PLOD1 and obesity due to melanocortin 4 receptor deficiency: Importantly, our observation of a positive correlation between endotoxaemia (LBP) and serum LH (r = 0.334, p = 0.019) suggests a peripheral (testicular) cause for obesity related hypogonadism, with a compensatory rise in LH release in response to falling testosterone production, rather than adipose aromatase/estradiol mediated central hypogonadism.