Inducible knockdown of pregnancy-associated plasma protein-A gene expression in adult female mice extends life span.
ABSTRACT: Pregnancy-associated plasma protein-A (PAPP-A) knockout (KO) mice, generated through homologous recombination in embryonic stem cells, have a significantly increased lifespan compared to wild-type littermates. However, it is unknown whether this longevity advantage would pertain to PAPP-A gene deletion in adult animals. In the present study, we used tamoxifen (Tam)-inducible Cre recombinase-mediated excision of the floxed PAPP-A (fPAPP-A) gene in mice at 5 months of age. fPAPP-A mice, which were either positive (pos) or negative (neg) for Tam-Cre, received Tam treatment with quarterly boosters. Only female mice could be used with this experimental design. fPAPP-A/neg and fPAPP-A/pos mice had similar weights at the start of the experiment and showed equivalent weight gain. We found that fPAPP-A/pos mice had a significant extension of life span (P = 0.005). The median life span was increased by 21% for fPAPP-A/pos compared to fPAPP-A/neg mice. Analysis of mortality in life span quartiles indicated that the proportion of deaths of fPAPP-A/pos mice were lower than fPAPP-A/neg mice at young adult ages (P = 0.002 for 601-800 days) and higher than fPAPP-A/neg mice at older ages (P = 0.004 for >1000 days). Thus, survival curves and age-specific mortality indicate that female mice with knockdown of PAPP-A gene expression as adults have an extended healthy life span.
Project description:Mutations in desmosome proteins cause arrhythmogenic cardiomyopathy (AC), a disease characterized by excess myocardial fibroadipocytes. Cellular origin(s) of fibroadipocytes in AC is unknown.To identify the cellular origin of adipocytes in AC.Human and mouse cardiac cells were depleted from myocytes and flow sorted to isolate cells expressing platelet-derived growth factor receptor-? and exclude those expressing other lineage and fibroblast markers (CD32, CD11B, CD45, Lys76, Ly(-6c) and Ly(6c), thymocyte differentiation antigen 1, and discoidin domain receptor 2). The PDGFRA(pos):Lin(neg):THY1(neg):DDR2(neg) cells were bipotential as the majority expressed collagen 1 ?-1, a fibroblast marker, and a subset CCAAT/enhancer-binding protein ?, a major adipogenic transcription factor, and therefore, they were referred to as fibroadipocyte progenitors (FAPs). FAPs expressed desmosome proteins, including desmoplakin, predominantly in the adipogenic but not fibrogenic subsets. Conditional heterozygous deletion of Dsp in mice using Pdgfra-Cre deleter led to increased fibroadipogenesis in the heart and mild cardiac dysfunction. Genetic fate mapping tagged 41.4±4.1% of the cardiac adipocytes in the Pdgfra-Cre:Eyfp:Dsp(W/F) mice, indicating an origin from FAPs. FAPs isolated from the Pdgfra-Cre:Eyfp:Dsp(W/F) mouse hearts showed enhanced differentiation to adipocytes. Mechanistically, deletion of Dsp was associated with suppressed canonical Wnt signaling and enhanced adipogenesis. In contrast, activation of the canonical Wnt signaling rescued adipogenesis in a dose-dependent manner.A subset of cardiac FAPs, identified by the PDGFRA(pos):Lin(neg):THY1(neg):DDR2(neg) signature, expresses desmosome proteins and differentiates to adipocytes in AC through a Wnt-dependent mechanism. The findings expand the cellular spectrum of AC, commonly recognized as a disease of cardiac myocytes, to include nonmyocyte cells in the heart.
Project description:Pain is a frequent symptom in aquaporin-4-immunoglobulin-G-positive neuromyelitis optica spectrum disorders (AQP4-IgG-pos. NMOSD). Data on pain in myelin-oligodendrocyte-glycoprotein-immunoglobulin-G autoimmunity with a clinical NMOSD phenotype (MOG-IgG-pos. NMOSD) are scarce.The objective of this paper is to investigate pain in MOG-IgG-pos. NMOSD, AQP4-IgG-pos. NMOSD and NMOSD without AQP4/MOG-IgG detection (AQP4/MOG-IgG-neg. NMOSD).Forty-nine MOG-IgG-pos. (n?=?14), AQP4-IgG-pos. (n?=?29) and AQP4/MOG-IgG-neg. (n?=?6) NMOSD patients were included in this cross-sectional baseline analysis from an ongoing observational study. We identified spinal cord lesions on magnetic resonance imaging, assessed pain by the painDETECT and McGill Pain questionnaires, quality of life by Short Form Health Survey, and depression by Beck Depression Inventory.Twelve MOG-IgG-pos. NMOSD patients (86%), 24 AQP4-IgG-pos. NMOSD patients (83%), and all AQP4/MOG-IgG-neg. NMOSD patients (100%) suffered from pain. MOG-IgG-pos. NMOSD patients had mostly neuropathic pain and headache; AQP4-IgG-pos. and AQP4/MOG-IgG-neg. NMOSD patients had mostly neuropathic pain. A history of myelitis was less frequent in MOG-IgG-pos. NMOSD than in AQP4-IgG-pos. NMOSD patients. Pain influenced quality of life in all patients. Thirty-six percent of patients with pain received pain medication; none of them were free of pain.Pain is a frequent symptom of patients with MOG-IgG-pos. NMOSD and is as important as in AQP4-IgG-pos. and AQP4/MOG-IgG-neg. NMOSD. Despite its impact on quality of life, pain is insufficiently alleviated by medication.
Project description:T-cell recognition of tumor antigens presented on tumor-infiltrating macrophages (TAMs) induces a tumoricidal M1-like phenotype. Resultant indirect immune responses could eliminate not only antigen secreting (Ag(POS)), but also antigen negative (Ag(NEG)) tumor cells via bystander killing. Such broad-spectrum response could eliminate antigenically heterogeneous tumors. Using an in vivo model of CD4(+) T-cell mediated immunity against MHC II negative myeloma cells, bystander killing of Ag(NEG) cells was ineffective due to strict spatial constraints of Th1-induced TAM cytotoxicity.
Project description:The pregnancy-associated plasma protein-A knockout (PAPP-A KO) mouse is a model of reduced local insulin-like growth factor (IGF)-I activity with normal circulating IGF-I levels. In this study, PAPP-A KO mice had significantly increased mean (27%), median (27%), and maximum (35%) life span compared with wild-type (WT) littermates. End-of-life pathology indicated that the incidence of neoplastic disease was not significantly different in the two groups of mice; however, it occurred in older aged PAPP-A KO compared with WT mice. Furthermore, PAPP-A KO mice were less likely to show degenerative changes of age. Scheduled pathologies at 78, 104, and 130 weeks of age indicated that WT mice, in general, had more degenerative changes and tumors earlier than PAPP-A KO mice. This was particularly true for abnormalities in heart, testes, brain, kidney, spleen, and thymus. In summary, the major contributors to the extended life span of PAPP-A KO mice are delayed occurrence of fatal neoplasias and decreased incidence of age-related degenerative changes.
Project description:HIV-infected (HIV-pos) male children/youth showed lower bone mineral density at sexual maturity than HIV-uninfected (HIV-neg) females. It is not known whether complications of HIV disease, including abnormal body fat distribution, contribute to lower bone accrual in male HIV-pos adolescents.In a cross-sectional study, we evaluated the relationship between body composition (fat and lean mass) and bone mass in HIV-pos and HIV-neg children/youth and determined if it is modified by HIV status and sex. We used generalized estimating equations to simultaneously model the effect of fat/lean mass on multiple bone outcomes, including total body bone mineral density and bone mineral content and spine bone mineral density. We evaluated effect modification by HIV and sex.The analysis cohort consisted of 143 HIV-neg and 236 HIV-pos, of whom 55% were black non-Hispanic and 53% were male. Ages ranged from 7 to < 25 years. Half of the children/youth were at Tanner stage 1 and 20% at Tanner 5. Fat mass was more strongly positively correlated with bone mass in HIV-neg than HIV-pos children/youth and these relationships were more evident for total body bone than spine outcomes. Within HIV strata, fat mass and bone were more correlated in female than male children/youth. The relationship between lean mass and bone varied by sex, but not by HIV status.HIV disease diminishes the positive relationship of greater fat mass on bone mass in children/youth. Disruptions in body fat distribution, which are common in HIV disease, may have an impact on bone accretion during pubertal development.
Project description:BACKGROUND AND AIMS:ARC-520, the first an RNA interference (RNAi) therapeutic, was designed to reduce all RNA transcripts derived from covalently closed circular DNA, leading to a reduction in viral antigens and hepatitis B virus (HBV) DNA. APPROACH AND RESULTS:We aimed to evaluate the depth of hepatitis B surface antigen (HBsAg) decline in response to multiple doses of ARC-520 compared to placebo (PBO) in two randomized, multicenter studies in nucleoside/nucleotide analogue reverse-transcriptase inhibitor (NUC)-experienced patients with hepatitis B early antigen (HBeAg)-negative (E-neg) or HBeAg-positive (E-pos) disease. A total of 58 E-neg and 32 E-pos patients were enrolled and received four monthly doses of PBO (n = 20 E-neg, 11 E-pos), 1 mg/kg ARC-520 (n = 17 E-neg, 10 E-pos), or 2 mg/kg ARC-520 (n = 21 E-neg, 11 E-pos) concomitantly with NUC. HBsAg change from baseline to 30 days after the last ARC-520 dose were compared to PBO. Both E-neg and E-pos high-dose groups significantly reduced HBsAg compared to PBO, with mean reductions of 0.38 and 0.54 log IU/mL, respectively. HBsAg reductions persisted for approximately 85 days and >85 days after the last dose in E-neg and E-pos patients, respectively. The low-dose groups did not reach statistical significance in either study. E-pos patients showed a dose-dependent reduction in HBeAg from baseline. Mean maximum reduction was 0.23 and 0.69 log Paul Ehrlich IUs/mL in the low-dose and high dose ARC-520 groups respectively. ARC-520 was well tolerated, with only two serious adverse events of pyrexia possibly related to study drug observed. CONCLUSIONS:ARC-520 was active in both E-neg and E-pos, NUC-experienced HBV patients; but absolute HBsAg reductions were moderate, possibly due to expression of HBsAg from integrated HBV DNA, indicating the need for RNAi therapeutics that can target viral transcripts regardless of origin.
Project description:The regulation of mRNA translation is of fundamental importance in biological mechanisms ranging from embryonic axis specification to the formation of long-term memory. POS-1 is one of several CCCH zinc-finger RNA-binding proteins that regulate cell fate specification during C. elegans embryogenesis. Paradoxically, pos-1 mutants exhibit striking defects in endo-mesoderm development but have wild-type distributions of SKN-1, a key determinant of endo-mesoderm fates. RNAi screens for pos-1 suppressors identified genes encoding the cytoplasmic poly(A)-polymerase homolog GLD-2, the Bicaudal-C homolog GLD-3, and the protein NEG-1. We show that NEG-1 localizes in anterior nuclei, where it negatively regulates endo-mesoderm fates. In posterior cells, POS-1 binds the neg-1 3' UTR to oppose GLD-2 and GLD-3 activities that promote NEG-1 expression and cytoplasmic lengthening of the neg-1 mRNA poly(A) tail. Our findings uncover an intricate series of post-transcriptional regulatory interactions that, together, achieve precise spatial expression of endo-mesoderm fates in C. elegans embryos.
Project description:Identification of histone acetylation targets of Kat2a activity in murine models of acute myeloid leukemia (AML) driven by the MLL-AF9 oncogenic fusion Overall design: Pooled mouse bone marrow (BM) samples obtained from terminal primary MLL-AF9 AMLs established from Kat2a WT (Mx1-Cre NEG = label NEG) or Kat2a KO (Mx1-Cre POS = label POS) cells were analysed for H3K9 and H3K27 acetylation marks, as well as for H3K4me3 (marking active promoters) and H3K4me1 (marking enhancers). Experiments were performed in duplicate (R1 and R2), as independent cell samples and chromatin preparations from the same pools of animals.
Project description:Hopelessness is an important construct in psychosocial epidemiology, but there is great pressure on the length of questionnaire measures in large-scale population and clinical studies. We examined the validity and test-retest reliability of two brief measures of hopelessness, an existing negatively worded two-item measure of hopelessness (Brief-H-Neg) and a positively worded version of the same instrument (Brief-H-Pos).Cohort study.Control arm of the UK Collaborative Trial of Ovarian Cancer Screening.A non-clinical research-based sample of 5000 postmenopausal women selected from 56?512 participants.Spearman's rank correlation of brief measures of hopelessness with the Beck Hopelessness Scale (BHS). Spearman's rank correlation with the Centre for Epidemiological Studies Depression Scale (CES-D) and change in mean score on repeat testing.Two short hopelessness measures, a negatively worded brief measure of hopelessness (Brief-H-Neg) and a positively worded brief measure of hopelessness (Brief-H-Pos), were administered by postal questionnaire to 5000 women together with the 20-item BHS and 20-item CES-D. The Brief-H-Neg and Brief-H-Pos were readministered to 500 women after a 2-week interval.2413 postmenopausal women (mean age 68.9?years) completed the questionnaire. The Brief-H-Neg and Brief-H-Pos correlated 0.93 and 0.87 with the BHS after correction for attenuation and their association with the CES-D mirrored that seen with the BHS (Spearman's rank correlation 0.88 and 0.68, respectively). There was no change in mean scores on the two measures with repeat testing in the 433 women who completed them and test-retest reliability was good (intraclass correlations Brief-H-Neg 0.67 and Brief-H-Pos 0.72).These findings provide support for the validity of the Brief-H-Neg and Brief-H-Pos. These brief measures are likely to be useful in large population studies assessing hopelessness.NCT00058032.
Project description:Systemic inflammation is a characteristic of both HIV-1 infection and aging ("inflammaging"). Intestinal epithelial barrier damage (IEBD) and microbial translocation (MT) contribute to HIV-associated inflammation, but their impact on inflammaging remains unclear.Plasma biomarkers for IEBD (iFABP), MT (LPS, sCD14), T-cell activation (sCD27), and inflammation (hsCRP, IL-6) were measured in 88 HIV-1 uninfected (HIV(neg)) and 83 treated, HIV-1-infected (HIV(pos)) adults from 20-100 years old.Age positively correlated with iFABP (r = 0.284, p = 0.008), sCD14 (r = 0.646, p =?<0.0001) and LPS (r = 0.421, p = 0.0002) levels in HIV(neg) but not HIV(pos) subjects. Age also correlated with sCD27, hsCRP, and IL-6 levels regardless of HIV status. Middle-aged HIV(pos) subjects had elevated plasma biomarker levels similar to or greater than those of elderly HIV(neg) subjects with the exception of sCD14. Clustering analysis described an inflammaging phenotype (IP) based on iFABP, sCD14, sCD27, and hsCRP levels in HIV(neg) subjects over 60 years of age. The IP in HIV(neg) subjects was used to develop a classification model that was applied to HIV(pos) subjects to determine whether HIV(pos) subjects under 60 years of age were IP+. HIV(pos) IP+ subjects were similar in age to IP- subjects but had a greater risk of cardiovascular disease (CVD) based on Framingham risk score (p =? 0.01).We describe a novel IP that incorporates biomarkers of IEBD, MT, immune activation as well as inflammation. Application of this novel IP in HIV-infected subjects identified a group at higher risk of CVD.