Secondary metabolites of co-culture of Alternaria alternate YX-25 and Streptomyces exfoliatus YX-32 / 中草药

Objective To study the secondary metabolites of the co-culture of fungus Alternaria alternata YX-25 and Streptomyces exfoliatus YX-32 isolated from mangrove mud in Yunxiao Country of Fujian Province. Methods The compounds were purified by silica gel and Sephadex LH-20, followed by semi-preparative chromatography. The structures of the compounds were determined by MS and NMR. Results Nine compounds were isolated from the crude extract, which were identified as gliotoxin (1), 12,13-dihydroxy-fumitremorgin C (2), fumitremorgin (3), bisdethiobis(methylthio)gliotoxin (4), demethoxyfumitremorgin C (5), vermistatin (6), cyclo-(L-Trp-L-Pro) (7), 6-methoxyspirotryprostatin B (8), and citrinolactone D (9). Conclusion Nine compounds were isolated for the first time from co-culture of the fungus Alternaria alternata YX-25 and Streptomyces exfoliates YX-32, including indole diketopiperazines, polyketides, and cyclopeptides. The co-cultivation method can be as a new method for enrichment of secondary metabolites.

Gliotoxin is Antibacterial to Drug-resistant Piscine Pathogens

By activity-guided fractionation, gliotoxin was isolated as an antibacterial metabolite of the fungus Penicillium decumbens which was derived from the jellyfish Nemopilema nomurai. Gliotoxin was further evaluated for antibacterial activity against several piscine and human MDR (multidrug resistance) pathogens. Gliotoxin showed significant antibacterial activity against Gram-positive piscine pathogens such as Streptococcus iniae FP5228, Streptococcus iniae FP3187, Streptococcus parauberis FP3287, Streptococcus parauberis SPOF3K, S. parauberis KSP28, and Lactococcus garvieae FP5245. Gliotoxin showed strong activity especially against S. parauberis SPOF3K and S. iniae FP5228, which are resistant to oxytetracycline. It is noteworthy that gliotoxin effectively suppressed streptococci which are the major pathogens for piscine infection and mortality in aquaculture industry. Gliotoxin also showed strong antibacterial activity against multidrug-resistant human pathogens (MDR) including Enterococcus faecium 5270 and MRSA (methicillin-resistant Staphylococcus aureus) 3089.

Curcumin decreases astrocytic reaction after gliotoxic injury in the rat brainstem / Curcumina reduz a reação astrocitária após injúria gliotóxica no tronco encefálico de ratos

ABSTRACT Recent studies have demonstrated that curcumin (Cur) has antioxidant, anti-inflammatory and anti-fibrotic effects. Ethidium bromide (EB) injections into the central nervous system (CNS) are known to induce local oligodendroglial and astrocytic loss, resulting in primary demyelination and neuroinflammation. Peripheral astrogliosis is seen around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP). This investigation aimed to evaluate the effect of Cur administration on astrocytic response following gliotoxic injury. Wistar rats were injected with EB into the cisterna pontis and treated, or not, with Cur (100 mg/kg/day, intraperitoneal route) during the experimental period. Brainstem sections were collected at 15, 21 and 31 days after EB injection and processed for GFAP immunohistochemical staining. Astrocytic reactivity was measured in a computerized system for image analysis. In Cur-treated rats, the GFAP-stained area around the lesion was significantly smaller in all periods after EB injection compared to untreated animals, showing that Cur reduces glial scar development following injury.

RESUMO Estudos recentes têm demonstrado que a curcumina (Cur) possui efeitos antioxidantes, anti-inflamatórios e antifibróticos. Sabe-se que a injeção de brometo de etídio (EB) no sistema nervoso central induz a perda oligodendroglial e astrocitária, resultando em desmielinização primária e neuroinflamação. Astrogliose periférica é observada ao redor da lesão com aumento da imunorreatividade à proteína glial fibrilar ácida (GFAP). A presente investigação objetivou avaliar o efeito da Cur sobre a resposta astrocitária após injúria gliotóxica. Ratos Wistar foram injetados com EB na cisterna basal e tratados ou não com Cur (100 mg/kg/dia, via intraperitoneal) durante o período experimental. Amostras do tronco encefálico foram coletadas aos 15, 21 e 31 dias pós-injeção de EB e processadas para estudo imuno-histoquímico para a GFAP. A reatividade astrocitária foi medida em um sistema computadorizado para análise de imagem. Nos ratos tratados com Cur, a área marcada para GFAP foi significantemente menor em todos os períodos pós-injeção de EB, indicando que a Cur reduz o desenvolvimento da cicatriz glial após injúria.

Propentofylline reduces glial scar development following gliotoxic damage in the rat brainstem / Propentofilina reduz o desenvolvimento da cicatriz glial após dano gliotóxico no tronco encefálico de ratos

ABSTRACT Propentofylline is a xanthine derivative that depresses activation of glial cells, whose responses contribute to neural tissue damage during inflammation. Ethidium bromide injection into the central nervous system induces local oligodendroglial and astrocytic loss, resulting in primary demyelination, neuroinflammation and blood-brain barrier disruption. Surviving astrocytes present a vigorous reaction around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP). Objective This study aimed to evaluate the effect of propentofylline administration on astrocytic response following gliotoxic injury. Method Wistar rats were injected with ethidium bromide into the cisterna pontis and treated or not with propentofylline (12.5mg/kg/day, intraperitoneal) during the experimental period. Brainstem sections were collected from 15 to 31 days after gliotoxic injection and processed for GFAP immunohistochemistry. Results and Conclusion Results demonstrate that propentofylline decreased astrocytic activation until the 21st day, suggesting that this drug may have a role in reducing glial scar development following injury.

RESUMO A propentofilina é uma xantina que deprime a ativação das células gliais, cujas respostas contribuem para o dano neural durante inflamação. A injeção de brometo de etídio no sistema nervoso central induz a perda oligodendroglial e astrocitária, resultando em desmielinização, neuroinflamação e ruptura da barreira hematoencefálica. Os astrócitos sobreviventes apresentam vigorosa reação ao redor da lesão com aumento da imunorreatividade à proteína glial fibrilar ácida (GFAP). Objetivo Este estudo objetivou avaliar o efeito da propentofilina sobre a resposta astrocitária após injúria gliotóxica. Método Ratos Wistar foram injetados com brometo de etídio na cisterna basal e tratados ou não com propentofilina (12.5mg/kg/dia, intraperitoneal). Amostras do tronco encefálico foram coletadas dos 15 aos 31 dias pós-injeção do gliotóxico e processadas para estudo ultraestrutural e imuno-histoquímico para GFAP. Resultados e Conclusão Os resultados demonstram que a propentofilina reduziu a ativação astrocitária até o 21o dia, sugerindo que essa droga pode atuar na redução da cicatriz glial após injúria.

Gliotoxin enhances antitumor activity of endoplasmic reticulum stress inducer-tunicamycin / 中国药学杂志

OBJECTIVE: To investigate whether the proteasome inhibitor, gliotoxin, combined with the endoplasmic reticulum stress inducer, tunicamycin, could enhance the apoptotic death of tumor cells. METHODS: MTT assay was used to detect the cytotoxicity. The combined drug index (CDI) was used to evaluate the synergistic effect. Flow cytometry was used to analyze the apoptosis rate. The protein expression level was detected by Western blot. RESULTS: The IC50 of gliotoxin and tunicamycin is (1.44±0.23) and (26.14±6.14) μmol·L-1, respectively. In the effective concentration, gliotoxin combined with tunicamycin could significantly inhibit cell proliferation and induce typical apoptotic morphological changes. The combination was synergistic according to the result of MTT assay. As measured by flow cytometry, the combination remarkably increased the apoptosis rates of HT-1080 cells, especially for 0.2 μmol·L-1 gliotoxin combined with tunicamycin, the apoptosis rate was up to 66.6% and CDI was 0.649. The expression changes of apoptosis-related proteins such as caspase-8, caspase-3, PARP and NF-kB were detected when treated with the combination. CONCLUSION: Gliotoxin can improve the chemosensitivity of fibrosarcoma HT-1080 cells to tunicamycin and enhance the apoptosis of tumor cells induced by tunicamycin. Thus, our study may provide a new drug combination to antitumor therapy.

Regulation of Development in Aspergillus nidulans and Aspergillus fumigatus

Members of the genus Aspergillus are the most common fungi and all reproduce asexually by forming long chains of conidiospores (or conidia). The impact of various Aspergillus species on humans ranges from beneficial to harmful. For example, several species including Aspergillus oryzae and Aspergillus niger are used in industry for enzyme production and food processing. In contrast, Aspergillus flavus produce the most potent naturally present carcinogen aflatoxins, which contaminate various plant- and animal-based foods. Importantly, the opportunistic human pathogen Aspergillus fumigatus has become the most prevalent airborne fungal pathogen in developed countries, causing invasive aspergillosis in immunocompromised patients with a high mortality rate. A. fumigatus produces a massive number of small hydrophobic conidia as the primary means of dispersal, survival, genome-protection, and infecting hosts. Large-scale genome-wide expression studies can now be conducted due to completion of A. fumigatus genome sequencing. However, genomics becomes more powerful and informative when combined with genetics. We have been investigating the mechanisms underlying the regulation of asexual development (conidiation) and gliotoxin biosynthesis in A. fumigatus, primarily focusing on a characterization of key developmental regulators identified in the model fungus Aspergillus nidulans. In this review, I will summarize our current understanding of how conidiation in two aspergilli is regulated.

Prevalência de aspergilose broncopulmonar alérgica em pacientes com fibrose cística na Bahia, Brasil / Prevalence of allergic bronchopulmonary aspergillosis in patients with cystic fibrosis in the state of Bahia, Brazil

OBJETIVO: Determinar a prevalência de aspergilose broncopulmonar alérgica (ABPA) em pacientes com fibrose cística acompanhados em um centro de referência da Bahia. MÉTODOS: Estudo transversal, com coleta prospectiva de dados, realizado no Centro de Referência de Fibrose Cística da Bahia do Hospital Especializado Octavio Mangabeira. Foram incluídos no estudo 74 pacientes que tinham diagnóstico de fibrose cística, com idade acima de 6 anos e tratados entre 9 de dezembro de 2003 e 7 de março de 2005. Foram analisadas as seguintes variáveis: gênero, idade, capacidade vital forçada, volume expiratório forçado no primeiro segundo, resposta a prova farmacodinâmica, achados em radiografia torácica e de seios de face, presença de sibilância, culturas para Aspergillus spp., imunoglobulina E (IgE) total, IgE específica para Aspergillus fumigatus e teste cutâneo de leitura imediata para aspergilina. RESULTADOS: Dos 74 pacientes, 2 foram diagnosticados com ABPA. Níveis de IgE total > 1.000 UI/mL foram observados em 17 pacientes (23%), teste cutâneo de leitura imediata para A. fumigatus positivos em 19 (25,7%) e sibilância em 60 (81,1%). CONCLUSÕES: A taxa de prevalência de ABPA foi de 2,7%. As altas taxas de IgE total, de teste cutâneo imediato para A. fumigatus positivos e de sibilância sugerem que estes pacientes devam ser acompanhados cuidadosamente por haver a possibilidade do desenvolvimento de ABPA.

OBJECTIVE: To determine the prevalence of allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis treated at a referral center in the state of Bahia, Brazil. METHODS: A cross-sectional study, with prospective data collection, carried out at the Cystic Fibrosis Referral Center of Bahia of the Octavio Mangabeira Specialized Hospital. We evaluated 74 patients diagnosed with cystic fibrosis, older than six years of age, treated between December 9, 2003 and March 7, 2005. We analyzed the following variables: gender, age, forced vital capacity, forced expiratory volume in one second, pharmacodynamic response, chest X-ray findings, facial sinus X-ray findings, wheezing, cultures for Aspergillus spp., total immunoglobulin E (IgE), specific IgE for Aspergillus fumigatus and immediate skin test reactivity to A.fumigatus antigen. RESULTS: Of the 74 patients, 2 were diagnosed with ABPA. We found total IgE levels > 1,000 IU/mL in 17 (23%), positive immediate skin reactivity to A. fumigatus antigen in 19 (25.7%) and wheezing in 60 (81.1%). CONCLUSIONS: The prevalence of ABPA was 2.7%. The high levels of total IgE, high incidence of wheezing and high rate of immediate skin test reactivity to A. fumigatus antigen suggest that these patients should be carefully monitored due to their propensity to develop ABPA.

Control of root-rot diseases of Phaseolus vulgaris using gliotoxin

Effect of the antifungal antibiotic gliotoxin on root-rot diseases caused by Fusarium solani and its influence on population of fungal flora in soil were investigated. Bean seeds were treated with different concentrations of gliotoxin before sowing. The results obtained from the green house application of bioagent indicated that soaking seeds in different concentrations of gliotoxin from 1μg/mL to 15μg/mL (for 60 minutes) significantly reduced the percentage of damping off and root rot as compared with control (pathogen only). Also 10μg/mL of gliotoxin was significantly decreased the population of fungal flora as compared with control.

Study on the Interaction of Gliotoxin with BSA / 微生物学通报

The interaction between Gliotoxin and bovine serum albumin (BSA) was studied by the fluo-rescence, Circular Dichroism (CD) and ultraviolet visible (UV-Vis) techniques. The fluorescent experiment showed that the intrinsic fluorescence of BSA was quenched by the binding of gliotoxin in a static quenching procedure, with an association constant of 7.2?103 L/mol and in hydropobic forces. And the CD spectrum revealed that gliotoxin effected the conformation of BSA by increased the mass of ?-helix.

Gliotoxin Protects Against TNBS-induced Colitis Via Down-regulation of NF B Activation / 대한해부학회지

During inflammation of the colon, cells of the gut mucosa express numerous inflammatory mediators including interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta(IL-1beta). These cytokines have been implicated as contributing factors in the inflammatory process, which may result in colitis during inflammatory bowel disease (IBD). Gliotoxin is a fungal metabolite of an epipolythiodioxopiperazine analogue with immunosup-pressive properties in vivo and in vitro, but the effects of gliotoxin on IBD have not been largely evaluated. Therefore, this study evaluated the potential of gliotoxin to protect against TNBS-induced colitis. One microgram of gliotoxin in 100microliter of vehicle was intra-rectally administered into mice exhibiting trinitrobenzene sulfonic acid (TNBS)-induced colitis. IL-8 secretion was measured using an enzyme-linked immu-nosorbent assay (ELISA), myeloperoxidase (MPO) activity was evaluated spectrophotometically, and IkappaB degradation was analyzed on Western blots. Gliotoxin treatment of mice bearing TNBS-induced colitis improved macro-and micro-pathological findings and dramatically decreased MPO activity, a marker of leukocyte infiltration. Furthermore, gliotoxin decreased IkappaB degradation and IL-8 induction caused by TNF-alpha or IL-1beta in HT-29 cells. These findings suggest that gliotoxin partially protects against TNBS-induced colitis through the sup-pression of IL-8 induction and IkappaB degradation by inflammatory mediators such as TNF-alpha or IL-1beta.

Protective Effect of PKC Affecting Gliotoxin-induced Cytotoxicity in Rat Smooth Muscle Cells / 대한해부학회지

Aspergillus funigatus and other pathogenic fungi synthesize a toxic epidithi-odiopiperzine (ETP) metabolite, namely gliotoxin. Gliotoxin commonly react with sulfhydryl groups, and then, forms hydrogen peroxide. These fungal toxins induce apoptotic cell death in various cells. Apoptosis induced by gliotoxin need calcium. Effect of calcium preconditioning was not reported in gliotoxin-induced apoptosis. To examine the effect of protein kinase C (PKC) and calcium which was regulate caspase-3, PKC and calcium preconditioning before gliotoxin treatment, apoptotic agents such as bcl-2 family, caspase-3 and DNA fragmentation in A7r5 cell line from rat smooth muscle cell were studied. These results showed that gliotoxin induces the expression of bad of bcl-2 family, caspase-3 activation and DNA fragmentation in A7r5 cells. Gliotoxin treatment followed by calcium and PKC preconditioning suppress the Bad of bcl-2 family, and inhibited caspase-3 activation, respectively. These results suggest that PKC and calcium preconditioning protect the gliotoxin-induced apoptosis, through the protection of pro-apoptotic bcl-2 family in A7r5 cells.

The Effect of Protein Kinase C Pretreatment on Gliotoxin Induced Apoptosis in H9c2 Cells / 체질인류학회지

Aspergillus funigatus and other pathogenic fungi synthesize a toxic epidithi- odiopiperzine (ETP) metabolite called gliotoxin. Gliotoxin is an epidithiodiopiperzine compound which can both react with sulfhydryl groups and form hydrogen peroxide. The fungal toxin gliotoxin induces apoptotic cell death in a variety of cells. Apoptosis induced by gliotoxin need calcium but effect of calcium preconditioning is unknown by gliotoxin. We studied the effect of protein kinase C and calcium preconditioning on gliotoxin-induced apoptosis in H9c2 cell. PKC and calcium preconditiong inhibited DNA fragmentation by gliotoxin. From this above results suggest that gliotoxin induce apoptosis via caspase-3 activation, because caspase-3 inhibitor (DEVD-CHO) didn't induce apoptosis in gliotoxin treated H9c2 clls. Calcium and PKC preconditioning inhibit caspase-3 activation by gliotoxin. These data means that PKC preconditioning is related with caspase-3 regulate in gliotoxin-induced apoptosis.

The Protective Mechanism of Zinc in Fungal Metabolte Gliotoxin - induced Apoptosis

Gliotoxin, a fungal metabolite, is one of the epipolythiodioxopiperazine classes and has a variety of effects including imrnunomodulatory and apoptotic agents. This study is designed to evaluate the effect of zinc on gliotoxin-induced death of HL-60 cells. Here, we demonstrated that treatment of gliotoxin decreased cell viability in a dose and time-dependent manner. Gliotoxin-induced cell death was confirtned as apoptosis characterized by chromatin marginafion, fragmentation and ladder-pattern digestion of genomic DNA. Gliotoxin increased the proteolytic activities of caspase 3, 6, 8, and 9. Caspase-3 activation was further confirmed by the degradation of procaspase-3 and PARP in gliotoxin-treated HL-60 cells. Zinc compounds including ZnC12 and ZnSO4 markedly inhibited gliotoxin-induced apoptosis in HL-60 cells (from 30% to 90%). Consistent with anti- apoptotic effects, zinc also suppressed the enzymatic activities of caspase-3 and -9 proteases. In addition, cleavage of both PARP and procaspase 3 in gliotoxin-treated HL-60 cells was inhibited by the addition of zinc compounds. We further demonstrated that expression of Fas ligand by gliotoxin was suppressed by zinc compounds. These data suggest that zinc may prevent gliotoxin- induced apoptosis via inhibition of Fas ligand expression as well as suppression of caspase family cysteine proteases-3 and -9 in HL-60 cells.

Gliotoxin induces the Apoptosis in HL-60 Cells / 대한면역학회지

Many fungi including Penicillium, Aspergillus, Gliocladium, and Thermoascus produce an epipolythiodioxopiperazine class of fungal metabolite, gliotoxin, which contirbutes the pathogenesis of fungal infection as an immunomodulator and cytotoxic agent. This study is designed to define the mechanism by which gliotoxin exerts the cytotoxic effect of gliotoxin on human promyelocytic leukemic cells, HL-60. Gliotoxin induces the apoptosis of HL-60 cells which is characterized by the ladder pattern fragmentation of DNA. Gliotoxin induces the activation of DEVD-specific cysteine protease in a time- and dose-dependent rnanner. It also increases the phosphotransferase activities of c-Jun N-terminal kinase1 (JNK1) and p38 in gliotoxin-treated HL-60 cells. Furthermore, gliotoxin decreases the activation of transcriptional activator, actiating protein (AP-1) and NF-kB. These results suggest that gliotoxin induces the apoptotic death of HL-60 cells via activation of DEVD- specific caspase as well as mitogen activated protein kinases (MAP kinases) including JNK1 and p38, and inhibition of transcriptional activators, AP-1 and NF-kB.