RESUMEN
Abietic acid (AA), dehydroabietic acid (DHA) and triptoquinones (TQs) are bioactive abietane-type diterpenoids, which are present in many edible vegetables and medicinal herbs with health-promoting properties. Evidence suggests that beneficial effects of diterpenes operate, at least in part, through effects on cells in the immune system. Dendritic cells (DCs) are a key type of leukocyte involved in the initiation and regulation of the immune/inflammatory response and natural or synthetic compounds that modulate DC functions could be potential anti-inflammatory/immunomodulatory agents. Herein, we report the screening of 23 known semisynthetic AA and DHA derivatives, and TQs, synthesized previously by us, in a multi-analyte DC-based assay that detects inhibition of pro-inflammatory cytokine production. Based on the magnitude of the inhibitory effect observed and the number of cytokines inhibited, a variety of activities among compounds were observed, ranging from inactive/weak to very potent inhibitors. Structurally, either alcohol or methyl ester substituents on ring A along with the introduction of aromaticity and oxidation in ring C in the abietane skeleton were found in compounds with higher inhibitory properties. Two DHA derivatives and two TQs exhibited a significant inhibition in all pro-inflammatory cytokines tested and were further investigated. The results confirmed their ability to inhibit, dose dependently, LPS-stimulated expression of the co-stimulatory molecules CD40 and/or CD86 and the production of the pro-inflammatory cytokines IL-1ß, IL-6, IL-12 and TNFα. Our results demonstrate that DC maturation process can be targeted by semisynthetic DHA derivatives and TQ epimers and indicate the potential of these compounds as optimizable anti-inflammatory/immunomodulatory agents.
Asunto(s)
Abietanos , Factor de Necrosis Tumoral alfa , Abietanos/metabolismo , Abietanos/farmacología , Antiinflamatorios/metabolismo , Antiinflamatorios/farmacología , Citocinas/metabolismo , Células Dendríticas , Ésteres/farmacología , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
A mouse model of cutaneous leishmaniasis (CL) by Leishmania (Viannia) panamensis (L(V)p) that reproduces the characteristics of the human disease remains elusive. Here we report the development of a CL model that uses a mouse-adapted L(V)p isolate to reproducibly induce a dermal disease with a remarkable similarity to human CL. BALB/c mice infected intradermally in the ear with 105 stationary UA-946 L(V)p promastigotes develop a progressive cutaneous disease that exhibits the typical ulcerated lesions with indurated borders observed in CL patients. Although most of parasites in the inoculum die within the first week of infection, the survivors vigorously multiply at the infection site during the following weeks, paralleling disease appearance and aggravation. Regional lymphadenopathy as well as lymphatic dissemination of parasites to draining lymph nodes (dLN) was evidenced early after infection. Viable parasites were also isolated from spleen at later timepoints indicating systemic parasitic dissemination, but, strikingly, no signs of systemic disease were observed. Increasing numbers of myeloid cells and T lymphocytes producing IFNγ and IL-4 were observed in the dLN as disease progressed. A mixed adaptive L(V)p-specific T cell-mediated response was induced, since ex vivo recall experiments using dLN cells and splenocytes revealed the production of type 1 (IFNγ, IL-2), type 2 (IL-4, IL-13), regulatory (IL-10), and inflammatory (GM-CSF, IL-3) cytokines. Humoral adaptive response was characterized by early production of IgG1- followed by IgG2a-type of L(V)p-specific antibodies. IFNγ/IL-4 and IgG2a/IgG1 ratios indicated that the initial non-protective Th2 response was redirected toward a protective Th1 response. In situ studies revealed a profuse recruitment of myeloid cells and of IFNγ- and IL-4-producing T lymphocytes to the site of infection, and the typical histopathological changes induced by dermotropic Leishmania species. Evidence that this model is suitable to investigate pharmacological and immunomodulatory interventions, as well as for antigen discovery and vaccine development, is also presented. Altogether, these results support the validity and utility of this novel mouse model to study the pathogenesis, immunity, and therapeutics of L(V)p infections.
RESUMEN
One of the interventional strategies to reestablish the immune effector/regulatory balance, that is typically altered in chronic inflammatory diseases (CID), is the reinforcement of endogenous immunomodulatory pathways as the one triggered by interleukin (IL)-10. In a recent work, we demonstrated that the subcutaneous (sc) administration of an IL-10/Treg-inducing small molecule-based formulation, using a repetitive microdose (REMID) treatment strategy to preferentially direct the effects to the regional immune system, delays the progression of atherosclerosis. Here we investigated whether the same approach using other IL-10-inducing small molecule, such as the safe, inexpensive, and widely available polyphenol curcumin, could induce a similar protective effect in two different CID models. We found that, in apolipoprotein E deficient mice, sc treatment with curcumin following the REMID strategy induced atheroprotection that was not consequence of its direct systemic lipid-modifying or antioxidant activity, but instead paralleled immunomodulatory effects, such as reduced proatherogenic IFNγ/TNFα-producing cells and increased atheroprotective FOXP3+ Tregs and IL-10-producing dendritic and B cells. Remarkably, when a similar strategy was used in the neuroinflammatory model of experimental autoimmune encephalomyelitis (EAE), significant clinical and histopathological protective effects were evidenced, and these were related to an improved effector/regulatory cytokine balance in restimulated splenocytes. The essential role of curcumin-induced IL-10 for neuroprotection was confirmed by the complete abrogation of the clinical effects in IL-10-deficient mice. Finally, the translational therapeutic prospection of this strategy was evidenced by the neuroprotection observed in mice starting the treatment one week after disease triggering. Collectively, results demonstrate the power of a simple natural IL-10-inducing small molecule to tackle chronic inflammation, when its classical systemic and direct pharmacological view is shifted towards the targeting of regional immune cells, in order to rationally harness its immunopharmacological potential. This shift implies that many well-known IL-10-inducing small molecules could be easily reformulated and repurposed to develop safe, innovative, and accessible immune-based interventions for CID.
Asunto(s)
Curcumina/administración & dosificación , Agentes Inmunomoduladores/administración & dosificación , Inflamación/prevención & control , Interleucina-10/fisiología , Animales , Apolipoproteínas E/fisiología , Aterosclerosis/prevención & control , Enfermedad Crónica , Curcumina/farmacología , Lípidos/sangre , Ratones , Ratones Endogámicos C57BL , NeuroprotecciónRESUMEN
The targeting of proinflammatory pathways has a prophylactic and therapeutic potential on atherosclerotic cardiovascular diseases (CVD). An alternative/complementary strategy is the promotion of endogenous atheroprotective mechanisms that are impaired during atherosclerosis progression, such as the activity of tolerogenic dendritic cells (tolDC) and regulatory T cells (Treg). There is a need to develop novel low cost, safe and effective tolDC/Treg-inducing formulations that are atheroprotective and that can be of easy translation into clinical settings. We found that apolipoprotein E-deficient (ApoE-/-) mice treated with a low-dose combined formulation of Vitamin D and Dexamethasone (VitD/Dexa), delivered repetitively and subcutaneously (sc) promoted interleukin-10 (IL-10) production by dendritic cells and other antigen presenting cells in the lymph nodes draining the site of injection and the spleens. Expectedly, the treatment also increased the numbers of IL-10-producing CD4+ T cells. Concomitantly, the frequency of IFNγ-producing CD4+ and CD8+ T cells in the spleen, and the IFNγ response of splenocytes to polyclonal stimulation ex vivo were lower after VitD/Dexa treatment, indicating a reduced proatherogenic Th1 response. Interestingly, VitD/Dexa-treated mice had smaller atherosclerotic lesions, with reduced lipid content and lower inflammatory infiltrate of macrophages and T cells in the aortic root. No hypolipidemic or antioxidant effect could be detected, suggesting that a dominantly immunomodulatory mechanism of atheroprotection was engaged under the low-dose sc VitD/Dexa conditions used. Finally, no evidence of clinical, biochemical or immune toxicity was observed in treated ApoE-/- mice and, most importantly, C57BL/6 mice latently infected with Leishmania parasites and treated with an identical VitD/Dexa dose/scheme showed no clinical or microbiological signs of disease reactivation, suggesting the absence of general immunosuppression. Altogether, these results indicate that a non-toxic, non-immunosuppressive, low-dose of VitD/Dexa, administered subcutaneously and repetitively, exerts atheroprotective effects in dyslipidemic mice, apparently due to the induction of an IL-10-producing network of lymphoid and myeloid immune cells. These well known, widely available, and inexpensive small molecules can be easily co-formulated into a simple and accessible agent with a potential use as a prophylactic or therapeutic immune intervention for CVD and other chronic inflammatory diseases.
Asunto(s)
Aterosclerosis/prevención & control , Enfermedades Cardiovasculares/inmunología , Enfermedades Cardiovasculares/terapia , Dexametasona/farmacología , Interleucina-10/metabolismo , Vitamina D/farmacología , Animales , Apolipoproteínas E/deficiencia , Linfocitos T CD8-positivos/metabolismo , Enfermedades Cardiovasculares/metabolismo , Interferón gamma/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Linfocitos T Reguladores/metabolismoRESUMEN
Chlorogenic acids (CGA) are the most abundant phenolic compounds in green coffee beans and in the human diet and have been suggested to mitigate several cardiometabolic risk factors. Here, we aimed to evaluate the effect of a water-based standardized green coffee extract (GCE) on cardiometabolic parameters in ApoE-/- mice and to explore the potential underlying mechanisms. Mice were fed an atherogenic diet without (vehicle) or with GCE by gavage (equivalent to 220 mg/kg of CGA) for 14 weeks. We assessed several metabolic, pathological, and inflammatory parameters and inferred gut microbiota composition, diversity, and functional potential. Although GCE did not reduce atherosclerotic lesion progression or plasma lipid levels, it induced important favorable changes. Specifically, improved metabolic parameters, including fasting glucose, insulin resistance, serum leptin, urinary catecholamines, and liver triglycerides, were observed. These changes were accompanied by reduced weight gain, decreased adiposity, lower inflammatory infiltrate in adipose tissue, and protection against liver damage. Interestingly, GCE also modulated hepatic IL-6 and total serum IgM and induced shifts in gut microbiota. Altogether, our results reveal the cooccurrence of these beneficial cardiometabolic effects in response to GCE in the same experimental model and suggest potential mediators and pathways involved.
Asunto(s)
Apolipoproteínas E/metabolismo , Coffea/química , Dieta Alta en Grasa/efectos adversos , Microbioma Gastrointestinal/efectos de los fármacos , Extractos Vegetales/farmacología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/microbiología , Animales , Apolipoproteínas E/genética , Aterosclerosis , Metabolismo Energético/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Resistencia a la Insulina , Hígado/efectos de los fármacos , Hígado/microbiología , Cirrosis Hepática/prevención & control , Ratones , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Extractos Vegetales/químicaRESUMEN
The establishment of Leishmania infection in mammalian hosts and the subsequent manifestation of clinical symptoms require internalization into macrophages, immune evasion and parasite survival and replication. Although many of the genes involved in these processes have been described, the genetic and genomic variability associated to differences in virulence is largely unknown. Here we present the genomic variation of four Leishmania (Viannia) panamensis strains exhibiting different levels of virulence in BALB/c mice and its application to predict novel genes related to virulence. De novo DNA sequencing and assembly of the most virulent strain allowed comparative genomics analysis with sequenced L. (Viannia) panamensis and L. (Viannia) braziliensis strains, and showed important variations at intra and interspecific levels. Moreover, the mutation detection and a CNV search revealed both base and structural genomic variation within the species. Interestingly, we found differences in the copy number and protein diversity of some genes previously related to virulence. Several machine-learning approaches were applied to combine previous knowledge with features derived from genomic variation and predict a curated set of 66 novel genes related to virulence. These genes can be prioritized for validation experiments and could potentially become promising drug and immune targets for the development of novel prophylactic and therapeutic interventions.
Asunto(s)
Leishmania guyanensis/genética , Leishmania guyanensis/patogenicidad , Animales , Colombia , Variaciones en el Número de Copia de ADN , Femenino , Genoma de Protozoos , Leishmania braziliensis/genética , Leishmaniasis Mucocutánea/parasitología , Aprendizaje Automático , Ratones Endogámicos BALB C , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADNRESUMEN
The accumulation of oxidized ApoB-100-containing lipoproteins in the vascular intima and its subsequent recognition by macrophages results in foam cell formation and inflammation, key events during atherosclerosis development. Agents targeting this process are considered potentially atheroprotective. Since natural biflavonoids exert antioxidant and anti-inflammatory effects, we evaluated the atheroprotective effect of biflavonoids obtained from the tropical fruit tree Garcinia madruno. To this end, the pure biflavonoid aglycones morelloflavone (Mo) and volkensiflavone (Vo), as well as the morelloflavone's glycoside fukugiside (Fu) were tested in vitro in primary macrophages, whereas a biflavonoid fraction with defined composition (85% Mo, 10% Vo, and 5% Amentoflavone) was tested in vitro and in vivo. All biflavonoid preparations were potent reactive oxygen species (ROS) scavengers in the oxygen radical absorbance capacity assay, and most importantly, protected low-density lipoprotein particle from both lipid and protein oxidation. In biflavonoid-treated macrophages, the surface expression of the oxidized LDL (oxLDL) receptor CD36 was significantly lower than in vehicle-treated macrophages. Uptake of fluorescently labeled oxLDL and cholesterol accumulation were also attenuated in biflavonoid-treated macrophages and followed a pattern that paralleled that of CD36 surface expression. Fu and Vo inhibited oxLDL-induced ROS production and interleukin (IL)-6 secretion, respectively, whereas all aglycones, but not the glucoside Fu, inhibited the secretion of one or more of the cytokines IL-1ß, IL-12p70, and monocyte chemotactic protein-1 (MCP-1) in lipopolysaccharide (LPS)-stimulated macrophages. Interestingly, in macrophages primed with low-dose LPS and stimulated with cholesterol crystals, IL-1ß secretion was significantly and comparably inhibited by all biflavonoid preparations. Intraperitoneal administration of the defined biflavonoid fraction into ApoE-/- mice was atheroprotective, as evidenced by the reduction of the atheromatous lesion size and the density of T cells and macrophages infiltrating the aortic root; moreover, this treatment also lowered the circulating levels of cholesterol and the lipid peroxidation product malondialdehyde. These results reveal the potent atheroprotective effects exerted by biflavonoids on key events of the oxLDL-macrophage interphase: (i) atheroligand formation, (ii) atheroreceptor expression, (iii) foam cell transformation, and (iv) prooxidant/proinflammatory macrophage response. Furthermore, our results also evidence the antioxidant, anti-inflammatory, hypolipemiant, and atheroprotective effects of Garcinia madruno's biflavonoids in vivo.
RESUMEN
The evidence regarding the role of regulatory B cells (Breg) in atherosclerosis are scarce, and there are contradictory data about their atheroprotective properties. Due to the demonstrated protective function of Breg in different inflammatory diseases mainly through interleukin-10 (IL-10) production, the knowledge of their participation in atherosclerosis immunopathology would be very valuable. To further study which B cell subsets participate in IL-10 production and their regulatory role, splenocytes from apolipoprotein-E-deficient mice were evaluated by ex vivo and in vitro cultures. Atherosclerotic mice had increased frequency of IL-10+ B cells, which presented high CD1d, CD19, and IgM, but variable CD5, CD21, and CD23 expression. IL-10+ B cells were not enriched in B cell subsets previously reported as Breg. Increased frequency of IL-10+ B cells with transitional 1-like (T1-like) and follicular (FO) and reduced CD5+ and marginal zone (MZ) phenotypes were observed ex vivo. Increased frequency of IL-10+ B cells with T1-like and MZ, and decreased IL-10+ FO and T2 phenotypes were also observed in vitro. To determine regulatory capacity of B cells in the atherosclerotic model, each subset were co-cultured with CD4+CD25- T cells. CD5+, FO, MZ, and T1-like cells from atherosclerotic mice exhibited regulation in an IL-10-dependent manner. However, only FO cells decreased both frequency of interferon gamma (IFN-γ)+ and tumor necrosis factor alpha (TNF-α)+ and proliferation of T cells. Finally, splenocytes showed increased frequency of IFN-γ+ and TNF-α+ cells only when FO-depleted B cells were evaluated. These results suggest that mainly FO B cells can modulate in some level the inflammatory responses observed in atherosclerosis.
Asunto(s)
Aterosclerosis/inmunología , Subgrupos de Linfocitos B/inmunología , Linfocitos B Reguladores/inmunología , Interleucina-10/inmunología , Linfocitos T/inmunología , Animales , Proliferación Celular , Células Cultivadas , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Humanos , Tolerancia Inmunológica , Interferón gamma/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Cardiovascular diseases are the most common cause of death in the world, atherosclerosis being its main underlying disease. Information about the role of B cells during atherosclerotic process is scarce, but both proatherogenic and atheroprotective properties have been described in the immunopathology of this disease. Frequency and phenotype of B cell subpopulations were studied in wild type and apolipoprotein-E-deficient (apoE (-/-) ) mice fed or not with high-fat diet (HFD), by flow cytometry. Here, we provide the information about the materials, methods, analysis and additional information related to our study published in Atherosclerosis (DOI: 10.1016/j.atherosclerosis.2015.12.022, article reference: ATH14410) [1]. The data contained in this article shows and supports that mice with advanced atherosclerosis have a variety of alterations in frequency and phenotype of B cell subsets, most of which associated with dyslipidemia.
RESUMEN
Microsporidia are a group of intracellular pathogens causing self-limited and severe diseases in immunocompetent and immunocompromised individuals, respectively. A cellular type 1 adaptive response, mediated by IL-12, IFNγ, CD4+, and CD8+ T cells has been shown to be essential for host resistance, and dendritic cells (DC) play a key role at eliciting anti-microsporidial immunity. We investigated the in vitro response of DC and DC precursors/progenitors to infection with Encephalitozoon intestinalis (Ei), a common agent of human microsporidosis. Ei-exposed DC cultures up-regulated the surface expression of MHC class II and the costimulatory molecules CD86 and CD40, only when high loads of spores were used. A vigorous secretion of IL-6 but not of IL-1ß or IL-12p70 was also observed in these cultures. Ei-exposed DC cultures consisted of immature infected and mature bystander DC, as assessed by MHC class II and costimulatory molecules expression, suggesting that intracellular Ei spores deliver inhibitory signals in DC. Moreover, Ei selectively inhibited the secretion of IL-12p70 in LPS-stimulated DC. Whereas Ei-exposed DC promoted allogeneic naïve T cell proliferation and IL-2 and IFNγ secretion in DC-CD4+ T cell co-cultures, separated co-cultures with bystander or infected DCs showed stimulation or inhibition of IFNγ secretion, respectively. When DC precursors/progenitors were exposed to Ei spores, a significant inhibition of DC differentiation was observed without shifting the development toward cells phenotypically or functionally compatible with myeloid-derived suppressor cells. Neutralization experiments demonstrated that this inhibitory effect is IL-6-dependent. Altogether this investigation reveals a novel potential mechanism of immune escape of microsporidian parasites through the modulation of DC differentiation and maturation.
Asunto(s)
Células Dendríticas/citología , Células Dendríticas/inmunología , Encephalitozoon/inmunología , Encefalitozoonosis/inmunología , Evasión Inmune/inmunología , Interleucina-6/inmunología , Animales , Antígeno B7-2/biosíntesis , Linfocitos T CD4-Positivos/inmunología , Antígenos CD40/biosíntesis , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/inmunología , Células Cultivadas , Encefalitozoonosis/microbiología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Subunidad p35 de la Interleucina-12/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Esporas Bacterianas/inmunologíaRESUMEN
Lymphocytes, the cellular effectors of adaptive immunity, are involved in the chronic inflammatory process known as atherosclerosis. Proatherogenic and atheroprotective properties have been ascribed to B cells. However, information regarding the role of B cells during atherosclerosis is scarce. Both the frequency and the phenotype of B cell subpopulations were studied by flow cytometry in wild type and apolipoprotein-E-deficient (apoE(-/-)) mice fed a high-fat (HFD) or control diet. Whereas the proportion of follicular cells was decreased, transitional 1-like cells were increased in mice with advanced atherosclerotic lesions (apoE(-/-) HFD). B cells in atherosclerotic mice were more activated, indicated by their higher surface expression of CD80, CD86, CD40 and CD95 and increased serum IgG1 levels. In the aorta, a decreased frequency of B cells was observed in mice with advanced atherosclerosis. Low expression of CD19 was observed on B cells from the spleen, aorta and lymph nodes of apoE(-/-) HFD mice. This alteration correlated with serum levels of IgG1 and cholesterol. A reduction in CD19 expression was induced in splenic cells from young apoE(-/-) mice cultured with lipemic serum. These results show that mice with advanced atherosclerosis display a variety of alterations in the frequency and phenotype of B lymphocytes, most of which are associated with dyslipidemia.
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Aorta/inmunología , Enfermedades de la Aorta/inmunología , Aterosclerosis/inmunología , Subgrupos de Linfocitos B/inmunología , Dislipidemias/inmunología , Animales , Antígenos CD/sangre , Aorta/metabolismo , Aorta/patología , Enfermedades de la Aorta/sangre , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/patología , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Aterosclerosis/sangre , Aterosclerosis/genética , Aterosclerosis/patología , Subgrupos de Linfocitos B/metabolismo , Biomarcadores/sangre , Células Cultivadas , Quimiotaxis de Leucocito , Colesterol/sangre , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Dislipidemias/sangre , Dislipidemias/genética , Femenino , Citometría de Flujo , Predisposición Genética a la Enfermedad , Inmunoglobulina G/sangre , Inmunofenotipificación/métodos , Recuento de Linfocitos , Ratones Noqueados , FenotipoRESUMEN
Alzheimer's disease (AD) is the most common senile dementia in the world. Although important progress has been made in understanding the pathogenesis of AD, current therapeutic approaches provide only modest symptomatic relief. In this study, we evaluated the neuroprotective effect of quercetin (25 mg/kg) administration via i.p. injection every 48 h for 3 months on aged (21-24 months old) triple transgenic AD model (3xTg-AD) mice. Our data show that quercetin decreases extracellular ß-amyloidosis, tauopathy, astrogliosis and microgliosis in the hippocampus and the amygdala. These results were supported by a significant reduction in the paired helical filament (PHF), ß-amyloid (ßA) 1-40 and ßA 1-42 levels and a decrease in BACE1-mediated cleavage of APP (into CTFß). Additionally, quercetin induced improved performance on learning and spatial memory tasks and greater risk assessment behavior based on the elevated plus maze test. Together, these findings suggest that quercetin reverses histological hallmarks of AD and protects cognitive and emotional function in aged 3xTg-AD mice.
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Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Antioxidantes/uso terapéutico , Encéfalo/patología , Trastornos del Conocimiento/prevención & control , Trastornos del Humor/prevención & control , Quercetina/uso terapéutico , Envejecimiento , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Trastornos del Conocimiento/etiología , Modelos Animales de Enfermedad , Esquema de Medicación , Gliosis/etiología , Gliosis/prevención & control , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Transgénicos , Trastornos del Humor/etiología , Proteínas del Tejido Nervioso/metabolismo , Neuroglía/patología , Presenilina-1/genética , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/genética , Proteínas tau/genéticaRESUMEN
Pentacyclic triterpene Natural product Cytokine modulation Anti-inflammatory activity Dendritic cells Pentacyclic triterpenes are a large family of plant metabolites that exhibit a wide array of biological activities. The genus Cecropia, which encompasses many plant species, has been used as traditional medicine for the treatment of inflammatory diseases and is known to produce many active pentacyclic triterpenes. In this study we investigated the chemical composition of a pentacyclic triterpene fraction from the roots of Cecropia telenitida Cuatrec., Urticaceae. A novel compound, which we termed yarumic acid, and four known molecules (serjanic acid, spergulagenic acid A, 20-hydroxy-ursolic acid and goreishic acid I) were isolated and characterised. In a dendritic cell (DC)based assay, we demonstrated that non-toxic doses of these pentacyclic triterpenes inhibited the secretion of at least one of the proinflammatory cytokines tested (IL-1β, IL-12p40, IL-12p70, TNF-α). Spergulagenic acid A also inhibited nitric oxide production in lipopolysaccharide-stimulated dendritic cell. Serjanic acid and spergulagenic acid A, which were the most potent abundant compounds in the pentacyclic triterpene fraction, showed the most activity in the dendritic cell-based assay. These results show that all pentacyclic triterpenes might contribute to the anti-inflammatory activities of C. telenitida. Moreover, yarumic acid as well as the four known pentacyclic triterpenes, can be exploited as potential immunomodulatory/anti-inflammatory agents.
RESUMEN
Many studies have demonstrated that the flavonoid quercetin protects against cardiovascular disease (CVD) and related risk factors. Atherosclerosis, the underlying cause of CVD, is also attenuated by oral quercetin administration in animal models. Although macrophages are key players during fatty streak formation and plaque progression and aggravation, little is known about the effects of quercetin on atherogenic macrophages. Here, we report that primary bone marrow-derived macrophages internalized less oxidized low-density lipoprotein (oxLDL) and accumulated less intracellular cholesterol in the presence of quercetin. This reduction of foam cell formation correlated with reduced surface expression of the oxLDL receptor CD36. Quercetin also targeted the lipopolysaccharide-dependent, oxLDL-independent pathway of lipid droplet formation in macrophages. In oxLDL-stimulated macrophages, quercetin inhibited reactive oxygen species production and interleukin (IL)-6 secretion. In a system that evaluated cholesterol crystal-induced IL-1ß secretion via nucleotide-binding domain and leucine-rich repeat containing protein 3 inflammasome activation, quercetin also exhibited an inhibitory effect. Dyslipidemic apolipoprotein E-deficient mice chronically treated with intraperitoneal quercetin injections had smaller atheromatous lesions, reduced lipid deposition, and less macrophage and T cell inflammatory infiltrate in the aortic roots than vehicle-treated animals. Serum levels of total cholesterol and the lipid peroxidation product malondialdehyde were also reduced in these mice. Our results demonstrate that quercetin interferes with both key proatherogenic activities of macrophages, namely foam cell formation and pro-oxidant/proinflammatory responses, and these effects may explain the atheroprotective properties of this common flavonoid.
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Antioxidantes/farmacología , Aterosclerosis/patología , Aterosclerosis/prevención & control , Macrófagos/patología , Quercetina/farmacología , Animales , Apolipoproteínas E/genética , Antígenos CD36/biosíntesis , Antígenos CD36/genética , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Citocinas/metabolismo , Dieta , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Células Espumosas/metabolismo , Humanos , Inflamación/patología , Metabolismo de los Lípidos/genética , Metabolismo de los Lípidos/fisiología , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Healthy Colombian adult volunteers with no history of leishmaniasis were evaluated for evidence of previous subclinical infection with Leishmania based on the Montenegro skin test (MST). Twelve MST-positive subjects were enrolled in an open-label, uncontrolled clinical trial (the "MST-positive trial") and received three injections of the LEISH-F1+MPL-SE vaccine (consisting of 10 microg recombinant Leishmania polyprotein LEISH-F1 antigen [TSA+LmSTI1+LeIF]+25 microg MPL-SE adjuvant). Sixty-eight MST-negative subjects were enrolled in a randomized, double-blind, controlled trial (the "MST-negative trial") and were randomly assigned to receive three injections of either the vaccine (n=34), 10 microg LEISH-F1 protein alone (n=17), or saline placebo (n=17). In both trials, the study injections were given subcutaneously on Days 0, 28, and 56, and subjects were followed for safety and immunological endpoints. The LEISH-F1+MPL-SE vaccine was safe and well tolerated in MST-positive and MST-negative subjects. In both trials, an IFN-gamma response to the LEISH-F1 antigen at Day 84 was observed in more than half of the vaccine recipients. In the MST-negative trial, the IFN-gamma response was significantly more frequent and of greater magnitude in vaccine recipients than in protein-alone or placebo recipients. An IgG antibody response to LEISH-F1 was observed in all vaccine recipients. In both trials, delayed-type hypersensitivity (DTH) to LEISH-F1 was observed in most of the vaccine recipients. In the MST-negative trial, DTH was significantly higher in vaccine than placebo recipients. These clinical trials of the first defined vaccine for leishmaniasis show that the LEISH-F1+MPL-SE vaccine is safe and immunogenic in healthy subjects with and without evidence of previous subclinical infection with Leishmania.
Asunto(s)
Vacunas contra la Leishmaniasis/inmunología , Leishmaniasis Cutánea/inmunología , Leishmaniasis Cutánea/prevención & control , Adolescente , Adulto , Método Doble Ciego , Femenino , Humanos , Vacunas contra la Leishmaniasis/efectos adversos , Masculino , Adulto JovenRESUMEN
Through the action of glycosyltransferases, a plant can biosynthetically assemble small different aglycons or 'templates' to various polysaccharides to produce numerous glycoconjugates differing in the type of the attached aglycon, the anomeric configuration of C-1 of the glycosylating sugar, the type of sugar and the different position of attachments of the sugar unit present in the polysaccharide chain. The position of attachments and the anomeric configuration of the different sugar present in the polysaccharide create the opportunity to generate molecules with either the same or very close molecular weights, which have relative structural similarity--forming isobaric and positional isomers. Although isomeric differentiation was once considered outside of the domain of mass spectrometry, this task can now be resolved using tandem mass spectrometry. In a standardized purified glycoconjugate fraction (SPT01) from Phytolacca bogotensis, we report conventional electrospray ionization mass spectrometry and collision-induced dissociation (CID) MS/MS parameters which favored the formation of characteristic product ions. This allowed us to suggest the type of sugar linkages present in a specific glycoconjugate. Ten new glycoconjugate are described from this plant and another twelve known saponins were structurally characterized using the automatic MSn acquisition mode. The differentiation of two pairs of positional isomers and four isobaric glycosides and the production of a library of 30 glycosides present in P. bogotensis were accomplished.