Found 3 results
Open Access
Review
22 May 2025NLRP3 Inflammasome and IL-11 in Systemic Sclerosis Pulmonary Fibroblasts
Systemic sclerosis (SSc) is an autoimmune disease characterized by widespread fibrosis affecting multiple organ systems. There is clinical heterogeneity among patients with SSc in terms of the organs affected. However, the pathophysiology of the disease remains elusive. The NLRP3 inflammasome is upregulated in SSc and exerts its fibrotic effects through activation of caspase-1, which in turn activates a fibrotic signaling cascade, resulting in increased collagen deposition and myofibroblast transition. Recently, IL-11 has been shown to be elevated in disease and has been shown to participate in downstream signaling via the NLRP3 inflammasome. A significant number of patients with SSc will develop pulmonary involvement, termed interstitial lung disease (SSc-ILD). Though this type of pulmonary involvement is distinct from other types of pulmonary fibrosis (such as idiopathic pulmonary fibrosis), it may be a valuable model to study mechanisms of fibrosis that could apply to other fibrotic diseases. Here, we discuss recent advances in understanding the mechanisms of the NLRP3 inflammasome and IL-11 in SSc pulmonary fibroblasts. We tie together some of the recent findings, such as senescence, the unfolded protein response, and reactive oxygen species, that contribute to fibrotic pathology via modulating NLRP3 activation, possibly leading to IL-11 expression.
Open Access
Review
26 February 2024Mechanisms of Fibroblast Activation during Fibrotic Tissue Remodeling
Fibrosis can occur in almost every organ system. It can occur in single organs, such as in idiopathic pulmonary fibrosis (IPF), or affect multiple organs as in systemic sclerosis (SSc). Fibrotic diseases are recognized as major cause of morbidity and mortality in modern societies due to the dysfunction or loss of function of the affected organs. This dysfunction is caused by progressive deposition of extracellular matrix proteins released by activated fibroblasts. Activation of fibroblasts and differentiation into myofibroblasts is required for physiological tissue remodeling, e.g, during wound healing. Disruption of regulatory mechanisms, however, results in chronic and uncontrolled activity of fibroblasts and myofibroblasts. Intensive research during the past years identified several core pathways of pathophysiological relevance, and described different fibroblast subsets based on their expression profile in fibrotic tissue. Herein, we discuss the molecular changes in fibroblasts leading to persistent activation during fibrotic tissue remodeling with a focus on lung fibrosis and SSc.
Open Access
Review
21 December 2023TANGO1 Dances to Export of Procollagen from the Endoplasmic Reticulum
The endoplasmic reticulum (ER) to Golgi secretory pathway is an elegantly complex process whereby protein cargoes are manufactured, folded, and distributed from the ER to the cisternal layers of the Golgi stack before they are delivered to their final destinations. The export of large bulky cargoes such as procollagen and its trafficking to the Golgi is a sophisticated mechanism requiring TANGO1 (Transport ANd Golgi Organization protein 1. It is also called MIA3 (Melanoma Inhibitory Activity protein 3). TANGO1 has two prominent isoforms, TANGO1-Long and TANGO1-Short, and each isoform has specific functions. On the luminal side, TANGO1-Long has an HSP47 recruitment domain and uses this protein to collect collagen. It can also tether its paralog isoforms cTAGE5 and TALI and along with these proteins enlarges the vesicle to accommodate procollagen. Recent studies show that TANGO1-Long combines retrograde membrane flow with anterograde cargo transport. This complex mechanism is highly activated in fibrosis and promotes the excessive deposition of collagen in the tissues. The therapeutic targeting of TANGO1 may prove successful in the control of fibrotic disorders. This review focuses on TANGO1 and its complex interaction with other procollagen export factors that modulate increased vesicle size to accommodate the export of procollagen.
