Towards understanding intermolecular interactions in hydantoin derivatives: the case of cycloalkane-5-spirohydantoins tethered with a halogenated benzyl moiety

A series of cycloalkane-5-spirohydantoins bearing a halogeno substituted benzyl group (X = Cl and Br) in position 3 has been synthesized and their structures (1-6) have been determined by a single crystal X-ray diffraction method. These compounds have multiple functional groups, which allow greater competition and/ or cooperation among the different intermolecular interactions in the formation of their crystal structures. The molecules are linked together by paired N-H... O hydrogen bonds in R22(8) rings, while the CH. O interactions lead to their further association into double chains. The contribution of the cycloalkyl ring depends on its conformational flexibility and the multiple C-H donor implications. In the case of compounds 1-4 bearing the cyclopentyl or the cyclohexyl ring, halogen bonding (X...O) interactions give rise to a supramolecular pseudo-hexagonal network. In addition, the C-H... X interactions with a higher degree of multifurcation at the halogen acceptor have an important role in the formation of the crystal structure. Regarding compounds 5 and 6 with the cycloheptane ring, the X. O interaction is absent, and along with the C-H. X interactions, these compounds realize an alternative crystal structure with an emphasis on the X. p interactions. The lattice energies of all these crystal structures, as well as the intermolecular pair energies, have been calculated using PIXEL and further partitioned into coulombic, dispersive, polarization and repulsive factors. The crystal structures have also been subjected to Hirshfeld surface analysis which reveals that approximately 75% of the close contacts correspond to relatively weak interactions. The application of both concepts has provided a new insight into the relationship between the molecular interactions and crystal structures of the hydantoin derivatives.This is the peer-reviewed version of the following article: Crystengcomm, 2017, 19, 3, 469-483 [https://dx.doi.org/10.1039/C6CE02210C][http://cer.ihtm.bg.ac.rs/handle/123456789/2204

Precision glycan supplementation: A strategy to improve performance and intestinal health of laying hens in high‐stress commercial environments

In the dynamic world of animal production, many challenges arise in disease control, animal welfare and the need to meet antibiotic‐free demands. Emerging diseases have a significant impact on the poultry industry. Managing gut microbiota is an important determinant of poultry health and performance. Introducing precision glycans as feed additives adds another dimension to this complex environment. The glycans play pivotal roles in supporting gut health and immunological processes and are likely to limit antibiotic usage while enhancing intestinal well‐being and overall poultry performance. This study explores precision glycan product as a feed additive supplemented at a continuous dose of 900 g per tonne of feed, in a free‐range production system on a large commercial farm. Forty thousand 17‐week‐old pullets were randomly allocated to one of two separated sections of the production shed, with individual silos and egg‐collecting belts. The flock performance, gut microbiota and its functionality were analysed throughout the laying cycle until 72 weeks of age. The results demonstrated that introducing precision glycans improved a range of performance indicators, including reduced cumulative mortality, especially during a major smothering event, where the birds pile up until they suffocate. There was also significantly increased hen‐housed egg production, reduced gut dysbiosis score and undigested feed, increased number of goblet cells and improved feed conversion ratio. Additionally, microbiota analysis revealed significant changes in the composition of the gizzard, ileum content, ileum mucosa, and caecal and cloacal regions. Overall, the findings suggest that precision glycans have the potential to enhance poultry egg production in challenging farming environments

Localization of neurotransmitter positive elements in rat ovary

The aim of this work was to investigate the distribution of neurotransmitter positive elements in the ovaries of two-month-old female rats in estrus using histochemistry and immunohistochemistry. Acetylcholinesterase (AChE)-positive fibers were demonstrated in the interfollicular tissue, theca externa, mesovarium and hilum, while intracellular deposits were found in granulosa cells. Dopamine (DA)-positive reaction was demonstrated in cortical nerve bundles, in fine fiber networks between and around follicles or secondary interstitial cells. Delicate 5-hydroxytriptamine (5-HT)-positive fibers were present under the surface epithelium, and 5-HT-positive cells in the hilum, medulla and in the mesovarium. Gamma-aminobutyric acid (GABA) immunostaining was present in the cytoplasm of granulosa cells and in the hilum and mesovarium. Our results confirm that neurotransmitter supply of the ovary is not only via extrinsic innervation and that intragonadal sources have a role in their synthesis

Lokalizacija monoaminskih neurotransmitera u jajnicima i jajovodima pacova tokom polnog sazrevanja

The aim of this study was to investigate the localization and distribution of sympathetic positive structures in the female gonads and oviducts of 15 30 and 60-day-oldAO rats. Histofluorescence and immunohistochemistry methods were used to determine their distribution in the ovary and oviduct, as well as for identification of dopamine and serotonin within sympathetic positive structures. Total monoamine positive structures (fibers and cells) were mainly localized under the surface epithelium, between follicles, especially surrounding groups of primary follicles and between secondary interstitial cells. The distribution of dopamine (DA) immunolabelled fibers and cells was in accordance with the distribution of total monoaminergic structures detected using histofluorescence. However, the density of structures labeled with DA antibodies was lower compared to total catecholamine positive structures detected by the fluorescence method. Delicate serotonin (5-HT) positive fibers were present mainly under the surface epithelium and in interstitial tissue between the cortex and medulla. In the hilum and medulla 5-HT positive cells were found perivascularly, while a dense population of 5-HT positive cells was found in the oviduct and mesovarium in 60-day-old animals. No corpus luteum cells were labelled using either of the two methods. Our findings corroborate observations that the monoamine supply of the ovary is not exclusively via extrinsic innervation and that intragonadal sources have an important role in their synthesis. Furthermore, the intraovarian localization of these elements suggests that monoamines exert direct or indirect effects on ovarian function.Cilj našeg rada je bio ispitivanje lokalizacije i distribucije struktura pozitivnih na monoaminske neurotransmitere u jajnicima i jajovodima pacova. Za identifikaciju neurotransmitera u jajnicima i jajovodima 15, 30 i 60 dana starih AO pacova koristili smo histofluorescenciju (ukupni monoamini) i imunocitohemiju (dopamin i serotonin). Pozitivne monoaminergičke strukture prisutne su između folikula, naročito oko primarnih folikula, kao i između sekundarnih intersticijalnih ćelija. U mezoovarijumu i jajovodu 30 i 60 dana starih životinja zapažaju se fluorescentne ćelije i vlakna. Dopaminergične strukture su prisutne na istim mestima, ali njihova gustina je manja ako se uporede sa strukturama pozitivnim na ukupne monoamine. Retka serotonin-pozitivna vlakna zapažaju se uglavnom ispod klicinog epitela i u intersticijumu između kore i srži jajnika. Kod 30 i 60 dana starih ženki u hilusu i srži, pretežno oko krvnih sudova, nalaze se serotonin pozitivne ćelije, dok se u mezoovarijumu i jajovodu nalazi gusta populacija pozitivnih ćelija. Ni jednom od primenjenih metoda nije uočeno prisustvo monoamina u žutom telu. Naši rezultati potvrduju da neurotransmiteri u jajnicima i jajovodima ne potiču samo iz nervnih terminala, već da značajnu ulogu u njihovoj sintezi imaju intragonadalni izvori. Lokalizacija ovih elemenata pokazuje da monoaminski neurotransmiteri mogu ispoljavati direktan i!i indirektan uticaj na funkciju jajnika

Apoptosis as form of natural ovarian cell death

Different hormones, cytokines, the absence of growth factors, and others, are some of the signals for initiating apoptosis in ovarian cells. Each of them in its own way, trigger apoptosis as a form of death in which the cell actively participates by precisely implementing a genetically programmed sequence of biochemical and morphological changes which lead to selfdestruction. Apoptosis is a physiological form of death, which helps establish a dynamic balance among proiliferation, differenciation, and death of ovarian cells. It has been confirmed so far that follicular cells oocytes, cells of the germinal epithelium, theca cells, and corpus luteum cells die through apoptosis. The physiological deaths of these cells are an integral part of normal ovarian function, both during intrauterine and postnatal life. Namely, during intrauterine ovarian development, about half the total number of germinative cells (future oocytes) die through apoptosis and their population is gradually reduced after birth by so-called selection of follicles which will continue further growth (folliculogenesis) and the apoptosis of cells of those follicles which will be subjected to atresion. Most ovarian cells die by apoptosis continuously until the end of the reproductive life period of healthy females, and some can continue dieing in this way until the death of the given individual (e.g. germinal epithelium cells)

The influence of the structure on the antiproliferative activity of the cycloalkanespiro-5-hydantoin derivatives

U okviru proučavanja uticaja strukture na biološku aktivnost derivata cikloalkanspiro-5-hidantoina, u radu je testirana citotoksičnost novih serija jedinjenja: 3-(4-supstituisanih benzil)-1,3- -diazaspiro[4.5]dekan-2,4-diona i 3-(4-supstituisanih benzil)-1,3-diazaspiro[4.6] undekan-2,4- diona. Citotoksična aktivnost određena je MTT testom prema ćelijskoj liniji humanog karcinoma dojke (MDA-MB-231). Strukturne karakteristike jedinjenja su određene rendgenskom strukturnom analizom kao i odgovarajućim spektroskopskim metodama. Testirana jedinjenja su pokazala statistički značajnu antiproliferativnu aktivnost prema ćelijskoj liniji MDA-MB-231 u proučavanom opsegu koncentracija. Naročito su se istakli derivati koji u okviru svoje strukture sadrže kao supstituente atome halogena i nitro-grupu. Rezultati su upoređeni sa prethodno određenom antiproliferativnom aktivnošću za 3-(4-supstituisane benzil)-5,5-difenilhidantoine. Diskutovan je uticaj strukture na antiproliferativnu aktivnost proučavanih jedinjenja.In order to investigate the influence of the structure on the antiproliferative activity of the cycloalkanespiro-5-hydantoine derivatives, the cytotoxity of the new series of compounds: 3-(4- substituted benzyl)-1,3-diazaspiro[4.5]decane-2,4-dione and 3-(4-substituted benzyl)-1,3- -diazaspiro[4.6]undecane-2,4-dione has been tested. Cytotoxic activity was determined by the MTT assay againist the cell line of human breast cancer (MDA-MB-231). The structural characteristics of the compounds are determined by X-ray structural analysis, as well as by appropriate spectroscopic methods. The tested compounds showed statistically significant antiproliferative activity to the MDA-MB-231 cell line in the studied concentration range. Among the most active are derivatives containing as substituents halogen atoms and a nitro group. The results were compared with a predetermined antiproliferative activity for 3-(4-substituted benzil)-5,5- -diphenylhydantoines. The influence of structure on the antiproliferative activity of the studied compounds is also discussed

Supramolecular architectures of selected xanthenedione derivatives

The wide range of pharmacological activities (e.g. antiviral, antifungal, antibacterical, antiinflamatory, leishmanicidal and antidepresant) has already been attributed to the xanthenediones, a group of synthetic heterocyclic compounds possessing a pyran nucleus fused on either side with cyclohex-2-enone rings [1]. In this work, two 3,3,6,6- tetramethyl-9-substituted-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-diones (Figure 1) were synthesized and their crystal stuctures were determined by single crystal X-ray diffraction. The main structural feature in compound 1 is a supramolecular chain along the a-axis formed by O4–H4···O2 hydrogen bond and C13–H13···O4 and Br1···Br2 interactions between the adjacent asymmetric units, while the formation of supramolecular network is further achieved by C–H···π interactions between the adjacent chains. The main motif in 2 is a dimer formed via O4–H4···O2 hydrogen bond and Cl1···π interactions. The neighbouring dimers are connected through strong C7– H7A···π interactions, thus resulting in formation of a zigzag chain parallel to the c-axis. Weak C–H···π interactions link the adjacent chains into a supramolecular layer. This work may provide a basis for design of new biologically active xanthenediones both at the molecular and supramolecular level

Role of intermolecular interactions in the self-assembly and biorecognition of a spirohydantoin derivative

Sintetisan je racemski derivat spirohidantoina, koji poseduje tetralinsku i 4- metoksibenzil-grupu, a zatim je određena njegova kristalna struktura. Hijerarhijski razvoj kristalnog pakovanja diskutovan je sa aspekta kooperativnosti homo- i heterohiralnih dimernih motiva koji odražavaju različite intermolekulske interakcije. Specifična strukturna karakteristika proučavanog jedinjenja jesu naizmenično postavljeni dvostruki slojevi. Veliki broj kontaktnih fragmenata u okruženju tetralinske grupe predstavlja posledicu veće kontaktne površine. Sa druge strane, 4-metoksibenzil-grupa obezbeđuje veći doprinos ukupnoj stabilizaciji. Što se tiče farmakološkog potencijala proučavanog jedinjenja, izvršena je simulacija vezivanja molekula za dopaminski receptor D3 i enzim IRAK 4 (eng. Interleukin-1 Receptor-Associated Kinase 4). Ukupan broj aminokiselinskih ostataka koji stupaju u interakciju sa 4-metoksibenzil-grupom je nešto veći od broja aminokiselinskih ostataka u okruženju tetralinske grupe. Usled veće fleksibilnosti, 4-metoksibenzil-grupa se lakše adaptira za uspostavljanje interakcija sa biološkim ciljevima.Sintetisan je racemski derivat spirohidantoina, koji poseduje tetralinsku i 4- metoksibenzil-grupu, a zatim je određena njegova kristalna struktura. Hijerarhijski razvoj kristalnog pakovanja diskutovan je sa aspekta kooperativnosti homo- i heterohiralnih dimernih motiva koji odražavaju različite intermolekulske interakcije. Specifična strukturna karakteristika proučavanog jedinjenja jesu naizmenično postavljeni dvostruki slojevi. Veliki broj kontaktnih fragmenata u okruženju tetralinske grupe predstavlja posledicu veće kontaktne površine. Sa druge strane, 4-metoksibenzil-grupa obezbeđuje veći doprinos ukupnoj stabilizaciji. Što se tiče farmakološkog potencijala proučavanog jedinjenja, izvršena je simulacija vezivanja molekula za dopaminski receptor D3 i enzim IRAK 4 (eng. Interleukin-1 Receptor-Associated Kinase 4). Ukupan broj aminokiselinskih ostataka koji stupaju u interakciju sa 4-metoksibenzil-grupom je nešto veći od broja aminokiselinskih ostataka u okruženju tetralinske grupe. Usled veće fleksibilnosti, 4-metoksibenzil-grupa se lakše adaptira za uspostavljanje interakcija sa biološkim ciljevima

Self-discriminating assembly and biorecognition of a spirohydantoin derived from α-tetralone

The hierarchical development of the crystal structure of racemic 3-(4-methoxybenzyl)-6,7- benzo-1,3-diazaspiro[4.5]decane-2,4-dione was analyzed through cooperativity of various homo and heterochiral dimeric motifs associated with the presence of different intermolecular interactions, namely strong N–H···O and weaker C–H···O, C–H···π and PILOs.1 Although a bigger number of the contacts in the environment of the tetralin unit results from its larger contact surface, the 4-methoxybenzyl unit provides a greater contribution to the overall stabilization. In addition, the investigated compound is identified as a potential inhibitor of kinase enzymes and AG protein-coupled receptors, with a slightly higher affinity for the later enzyme. An analysis of the nature of the amino acid residues around the tetralin and 4-methoxy benzyl units revealed that interactions with nonpolar groups are the most prevalent and even more numerous than interactions with other amino acid residues (polar, positive and negative)

N-Acetyl-L-cysteine enhances ex-vivo amplification of deciduous teeth dental pulp stem cells

Objective: Obtaining high number of stem cells is of interest for cell based therapies. N-Acetyl-L-cysteine (NAC) acts as a source of sulfhydryl groups and an anti-oxidative agent. The aim of this study was to test different NAC concentration on proliferation and differentiation of deciduous teeth dental pulp stem cells (DTSCs) in vitro as well as to define the possible underlining mechanism of its effect. Design: Number of viable, apoptotic and senescent DTSCs was determined after addition of NAC (0.1 mM, 1.0 mM, 2.0 mM). Also, cell cycle analysis, HIF1-alpha expression, LDH isoenzymes, superoxide-dismutase (SOD) and catalase (CAT) activity, sulfhydryl groups content, the level of lipids' and proteins' oxidative damage and differentiation capacity of NAC treated DTSCs was determined. Results: DTSCs expressed HIP-1 alpha in all conditions. The lowest NAC dose (0.1 mM) increased the number of DTSCs by one fifth comparing to the control, most likely stimulating entry of cells into S phase of cell cycle and enhancing the activity of LDH5 isoenzyme. The highest NAC dose (2 mM) inhibited DTSCs proliferation. Also, DTSCs had the lowest level of oxidative damage with 0.1 mM NAC. All tested NAC concentrations enhanced DTSCs osteo-chondrogenesis. Conclusion: The lowest NAC dose exerted significant positive effect on DTSCs proliferation as well as antioxidative protection creating beneficial environment for stem cells in vitro cultivation especially when their clinical use is important for stimulation of osteo-chondrogenesis