Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
Bone Marrow Transplant ; 58(8): 849-854, 2023 08.
Article in English | MEDLINE | ID: mdl-37185614

ABSTRACT

Relapse is the most common cause of mortality in acute myeloid leukemia (AML) patients after allogeneic stem cell transplant (SCT). Post-SCT maintenance strategies that prevent relapse are desirable but must be well tolerated and convenient to administer. We hypothesized single agent venetoclax (ven) may be an effective maintenance therapy among high relapse risk patients. Between February 2019 and December 2021, we administered post-SCT ven maintenance to 49 AML patients at high-risk for relapse as a prospectively defined off-label practice at our institution. Ven was planned to be administered until 1-year post-SCT. While temporary interruptions were common (67.3% of all patients), of those with >1 year follow up, 22/25 (88%) completed the full year of planned therapy. Cytopenias (40.8%) and gastrointestinal adverse events (34.7%) were the most common toxicities. At 1-year post-SCT, overall survival (OS) and relapse-free survival (RFS) were 70% and 67% respectively. Our experience demonstrates single agent ven is a safe, tolerable, and feasible maintenance therapy that may improve RFS and OS in high relapse risk post-SCT patients.


Subject(s)
Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute , Humans , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Sulfonamides/therapeutic use , Stem Cell Transplantation , Recurrence , Retrospective Studies
2.
Haematologica ; 108(10): 2616-2625, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37051756

ABSTRACT

Venetoclax+azacitidine is the standard of care for newly-diagnosed patients with acute myeloid leukemia (AML) for whom intensive chemotherapy is inappropriate. Efforts to optimize this regimen are necessary. We designed a clinical trial to investigate two hypotheses: i) higher doses of venetoclax are tolerable and more effective, and ii) azacitidine can be discontinued after deep remissions. Forty-two newly diagnosed AML patients were enrolled in the investigator-initiated High Dose Discontinuation Azacitidine+Venetoclax (HiDDAV) Study (clinicaltrials gov. Identifier: NCT03466294). Patients received one to three "induction" cycles of venetoclax 600 mg daily with azacitidine. Responders received MRD-positive or MRDnegative "maintenance" arms: azacitidine with 400 mg venetoclax or 400 mg venetoclax alone, respectively. The toxicity profile of HiDDAV was similar to 400 mg venetoclax. The overall response rate was 66.7%; the duration of response (DOR), event-free survival (EFS) and overall survival were 12.9, 7.8 and 9.8 months, respectively. The MRD negativity rate was 64.3% by flow cytometry and 25.0% when also measured by droplet digital polymerase chain recation. MRD-negative patients by flow cytometry had improved DOR and EFS; more stringent measures of MRD negativity were not associated with improved OS, DOR or EFS. Using MRD to guide azacitidine discontinuation did not lead to improved DOR, EFS or OS compared to patients who discontinued azacitidine without MRD guidance. Within the context of this study design, venetoclax doses >400 mg with azacitidine were well tolerated but not associated with discernible clinical improvement, and MRD may not assist in recommendations to discontinue azacitidine. Other strategies to optimize, and for some patients, de-intensify, venetoclax+azacitidine regimens are needed.


Subject(s)
Azacitidine , Leukemia, Myeloid, Acute , Humans , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bridged Bicyclo Compounds, Heterocyclic/adverse effects , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/drug therapy , Neoplasm, Residual/drug therapy
3.
Cancer Rep (Hoboken) ; 5(5): e1505, 2022 05.
Article in English | MEDLINE | ID: mdl-34250757

ABSTRACT

BACKGROUND: The time-limited combination of venetoclax and obinutuzumab (VenG) was established by the German CLL Study Group in the CLL14 trial for the upfront management of newly diagnosed chronic lymphocytic leukemia (CLL), showing a superior progression free survival benefit. The incidence of grade 3-4 neutropenia was reported in the range of 52.8%-57.7%. However, patients who develop neutropenia with this combination have yet to be formally characterized in the literature as it has impact on the clinical practice setting. AIM: To determine the incidence of grade 3 and 4 neutropenia and identify risk factors for neutropenia among CLL patients treated with the VenG regimen. METHODS: We conducted a retrospective, single-center study of all adult patients with a diagnosis of CLL treated with VenG at the University of Colorado Hospital. Demographic information, laboratory data, clinical data, and medication prescriptions were collected from the patients' electronic medical record. RESULTS: A total of 14 patients (73%) developed neutropenia during the course of therapy. The mean time to neutropenia from the start of treatment was 42 days (range 1-131). Our cohort harbored more high risk disease features and more comorbidities (CIRS score of 12). Four patients (28.6%) in the neutropenic group developed infectious complications during therapy and 6 (31%) patients were unable to be dose escalated to the final FDA approved dose of 400 mg. CONCLUSION: Our study cohort had higher incidence of grade 3 and 4 neutropenia occurring in 73% of patients. This could be attributed to a higher rate of comorbidities, high risk features, concomitant interacting medications, and prior chemotherapy. Further studies are warranted to determine if growth factor support is efficacious to achieve dose escalation with this therapy.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Neutropenia , Adult , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols , Bridged Bicyclo Compounds, Heterocyclic , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/etiology , Neutropenia/chemically induced , Neutropenia/epidemiology , Retrospective Studies , Risk Factors , Sulfonamides
4.
Risk Anal ; 41(7): 1204-1212, 2021 07.
Article in English | MEDLINE | ID: mdl-33960513

ABSTRACT

This article describes an interdisciplinary community resilience research project and presents a case study that supports bringing researchers together before a disaster to develop plans, procedures, and preapproved Institutional Review Board (IRB) protocols. In addition, this article explains how researchers from various academic institutions and their federal agency partners can effectively collaborate by creating an IRB Authorization Agreement (IAA). Such preparations can support interdisciplinary rapid response disaster fieldwork that is timely, ethically informed, and scientifically rigorous. This fieldwork preplanning process can also advance interdisciplinary team formation and data collection efforts over the long term.


Subject(s)
Disaster Planning/organization & administration , Ethics Committees, Research , Interdisciplinary Research/organization & administration , Research Personnel , Humans , Organizational Case Studies
5.
J Oncol Pharm Pract ; 27(3): 658-672, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33215562

ABSTRACT

OBJECTIVE: Acute myeloid leukemia (AML) is primarily a disease of older adults. These patients may not be candidates for intensive treatment, and there has been an ongoing need for treatment options for this group. We review the use of glasdegib, a hedgehog-pathway inhibitor available for use in combination with low-dose cytarabine (LDAC).Data Sources: PubMed and relevant congress abstracts were searched using the term "glasdegib". In addition, based on our experience with glasdegib, we considered treatment aspects of particular relevance to pharmacists and advanced practitioners.Data Summary: In a randomized phase II study, the combination of glasdegib plus LDAC demonstrated superior overall survival versus LDAC alone (hazard ratio 0.51, 80% confidence interval 0.39-0.67, p = 0.0004). The trial reported adverse events (AEs) of special relevance for older patients, such as hematologic events, gastrointestinal toxicity, and fatigue, as well as AEs associated with Hh-pathway inhibitors (alopecia, muscle spasms, dysgeusia). Educating patients about typical AEs can facilitate adherence as well as early AE identification and proactive management. For LDAC, which is a long-established therapy in AML, various stages of delivery need consideration, with attention to individual circumstances. Practical measures such as dispensing a longer supply can reduce the number of return clinic visits, providing a meaningful difference for many patients. CONCLUSIONS: Pharmacists and advanced practitioners play important roles in treatment with glasdegib plus LDAC. Ultimately, framing plans for treatment delivery within the individual circumstances of each patient may enable them to stay on therapy longer, giving them the greatest potential to achieve benefit.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Benzimidazoles/administration & dosage , Cytarabine/administration & dosage , Leukemia, Myeloid, Acute/drug therapy , Pharmacists/standards , Phenylurea Compounds/administration & dosage , Physicians/standards , Aged , Aged, 80 and over , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Benzimidazoles/adverse effects , Cytarabine/adverse effects , Drug Interactions/physiology , Female , Gastrointestinal Diseases/chemically induced , Hematologic Diseases/chemically induced , Humans , Leukemia, Myeloid, Acute/diagnosis , Male , Phenylurea Compounds/adverse effects
6.
Bone Marrow Transplant ; 55(4): 780-786, 2020 04.
Article in English | MEDLINE | ID: mdl-31664185

ABSTRACT

We compared CMV outcomes of three prophylactic approaches used for CBT and haploidentical cord transplants from December 2009 through 2018: letermovir (n = 32) through day 100 post transplant, "valacyclovir day 100" (valacyclovir 2 g orally three times daily through day 100) (n = 60), and "valacyclovir hospital discharge" (valacyclovir 2 g orally three times daily through hospital discharge then acyclovir 800 mg twice daily) (n = 41). Through day 100, none in the letermovir group, six (10%) in the "valacyclovir day 100," and nine (22%) in the "valacyclovir hospital discharge" group required CMV directed treatment (p = 0.005 and 0.06 comparing letermovir to "valacyclovir hospital discharge" and "valacyclovir day 100"). Fewer patients in the letermovir group (n = 7, 22%) had any CMV reactivation versus the "valacyclovir day 100" group (n = 20, 33%) versus the "valacyclovir hospital discharge" group (n = 23, 57%) (p = 0.003 and 0.21 comparing letermovir to "valacyclovir hospital discharge" and "valacyclovir day 100"). Among patients not reactivating CMV before 100 days, reactivation rates between day 100 and 180 were higher in the letermovir and "valacyclovir day 100" groups than the "valacyclovir hospital discharge" group. Letermovir is safe and effective compared with alternative prophylaxis approaches following CBT through day 100. Reactivation and monitoring after day 100 remain potential concerns.


Subject(s)
Cord Blood Stem Cell Transplantation , Cytomegalovirus Infections , Acetates , Adult , Antiviral Agents/therapeutic use , Cytomegalovirus Infections/drug therapy , Cytomegalovirus Infections/prevention & control , Fetal Blood , Humans , Quinazolines
7.
Blood Adv ; 3(20): 2911-2919, 2019 10 22.
Article in English | MEDLINE | ID: mdl-31648312

ABSTRACT

Venetoclax is approved for older untreated acute myeloid leukemia (AML) patients. Venetoclax was available prior to approval off-label. We assessed our single-institution off-label experience with venetoclax/azacitidine, comparing outcomes with a clinical trial cohort that administered this regimen at the same institution. Thirty-three untreated AML patients unfit or unwilling to receive induction chemotherapy and prescribed venetoclax/azacitidine off-trial were retrospectively analyzed and compared with 33 patients who received the same therapy on trial. Outcomes were compared, and comparisons were made to a theoretical scenario in which off-trial patients received induction. Digital droplet polymerase chain reaction evaluated measurable residual disease (MRD). Off-trial venetoclax was attainable in nearly all patients for whom this was desired. The complete remission (CR)/CR with incomplete blood count recovery rate was 63.3% for off-trial patients who received treatment and 84.9% for trial patients (P = .081). The median overall survival for off-trial patients who received treatment was 381 days (95% confidence interval [CI], 174, not reached) vs 880 days (95% CI, 384, not reached) for trial patients (P = .041). Prior exposure to hypomethylating agents was associated with worse outcomes. Response rates with venetoclax/azacitidine were not inferior to a theoretical scenario in which patients received induction, and early death rates were less than expected with induction. MRD negativity was achievable. Newly diagnosed AML patients treated in a "real-world" scenario with off-trial venetoclax/azacitidine had inferior outcomes compared with patients treated in the setting of a clinical trial. Additionally, this therapy may be as effective, and less toxic, when compared with induction chemotherapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Azacitidine/administration & dosage , Bridged Bicyclo Compounds, Heterocyclic/administration & dosage , Female , Follow-Up Studies , Genetic Testing , Humans , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/etiology , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Neoplasm, Residual/diagnosis , Prognosis , Remission Induction , Sulfonamides/administration & dosage , Treatment Outcome
8.
Biol Blood Marrow Transplant ; 25(10): 2091-2097, 2019 10.
Article in English | MEDLINE | ID: mdl-31255741

ABSTRACT

Clostridioides difficile infection (CDI) is a common complication in the hematopoietic stem cell transplantation (HSCT) and hematologic malignancy (HM) population. CDI is associated with increased hospital length of stay, health care and societal costs, morbidity, and mortality. Identifying strategies for secondary prevention of CDI is of extreme importance in the HSCT/HM population. In this study, our primary objective was to evaluate the effectiveness and safety of an oral vancomycin prophylaxis (OVP) protocol for secondary prevention of CDI in a retrospective cohort of adult autologous/allogeneic HSCT recipients and patients with HM who did not undergo HSCT with a first CDI episode treated with concomitant broad-spectrum antibiotics (BSA). Patients were diagnosed and treated for CDI as inpatients and/or outpatients and were divided into 2 groups based on a preprotocol versus postprotocol analysis: the OVP group, comprising patients who received planned monotherapy with oral vancomycin 125 mg every 6 hours for 14 days for a first episode of CDI and subsequently received OVP posttreatment and a no OVP (NOVP) group, comprising patients who received planned monotherapy with oral vancomycin 125 mg every 6 hours for 14 days for a first episode of CDI and subsequently did not receive OVP posttreatment. OVP was defined as vancomycin 125 mg every 12 hours for up to 7 days after BSA discontinuation. The primary endpoint was recurrent CDI (rCDI), defined as symptoms of loose stools/diarrhea with high clinical suspicion for CDI prompting empiric therapy within 60 days of completion of treatment/prophylaxis for the first CDI episode. The incidence of vancomycin-resistant enterococcal (VRE) infection and 60-day mortality were also compared between the 2 groups. Multivariate logistic regression was created from associated variables to identify independent associations with rCDI. A total of 50 patients were included, 21 in the OVP group (42%) and 29 in the NOVP group (58%). The mean patient age was 58 years, and the cohort was 60% male and 86% Caucasian. HSCT was performed in 60% of the patients, and 76% of CDI cases were diagnosed during hospitalization. The rate of rCDI was significantly lower in the OVP group compared with the NOVP group (5% [1 of 21] versus 35% [10 of 29]; P= .016), with no subsequent increase in VRE infection rate (14% [3 of 21] versus 10% [3 of 29]; P = .686). By multivariable logistic regression, rCDI was inversely associated with OVP (odds ratio [OR], .14; 95% confidence interval [CI], .007 to .994; P = .049) and directly associated with outpatient CDI diagnosis (OR, 8.72; 95% CI, 1.816 to 49.158; P = .007). No between-group differences were found in 60-day mortality (10% [2 of 21] for OVP versus 7% [2 of 29] for NOVP; P > 0.999). OVP appears to be safe and effective for secondary prevention of CDI in the HSCT/HM population. Prospective trials are needed to validate the effectiveness of OVP in this vulnerable population to prevent rCDI.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Clostridioides difficile/pathogenicity , Clostridium Infections/drug therapy , Hematologic Neoplasms/complications , Hematopoietic Stem Cell Transplantation/adverse effects , Transplantation Conditioning/adverse effects , Vancomycin/pharmacology , Vancomycin/therapeutic use , Administration, Oral , Adult , Aged , Anti-Bacterial Agents/pharmacology , Female , Humans , Male , Middle Aged , Retrospective Studies
10.
Mol Pharmacol ; 92(6): 694-706, 2017 12.
Article in English | MEDLINE | ID: mdl-28974538

ABSTRACT

Bromodomain (BD) and extra-terminal domain containing proteins (BET) are chromatin adapters that bind acetylated histone marks via two tandem BDs, BD1 and BD2, to regulate gene transcription. BET proteins are involved in transcriptional reprogramming in response to inflammatory stimuli. BET BD inhibitors (BETis) that are nonselective for BD1 or BD2 have recognized anti-inflammatory properties in vitro and counter pathology in models of inflammation or autoimmune disease. Although both BD1 and BD2 bind acetylated histone residues, they may independently regulate the expression of BET-sensitive genes. Here we characterized the ability of RVX-297, a novel orally active BETi with selectivity for BD2, to modulate inflammatory processes in vitro, in vivo, and ex vivo. RVX-297 suppressed inflammatory gene expression in multiple immune cell types in culture. Mechanistically, RVX-297 displaced BET proteins from the promoters of sensitive genes and disrupted recruitment of active RNA polymerase II, a property shared with pan-BETis that nonselectively bind BET BDs. In the lipopolysaccharide model of inflammation, RVX-297 reduced proinflammatory mediators assessed in splenic gene expression and serum proteins. RVX-297 also countered pathology in three rodent models of polyarthritis: rat and mouse collagen-induced arthritis, and mouse collagen antibody-induced arthritis. Further, RVX-297 prevented murine experimental autoimmune encephalomyelitis (a model of human multiple sclerosis) disease development when administered prophylactically and reduced hallmarks of pathology when administered therapeutically. We show for the first time that a BD2-selective BETi maintains anti-inflammatory properties and is effective in preclinical models of acute inflammation and autoimmunity.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Arthritis/drug therapy , Autoimmune Diseases/drug therapy , Proteins/antagonists & inhibitors , Quinazolinones/therapeutic use , Acute Disease , Animals , Anti-Inflammatory Agents/therapeutic use , Antibodies/immunology , Arthritis/chemically induced , Arthritis/immunology , Arthritis/pathology , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/pathology , Autoimmune Diseases/immunology , Autoimmune Diseases/pathology , B-Lymphocytes/drug effects , B-Lymphocytes/metabolism , Cells, Cultured , Collagen/immunology , Cytokines/biosynthesis , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/immunology , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , Humans , Inflammation/drug therapy , Inflammation/metabolism , Lipopolysaccharides/pharmacology , Male , Mice, Inbred C57BL , Rats, Inbred Lew , Spleen/drug effects , Spleen/metabolism , Spleen/pathology , U937 Cells
12.
Leuk Lymphoma ; 57(4): 927-34, 2016.
Article in English | MEDLINE | ID: mdl-26389776

ABSTRACT

A rare but well-known association between plasma cell neoplasms and neutrophilia is known to exist. Whether the neutrophilia is secondary to the plasma cell neoplasm or this convergence represents two independent clonal disorders is unclear. We reviewed five consecutive cases from a single institution over a 3-year period, applying molecular, cytogenetic and cytokine-profiling approaches to determine whether neutrophilia associated with plasma cell neoplasms represents a reactive or clonal process. We report, for the first time, the occurrence of a SETBP1 mutation in two cases, as well as changes in G-CSF and IL-6 in SETBP1 wild type vs. mutated patients that are supportive of a hypothesis that neutrophilia associated with plasma cell neoplasms may sometimes be reactive and may sometimes represent a second clonal entity. Finally, using an ex vivo drug screening platform we report the potential efficacy of the multi-kinase inhibitor dasatinib in select patients.


Subject(s)
Carrier Proteins/genetics , Clonal Evolution , Leukocytosis/pathology , Mutation , Neoplasms, Plasma Cell/genetics , Neoplasms, Plasma Cell/pathology , Neutrophils/pathology , Nuclear Proteins/genetics , Aged , Biopsy , Bone Marrow/pathology , Chromosome Aberrations , Cytokines/metabolism , DNA Mutational Analysis , Female , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Neoplasms, Plasma Cell/metabolism , Retrospective Studies
13.
Atherosclerosis ; 236(1): 91-100, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25016363

ABSTRACT

Despite the benefit of statins in reducing cardiovascular risk, a sizable proportion of patients still remain at risk. Since HDL reduces CVD risk through a process that involves formation of pre-beta particles that facilitates the removal of cholesterol from the lipid-laden macrophages in the arteries, inducing pre-beta particles, may reduce the risk of CVD. A novel BET bromodomain antagonist, RVX-208, was reported to raise apoA-I and increase preß-HDL particles in non-human primates and humans. In the present study, we investigated the effect of RVX-208 on aortic lesion formation in hyperlipidemic apoE(-/-) mice. Oral treatments of apoE(-/-) mice with 150 mg/kg b.i.d RVX-208 for 12 weeks significantly reduced aortic lesion formation, accompanied by 2-fold increases in the levels of circulating HDL-C, and ∼50% decreases in LDL-C, although no significant changes in plasma apoA-I were observed. Circulating adhesion molecules as well as cytokines also showed significant reduction. Haptoglobin, a proinflammatory protein, known to bind with HDL/apoA-I, decreased >2.5-fold in the RVX-208 treated group. With a therapeutic dosing regimen in which mice were fed Western diet for 10 weeks to develop lesions followed by switching to a low fat diet and concurrent treatment with RVX-208 for 14 weeks, RVX-208 similarly reduced lesion formation by 39% in the whole aorta without significant changes in the plasma lipid parameters. RVX-208 significantly reduced the proinflammatory cytokines IP-10, MIP1(®) and MDC. These results show that the antiatherogenic activity of BET inhibitor, RVX-208, occurs via a combination of lipid changes and anti-inflammatory activities.


Subject(s)
Aortic Diseases/prevention & control , Atherosclerosis/prevention & control , Betaine-Homocysteine S-Methyltransferase/antagonists & inhibitors , Hyperlipidemias/drug therapy , Quinazolines/therapeutic use , Animals , Aorta/drug effects , Aorta/metabolism , Aorta/pathology , Aortic Diseases/blood , Aortic Diseases/etiology , Aortic Diseases/pathology , Apolipoprotein A-I/blood , Apolipoproteins E/deficiency , Atherosclerosis/blood , Atherosclerosis/etiology , Atherosclerosis/pathology , Cell Line , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cytokines/blood , Diet, Fat-Restricted , Diet, Western/adverse effects , Drug Evaluation, Preclinical , Endothelial Cells , Gene Expression Profiling , Humans , Hyperlipidemias/blood , Hyperlipidemias/complications , Hyperlipidemias/diet therapy , Hyperlipidemias/genetics , Inflammation/blood , Inflammation/prevention & control , Liver/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Quinazolines/pharmacology , Quinazolinones , RNA, Messenger/analysis , U937 Cells
14.
Glia ; 60(9): 1378-90, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22615173

ABSTRACT

Leukemia/lymphoma-related factor (LRF) is a zinc-finger transcription factor that regulates differentiation and oncogenesis in multiple tissues and cell lineages. The potential role for LRF in cells of the CNS has not been examined to date. This study shows prominent nuclear expression of LRF in diverse neuronal populations and in oligodendrocytes. We focused on examining the function of LRF during the transition from oligodendrocyte progenitor (OP) to mature oligodendrocyte that is associated with myelination in the postnatal spinal cord. During spinal cord myelination, LRF is expressed in only a minority of OP cells whereas most mature oligodendrocytes exhibited nuclear LRF immunoreactivity. Mice with floxed alleles of the Zbtb7a gene, which encodes for LRF protein, were used for in vivo analysis of LRF function. Lentiviral driven Cre recombinase inactivation of LRF at postnatal day 7 reduced the proportion of OP cells that differentiated into mature oligodendrocytes by postnatal day 28. Astrocyte populations were not altered by LRF deletion in the same tissues. These results indicate that LRF deletion reduces differentiation within the oligodendrocyte lineage and does not alter OP lineage choice. In vitro analysis confirmed a specific effect of LRF on OP differentiation. In neonatal OP cultures, RNA interference targeting LRF inhibited OP differentiation while LRF transduction was sufficient to induce differentiation into oligodendrocytes. These results support a critical role for LRF in transcriptional control of differentiation in oligodendrocyte lineage cells during developmental myelination in the CNS.


Subject(s)
Cell Differentiation/physiology , Cell Lineage/physiology , DNA-Binding Proteins/metabolism , Myelin Sheath/metabolism , Nerve Fibers, Myelinated/metabolism , Oligodendroglia/metabolism , Transcription Factors/metabolism , Alleles , Animals , Axons/metabolism , DNA-Binding Proteins/genetics , Mice , Mice, Transgenic , Oligodendroglia/cytology , Spinal Cord/growth & development , Spinal Cord/metabolism , Stem Cells/cytology , Stem Cells/metabolism , Transcription Factors/genetics
15.
J Neuropathol Exp Neurol ; 70(2): 157-65, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21343885

ABSTRACT

Chronic central nervous system demyelinating diseases result in long-term disability because of limited remyelination capacity and cumulative damage to axons. Corpus callosum demyelination in mice fed cuprizone provides a reproducible model of chronic demyelination in which the demyelinating agent can be removed to test modifications that promote recovery and to develop noninvasive neuroimaging techniques for monitoring changes in myelin and axons. We used the cuprizone model in mice with genetic deletion of fibroblast growth factor 2 (Fgf2) to determine the impact of FGF2 on axon pathology and remyelination after chronic demyelination. We also evaluated the ability of quantitative magnetic resonance diffusion tensor imaging (DTI) to distinguish the corresponding pathological changes in axons and myelin during the progression of demyelination and remyelination. During the recovery period after chronic demyelination, Fgf2-null mice exhibited enhanced remyelination that was detected using DTI measures of radial diffusivity and confirmed by electron microscopic analysis of the proportion of remyelinated axons. Ultrastructural analysis also demonstrated reduced axonal atrophy in chronically demyelinated Fgf2-null versus wild-type mice. This difference in axon atrophy was further demonstrated as reduced immunohistochemical detection of neurofilament dephosphorylation in Fgf2-null mice. Diffusion tensor imaging axial and radial diffusivity measures did not differentiate Fgf2-null mice from wild-type mice to correlate with changes in axonal atrophy during chronic demyelination. Overall, these findings demonstrate that attenuation of FGF2 signaling promotes neuroprotection of axons and remyelination, suggesting that FGF2 is an important negative regulator of recovery after chronic demyelination.


Subject(s)
Axons/pathology , Demyelinating Diseases/pathology , Fibroblast Growth Factor 2/genetics , Myelin Sheath/pathology , Animals , Axons/ultrastructure , Chelating Agents/toxicity , Chronic Disease , Cuprizone/toxicity , Diet , Diffusion Tensor Imaging , Mice , Mice, Inbred C57BL , Mice, Knockout , Myelin Sheath/ultrastructure , Regeneration
16.
J Neuropathol Exp Neurol ; 69(7): 704-16, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20535036

ABSTRACT

Noninvasive assessment of the progression of axon damage is important for evaluating disease progression and developing neuroprotective interventions in multiple sclerosis patients. We examined the cellular responses correlated with diffusion tensor imaging-derived axial (lambda(parallel)) and radial (lambda(perpendicular)) diffusivity values throughout acute (4 weeks) and chronic (12 weeks) stages of demyelination and after 6 weeks of recovery using the cuprizone demyelination of the corpus callosum model in C57BL/6 and Thy1-YFP-16 mice. The rostrocaudal progression of pathological alterations in the corpus callosum enabled spatially and temporally defined correlations of pathological features with diffusion tensor imaging measurements. During acute demyelination, microglial/macrophage activation was most extensive and axons exhibited swellings, neurofilament dephosphorylation, and reduced diameters. Axial diffusivity values decreased in the acute phase but did not correlate with axonal atrophy during chronic demyelination. In contrast, radial diffusivity increased with the progression of demyelination but did not correlate with myelin loss or astrogliosis. Unlike other animal models with progressive neurodegeneration and axon loss, the acute axon damage did not progress to discontinuity or loss of axons even after a period of chronic demyelination. Correlations of reversible axon pathology, demyelination, microglia/macrophage activation, and astrogliosis with regional axial and radial diffusivity measurements will facilitate the clinical application of diffusion tensor imaging in multiple sclerosis patients.


Subject(s)
Corpus Callosum/pathology , Demyelinating Diseases/chemically induced , Demyelinating Diseases/pathology , Diffuse Axonal Injury/etiology , Animals , CD11b Antigen/metabolism , Corpus Callosum/ultrastructure , Cuprizone , Demyelinating Diseases/complications , Diffuse Axonal Injury/pathology , Diffusion Magnetic Resonance Imaging/methods , Disease Models, Animal , Disease Progression , Glial Fibrillary Acidic Protein/metabolism , Indoles , Luminescent Proteins/genetics , Macrophages/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Microglia/pathology , Microscopy, Electron, Transmission , Myelin Proteins , Myelin-Associated Glycoprotein/metabolism , Myelin-Oligodendrocyte Glycoprotein , Neurofilament Proteins/metabolism , Statistics as Topic , Time Factors
17.
Proc Natl Acad Sci U S A ; 106(36): 15418-23, 2009 Sep 08.
Article in English | MEDLINE | ID: mdl-19706393

ABSTRACT

The cardiovascular complications of obesity have prompted interest in dietary interventions to reduce weight, including low-carbohydrate diets that are generally high in protein and fat. However, little is known about the long-term effects of these diets on vascular health. We examined the cardiovascular effects of a low-carbohydrate, high-protein diet (LCHP) in the ApoE(-/-) mouse model of atherosclerosis and in a model of ischemia-induced neovascularization. Mice on a LCHP were compared with mice maintained on either the standard chow diet (SC) or the Western diet (WD) which contains comparable fat and cholesterol to the LCHP. LCHP-fed mice developed more aortic atherosclerosis and had an impaired ability to generate new vessels in response to tissue ischemia. These changes were not explained by alterations in serum cholesterol, inflammatory mediators or infiltrates, or oxidative stress. The LCHP diet substantially reduced the number of bone marrow and peripheral blood endothelial progenitor cells (EPCs), a marker of vascular regenerative capacity. EPCs from mice on a LCHP diet also manifest lower levels of activated (phosphorylated) Akt, a serine-threonine kinase important in EPC mobilization, proliferation, and survival. Taken together, these data demonstrate that in animal models LCHP diets have adverse vascular effects not reflected in serum markers and that nonlipid macronutrients can modulate vascular progenitor cells and pathophysiology.


Subject(s)
Atherosclerosis/etiology , Diet, Carbohydrate-Restricted/adverse effects , Dietary Proteins/adverse effects , Neovascularization, Physiologic/drug effects , Analysis of Variance , Animals , Apolipoproteins E/genetics , Cholesterol/blood , Chromatography, Liquid , Dietary Proteins/administration & dosage , Flow Cytometry , Mice , Mice, Knockout , Proto-Oncogene Proteins c-akt/metabolism , Stem Cells/cytology , Stem Cells/drug effects
18.
Obesity (Silver Spring) ; 17(12): 2182-9, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19461589

ABSTRACT

The National Heart, Lung, and Blood Institute Family Heart Study (FHS) genome-wide linkage scan identified a region of chromosome 7q31-34 with a lod score of 4.9 for BMI at D7S1804 (131.9 Mb). We report the results of linkage and association to BMI in this region for two independent FHS samples. The first sample includes 225 FHS pedigrees with evidence of linkage to 7q31-34, using 1,132 single-nucleotide polymorphisms (SNPs) and 7 microsatellites. The second represents a case-control sample (318 cases; BMI >25 and 325 controls; BMI <25) derived from unrelated FHS participants who were not part of the genome scan. The latter set was genotyped for 606 SNPs, including 37 SNPs with prior evidence for association in the linked families. Although variance components linkage analysis using only SNPs generated a peak lod score that coincided with the original linkage scan at 131.9 Mb, a conditional linkage analysis showed evidence of a second quantitative trait locus (QTL) near 143 cM influencing BMI. Three SNPs (rs161339, rs12673281, and rs1993068) located near the three genes pleiotrophin (PTN), diacylglycerol (DAG) kinase iota (DGK iota), and cholinergic receptor, muscarinic 2 (CHRM2) demonstrated significant association in both linked families (P = 0.0005, 0.002, and 0.03, respectively) and the case-control sample (P = 0.01, 0.0003, and 0.03, respectively), regardless of the genetic model tested. These findings suggest that several genes may be associated with BMI in the 7q31-34 region.


Subject(s)
Body Mass Index , Body Weight/genetics , Chromosomes, Human, Pair 7 , Genetic Linkage , Obesity, Abdominal/genetics , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Adult , Aged , Carrier Proteins/genetics , Case-Control Studies , Chromosome Mapping , Cytokines/genetics , Diacylglycerol Kinase/genetics , Female , Genome-Wide Association Study , Genotype , Humans , Lod Score , Male , Microsatellite Repeats , Middle Aged , National Heart, Lung, and Blood Institute (U.S.) , Pedigree , Receptor, Muscarinic M2/genetics , Receptors, Cholinergic/genetics , United States
19.
Arterioscler Thromb Vasc Biol ; 29(1): 19-26, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18948635

ABSTRACT

OBJECTIVE: The scavenger receptors SR-A and CD36 have been implicated in macrophage foam cell formation during atherogenesis and in the regulation of inflammatory signaling pathways, including those leading to lesional macrophage apoptosis and plaque necrosis. To test the impact of deleting these receptors, we generated Apoe(-/-) mice lacking both SR-A and CD36 and fed them a Western diet for 12 weeks. METHODS AND RESULTS: We analyzed atheroma in mice, assessing lesion size, foam cell formation, inflammatory gene expression, apoptosis, and necrotic core formation. Aortic root atherosclerosis in Apoe(-/-)Cd36(-/-)Msr1(-/-) mice, as assessed by morphometry, electron microscopy, and immunohistochemistry, showed no decrease in lesion area or in vivo foam cell formation when compared to Apoe(-/-) mice. However, Apoe(-/-)Cd36(-/-)Msr1(-/-) lesions showed reduced expression of inflammatory genes and morphological analysis revealed a approximately 30% decrease in macrophage apoptosis and a striking approximately 50% decrease in plaque necrosis in aortic root lesions of these mice. CONCLUSIONS: Although targeted deletion of SR-A and CD36 does not abrogate macrophage foam cell formation or substantially reduce atherosclerotic lesion area in Apoe(-/-) mice, loss of these pathways does reduce progression to more advanced necrotic lesions. These data suggest that targeted inhibition of these pathways in vivo may reduce lesional inflammation and promote plaque stability.


Subject(s)
Atherosclerosis/pathology , CD36 Antigens/deficiency , Foam Cells/pathology , Hyperlipidemias/physiopathology , Scavenger Receptors, Class A/deficiency , Animals , Aorta/pathology , Apolipoproteins E/deficiency , Atherosclerosis/genetics , Disease Models, Animal , Female , Gene Expression Profiling , Gene Expression Regulation , Hyperlipidemias/genetics , Inflammation/genetics , Inflammation/physiopathology , Mice , Mice, Knockout , RNA/genetics , RNA/isolation & purification
20.
Drug Metabol Drug Interact ; 24(2-4): 153-82, 2009.
Article in English | MEDLINE | ID: mdl-20408498

ABSTRACT

AIM: To evaluate the drug interactions between valproic acid (VPA) and carbapenem antibiotics. METHODS: The effects of concurrent use of VPA and carbapenem antibiotics were evaluated in a retrospective observational study of hospitalized adults. Patients receiving both VPA and a carbapenem with at least two plasma VPA concentrations serially measured prior to, during, and/or after this combined treatment were included. RESULTS: Six critically ill VPA-treated patients were identified who concurrently received meropenem (n=4), imipenem (n=1), or ertapenem (n=1). As compared with values obtained while not receiving treatment with the carbapenem, mean plasma VPA trough concentrations decreased by 58% (from 51.7 [95% confidence interval {CI} 28.0-75.4] to 21.8 [95% CI 11.1-32.5] mg/L; p = 0.025). Estimated mean VPA clearance increased by 191% (from 0.0158 [95% CI 0.0041-0.0275] to 0.0302 [95% CI 0.0169-0.0591] L/h/kg; p = 0.007). All VPA concentrations measured during concurrent VPA-carbapenem treatment were below the lower boundary of the usual therapeutic range. Five patients (83%) experienced generalized seizures during concurrent VPA-carbapenem treatment, including two with no prior history of seizures or epilepsy. CONCLUSIONS: All recipients showed evidence of a complex pharmacokinetic and pharmacodynamic drug interaction between VPA and a carbapenem. Concurrent use of these medications should be avoided.


Subject(s)
Anticonvulsants/blood , Antimanic Agents/blood , Carbapenems/pharmacology , Valproic Acid/blood , Adult , Aged , Anticonvulsants/adverse effects , Antimanic Agents/adverse effects , Carbapenems/adverse effects , Drug Interactions , Female , Humans , Male , Middle Aged , Recurrence , Retrospective Studies , Seizures/chemically induced , Valproic Acid/adverse effects
SELECTION OF CITATIONS
SEARCH DETAIL