Optimization of laboratory conditions for biosynthesis of type A trichothecenes

Type A trichothecenes, T-2 toxin and diacetoxyscirpenol - DAS, belong to one of the most toxic groups of fusariotoxins. Although larger quantities of them can be found more often in cooler parts of Europe, regarding their metabolic characteristics and the types of illnesses they provoke, it is obvious that even smaller quantities of these toxins can cause serious health disturbances of humans and animals in climatic conditions of Serbia. Having in mind the importance of these substances, the aim of this study was to carry out the optimization of laboratory conditions under which screening of Fusarium spp. isolates from Serbia, regarding T-2 toxin and DAS production, should be done. Four cultures of Fusarium sporotrichioides originating from different regions throughout the world, were under present investigation: ITM-391 (Italy), KF-38/1 (Poland), M-1-1 (Japan) and R-2301 (Germany). According to the previous literature data, all of these isolates were T-2 toxin producers, and some of them were also DAS producers. The influence of medium composition (different C and N atoms sources microelements etc), as well as aeration (in liquid media), on biosynthesis process of these mycotoxins, in vitro conditions was investigated. In the case of most Fusarium sporotrichioides isolates, highest yields of T-2 toxin and DAS were achieved under the conditions of more intense aeration, and with the use of glucose (5 or 20%) as a C atom source. Fermentation in semi-synthetic liquid medium, using a rotary shaker, was more suitable for screening the toxicity of the fungal isolates in pure culture because of shorter period of incubation, more simpler sample preparation, obtaining less interfering materials in crude toxin extracts, and possibility for more precise definition of factors influencing the yield of trichothecenes.Trihoteceni grupe A, T-2 toksin i diacetoksiscirpenol - DAS, predstavljaju jednu od najtoksičnijih grupa fuzariotoksina. Oni se u većim koncentracijama češće mogu naći u hladnijim regionima Evrope, ali, u skladu sa njihovim karakteristikama i vrstama oboljenja koja izazivaju, jasno je da i njihove manje količine mogu dovesti do ozbiljnih zdravstvenih poremećaja kod ljudi i životinja u klimatskim uslovima Srbije. S obzirom na značaj ovih jedinjenja cilj ovog istraživanja je bio da se izvrši optimizacija laboratorijskih uslova u kojima bi se ispitivala sposobnost za biosintezu T-2 toksina i DAS-a kod Fusarium izolata iz Srbije. Istraživanjem su bile obuhvaćene 4 kulture F. sporotrichioides poreklom iz različitih zemalja sveta: ITM-391 (Italija), KF-38/1 (Poljska), M-1-1 (Japan) i R-2301 (Nemačka), za koje je prethodno opisano u literaturi da su producenti T-2 toksina, a neke i DAS-a. Ispitan je uticaj sastava podloge (različiti izvori atoma ugljenika i azota mikroelementi i sl) kao i aeracije (u slučaju tečnih podloga) na proces biosinteze ovih mikotoksina in vitro uslovima. Kod većine izolata najveći prinosi T-2 toksina i DAS-a su dobijeni u uslovima veće aeracije i pri upotrebi glukoze (5 ili 20%) kao izvora ugljenikovog atoma. Fermentacija u tečnoj podlozi se pokazala kao pogodnija metoda za testiranje toksigenosti gljivičnih izolata od prirodnog sterilnog supstrata, zbog kraćeg perioda kultivacije, dobijanja sirovih ekstrakata toksina sa manje pratećih materija, kao i mogućnosti preciznijeg definisanja faktora koji utiču na prinos trihotecena

Mycotoxins in poultry production

All poultry is sensitive to mycotoxins. This partly depends on the type, age and production categories of poultry, their living conditions and nutritive status and partly on the type, quantity and duration of mycotoxin ingestion. The presence of mycotoxins results in significant health disorders and a decrease in production performances. This leads to considerable economic loss for the poultry industry - either direct losses, i.e. death of the poultry or the indirect ones, i.e. the decrease in body mass, number and quality of eggs, greater food conversion, and immunosuppression. Immunosuppression results in increased sensitivity to infective agents and a bad vaccinal response. Morevover, mycotoxin residues in poultry meat, eggs and products derived from them pose a threat to human health. In order to prevent and reduce the negative implications of mycotoxins in the poultry production, it is necessary to create both global and national strategies for combatting mycotoxins, advance diagnostic techniques and procedures, intensify the control of food quality, introduce new limits on the maximum amount of mycotoxins allowed in food and poultry feed used for certain species and categories of animals, and synchronise it with the European standards.Sva živina je osetljiva na mikotoksine u zavisnosti od vrste, starosne i proizvodne kategorije, uslova ambijenta i nutritivnog statusa, sa jedne strane, i vrste, količine i dužine unošenja mikotoksina, sa druge strane. Prisustvo mikotoksina rezultira značajnim poremećajem zdravlja i padom proizvodnih performansi, a samim tim i značajnim ekonomskim gubicima u živinarskoj industriji, kako direktnim, koji se očituju uginućem živine, tako i indirektnim, u vidu pada telesne mase, broja i kvaliteta jaja, veće konverzije hrane i imunosupresijom. Imunosupresija rezultira povećanom osetljivošću na infektivne agense i lošim vakcinalnim odgovorom. Opasnost po ljudsko zdravlje predstavljaju rezidue mikotoksina u živinskom mesu, jajima i proizvodima dobijenim od njih. Da bi se predupredile i smanjile negativne implikacije mikotoksina u živinarskoj proizvodnji potrebno je formirati kako globalne tako i nacionalne strategije za borbu protiv mikotoksina, unaprediti dijagnostičke tehnike i procedure, pooštriti kontrolu kvaliteta hrane, uvesti nove limite za maksimalne količine mikotoksina u hrani i hranivima za pojedine životinjske vrste i kategorije i uskladiti ih sa evropskim standardima

Cutaneous effects of sea buckthorn oil emulsion

© 2014 University of Kragujevac, Faculty of Science. All rights reserved. Sea buckthorn oil (Hippophae rhamnoides L.) is medically used both externally and internally, but the external application is unsuitable due to its liquid, lipophilic and highly coloured nature. These difficulties could be overcome by a formulation of semisolid emulsion with sea buckthorn oil. Previous research on this formulation showed that it has higher wound healing potential than sea buckthorn oil, possessing an enhanced structure of liquid crystals, stability and suitability for topical use.The tested formulation shows good moisturizising eff ects and does not cause human or animal skin irritation. The study confirms that the combination of the proposed ingredients in a sea buckthorn oil emulsion is adequate and could be safe for skin application.The aim of this investigation was to completely characterizise a proposed emulsion by testing skin eff ects, such as moisturising potential, skin pH and potential to cause skin irritation.The emulsion was prepared by standard emulsifying techniques using a combination of surfactants that form an enhanced structure of liquid crystals. Approximately 40% of sea buckthorn oil was incorporated. The moisturising potential and skin pH were tested on the healthy skin of volunteers. Skin tolerance was tested on a rabbit skin model and evaluated by the Draize test.The tested emulsion containing sea buckthorn oil did not cause a significant change in skin pH, while it significantly increased skin hydration. There was an absence of edema or erythema type of irritation after 2 h, 24 h, 48 h, 72 h and 7 days of application of the emulsion with sea buckthorn oil

Cutaneous Effects of Sea Buckthorn Oil Emulsion

Ulje pasjeg trna (Hippophae rhamnoides L.) se u medicinske svrhe upotrebljava kako za eksternu tako i za internu primenu, pri čemu je eksterna primena nepogodna usled njegove tečne konzistencije, lipofi lne prirode i intenzivne obojenosti. Navedeni nedostaci bi se mogli prevazići formulacijom polučvrstih emulzija sa uljem pasjeg trna. Prethodna ispitivanja ove formulacije su pokazala da poseduje znatno veći potencijal za zarastanje rana u odnosu na ulje pasjeg trna, unapređenu strukturu tečnih kristala, stabilnost i pogodnost za lokalnu primenu

Natrijum selenit kao novi rodenticid

Rodents are the most destructive group of small mammalian pests considering the overall damage that they cause by feeding and other activities, or as vectors of many disease agents. In practice, chemical rodenticides have been the most widespread and most effective method of control of commensal (Mus musculus, Rattus norvegicus and R. rattus) and most harmful field rodent pests (Apodemus sylvaticus, A. agrarius and Microtus arvalis). After anticoagulant and vitamin D3 rodenticides, which were introduced worldwide in the 1980s, no other chemical compound has had a comparable role as a rodenticide in practice. In the past decade, commercial baits containing 0.1% sodium selenite have also been registered in Serbia in various formulations both for controlling rodents indoors and in the field. Data on sodium selenite as a rodenticide have been scarce. The present paper surveys research data reported so far, analyzing and drawing conclusions regarding the validity and feasibility of sodium selenite as a method of rodent control with reference to the available ecotoxicological data.U odnosu na ukupnu štetnost koju nanose ishranom i drugim aktivnostima, ali i kao prenosioci većeg broja prouzrokovača različitih obolenja, glodari spadaju u najštetnije vrste sitnih sisara. U praktičnim uslovima primene, rodenticidi hemijskog porekla predstavljali su najprimenljiviji i najefektniji način suzbijanja štetnih komensalnih (Mus musculus, Rattus norvegicus and R. rattus) kao i najštetnijih vrsta poljskih glodara (Apodemus sylvaticus, A. agrarius, Microtus arvalis). U odnosu na antikoagulantne rodenticide i vitamin D3, koji su uvedeni u primenu do 80-ih godina prošlog veka, u svetu, u praktičnim uslovima primene, ni jedno novo jedinjenje nije zauzelo značajniju ulogu kao rodenticid. Proteklih desetak godina u našoj zemlji registrovani su i komercijalno dostupni mamci sa sadržajem 0.1% natrijum selenita, različitih formulacija, kao rodenticidi za suzbijanje glodara u zaštićenim i uslovima otvorenog polja. Za sada je malo dostupnih podataka o natrijum selenitu kao rodenticidu. Cilj ovog rada je predstavljanje rezultata dosadašnjih istraživanja, njihova analiza i donošenje zaključaka o mogućnosti i opravdanosti primene natrijum selenita za suzbijanje glodara, sa osvrtom na dostupne ekotoksikološke podatke

Basic mechanisms of the cellular alterations in T-2 toxin poisoning: Influence on the choice and result of the therapy

T-2 mycotoxin, secondary metabolite of Fusarium fungi, is one of the most potent cytotoxic representatives of trichothecene mycotoxin type A. After ingestion, T-2 toxin affects actively dividing cells and irreversible post-mitotic cells. In our experiments, the best protective effects were produced by dexametasone (PI = 3.37) and different methylprednisolone formulations (PI = 2.43-2.64). Significant protective efficacy was shown by nimesulide (PI = 1.44) and N-acethyilcistein (PI = 1.29), but their values were higher in a combination with methylprednisolone (PI = 2.16-2.34). Radioprotector amifostine (WR-2721) expressed good protective effects (PI = 1.26) or/and different absorbent formulations, such as: activated charcoal (PI = 1.13) and various Min-a-zel® powder compounds, which are a well known zeolite clinoptilolite absorbents. Among the five zeolite regimens investigated, only Min-a-zel Plus® showed a significant protective effect (PI = 1.77). In summary, the steroidal anti-inflammatory drugs could be recommended as a regimen of choice for treatment of acute T-2 toxicosis while nonsteroidal anti-inflammatory compounds, different absorbent formulations and their combinations with antioxidants or radioprotectors could be important for the treatment of subacute and chronic T-2 toxin poisonings.T-2 mikotoksin, sekundarni metabolit gljivica iz roda Fusarium, jedan je od najtoksičnijih predstavnika trihotecenskih mikotoksina tipa A. Njegove osnovne osobine, prvenstveno velika stabilnost u prirodi, jeftina proizvodnja, teška detekcija i još uvek nepostojanje adekvatnog antidota čine ga veoma dobrim potencijalnim bojnim otrovom. Posle unošenja, u organizmu otrovane jedinke T-2 toksin se u ćelijama vezuje za receptore na ribozomima i pokreće seriju kaskadnih reakcija koje za posledicu imaju smanjenje stabilnosti gRNK i povećanu ekspresiju proinflamatornih gena koji su između ostalog odgovorni za nastanak anoreksije, gubitak telesne mase imunosupresiju, autoimunih efekata i oštećenje većine tkiva. Toksično oštećenje ciljnih organa, nastalo pod dejstvom T-2 toksina, posledica je njegovog citotoksičnog efekta na labilne ćelije i proinflamatornog efekta na stabilne ćelije u organizmu životinja i ljudi. S obzirom na napred iznete činjenice, jasno je što je u našim istraživanjima najbolji terapijski efekat, kod akutnog trovanja T-2 toksinom, postignut primenom antiinflamatornih lekova steroidne strukture, prvenstveno deksametazona (ZI = 3,37) i različitih oblika metilprednizolona (ZI = 2,43-2,64). Osim toga antiinflamatorni lekovi nesteroidne strukture ispoljili su značajan terapijski efekat, nimesulid (ZI = 1,44) i N-acetlilcistein (ZI = 1,29), ali se njihovo zaštitno dejstvo potencira u kombinaciji sa metilprednisolonom (ZI = 2,16-2,34). Terapijsku efikasnost ispoljili su radioprotektor amifostin (WR-2721) (ZI = 1,26) i/ili različiti apsorbensi. Od primenjenih apsorbenasa, kao što su aktivni ugalj (ZI = 1,13) i različiti oblici Min-a-zel-a®, najveći protektivni efekat ispoljio je Min-a-zel Plus® oblik klinoptiolinskog zeolita (ZI = 1,77). Na osnovu prikazanih rezultata, a u skladu sa činjenicom da je citotoksično i proinflamatorno dejstvo T-2 toksina u direktnoj srazmeri sa njegovom akutnom toksičnošću, u potpunosti je opravdano korišćenje visokih doza antiinflamatornih lekova steroidne strukture u terapiji akutnog trovanja T-2 toksinom. Sa druge strane, u terapiji subakutnih ili hroničnih trovanja T-2 toksinom, preporučuje se upotreba antiinflamatornih lekova nesteroidne strukture, različitih apsorbenasa, ili njihove kombinovane primene sa antioksidansima ili radioprotektorima

Selective inhibitors for JNK signalling: a potential targeted therapy in cancer

c-Jun N-terminal kinase (JNK) signalling regulates both cancer cell apoptosis and survival. Emerging evidence show that JNK promoted tumour progression is involved in various cancers, that include human pancreatic-, lung-, and breast cancer. The pro-survival JNK oncoprotein functions in a cell context- and cell type-specific manner to affect signal pathways that modulate tumour initiation, proliferation, and migration. JNK is therefore considered a potential oncogenic target for cancer therapy. Currently, designing effective and specific JNK inhibitors is an active area in the cancer treatment. Some ATP-competitive inhibitors of JNK, such as SP600125 and AS601245, are widely used in vitro; however, this type of inhibitor lacks specificity as they indiscriminately inhibit phosphorylation of all JNK substrates. Moreover, JNK has at least three isoforms with different functions in cancer development and identifying specific selective inhibitors is crucial for the development of targeted therapy in cancer. Some selective inhibitors of JNK are identified; however, their clinical studies in cancer are relatively less conducted. In this review, we first summarised the function of JNK signalling in cancer progression; there is a focus on the discussion of the novel selective JNK inhibitors as potential targeting therapy in cancer. Finally, we have offered a future perspective of the selective JNK inhibitors in the context of cancer therapies. We hope this review will help to further understand the role of JNK in cancer progression and provide insight into the design of novel selective JNK inhibitors in cancer treatment

Immune Evasion, a Potential Mechanism of Trichothecenes: New Insights into Negative Immune Regulations

Days ago, the Nobel Prize in Physiology or Medicine 2018 was awarded jointly to James P. Allison and Tasuku Honjo “for their discovery of cancer therapy by inhibition of negative immune regulation„. This news has increased the attention on immunotoxicity and immune evasion mechanisms, which are once again hot research topics. Actually, increasing lines of evidence show that trichothecene mycotoxins have a strong immunosuppressive effect. These mycotoxins suppress the host immunity and make them more sensitive to the infection of pathogens, including bacteria and viruses. However, the underlying mechanism(s) in this context is still poorly understood. Interestingly, recent work showed that an immune evasion mechanism might be involved in trichothecene immunotoxicity. In this work, we discuss the potential immune evasion mechanism in trichothecene immunotoxicity. More importantly, under these circumstances, we are pleased to compile a Special Issue entitled “Biochemistry, Molecular Biology, and Toxicology of Natural and Synthetic Toxins„ for the International Journal of Molecular Sciences (IJMS). Researchers are encouraged to share their latest interesting findings with the readers of IJMS

Histochemical evaluation of T-2 toxin-induced cardiotoxicity in rats: Semiquantitative analysis

In this study female Wistar rats were treated with T-2 toxin (1 LD50 0.23 mg/kg sc) and sacrificed on days 1, 3, 5, 7, 14, 21, 28 and 60 after the treatment. Control groups of rats were treated by saline (1 ml/kg 0.9% NaCl). At each time-schedule, control groups of animals were sacrificed, too. Pathohistological alterations of the heart were evaluated in whole visual fields stained by haematoxylin and eosin (HE), periodic acid- -Schiff's (PAS), Masson-Trichrom's (MT) and Giemsa (GIM) methods. The changes observed were scored by using semiquantitative grading scale. The heart alterations detected in T-2 toxin-treated animals ranged from focal parenchymal or hyaline degeneration (HE = 2.5 - 4.0; p lt 0.05 vs. control) to diffuse necrosis of muscle cells (HE = 5.0; p lt 0.05 vs. control and 1st day after T-2 treatment). The myofibrils were slightly PAS-positive during the first week of the study (PAS = 2.0 - 3.2; p lt 0.05 vs. control and 1st day after T-2 treatment), while a diffuse distribution of glycogen granules in endo- and perimisium were observed from day 21 to 60 in the whole heart' tissue (PAS = 4.0; p lt 0.05 vs. control and 1st day after T-2 treatment). Massive hemorrhagic foci associated with diffuse accumulation and degranulation of MCs were the most intensive from day 28 to 60 of the study (MT = 5.0; p lt 0.05 vs. control and 1st day after T-2 treatment). During the whole study period, irregular distribution of glycogen granules, intensity and total number of haemorrhages were in correlation with the degree of heart structural lesions, which showed the highest coefficient of correlation (r = 0.8750; p lt 0.001). Our results indicate that basic histohemical methods can be a useful tool for evaluation of T-2 toxin-induced cardiac damage, which is probably a result of complex inflammatory mechanisms, eventually leading to vascular lesions and myocardial necrosis, as well as for some potential cardioprotectors in the future.U ovom radu su ispitani toksični efekti na srcu Wistar pacova akutno trovanih T-2 toksinom. Životinje, jednokratno tretirane T-2 toksinom u dozi od 0,23 mg/kg sc (1 LD50), žrtvovane su 1, 3, 5, 7, 14, 21, 28. i 60. dana posle aplikacije otrova. Kontrolne grupe životinja tretirane su fiziološkim rastvorom (1 ml/kg 0,9% NaCl) i žrtvovane u istim vremenskim intervalima. Procena patohistoloških promena izvršena je na uzorcima tkiva srca, bojenih standardnim histohemijskih metodama: hematoksilin i eozin (HE), Gimza (GIM), perjodna kiselina Schiff-ov reagens (PAS) i Masson trichrom (MT), primenom semikvantitativne analize. U srcu pacova tretiranih T-2 toksinom uočene su promene od fokalne parenhimatozne i hijaline degeneracije miofibrila (HE = 2,5-4,0; r lt 0,05 u poređenju sa kontrolom) do fokalne ili difuzne nekroze mišićnih ćelija (HE = 5,0; r lt 0,05 u poređenju sa kontrolom i 1. danom posle aplikacije T-2 toksina). Tokom prve nedelje ispitivanja miofibrile su bile blago PAS-pozitivne (PAS = 2,0-3,2; r lt 0,05 u poređenju sa kontrolom i 1. danom posle aplikacije T-2 toksina), dok je difuzna distribucija granula glikogena u endo- i perimizijumu zapažena od 21. do 60. dana (PAS = 4,0; p lt 0,05 u poređenju sa kontrolom i 1. danom posle aplikacije T-2 toksina). Masivna hemoragična polja, okružena mnogobrojnim inflamatornim ćelijama, naročito su izražena u periodu od 28. do 60. dana ispitivanja (MT = 5,0; p lt 0,05 u poređenju sa kontrolom i 1. danom posle aplikacije T-2 toksina). Tokom celog perioda ispitivanja, nepravilna distribucija granula glikogena, intenzitet krvarenja i ukupan broj mastocita su bili u korelaciji sa stepenom oštećenja tkiva srca (r = 0,8750; p lt 0,001). Dobijeni rezultati su potvrdili ranije iznetu tezu da su kardiotoksični efekti T-2 toksina verovatno rezultat kompleksnih inflamatornih mehanizama