RESUMEN
Peripheral blood mononuclear cells (PBMC), sourced autologously, offer numerous advantages when procured: easier acquisition process, no in vitro amplification needed, decreased intervention and overall increased acceptability make PBMC an attractive candidate for cell therapy treatment. However, the exact mechanism by which PBMC treat diseases remains poorly understood. Immune imbalance is the pathological basis of many diseases, with macrophages playing a crucial role in this process. However, research on the role and mechanisms of PBMC in regulating macrophages remains scarce. This study employed an in vitro co-culture model of PBMC and RAW264.7 macrophages to explore the role and mechanisms of PBMC in regulating macrophages. The results showed that the co-culturing led to decreased expression of inflammatory cytokines and increased expression of anti-inflammatory cytokines in RAW264.7 or in the culture supernatant. Additionally, the pro-inflammatory, tissue matrix-degrading M1 macrophages decreased, while the anti-inflammatory, matrix-synthesizing, regenerative M2 macrophages increased in both RAW264.7 and monocytes within PBMC. Moreover, co-cultured macrophages exhibited a significantly decreased p-STAT1/STAT1 ratio, while the p-STAT6/STAT6 ratio significantly increased. This suggests that PBMC may inhibit M1 macrophage polarization by blocking STAT1 signaling cascades and may promote M2 macrophage polarization through the activation of STAT6 signaling cascades. Overall, this study sheds light on the role and mechanism of PBMC in regulating macrophages. Moreover, it was found that monocytes within co-cultured PBMC differentiated into M2 macrophages in the presence of macrophages. This finding provides experimental evidence for the use of PBMC in treating inflammatory diseases, especially macrophage-depleting inflammatory diseases such as osteoarthritis.
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Técnicas de Cocultivo , Leucocitos Mononucleares , Macrófagos , Factor de Transcripción STAT1 , Factor de Transcripción STAT6 , Transducción de Señal , Animales , Ratones , Citocinas/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Activación de Macrófagos , Macrófagos/inmunología , Macrófagos/metabolismo , Células RAW 264.7 , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT6/metabolismoRESUMEN
The majority of blood malignancies is incurable and has unforeseeable remitting-relapsing paths in response to different treatments. Cynaropicrin, a natural sesquiterpene lactone from the edible parts of the artichoke plant, has gained increased attention as a chemotherapeutic agent. In this study, we investigated the effects of cynaropicrin against multiple myeloma (MM) cells in vitro and assessed its in vivo effectiveness in a xenograft tumor zebrafish model. We showed that cynaropicrin exerted potent cytotoxicity against a panel of nine MM cell lines and two leukemia cell lines with AMO1 being the most sensitive cell line (IC50 = 1.8 ± 0.3 µM). Cynaropicrin (0.8, 1.9, 3.6 µM) dose-dependently reduced c-Myc expression and transcriptional activity in AMO1 cells that was associated with significant downregulation of STAT3, AKT, and ERK1/2. Cell cycle analysis showed that cynaropicrin treatment arrested AMO1 cells in the G2M phase along with an increase in the sub-G0G1 phase after 24 h. With prolonged treatment times, cells accumulated more in the sub-G0G1 phase, implying cell death. Using confocal microscopy, we revealed that cynaropicrin disrupted the microtubule network in U2OS cells stably expressing α-tubulin-GFP. Furthermore, we revealed that cynaropicrin promoted DNA damage in AMO1 cells leading to PAR polymer production by PARP1 hyperactivation, resulting in AIF translocation from the mitochondria to the nucleus and subsequently to a novel form of cell death, parthanatos. Finally, we demonstrated that cynaropicrin (5, 10 µM) significantly reduced tumor growth in a T-cell acute lymphoblastic leukemia (T-ALL) xenograft zebrafish model. Taken together, these results demonstrate that cynaropicrin causes potent inhibition of hematopoietic tumor cells in vitro and in vivo.
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Mieloma Múltiple , Parthanatos , Sesquiterpenos , Animales , Humanos , Tubulina (Proteína) , Pez Cebra/metabolismo , Mieloma Múltiple/tratamiento farmacológico , Lactonas/farmacología , Lactonas/uso terapéutico , Sesquiterpenos/farmacología , Sesquiterpenos/uso terapéutico , Línea Celular TumoralRESUMEN
OBJECTIVE: Gastrointestinal dysfunction seriously affects the prognosis and quality of life of patients with multiple fractures. However, experimental evidence of this relationship is lacking. Here we describe a newly developed mouse model of postoperative gastrointestinal dysfunction after multiple fractures. METHODS: Trauma severity was assessed using the injury severity score (ISS). Based on the ISS, a multiple fracture model was established in mice as follows: limb fractures with pelvic fractures and multiple rib fractures; limb fractures with multiple rib fractures; closed fracture of both forelegs with pelvic fracture and rib fractures; closed limb fractures; limb fracture with pelvic fracture; spinal fractures; hind leg fractures with pelvic fractures; pelvic fracture with multiple rib fractures; closed fracture of both fore legs with pelvic fracture; and closed fracture of both fore legs with multiple rib fractures. In each model group, gastrointestinal motility was assayed and the histopathology of the small intestine was examined. Western blot and immunohistochemical analyses of jejunal tissue were performed to detect c-kit protein expression, the level of which was compared with that of a control group. The results of ANOVA are expressed as mean ± standard deviation. RESULTS: In mice with multiple fractures, food intake was greatly reduced, consistent with histopathological evidence of an injured intestinal epithelium. The jejunal tissue of mice in groups a, c, f, and h was characterized by extensively necrotic and exfoliated intestinal mucosal epithelium and inflammatory cell infiltration in the lamina propria. In the gastrointestinal function assay, gastrointestinal motility was significantly reduced in groups a, b, c, f, and g; these group also had a higher ISS (p < 0.01). The expression of c-kit protein in groups with gastrointestinal dysfunction was significantly up-regulated (p < 0.001) compared with the control group. The close correlation between c-kit expression and the ISS indicated an influence of trauma severity on gastrointestinal motility. CONCLUSION: Gastrointestinal dysfunction after multiple fractures was successfully reproduced in a mouse model. In these mice, c-kit expression correlated with gastrointestinal tissue dysfunction and might serve as a therapeutic target.
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Fracturas Óseas , Fracturas Cerradas , Fracturas Múltiples , Células Intersticiales de Cajal , Traumatismo Múltiple , Huesos Pélvicos , Fracturas de las Costillas , Fracturas de la Columna Vertebral , Ratones , Animales , Puntaje de Gravedad del Traumatismo , Proteínas Proto-Oncogénicas c-kit , Calidad de Vida , Huesos Pélvicos/lesiones , Estudios RetrospectivosRESUMEN
OBJECTIVE: To evaluate toxicity of raw extract of Panax notoginseng (rPN) and decocted extract of PN (dPN) by a toxicological assay using zebrafish larvae, and explore the mechanism by RNA sequencing assay. METHODS: Zebrafish larvae was used to evaluate acute toxicity of PN in two forms: rPN and dPN. Three doses (0.5, 1.5, and 5.0 µ g/mL) of dPN were used to treat zebrafishes for evaluating the developmental toxicity. Behavior abnormalities, body weight, body length and number of vertebral roots were used as specific phenotypic endpoints. RNA sequencing (RNA-seq) assay was applied to clarify the mechanism of acute toxicity, followed by real time PCR (qPCR) for verification. High performance liquid chromatography analysis was performed to determine the chemoprofile of this herb. RESULTS: The acute toxicity result showed that rPN exerted higher acute toxicity than dPN in inducing death of larval zebrafishes (P<0.01). After daily oral intake for 21 days, dPN at doses of 0.5, 1.5 and 5.0 µ g/mL decreased the body weight, body length, and vertebral number of larval zebrafishes, indicating developmental toxicity of dPN. No other adverse outcome was observed during the experimental period. RNA-seq data revealed 38 genes differentially expressed in dPN-treated zebrafishes, of which carboxypeptidase A1 (cpa1) and opioid growth factor receptor-like 2 (ogfrl2) were identified as functional genes in regulating body development of zebrafishes. qPCR data showed that dPN significantly down-regulated the mRNA expressions of cpa1 and ogfrl2 (both P<0.01), verifying cpa1 and ogfrl2 as target genes for dPN. CONCLUSION: This report uncovers the developmental toxicity of dPN, suggesting potential risk of its clinical application in children.
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Panax notoginseng , Saponinas , Animales , Pez Cebra/genética , Saponinas/farmacología , Panax notoginseng/química , Larva , Análisis de Secuencia de ARNRESUMEN
Zebrafish of different strains with 5 dpf (5 days post-fertilization) were selected and fed with 0.2% high-fat diet for 8 h and 3% glucose solution for 16 halternatively during the day and night for 4 consecutive days. The zebrafish model was established and randomly divided into model group, Huangdi Anxiao Capsules (260 mg·L⻹) group and pioglitazone (32 mg·L⻹) group. The drug treatment groups were given the water-soluble drugs, with a volume of 25 mL, and incubated in a 28 °C incubator for 4 days. To detect the exposure to the corresponding drugs, the normal control group was set up. Thirty zebrafish were included in each group. The effect of Huangdi Anxiao Capsules on vascular wall thickness, fluorescence intensity of islet beta cells, fluorescence intensity of macrophages, and blood flow velocity of zebrafish were detected. The expressions of vascular endothelial growth factor (vegfaa) and angiotensin converting enzyme (ACE) were detected by RT-PCR. The results showed that compared with the model group, Huangdi Anxiao Capsules can significantly reduce the thickness of the blood vessel wall, increase the fluorescence intensity of islet ß cells and macrophages, increase the blood flow velocity in vivo, and decrease the ACE and vegfaa expressions in zebrafish. It is suggested that Huangdi Anxiao Capsules may alleviate zebrafish vascular lesions by regulating the expressions of ACE and vegfaa.
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Medicamentos Herbarios Chinos/farmacología , Enfermedades Vasculares/tratamiento farmacológico , Pez Cebra , Animales , Cápsulas , Dieta Alta en Grasa/efectos adversos , Glucosa/efectos adversos , Peptidil-Dipeptidasa A/metabolismo , Distribución Aleatoria , Enfermedades Vasculares/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Proteínas de Pez Cebra/metabolismoRESUMEN
The aim of this study is to use zebrafish embryos as a quick platform for wound healing studies. At beginning, we optimized a protocol to induce skin lesion by acetic acid injection. The acetic acid injection induced regional inflammation wound hyperpigmentation by recruiting pigment cells to the wound area. Later, we applied established platform to evaluate the effect of tilapia's collagen peptide mixtures, including demonstration on promoting skin wound healing and eliminating inflammatory response. Results showed that after treating TY001, one of the above fish collagen peptide mixtures, not only repair and proliferation were induced, but also death and apoptosis cells were cleared within cutaneous lesion. Moreover, inflammatory response was suppressed along with collagen mixture treatment. Finally, the TY001-associated signaling was validated by real time-PCR, and numbers of gene associated with tissue repair and vessel proliferation were induced. To sum up, our findings provided a permissive model that may apply to generate a platform for further screening on repair and restoration technology. In addition, the tilapia fish collagen peptide mixture we applied on our model has great potential on developing clinical application on wound healing.
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Colágeno/uso terapéutico , Cicatrización de Heridas/efectos de los fármacos , Ácido Acético/toxicidad , Animales , Apoptosis , Proliferación Celular , Piel/citología , Piel/efectos de los fármacos , Pez Cebra/embriologíaRESUMEN
Epimedin C is one of the chemical markers and major flavonoids in Herba Epimedii (Yinyanghuo), which is traditionally used to treat bone diseases and gonadal dysfunction in China. Our previous study indicated that epimedin C could induce endothelial-like, but not osteogenic differentiation of C3H/10T1/2 cells in vitro. As vasculogenesis plays a pivotal role in bone formation, this study used the bone morphogenetic protein 2 (BMP2) induced ectopic bone formation model and mice 4T1 breast cancer cells co-implanted with luciferase labeled C3H/10T1/2 cells (4T1 [Formula: see text] C3H/10T1/2-Luc) model to examine the in vivo effects of Epimedin C on vasculogenesis. As a result, Epimedin C significantly increased the bone weight and blood perfusion of mice in the BMP2 induced ectopic osteogenesis model, and the bone in Epimedin C [Formula: see text] BMP2 group was more mature than that in BMP2 group. In addition, the tumor weight, blood perfusion and tumor-associated angiogenesis were also significantly increased in the Epimedin C treated 4T1 tumor bearing mice. The mRNA levels of endothelial markers, such as the platelet endothelial adhesive factor-1(CD31), the endothelial cell specific molecule-1(ESM-1), and the vascular von Willebrand factor (vWF) in mouse 4T1 mammary tumor tissue, were commonly found to occur alongside the luciferase (labeled in C3H/10T1/2 cells) expression and significantly increased after Epimedin C treatment. Taken together, Epimedin C can effectively promote vascularization both in the BMP2-depended bone formation model and in the 4T1 mammary tumor-bearing model by inducing an endothelial-like differentiation of C3H/10T1/2 in BALB/c nude mice.
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Proteína Morfogenética Ósea 2 , Diferenciación Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Células Endoteliales/citología , Flavonoides/farmacología , Neoplasias Mamarias Experimentales/irrigación sanguínea , Neovascularización Patológica , Osificación Heterotópica , Osteogénesis/efectos de los fármacos , Animales , Línea Celular , Línea Celular Tumoral , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Flavonoides/aislamiento & purificación , Flavonoides/uso terapéutico , Ratones Endogámicos BALB C , Ratones Desnudos , FitoterapiaRESUMEN
OBJECTIVE: To observe application value of multispectral animal living imaging technology in rats model of osteoarthritis. METHODS: Fifteen male SD rats weighed (180 +/- 20) g (3 months old) were received intra-articular injection of iodoacetic acid for establishing osteoarthritis. Articular cavity of left knee of rats were injected into 50 microl iodoacetic acid. The same volume of sterile saline was injected into right knee articular cavity as control. X-ray living imaging and bone mineral density were observed at 2 and 4 weeks after establishment of model. After 4 weeks,rats were sacrificed and their bilateral joints were collected and determined histologically based on Collins classification and Kellgren-Lawrence classification. RESULTS: Osteoarthritis model was successfully established, compared with control group, model group showed typical manifestation of osteoarthritis, including irregular cartilage surface,osteophyte formation,joint deformity and cartilage defect,and combined with significant decrease of bone density (P < 0.01), while the decrease was not obvious in proximal tibia (P < 0.05). After 2 weeks, knee joints in model group was classified as Collins grade 1 and Kellgren-Lawrence grade 2,then classified as Collins grade 4 and Kellgren-Lawrence grade 3 after 4 weeks,control group showed smooth articular surface,normal joint space and intact cartilage surface, knee joints was classified as Collins and Kellgren-Lawrence grade 0, and bone density of distal femur and proximal tibia were normal. CONCLUSION: Multispectral animal living imaging technology could be used in dynamic observation of living imaging and detection of bone density in the animal model of osteoarthritis, and it is significant for evaluation of osteoarthritis model, and its realted tesearch.
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Osteoartritis/diagnóstico por imagen , Animales , Densidad Ósea , Modelos Animales de Enfermedad , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Osteoartritis/diagnóstico , Osteoartritis/fisiopatología , Radiografía , Ratas , Ratas Sprague-DawleyRESUMEN
OBJECTIVE: To compare biological characteristics between nucleus pulposus and annulus fibrosus cells in vitro model. METHODS: Five New Zealand white rabbits (2 to 3 kg, either gender) were isolated nucleus pulposus and annulus fibrosus under sterilized condition, then cultured in nutrient solution with 15% FBS and DMEM/F12 (1:1) by enzyme digestion combined with tissue block method. When 90% cells fused, subcultring were performed. Cell morphology were observed by inverted phase contrast microscope, cell viability were detected by trypan blue staining, histological were observed by a toluidine blue and HE staining, cell proliferation were tested by MTT method, then the cell morphology, viability, proliferation between nucleus pulposus and annulus fibrosus were compared. RESULTS: There were no obviously differences between nucleus pulposus and annulus fibrosus in original and the first strain. Physalides were appeared in annulus fibrosus on the second generation. The strapping time was later, and activity was lower in nucleus pulposus than annulus fibrosus. The growth of cell proliferation in nucleus pulposus was lower than annulus fibrosus from the ninth day. CONCLUSION: The cell activity in annulus fibrosus is higher than nucleus pulposus. Digenerative disc disease may caused by recession of nucleus pulposus,local biomechnical changes, furether caused structure change and function loss of annulus fibrosus.
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Degeneración del Disco Intervertebral/fisiopatología , Disco Intervertebral/citología , Animales , Proliferación Celular , Supervivencia Celular , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , ConejosRESUMEN
OBJECTIVE: To study the effect of H2O2 on the morphological pattern,vitality,proliferation,cycle period of rabbit intervertebral disc nucleus pulposus cells. METHODS: Ten New Zealand white rabbits (2 to 3 kg, female) were used for isolating nucleus pulposus cells under sterilized condition. The culture solution with 15% FBS and DMEM/F12 (1:1) was applied for cell cultivation. After 90% cell fusion, the first generation was obtain and stimulated by H2O2 with different concentrations of 0 micromol/L (control group), 130 micromol/L,216 p.mol/L,360 Ipmol/L, 600 micromol/L,and 1000 micromol/L. RESULTS: Compared with the control group, there was little difference of the biological property (P>0.05) in 130 micromol/L and 216 micromol/L H202-treated groups. When the concentration of H2O2 attained 360 micromol/L, 600 micromol/L, and 1 000 micromol/L, the cells suffered aging,with increased cell vacuoles,decreased proliferation,and aging:related increase of 13-galactosidase dyeing. The cell cycle of many nucleus pulposus cells was blocked in G1 stage other than entering S stage. With increasing H2O2 concentrations, the aging degree was increased. CONCLUSION: A certain concentration of H202 could induce early aging of nucleus pulposus cells,resulting in biological abnormalities of these cells.
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Senescencia Celular/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Disco Intervertebral/efectos de los fármacos , Estrés Oxidativo , Animales , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Femenino , Disco Intervertebral/citología , ConejosRESUMEN
The endophytic bacterium, MD-b1, was isolated from the medicinal plant Ophiopogon japonicas and identified as the Bacillus amyloliquefaciens sp. with 99% similarity based on the partial sequence analysis of 16S rDNA. Exopolysaccharides were extracted from the endophyte for the evaluation of its antitumor activity against gastric carcinoma cell lines (MC-4 and SGC-7901). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and microscopy were performed to estimate the cell viability and morphological changes of the MC-4 and SGC-7901 cells following treatment with the exopolysaccharides at 14, 22 and 30 µg/µl. The results revealed that the exopolysaccharides displayed concentration-dependent inhibitory effects against the MC-4 and SGC-7901 cells, with an IC50 of 19.7 and 26.8 µg/µl, respectively. The exopolysaccharides also induced morphological abnormalities in the cells. These effects indicated the the exopolysaccharides had an antitumoral mechanism of action associated with the mitochondrial dysfunction of the treated cells. This is the first study to investigate the endophytic microorganism isolated from O. japonicas and also the first discovery of such antitumoral exopolysaccharides derived from the genus Bacillus. This provides a promising and reproducible natural product source with high therapeutic value for anticancer treatment, thereby facilitating the development of new anticancer agents.
RESUMEN
Appearance of proteomics technology can fleetly filt and reveal specificity biomarkers of disease, this will help to reveal the pathogenesis of femur head necrosis and help early diagnosis, find more effective methods and therapeutic targets. At present, they are hot spots that find out the occurred mechanism,related proteins of early diagnosis and early treatment and its functional identification; set up the early related database; optimize the protein extraction methods for research of femur head necrosis. This article reviews the application of study technology of related proteins of femur head necrosis on bone tissue, serum,related animal model,and in order to provide further research ideas.
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Necrosis de la Cabeza Femoral/metabolismo , Proteómica/métodos , Diagnóstico Precoz , Necrosis de la Cabeza Femoral/diagnóstico , HumanosRESUMEN
OBJECTIVE: To explore the effect of Yougui Recipe, a kidney-supplementing and yang-activating formula which on the behavioral changes of rat of steroid-induced avascular necrosis of the femoral head (SANFH). METHODS: Thirty Wistar rats were involved and were randomly divided into the blank control group (group A), the model group (group B) and the Yougui Recipe group (group C). SANFH models were established by injection of colibacillus endotoxin and prednisolone intramuscularly. Group C was lavaged with Yougui Recipe (10 ml/kg), while group A and group B were lavaged with the same amount of saline. The behavior of catch force, independent activities, the tail suspension, field experiment and water cleans maze experiment were observed after 6 weeks. RESULTS: Compared with Yougui Recipe, rats in model group: catch force and independent activity decreases; the tail suspension activities was less time. In the desert field experiments, the total distance in 10 min movement reduced significantly. In the water maze experiment, incubation period of escape had a long time obviously, total distance of activities reduced. CONCLUSION: Yougui Recipe can relieve the ethologic change of rat model of steroid-induced avascular necrosis of the femoral head.
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Corticoesteroides/toxicidad , Medicamentos Herbarios Chinos/farmacología , Necrosis de la Cabeza Femoral/inducido químicamente , Actividad Motora/efectos de los fármacos , Animales , Necrosis de la Cabeza Femoral/psicología , Suspensión Trasera , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratas , Ratas WistarRESUMEN
Omphalia lapidescens is an important medicinal fungus as well as traditional Chinese medicine used for disease treatment. It is mainly used as a vermifuge for anthelmintic therapy, but it has not been hitherto reported to possess antitumor activity. In this study, a purified bioactive protein in O. lapidescens (pPeOp) was obtained using polyvinylpyrrolidone (PVP) followed by gel filtration chromatography. To evaluate the in vitro antitumor activity of pPeOp in human gastric tumor cells (MC-4 and SGC-7901) and normal cells (MC-1), MTT assay and FCM assay were used and the morphological changes, cell viability, cell death rate and cell apoptosis rate of MC-4, SGC-7901 and MC-1 cells were estimated. The results showed that pPeOp could significantly reduce the cell viability of MC-4 and SGC-7901 cells in a concentration-dependent manner, with IC50 values of 236.05 and 156.28 µg/ml, respectively. The morphological observation also indicated a similar result. In FCM assays, a significant increase of cell death rate and cell apoptosis rate of the tumor cells were observed, indicating probable necrosis-inducing effects and/or apoptosis-inducing effects of pPeOp. Importantly, there was no significant effect of pPeOp on MC-1 cells in each assay, showing that pPeOp has no adverse effects on the normal cells. In conclusion, pPeOp is a newly discovered bioactive protein in O. lapidescens and this is the first report on antitumor activity of such a fungal protein. This may provide a meaningful basis for developing a new protein drug for treatment against cancer, especially gastric cancer.
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Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/farmacología , Povidona/química , Tricholoma/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citometría de Flujo , Humanos , Medicina Tradicional China , Neoplasias GástricasRESUMEN
BACKGROUND: Twenty-three isolates of Metarhizium anisopliae (Metschnikof) Sorokin and M. acridum (Driver & Milner) JF Bischoff, Rehner & Humber from non-aphid host insects around the globe were evaluated for their aphid biocontrol potential, which is not well known. RESULTS: The apterous adults of green peach aphid Myzus persicae (Sulzer) were exposed to the fungal sprays of 11.5, 99 and 1179 conidia mm(-2) and blank control in three leaf-dish bioassays. All the tested isolates except one were proven to be infective to the aphid species at 21 +/- 1 degrees C and 14:10 h light:dark photoperiod, causing corrected mortalities of 10.1-95.3% at the high spore concentration. The data from ten isolates causing > 50% mortality at the high concentration were found to fit a time-concentration-mortality model well, yielding parameters for the estimates of their LC(50) and LT(50) that vary with post-spray time and spore concentration respectively. Four isolates of M. anisopliae (ARSEF 759, 4132, 2080 and 576) had LC(50) values of 44-80 conidia mm(-2) on day 8 and LT(50) values of 4.9-6.8 days at 100 conidia mm(-2), with 91-98% of the killed aphids being well mycotised after death. CONCLUSION: The Metarhizium infectivity to M. persicae differs greatly among the tested isolates. The four mentioned isolates with desired virulence and sporulation potential are excellent candidates for microbial control of aphids.
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Áfidos/microbiología , Metarhizium/fisiología , Control Biológico de Vectores/métodos , Animales , Relación Dosis-Respuesta a Droga , Dosificación Letal Mediana , Factores de TiempoRESUMEN
To clarify the potential use of hydrophobicity-related traits of aerial conidia in formulation design of fungal biocontrol agents, hydrophobicity rates (H (r)) and surface areas (S (a)) of aerial conidia were assessed with 48 strains of Beauveria bassiana, Isaria fumosorosea and Metarhizium spp. Inter- or intra-specific variation was large in H (r) (59.7-92.2%) and S (a) (7.9-25.3 microm(2) conidium(-1)) measurements, which were significantly correlated (r (2) = 0.55). Six isolates of the three fungi with distinguished H (r) and S (a) were further studied. Conidial wall proteins of these isolates were sequentially extracted with sodium dodecyl sulfate (SDS), formic acid (FA) and trifluoroacetic acid (TFA). Their H (r) values were significantly correlated to the contents (P (c)) of TFA-soluble, but FA-insoluble, proteins (2.7-44.8 microg per 10(7) conidia; r (2) = 0.79) and reduced drastically by the FA/TFA treatments, which eliminated the hydrophobin-based rodlet layers of conidial surfaces. However, the SDS treatments had no effect on either H (r) or rodlet layers. The dispersancy of a tested emulsifier to oil formulations of the six isolates in water was adversely correlated to their H (r) (r (2) = 0.94). The results indicate that both P (c) and S (a) are inherent hydrophobicity-related traits and can be utilized to select fungal biocontrol candidates for improved formulation and application.
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Proteínas Fúngicas/química , Hongos , Interacciones Hidrofóbicas e Hidrofílicas , Control Biológico de Vectores , Esporas Fúngicas/fisiología , Propiedades de Superficie , Beauveria/fisiología , Pared Celular/química , Pared Celular/fisiología , Diseño de Fármacos , Proteínas Fúngicas/fisiología , Hongos/clasificación , Hongos/fisiología , Hypocreales/fisiología , Proteínas de la Membrana/química , Metarhizium/fisiologíaRESUMEN
A cell wall protein, CWP10, resolved from the conidial formic acid extract of a Metarhizium anisopliae isolate, was characterized as a new 9.9-kDa protein with a 32-aa signal peptide with a central hydrophobic region (ca. 10 residues) at its N-terminus. This protein was proven neither to be hydrophobic nor glycosylated and encoded by a 363-bp, single-copy gene with three introns. CWP10 was existent in the conidial extracts of seven of 18 tested M. anisopliae isolates and much more abundant (immunogold-labeled) on conidial walls than in cytoplasm. Integrating the gene into a CWP10-absent strain of Beauveria bassiana led to excellent expression of CWP10 in aerial conidia, increasing net conidial hydrophobicity by 10.8% or adhesion to hydrophobic Teflon by 1.3-fold. However, the expressed protein had no effect on conidial tolerance to thermal and ultraviolet stresses. This is the first report on a non-hydrophobic cell-wall protein enhancing conidial hydrophobicity and adhesion of the fungal species.
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Beauveria/fisiología , Pared Celular/fisiología , Proteínas Fúngicas/fisiología , Metarhizium/fisiología , Esporas Fúngicas/fisiología , Secuencia de Aminoácidos , Secuencia de Bases , Beauveria/genética , Western Blotting , Adhesión Celular/efectos de la radiación , Pared Celular/química , Clonación Molecular , ADN de Hongos , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/aislamiento & purificación , Interacciones Hidrofóbicas e Hidrofílicas , Inmunohistoquímica , Metarhizium/química , Metarhizium/genética , Datos de Secuencia Molecular , Esporas Fúngicas/química , Esporas Fúngicas/efectos de la radiación , Rayos UltravioletaRESUMEN
The fungal biocontrol agents Metarhizium species and varieties have been widely applied for insect control but their targets rarely aim at sucking-type homopteran insects such as aphids. To search for fungal candidates against aphids, 16 strains of four varieties of two Metarhizium species, most of which originally infected foliage insect pests in Asia, Africa and America, were bioassayed to compare their virulence to Myzus persicae apterae. With each strain, each of three conidial suspensions was sprayed onto aphids in three Petri dishes (about 40 aphids per dish) in a Potter Spray Tower, resulting in deposits of conidia for low, medium and high dosage treatments (no. conidia/mm2). After spray, all aphids were reared at the regime of 25 +/- 1 degree C and 12:12 L:D and observed daily for counts of mycosed cadavers. As a result, 10 strains of M. anisopliae (Ma) and M. anisopliae var. anisopliae (Maa) caused 67%-100% mortalities at the high dosage of about 1000 conidia/mm2 within 7 days after spray whereas other strains, including M. anisopliae var. majus, M. anisopliae var. acridum, M. flavoviride var. minus, killed a very small number of aphids even at the high conidial dosage. Of the 10 strains, Ma 456 and Maa 3332 were highly virulent to the aphid species based the modeling of their time-dose-mortality data. The LC50 of the two strains were estimated as 113 and 260 conidia/mm2 on day 4, 32 and 43 conidia/mm2 on day 5, 17 and 26 conidia/mm2 on day 6, and only 11.4 and 19.9 conidia/mm2 on day 7, respectively. Thus, both strains are highly potential for use in microbial control of aphids.