MMP3 and obesity due to melanocortin 4 receptor deficiency: However, significant adipose tissue hypertrophy and increased adipose tissue angiogenesis was observed only in GWAT of MMP3−/− mice but not in ScWAT, suggesting a preventive role of MMP3 from excessive visceral adipose tissue expansion in nutritionally induced obesity in male animals and that ScWAT probably expands through hyperplasia in the absence of MMP3 [57].