RESUMO
Carbohydrate intolerance, commonly linked to the consumption of lactose, fructose, or sorbitol, affects up to 30% of the population in high-income countries. Although sorbitol intolerance is attributed to malabsorption, the underlying mechanism remains unresolved. Here, we show that a history of antibiotic exposure combined with high fat intake triggered long-lasting sorbitol intolerance in mice by reducing Clostridia abundance, which impaired microbial sorbitol catabolism. The restoration of sorbitol catabolism by inoculation with probiotic Escherichia coli protected mice against sorbitol intolerance but did not restore Clostridia abundance. Inoculation with the butyrate producer Anaerostipes caccae restored a normal Clostridia abundance, which protected mice against sorbitol-induced diarrhea even when the probiotic was cleared. Butyrate restored Clostridia abundance by stimulating epithelial peroxisome proliferator-activated receptor-gamma (PPAR-γ) signaling to restore epithelial hypoxia in the colon. Collectively, these mechanistic insights identify microbial sorbitol catabolism as a potential target for approaches for the diagnosis, treatment, and prevention of sorbitol intolerance.
Assuntos
Erros Inatos do Metabolismo dos Carboidratos , Microbioma Gastrointestinal , Sorbitol , Animais , Camundongos , Antibacterianos/farmacologia , Butiratos , Clostridium , Escherichia coli , Sorbitol/metabolismoRESUMO
The serious threats posed by drug-resistant bacterial infections and recent developments in synthetic biology have fueled a growing interest in genetically engineered phages with therapeutic potential. To date, many investigations on engineered phages have been limited to proof of concept or fundamental studies using phages with relatively small genomes or commercially available "phage display kits". Moreover, safeguards supporting efficient translation for practical use have not been implemented. Here, we developed a cell-free phage engineering and rebooting platform. We successfully assembled natural, designer, and chemically synthesized genomes and rebooted functional phages infecting gram-negative bacteria and acid-fast mycobacteria. Furthermore, we demonstrated the creation of biologically contained phages for the treatment of bacterial infections. These synthetic biocontained phages exhibited similar properties to those of a parent phage against lethal sepsis in vivo. This efficient, flexible, and rational approach will serve to accelerate phage biology studies and can be used for many practical applications, including phage therapy.
Assuntos
Infecções Bacterianas , Bacteriófagos , Terapia por Fagos , Humanos , Bacteriófagos/genética , Contenção de Riscos Biológicos , Biologia Sintética , Infecções Bacterianas/terapiaRESUMO
Adenosine diphosphate (ADP) ribosylation is a reversible posttranslational modification involved in the regulation of numerous cellular processes. Prototype ADP ribosyltransferases (ARTs) from many pathogenic bacteria are known to function as toxins, while other bacterial ARTs have just recently emerged. Recent studies have shown that bacteria also possess enzymes that function as poly-ADP ribose (ADPr) glycohydrolases (PARGs), which reverse poly-ADP ribosylation. However, how bacteria manipulate host target proteins by coordinated reactions of ARTs and ADPr hydrolases (ARHs) remains elusive. The intracellular bacterial pathogen Legionella pneumophila, the causative agent of Legionnaires' disease, transports a large array of effector proteins via the Dot/Icm type IV secretion system to host cells. The effector proteins, which mostly function as enzymes, modulate host cellular processes for the bacteria's benefit. In this study, we identified a pair of L. pneumophila effector proteins, Lpg0080 and Lpg0081, which function as an ART and an ARH, respectively. The two proteins were shown to coordinately modulate mitochondrial ADP/adenosine triphosphate (ATP) translocases (ANTs) by their enzymatic activities to conjugate ADPr to, and remove it from, a key arginine residue. The crystal structures of Lpg0081 and the Lpg0081:ADPr complex indicated that Lpg0081 is a macroD-type ARH with a noncanonical macrodomain, whose folding topology is strikingly distinct from that of the canonical macrodomain that is ubiquitously found in eukaryotic PARGs and ARHs. Our results illustrate that L. pneumophila has acquired an effector pair that coordinately manipulate mitochondrial activity via reversible chemical modification of ANTs.
Assuntos
Legionella pneumophila , Legionella , Difosfato de Adenosina , Trifosfato de Adenosina , Proteínas de Bactérias , Mitocôndrias/fisiologia , Translocases Mitocondriais de ADP e ATPRESUMO
Both inorganic fertilizer inputs and crop yields have increased globally, with the concurrent increase in the pollution of water bodies due to nitrogen leaching from soils. Designing agroecosystems that are environmentally friendly is urgently required. Since agroecosystems are highly complex and consist of entangled webs of interactions between plants, microbes, and soils, identifying critical components in crop production remain elusive. To understand the network structure in agroecosystems engineered by several farming methods, including environmentally friendly soil solarization, we utilized a multiomics approach on a field planted with Brassica rapa We found that the soil solarization increased plant shoot biomass irrespective of the type of fertilizer applied. Our multiomics and integrated informatics revealed complex interactions in the agroecosystem showing multiple network modules represented by plant traits heterogeneously associated with soil metabolites, minerals, and microbes. Unexpectedly, we identified soil organic nitrogen induced by soil solarization as one of the key components to increase crop yield. A germ-free plant in vitro assay and a pot experiment using arable soils confirmed that specific organic nitrogen, namely alanine and choline, directly increased plant biomass by acting as a nitrogen source and a biologically active compound. Thus, our study provides evidence at the agroecosystem level that organic nitrogen plays a key role in plant growth.
Assuntos
Brassica rapa/crescimento & desenvolvimento , Produção Agrícola , Produtos Agrícolas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Solo/química , Alanina/química , Alanina/metabolismo , Biomassa , Brassica rapa/metabolismo , Colina/química , Colina/metabolismo , Produtos Agrícolas/metabolismo , Conjuntos de Dados como Assunto , Redes e Vias Metabólicas/efeitos da radiação , Metabolômica , Microbiota/fisiologia , Microbiota/efeitos da radiação , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Rizosfera , Microbiologia do Solo , Luz SolarRESUMO
BACKGROUND: Hyaluronan (HA) has a unique hydration capacity that contributes to firmness and bounciness of the skin. Epidermal HA declines with skin aging, which may lead to clinical signs of aging including skin wrinkles and loss of hydration and elasticity. Recently, we developed a new cosmetic agent 1-ethyl-ß-N-acetylglucosaminide (ß-NAG2), which enhances HA production in cultured human keratinocytes. The aim of this study was to explore antiaging potential of ß-NAG2 in reconstructed human epidermal models and human clinical trial. MATERIALS AND METHODS: The amount of HA in ß-NAG2-treated epidermal models by topical application was analyzed by enzyme-linked immunosorbent assay (ELISA)-like assay. A randomized, double-blind and placebo-controlled study was conducted in Japanese females (n = 33) by topically treating each side of the face with a lotion formulated with ß-NAG2 or placebo for 8 weeks. RESULTS: Topically applied ß-NAG2 dose dependently increased HA production in epidermal models. Treatment with ß-NAG2-formulated lotion significantly improved skin hydration and elasticity and reduced skin wrinkling in crow's foot areas when compared to the placebo formulation. CONCLUSION: Topically applied ß-NAG2 promoted epidermal HA production in vitro and showed antiwrinkle activity in vivo accompanying the improvement in skin hydration and elasticity. Our study provides a novel strategy for antiwrinkle care through ß-NAG2-induced epidermal HA production.
Assuntos
Ácido Hialurônico , Envelhecimento da Pele , Epiderme , Feminino , Humanos , Queratinócitos , PeleRESUMO
An 82-year-old Japanese male patient was initially diagnosed with lymphocytosis. His complete blood count revealed a white blood cell count of 30.9×109/l with 81% abnormal lymphocytes. The abnormal lymphocytes included monoclonal clones of CD38+ and CD138+cytoplasmic κ+ and IgG-κ M-protein, which led to the final diagnosis of plasma cell leukemia (PCL). Bortezomib and dexamethasone therapy was initiated, but the patient succumbed to the disease on the 8th day of hospitalization. A cytogenetic examination revealed a t (9;14)(p13;q32) translocation and the Western blotting confirmed high PAX5 expression. Similar to our present case, PCL cases with "lymphocytosis" have been widely reported, which some speculating the involvement of PAX5 overexpression in the pathogenesis. Such cases, including ours, may be classified as a unique group of disorders (PCL presenting as "lymphocytosis"), which requires accurate differential diagnosis and subsequent urgent multidisciplinary intensive treatment.
Assuntos
Leucemia Plasmocitária , Linfocitose , Idoso de 80 Anos ou mais , Humanos , Masculino , Leucemia Plasmocitária/diagnóstico , Linfócitos/metabolismo , Linfocitose/diagnóstico , Fator de Transcrição PAX5/genética , Translocação GenéticaRESUMO
BACKGROUND: Multi-contrast Jones matrix optical coherence tomography (JM-OCT) can provide quantitative depth-resolved local optical properties by improving the measurement algorithm. MATERIALS AND METHODS: We examined the relationship between depth-resolved local optical properties of eye-corner skin measured by JM-OCT and corresponding wrinkle morphology of aged women (n = 21; age range, 71.7 ± 1.7 years). Wrinkle morphology was analyzed by measuring the surface topography of three-dimensional replicas. The same regions were measured three-dimensionally by JM-OCT, and the local optical properties at each depth were computed. RESULTS: Birefringence (BR) and mean wrinkle depth correlated significantly at a depth of 88.2-138.6 µm from the skin surface, and attenuation coefficient (AC) and mean wrinkle depth correlated significantly at a depth of 12.6-18.9 µm and 189-459.9 µm from the skin surface, although a degree of polarization uniformity (DOPU) did not. Stepwise multiple regression analysis demonstrated that a significant regression equation (R2 = 0.649, P < .001) for predicting mean wrinkle depth was determined by BR at 107.1 µm depth (BR 107.1 µm ), DOPU at 170.1 µm (DOPU 170.1µm ), and AC at 252 µm (AC 252 µm ) as independent variables and that these standardized beta regression coefficients were -0.860, -0.593, and -0.440, respectively, suggesting that BR, DOPU, and AC sufficiently explained mean wrinkle depth. CONCLUSION: These results suggest that BR 107.1 µm , DOPU 170.1 µm, and AC 252 µm may indicate collagen-related structure in the papillary, upper-reticular dermis, and microstructure or tissue density in reticular dermis, respectively, and may be involved in wrinkle formation.
Assuntos
Envelhecimento da Pele , Tomografia de Coerência Óptica , Idoso , Algoritmos , Humanos , Pele/diagnóstico por imagemRESUMO
BACKGROUND: Vibrio vulnificus hemolysin (VVH) is a pore-forming toxin secreted by Vibrio vulnificus. Cellular cholesterol was believed to be the receptor for VVH, because cholesterol could bind to VVH and preincubation with cholesterol inhibited cytotoxicity. It has been reported that specific glycans such as N-acetyl-D-galactosamine and N-acetyl-D-lactosamine bind to VVH, however, it has not been known whether these glycans could inhibit the cytotoxicity of VVH without oligomer formation. Thus, to date, binding mechanisms of VVH to cellular membrane, including specific receptors have not been elucidated. RESULTS: We show here that VVH associates with ganglioside GM1a, Fucosyl-GM1, GD1a, GT1c, and GD1b by glycan array. Among them, GM1a could pulldown VVH. Moreover, the GD1a inhibited the cytotoxicity of VVH without the formation of oligomers. CONCLUSION: This is the first report of a molecule able to inhibit the binding of VVH to target cells without oligomerization of VVH.
Assuntos
Membrana Celular/metabolismo , Gangliosídeos/farmacologia , Proteínas Hemolisinas/metabolismo , Vibrio vulnificus/patogenicidade , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação/efeitos dos fármacos , Células CHO , Colesterol/metabolismo , Cricetulus , Glicômica/métodos , Proteínas Hemolisinas/química , Análise em Microsséries , Ligação Proteica/efeitos dos fármacos , Conformação Proteica , Multimerização Proteica/efeitos dos fármacos , Vibrio vulnificus/metabolismoRESUMO
In response to environmental stressors such as blast fungal infections, rice produces phytoalexins, an antimicrobial diterpenoid compound. Together with momilactones, phytocassanes are among the major diterpenoid phytoalexins. The biosynthetic genes of diterpenoid phytoalexin are organized on the chromosome in functional gene clusters, comprising diterpene cyclase, dehydrogenase, and cytochrome P450 monooxygenase genes. Their functions have been studied extensively using in vitro enzyme assay systems. Specifically, P450 genes (CYP71Z6, Z7; CYP76M5, M6, M7, M8) on rice chromosome 2 have multifunctional activities associated with ent-copalyl diphosphate-related diterpene hydrocarbons, but the in planta contribution of these genes to diterpenoid phytoalexin production remains unknown. Here, we characterized cyp71z7 T-DNA mutant and CYP76M7/M8 RNAi lines to find that potential phytoalexin intermediates accumulated in these P450-suppressed rice plants. The results suggested that in planta, CYP71Z7 is responsible for C2-hydroxylation of phytocassanes and that CYP76M7/M8 is involved in C11α-hydroxylation of 3-hydroxy-cassadiene. Based on these results, we proposed potential routes of phytocassane biosynthesis in planta.
Assuntos
Cromossomos de Plantas , Sistema Enzimático do Citocromo P-450/genética , Oryza/genética , Sesquiterpenos/metabolismo , Hidroxilação , Mutação , RNA Mensageiro/genética , FitoalexinasRESUMO
Vibrio vulnificus secretes a hemolysin/cytolysin (VVH) that induces cytolysis against a variety of mammalian cells by forming pores on the cellular membrane. VVH is known to bind to the cellular membrane as a monomer, and then convert to a pore-forming oligomer. However, the structural basis for binding of this toxin to target cells remains unknown. We show here that the polarity and indole ring on the side chain of Trp 246 (W246) of VVH, which sits on a bottom loop, participates in binding to cellular membrane. To clarify the binding mechanisms of VVH, we generated a series of W246 point mutants that were substituted with Arg (W246R), Ala (W246A), or Tyr (W246Y), and tested their binding and cytotoxicity on Chinese hamster ovary (CHO) cells. At a final concentration of 1 µg/ml of VVH, wild type (Wt), W246A and W246Y could bind and induce cytotoxicity to CHO cells, whereas W246R could not. The cytotoxic activity of W246A was significantly lower than that of Wt. These findings indicate that both the polarity and indole ring on the side chain of W246 were involved in the binding of this toxin to the target cellular membrane. The indole ring plays a particularly important role in toxin binding.
Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/toxicidade , Proteínas Hemolisinas/química , Proteínas Hemolisinas/toxicidade , Triptofano/química , Vibrio vulnificus/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Células CHO/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Citotoxinas/química , Citotoxinas/genética , Citotoxinas/metabolismo , Citotoxinas/toxicidade , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Mutação Puntual , Multimerização Proteica , Coelhos , Relação Estrutura-Atividade , Vibrio vulnificus/genéticaRESUMO
Vibrio vulnificus (V. vulnificus) is a halophilic gram-negative bacterium that inhabits coastal warm water and induce severe diseases such as primary septicemia. To investigate the mechanisms of rapid bacterial translocation on intestinal infection, we focused on outer membrane vesicles (OMVs), which are extracellular vesicles produced by Gram-negative bacteria and deliver virulence factors. However, there are very few studies on the pathogenicity or contents of V. vulnificus OMVs (Vv-OMVs). In this study, we investigated the effects of Vv-OMVs on host cells. Epithelial cells INT407 were stimulated with purified OMVs and morphological alterations and levels of lactate dehydrogenase (LDH) release were observed. In cells treated with OMVs, cell detachment without LDH release was observed, which exhibited different characteristics from cytotoxic cell detachment observed in V. vulnificus infection. Interestingly, OMVs from a Vibrio Vulnificus Hemolysin (VVH) and Multifunctional-autoprocessing repeats-in -toxin (MARTX) double-deletion mutant strain also caused cell detachment without LDH release. Our results suggested that the proteolytic function of a serine protease contained in Vv-OMVs may contribute to pathogenicity of V. vulnificus by assisting bacterial translocation. This study reveals a new pathogenic mechanism during V. vulnificus infections. J. Med. Invest. 71 : 102-112, February, 2024.
Assuntos
Vesículas Extracelulares , Vibrio vulnificus , Vibrio vulnificus/patogenicidade , Vibrio vulnificus/metabolismo , Humanos , Vesículas Extracelulares/metabolismo , Proteínas Hemolisinas/metabolismo , L-Lactato Desidrogenase/metabolismo , Membrana Externa Bacteriana/metabolismo , Células Epiteliais/microbiologiaRESUMO
The gut microbiota prevents harmful microbes from entering the body, a function known as colonization resistance. The enteric pathogen Salmonella enterica serovar (S.) Typhimurium uses its virulence factors to break colonization resistance through unknown mechanisms. Using metabolite profiling and genetic analysis, we show that the initial rise in luminal pathogen abundance was powered by a combination of aerobic respiration and mixed acid fermentation of simple sugars, such as glucose, which resulted in their depletion from the metabolome. The initial rise in the abundance of the pathogen in the feces coincided with a reduction in the cecal concentrations of acetate and butyrate and an increase in epithelial oxygenation. Notably, these changes in the host environment preceded changes in the microbiota composition. We conclude that changes in the host environment can weaken colonization resistance even in the absence of overt compositional changes in the gut microbiota.
Assuntos
Fezes , Microbioma Gastrointestinal , Salmonella typhimurium , Microbioma Gastrointestinal/fisiologia , Salmonella typhimurium/metabolismo , Animais , Fezes/microbiologia , Camundongos , Fatores de Virulência/metabolismo , Metaboloma , Acetatos/metabolismo , Camundongos Endogâmicos C57BL , Butiratos/metabolismo , Ceco/microbiologia , Feminino , FermentaçãoRESUMO
Recent reports have revealed genomic clustering of enzymatic genes for particular biosynthetic pathways in plant specialized/secondary metabolism. Rice (Oryza sativa) carries two such clusters for production of antimicrobial diterpenoid phytoalexins, with the cluster on chromosome 2 containing four closely related/homologous members of the cytochrome P450 CYP76M subfamily (CYP76M5-8). Notably, the underlying evolutionary expansion of these CYP appears to have occurred after assembly of the ancestral biosynthetic gene cluster, suggesting separate roles. It has been demonstrated that CYP76M7 catalyzes C11α-hydroxylation of ent-cassadiene, and presumably mediates an early step in biosynthesis of the derived phytocassane class of phytoalexins. Here we report biochemical characterization of CYP76M5, -6, and -8. Our results indicate that CYP76M8 is a multifunctional/promiscuous hydroxylase, with CYP76M5 and -7 seeming to provide only redundant activity, while CYP76M6 seems to provide both redundant and novel activity, relative to CYP76M8. RNAi-mediated double knockdown of CYP76M7 and -8 suppresses elicitor inducible phytocassane production, indicating a role for these monooxygenases in phytocassane biosynthesis. In addition, our data suggests that CYP76M5, -6, and -8 may play redundant roles in production of the oryzalexin class of phytoalexins as well. Intriguingly, the preceding diterpene synthase for oryzalexin biosynthesis, unlike that for the phytocassanes, is not found in the chromosome 2 diterpenoid biosynthetic gene cluster. Accordingly, our results not only uncover a complex evolutionary history, but also further suggest some intriguing differences between plant biosynthetic gene clusters and the seemingly similar microbial operons. The implications for the underlying metabolic evolution of plants are then discussed.
Assuntos
Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Família Multigênica/genética , Oryza/enzimologia , Oryza/genética , Vias Biossintéticas/genética , Cromossomos de Plantas/genética , Diterpenos/metabolismo , Metabolismo Energético/genética , Evolução Molecular , Regulação da Expressão Gênica de Plantas/fisiologia , Técnicas de Silenciamento de Genes , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sesquiterpenos/metabolismo , FitoalexinasRESUMO
Vibrio vulnificus is a bacterium that inhabits warm seawater or brackish water environments and causes foodborne diseases and wound infections. In severe cases, V. vulnificus invades the skeletal muscle tissue, where bacterial proliferation leads to septicemia and necrotizing fasciitis with high mortality. Despite this characteristic, information on metabolic changes in tissue infected with V. vulnificus is not available. Here, we elucidated the metabolic changes in V. vulnificus-infected mouse skeletal muscle using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). Metabolome analysis revealed changes in muscle catabolites and energy metabolites during V. vulnificus infection. In particular, succinic acid accumulated but fumaric acid decreased in the infected muscle. However, the virulence factor deletion mutant revealed that changes in metabolites and bacterial proliferation were abolished in skeletal muscle infected with a multifunctional-autoprocessing repeats-in-toxin (MARTX) mutant. On the other hand, mice that were immunosuppressed via cyclophosphamide (CPA) treatment exhibited a similar level of bacterial counts and metabolites between the wild type and MARTX mutant. Therefore, our data indicate that V. vulnificus induces metabolic changes in mouse skeletal muscle and proliferates by using the MARTX toxin to evade the host immune system. This study indicates a new correlation between V. vulnificus infections and metabolic changes that lead to severe reactions or damage to host skeletal muscle. IMPORTANCE V. vulnificus causes necrotizing skin and soft tissue infections (NSSTIs) in severe cases, with high mortality and sign of rapid deterioration. Despite the severity of the infection, the dysfunction of the host metabolism in skeletal muscle triggered by V. vulnificus is poorly understood. In this study, by using a mouse wound infection model, we revealed characteristic changes in muscle catabolism and energy metabolism in skeletal muscle associated with bacterial proliferation in the infected tissues. Understanding such metabolic changes in V. vulnificus-infected tissue may provide crucial information to identify the mechanism via which V. vulnificus induces severe infections. Moreover, our metabolite data may be useful for the recognition, identification, or detection of V. vulnificus infections in clinical studies.
Assuntos
Toxinas Bacterianas , Vibrioses , Humanos , Toxinas Bacterianas/metabolismo , Vibrioses/microbiologia , Fatores de Virulência/metabolismo , Músculo Esquelético/metabolismoRESUMO
OBJECTIVE: Despite the development of newly developed drugs, most multiple myeloma (MM) patients with high-risk cytogenetic abnormalities such as t(4;14) or del17p relapse at anin early stage of their clinical course. We previously reported that a natural product,komaroviquinone (KQN), isolated from the perennial semi-shrub Dracocephalum komarovi, i.e., komaroviquinone (KQN) and its derivative GTN024 induced the apoptosis of MM cells by producing reactive oxygen species (ROS), but both exhibited significant hematological toxicity. Aim of this study is to clarify anti-tumor activity, safety and pharmacokinetics of GTN057, an optimization compound of KQN in vivo. METHODS: ICR/SCID xenograft model of KMS11, a t(4;14) translocation-positive MM cell line, was used for in vivo study. Mice pharmacokinetics of GTN057 and the degradation products were analyzed by LC-MS/MS. RESULTS: Herein, our in vitro experiments revealed that GTN057 is much less toxic to normal hematopoietic cells, induced the apoptosis of both MM cell lines andpatient samples, including those with high-risk cytogenetic changes. A xenograft model of a high-risk MM cell line demonstrated that GTN057 significantly delayed the tumor growth with no apparent hematological or systemic toxicities in vivo. The pathological examination of GTN057-treated tumors in vivoshowed revealed apoptosis of MM cells and anti-angiogenesis. In addition to the production of ROS, GTN057 inhibited the downstream signaling of c-MET, a receptor tyrosine kinase a receptor forand hepatocyte growth factor (HGF) receptor. Thus, GTN057 is less toxic and is able tomay be a candidate drug for treating MM patients, via multifunctional mechanisms. We have also extensively studied the pharmacologyical analysis of GTN057. The metabolites of GTN057, (e.g.,such as GTN054), may also have anti-tumorantitumor activity. CONCLUSION: Natural products or and their derivatives can could be good sources of antineoplastic drugs even for high-risk cancer.
Assuntos
Mieloma Múltiplo , Humanos , Camundongos , Animais , Mieloma Múltiplo/patologia , Espécies Reativas de Oxigênio , Cromatografia Líquida , Camundongos Endogâmicos ICR , Linhagem Celular Tumoral , Camundongos SCID , Espectrometria de Massas em Tandem , Recidiva Local de Neoplasia , ApoptoseRESUMO
Chondroitinase ABC (ChABC) is an enzyme that degrades glycosaminoglycan side-chains of chondroitin sulfate (CS-GAG) from the chondroitin sulfate proteoglycan (CSPG) core protein. Previous studies demonstrated that the administration of ChABC after spinal cord injury promotes nerve regeneration by removing CS-GAGs from the lesion site and promotes the plasticity of spinal neurons by removing CS-GAGs from the perineuronal nets (PNNs). These effects of ChABC might enhance the regeneration and sprouting of descending axons, leading to the recovery of motor function. Anatomical evidence, indicating that the regenerated axons innervate spinal motoneurons caudal to the lesion site, however, has been lacking. In the present study, we investigated whether descending axons pass through the lesion site and innervate the lumbar motoneurons after ChABC administration in rats with complete spinal cord transection (CST) at the thoracic level. At 3 weeks after CST, 5-hydroxytryptamine (5-HT) fibers were observed to enter the lesion in ChABC-treated rats, but not saline-treated rats. In addition, 92% of motoneurons in the ventral horn of the fifth lumbar segment (L5) in saline-treated rats, and 38% of those in ChABC-treated rats were surrounded by chondroitin sulfate-A (CS-A) positive structures. At 8 weeks after CST, many 5-HT fibers were observed in the ventral horn of the L5, where they terminated in the motoneurons in ChABC-treated rats, but not in saline-treated rats. In total, 54% of motoneurons in the L5 ventral horn in saline-treated rats and 39% of those in ChABC-treated rats were surrounded by CS-A-positive structures. ChABC-treated rats had a Basso, Beattie, and Bresnahan (BBB) motor score of 3.8 at 2 weeks, 7.1 at 3 weeks, and 10.3 at 8 weeks after CST. These observations suggest that ChABC administration to the lesion site immediately after CST may promote the regeneration of descending 5-HT axons through the lesion site and their termination on motoneurons at the level of caudal to the lesion site. ChABC administration might facilitate reinnervation by degrading CS-GAGs around motoneurons. Motor function of the lower limbs was significantly improved in ChABC-treated rats even before the 5-HT axons terminated on the motoneurons, suggesting that other mechanisms may also contribute to the motor function recovery.
RESUMO
Vibrio vulnificus is known to cause necrotizing soft tissue infections (NSTIs). However, the pathogenic mechanism causing cellulitis, necrotizing fasciitis, muscle necrosis, and rapidly developing septicemia in humans have not been fully elucidated. Here, we report a multilayer analysis of tissue damage after subcutaneous bacterial inoculation as a murine model of V. vulnificus NSTIs. Our histopathological examination showed the progression of cellulitis, necrotizing fasciitis, and muscle necrosis worsening as the infection penetrated deeper into the muscle tissue layers. The increase in vascular permeability was the primary cause of the swelling and congestion, which are acute signs of inflammation in soft tissue and characteristic of human NSTIs. Most importantly, our sequential analysis revealed for the first time that V. vulnificus not only spreads along the skin and subcutaneous tissues or fascia but also invades deeper muscle tissues beyond the fascia as the crucial process of its lethality. Also, increased vascular permeability enabled V. vulnificus to proliferate in muscle tissue and enter the systemic circulation, escalating the bacterium's lethality. Our finding may yield important clinical benefits to patients by helping physicians understand the impact of surgical debridement on the patient's quality of life. Furthermore, this study provides a promising system to accelerate studies of virulence factors and eventually help establish new therapies.
RESUMO
We herein report a case of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-ALL) that was incidentally detected by fluorodeoxyglucose-positron emission tomography (18F-FDG PET)/computed tomography (CT) at a health checkup. At that time, the findings of a physical examination and blood tests were all normal, except for the diffuse bone marrow uptake (maximum standardized uptake value: 6.3). One month later, when the blood counts remained in the normal ranges, a bone marrow examination confirmed the diagnosis of Ph-ALL. Although a diffuse bone marrow uptake of 18F-FDG is observed in some benign conditions, physicians should also consider the possibility of hematological malignancies, including acute leukemia, even when that is the only abnormal finding.
Assuntos
Fluordesoxiglucose F18 , Leucemia-Linfoma Linfoblástico de Células Precursoras , Doença Aguda , Humanos , Cromossomo Filadélfia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico por imagem , Compostos Radiofarmacêuticos , Estudos RetrospectivosRESUMO
Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative disease accompanied by mutations in CSF3R. Here, we present a patient with CNL who developed to acute myeloid leukemia (AML) at the same time that a t(4;12)(q12;p13) translocation appeared. The uniqueness of this cytogenetic abnormality led us to delineate the molecular aberrations relevant for clonal evolution. While the CSF3R mutation was present throughout the course of the disease, the SETBP1 mutation was newly acquired at the AML transformation. The present case suggests that careful monitoring of t(4;12)(q12;p13) and SETBP1 is crucial to predict AML evolution in CNL patients.
RESUMO
Background: The loss of E-cadherin expression and the induction of N-cadherin are known as hallmarks of the epithelial-to-mesenchymal transition, an essential initial step in the process of metastasis in solid tumors. Although several studies have reported expressions of these cadherins in patients with multiple myeloma (MM), their clinical significance is unknown as MM cells are non-epithelial. Methods: In this study, we examined the expression of E- and N-cadherins by immunohistochemistry using bone marrow (BM) biopsy specimens from 31 newly diagnosed MM patients and in subsequent biopsy specimens from six of these. Results: Negative E-cadherin expression on BM myeloma cell membranes was significantly associated with the presence of soft-tissue masses arising from bone lesions and breaking through the cortical bone, referred to as extramedullary disease (EMD). Conclusions: Given the aggressive nature of EMD, our study suggests that screening for E-cadherin using BM immunohistochemistry is one measure that could predict the development of EMD in patients with MM.