A 12-year-old boy with BMI at the 98th percentile presents with dark velvety pigmentation over the neck and axilla. Fasting insulin levels are elevated. What is the underlying pathophysiological mechanism responsible for this skin finding?
A
Autoimmune destruction of melanocytes
B
Hyperinsulinemia stimulating keratinocyte and dermal fibroblast proliferation
C
Excess melanin deposition due to UV exposure
D
Increased cortisol causing skin thickening