Figure 1.
Reduced body weight and body fat mass in synaptotagmin-7 KO mice.
(A) Body weights of synaptotagmin-7 KO (Syt7-/-) and control (Ctrl.) mice at 5, 14, and 24 weeks of age. N = 8–32 per group. (B, C) Fat mass (B) and proportion of body fat (C) in synaptotagmin-7 KO and control mice at 24 weeks of age. (D, E) Lean mass (D) and proportion of body lean (E) in synaptotagmin-7 KO and control mice at 24 weeks of age. All data are expressed as means ± SEM. N = 24–32 per group. *, P<0.05; **, P<0.01.
Figure 2.
Enhanced metabolism in synaptotagmin-7 KO mice.
(A) Rate of daily oxygen consumption for synaptotagmin-7 KO (Syt7-/-) and control (Ctrl.) mice during the day, night and whole-day periods. (B) Basal metabolic rate as measured in terms of oxygen consumption (ml/hour/kg lean mass) for synaptotagmin-7 KO and control mice. (C) RER of synaptotagmin-7 KO and control mice over a 24-hour monitoring period. (D) RER calculated from data in (C) during day (0700–1900 h) and night (1900–0700 h). All data are presented as means ± SEM. N = 9–10 per genotype. *, P<0.05; **, P<0.01.
Figure 3.
Enhanced lipolytic enzyme and reduced muscle TG content in synaptotagmin-7 KO mice.
(A, B) Representative immunoblots and quantification of protein levels of phopho-HSL (pHSL) from fat pads (A), and CPT1 from skeletal muscle mitochondria (B) of 20–24 week old synaptotagmin-7 KO and littermate control mice. Densitometric quantification for each protein was normalized against beta-tubulin from 3-5 independent pairs of synaptotagmin-7 KO and control mouse samples. (C) Triglyceride (TG) and (D) glycerol content from muscle samples. N = 4 per genotype. Data are presented as means ± SEM. *, P<0.05; **, P<0.01.
Table 1.
Plasma or serum analytes of synaptotagmin-7 KO and control mice.
Figure 4.
Increased UCP3 expression in the skeletal muscle mitochondria of synaptotagmin-7 KO mice.
(A, B) Representative immunoblots of UCP1 from brown adipose tissue (A) and UCP3 from skeletal muscle (B) of 20–24 week old synaptotagmin-7 KO and control mice. Relative densitometric quantification was normalized against beta-tubulin. Each set of samples was from 3–5 mice. (C) Synaptotagmin-7 (arrows) was not detected in skeletal muscle. Data are presented as means ± SEM. **, P<0.01.