l carnitine and weight loss pubmed The bright the dark sides of L-carnitine supplementation: a systematic review | Journal of the International Society of Sports Nutrition Role of carnitine in disease

Yes, you can take them together

Different mechanisms have been proposed in different cellular, organ, and animal models, including transcellular and paracellular routes

This transporter localizes to the trans-Golgi network or late endosomes under basal conditions, but it relocalizes in a copper-dependent manner to a subapical, vesicular compartment, which facilitates both copper incorporation into ceruloplasmin and biliary copper excretion via lysosomes.180 Apart from copper, Long-Evans Cinnamon rats also have abnormal hepatic accumulation of iron.181 Chronic copper/iron accumulation in these rats leads to a 50% increase in lipid peroxidation, presumably due to copper/iron capability to induce oxidative stress by generating ROS via both mitochondrial dysfunction182 and Fenton-type, copper/iron-catalyzed Haber-Weiss reaction.183,184 These mutant rats exhibit a reduced basal bile salt-biliary excretion compared with normal, Long-Evans Agouti rats

doi: 10.1089/cbr.2012.1443 162 DattaKSumanSFornaceAJ

Adding retatrutide changes the metabolic environment significantly