Gsdma3 is required for mammary gland development in mice

Depletion of Gsdma1/2/3 alleviates PMA-induced epidermal hyperplasia by inhibiting the EGFR-Stat3/Akt pathway

Homeostasis of the skin barrier is essential for maintaining normal skin function. Gasdermin A (GSDMA) is highly expressed in the skin and associated with many skin diseases, such as melanoma and psoriasis. In mice, GSDMA is encoded by three gene homologues, namely Gsdma1, Gsdma2, and Gsdma3. Although Gsdma3 gain-of-function mutations cause hair loss and skin inflammation, Gsdma3-deficient mice do not show any visible phenotypes in skin and hair structures. To explore the physiological function of GSDMA, we generated conventional Gsdma1/2/3 knockout (KO) mice. These mice showed significantly alleviated epidermal hyperplasia and inflammation induced by phorbol 12-myristate 13-acetate (PMA). Furthermore, the alleviation of epidermal hyperplasia depended on the expression of Gsdma1/2/3 specifically in keratinocytes. Mechanistically, Gsdma1/2/3 depletion downregulated epidermal growth factor receptor (EGFR) ligands, leading to the decreased EGFR-Stat3/Akt signalling. These results demonstrate that depletion of Gsdma1/2/3 alleviates PMA-induced epidermal hyperplasia partially by inhibiting the EGFR-Stat3/Akt pathway.

Role of pyroptosis in the pathogenesis of various neurological diseases

Pyroptosis, an inflammatory programmed cell death process, has recently garnered significant attention due to its pivotal role in various neurological diseases. This review delves into the intricate molecular signaling pathways governing pyroptosis, encompassing both caspase-1 dependent and caspase-1 independent routes, while emphasizing the critical role played by the inflammasome machinery in initiating cell death. Notably, we explore the Nucleotide-binding domain leucine-rich repeat (NLR) containing protein family, the Absent in melanoma 2-like receptor family, and the Pyrin receptor family as essential activators of pyroptosis. Additionally, we comprehensively examine the Gasdermin family, renowned for their role as executioner proteins in pyroptosis. Central to our review is the interplay between pyroptosis and various central nervous system (CNS) cell types, including astrocytes, microglia, neurons, and the blood-brain barrier (BBB). Pyroptosis emerges as a significant factor in the pathophysiology of each cell type, highlighting its far-reaching impact on neurological diseases. This review also thoroughly addresses the involvement of pyroptosis in specific neurological conditions, such as HIV infection, drug abuse-mediated pathologies, Alzheimer's disease, and Parkinson's disease. These discussions illuminate the intricate connections between pyroptosis, chronic inflammation, and cell death in the development of these disorders. We also conducted a comparative analysis, contrasting pyroptosis with other cell death mechanisms, thereby shedding light on their unique aspects. This approach helps clarify the distinct contributions of pyroptosis to neuroinflammatory processes. In conclusion, this review offers a comprehensive exploration of the role of pyroptosis in various neurological diseases, emphasizing its multifaceted molecular mechanisms within various CNS cell types. By elucidating the link between pyroptosis and chronic inflammation in the context of neurodegenerative disorders and infections, it provides valuable insights into potential therapeutic targets for mitigating these conditions.

Cancer invasion and metastasis: Insights from murine pubertal mammary gland morphogenesis

Cancer invasion and metastasis accounts for the majority of cancer related mortality. A better understanding of the players that drive the aberrant invasion and migration of tumors cells will provide critical targets to inhibit metastasis. Postnatal pubertal mammary gland morphogenesis is characterized by highly proliferative, invasive, and migratory normal epithelial cells. Identifying the molecular regulators of pubertal gland development is a promising strategy since tumorigenesis and metastasis is postulated to be a consequence of aberrant reactivation of developmental stages. In this review, we summarize the pubertal morphogenesis regulators that are involved in cancer metastasis and revisit pubertal mammary gland transcriptome profiling to uncover both known and unknown metastasis genes. Our updated list of pubertal morphogenesis regulators shows that most are implicated in invasion and metastasis. This review highlights molecular linkages between development and metastasis and provides a guide for exploring novel metastatic drivers.

Pyroptosis, and its Role in Central Nervous System Disease

Pyroptosis is an inflammatory form of cell death executed by transmembrane pore-forming proteins known as gasdermins and can be activated in an inflammasome-dependent or -independent manner. Inflammasome-dependent pyroptosis is triggered in response to pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs) and has emerged as an important player in the pathogenesis of multiple inflammatory diseases, mainly by releasing inflammatory contents. More recently, numerous studies have revealed the intricate mechanisms of pyroptosis and its role in the development of neuroinflammation in central nervous system (CNS) diseases. In this review, we summarize current understandings of the molecular and regulatory mechanisms of pyroptosis. In addition, we discuss how pyroptosis can drive different forms of neurological diseases and new promising therapeutic strategies targeting pyroptosis that can be leveraged to treat neuroinflammation.

Gasdermin family proteins as a permeabilization factor of cell membrane in pyroptosis process

The type of cell death, i.e. apoptosis, autophagy, necrosis or pyroptosis, depends on the inducing factor and the phase of the cell cycle. The main role in immunological response to microorganisms is played by a process called pyroptosis. Pyroptosis induces various types of inflammatory factors in response to molecular patterns associated with pathogens, e.g., bacterial lipopolysaccharide in the canonical or non-canonical pathway depending on the type of caspases involved. In pyroptosis, the gasdermin D protein belonging to the gasdermin protein family (A, B, C, D, E and DFNB59) plays an important role, which is characterized by specific tissue gene expression mainly in epithelial cells, skin and the digestive system and is responsible for regulating the proliferation and differentiation of cells and is responsible for inhibiting or developing cancers in various organs. The GSDM family is responsible for the formation of pores in the cell membrane, enabling the secretion of proinflammatory cytokines (IL-1β and IL-18) involved in initiating inflammatory response pathways by recruiting and activating immune cells at the site of infection. The gasdermin D protein plays an essential role in the non-canonical pyroptosis process, whose N-terminal forming pores in the cell membrane leads to edema, osmotic lysis and, consequently, to the death of the infected cell.

Research progresses of molecular mechanism of pyroptosis and its related diseases

Pyroptosis is a newly discovered untypical form of programmed cell death by inflammatory response, which is dependent on the classic pathway of Caspase-1 and the non-canonical pathway of Caspase-11 in mice or orthologue Caspase-4/-5 in Humans. It has been found that the Gasdermin family of protein is a key molecule in the formation of membrane pores of pyroptosis. After being cleaved by inflammatory caspases, it releases a N-terminal fragment with perforating activity to trigger pyroptosis. That pyroptosis is closely related to the occurrence and development of certain diseases. Now, the molecular mechanism of pyroptosis and pyroptosis-related diseases are reviewed.

Mechanisms of Gasdermin Family Members in Inflammasome Signaling and Cell Death

The Gasdermin (GSDM) family consists of Gasdermin A (GSDMA), Gasdermin B (GSDMB), Gasdermin C (GSDMC), Gasdermin D (GSDMD), Gasdermin E (GSDME) and Pejvakin (PJVK). GSDMD is activated by inflammasome-associated inflammatory caspases. Cleavage of GSDMD by human or mouse caspase-1, human caspase-4, human caspase-5, and mouse caspase-11 liberates the N-terminal effector domain from the C-terminal inhibitory domain. The N-terminal domain oligomerizes in the cell membrane and forms a pore of 10-16 nm in diameter, through which substrates of a smaller diameter, such as interleukin-1β and interleukin-18, are secreted. The increasing abundance of membrane pores ultimately leads to membrane rupture and pyroptosis, releasing the entire cellular content. Other than GSDMD, the N-terminal domain of all GSDMs, with the exception of PJVK, have the ability to form pores. There is evidence to suggest that GSDMB and GSDME are cleaved by apoptotic caspases. Here, we review the mechanistic functions of GSDM proteins with respect to their expression and signaling profile in the cell, with more focused discussions on inflammasome activation and cell death.

Inflammatory caspase-related pyroptosis: mechanism, regulation and therapeutic potential for inflammatory bowel disease

As an essential part of programmed cell death, pyroptosis is an inflammatory response that is elicited upon infection by intracellular pathogens. Metabolic diseases, atherosclerosis and vital organ damage occur if pyroptosis is over-activated. Macrophages are the main cells that induce pyroptosis with the help of intracellular pattern-recognition receptors stimulated by danger signals and pathogenic microorganisms in the cytosol of host cells. Activated inflammatory caspases induce pyroptosis and produce pro-inflammatory cytokines, such as interleukin-1β and interleukin-18. Inflammatory programmed cell death is classified as canonical or non-canonical based on inflammatory caspases, which includes caspase-1 (in human and mouse) and caspase-11 (in mouse) or caspase-4 and -5 (in humans). Activated inflammatory caspases cleave the pore-forming effector protein, gasdermin-D, inducing osmotic pressure deregulation of internal fluids and subsequently rupturing the cell membranes. Inflammatory caspases could be attractive therapeutic targets for inflammatory bowel disease (IBD) in which pyroptosis may play an important role. This article reviews the current understanding of the mechanism of pyroptosis, focusing on the regulation of inflammatory caspases and therapeutic strategies for IBD.