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1.
Ann Hematol ; 103(4): 1353-1362, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38430226

RESUMEN

During hematopoietic stem cell transplantation (HSCT), ATG depletes T cells in-vivo to improve engraftment and prevent graft-versus-host disease (GVHD). Here, we compared the clinical efficacy of two different types of ATGs: thymoglobulin and anti-human T-lymphocyte immunoglobulin (Grafalon). A total of 469 patients who received haploidentical transplantation were enrolled in this retrospective study. We applied a propensity score (PS)-matched analysis and 209 patients were assigned to each group. Clinical outcomes were compared between two groups and primary outcome was overall survival (OS). There was no significant difference in OS between two groups. Within the first 180 days after HSCT, Grafalon was associated with lower incidences of Epstein-Barr virus (EBV) viremia (31.6 vs. 54.5%, P < 0.0001) and cytomegalovirus viremia (CMV) viremia (54.5 vs. 67.9%, P = 0.005) compared to thymoglobulin. Patients receiving Grafalon had a higher rate of moderate/severe chronic GVHD (26.3 vs. 18.2%, P = 0.046). However, the incidences of engraftment failure, grade II-IV acute GVHD, relapse, non-relapse mortality (NRM), and GVHD-free relapse-free survival (GRFS) did not differ greatly between groups. In the subgroup analysis, Grafalon improved the OS of lymphoid malignancies with young ages (< 40 years old) (HR, 0.55; P = 0.04) or with a high/very high disease risk index (HR, 0.36; P = 0.04). In the myeloid cohort, Grafalon reduced NRM in the patients who received non-female for male transplantation grafts (HR, 0.17; P = 0.02). Our results suggest the two types of ATG may differentially influence transplant outcomes and it may optimize ATG selection according to the condition of patients.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Trasplante de Células Madre de Sangre Periférica , Animales , Conejos , Humanos , Masculino , Adulto , Estudios Retrospectivos , Puntaje de Propensión , Viremia , Herpesvirus Humano 4 , Suero Antilinfocítico , Trasplante de Células Madre Hematopoyéticas/métodos , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Acondicionamiento Pretrasplante/métodos
2.
Front Immunol ; 14: 1211221, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37457701

RESUMEN

Cellular metabolism plays a critical role in determining the fate and function of cells. Metabolic reprogramming and its byproducts have a complex impact on cellular activities. In quiescent T cells, oxidative phosphorylation (OXPHOS) is the primary pathway for survival. However, upon antigen activation, T cells undergo rapid metabolic reprogramming, characterized by an elevation in both glycolysis and OXPHOS. While both pathways are induced, the balance predominantly shifts towards glycolysis, enabling T cells to rapidly proliferate and enhance their functionality, representing the most distinctive signature during activation. Metabolic processes generate various small molecules resulting from enzyme-catalyzed reactions, which also modulate protein function and exert regulatory control. Notably, recent studies have revealed the direct modification of histones, known as lactylation, by lactate derived from glycolysis. This lactylation process influences gene transcription and adds a novel variable to the regulation of gene expression. Protein lactylation has been identified as an essential mechanism by which lactate exerts its diverse functions, contributing to crucial biological processes such as uterine remodeling, tumor proliferation, neural system regulation, and metabolic regulation. This review focuses on the metabolic reprogramming of T cells, explores the interplay between lactate and the immune system, highlights the impact of lactylation on cellular function, and elucidates the intersection of metabolic reprogramming and epigenetics.


Asunto(s)
Glucólisis , Histonas , Glucólisis/genética , Histonas/genética , Fosforilación Oxidativa , Lactatos , Procesamiento Proteico-Postraduccional
3.
Gut Microbes ; 15(1): 2221821, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37305973

RESUMEN

Despite significant achievements in hematopoietic stem cell transplantation (HSCT), graft-versus-host disease (GVHD), especially intestinal GVHD, remains a major obstacle to this procedure. GVHD has long been regarded as a pathogenic immune response, and the intestine has been simply considered as a target of immune attack. In effect, multiple factors contribute to intestinal damage after transplantation. Impaired intestinal homeostasis including altered intestinal microbiome and epithelial damage results in delayed wound healing, amplified immune response and sustained tissue destruction, and it may not fully recover following immunosuppression. In this review, we summarize factors leading to intestinal damage and discuss the relationship between intestinal damage and GVHD. We also describe the great potential of remodeling intestinal homeostasis in GVHD management.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Homeostasis , Terapia de Inmunosupresión
4.
J Transl Med ; 21(1): 329, 2023 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-37198603

RESUMEN

The success of allogeneic hematopoietic stem cell transplant for hematological malignancies is heavily dependent on the availability of suitable donors. Haploidentical donor (HID) and matched sibling donor (MSD) are two important donor options providing faster and easier sources of stem cells, however, due to confounding factors present in most retrospective studies, the validity of comparing outcomes between these two donor types remains uncertain. We conducted a post-hoc analysis of a prospective clinical trial (trial registration: Chinese Clinical Trial Registry; #ChiCTR-OCH-12002490; registered 22 February 2012; https://www.chictr.org.cn/showproj.aspx?proj=7061 ) to compare outcomes of HID versus MSD peripheral blood stem cell-derived transplants in patients with hematologic malignancies between 2015 and 2022. All HID-receiving patients had antithymocyte globulin-based conditioning. Propensity score matching was employed to minimize potential confounding factors between the two cohorts. A total of 1060 patients were initially reviewed and then 663 patients were ultimately included in the analysis after propensity score matching. The overall survival, relapse-free survival, non-relapse mortality rate and cumulative incidence of relapse were similar between HID and MSD cohorts. Subgroup analysis revealed that patients with positive measurable residual disease in first complete remission may have better overall survival with an HID transplant. The present demonstrated that haploidentical transplants can provide outcomes comparable to conventional MSD transplants, and HID should be recommended as one of the optimal donor choices for patients with positive measurable residual disease in first complete remission.


Asunto(s)
Enfermedad Injerto contra Huésped , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Humanos , Hermanos , Estudios Retrospectivos , Estudios Prospectivos , Puntaje de Propensión , Enfermedad Injerto contra Huésped/etiología , Recurrencia Local de Neoplasia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/complicaciones , Acondicionamiento Pretrasplante/efectos adversos
5.
Bone Marrow Transplant ; 58(8): 863-873, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37120616

RESUMEN

Relapse is a significant barrier to allogeneic hematopoietic stem cell transplantation (allo-HSCT) success. To explore the prognosis of patients who underwent relapse after allo-HSCT, we retrospectively examined 740 consecutive acute leukemia patients in our single center transplanted between January 2013 and December 2018, of which 178 relapsed. The median survival was 204 days (95%CI, 160.7-247.3) from relapse, and the 3-year post-relapse overall survival (prOS) rate was 17.8% (95%CI, 12.5-25.3%). Overall complete remission (CR) or CR with incomplete hematologic recovery (CRi) was achieved in 32.1% for the acute myeloid leukemia and 45.3% for acute lymphoblastic leukemia patients after salvage therapy, respectively. Grade III-IV acute graft-versus-host disease (GVHD) after transplantation and >20% bone marrow blasts at relapse were associated with worse prOS, while patients with chronic GVHD after transplantation, relapse later than 1 year after transplantation, and solitary extramedullary disease had better prOS. Therefore, we developed a concise risk scoring system for prOS based on the number of risk factors affecting prOS. This scoring system was validated with another cohort of post-transplant relapsed acute leukemia patients who received allo-HSCT between 2019 and 2020. Identifying relapse risk factors and providing personalized care for patients with poor prognoses is crucial for improving survival.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Humanos , Pronóstico , Estudios Retrospectivos , Leucemia Mieloide Aguda/complicaciones , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Enfermedad Aguda , Recurrencia
6.
JAMA Netw Open ; 5(4): e226114, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35385089

RESUMEN

Importance: Patient-specific human leukocyte antigen (HLA) genomic loss (HLA loss) is one of the reputed mechanisms of leukemia immune escape and relapse after haploidentical hematopoietic stem cell transplant (HSCT). However, clinical characteristics and prognosis of this distinct relapse type in the setting of haploidentical HSCT based on antithymocyte globulin (ATG) T-cell-replete conditioning are still unknown, especially for patients with lymphoid leukemia. Objective: To identify the incidence of and patient characteristics associated with HLA loss at hematologic cancer relapse after ATG-based haploidentical HSCT and to assess overall survival after HLA loss at relapse. Design, Setting, and Participants: This retrospective and multicenter case series study used data from medical records to identify patients who experienced relapse of hematologic cancer after receipt of ATG-based haploidentical HSCT. The study included 788 consecutive patients aged 8 to 70 years with lymphoid or myeloid leukemia who received ATG T-cell-replete haploidentical HSCT at the Zhejiang Cooperative Group for Blood and Marrow Transplantation between May 1, 2012, and May 31, 2021. Exposures: Relapse after ATG-based haploidentical HSCT. Main Outcomes and Measures: Incidence, risk factors, and postrelapse overall survival among patients with HLA loss at hematologic cancer relapse after receipt of haploidentical HSCT. Logistic regression analysis was used to identify characteristics associated with the likelihood of HLA loss, and Kaplan-Meier and Cox regression analyses were performed to evaluate postrelapse survival. Results: A total of 788 patients who received haploidentical HSCT for hematologic cancer were identified, 180 of whom experienced relapse after HSCT. Of those, 106 evaluable patients (median age, 30.9 years [range, 8.3-64.6 years]; 54 female [50.9%] and 52 male [49.1%]) were screened for HLA loss, which was detected in 54 patients (50.9%). Patients with HLA loss experienced relapse later than those without HLA loss (lymphoid group: median, 323 days [range, 98-2056 days] vs 151 days [range, 57-2544 days]; P = .01; myeloid group: median, 321 days [range, 55-1574 days] vs 223 days [range, 68-546 days]; P = .03). Among patients with lymphoid leukemia, those with minimal residual disease positivity before hematologic relapse (odds ratio [OR], 28.47; 95% CI, 1.99-407.98; P = .01), those with chronic graft-vs-host disease (OR, 27.68; 95% CI, 1.40-546.88; P = .03), and those with more than 180 days between HSCT and relapse (OR, 6.91; 95% CI, 1.32-36.22; P = .02) were more likely to lose unshared HLA at relapse, whereas male patients (OR, 0.03; 95% CI, 0.003-0.32; P = .04) were more likely to preserve their HLA genome at relapse. Patients with myeloid leukemia had different factors associated with HLA loss, including underweight status (OR, 0.10; 95% CI, 0.02-0.60; P = .01) and acute graft-vs-host disease (OR, 4.84; 95% CI, 1.14-20.53; P = .03). The receipt of preemptive donor lymphocyte infusion among patients with minimal residual disease recurrence did not postpone hematologic cancer relapse in those with HLA loss (median, 322 days [range, 204-1030 days]) compared with no receipt of donor lymphocyte infusion (median, 340 days [range, 215 days to not available]; P > .99). Conclusions and Relevance: In this study, HLA loss at leukemia relapse occurred frequently after receipt of ATG-based haploidentical HSCT. The identification of risk factors associated with HLA loss would help to prompt screening, avoid potentially harmful infusions of donor T cells, and develop alternative therapeutic strategies.


Asunto(s)
Enfermedad Injerto contra Huésped , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Leucemia , Adolescente , Adulto , Anciano , Suero Antilinfocítico/uso terapéutico , Niño , Femenino , Enfermedad Injerto contra Huésped/prevención & control , Antígenos HLA/genética , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia/etiología , Masculino , Persona de Mediana Edad , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/etiología , Recurrencia , Estudios Retrospectivos , Linfocitos T , Adulto Joven
7.
Am J Cancer Res ; 11(6): 3111-3122, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34249448

RESUMEN

Loss of patient-specific HLA after haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is considered as a relapse mechanism for lacking the incompatible molecule to elicit alloreactivity, which extensively diminishing graft-versus-leukemia (GVL) effects. Blinatumomab, as a CD3/CD19 bispecific antibody, can yield a profound response via redirecting T cells towards malignant lymphoblasts in B-cell acute lymphoblastic leukemia (B-ALL). We aimed to assess the feasibility of blinatumomab in treating patients with HLA loss relapse after haplo-HSCT. Four eligible patients undergoing HLA loss relapse after haplo-HSCT were enrolled in the study. Four patients achieved a complete remission/complete remission with partial he-matologic recovery (CR/CRh) with three minimal residual disease (MRD)-negative response within the first cycle of treatment. Three of the four met a primary endpoint with CR/CRh and MRD-negative response within 2 cycles of treatment. One patient developed new extramedullary sites of skin after the first cycle. Cytokine release syndrome was observed in one patient. Cytopenias, as well as elevated alanine aminotransferase and aspartate aminotransferase, were two common adverse effects during treatment. By redirecting lysis of CD19-positive lymphoblast who losing the incompatible HLA, blinatumomab is a potential strategy to eradicate malignant cells via restoring GVL effects. A randomized clinical trial assessing blinatumomab in patients with HLA loss relapse after HSCT is warranted.

8.
JAMA Netw Open ; 4(1): e2034750, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33502484

RESUMEN

Importance: Ruxolitinib, a selective inhibitor of the Janus kinases 1/2 signaling pathway, has shown a significant response in steroid-refractory chronic graft-vs-host disease (SR-cGVHD), a major cause of morbidity and mortality in individuals who have undergone allogeneic hematopoietic stem cell transplantation (HSCT). Objectives: To investigate the clinical response to ruxolitinib in patients with SR-cGVHD after allogeneic HSCT and to evaluate its safety profile during the treatment course. Design, Setting, and Participants: This single-center case series included 41 consecutive patients who were treated with ruxolitinib for SR-cGVHD after allogeneic HSCT between August 2017 and December 2019. Data were collected from each patient's medical record at the First Affiliated Hospital of Zhejiang University School of Medicine. Data analysis was conducted from March to May 2020. Exposure: Ruxolitinib. Main Outcomes and Measures: Treatment responses, factors associated with response, and adverse effects during ruxolitinib administration. Findings: Overall, 41 patients (median [range] age, 31 [17-56] years; 14 [34.1%] women) were treated with ruxolitinib and included in this study. A total of 15 patients (36.6%) had a complete remission, and 14 (34.1%) had a partial remission, with an overall response rate of 70.7% (29 patients; 95% CI, 56.2%-85.3%). Lung involvement (odds ratio, 0.112; 95% CI, 0.020-0.639; P = .01) and matched related donors (odds ratio, 0.149; 95% CI, 0.022-0.981; P = .048) were associated with less favorable treatment response. Major adverse events associated with ruxolitinib were cytopenias and infectious complications. The median (range) follow-up for this cohort was 14.9 (1.4-32.5) months. Prolonged survival was observed in patients with a male donor (P = .006), complete remission before transplantation (P = .02), baseline moderate cGVHD (P = .02), and skin cGVHD (P = .001). Conclusions and Relevance: In this small, single-site case series, ruxolitinib demonstrated a significant response in heavily pretreated patients with SR-cGVHD and a reasonably well-tolerated safety profile. The results add to the body of literature suggesting ruxolitinib as a promising treatment option in SR-cGVHD.


Asunto(s)
Enfermedad Injerto contra Huésped/tratamiento farmacológico , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas , Pirazoles/uso terapéutico , Adolescente , Adulto , Enfermedad Crónica , Femenino , Enfermedad Injerto contra Huésped/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Nitrilos , Pirimidinas , Inducción de Remisión , Esteroides/uso terapéutico
9.
Curr Res Transl Med ; 68(3): 111-118, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32620465

RESUMEN

The pandemic of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is spreading rapidly across the world. Currently, the COVID-19 pandemic is affecting the continuity of essential routine healthcare services and procedures, including chimeric antigen receptor T-cell (CAR-T) therapy, a life-saving option for patients with relapsed/refractory (R/R) hematologic malignancies. Due to the rapid disease progression of hematological malignancies, there is an urgent need to manufacture and utilize CAR T-cells. However, CAR-T treatment has become extraordinarily challenging during this COVID-19 pandemic. Thus, many medical and technical factors must now be taken into consideration before, during, and after CAR-T therapy. The purpose of this review is to provide brief suggestions for rational decision-making strategies in evaluating and selecting CAR T-cell treatment and appropriate CAR T-cell products, and protective strategies for medical staff and patients to prevent infection in the midst of the current COVID-19 pandemic.


Asunto(s)
Infecciones por Coronavirus/prevención & control , Atención a la Salud/organización & administración , Neoplasias Hematológicas/terapia , Inmunoterapia Adoptiva , Control de Infecciones/organización & administración , Pandemias/prevención & control , Neumonía Viral/prevención & control , Receptores de Antígenos de Linfocitos T/inmunología , Betacoronavirus/fisiología , COVID-19 , Infecciones por Coronavirus/epidemiología , Atención a la Salud/métodos , Atención a la Salud/normas , Atención a la Salud/tendencias , Neoplasias Hematológicas/epidemiología , Humanos , Inmunoterapia Adoptiva/métodos , Inmunoterapia Adoptiva/tendencias , Control de Infecciones/métodos , Control de Infecciones/normas , Control de Infecciones/tendencias , Neumonía Viral/epidemiología , Servicios Preventivos de Salud/métodos , Servicios Preventivos de Salud/organización & administración , Servicios Preventivos de Salud/normas , Servicios Preventivos de Salud/tendencias , SARS-CoV-2
10.
Am J Hematol ; 95(9): 1075-1084, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32510625

RESUMEN

About half of patients with severe acute graft vs host disease (aGVHD) show resistance to treatment with first-line steroids. We enrolled 64 patients with grades III-IV SR-aGVHD after allogeneic hematopoietic stem cell transplantation (allo-SCT), to assess the efficacy and safety of the combination therapy of ruxolitinib and etanercept. The overall response rate was 87.5% (95% CI, 79.7%-95.3%) at day 28 of the combination treatment, from which 73.4% reached complete response (CR). A marked reduction ≥75% in daily corticosteroid dosing was documented in 75.4% of patients at day 28. Delayed time from aGVHD to ruxolitinib (OR = 4.88, 95% CI, 0.98-23.56), stages 3-4 liver aGVHD (OR = 8.57, 95% CI, 0.96-46.59) and gut Enterobacteriaceae colonization (OR = 12.39, 95% CI, 1.71-59.77) were related to incomplete response. Grades 3/4 anemia, leukopenia, or thrombocytopenia and CMV-reactivation were found in 29.7%, 26.6%, 39.1%, and 50.0% of patients, respectively. So, 25 (39.1%) experienced complications of severe infection ≥3 grade, in which pulmonary infections were most frequent (15/64, 23.4%). The 2-year overall survival (OS) after the combination therapy was 61.2%. The 2-year incidence of non-relapse mortality and relapse of the underlying malignancy was 26.7% and 15.7%, respectively. Combined treatment with ruxolitinib and etanercept was very effective and relatively safe for severe aGVHD patients, while the various infection complications deserve more attention. This study was registered at the Chinese Clinical Trial Registry (ChiCTR1900024408).


Asunto(s)
Etanercept/administración & dosificación , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Enfermedad Injerto contra Huésped/mortalidad , Trasplante de Células Madre Hematopoyéticas , Pirazoles/administración & dosificación , Enfermedad Aguda , Adolescente , Corticoesteroides/administración & dosificación , Adulto , Aloinjertos , Supervivencia sin Enfermedad , Quimioterapia Combinada , Etanercept/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nitrilos , Estudios Prospectivos , Pirazoles/efectos adversos , Pirimidinas , Tasa de Supervivencia
11.
J Zhejiang Univ Sci B ; 21(1): 29-41, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31898440

RESUMEN

Multiple myeloma (MM), considered an incurable hematological malignancy, is characterized by its clonal evolution of malignant plasma cells. Although the application of autologous stem cell transplantation (ASCT) and the introduction of novel agents such as immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs) have doubled the median overall survival to eight years, relapsed and refractory diseases are still frequent events in the course of MM. To achieve a durable and deep remission, immunotherapy modalities have been developed for relapsed/refractory multiple myeloma (RRMM). Among these approaches, chimeric antigen receptor (CAR) T-cell therapy is the most promising star, based on the results of previous success in B-cell neoplasms. In this immunotherapy, autologous T cells are engineered to express an artificial receptor which targets a tumor-associated antigen and initiates the T-cell killing procedure. Tisagenlecleucel and Axicabtagene, targeting the CD19 antigen, are the two pacesetters of CAR T-cell products. They were approved by the US Food and Drug Administration (FDA) in 2017 for the treatment of acute lymphocytic leukemia (ALL) and diffuse large B-cell lymphoma (DLBCL). Their development enabled unparalleled efficacy in combating hematopoietic neoplasms. In this review article, we summarize six promising candidate antigens in MM that can be targeted by CARs and discuss some noteworthy studies of the safety profile of current CAR T-cell therapy.


Asunto(s)
Inmunoterapia Adoptiva/métodos , Mieloma Múltiple/terapia , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , ADP-Ribosil Ciclasa 1/inmunología , Antígeno de Maduración de Linfocitos B/inmunología , Humanos , Inmunoterapia Adoptiva/efectos adversos , Mieloma Múltiple/inmunología , Receptores Acoplados a Proteínas G/inmunología , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/inmunología , Sindecano-1/inmunología
13.
Am J Physiol Heart Circ Physiol ; 301(5): H2147-53, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21856907

RESUMEN

A chronic increase in the concentration of sodium chloride in the cerebrospinal fluid (CSF) (↑CSF [NaCl]) appears to be critically important for the development of salt-dependent hypertension. In agreement with this concept, increasing CSF [NaCl] chronically by intracerebroventricular (icv) infusion of NaCl-rich artificial CSF (aCSF-HiNaCl) in rats produces hypertension by the same mechanisms (i.e., aldosterone-ouabain pathway in the brain) as that produced by dietary sodium in salt-sensitive strains. We first demonstrate here that icv aCSF-HiNaCl for 10 days also causes hypertension in wild-type (WT) mice. We then used both WT and gene-targeted mice to explore the mechanisms. In WT mice with a ouabain-sensitive Na,K-ATPase α(2)-isoform (α2(S/S)), mean arterial pressure rose by ~25 mmHg within 2 days of starting aCSF-HiNaCl (0.6 nmol Na/min) and remained elevated throughout the study. Ouabain (171 pmol/day icv) increased blood pressure to a similar extent. aCSF-HiNaCl or ouabain given at the same rates subcutaneously instead of intracerebroventricularly had no effect on blood pressure. The pressor response to icv aCSF-HiNaCl was abolished by an anti-ouabain antibody given intracerebroventricularly but not subcutaneously, indicating that it is mediated by an endogenous ouabain-like substance in the brain. We compared the effects of icv aCSF-HiNaCl or icv ouabain on blood pressure in α2(S/S) versus knockout/knockin mice with a ouabain-resistant endogenous α(2)-subunit (α2(R/R)). In α2(R/R), there was no pressor response to icv aCSF-HiNaCl in contrast to WT mice. The α2(R/R) genotype also lacked a pressor response to icv ouabain. These data demonstrate that chronic ↑CSF [NaCl] causes hypertension in mice and that the blood pressure response is mediated by the ouabain-like substance in the brain, specifically by its binding to the α(2)-isoform of the Na,K-ATPase.


Asunto(s)
Presión Sanguínea , Encéfalo/enzimología , Cardenólidos/metabolismo , Hipertensión/enzimología , Saponinas/metabolismo , Cloruro de Sodio/líquido cefalorraquídeo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Sitios de Unión , Monitoreo Ambulatorio de la Presión Arterial , Modelos Animales de Enfermedad , Frecuencia Cardíaca , Hipertensión/líquido cefalorraquídeo , Hipertensión/inducido químicamente , Hipertensión/fisiopatología , Infusiones Intraventriculares , Ratones , Ratones Noqueados , Ratones Transgénicos , Mutación , Ouabaína/administración & dosificación , Cloruro de Sodio/administración & dosificación , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , ATPasa Intercambiadora de Sodio-Potasio/deficiencia , ATPasa Intercambiadora de Sodio-Potasio/genética , Telemetría , Factores de Tiempo
14.
Am J Physiol Regul Integr Comp Physiol ; 296(5): R1427-38, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19244589

RESUMEN

Intracerebroventricular (ICV) infusion of NaCl mimics the effects of a high-salt diet in salt-sensitive hypertension, raising the sodium concentration in the cerebrospinal fluid (CSF [Na]) and subsequently increasing the concentration of an endogenous ouabain-like substance (OLS) in the brain. The OLS, in turn, inhibits the brain Na(+)-K(+)-ATPase, causing increases in the activity of the brain renin-angiotensin system (RAS) and blood pressure. The Na(+)-K(+)-ATPase alpha (catalytic)-isoform(s) that mediates the pressor response to increased CSF [Na] is unknown, but it is likely that one or more isoforms that bind ouabain with high affinity are involved (e.g., the Na(+)-K(+)-ATPase alpha(2)- and/or alpha(3)-subunits). We hypothesize that OLS-induced inhibition of the alpha(2)-subunit mediates this response. Therefore, a chronic reduction in alpha(2) expression via a heterozygous gene knockout (alpha(2) +/-) should enhance the pressor response to increased CSF [Na]. Intracerebroventricular (ICV) infusion of artificial CSF containing 0.225 M NaCl increased mean arterial pressure (MAP) in both wild-type (+/+) and alpha(2) +/- mice, but to a greater extent in alpha(2) +/-. Likewise, the pressor response to ICV ouabain was enhanced in alpha(2) +/- mice, demonstrating enhanced sensitivity to brain Na(+)-K(+)-ATPase inhibition per se. The pressor response to ICV ANG I but not ANG II was also enhanced in alpha(2) +/- vs. alpha(2)+/+ mice, suggesting an enhanced brain RAS activity that may be mediated by increased brain angiotensin converting enzyme (ACE). The latter hypothesis is supported by enhanced ACE ligand binding in the organum vasculosum laminae terminalis. These studies demonstrate that chronic downregulation of Na(+)-K(+)-ATPase alpha(2)-isoform expression by heterozygous knockout increases the pressor response to increased CSF [Na] and activates the brain RAS. Since these changes mimic those produced by the endogenous brain OLS, the brain alpha(2)-isoform may be a target for the brain OLS during increases in CSF [Na], such as in salt-dependent hypertension.


Asunto(s)
Angiotensina I/metabolismo , Presión Sanguínea/fisiología , Encéfalo/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Sodio/líquido cefalorraquídeo , Angiotensina I/administración & dosificación , Angiotensina I/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Hipertensión/metabolismo , Hipertensión/fisiopatología , Hipotálamo/efectos de los fármacos , Hipotálamo/fisiología , Inyecciones Intraventriculares , Masculino , Ratones , Ratones Noqueados , Ouabaína/administración & dosificación , Ouabaína/metabolismo , Ouabaína/farmacología , Sistema Renina-Angiotensina/efectos de los fármacos , Sistema Renina-Angiotensina/fisiología , Sodio/administración & dosificación , Sodio/farmacología , ATPasa Intercambiadora de Sodio-Potasio/genética
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