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Brown adipose tissue (BAT) is responsible for non-shivering thermogenesis and is an attractive therapeutic target for combating obesity and related diseases. Human BAT activity has been evaluated by 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography ( 18 FDG-PET/CT) under acute cold exposure, but the method has some serious limitations, including radiation exposure. Infrared thermography (IRT) may be a simple and less-invasive alternative to evaluate BAT activity. In the present study, to establish an optimal condition for IRT, using a thermal imaging camera, skin temperature was measured in the supraclavicular region close to BAT depots (T scv ) and the control chest region (T c ) in 24 young healthy volunteers. Their BAT activity was assessed as the maximal standardized uptake value (SUV max ) by 18 FDG-PET/CT. Under a warm condition at 24–27°C, no significant correlation was found between the IRT parameters (T scv , T c, , and the difference between T scv and T c, , Δtemp) and SUV max , but 30–120 min after cold exposure at 19°C, T scv and Δtemp were significantly correlated with SUV max ( r = 0.40–0.48 and r = 0.68–0.76). Δtemp after cold exposure was not affected by mean body temperature, body fatness, and skin blood flow. A lower correlation ( r = 0.43) of Δtemp with SUV max was also obtained when the participant’s hands were immersed in water at 18°C for 5 min. Receiver operating characteristic analysis revealed that Δtemp after 30–60 min cold exposure can be used as an index for BAT evaluation with 74% sensitivity, 92% specificity, and 79% diagnostic accuracy. Thus, IRT may be useful as a simple and less-invasive method for evaluating BAT, particularly for large-scale screening and longitudinal repeat studies.

Background/objectives Disturbed circadian rhythm is associated with an increased risk of obesity and metabolic disorders. Brown adipose tissue (BAT) is a site of nonshivering thermogenesis (NST) and plays a role in regulating whole-body energy expenditure (EE), substrate metabolism, and body fatness. In this study, we examined diurnal variations of NST in healthy humans by focusing on their relation to BAT activity. Methods Forty-four healthy men underwent 18F-fluoro-2-deoxy-D-glucose positron emission tomography and were divided into Low-BAT and High-BAT groups. In STUDY 1, EE, diet-induced thermogenesis (DIT), and fat oxidation (FO) were measured using a whole-room indirect calorimeter at 27 °C. In STUDY 2, EE, FO, and skin temperature in the region close to BAT depots (Tscv) and in the control region (Tc) were measured at 27 °C and after 90 min cold exposure at 19 °C in the morning and in the evening. Results In STUDY 1, DIT and FO after breakfast was higher in the High-BAT group than in the Low-BAT group (P < 0.05), whereas those after dinner were comparable in the two groups. FO in the High-BAT group was higher after breakfast than after dinner (P < 0.01). In STUDY 2, cold-induced increases in EE (CIT), FO, and Tscv relative to Tc in the morning were higher in the High-BAT group than in the Low-BAT group (P < 0.05), whereas those after dinner were comparable in the two groups. CIT in the High-BAT group tended to be higher in the morning than in the evening (P = 0.056). Conclusion BAT-associated NST and FO were evident in the morning, but not in the evening, suggesting that the activity of human BAT is higher in the morning than in the evening, and thus may be involved in the association of an eating habit of breakfast skipping with obesity and related metabolic disorders.

Abstract. Oxidative stress and inflammation are known to play roles in the pathogenesis of vascular events. The aim of this study was to investigate the relationship between oxidative stress, inflammation, and atherosclerosis in the general population. A population-based, cross-sectional study was made of 282 people (126 men and 156 women, mean age; 65 ± 13, mean BMI; 25.4 ± 2.7 kg/m 2 ) recruited from the Mima study in Tokushima Prefecture. Risk factors included age, sex, body mass index (BMI), cigarette smoking, systolic and diastolic pressure, fasting blood glucose, serum lipids, and high-sensitive C-reactive protein (hs-CRP). Oxidative stress in blood samples was measured by the diacron reactive oxygen metabolites (ROMs) test. The degree of sclerotic change was determined from fundus photographs according to Scheie's classification. After adjustment for age and sex, ROM levels positively correlated with hs-CRP levels, but not with ghrelin, leptin and adiponectin levels. Furthermore, ROM and hs-CRP levels positively and individually correlated with the grade of sclerotic change in the fundus oculi independent of age in a multiple regression analysis. These results suggest that oxidative stress and chronic inflammation promote atherosclerosis in the retinal arteries in the general population.

BackgroundResidents of rural communities are often more socially connected compared to urban dwellers. Using family and community support to motivate health behavior change may be useful in rural settings. The objective of this study was to pilot a salt reduction (SR) intervention for rural albuminuria patients using support from family and neighborhood residents compared to a usual care condition. The primary outcome was change in urine albumin-creatinine ratio (ACR).MethodsAll consecutive outpatients with an ACR >= 30 mg/gCr were recruited from the Koyadaira Clinic. Patients self-selected their participation in the intervention group (IG) or the control group (CG) because the rural population expressed concern about not being treated at the same time. In the IG, patients and their families were educated in SR for 30 minutes in their home by experienced dieticians. In addition, patients, families and neighborhood residents were also educated in SR for 2 hours at a public town meeting hall, with educational content encouraging reduction in salt intake through interactive activity. The CG received conventional treatment, and ACR and blood pressure (BP) were measured after 3 months.ResultsOf the 37 subjects recruited (20 male, 16 female, mean age; 72.8 ± 9.2 years), 36 completed the 3-month follow up and were analyzed. In the IG, ACR decreased significantly from baseline (706 ± 1,081 to 440 ± 656; t = 2.28, p = 0.04) and was reduced compared to the CG (213 ± 323 to 164 ± 162; F = 3.50, p = 0.07), a treatment effect approaching significance. Systolic BP in the IG (145 ± 14 to 131 ± 13 mmHg; t = 3.83, p = 0.002) also decreased significantly compared to the CG (135 ± 13 to 131 ± 14; F = 4.40, p = 0.04).ConclusionsSimultaneous education of patients, their families and neighborhood residents may be important in rural areas for treatments and interventions requiring health behavior change.Trial registrationUMIN000001972