Recruited brown adipose tissue as an antiobesity agent in humans.

Brown adipose tissue (BAT) burns fat to produce heat when the body is exposed to cold and plays a role in energy metabolism. Using fluorodeoxyglucose-positron emission tomography and computed tomography, we previously reported that BAT decreases with age and thereby accelerates age-related accumulation of body fat in humans. Thus, the recruitment of BAT may be effective for body fat reduction. In this study, we examined the effects of repeated stimulation by cold and capsinoids (nonpungent capsaicin analogs) in healthy human subjects with low BAT activity. Acute cold exposure at 19°C for 2 hours increased energy expenditure (EE). Cold-induced increments of EE (CIT) strongly correlated with BAT activity independently of age and fat-free mass. Daily 2-hour cold exposure at 17°C for 6 weeks resulted in a parallel increase in BAT activity and CIT and a concomitant decrease in body fat mass. Changes in BAT activity and body fat mass were negatively correlated. Similarly, daily ingestion of capsinoids for 6 weeks increased CIT. These results demonstrate that human BAT can be recruited even in individuals with decreased BAT activity, thereby contributing to body fat reduction.

Grains of paradise (Aframomum melegueta) extract activates brown adipose tissue and increases whole-body energy expenditure in men.

Brown adipose tissue (BAT) is responsible for cold- and diet-induced thermogenesis, and thereby contributes to the control of whole-body energy expenditure (EE) and body fat content. BAT activity can be assessed by fluoro-2-deoxyglucose (FDG)-positron emission tomography (PET) in human subjects. Grains of paradise (GP, Aframomum melegueta), a species of the ginger family, contain pungent, aromatic ketones such as 6-paradol, 6-gingerol and 6-shogaol. An alcohol extract of GP seeds and 6-paradol are known to activate BAT thermogenesis in small rodents. The present study aimed to examine the effects of the GP extract on whole-body EE and to analyse its relation to BAT activity in men. A total of nineteen healthy male volunteers aged 20-32 years underwent FDG-PET after 2 h of exposure to cold at 19°C with light clothing. A total of twelve subjects showed marked FDG uptake into the adipose tissue of the supraclavicular and paraspinal regions (BAT positive). The remaining seven showed no detectable uptake (BAT negative). Within 4 weeks after the FDG-PET examination, whole-body EE was measured at 27°C before and after oral ingestion of GP extract (40 mg) in a single-blind, randomised, placebo-controlled, crossover design. The resting EE of the BAT-positive group did not differ from that of the BAT-negative group. After GP extract ingestion, the EE of the BAT-positive group increased within 2 h to a significantly greater (P<0·01) level than that of the BAT-negative group. Placebo ingestion produced no significant change in EE. These results suggest that oral ingestion of GP extract increases whole-body EE through the activation of BAT in human subjects.

Effect of the phytotherapeutic agent eviprostat on the bladder in a rat model of bladder overdistension/emptying.

AIMS: Ischemia-reperfusion injury is an important factor in the development of lower urinary tract symptoms (LUTS) that is partly mediated by the generation of free radicals. We investigate the effect of the phytotherapeutic agent Eviprostat, a treatment for benign prostatic hyperplasia (BPH) that has antioxidant and anti-inflammatory activity, on urinary bladder blood flow (BBF), and function in a rat model of bladder overdistension and emptying (OE). METHODS: For 8 days before surgery, OE rats received daily oral Eviprostat (36 mg/kg/day) or vehicle, while sham-operated animals received vehicle. The bladder was distended by infusion of saline over a period of 2 hr (overdistension) and then emptied. After 24 hr, BBF was measured with a laser speckle blood flow imager. The oxidative-stress marker malondialdehyde (MDA), proinflammatory cytokines, and myeloperoxidase were determined in the isolated bladder, and histological analysis was performed. Functional contractile responses of bladder strips to electrical field stimulation, carbachol, and KCl were measured. RESULTS: Twenty-four hours after bladder OE, a significant decrease in BBF and significant increases in bladder weight, malondialdehyde, proinflammatory cytokines, and myeloperoxidase were observed. Eviprostat almost completely prevented these changes. Histological analysis of the bladder of OE rats showed hemorrhage, accumulation of leukocytes, desquamation of epithelium, and edema, and Eviprostat suppressed these changes. The reduction in functional contractile forces in the bladder of OE rats was also prevented by Eviprostat. CONCLUSION: Eviprostat-mediated suppression of increased bladder oxidative stress and inflammation caused by bladder OE may contribute to the improvement of BBF and bladder function by Eviprostat.

Nonpungent capsaicin analogs (capsinoids) increase energy expenditure through the activation of brown adipose tissue in humans.

BACKGROUND: Capsinoids-nonpungent capsaicin analogs-are known to activate brown adipose tissue (BAT) thermogenesis and whole-body energy expenditure (EE) in small rodents. BAT activity can be assessed by [¹8F]fluorodeoxyglucose-positron emission tomography (FDG-PET) in humans. OBJECTIVES: The aims of the current study were to examine the acute effects of capsinoid ingestion on EE and to analyze its relation to BAT activity in humans. DESIGN: Eighteen healthy men aged 20-32 y underwent FDG-PET after 2 h of cold exposure (19°C) while wearing light clothing. Whole-body EE and skin temperature, after oral ingestion of capsinoids (9 mg), were measured for 2 h under warm conditions (27°C) in a single-blind, randomized, placebo-controlled, crossover design. RESULTS: When exposed to cold, 10 subjects showed marked FDG uptake into adipose tissue of the supraclavicular and paraspinal regions (BAT-positive group), whereas the remaining 8 subjects (BAT-negative group) showed no detectable uptake. Under warm conditions (27°C), the mean (±SEM) resting EE was 6114 ± 226 kJ/d in the BAT-positive group and 6307 ± 156 kJ/d in the BAT-negative group (NS). EE increased by 15.2 ± 2.6 kJ/h in 1 h in the BAT-positive group and by 1.7 ± 3.8 kJ/h in the BAT-negative group after oral ingestion of capsinoids (P < 0.01). Placebo ingestion produced no significant change in either group. Neither capsinoids nor placebo changed the skin temperature in various regions, including regions close to BAT deposits. CONCLUSION: Capsinoid ingestion increases EE through the activation of BAT in humans. This trial was registered at http://www.umin.ac.jp/ctr/ as UMIN 000006073.