TRPV1-null mice are protected from diet-induced obesity
Arianne L Motter1, Gerard P Ahern
1Department of Pharmacology, Georgetown University, 3900 Reservoir Road NW, Washington, DC 20007, USA.
Abstract:
We explored a role for the capsaicin receptor, transient receptor potential channel vanilloid type 1 (TRPV1), in the regulation of feeding and body mass. On a 4.5% fat diet, wild-type and TRPV1-null mice gained equivalent body mass. On an 11% fat diet, however, TRPV1-null mice gained significantly less mass and adiposity; at 44 weeks the mean body weights of wild-type and TRPV1-null mice were approximately 51 and 34g, respectively. Both groups of mice consumed equivalent energy and absorbed similar amounts of lipids. TRPV1-null mice, however, exhibited a significantly greater thermogenic capacity. Interestingly, we found that 3T3-L1 preadipocytes expressed functional calcitonin gene-related peptide receptors. Thus, these data support a potential neurogenic mechanism by which TRPV1-sensitive sensory nerves may regulate energy and fat metabolism.
Insights
The capsaicin receptor, transient receptor potential channel vanilloid type 1 (TRPV1), plays a role in regulating body mass. TRPV1-null mice showed reduced weight gain and adiposity, suggesting a neurogenic mechanism for energy metabolism.
Area of Science:
- Physiology
- Metabolism
- Neuroscience
Background:
- The capsaicin receptor, transient receptor potential channel vanilloid type 1 (TRPV1), is involved in sensory perception.
- Its role in regulating feeding behavior and body mass is not fully understood.
Purpose of the Study:
- To investigate the function of TRPV1 in the regulation of energy balance and body mass.
- To explore the potential neurogenic mechanisms underlying TRPV1's influence on metabolism.
Main Methods:
- Comparison of body mass gain and adiposity between wild-type and TRPV1-null mice on different fat diets.
- Assessment of energy intake, lipid absorption, and thermogenic capacity.
- Analysis of calcitonin gene-related peptide receptor expression in preadipocytes.
Main Results:
- TRPV1-null mice exhibited significantly less mass gain and adiposity on an 11% fat diet compared to wild-type mice.
- Energy intake and lipid absorption were similar between groups.
- TRPV1-null mice demonstrated a greater thermogenic capacity.
- Functional calcitonin gene-related peptide receptors were detected in 3T3-L1 preadipocytes.
Conclusions:
- TRPV1 signaling is implicated in the regulation of body mass and fat metabolism.
- TRPV1-sensitive sensory nerves may contribute to energy homeostasis through a neurogenic mechanism.
- These findings suggest TRPV1 as a potential target for metabolic interventions.
