Changes in protein fluxes and gene expression in non-injured muscle tissue distant from an acute myotoxic injury in male mice.

The response to acute myotoxic injury requires stimulation of local repair mechanisms in the damaged tissue. However, satellite cells in muscle distant from acute injury have been reported to enter a functional state between quiescence and active proliferation. Here, we asked whether protein flux rates are altered in muscle distant from acute local myotoxic injury and how they compare to changes in gene expression from the same tissue.

Changes in protein fluxes in skeletal muscle during sequential stages of muscle regeneration after acute injury in male mice.

Changes in protein turnover play an important role in dynamic physiological processes, including skeletal muscle regeneration, which occurs as an essential part of tissue repair after injury. The inability of muscle tissue to recapitulate this regenerative process can lead to the manifestation of clinical symptoms in various musculoskeletal diseases, including muscular dystrophies and pathological atrophy. Here, we employed a workflow that couples deuterated water (HO) administration with mass spectrometry (MS) to systematically measure in-vivo protein turnover rates across the muscle proteome in 8-week-old male C57BL6/J mice.

Altered extracellular matrix dynamics is associated with insulin resistance in adolescent children with obesity.

Objective: The objective of this study was to examine the hypothesis that abdominal and gluteal adipocyte turnover, lipid dynamics, and fibrogenesis are dysregulated among insulin-resistant (IR) compared with insulin-sensitive (IS) adolescents with obesity.

Methods: Seven IS and seven IR adolescents with obesity participated in a 3-h oral glucose tolerance test and a multi-section magnetic resonance imaging scan of the abdominal region to examine body fat distribution patterns and liver fat content. An 8-week 70% deuterated water ( H O) labeling protocol examined adipocyte turnover, lipid dynamics, and fibrogenesis in vivo from biopsied abdominal and gluteal fat.

Characterization of the Intraclonal Complexity of Chronic Lymphocytic Leukemia B Cells: Potential Influences of B-Cell Receptor Crosstalk with Other Stimuli.

Chronic lymphocytic leukemia (CLL) clones contain subpopulations differing in time since the last cell division ("age"): recently born, proliferative (PF; CXCR4CD5), intermediate (IF; CXCR4CD5), and resting (RF; CXCR4CD5) fractions. Herein, we used deuterium (H) incorporation into newly synthesized DNA in patients to refine the kinetics of CLL subpopulations by characterizing two additional CXCR4/CD5 fractions, i.e.

Selective decrease of donor-reactive T after liver transplantation limits T therapy for promoting allograft tolerance in humans.

Promoting immune tolerance to transplanted organs can minimize the amount of immunosuppressive drugs that patients need to take, reducing lifetime risks of mortality and morbidity. Regulatory T cells (T) are essential for immune tolerance, and preclinical studies have shown their therapeutic efficacy in inducing transplantation tolerance. Here, we report the results of a phase 1/2 trial (ARTEMIS, NCT02474199) of autologous donor alloantigen-reactive T (darT) therapy in individuals 2 to 6 years after receiving a living donor liver transplant.

HIV-1 Genomes Are Enriched in Memory CD4 T-Cells with Short Half-Lives.

Future HIV-1 curative therapies require a thorough understanding of the distribution of genetically-intact HIV-1 within T-cell subsets during antiretroviral therapy (ART) and the cellular mechanisms that maintain this reservoir. Therefore, we sequenced near-full-length HIV-1 genomes and identified genetically-intact and genetically-defective genomes from resting naive, stem-cell memory, central memory, transitional memory, effector memory, and terminally-differentiated CD4 T-cells with known cellular half-lives from 11 participants on ART. We find that a higher infection frequency with any HIV-1 genome was significantly associated with a shorter cellular half-life, such as transitional and effector memory cells.

Exercise reduced the formation of new adipocytes in the adipose tissue of mice in vivo.

Exercise has beneficial effects on metabolism and health. Although the skeletal muscle has been a primary focus, exercise also mediates robust adaptations in white adipose tissue. To determine if exercise affects in vivo adipocyte formation, fifty-two, sixteen-week-old C57BL/6J mice were allowed access to unlocked running wheels [Exercise (EX) group; n = 13 males, n = 13 females] or to locked wheels [Sedentary (SED) group; n = 13 males, n = 13 females] for 4-weeks.

Relationship between CD4 T cell turnover, cellular differentiation and HIV persistence during ART.

The precise role of CD4 T cell turnover in maintaining HIV persistence during antiretroviral therapy (ART) has not yet been well characterized. In resting CD4 T cell subpopulations from 24 HIV-infected ART-suppressed and 6 HIV-uninfected individuals, we directly measured cellular turnover by heavy water labeling, HIV reservoir size by integrated HIV-DNA (intDNA) and cell-associated HIV-RNA (caRNA), and HIV reservoir clonality by proviral integration site sequencing. Compared to HIV-negatives, ART-suppressed individuals had similar fractional replacement rates in all subpopulations, but lower absolute proliferation rates of all subpopulations other than effector memory (TEM) cells, and lower plasma IL-7 levels (p = 0.

Adipose depot-specific effects of 16 weeks of pioglitazone on in vivo adipogenesis in women with obesity: a randomised controlled trial.

Aims/hypothesis: In vitro and rodent studies suggest that pioglitazone, a thiazolidinedione, can promote adipogenesis in adipose tissue (AT); however, there is a lack of in vivo studies in humans to support these findings. The objectives of this randomised, placebo-controlled, parallel-arm trial were to test if pioglitazone stimulates in vivo adipogenesis in the subcutaneous adipose tissue depots and if these measures were related to metabolic health outcomes in women with obesity.

Methods: Forty-one healthy women with obesity (20 black; 21 white; 29 ± 6 years; BMI 32.

Human sebum requires de novo lipogenesis, which is increased in acne vulgaris and suppressed by acetyl-CoA carboxylase inhibition.

Sebum plays important physiological roles in human skin. Excess sebum production contributes to the pathogenesis of acne vulgaris, and suppression of sebum production reduces acne incidence and severity. We demonstrate that sebum production in humans depends on local flux through the de novo lipogenesis (DNL) pathway within the sebocyte.

An ANGPTL4-ceramide-protein kinase Cζ axis mediates chronic glucocorticoid exposure-induced hepatic steatosis and hypertriglyceridemia in mice.

Chronic or excess glucocorticoid exposure causes lipid disorders such as hypertriglyceridemia and hepatic steatosis. Angptl4 (angiopoietin-like 4), a primary target gene of the glucocorticoid receptor in hepatocytes and adipocytes, is required for hypertriglyceridemia and hepatic steatosis induced by the synthetic glucocorticoid dexamethasone. Angptl4 has also been shown to be required for dexamethasone-induced hepatic ceramide production.

Altered In Vivo Lipid Fluxes and Cell Dynamics in Subcutaneous Adipose Tissues Are Associated With the Unfavorable Pattern of Fat Distribution in Obese Adolescent Girls.

Patterns of abdominal fat distribution (for example, a high vs. low visceral adipose tissue [VAT]/[VAT + subcutaneous adipose tissue (SAT)] ratio), independent of obesity, during adolescence carry a high risk for insulin resistance and type 2 diabetes. Longitudinal follow-up of a cohort of obese adolescents has recently revealed that a high ratio (high VAT/[VAT + SAT]) is a major determinant of fatty liver and metabolic impairment over time, with these effects being more pronounced in girls than in boys.

Measurement of Leukemic B-Cell Growth Kinetics in Patients with Chronic Lymphocytic Leukemia.

Cell proliferation plays a central role in the pathogenesis of every neoplastic disease as well as many other types of illness. Labeling of newly replicated DNA with deuterium (H), a nonradioactive isotope of hydrogen, administered to the patients in drinking water (HO) is a safe and reliable method to measure the in vivo birth rates of cells. Here, we describe a protocol to measure chronic lymphocytic leukemia B-cell birth/proliferation and death rates over time using this approach.

ERβ activation in obesity improves whole body metabolism via adipose tissue function and enhanced mitochondria biogenesis.

Objective: Estrogens play a key role in the distribution of adipose tissue and have their action by binding to both estrogen receptors (ER), α and β. Although ERβ has a role in the energy metabolism, limited data of the physiological mechanism and metabolic response involved in the pharmacological activation of ERβ is available.

Methods: For clinical relevance, non-ovariectomized female mice were subjected to high fat diet together with pharmacological (DIP - 4-(2-(3,5-dimethylisoxazol-4-yl)-1H-indol-3-yl)phenol) interventions to ERβ selective activation.

Racial differences in in vivo adipose lipid kinetics in humans.

The storage of lipids in the form of triglycerides (TGs) and the de novo synthesis (lipogenesis) of fatty acids from nonlipid precursors [de novo lipogenesis (DNL)] are important functions of adipose tissue (AT) that influence whole-body metabolism. Yet, few studies have reported in vivo estimates of adipose lipid kinetics in humans. Fifty-two women with obesity (27 African-American and 25 Caucasian; 29.

Acetyl-CoA Carboxylase Inhibitor GS-0976 for 12 Weeks Reduces Hepatic De Novo Lipogenesis and Steatosis in Patients With Nonalcoholic Steatohepatitis.

Background & Aims: Increased de novo lipogenesis (DNL) contributes to the pathogenesis of nonalcoholic steatohepatitis (NASH). Acetyl-CoA carboxylase catalyzes the rate-limiting step in DNL. We evaluated the safety and efficacy of GS-0976, a small molecule inhibitor of acetyl-CoA carboxylase, in patients with NASH.

LRH-1 regulates hepatic lipid homeostasis and maintains arachidonoyl phospholipid pools critical for phospholipid diversity.

Excess lipid accumulation is an early signature of nonalcoholic fatty liver disease (NAFLD). Although liver receptor homolog 1 (LRH-1) (encoded by NR5A2) is suppressed in human NAFLD, evidence linking this phospholipid-bound nuclear receptor to hepatic lipid metabolism is lacking. Here, we report an essential role for LRH-1 in hepatic lipid storage and phospholipid composition based on an acute hepatic KO of LRH-1 in adult mice (LRH-1AAV8-Cre mice).

Origin and differentiation of human memory CD8 T cells after vaccination.

The differentiation of human memory CD8 T cells is not well understood. Here we address this issue using the live yellow fever virus (YFV) vaccine, which induces long-term immunity in humans. We used in vivo deuterium labelling to mark CD8 T cells that proliferated in response to the virus and then assessed cellular turnover and longevity by quantifying deuterium dilution kinetics in YFV-specific CD8 T cells using mass spectrometry.

Impact of Moderate Alcohol Discontinuation on Insulin Action and Secretion in Latinos With and Without Hepatitis C.

Background: Insulin resistance (IR) is associated with hepatitis C virus (HCV), and Latinos are both at risk of IR and are disproportionately affected by HCV. Moderate alcohol consumption improves insulin sensitivity and may modify HCV-associated IR. We investigated the impact of moderate alcohol discontinuation on insulin sensitivity and secretion in Latinos using direct measurements.

Effect of Weight Gain and Weight Loss on In Vivo Colonocyte Proliferation Rate in People with Obesity.

Objective: To evaluate the effects of diet-induced changes in energy balance and body weight on in vivo colonocyte fractional proliferation rates (FPR) in people with obesity.

Methods: In vivo colonocyte FPR was assessed in 31 men and women with obesity (BMI: 35.4 ± 4.

Specific Macronutrients Exert Unique Influences on the Adipose-Liver Axis to Promote Hepatic Steatosis in Mice.

Background & Aims: The factors that distinguish metabolically healthy obesity from metabolically unhealthy obesity are not well understood. Diet has been implicated as a determinant of the unhealthy obesity phenotype, but which aspects of the diet induce dysmetabolism are unknown. The goal of this study was to investigate whether specific macronutrients or macronutrient combinations provoke dysmetabolism in the context of isocaloric, high-energy diets.

Association of In Vivo Adipose Tissue Cellular Kinetics With Markers of Metabolic Health in Humans.

Context: Adipose tissue (AT) expansion occurs by hypertrophy and hyperplasia. Impaired hyperplasia, or adipogenesis, has been associated with obesity-related diseases.

Objective: We examined how in vivo adipogenesis in the subcutaneous abdominal (scABD) and femoral (scFEM) depots (via 8-week incorporation of deuterium) correlates with markers of metabolic health.

Differences in In Vivo Cellular Kinetics in Abdominal and Femoral Subcutaneous Adipose Tissue in Women.

The accumulation of fat in upper-body (abdominal) adipose tissue is associated with obesity-related cardiometabolic diseases, whereas lower-body (gluteal and femoral) fat may be protective. Studies suggest physiological and molecular differences between adipose depots and depot-specific cellular mechanisms of adipose expansion. We assessed in vivo cellular kinetics in subcutaneous adipose tissue from the abdominal (scABD) and femoral (scFEM) depots using an 8-week incorporation of deuterium ((2)H) from (2)H2O into the DNA of adipocytes and preadipocytes in 25 women with overweight or obesity.