Investigation of the significance of Oil Red O‐positive macrophage excess in bronchoalveolar lavage fluid during HIV infection

L. Lacoste‐Collin, G. Martin‐Blondel, C. Basset‐Léobon, V. Lauwers‐Cancès, D. d’Aure, J. Aziza, A. Berry, B Marchou, M.B. Delisle and M. Courtade‐Saïdi Investigation of the significance of Oil Red O‐positive macrophage excess in bronchoalveolar lavage fluid during HIV infection Objective: To assess the significance of increased levels of Oil Red O‐positive macrophages (ORO‐PM) in bronchoalveolar lavage fluids (BALFs) from HIV‐positive patients. Methods: Cytological data for seventy BALF samples from 66 consecutive HIV‐infected patients were analysed according to antiretroviral therapy regimen, presence of Pneumocystis jiroveci infection, blood CD4⁺T cell count, HIV‐1 viral load and plasma lipid levels. Non‐parametric tests were used to compare the values between groups. Results: The percentages of ORO‐PM were high in this group: 40% [6–80] (median [interquartile range]). They were positively correlated with the BALF total cell count, 21% [5–48.5] for <300 cells/mm³ and 60% [26.5–80] for >300 cells/mm³ (P < 0.01) but inversely correlated with the percentage of BALF lymphocytes, 50% [20–80] for <15% lymphocytes and 11.5% [2–47] for ≥15% lymphocytes (P < 0.01). Antiretroviral therapy with or without protease inhibitors, plasma lipid levels, HIV‐1 viral load, blood CD4⁺T cell count or presence of a Pneumocystis jiroveci infection were not correlated with the ORO‐PM status. Conclusion: Significantly increased numbers of ORO‐PM were correlated with high total cell counts and low lymphocyte counts in BALF, irrespective of disease activity or treatment. Extended work on a larger series of patients needs to be conducted.     

A Pilot Internet‐Based Behavioral Weight Loss Intervention with or without Commercially Available Portion‐Controlled Foods

Objective : To evaluate the short‐term impact of portion‐controlled food provision in combination with an Internet behavioral weight loss program on weight, blood cholesterol, and blood glucose levels. Design and Methods : Fifty participants, mean age 46 ± 10.7 years and mean body mass index 35.1 ± 3.8 kg/m², were randomized to one of two study groups, an Internet behavioral weight loss program (Internet‐alone; n = 25) or an Internet behavioral weight loss program plus a commercially available portion‐controlled diet (Internet + PCD; n = 25) for 12 weeks. Results : An intent‐to‐treat analysis found that the mean weight change in the Internet + PCD group was ?5.7 ± 5.6 kg and in the Internet‐alone group (n = 25) was ?4.1 ± 4.0 kg (P = 0.26). Participants in the Internet + PCD group achieved significantly greater improvements in blood glucose (?2.6 ± 5.7 vs. 1.4 ± 11.0 mg/dl; P = 0.05) and LDL cholesterol (?8.2 ± 18.0 vs. ?0.6 ± 21.0 mg/dl; P = 0.04), compared with Internet‐alone group. Conclusions : These data suggest that there may be short‐term clinical benefit in using a PCD in conjunction with a behavioral Internet‐based weight loss program to enhance weight loss and improve health indicators.     

Plasma Levels of Adiponectin,a Novel Adipocyte‐Derived Hormone,in Sleep Apnea**

Objective: Obstructive sleep apnea (OSA) is associated with obesity, sympathetic activation, systemic inflammation, and cardiovascular morbidity. Obesity, β‐adrenergic agonists, and inflammation are linked to decreased expression and/or secretion of an adipose tissue‐derived antiatherogenic hormone, adiponectin. The purpose of the study was to investigate whether OSA affected plasma levels of adiponectin, which might help explain OSA‐associated cardiovascular morbidity. Research Methods and Procedures: We randomly selected 68 otherwise healthy male subjects, either with moderate/severe OSA [apnea‐hypopnea index (AHI) ≥ 20; n = 35] or without OSA (AHI ≤ 5; n = 33). The diagnosis of OSA was made based on prospective full polysomnography. Adiponectin was measured before polysomnography between 8 and 10 PM . Results: AHI was higher in the OSA group (49.5 ± 4.4 vs. 2.9 ± 0.4 events/h; p < 0.001). OSA subjects were also more obese, with greater BMI (33 ± 1 vs. 30 ± 1; p = 0.016) and percentage body fat (29 ± 1% vs. 26 ± 1%; p = 0.030). Adiponectin levels were 7.67 ± 0.73 and 6.33 ± 0.51 μg/mL in the OSA and non‐OSA groups, respectively, and this difference was significant in covariate analysis (taking into account age, hemodynamic characteristics, measures of body fat, and OSA severity) (p = 0.009). After excluding from both groups the subjects with extreme BMI, such that the OSA and non‐OSA study cohorts had similar BMI and percentage body fat, subjects with OSA had significantly higher plasma adiponectin (8.49 ± 0.92 vs. 6.32 ± 0.55 μg/mL; p = 0.042), differences also evident in covariate analysis (p = 0.017). Discussion: Plasma adiponectin levels are elevated in otherwise healthy subjects with OSA. Therefore, low adiponectin is unlikely to explain the association between OSA and cardiovascular disease.     

Comparing total body lipid content of young‐of‐the‐year Steller sea lions among regions of contrasting population trends

Steller sea lion (Eumetopias jubatus) young‐of‐the‐year (YOY) are nutritionally dependent upon their dam through the majority of their first year. Several indices of body condition were measured in YOY 1.5–9 mo of age captured in Southeast Alaska (n = 122), the Gulf of Alaska (n = 182), and the Aleutian Islands (n = 38) to test the hypothesis that nutritional stress impacted the ability of adult female Steller sea lions to adequately nourish their late gestation YOY in the central Aleutian Islands in the early 2000s. Body mass (kg) and percent total body lipid content (%TBL) increased with age in all three regions of Alaska that were sampled (P < 0.05). Young‐of‐the‐year 7–9 mo of age were leaner in Southeast Alaska (27.6% ± 1.0%) and Gulf of Alaska (29.5% ± 0.8%) than in the Aleutian Islands (35.7% ± 1.2%, P < 0.001). Condition indices calculated from morphometric measures did not strongly predict the %TBL measured by isotope dilution. The trend for Aleutian Island YOY to have larger body mass and larger body fat reserves are counter to what would be expected if dams were unable to adequately provision their late lactation YOY due to inadequate food availability in the central Aleutian Islands.     

Use of Portion‐Controlled Entrees Enhances Weight Loss in Women

Objective: To determine the efficacy of a weight‐loss diet using packaged portion‐controlled entrees compared with a self‐selected diet based on the U.S. Department of Agriculture Food Guide Pyramid (FGP) (United States Department of Agriculture, Center for Nutrition Policy and Promotion, Washington, DC; 1996). Research Methods and Procedures: Sixty healthy women (BMI 26 to 40 kg/m²; 24 to 60 years old) were randomized into two intervention groups for an 8‐week parallel arm study. The portion‐controlled group consumed two frozen entrees daily, plus additional food servings from the FGP. The self‐selected diet group consumed a recommended number of servings from the FGP. Diets were designed to be the same in composition (55% carbohydrate, 25% protein, 20% fat) and energy level (1365 kcal). Each group met weekly to monitor compliance and take measures. Outcomes included weight, body composition by DXA, hip and waist circumference, blood pressure, fasting blood lipids, glucose, insulin, and C‐reactive protein. Significant differences were assessed using repeated measures ANOVA. Results: The portion‐controlled group (n = 26) experienced greater decreases in weight (5.6 ± 2.2 kg or 6.5% vs. 3.6 ± 2.5 kg or 4.2%), fat mass (3.6 ± 1.8 vs. 2.3 ± 1.4 kg), total cholesterol (24.4 ± 21.5 mg/dL or 12.4% vs. 13.0 ± 13.9 mg/dL or 6.7%), and fasting insulin (?1.8 ± 3.7 vs.+0.3 ± 3.8 μU/mL) than the self‐selected diet group (n = 27) (p < 0.05). Discussion: Consumption of portion‐controlled entrees resulted in greater losses of weight and fat, thereby reducing cardiovascular disease risk. Accurate portion control is an important factor in weight loss success, and use of packaged entrees is an effective method of achieving this.     

TNF‐α‐induced cardiomyocyte apoptosis contributes to cardiac dysfunction after coronary microembolization in mini‐pigs

This experimental study was designed to clarify the relationship between cardiomyocyte apoptosis and tumour necrosis factor‐alpha (TNF‐α) expression, and confirm the effect of TNF‐α on cardiac dysfunction after coronary microembolization (CME) in mini‐pigs. Nineteen mini‐pigs were divided into three groups: sham‐operation group (n = 5), CME group (n = 7) and adalimumab pre‐treatment group (n = 7; TNF‐α antibody, 2 mg/kg intracoronary injection before CME). Magnetic resonance imaging (3.0‐T) was performed at baseline, 6th hour and 1 week after procedure. Cardiomyocyte apoptosis was detected by cardiac‐TUNEL staining, and caspase‐3 and caspase‐8 were detected by RT‐PCR and immunohistochemistry. Furthermore, serum TNF‐α, IL‐6 and troponin T were analysed, while myocardial expressions of TNF‐α and IL‐6 were detected. Both TNF‐α expression (serum level and myocardial expression) and average number of apoptotic cardiomyocyte nuclei were significantly increased in CME group compared with the sham‐operation group. Six hours after CME, left ventricular end‐systolic volume (LVESV) was increased and the left ventricular ejection fraction (LVEF) was decreased in CME group. Pre‐treatment with adalimumab not only significantly improved LVEF after CME (6th hour: 54.9 ± 2.3% versus 50.4 ± 3.9%, P = 0.036; 1 week: 56.7 ± 4.2% versus 52.7 ± 2.9%, P = 0.041), but also suppressed cardiomyocyte apoptosis and the expression of caspase‐3 and caspase‐8. Meanwhile, the average number of apoptotic cardiomyocytes nuclei was inversely correlated with LVEF (r = ?0.535, P = 0.022). TNF‐α‐induced cardiomyocyte apoptosis is likely involved in cardiac dysfunction after CME. TNF‐α antibody therapy suppresses cardiomyocyte apoptosis and improves early cardiac function after CME.     

Adiponectin Levels during Low‐ and High‐Fat Eucaloric Diets in Lean and Obese Women

Objective: Adiponectin influences insulin sensitivity (S_I) and fat oxidation. Little is known about changes in adiponectin with changes in the fat content of eucaloric diets. We hypothesized that dietary fat content may influence adiponectin according to an individual's S_I. Research Methods and Procedures: We measured changes in adiponectin, insulin, glucose, and leptin in response to high‐fat (HF) and low‐fat (LF) eucaloric diets in lean (n = 10) and obese (n = 11) subjects. Obese subjects were further subdivided in relation to a priori S_I. Results: We found significantly higher insulin, glucose, and leptin and lower adiponectin in obese vs. lean subjects during both HF and LF. The mean group values of these measurements, including adiponectin (lean, HF 21.9 ± 9.8; LF, 20.8 ± 6.6; obese, HF 10.0 ± 3.3; LF, 9.5 ± 2.3 ng/mL; mean ± SD), did not significantly change between HF and LF diets. However, within the obese group, the insulin‐sensitive subjects had significantly higher adiponectin during HF than did the insulin‐resistant subjects. Additionally, the change in adiponectin from LF to HF diet correlated positively with the obese subjects’ baseline S_I. Discussion: Although in lean and obese women, group mean values for adiponectin did not change significantly with a change in fat content of a eucaloric diet, a priori measured S_I in obese subjects predicted an increase in adiponectin during the HF diet; this may be a mechanism that preserves S_I in an already obese group.     

Determination of manganese‐ and manganese‐containing fungicides with lucigenin–Tween‐20‐enhanced chemiluminescence detection

A flow‐injection (FI) method is reported for the determination of Mn(II), maneb and mancozeb fungicides based on the catalytic effect of Mn(II) on the oxidation of lucigenin and dissolved oxygen in a basic solution. The Tween‐20 surfactant has been reported for first time to enhance lucigenin chemiluminescence (CL) intensity in the presence of Mn(II) (53%) and maneb and mancozeb (89%). The calibration graphs were linear in the concentration range of 0.001–1.5 mg L^–1 (R² = 0.9982 (n = 11) with a limit of detection (S/N = 3) of 0.1 µg L^–1 for Mn(II) and 0.01–3.0 mg L^–1 [R² = 0.9989 and R² = 0.9992 (n = 6)] with a limit of detection (S/N =3) of 1.0 µg L^–1 for maneb and mancozeb respectively. Injection throughputs of 90 and 120 h^–1 for Mn(II) and maneb and mancozeb respectively, and relative standard deviations of 1.0–3.4% were obtained in the concentration range studied. The experimental variables, e.g., reagents concentrations, flow rates, sample volume, and photomultiplier tube voltage, were optimized and potential interferences were investigated. The analysis of Mn(II) in river water reference materials (SLRS‐4 and SLRS‐5) showed good agreement with the certified values incorporating an on‐line 8‐hydroxyquinoline chelating column in the manifold for removing interfering metal ions. Recoveries for maneb and mancozeb were in the range of 92 ± 5 to 104 ± 3% and 91 ± 2 to 100 ± 4% (n = 3) respectively. The effect of 30 other pesticides (fungicides, herbicides and insecticides) was also examined in the lucigenin–Tween‐20 CL system. Copyright © 2015 John Wiley & Sons, Ltd.     

Age‐specific vibrissae growth rates: A tool for determining the timing of ecologically important events in Steller sea lions

Steller sea lions (SSL; Eumetopias jubatus) grow their vibrissae continually, providing a multiyear record suitable for ecological and physiological studies based on stable isotopes. An accurate age‐specific vibrissae growth rate is essential for registering a chronology along the length of the record, and for interpreting the timing of ecologically important events. We utilized four methods to estimate the growth rate of vibrissae in fetal, rookery pup, young‐of‐the‐year (YOY), yearling, subadult, and adult SSL. The majority of vibrissae were collected from SSL live‐captured in Alaska and Russia between 2000 and 2013 (n = 1,115), however, vibrissae were also collected from six adult SSL found dead on haul‐outs and rookeries during field excursions to increase the sample size of this underrepresented age group. Growth rates of vibrissae were generally slower in adult (0.44 ± 0.15 cm/mo) and subadult (0.61 ± 0.10 cm/mo) SSL than in YOY (0.87 ± 0.28 cm/mo) and fetal (0.73 ± 0.05 cm/mo) animals, but there was high individual variability in these growth rates within each age group. Some variability in vibrissae growth rates was attributed to the somatic growth rate of YOY sea lions between capture events (P = 0.014, r² = 0.206, n = 29).     

Increased 4‐hydroxy‐2‐nonenal‐induced proteasome dysfunction is correlated with cardiac damage in streptozotocin‐injected rats with isoproterenol infusion

Increase in 4‐hydroxy‐2‐nonenal (4HNE) due to oxidative stress has been observed in a variety of cardiac diseases such as diabetic cardiomyopathy. 4HNE exerts a damaging effect in the myocardium by interfering with subcellular organelles like mitochondria by forming adducts. Therefore, we hypothesized that increased 4HNE adduct formation in the heart results in proteasome inactivation in isoproterenol (ISO)‐infused type 1 diabetes mellitus (DM) rats. Eight‐week‐old male Sprague Dawley rats were injected with streptozotocin (STZ, 65 mg kg^?1). The rats were infused with ISO (5 mg kg^?1) for 2 weeks by mini pumps, after 8 weeks of STZ injection. We studied normal control (n = 8) and DM + ISO (n = 10) groups. Cardiac performance was assessed by echocardiography and Millar catheter at the end of the protocol at 20 weeks. Initially, we found an increase in 4HNE adducts in the hearts of the DM + ISO group. There was also a decrease in myocardial proteasomal peptidase (chymotrypsin and trypsin‐like) activity. Increases in cardiomyocyte area (446 ± 32·7 vs 221 ± 10·83) (µm²), per cent area of cardiac fibrosis (7·4 ± 0·7 vs 2·7 ± 0·5) and cardiac dysfunction were also found in DM + ISO (P < 0·05) relative to controls. We also found increased 4HNE adduct formation on proteasomal subunits. Furthermore, reduced aldehyde dehydrogenase 2 activity was observed in the myocardium of the DM + ISO group. Treatment with 4HNE (100 μM) for 4 h on cultured H9c2 cardiomyocytes attenuated proteasome activity. Therefore, we conclude that the 4HNE‐induced decrease in proteasome activity may be involved in the cardiac pathology in STZ‐injected rats infused with ISO. Copyright © 2016 John Wiley & Sons, Ltd.     

Quality of Life after Lap‐Band Placement: Influence of Time,Weight Loss,and Comorbidities

Objective: To assess the quality of life (QOL) in severely obese subjects before and after Lap‐Band gastric restrictive surgery and identify factors that may influence change. Research Methods and Procedures: All patients, over a 3‐year period, attending for preoperative assessment (n = 459) or annual review after surgery (n = 641) have completed the Short Form‐36 (SF‐36) health survey. Eight domain and physical component summary (PCS) and mental component summary (MCS) scores were calculated. Scores were analyzed in groups based on time after surgery and compared with community normal (CN) values. Paired preoperative and 1‐year scores (n = 218) data were used to find predictors of QOL change. Results: All preoperative mean scores (n = 459) were lower than CN values, with greater impairment in the PCS (36.8 ± 9.5 vs. CN: 51.3 ± 8.3, p < 0.001) than in the MCS (45.7 ± 8.2 vs. CN: 48.8 ± 9.5, p < 0.001) scores. After 1 year, scores were closer to CN scores (PCS: 52.4 ± 8.2 and MCS: 48.4 ± 7.7), and these remained closer for 4 years. Preoperative obesity comorbidity, especially physical disability, was the best predictor of poor preoperative SF‐36 scores and of improvement in scores at 1 year. The percentage of excess weight loss at 1 year (46 ± 16%) was of little predictive value of improved QOL. Discussion: Severely obese subjects have poor health‐related QOL as measured by the SF‐36 health survey. Lap‐Band surgery for this group has provided a dramatic and sustained improvement in all measures of the SF‐36. Improvement is greater in those with greater preoperative disability, and the extent of weight loss is not a good predictor of improved QOL.     

Triglyceride‐to‐HDL‐cholesterol Ratio and Metabolic Syndrome as Contributors to Cardiovascular Risk in Overweight Patients

Insulin resistance increases cardiovascular risk of obese patients. Triglyceride to high‐density lipoprotein cholesterol ratio (TG/HDL) ≥3.0 (in mg/dl) is a marker of insulin resistance in overweight persons. We aimed at assessing cardiovascular risk profile in 301 overweight elderly Neapolitan outpatients, according to TG/HDL ratio and metabolic syndrome (MS), diagnosed by National Cholesterol Education Program (NCEP) and International Diabetes Federation (IDF) criteria. TG/HDL ratio was ≥3.0 in 97 patients (group A) and <3.0 in 204 (group B). Overall, 93–97% of group A patients and 38–51% of group B patients had MS, depending on the diagnostic criterion. Group A patients with MS had significantly higher waist‐to‐hip ratio, total and non‐HDL cholesterol than group B patients with MS. In group B, MS and non‐MS patients had similar waist‐to‐hip ratio, blood pressure, total and non‐HDL cholesterol. Ten year coronary risk, calculated by the Framingham equations (n = 243), was 10.3 ± 5% in group B, non‐MS patients; 13.1 ± 6% in group B, MS patients; 19.9 ± 8% in group A (F = 32.8; P < 0.001). At the multiple regression analysis, TG/HDL ratio was associated with coronary risk (r² = 0.227) more closely than gender, blood pressure, waist‐to‐hip ratio, non HDL cholesterol, and MS considered as a whole. A separate regression analysis showed that the logarithmically transformed TG/HDL ratio, an index of the HDL cholesterol esterification rate, is also associated with coronary risk (r² = 0.252). Thus, TG/HDL ratio could help to characterize high‐risk overweight patients deserving a special therapeutic effort. Cardiovascular risk profile of insulin‐sensitive patients, identified by lower values of this parameter, is only moderately affected by MS.     

Adiposity in Middle‐aged Women is Associated with Genetic Taste Blindness to 6‐n‐Propylthiouracil

Objective: Taste blindness to the bitterness of 6‐n‐propylthiouracil (PROP) may be a genetic marker for food preferences and dietary choices that ultimately influence body weight. A previous study in middle‐aged women showed that those who were taste blind to PROP (i.e., nontasters) had higher BMIs than those with the greatest sensitivity to PROP (i.e., supertasters). This study tested the hypothesis that the nontaster phenotype was associated with greater adiposity in middle‐aged women. Research Methods and Procedures: Forty women with a mean BMI of 26.6 ± 1.3 kg/m² and a mean age of 41.8 ± 1.8 years were recruited from the local community. They were classified as nontasters (n = 8), medium tasters (n = 18), or supertasters (n = 14) of PROP using a filter paper screening procedure. Anthropometric measures included height, weight, body fatness, triceps skinfold thickness, and waist circumference. Dietary restraint and disinhibition were also measured to assess cognitions associated with body weight. Results: BMI was 6.2 units higher in nontaster women compared with supertaster women (29.7 ± 0.9 vs. 23.5 ± 0.9, respectively; p < 0.05). Body fatness (p < 0.01) and triceps skinfold thickness (p < 0.05) were also higher in these women. Waist circumference showed a trend in the appropriate direction. Although disinhibition was associated with greater adiposity, the relation between PROP status and adiposity was not altered after controlling for disinhibition. Discussion: The PROP nontaster phenotype was strongly associated with several measures of adiposity in middle‐aged women. These data confirm our previous findings and suggest that the PROP polymorphism may be a reliable indicator of weight gain susceptibility.     

The application of anti‐ESAT‐6 monoclonal antibody fluorescent probe in ex vivo near‐infrared fluorescence imaging in mice with pulmonary tuberculosis

Here, we aimed to assess the feasibility of anti‐ESAT‐6 monoclonal antibody (mAb) coupling with IR783 and rhodamine fluorescent probe in the detection of ESAT‐6 expression in tuberculosis tissue of mice using near‐infrared fluorescence imaging. IR783 and rhodamine were conjugated to the anti‐ESAT‐6 mAb or IgG. Mice in the experimental group were injected with fluorescence‐labeled mAb probe, and mice in the control group were injected with fluorescence‐labeled non‐specific IgG antibody. Twenty‐four hours later, the lung tissue of mice was examined using ex vivo near‐infrared fluorescence imaging. In addition, the contrast‐to‐noise ratio (CNR) was calculated by measuring the signal intensities of the pulmonary lesions, normal lung tissue and background noise. The frozen lung tissue section was examined under fluorescence microscopy and compared with hemoxylin and eosin (HE) staining. The ex vivo near‐infrared fluorescence imaging showed that the fluorescence signal in the lung tuberculosis lesions in the experimental group was significantly enhanced, whereas there was only a weak fluorescence signal or even no fluorescence signal in the control group. CNR values were 64.40 ± 7.02 (n = 6) and 8.75 ± 3.87 (n = 6), respectively (t = 17.01, p < 0.001). The fluorescence accumulation distribution detected under fluorescence microscopy was consistent with HE staining of the tuberculosis region. In conclusion, anti‐ESAT‐6 mAb fluorescent probe could target and be applied in specific ex vivo imaging of mice tuberculosis, and may be of further use in tuberculosis in living mice. Copyright © 2013 John Wiley & Sons, Ltd.     

Interstitial telomere‐like repeats in the monocot family Araceae

Combining molecular cytogenetics and phylogenetic modelling of chromosome number change can shed light on the types of evolutionary changes that may explain the haploid numbers observed today. Applied to the monocot family Araceae, with chromosome numbers of 2n = 8 to 2n = 160, this type of approach has suggested that descending dysploidy has played a larger role than polyploidy in the evolution of the current chromosome numbers. To test this, we carried out molecular cytogenetic analyses in 14 species from 11 genera, using probes for telomere repeats, 5S rDNA and 45S rDNA and a plastid phylogenetic tree covering the 118 genera of the family, many with multiple species. We obtained new chromosome counts for six species, modelled chromosome number evolution using all available counts for the family and carried out fluorescence in situ hybridization with three probes (5S rDNA, 45S rDNA and Arabidopsis‐like telomeres) on 14 species with 2n = 14 to 2n = 60. The ancestral state reconstruction provides support for a large role of descending dysploidy in Araceae, and interstitial telomere repeats (ITRs) were detected in Anthurium leuconerum, A. wendlingeri and Spathyphyllum tenerum, all with 2n = 30. The number of ITR signals in Anthurium (up to 12) is the highest so far reported in angiosperms, and the large repeats located in the pericentromeric regions of A. wendlingeri are of a type previously reported only from the gymnosperms Cycas and Pinus. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 15–26.     

Endothelial function and weight loss: Comparison of low‐carbohydrate and low‐fat diets

Objective: The effect of weight loss on obesity‐associated endothelial dysfunction is not clear because of conflicting data, demonstrating both improvement and no change in endothelial function after weight loss in obese subjects. A 2‐year prospective study (n = 121) was conducted to examine: (1) the effect of obesity and weight loss (either a low‐carbohydrate or and low‐fat diet) on flow mediated vasodilatation (FMD), a measure of endothelial function. Design and Methods: Participants reduced body weight by 7.1% ± 4.4%, 8.7% ± 6.8%, 7.1% ± 7.8%, and 4.1% ± 7.7% at 3, 6, 12, and 24 months, respectively with no significant differences between the low‐fat and low‐carbohydrate groups. Results: Endothelial function was inversely correlated with waist circumference, triglyceride level, and directly correlated with leptin in obese persons prior to weight loss. These weight losses did not confer any improvements in FMD. There were no differences between the low‐fat and low‐carbohydrate diets in FMD at any time point. At 6 months (r = 0.26, P = 0.04) and 1 year (r =0.28, P = 0.03), there were positive correlations between change in FMD and change in leptin but not at 2 years. Conclusion: There was no significant improvement in endothelial function after 7.1% ± 7.8% weight loss at 1 year and 4.1% ± 7.7% at 2 years, achieved by either a low carbohydrate or a low fat diet.     

Exercise‐Induced Reduction in Obesity and Insulin Resistance in Women: a Randomized Controlled Trial

Objectives : To determine the effects of equivalent diet‐ or exercise‐induced weight loss and exercise without weight loss on subcutaneous fat, visceral fat, and insulin sensitivity in obese women. Research Methods and Procedures : Fifty‐four premenopausal women with abdominal obesity [waist circumference 110.1 ± 5.8 cm (mean ± SD)] (BMI 31.3 ± 2.0 kg/m²) were randomly assigned to one of four groups: diet weight loss (n = 15), exercise weight loss (n = 17), exercise without weight loss (n = 12), and a weight‐stable control group (n = 10). All groups underwent a 14‐week intervention. Results : Body weight decreased by ～6.5% within both weight loss groups and was unchanged in the exercise without weight loss and control groups. In comparison with controls, cardiorespiratory fitness improved within the exercise groups only (p < 0.01). Reduction in total, abdominal, and abdominal subcutaneous fat within the exercise weight loss group was greater (p < 0.001) than within all other groups. The reduction in total and abdominal fat within the diet weight loss and exercise without weight loss groups was greater than within controls (p < 0.001) but not different from each other (p > 0.05). Visceral fat decreased within all treatment groups (p < 0.008), and these changes were not different from each other. In comparison with the control group, insulin sensitivity improved within the exercise weight loss group alone (p < 0.001). Discussion : Daily exercise without caloric restriction was associated with substantial reductions in total fat, abdominal fat, visceral fat, and insulin resistance in women. Exercise without weight loss was also associated with a substantial reduction in total and abdominal obesity.     

Treadmill desks: A 1‐year prospective trial

Objective: Sedentariness is associated with weight gain and obesity. A treadmill desk is the combination of a standing desk and a treadmill that allow employees to work while walking at low speed. Design and Methods: The hypothesis was that a 1‐year intervention with treadmill desks is associated with an increase in employee daily physical activity (summation of all activity per minute) and a decrease in daily sedentary time (zero activity). Employees (n = 36; 25 women, 11 men) with sedentary jobs (87 ± 27 kg, BMI 29 ± 7 kg/m², n = 10 Lean BMI < 25 kg/m², n = 15 Overweight 25 < BMI < 30 kg/m², n = 11 Obese BMI > 30 kg/m²) volunteered to have their traditional desk replaced with a treadmill desk to promote physical activity for 1 year. Results: Daily physical activity (using accelerometers), work performance, body composition, and blood variables were measured at Baseline and 6 and 12 months after the treadmill desk intervention. Subjects who used the treadmill desk increased daily physical activity from baseline 3,353 ± 1,802 activity units (AU)/day to, at 6 months, 4,460 ± 2,376 AU/day (P < 0.001), and at 12 months, 4,205 ± 2,238 AU/day (P < 0.001). Access to the treadmill desks was associated with significant decreases in daily sedentary time (zero activity) from at baseline 1,020 ± 75 min/day to, at 6 months, 929 ± 84 min/day (P < 0.001), and at 12 months, 978 ± 95 min/day (P < 0.001). For the whole group, weight loss averaged 1.4 ± 3.3 kg (P < 0.05). Weight loss for obese subjects was 2.3 ± 3.5 kg (P < 0.03). Access to the treadmill desks was associated with increased daily physical activity compared to traditional chair‐based desks; their deployment was not associated with altered performance. For the 36 participants, fat mass did not change significantly, however, those who lost weight (n = 22) lost 3.4 ± 5.4 kg (P < 0.001) of fat mass. Weight loss was greatest in people with obesity. Conclusions: Access to treadmill desks may improve the health of office workers without affecting work performance.     

Obesity‐susceptibility loci and the tails of the pediatric BMI distribution

Objective: To determine whether previously identified adult obesity susceptibility loci were associated uniformly with childhood BMI across the BMI distribution. Design and Methods: Children were recruited through the Children's Hospital of Philadelphia (n = 7,225). Associations between the following loci and BMI were assessed using quantile regression: FTO (rs3751812), MC4R (rs12970134), TMEM18 (rs2867125), BDNF (rs6265), TNNI3K (rs1514175), NRXN3 (rs10146997), SEC16B (rs10913469), and GNPDA2 (rs13130484). BMI z‐score (age and gender adjusted) was modeled as the dependent variable, and genotype risk score (sum of risk alleles carried at the 8 loci) was modeled as the independent variable. Results: Each additional increase in genotype risk score was associated with an increase in BMI z‐score at the 5th, 15th, 25th, 50th, 75th, 85th, and 95th BMI z‐score percentiles by 0.04 (±0.02, P = 0.08), 0.07 (±0.01, P = 9.58 × 10^?7), 0.07 (±0.01, P = 1.10 × 10^?8), 0.09 (±0.01, P = 3.13 × 10^?22), 0.11 (±0.01, P = 1.35 × 10^?25), 0.11 (±0.01, P = 1.98 × 10^?20), and 0.06 (±0.01, P = 2.44 × 10^?6), respectively. Each additional increase in genotype risk score was associated with an increase in mean BMI z‐score by 0.08 (±0.01, P = 4.27 × 10^?20). Conclusion: Obesity risk alleles were more strongly associated with increases in BMI z‐score at the upper tail compared to the lower tail of the distribution.     

Maté Tea Inhibits In Vitro Pancreatic Lipase Activity and Has Hypolipidemic Effect on High‐fat Diet‐induced Obese Mice

The inhibitory effects of maté tea (MT), a beverage produced with leaves from Ilex paraguariensis, in vitro lipase activity and on obesity in obese mice models were examined. For the in vitro experiment, porcine and human pancreatic lipase (PL) activities were determined by measuring the rate of release of oleic acid from hydrolysis of olive oil emulsified with taurocholate, phospholipids, gum arabic, or polyvinyl alcohol. For the in vivo experiments, animals were fed with a standard diet (SD, n = 10) or high‐fat diet (HFD, n = 30) for 16 weeks. After the first 8 weeks on the HFD, the animals were treated with 1 and 2 g/kg of body weight of MT. The time course of the body weight and obesity‐related biochemical parameters were evaluated. The results showed that MT inhibited both porcine and human PL (half‐maximal inhibitory concentration = 1.5 mg MT/ml) and induced a strong inhibition of the porcine lipase activity in the hydrolysis of substrate emulsified with taurocholate + phosphatidylcholine (PC) (83 ± 3.8%) or PC alone (62 ± 4.3%). MT suppressed the increases in body weight (P < 0.05) and decreased the serum triglycerides and low‐density lipoprotein (LDL)‐cholesterol concentrations at both doses (from 190.3 ± 5.7 to 135.0 ± 8.9 mg/dl, from 189.1 ± 7.3 to 129.3 ± 17.6 mg/dl; P < 0.05, respectively) after they had been increased by the HFD. The liver lipid content was also decreased by the diet containing MT (from 132.6 ± 3.9 to 95.6 ± 6.1 mg/g of tissue; P < 0.05). These results suggest that MT could be a potentially therapeutic alternative in the treatment of obesity caused by a HFD.