Considerable evidence suggests that the time of day at which calories are consumed markedly impacts body weight gain and adiposity. However, a precise quantification of energy balance parameters ...during controlled animal studies enforcing time-of-day-restricted feeding is currently lacking in the absence of direct human interaction.
The purpose of the present study was therefore to quantify the effects of restricted feeding during the light (sleep)-phase in a fully-automated, computer-controlled comprehensive laboratory animal monitoring system (CLAMS) designed to modulate food access in a time-of-day-dependent manner. Energy balance, gene expression (within metabolically relevant tissues), humoral factors and body weight were assessed.
We report that relative to mice fed only during the dark (active)-phase, light (sleep)-phase fed mice: (1) consume a large meal upon initiation of food availability; (2) consume greater total calories per day; (3) exhibit a higher respiratory exchange ratio (indicative of decreased reliance on lipid/fatty acid oxidation); (4) exhibit tissue-specific alterations in the phases and amplitudes of circadian clock and metabolic genes in metabolically active tissues (greatest phase differences observed in the liver and diminution of amplitudes in epididymal fat, gastrocnemius muscle and heart); (5) exhibit diminished amplitude in humoral factor diurnal variations (for example, corticosterone); and (6) exhibit greater weight gain within 9 days of restricted feeding.
Collectively, these data suggest that weight gain following light (sleep)-phase restricted feeding is associated with significant alterations in energy balance, as well as dyssynchrony between metabolically active organs.
In obesity, rapidly expanding adipose tissue becomes hypoxic, precipitating inflammation, fibrosis, and insulin resistance. Compensatory angiogenesis may prevent these events. Mice lacking the ...intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1−/−) have “healthier” adipose tissue distribution and resist metabolic disease with diet-induced obesity. Here we show that adipose tissues of 11βHSD1−/− mice exhibit attenuated hypoxia, induction of hypoxia-inducible factor (HIF-1α) activation of the TGF-β/Smad3/α-smooth muscle actin (α-SMA) signaling pathway, and fibrogenesis despite similar fat accretion with diet-induced obesity. Moreover, augmented 11βHSD1−/− adipose tissue angiogenesis is associated with enhanced peroxisome proliferator-activated receptor γ (PPARγ)-inducible expression of the potent angiogenic factors VEGF-A, apelin, and angiopoietin-like protein 4. Improved adipose angiogenesis and reduced fibrosis provide a novel mechanism whereby suppression of intracellular glucocorticoid regeneration promotes safer fat expansion with weight gain.
Background: Adipose hypertrophy limits fat cell oxygenation, promotes scarring, and associates with increased local glucocorticoid regeneration (higher 11βHSD1 enzyme).
Results: 11βHSD1 knock-out mice have reduced scarring and better vascularization and oxygenation in their adipose tissue.
Conclusion: Elevated adipose 11βHSD1 contributes to obesity pathogenesis by suppressing adipose angiogenesis.
Significance: Enhancement of adipose oxygenation and vascularization is a novel therapeutic modality for 11βHSD1 inhibitors.
We evaluated the analgesic efficacy, safety and tolerability of a novel chemokine receptor 2 (CCR2) antagonist, AZD2423, in posttraumatic neuralgia. This was a double-blind, randomized, ...parallel-group, multicentre study. One hundred thirty-three patients with posttraumatic neuralgia were equally randomized to 28days' oral administration of 20mg AZD2423, 150mg AZD2423 or placebo. The primary efficacy variable was the change of average pain score from 5days at baseline to the last 5days of treatment, measured by a numerical rating scale (NRS, 0-10). The secondary efficacy measures included NRS worst pain score, patient global impression of change, pain interference on sleep and activity, and Neuropathic Pain Symptom Inventory (NPSI). The change of the NRS average pain score was not significantly different between treatment groups (AZD2423 20mg -1.54; AZD2423 150mg -1.53; placebo -1.44). There were trends towards larger reduction of NPSI total score and NPSI subscores for paroxysmal pain and paresthesia/dysesthesia by AZD2423 150mg compared to placebo. No other secondary efficacy variables differed between treatment groups. The frequency and type of adverse events for AZD2423 were similar to placebo. Increased plasma levels of chemokine ligand 2 and reduced mean levels of monocytes (-30% by AZD2423 150mg) suggested that the administrated doses of AZD2423 had interacted with the CCR2 target. The CCR2 antagonist AZD2423 demonstrated no efficacy on NRS average pain scores and most of the secondary pain variables. The NPSI data suggested possible effects on certain sensory components of pain. There were no major safety or tolerability concerns.
Background
While adherence to healthful dietary patterns has been associated with a lower risk of coronary artery disease (CAD) in the general population, limited data are available among US ...veterans. We tested the hypothesis that adherence to Dietary Approach to Stop Hypertension (DASH) food pattern is associated with a lower risk of developing CAD among veterans.
Methods and Results
We analyzed data on 153 802 participants of the Million Veteran Program enrolled between 2011 and 2016. Information on dietary habits was obtained using a food frequency questionnaire at enrollment. We used electronic health records to assess the development of CAD during follow‐up. Of the 153 802 veterans who provided information on diet and were free of CAD at baseline, the mean age was 64.0 (SD=11.8) years and 90.4% were men. During a mean follow‐up of 2.8 years, 5451 CAD cases occurred. The crude incidence rate of CAD was 14.0, 13.1, 12.6, 12.3, and 11.1 cases per 1000 person‐years across consecutive quintiles of Dietary Approach to Stop Hypertension score. Hazard ratios (95% confidence interval) for CAD were 1.0 (ref), 0.91 (0.84–0.99), 0.87 (0.80–0.95), 0.86 (0.79–0.94), and 0.80 (0.73–0.87) from the lowest to highest quintile of Dietary Approach to Stop Hypertension score controlling for age, sex, body mass index, race, smoking, exercise, alcohol intake, and statin use (P linear trend, <0.0001).
Conclusions
Our data are consistent with an inverse association between Dietary Approach to Stop Hypertension diet score and incidence of CAD among US veterans.
Large-scale multi-ethnic cohorts offer unprecedented opportunities to elucidate the genetic factors influencing complex traits related to health and disease among minority populations. At the same ...time, the genetic diversity in these cohorts presents new challenges for analysis and interpretation. We consider the utility of race and/or ethnicity categories in genome-wide association studies (GWASs) of multi-ethnic cohorts. We demonstrate that race/ethnicity information enhances the ability to understand population-specific genetic architecture. To address the practical issue that self-identified racial/ethnic information may be incomplete, we propose a machine learning algorithm that produces a surrogate variable, termed HARE. We use height as a model trait to demonstrate the utility of HARE and ethnicity-specific GWASs.
Familial hypercholesterolemia (FH) is characterized by inherited high levels of low-density lipoprotein cholesterol (LDL-C) and premature coronary heart disease (CHD). Over a thousand low-frequency ...variants in
and
have been implicated in FH but few have been examined at the population level. We aim to estimate the phenotypic effects of a subset of FH variants on LDL-C and clinical outcomes among 331,107 multi-ethnic participants.
We examined the individual and collective association between putatively pathogenic FH variants included on the MVP biobank array and the maximum LDL-C level over an interval of 15 years (maxLDL). We assessed the collective effect on clinical outcomes by leveraging data from 61.7 million clinical encounters.
We found 8 out of 16 putatively pathogenic FH variants with ≥30 observed carriers to be significantly associated with elevated maxLDL (9.4-80.2 mg/dL). Phenotypic effects were similar for European and African Americans despite substantial differences in carrier frequencies. Based on observed effects on maxLDL, we identified a total of 748 carriers (1:443) who had elevated maxLDL (36.5±1.4 mg/dL, p=1.2×10
), and higher prevalence of clinical diagnoses related to hypercholesterolemia and CHD in a phenome-wide scan. Adjusted for maxLDL, FH variants collectively associated with higher prevalence of CHD (odds ratio, 1.59 95% CI 1.36-1.86, p=1.1×10
) but not peripheral artery disease.
The distribution and phenotypic effects of putatively pathogenic FH variants were heterogeneous within and across variants. More robust evidence of genotype-phenotype associations of FH variants in multi-ethnic populations is needed to accurately infer at-risk individuals from genetic screening.
Corpus luteum formation is characterized by a period of extensive vascularization, as capillaries in the thecal layer of the collapsed follicle following ovulation invade the previously avascular ...granulosa layer. In order to study these processes in vitro we have developed an endothelial cell preparation from the specific microvasculature of the ovarian follicle. Follicular aspirates, obtained at oocyte collection for in-vitro fertilization (IVF), were filtered to obtain fragments of follicle wall. These were set in Matrigel and then cultured allowing the growth of capillary-like structures through the matrix. Upon emergence from the Matrigel the growing cells formed monolayers with the characteristic cobble-stone morphology of endothelial cells. Immunocytochemistry demonstrated the presence of a range of endothelial-specific markers including von Willebrand factor (vWF), Ulex europeus agglutinin (UEA)-1, CD31 and E-selectin, as well as VCAM-1, which is normally associated with stimulated endothelial cells. RT-PCR analysis showed the expression of two receptors for vascular endothelial growth factor (flt-1 and KDR), and the endothelial nitric oxide synthase, adding further evidence of their identity as human ovarian microvascular endothelial cells (HOMEC). Thus, the novel preparative procedure described now allows the generation of HOMEC cultures from readily available material resulting from IVF procedures.
Recent recognition that an autoimmune myocarditis may precede, and result in, dilated cardiomyopathy has focused attention on immune mechanisms of myocardial injury. In this paper, we describe a ...model of chronic autoimmune myocarditis in the Lewis rat. The production of myocarditis has been previously described by this group and in brief is accomplished by a single tail vein infusion of activated T cells specific for a 17-amino acid peptide from rat cardiac myosin. In this report, animals were followed for approximately 6 months post-T-cell infusion. Hearts from animals which received cardiac myosin specific T cells all showed extensive fibrosis associated with ongoing inflammation. Apoptosis, identified by TdT-mediated dUTP nick end labelling (TUNEL), was identified as a mode of myocyte death in hearts with acute and chronic myocarditis but not in age- and sex-matched controls. Immunohistochemistry was used to characterize the immune infiltrate and adhesion molecules in hearts with chronic myocarditis and these findings were compared to hearts with acute myocarditis. We propose that this rat model of chronic myocarditis mimics human disease, since inflammation results in ventricular dilatation and myocyte hypertrophy reminiscent of dilated cardiomyopathy. This model offers potential for further investigation of immune, functional and possible therapeutic aspects of autoimmune related cardiomyopathies.
Gene therapy in patients with cystic fibrosis may need to be commenced before the onset of lung disease which may be evident as early as 4 weeks after birth. We assessed the efficacy of cationic ...lipid-mediated transfer of a reporter gene, chloramphenicol acetyltransferase, in the growing murine and human respiratory tract. Gene expression was greater in adult mice (greater than 8 weeks old) compared with 9- and 16-day-old animals, despite a relatively greater proportion of complex delivered to the younger mice. Subsequent experiments compared 16-day-old and adult mice. Whilst higher gene expression occurred in the parenchyma compared with conducting airways in both groups, significantly greater expression was seen in the conducting airway of adult mice compared with 16-day-old animals. This expression persisted beyond 18 days in the adults but was undetectable in the younger group at this time-point. In an ex vivo model there was no difference in gene expression between the two groups. Further, no differences were observed in gene expression between growing (age 5 weeks to 14 years 8 months) and adult human lung tissue in either parenchyma or conducting airway. These data suggest age-dependent differences in gene transfer in vivo, which are not seen in an ex vivo setting. Proof-of-principle has been demonstrated for cationic-lipid mediated gene transfer to the growing human lung. Gene Therapy (2000) 7, 273-278.
In the rat, autoimmune myocarditis can be produced by the infusion of activated myosin peptide specific, CD4+, class II restricted, effector T cells. Whether antigen presenting cells (APCs), which ...interact with these effector T cells in the heart, are a fixed population of cells (resident dendritic, macrophage, or endothelial cells), or a dynamic bone marrow derived population has not yet been demonstrated in vivo. To study this question, bone marrow chimeras were generated using inbred Brown Norway (BN) rats, which are resistant to autoimmune myocarditis, and transplanting them after lethal irradiation with (Lewis×BN) F1 bone marrow. BN rats differ at both MHC loci from the susceptible inbred Lewis rats. Two months after bone marrow transplantation, chimeric animals received Lewis T cells specific for a myocarditogenic peptide antigen. To characterize the cardiac APCs, immunohistochemistry using a battery of antibodies including Lewis-specific and broadly reactive antibodies for both MHC class I and class II, was performed on chimeric hearts, with and without infused Lewis T cells, and non-transplanted BN control hearts.
All chimeric rats infused with allogeneic (Lewis), anti-cardiac myosin peptide effector T cells displayed the lesions of myocarditis. Myocarditis was not present in non-transplanted BN controls given either Lewis or F1 derived myocarditogenic T cells, nor in chimeric animals which did not receive myocarditogenic T cells, thus excluding graftvs host disease as the explanation for the inflammation in chimeric hearts with myocarditis. Marrow derived cells expressing both Lewis class I and class II MHC molecules were demonstrated on perivascular cells in the myocardium of all chimeric animals, and on infiltrating cells in chimeric animals with myocarditis. Cells expressing Lewis-specific MHC antigens were not detected in the non-transplanted BN controls. Furthermore, immunohistochemistry using broadly reactive antibodies demonstrated MHC class II on perivascular cells with a dendritic morphology in all hearts but not on endothelial cells or cardiac myocytes. These results support the hypothesis that in vivo, cardiac APCs which result in MHC class II restricted, T cell induced myocarditis are a dynamic bone marrow derived population and not a fixed population.
In order to address the potential requirement of MHC class I for the initiation of autoimmune myocarditis, myocarditogenic T cells derived from either Lewis or DA(RP) rats were infused into a member of the other strain. These strains share common MHC class II genes but differ at the MHC class I loci. Myocarditis identical to that produced in the syngeneic animal was successfully transferred by the MHC class I mismatched T cells, but only after the recipient animal's native immune system was mildly suppressed. These results further support the primary role for professional antigen presentation via MHC class II restriction to the effector T cells at the initiation of autoimmune myocarditis in the heart.
Together, these experiments confirm that activated effector T cells, in order to produce myocarditis, require MHC class II compatible APCs in the heart, that these APCs are bone marrow derived, and will endogenously take up and present local antigens in the target organ after bone marrow reconstitution.
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