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Dermal filler complications and management
Published in Michael Parker, Charlie James, Fundamentals for Cosmetic Practice, 2022
Phagocytes are a family of cells comprised of macrophages and neutrophils which engulf and digest microbes and cellular debris. By digesting unwanted bacteria and debris, the surrounding environment can be cleansed to allow for the eradication of infection and proper wound healing. Infections cause the release of cytokines which attract phagocytes to the affected area. As they migrate, macrophages differentiate and change their behaviour, some become wandering macrophages that become larger and begin to hunt down pathogens and toxic debris, whereas other macrophages will become fixed macrophages and stand guard within specific tissues to anticipate any potential spread of infection. Alongside their direct role in removing harmful pathogens and material from an area of infection, macrophages also play a key role in mediating inflammation and wound healing, as discussed previously.
Comparative Anatomy, Physiology, and Biochemistry of Mammalian Skin
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
Another type of cell found in connective tissue is the macrophage. It is known by a variety of names such as clasmatocyte and histiocyte. The macrophage has been postulated to be derived from the monocyte. The life span may be 2 to 3 months, depending on the tissue. Macrophages can be identified by vital staining, an excellent method demonstrating macrophages “in action”. Ultrastructurally, macrophages have an irregular shape. Their cell membrane has been modified into finger-like projections or pseudopods. The nucleus is indented and common organelles such as mitochondria and a small amount of rough endoplasmic reticulum are present. Macrophages contain numerous types of lysosomes with pinocytotic and phagocytotic vacuoles. The function of macrophages is to engulf and destroy bacteria or foreign substances, and to process antigens for presentation to the immune system. The functional activity of a macrophage can be appreciated by the complexity of its membrane modifications.38,202,204
Endotoxin and Cancer
Published in Helmut Brade, Steven M. Opal, Stefanie N. Vogel, David C. Morrison, Endotoxin in Health and Disease, 2020
Minghuang Zhang, Kevin J. Tracey
The concept that macrophages play a role in host defense against foreign intruders was first elaborated by Metchnikoff (50). It has subsequently become clear that macrophages play an essential role in regulating immune and inflammatory responses through phagocytosis, antigen presentation, and cytokine secretion. Mono-nuclear cell infiltration is a common histological observation in cancers, and clinically the presence of mononuclear cell infiltrates is associated with a better prognosis as compared to similar tumor types lacking infiltrates (51,52). Experimental studies have demonstrated that activation of tumor-infiltrating macrophages can modulate tumor regression (53,54).
Deer antler based active ingredients have protective effects on LPS/d -GalN-induced acute liver injury in mice through MAPK and NF-κB signalling pathways
Published in Pharmaceutical Biology, 2022
Guixiang He, Quanmin Zhao, Yan Zhao, Ying Zong, Shigang Gu, Mengjie Li, Renjie Li, Jiaxin Sun
Macrophages are the most important immune cells and play a variety of immunomodulatory roles in various inflammatory diseases. Once activated, macrophages release a series of inflammatory cytokines (Fujiwara and Kobayashi 2005). Lipopolysaccharide is a cell wall component of Gram-negative bacteria, which interferes with the receptors of immune cells (Chen et al. 2018). Lipopolysaccharide is one of the most potent activators of mononuclear macrophages and is known to produce pro-inflammatory cytokines such as IL-1β, IL-6 and TNF-α and pro-inflammatory mediators, such as NO and PGE2 (Yang et al. 2012; Abarikwu 2014). Therefore, we selected mouse monocyte macrophages RAW 264.7 to screen the isolated and purified antler base protein extract, and found that the NO production of RAW264.7 cells after 4 h pre-treatment with R1 protein component was significantly reduced. We also measured the cytokines IL-6, IL-1β and TNF-α to further verify the anti-inflammatory effect of the R1 protein component. The results demonstrated that pre-treatment with R1 protein component, inflammatory factors were reduced in a dose-dependent manner. Therefore, we speculate that the R1 protein component of deer antler base may have a pre-protective effect on ALI through anti-inflammatory effects.
β-Hydroxyisovalerylshikonin regulates macrophage polarization via the AMPK/Nrf2 pathway and ameliorates sepsis in mice
Published in Pharmaceutical Biology, 2022
Tao Pan, Yabin Chang, Min He, Zehui He, Jun Jiang, Xinling Ren, Fang Zhang
This study demonstrated for the first time that β-HIVS suppressed macrophage M1 polarization and promoted M2 polarization via activation of the AMPK/Nrf2 pathway. Macrophage is an attractive therapeutic target. The important role of macrophage polarization in the development of diseases has attracted considerable attention in recent years. Previous studies have shown that macrophage polarization is closely linked to autoimmune diseases, rheumatoid arthritis, and obesity (Wynn et al. 2013; Ma et al. 2019), and play a vital role in the progression of sepsis (Fu et al. 2020). The results of this study imply that β-HIVS may have therapeutic potential for the treatment of these diseases, especially sepsis, and its non‑cytotoxic dose is highly favourable to applied to clinical practice.
Scavenger Receptor A1 Signaling Pathways Affecting Macrophage Functions in Innate and Adaptive Immunity
Published in Immunological Investigations, 2022
Elizabeth Linares-Alcántara, Fela Mendlovic
Macrophages are highly heterogeneous and may be differentially activated, i.e., M1 or classically activated and M2 or alternatively activated depending on their microenvironment (Stout et al. 2005). These two phenotypes are involved in different stages of the immune response and express diverse cytokines, chemokines, and surface receptors. The M1 macrophages differentiate in the presence of INF-γ and IL-12, are characterized by the production of proinflammatory cytokines IL-1β, IL-6, TNF-α, express iNOS, and are mainly involved in anti-microbial and anti-tumor activity. On the other hand, M2 macrophages respond to IL-4, IL-10, IL-13 and glucocorticoids and produce IL-10, Arginase I (Arg-1) that competes with iNOS, as well as galectin-3 (Gal-3), mannose receptor, chitinase-like lectin (YM1) and resistin-like secreted protein (FIZZ1). M2 macrophages are involved in the anti-helminth responses, resolution of inflammation and tissue remodeling (Sica and Mantovani 2012). The balance in macrophage activation is essential for a coordinated immune response. Both macrophage phenotypes have been implicated in disease and homeostasis.