RESUMEN
CD19-directed chimeric antigen receptor (CAR) T cells have yielded impressive response rates in refractory/relapse B cell acute lymphoblastic leukemia (B-ALL); however, most patients ultimately relapse due to poor CAR T cell persistence or resistance of either CD19+ or CD19- B-ALL clones. CD22 is a pan-B marker whose expression is maintained in both CD19+ and CD19- relapses. CD22-CAR T cells have been clinically used in B-ALL patients, although relapse also occurs. T cells engineered with a tandem CAR (Tan-CAR) containing in a single construct both CD19 and CD22 scFvs may be advantageous in achieving higher remission rates and/or preventing antigen loss. We have generated and functionally validated using cutting-edge assays a 4-1BB-based CD22/CD19 Tan-CAR using in-house-developed novel CD19 and CD22 scFvs. Tan-CAR-expressing T cells showed similar in vitro expansion to CD19-CAR T cells with no increase in tonic signaling. CRISPR-Cas9-edited B-ALL cells confirmed the bispecificity of the Tan-CAR. Tan-CAR was as efficient as CD19-CAR in vitro and in vivo using B-ALL cell lines, patient samples, and patient-derived xenografts (PDXs). Strikingly, the robust antileukemic activity of the Tan-CAR was slightly more effective in controlling the disease in long-term follow-up PDX models. This Tan-CAR construct warrants a clinical appraisal to test whether simultaneous targeting of CD19 and CD22 enhances leukemia eradication and reduces/delays relapse rates and antigen loss.
Asunto(s)
Receptores Quiméricos de Antígenos , Antígenos CD19 , Linfocitos B , Humanos , Inmunoterapia Adoptiva , Receptores Quiméricos de Antígenos/metabolismo , Lectina 2 Similar a Ig de Unión al Ácido Siálico/genética , Linfocitos TRESUMEN
INTRODUCTION: Previously, we found that intracellular calcium (Ca2+) homeostasis is altered in platelets from an experimental model of liver cirrhosis, namely the bile-duct-ligated (BDL) rat. These alterations are compatible with the existence of a hypercoagulable state. OBJECTIVE: In the present study, we analyzed the role of nitric oxide in the abnormal calcium signaling responses of an experimental cirrhosis model, the bile duct-ligated rat. METHODS: Chronic treatment with L-NAME was used to inhibit NO production in a group of control and BDL animals, and the responses compared to those obtained in a control and BDL untreated group (n = 6 each). The experiments were conducted on isolated platelets loaded with fura-2, using fluorescence spectrometry. RESULTS: Chronic treatment with L-NAME increased thrombin-induced Ca2+ release from internal stores in both control and BDL rats. However, the effect was significantly greater in the BDL rats (p < 0.05). Thrombin-induced calcium entry from the extracellular space was also elevated but at lower doses and, similarly in both control and BDL platelets, treated with the NO synthesis inhibitor. Capacitative calcium entry was also enhanced in the control platelets but not in platelets from BDL rats treated with L-NAME. Total calcium in intracellular stores was elevated in untreated platelets from BDL rats, and L-NAME pretreatment significantly (p < 0.05) elevated these values both in controls and in BDL but significantly more in the BDL rats (p < 0.05). CONCLUSIONS: Our results suggest that nitric oxide plays a role in the abnormal calcium signaling responses observed in platelets from BDL rats by interfering with the mechanism that releases calcium from the internal stores.
Asunto(s)
Cirrosis Hepática Biliar , Ratas , Animales , Óxido Nítrico/uso terapéutico , Plaquetas , Calcio , Ratas Sprague-Dawley , NG-Nitroarginina Metil Éster/farmacología , Trombina/farmacología , Trombina/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , LigaduraRESUMEN
Previously, we have found that intracellular calcium homeostasis is altered in platelets from an experimental model of liver cirrhosis, the bile-duct ligated (BDL) rat; these alterations are compatible with the existence of a hypercoagulable state. Different studies indicate that cholestatic diseases are associated with hyperhomocysteinemia; thus, we hypothetized that it could contribute to those platelet alterations. In the present study, we have investigated the role of homocysteine (HCY) in platelet aggregation and calcium signaling in the BDL model. The effect of chronic folic acid treatment was also analyzed. Acute treatment with HCY increased the aggregation response to ADP and calcium responses to thrombin in platelets of control and BDL rats. Capacitative calcium entry was not altered by HCY. Chronic treatment with folic acid decreased platelet aggregation in control and BDL rats, but this decrease was greater in BDL rats. In folic acid-treated rats, thrombin-induced calcium entry and release were decreased in platelet of control rats but unaltered in BDL rats; however, capacitative calcium entry was decreased in platelets of control and BDL rats treated with folic acid. Reactive oxygen species were produced at higher levels by BDL platelets after stimulation with HCY or thrombin and folic acid normalized these responses. HCY plays a role in the enhanced platelet aggregation response of BDL rats, probably through an enhanced formation of ROS. Folic acid pretreatment normalizes many of the platelet alterations shown by BDL rats.
Asunto(s)
Calcio/metabolismo , Colestasis/sangre , Ácido Fólico/farmacología , Homocisteína/farmacología , Cirrosis Hepática Biliar/sangre , Agregación Plaquetaria/efectos de los fármacos , Adenosina Difosfato/farmacología , Administración Oral , Animales , Conductos Biliares/cirugía , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Plaquetas/patología , Señalización del Calcio , Colestasis/patología , Modelos Animales de Enfermedad , Homocisteína/antagonistas & inhibidores , Ligadura , Cirrosis Hepática Biliar/patología , Masculino , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Trombina/farmacologíaRESUMEN
Tissue regeneration requires the activation of a set of specific growth signaling pathways. The identity of these cascades and their biological roles are known; however, the molecular mechanisms regulating the interplay between these pathways remain poorly understood. Here, we define a new role for SULFATASE 2 (SULF2) in regulating tissue regeneration and define the WNT-GLI1 axis as a novel downstream effector for this sulfatase in a liver model of tissue regeneration. SULF2 is a heparan sulfate 6-O-endosulfatase, which releases growth factors from extracellular storage sites turning active multiple signaling pathways. We demonstrate that SULF2-KO mice display delayed regeneration after partial hepatectomy (PH). Mechanistic analysis of the SULF2-KO phenotype showed a decrease in WNT signaling pathway activity in vivo. In isolated hepatocytes, SULF2 deficiency blocked WNT-induced ß-CATENIN nuclear translocation, TCF activation, and proliferation. Furthermore, we identified the transcription factor GLI1 as a novel target of the SULF2-WNT cascade. WNT induces GLI1 expression in a SULF2- and ß-CATENIN-dependent manner. GLI1-KO mice phenocopied the SULF2-KO, showing delayed regeneration and decreased hepatocyte proliferation. Moreover, we identified CYCLIN D1, a key mediator of cell growth during tissue regeneration, as a GLI1 transcriptional target. GLI1 binds to the cyclin d1 promoter and regulates its activity and expression. Finally, restoring GLI1 expression in the liver of SULF2-KO mice after PH rescues CYCLIN D1 expression and hepatocyte proliferation to wild-type levels. Thus, together these findings define a novel pathway in which SULF2 regulates tissue regeneration in part via the activation of a novel WNT-GLI1-CYCLIN D1 pathway.
Asunto(s)
Factores de Transcripción de Tipo Kruppel/metabolismo , Regeneración Hepática , Sulfatasas/metabolismo , Vía de Señalización Wnt , Animales , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Proteínas Hedgehog/metabolismo , Hepatectomía , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Regeneración Hepática/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Sulfatasas/deficiencia , Vía de Señalización Wnt/efectos de los fármacos , Proteína Wnt3A/farmacología , Proteína con Dedos de Zinc GLI1 , beta Catenina/metabolismoRESUMEN
Relapse remains a major challenge in the clinical management of acute myeloid leukemia (AML) and is driven by rare therapy-resistant leukemia stem cells (LSCs) that reside in specific bone marrow niches. Hypoxia signaling maintains cells in a quiescent and metabolically relaxed state, desensitizing them to chemotherapy. This suggests the hypothesis that hypoxia contributes to the chemoresistance of AML-LSCs and may represent a therapeutic target to sensitize AML-LSCs to chemotherapy. Here, we identify HIFhigh and HIFlow specific AML subgroups (inv(16)/t(8;21) and MLLr, respectively) and provide a comprehensive single-cell expression atlas of 119,000 AML cells and AML-LSCs in paired diagnostic-relapse samples from these molecular subgroups. The HIF/hypoxia pathway signature is attenuated in AML-LSCs compared with more differentiated AML cells but is more expressed than in healthy hematopoietic cells. Importantly, chemical inhibition of HIF cooperates with standard-of-care chemotherapy to impair AML growth and to substantially eliminate AML-LSCs in vitro and in vivo. These findings support the HIF pathway in the stem cell-driven drug resistance of AML and unravel avenues for combinatorial targeted and chemotherapy-based approaches to specifically eliminate AML-LSCs.
RESUMEN
Osteosarcoma (OS) remains a dismal malignancy in children and young adults, with poor outcome for metastatic and recurrent disease. Immunotherapies in OS are not as promising as in some other cancer types due to intra-tumor heterogeneity and considerable off-target expression of the potentially targetable proteins. Here we show that chimeric antigen receptor (CAR) T cells could successfully target an isoform of alkaline phosphatase, ALPL-1, which is highly and specifically expressed in primary and metastatic OS. The target recognition element of the second-generation CAR construct is based on two antibodies, previously shown to react against OS. T cells transduced with these CAR constructs mediate efficient and effective cytotoxicity against ALPL-positive cells in in vitro settings and in state-of-the-art in vivo orthotopic models of primary and metastatic OS, without unexpected toxicities against hematopoietic stem cells or healthy tissues. In summary, CAR-T cells targeting ALPL-1 show efficiency and specificity in treating OS in preclinical models, paving the path for clinical translation.
Asunto(s)
Neoplasias Óseas , Osteosarcoma , Niño , Humanos , Inmunoterapia Adoptiva , Linfocitos T , Inmunoterapia , Osteosarcoma/terapia , Neoplasias Óseas/terapia , Línea Celular Tumoral , Fosfatasa AlcalinaRESUMEN
Leukemia stem cells (LSCs) share numerous features with healthy hematopoietic stem cells (HSCs). G-protein coupled receptor family C group 5 member C (GPRC5C) is a regulator of HSC dormancy. However, GPRC5C functionality in acute myeloid leukemia (AML) is yet to be determined. Within patient AML cohorts, high GPRC5C levels correlated with poorer survival. Ectopic Gprc5c expression increased AML aggression through the activation of NF-κB, which resulted in an altered metabolic state with increased levels of intracellular branched-chain amino acids (BCAAs). This onco-metabolic profile was reversed upon loss of Gprc5c, which also abrogated the leukemia-initiating potential. Targeting the BCAA transporter SLC7A5 with JPH203 inhibited oxidative phosphorylation and elicited strong antileukemia effects, specifically in mouse and patient AML samples while sparing healthy bone marrow cells. This antileukemia effect was strengthened in the presence of venetoclax and azacitidine. Our results indicate that the GPRC5C-NF-κB-SLC7A5-BCAAs axis is a therapeutic target that can compromise leukemia stem cell function in AML.
Asunto(s)
Aminoácidos de Cadena Ramificada , Leucemia Mieloide Aguda , Receptores Acoplados a Proteínas G , Animales , Humanos , Ratones , Aminoácidos de Cadena Ramificada/uso terapéutico , Transportador de Aminoácidos Neutros Grandes 1/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , FN-kappa B/metabolismo , Receptores Acoplados a Proteínas G/metabolismoRESUMEN
Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer, with survival rates exceeding 85%. However, 15% of patients will relapse; consequently, their survival rates decrease to below 50%. Therefore, several research and innovation studies are focusing on pediatric relapsed or refractory ALL (R/R ALL). Driven by this context and following the European strategic plan to implement precision medicine equitably, the Relapsed ALL Network (ReALLNet) was launched under the umbrella of SEHOP in 2021, aiming to connect bedside patient care with expert groups in R/R ALL in an interdisciplinary and multicentric network. To achieve this objective, a board consisting of experts in diagnosis, management, preclinical research, and clinical trials has been established. The requirements of treatment centers have been evaluated, and the available oncogenomic and functional study resources have been assessed and organized. A shipping platform has been developed to process samples requiring study derivation, and an integrated diagnostic committee has been established to report results. These biological data, as well as patient outcomes, are collected in a national registry. Additionally, samples from all patients are stored in a biobank. This comprehensive repository of data and samples is expected to foster an environment where preclinical researchers and data scientists can seek to meet the complex needs of this challenging population. This proof of concept aims to demonstrate that a network-based organization, such as that embodied by ReALLNet, provides the ideal niche for the equitable and efficient implementation of "what's next" in the management of children with R/R ALL.
RESUMEN
Flavonoids are a class of substances of a vegetal origin with many interesting actions from the point of view of human disease. Interest in flavonoids in the diet has increased in recent years due to the publication of basic, clinical and epidemiological studies that have shown a whole array of salutary effects related to intake of flavonols and flavones as well as a lower morbility and mortality of cardiovascular diseases. Since arterial hypertension is the most common modifiable risk factor for cardiovascular diseases, this review will focus mainly on the effects of flavonoids on the cardiovascular system with relation to the elevation of blood pressure. Its antihypertensive effects as well as the many investigations performed in experimental models of arterial hypertension, are reviewed in this mini-review.
Asunto(s)
Enfermedades Cardiovasculares , Hipertensión , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Flavonoides/farmacología , Flavonoides/uso terapéutico , Humanos , Hipertensión/tratamiento farmacológico , Modelos TeóricosRESUMEN
BACKGROUND: Chimeric antigen receptor (CAR)-T cells have emerged as a breakthrough treatment for relapse/refractory hematological tumors, showing impressive complete remission rates. However, around 50% of the patients relapse before 1-year post-treatment. T-cell 'fitness' is critical to prolong CAR-T persistence and activity. Allogeneic T cells from healthy donors are less dysfunctional or exhausted than autologous patient-derived T cells; in this context, Delta One T cells (DOTs), a recently described cellular product based on MHC/HLA-independent Vδ1+γδ T cells, represent a promising allogeneic platform. METHODS: Here we generated and preclinically validated, for the first time, 4-1BB-based CAR-DOTs directed against the interleukin-3α chain receptor (CD123), a target antigen widely expressed on acute myeloid leukemia (AML) blasts. RESULTS: CD123CAR-DOTs showed vigorous, superior to control DOTs, cytotoxicity against AML cell lines and primary samples both in vitro and in vivo, even on tumor rechallenge. CONCLUSIONS: Our results provide the proof-of-concept for a DOT-based next-generation allogeneic CAR-T therapy for AML.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Receptores Quiméricos de Antígenos , Línea Celular Tumoral , Humanos , Subunidad alfa del Receptor de Interleucina-3/metabolismo , Interleucinas , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/terapia , RecurrenciaRESUMEN
Mesenchymal stromal stem/cells (MSC) therapies are clinically used in a wide range of disorders based on their robust HLA-independent immunosuppressive and anti-inflammatory properties. However, the mechanisms underlying MSC therapeutic activity remain elusive as demonstrated by the unpredictable therapeutic efficacy of MSC infusions reported in multiple clinical trials. A seminal recent study showed that infused MSCs are actively induced to undergo apoptosis by recipient cytotoxic T cells, a mechanism that triggers in vivo recipient-induced immunomodulation by such apoptotic MSCs, and the need for such recipient cytotoxic cell activity could be replaced by the administration of ex vivo-generated apoptotic MSCs. Moreover, the use of MSC-derived extracellular vesicles (MSC-EVs) is being actively explored as a cell-free therapeutic alternative over the parental MSCs. We hypothesized that the introduction of a "suicide gene" switch into MSCs may offer on-demand in vivo apoptosis of transplanted MSCs. Here, we prompted to investigate the utility of the iCasp9/AP1903 suicide gene system in inducing apoptosis of MSCs. iCasp9/AP1903-induced apoptotic MSCs (MSCiCasp9+) were tested in vitro and in in vivo models of acute colitis. Our data show a very similar and robust immunosuppressive and anti-inflammatory properties of both "parental" alive MSCGFP+ cells and apoptotic MSCiCasp9+ cells in vitro and in vivo regardless of whether apoptosis was induced in vivo or in vitro before administering MSCiCasp9+ lysates. This development of an efficient iCasp9 switch may potentiate the safety of MSC-based therapies in the case of an adverse event and, will also circumvent current logistic technical limitations and biological uncertainties associated to MSC-EVs.
Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Antiinflamatorios , Caspasa 9 , Vesículas Extracelulares/trasplante , Humanos , Inmunomodulación , InmunosupresoresRESUMEN
Acute myeloid leukemia (AML) is the most common acute leukemia in adults. Patients with AML harboring a constitutively active internal tandem duplication mutation (ITDMUT) in the FMS-like kinase tyrosine kinase (FLT3) receptor generally have a poor prognosis. Several tyrosine kinase/FLT3 inhibitors have been developed and tested clinically, but very few (midostaurin and gilteritinib) have thus far been FDA/EMA-approved for patients with newly diagnosed or relapse/refractory FLT3-ITDMUT AML. Disappointingly, clinical responses are commonly partial or not durable, highlighting the need for new molecules targeting FLT3-ITDMUT AML. Here, we tested EC-70124, a hybrid indolocarbazole analog from the same chemical space as midostaurin with a potent and selective inhibitory effect on FLT3. In vitro, EC-70124 exerted a robust and specific antileukemia activity against FLT3-ITDMUT AML primary cells and cell lines with respect to cytotoxicity, CFU capacity, apoptosis and cell cycle while sparing healthy hematopoietic (stem/progenitor) cells. We also analyzed its efficacy in vivo as monotherapy using two different xenograft models: an aggressive and systemic model based on MOLM-13 cells and a patient-derived xenograft model. Orally disposable EC-70124 exerted a potent inhibitory effect on the growth of FLT3-ITDMUT AML cells, delaying disease progression and debulking the leukemia. Collectively, our findings show that EC-70124 is a promising and safe agent for the treatment of AML with FLT3-ITDMUT.
RESUMEN
CD19-directed chimeric antigen receptors (CAR) T cells induce impressive rates of complete response in advanced B-cell malignancies, specially in B-cell acute lymphoblastic leukemia (B-ALL). However, CAR T-cell-treated patients eventually progress due to poor CAR T-cell persistence and/or disease relapse. The bone marrow (BM) is the primary location for acute leukemia. The rapid/efficient colonization of the BM by systemically infused CD19-CAR T cells might enhance CAR T-cell activity and persistence, thus, offering clinical benefits. Circulating cells traffic to BM upon binding of tetrasaccharide sialyl-Lewis X (sLeX)-decorated E-selectin ligands (sialofucosylated) to the E-selectin receptor expressed in the vascular endothelium. sLeX-installation in E-selectin ligands is achieved through an ex vivo fucosylation reaction. Here, we sought to characterize the basal and cell-autonomous display of sLeX in CAR T-cells activated using different cytokines, and to assess whether exofucosylation of E-selectin ligands improves CD19-CAR T-cell activity and BM homing. We report that cell-autonomous sialofucosylation (sLeX display) steadily increases in culture- and in vivo-expanded CAR T cells, and that, the cytokines used during T-cell activation influence both the degree of such endogenous sialofucosylation and the CD19-CAR T-cell efficacy and persistence in vivo. However, glycoengineered enforced sialofucosylation of E-selectin ligands was dispensable for CD19-CAR T-cell activity and BM homing in multiple xenograft models regardless the cytokines employed for T-cell expansion, thus, representing a dispensable strategy for CD19-CAR T-cell therapy.
Asunto(s)
Antígenos CD19/inmunología , Médula Ósea/inmunología , Selectina E/inmunología , Inmunoterapia Adoptiva/métodos , Receptores Quiméricos de Antígenos/inmunología , Antígeno Sialil Lewis X/inmunología , Animales , Endotelio Vascular/inmunología , Ligandos , Ratones , Ratones Endogámicos NOD , Modelos AnimalesRESUMEN
Our results do not support any effect of FVIII on platelet function in patients with severe HA treated under the regime of prophylaxis.
RESUMEN
BACKGROUND: Although adoptive transfer of CD19-directed chimeric antigen receptor (CAR) T-cells (CD19-CAR T-cells) achieves high rates of complete response in patients with B-cell acute lymphoblastic leukemia (B-ALL), relapse is common. Bone marrow (BM) mesenchymal stem/stromal cells (BM-MSC) are key components of the hematopoietic niche and are implicated in B-ALL pathogenesis and therapy resistance. MSC exert an immunosuppressive effect on T-cells; however, their impact on CD19-CAR T-cell activity is understudied. METHODS: We performed a detailed characterization of BM-MSC from pediatric patients with B-ALL (B-ALL BM-MSC), evaluated their immunomodulatory properties and their impact on CD19-CAR T-cell activity in vitro using microscopy, qRT-PCR, ELISA, flow cytometry analysis and in vivo using a preclinical model of severe colitis and a B-ALL xenograft model. RESULTS: While B-ALL BM-MSC were less proliferative than those from age-matched healthy donors (HD), the morphology, immunophenotype, differentiation potential and chemoprotection was very similar. Likewise, both BM-MSC populations were equally immunosuppressive in vitro and anti-inflammatory in an in vivo model of severe colitis. Interestingly, BM-MSC failed to impair CD19-CAR T-cell cytotoxicity or cytokine production in vitro using B-ALL cell lines and primary B-ALL cells. Finally, the growth of NALM6 cells was controlled in vivo by CD19-CAR T-cells irrespective of the absence/presence of BM-MSC. CONCLUSIONS: Collectively, our data demonstrate that pediatric B-ALL and HD BM-MSC equally immunosuppress T-cell responses but do not compromise CD19-CAR T-cell activity.
Asunto(s)
Antígenos CD19/inmunología , Médula Ósea/inmunología , Terapia de Inmunosupresión/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , Animales , Femenino , Humanos , Masculino , Ratones , Microambiente TumoralRESUMEN
BACKGROUND: The treatment of extensive and/or chronic skin wounds is a widespread and costly public health problem. Mesenchymal stem cells (MSCs) have been proposed as a potential cell therapy for inducing wound healing in different clinical settings, alone or in combination with biosynthetic scaffolds. Among them, silk fibroin (SF) seeded with MSCs has been shown to have increased efficacy in skin wound healing experimental models. METHODS: In this report, we investigated the wound healing effects of electrospun SF scaffolds cellularized with human Wharton's jelly MSCs (Wj-MSCs-SF) using a murine excisional wound splinting model. RESULTS: Immunohistopathological examination after transplant confirmed the presence of infiltrated human fibroblast-like CD90-positive cells in the dermis of the Wj-MSCs-SF-treated group, yielding neoangiogenesis, decreased inflammatory infiltrate and myofibroblast proliferation, less collagen matrix production, and complete epidermal regeneration. CONCLUSIONS: These findings indicate that Wj-MSCs transplanted in the wound bed on a silk fibroin scaffold contribute to the generation of a well-organized and vascularized granulation tissue, enhance reepithelization of the wound, and reduce the formation of fibrotic scar tissue, highlighting the potential therapeutic effects of Wj-MSC-based tissue engineering approaches to non-healing wound treatment.
Asunto(s)
Cicatriz/terapia , Fibroínas/farmacología , Andamios del Tejido , Gelatina de Wharton/metabolismo , Animales , Cicatriz/patología , Fibroblastos/metabolismo , Humanos , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Repitelización/efectos de los fármacos , Piel/efectos de los fármacos , Piel/lesiones , Piel/patología , Ingeniería de Tejidos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
BACKGROUND: we have evaluated the antihypertensive effect of several flavonoid extracts in a rat model of arterial hypertension caused by chronic administration (6 weeks) of the nitric oxide synthesis inhibitor, L-NAME. METHODS: Sprague Dawley rats received L-NAME alone or L-NAME plus flavonoid-rich vegetal extracts (Lemon, Grapefruit + Bitter Orange, and Cocoa) or purified flavonoids (Apigenin and Diosmin) for 6 weeks. RESULTS: L-NAME treatment resulted in a marked elevation of blood pressure, and treatment with Apigenin, Lemon Extract, and Grapefruit + Bitter Orange extracts significantly reduced the elevated blood pressure of these animals. Apigenin and some of these flavonoids also ameliorated nitric oxide-dependent and -independent aortic vasodilation and elevated nitrite urinary excretion. End-organ abnormalities such as cardiac infarcts, hyaline arteriopathy and fibrinoid necrosis in coronary arteries and aorta were improved by these treatments, reducing the end-organ vascular damage. CONCLUSIONS: the flavonoids included in this study, specially apigenin, may be used as functional food ingredients with potential therapeutic benefit in arterial hypertension.
Asunto(s)
Antihipertensivos/uso terapéutico , Flavonoides/uso terapéutico , Hipertensión/inducido químicamente , Riñón/fisiología , NG-Nitroarginina Metil Éster/toxicidad , Extractos Vegetales/uso terapéutico , Animales , Antihipertensivos/química , Apigenina/administración & dosificación , Apigenina/uso terapéutico , Hipertensión/tratamiento farmacológico , Masculino , Extractos Vegetales/química , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
Many studies have shown that flavonoids are effective as antihypertensive drugs in arterial hypertension. In the present work, we have analyzed the effects of some flavonoid extracts in the spontaneous hypertensive rat model (SHR). An important feature of this study is that we have used a low dose, far from those that are usually applied in human therapy or experimental animals, a dose that responded to the criterion of a potential future commercial use in human subjects. Treatments were carried out for 6 and 12 weeks in two groups of SHR rats, which received apigenin, lemon extract, grapefruit + bitter orange (GBO) extracts, and cocoa extract. Captopril was used as a positive control in the SHR group treated for 6 weeks (SHR6) and Diosmin was used as the industry reference in the SHR group treated for 12 weeks (SHR12). Captopril and GBO extracts lowered the high arterial pressure of the SHR6 animals, but none of the extracts were effective in the SHR12 group. Apigenin, lemon extract (LE), GBO, and captopril also improved aortic vascular relaxation and increased plasma and urinary excretion of nitrites, but only in the SHR6 group. Kidney and urinary thiobarbituric acid reactive substances (TBARS) were also significantly reduced by GBO in the SHR6 rats. Apigenin also improved vascular relaxation in the SHR12 group and all the flavonoids studied reduced urinary thiobarbituric acid reactive substances (TBARS) excretion and proteinuria. Vascular abnormalities, such as lumen/wall ratio in heart arteries and thoracic aorta, were moderately improved by these treatments in the SHR6 group. In conclusion, the flavonoid-rich extracts included in this study, especially apigenin, LE and GBO improved vascular vasodilatory function of young adult SHRs but only the GBO-treated rats benefited from a reduction in blood pressure. These extracts may be used as functional food ingredients with a moderate therapeutic benefit, especially in the early phases of arterial hypertension.