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Obesity, a dysregulation of adipose tissue, is a major health risk factor associated with many diseases. Brown adipose tissue (BAT)-mediated thermogenesis can potentially regulate energy expenditure, making it an attractive therapeutic target to combat obesity. Here, we characterize the effects of cold exposure, thermoneutrality, and high-fat diet (HFD) feeding on mouse supraclavicular BAT (scBAT) morphology and BAT-associated gene expression compared to other adipose depots, including the interscapular BAT (iBAT). scBAT was as sensitive to cold induced thermogenesis as iBAT and showed reduced thermogenic effect under thermoneutrality. While both scBAT and iBAT are sensitive to cold, the expression of genes involved in nutrient processing is different. The scBAT also showed less depot weight gain and more single-lipid adipocytes, while the expression of BAT thermogenic genes, such as Ucp1, remained similar or increased more under our HFD feeding regime at ambient and thermoneutral temperatures than iBAT. Together, these findings show that, in addition to its anatomical resemblance to human scBAT, mouse scBAT possesses thermogenic features distinct from those of other adipose depots. Lastly, this study also characterizes a previously unknown mouse deep neck BAT (dnBAT) depot that exhibits similar thermogenic characteristics as scBAT under cold exposure and thermoneutrality.

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There is an increase in the prevalence of obesity and its related health problems. While dietary management and exercise help reduce the accumulation of body fat, recently attention has also been drawn to many medicinal herbs as the possible strategies for fat reduction in addition to medications. In the present study, we examined the effects of extracts from Trichosanthis Radix by ethanol (RE) or water (RW) on the differentiation of 3T3‐L1. Extracts were applied either during differentiation or after induction of cell differentiation for 8 days. We tested fat droplets accumulation by Oil Red O staining and triglyceride assay at the end of study. Treatment of differentiating 3T3‐L1 cells with RE or RW shows a significant decreased fat accumulation (% of reduction: RE 40%~50% and RW 50%~60%). Application of these extracts after the formation of adipocytes reduces fat accumulation to a lesser extent. To study the underlying mechanisms, we analyze the expressions of SRBP‐1, PPARγ and C/EBPα, which are important transcription factors for cell differentiation. Treatment of RW is able to reduce their expressions during early cell differentiation. In conclusion, these results indicate that water extracts of Trichosanthis Radix are more effective in inhibition of fat accumulation which is possible mediated through the decreased expressions of SRBP‐1, PPARγ and C/EBPα.

Introduction: Transcatheter aortic valve replacement has revolutionized the treatment of severe aortic stenosis, but post implantation perivalvular aortic regurgitation may result in increased mortality. Hypothesis: The purpose of this study was to identify structural abnormalities in the frame of self-expanding aortic valve prostheses (CoreValve®, Medtronic, Minneapolis, MN) immediately following implantation and evaluate their relationship to subsequent perivalvular aortic regurgitation severity. Methods/Results: After implantation of CoreValve, 14 patients with evidence of frame deformation by fluoroscopy underwent intraprocedural C-arm CT imaging (syngo DynaCT®, Siemens Medical Solutions, USA) acquired using 5-s, 200° rotation under breath-hold and rapid right ventricular pacing (120-140bpm). CT-like multi-planar reconstructions (Figure) were performed; perimeter (P), maximum (Dmax) and minimum (Dmin) diameters of the CoreValve frame were measured at multiple levels (0mm, 8mm, 16mm) orthogonal to the longitudinal axis. Ellipticity index (EI) was measured as Dmax divided by Dmin. Color Doppler transthoracic echo was performed the day following valve implantation to assess perivalvular regurgitation. One-way ANOVA demonstrated that degree of perivalvular aortic regurgitation was significantly related to valve frame perimeter underexpansion at the inferior margin of the frame (20.8% [17.2-25.7%], p=0.011) and increased ellipticity index both at the 8mm above the edge of the frame (1.4, [1.3-1.5], p=0.012) and 16mm above the edge of the frame (1.4, [1.3-1.5], p=0.038). Conclusions: Intraprocedural DynaCT effective at determining aortic valve frame deformations in 3D, which was associated with increased perivalvular aortic regurgitation, and may provide a method for risk stratifying post-implantation aortic regurgitation and need for additional procedural maneuvers such as post-stent dilation or additional revalving.