Language
Country/Area
No result found
The Miracle of the AIM Protein: Why Is It So Critical in Autoimmune Diseases?
In today's medical research, pickle protein (AIM) has gradually received widespread attention. This protein produced by macrophages not only regulates immune responses but also plays an important role in a variety of intracellular processes, including lipid metabolism and apoptosis. This article will explore the importance of the AIM protein in autoimmune diseases, highlighting its potential role as one of the key molecules.
Overview
AIM is a 40 kDa protein encoded by the CD5L gene. It is primarily produced by tissue-resident macrophages and is transcriptionally activated through activated nuclear receptors (LXR/RXR) and/or the transcription factor MAFB. AIM belongs to the scavenger receptor cysteine-rich (SRCR) superfamily and possesses three SRCR domains. In serum, AIM binds to IgM pentamers, preventing renal excretion and maintaining high levels of circulation. Although AIM bound to IgM is in an inactive state, it dissociates during disease and exerts its function of promoting lesion repair.
Some results show that AIM expression patterns vary in different organisms, and a 2019 study found that dogs have a broader AIM expression pattern than humans and mice.
AIM functions
AIM has multiple roles in the body, and its diverse functions include regulating intracellular processes such as lipid metabolism and apoptosis, inhibiting cholesterol synthesis, and affecting the pathogenicity of Th17 cells. Despite its diverse effects in the regulation of inflammation, the specific mechanisms by which it plays a role in attracting or promoting inflammation remain unclear. The specific receptor for AIM has not yet been identified, but it is capable of binding to molecules such as CD36, a membrane glycoprotein that plays a role in a variety of cellular functions, including inflammation and atherosclerosis.
Early studies have shown that AIM is increased in autoimmune diseases, and the potential of AIM as a sensitive biomarker is gradually being recognized. 』
Role in autoimmune diseases
In autoimmune diseases, the increased expression of AIM makes it a potential biomarker, but its specific role and mechanism remain unclear. In patients with ALS, progressive multiple sclerosis, rheumatoid arthritis, and osteoarthritis, AIM levels are significantly higher than normal. In patients with knee OA, AIM in CD14+ macrophages may play a potential role in promoting the survival of synovial macrophages and promoting arthritis. In lupus erythematosus, AIM concentrations correlate with disease activity and inflammatory markers and decrease with effective treatment.
The role of cardiopulmonary disease
The role of AIM in cardiovascular and pulmonary diseases mainly focuses on inflammation, inhibiting macrophage apoptosis, and enhancing inflammatory responses. In cardiovascular diseases, AIM exacerbates metabolic disorders and atherosclerosis, which may lead to diabetes and cardiovascular events. AIM is highly expressed in foam macrophages in atherosclerotic plaques, promoting macrophage survival and inflammatory response, and AIM-deficient mice have significantly improved outcomes after myocardial infarction, with increased survival rates and reduced rates of cardiac rupture. .
Dual role in liver inflammatory injury
AIM plays a dual role in liver dynamics. In lipid metabolism, it catalyzes inflammation associated with lipolysis, while in the liver microenvironment, it antagonizes the profibrotic effects of TGFβ1. This adaptive response of AIM aims to reduce inflammatory signaling and fibrosis. In liver injury models, the protective effect of AIM against fibrosis has also gradually been shown. At the same time, the high expression of AIM in hepatocellular carcinoma (HCC) is related to cancer cell proliferation and resistance to apoptosis.
Dual role in renal function
In serum, AIM derived from IgM pentamers plays multiple roles, including a role in acute kidney injury (AKI). A 2016 study showed that increases in AIM during AKI help promote kidney repair. Increased AIM combines with kidney injury molecules (KIM) to promote the removal of renal cell residues and assist tissue repair. AKI studies in AIM-deficient mice have shown that AIM deficiency reduces the ability to clear cellular debris and increases mortality.
Exploring the role of AIM in various diseases may reveal new treatment paths and insights for us.
