prokaryotic expression systems, respectively. Pharmacopoeias require identification of the primary structure of recombinant proteins by peptide mapping, which involves the use of reference material. Currently, there is no international reference standard available for rhIFN beta-1b structural identification. The aim of the study was development and certification of a pharmacopoeial reference standard for identification of the amino acid sequence of purified rhIFN beta-1b by peptide mapping. Materials and methods: rhIFN beta-1b produced by GENERIUM and endoproteinase Glu-C from Staphylococcus aureus V8 were used in the study. The peptide mapping was performed using reverse-phase high-performance liquid chromatography (RP HPLC) and high-resolution mass spectrometry. Statistical evaluation of the results included calculation of the arithmetic mean, standard deviation, and coefficient of variation. Results: the authors developed and certified a Russian Pharmacopoeia reference standard for structural identification of rhIFN beta-1b (PhRS 3.2.00447). The certified characteristic is the range of retention times of characteristic peaks: the absolute retention time was 42.0–43.2 for the third (reference) peak, the relative retention time was 0.61–0.66 for the first peak, 0.68–0.73 for the second peak, 1.04–1.06 for the fourth peak, 1.14–1.15 for the fifth peak, 1.22–1.24 for the sixth peak, and 1.29–1.30 for the seventh peak. Conclusions: the authors developed requirements for the rhIFN beta-1b pharmacopoeial reference standard. The material chosen as the candidate reference standard was an intermediate rhIFN beta-1b product sampled before addition of human serum albumin. The quality control was carried out in accordance with the developed specification. The authors analysed the amino acid sequence of the molecule, confirmed the presence of the disulfi e bond, and obtained the certifi d characteristic of the reference standard. Comparative analysis of the peptide maps of the certified rhIFN beta-1b pharmacopoeial reference standard and the rhIFN beta-1a reference standard revealed differences between the maps, and, therefore, confirmed the relevance of the developed reference standard

Organometallic iridium(III) anticancer complexes with new mechanisms of action: NCI-60 screening, mitochondrial targeting, and apoptosis

Platinum complexes related to cisplatin, cis-[PtCl2(NH3)2], are successful anticancer drugs; however, other transition metal complexes offer potential for combating cisplatin resistance, decreasing side effects, and widening the spectrum of activity. Organometallic half-sandwich iridium (IrIII) complexes [Ir(Cpx)(XY)Cl]+/0 (Cpx = biphenyltetramethylcyclopentadienyl and XY = phenanthroline (1), bipyridine (2), or phenylpyridine (3)) all hydrolyze rapidly, forming monofunctional G adducts on DNA with additional intercalation of the phenyl substituents on the Cpx ring. In comparison, highly potent complex 4 (Cpx = phenyltetramethylcyclopentadienyl and XY = N,N-dimethylphenylazopyridine) does not hydrolyze. All show higher potency toward A2780 human ovarian cancer cells compared to cisplatin, with 1, 3, and 4 also demonstrating higher potency in the National Cancer Institute (NCI) NCI-60 cell-line screen. Use of the NCI COMPARE algorithm (which predicts mechanisms of action (MoAs) for emerging anticancer compounds by correlating NCI-60 patterns of sensitivity) shows that the MoA of these IrIII complexes has no correlation to cisplatin (or oxaliplatin), with 3 and 4 emerging as particularly novel compounds. Those findings by COMPARE were experimentally probed by transmission electron microscopy (TEM) of A2780 cells exposed to 1, showing mitochondrial swelling and activation of apoptosis after 24 h. Significant changes in mitochondrial membrane polarization were detected by flow cytometry, and the potency of the complexes was enhanced ca. 5× by co-administration with a low concentration (5 μM) of the γ-glutamyl cysteine synthetase inhibitor L-buthionine sulfoximine (L-BSO). These studies reveal potential polypharmacology of organometallic IrIII complexes, with MoA and cell selectivity governed by structural changes in the chelating ligands

Essential versus accessory aspects of cell death: recommendations of the NCCD 2015

Cells exposed to extreme physicochemical or mechanical stimuli die in an uncontrollable manner, as a result of their immediate structural breakdown. Such an unavoidable variant of cellular demise is generally referred to as ‘accidental cell death’ (ACD). In most settings, however, cell death is initiated by a genetically encoded apparatus, correlating with the fact that its course can be altered by pharmacologic or genetic interventions. ‘Regulated cell death’ (RCD) can occur as part of physiologic programs or can be activated once adaptive responses to perturbations of the extracellular or intracellular microenvironment fail. The biochemical phenomena that accompany RCD may be harnessed to classify it into a few subtypes, which often (but not always) exhibit stereotyped morphologic features. Nonetheless, efficiently inhibiting the processes that are commonly thought to cause RCD, such as the activation of executioner caspases in the course of apoptosis, does not exert true cytoprotective effects in the mammalian system, but simply alters the kinetics of cellular demise as it shifts its morphologic and biochemical correlates. Conversely, bona fide cytoprotection can be achieved by inhibiting the transduction of lethal signals in the early phases of the process, when adaptive responses are still operational. Thus, the mechanisms that truly execute RCD may be less understood, less inhibitable and perhaps more homogeneous than previously thought. Here, the Nomenclature Committee on Cell Death formulates a set of recommendations to help scientists and researchers to discriminate between essential and accessory aspects of cell death

Разработка и валидация методики пептидного картирования инновационного препарата ингибитора С1 эстеразы

Peptide mapping is a key method for studying the primary structure of proteins. With its sensitivity to the slightest changes in the covalent structure of a protein, this method is applicable both to medicinal product identification at the control stage and to production process stability monitoring.The aim of the study was to develop and validate a peptide-mapping procedure for the identification of a novel highly glycosylated recombinant C1 esterase inhibitor.Materials and methods. The authors studied recombinant human C1 esterase inhibitor products and trypsin. The study involved peptide mapping using reverse-phase high-performance liquid chromatography and high-resolution mass spectrometry. The following statistics were calculated to evaluate the results: mean, standard deviation, and coefficient of variation. The validation parameters included specificity, precision, and robustness.Results. The authors tested several variants of sample preparation for tryptic digests, including additional N-glycanase treatment and complete deglycosylation, and established the optimal conditions for sample preparation and chromatographic separation of C1 esterase inhibitor peptides to obtain consistent chromatographic profiles (peptide maps). The authors identified characteristic peaks and the corresponding relative retention time and area ranges. The absolute retention time of the second (characteristic) peak was approximately 16.5–16.9 minutes. The relative retention times were 2.14–2.21 for peak 9, 2.55–2.64 for peak 12, 2.97–3.14 for peak 14, 3.11–3.29 for peak 15, and 6.20–6.63 for peak 28.Conclusions. The authors developed a peptide-mapping procedure for C1 esterase inhibitors and optimised the conditions to achieve an over 18-hour reduction in sample preparation time. This procedure met the established acceptance criteria for specificity, precision, and robustness.Пептидное картирование является одним из ключевых методов изучения первичной структуры белка. Метод чувствителен даже к малейшим изменениям в ковалентной структуре белка, что позволяет использовать его для проверки подлинности препарата на стадии контроля и мониторинга стабильности производственного процесса.Цель работы: разработка и валидация методики пептидного картирования для подтверждения подлинности инновационного высокогликозилированного рекомбинантного белка — ингибитора С1 эстеразы.Материалы и методы: рекомбинантный ингибитор С1 эстеразы человека, трипсин. Исследование проводили методом пептидного картирования с использованием обращенно-фазовой высокоэффективной жидкостной хроматографии (ОФ ВЭЖХ) и метода масс-спектрометрии высокого разрешения. Результаты оценивали с применением статистических методов расчета среднего арифметического, стандартного отклонения, коэффициента вариации. Методику валидировали по показателям: специфичность, прецизионность и устойчивость.Результаты: апробированы разные варианты пробоподготовки трипсинолизатов, включая дополнительную обработку белка N-гликаназой и полное дегликозилирование. Подобраны условия пробоподготовки и хроматографического разделения пептидов ингибитора С1 эстеразы с получением стабильного профиля пептидной карты. Разработаны и определены реперные пики, а также диапазоны их относительных времен удерживания и относительной площади. Абсолютное время удерживания второго (референтного) пика составило 16,5–16,9 мин. Относительное время удерживания пика 9 — 2,14–2,21, пика 12 — 2,55–2,64, пика 14 — 2,97–3,14, пика 15 — 3,11–3,29 и пика 28 — 6,20–6,63.Выводы: разработана методика пептидного картирования ингибитора С1 эстеразы. Оптимизация условий методики позволила сократить время пробоподготовки более чем на 18 ч. Разработанная методика по валидационным характеристикам специфичности, прецизионности и устойчивости соответствовала установленным критериям приемлемости

High Throughput Ratio Imaging to Profile Caspase Activity: Potential Application in Multiparameter High Content Apoptosis Analysis and Drug Screening

Recent advancement in the area of green fluorescent protein techniques coupled with microscopic imaging has significantly contributed in defining and dissecting subcellular changes of apoptosis with high spatio-temporal resolution. Although single cell based studies using EGFP and associated techniques have provided valuable information of initiation and hierarchical changes of apoptosis, they are yet to be exploited for multiparameter cell based real time analysis for possible drug screening or pathway defining in a high throughput manner. Here we have developed multiple cancer cell lines expressing FRET sensors for active caspases and adapted them for high throughput live cell ratio imaging, enabling high content image based multiparameter analysis. Sensitivity of the system to detect live cell caspase activation was substantiated by confocal acceptor bleaching as well as wide field FRET imaging. Multiple caspase-specific activities of DEVDase, IETDase and LEHDase were analysed simultaneously with other decisive events of cell death. Through simultaneous analysis of caspase activation by FRET ratio change coupled with detection of mitochondrial membrane potential loss or superoxide generation, we identified several antitumor agents that induced caspase activation with or without membrane potential loss or superoxide generation. Also, cells that escaped the initial drug-induced caspase activation could be easily followed up for defining long term fate. Employing such a revisit imaging strategy of the same area, we have tracked the caspase surviving fractions with multiple drugs and its subsequent response to retreatment, revealing drug-dependent diverging fate of surviving cells. This thereby indicates towards a complex control of drug induced tumor resistance. The technique described here has wider application in both screening of compound libraries as well as in defining apoptotic pathways by linking multiple signaling to identify non-classical apoptosis inducing agents, the greatest advantage being that the high content information obtained are from individual cells rather than being population based