Phytochemicals as modulators of M1-M2 macrophages in inflammation

Abstract

Macrophages are critical mediators of the innate immune response against foreign pathogens, including bacteria, physical stress, and injury. Therefore, these cells play a key role in the “inflammatory pathway” which in turn can lead to an array of diseases and disorders such as autoimmune neuropathies and myocarditis, inflammatory bowel disease, atherosclerosis, sepsis, arthritis, diabetes, and angiogenesis. Recently, more studies have focused on the macrophages inflammatory diseases since the discovery of the two subtypes of macrophages, which are differentiated on the basis of their phenotype and distinct gene expression pattern. Of these, M1 macrophages are pro-inflammatory and responsible for inflammatory signaling, while M2 are anti-inflammatory macrophages that participate in the resolution of the inflammatory process, M2 macrophages produce anti-inflammatory cytokines, thereby contributing to tissue healing. Many studies have shown the role of these two subtypes in the inflammatory pathway, and their emergence appears to decide the fate of inflammatory signaling and disease progression. As a next step in directing the pro-inflammatory response toward the anti-inflammatory type after an insult by a foreign pathogen (e. g., bacterial lipopolysaccharide), investigators have identified many natural compounds that have the potential to modulate M1 to M2 macrophages. In this review, we provide a focused discussion of advances in the identification of natural therapeutic molecules with anti-inflammatory properties that modulate the phenotype of macrophages from M1 to M2.

Transcriptome meta-analysis reveals differences of immune profile between eutopic endometrium from stage I-II and III-IV endometriosis independently of hormonal milieu

“…Our data reinforce the idea that the search for immunomodulators is proving to be promising for the treatment of the endometriosis, despite the fact that there have been no definitive successes to date 96 . New advances in the modulation of the M1-M2 macrophage polarization 97,98 and in targeting NKT cells 99 will provide a foundation for more effective treatment of this disease.…”

Macrophage CCL22 expression in the tumor microenvironment and implications for survival in patients with squamous cell carcinoma of the tongue

“…CCL22 is known to be involved in the migration of Th2 cells and Tregs via CCR4 . When Th2 cells accumulate in the periphery of the tumor, the surrounding tumor microenvironment is dominated by Th2 cytokines, such as IL‐4, thereby promoting the differentiation of TAMs into M2‐like macrophages . An increase in this positive mechanism further increases the number of CD163‐positive TAMs surrounding the tumor and promotes lymphatic vessel invasion …”

“…Th2 cytokines, such as IL-4, 13 thereby promoting the differentiation of TAMs into M2-like macrophages. 28 An increase in this positive mechanism further increases the number of CD163-positive TAMs surrounding the tumor and promotes lymphatic vessel invasion. 10 A correlation between the number of CTLs and prognosis has been reported for several cancers, including OSCC.…”

Particulate matter exposure aggravates osteoarthritis severity

“…Moreover, the polarization ratio of macrophage phenotypes may be affected by PM. In general, macrophages can be separated into M1 (pro-inflammatory role) or M2 phenotypes (anti-inflammatory role) [39,40]. As shown in Figure 3, the total number of macrophages, detected by CD68 signals, was significantly increased in the PM (5 mg) with MIA group.…”