LEP and obesity due to melanocortin 4 receptor deficiency: However, despite a lack of data, there is increasing indirect evidence for modulation of cardiac ion channel function by distinct obesity-associated factors including dyslipidemia (Aromolaran et al., 2016), leptin (Lin et al., 2013), hyperglycemia (Zhang et al., 2006), and pro-inflammatory cytokines (Zhao et al., 2016).