Given that LepR-Cre Slc7a5fl/fl mice showed impaired sympathetic tone and leptin insensitivity in LepR-expressing VMH neurons prior to the onset of obesity (Figure 5), we reasoned that LAT1 in LepR-expressing neurons may play an important role in regulating bone homeostasis in addition to energy homeostasis. This evidence concerns the gene SLC7A5 and obesity due to melanocortin 4 receptor deficiency.