OBJECTIVES: To investigate the implications of Dermosonic lipoclasis (DLC), i.e. lipolysis on subcutaneous white adipose tissue induced by ultrasound, for the energy metabolism and body composition of healthy rats. METHODS: Twenty four-month-old male Wistar rats weighting ±380g were randomly divided into two groups: 1) sham control (SC) and 2) low-intensity ultrasound therapy (LIUST). For 10 days, after sedation with 3% vaporized halothane, the animals underwent LIUST (I SATA =3MHz, 1 Wcm-2, pulsed mode 2:8ms, 30% cycles for 3 minutes) in the infra-abdominal and inguinal regions. Weight measurements, naso-anal length and metabolic parameters (food and water intake and excretion) were monitored during the study. At the end of the treatment, blood samples were collected for biochemical analyses. Retroperitoneal (RET), perirenal (PR), epididymal (EP) and inguinal (ING) adiposity was evaluated. HOMA-IR (homeostasis model assessment) was calculated to estimate insulin resistance. For statistical analyses, the Student t test, ANOVA and the Tukey test were used, and differences were established as p<0.05. RESULTS: Regarding body weight, the SC group (384±9g) did not show any changes, while the treated group (337±2g) showed reductions (p<0.01). This was also seen in relation to food intake: (25±1g) vs. (21±1g). There were also reductions (p<0.05) in the RET, PR and ING fat-pads, obesity index, triglyceride levels and plasma lipoprotein levels. Hyperinsulinemia without changes in glycemia characterized a state of insulin resistance, which was confirmed by HOMA-IR. CONCLUSIONS: DLC reduced the food intake and body weight and modified the fat deposition in the RET, PR and ING stores in rats. This changed the lipid profile to produce a significant state of insulin resistance.
ultrasound therapy; dermosonic lipoclasis; adipose tissue; energy metabolism; insulin resistance