Microbial anti-inflammatory molecule (MAM) (MAM)

The Microbial anti-inflammatory molecule (MAM) is a 15 kDa protein produced by the commensal gut bacterium Faecalibacterium prausnitzii, which is one of the most abundant species in the healthy human microbiota [2, 6, 15]. MAM serves as a key effector molecule that mediates the anti-inflammatory effects of the bacterium, primarily by inhibiting the NF-kappaB signaling pathway in intestinal epithelial cells [1, 2, 3, 15]. This inhibition leads to a significant reduction in the production of pro-inflammatory cytokines, such as Interleukin-8 (IL-8), and helps to suppress Th1, Th2, and Th17 immune responses [4, 6, 11]. Furthermore, MAM plays a crucial role in maintaining and restoring the intestinal barrier by upregulating tight junction proteins like Zonula occludens-1 (ZO-1), which prevents the translocation of pathogens and toxins [1]. In clinical contexts, a depletion of Faecalibacterium prausnitzii and its associated MAM protein is a hallmark of dysbiosis in patients with Crohn's disease, ulcerative colitis, and other inflammatory bowel diseases (IBD) [2, 5, 6, 11]. Research has also linked MAM deficiency to metabolic disorders such as type 2 diabetes and potentially neurodegenerative conditions like Parkinson's disease [1, 15]. Therapeutic strategies currently under investigation include the administration of recombinant MAM protein, MAM-derived peptides, or engineered "live biotherapeutic" probiotics, such as Lactococcus lactis, designed to deliver the MAM gene directly to the intestinal mucosa [2, 3, 4, 6]. These approaches aim to restore gut homeostasis and alleviate chronic inflammation by mimicking the natural protective mechanisms of the commensal microbiota [5, 15].

Other names

MAM proteinFaecalibacterium prausnitzii anti-inflammatory proteinFaecalibacterium duncaniae anti-inflammatory proteinMicrobial anti-inflammatory molecule 1

Inhibition of the NF-kappaB signaling pathway and upregulation of tight junction proteins (e.g., ZO-1) to restore intestinal barrier integrity and reduce pro-inflammatory cytokine secretion [1, 2, 3, 6, 15].