Intestinal microbiota metabolism of l carnitine, a nutrient in red meat, promotes atherosclerosis Nature Medicine Frontiers Analgesic and Antidepressant Effects of the Clinical Glutamate Modulators Acetyl L Carnitine and Ketamine PDF) Acetyl L Carnitine protects against LPS induced depression via PPAR induced inhibition of NF B NLRP3 pathway Characterization of TMAO productivity from carnitine challenge facilitates personalized nutrition and microbiome signatures discovery Microbiome Springer Nature Link