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Autopsy & Case Reports 2024Esophageal melanocytosis is a rare entity defined by the proliferation of a melanocytic basal layer of the esophageal squamous lining and deposition of melanin in the...
Esophageal melanocytosis is a rare entity defined by the proliferation of a melanocytic basal layer of the esophageal squamous lining and deposition of melanin in the esophageal mucosa. Esophageal melanocytosis is considered a benign entity of unknown etiology; however, it has been reported as a melanoma precursor. We report a case of esophageal melanocytosis in a diabetic and hypertensive 67-year-old male with recurrent dizziness and syncope for the past 6 months. Given his complaint of dyspepsia, he underwent an upper gastrointestinal endoscopy, in which an esophageal biopsy revealed the diagnosis of esophageal melanocytosis. The definitive diagnosis of esophageal melanocytosis can only be made by histological analysis. The histologic differential diagnoses include melanocytic nevi and malignant melanoma. Therefore, they need to be ruled out.
PubMed: 38803486
DOI: 10.4322/acr.2024.487 -
Frontiers in Cell and Developmental... 2023Melanocytes, which originate from the neuroectoderm, are specialized cells responsible for producing pigments and possessing a dendritic morphology. These cells migrate... (Review)
Review
Melanocytes, which originate from the neuroectoderm, are specialized cells responsible for producing pigments and possessing a dendritic morphology. These cells migrate to the epidermis and follicles, contributing to skin and hair pigmentation during embryonic development. The remarkable self-renewal capacity of melanocytes enables them to effectively restore hair and skin pigmentation. The synthesis of melanin to safeguard the skin against damage caused by ultraviolet radiation, as well as the enigmatic immune function of melanocytes, demonstrate their indispensable contributions to maintaining cutaneous homeostasis. The regulation of cutaneous pigmentation involves an intricate network influenced by intrinsic cellular signals within melanocytes and extracellular cues. Therefore, this paper provides a comprehensive review of the role of melanocytes in skin biology. This in-depth analysis could open novel avenues for research aimed at the prevention and treatment of skin disorders.
PubMed: 38078014
DOI: 10.3389/fcell.2023.1309557 -
Theranostics 2023Senescent melanocytes accumulate in photoaged skin and are closely related to skin aging. A better understanding of the molecular characteristics of senescent...
Senescent melanocytes accumulate in photoaged skin and are closely related to skin aging. A better understanding of the molecular characteristics of senescent melanocytes may be the key to controlling skin aging. We have developed an model of senescence in melanocytes using UV irradiation and investigated the functional characteristics and molecular mechanisms underlying senescence in UV-irradiated melanocytes. We have highlighted that senescent melanocytes are characterized by melanosome transport dysfunction resulting in melanin accumulation. The defective melanosome transport was confirmed with the ultrastructural characterization of both UV-induced senescent melanocytes and melanocytes of hypopigmented aging skin. A single-cell transcriptomic analysis revealed that the glycolytic metabolism pathway appeared to be significantly upregulated in most senescent phenotypes. Furthermore, the inhibition of glycolysis by pharmacological compounds mitigates the pro-aging effects of melanocytes senescence, suggesting that alterations in cellular glucose metabolism act as a driving force for senescence in melanocytes. These results demonstrate that senescent melanocytes are characterized by glycolytic metabolism changes and a defective melanosome transport process, which may be related to impaired mitochondrial function, highlighting the importance of metabolic reprogramming in regulating melanocyte senescence.
Topics: Melanosomes; Melanocytes; Skin; Melanins; Glycolysis; Cellular Senescence
PubMed: 37554281
DOI: 10.7150/thno.84912 -
International Journal of Molecular... Aug 2023Fungal pathogens of the species complex ( SC) are a major cause of fungal meningitis in immunocompromised individuals. As with other melanotic microorganisms associated... (Review)
Review
Fungal pathogens of the species complex ( SC) are a major cause of fungal meningitis in immunocompromised individuals. As with other melanotic microorganisms associated with human diseases, the cell-wall-associated melanin of SC is a major virulence factor that contributes to its ability to evade host immune responses. The levels of melanin substrate and the regulation of melanin formation could be influenced by the microbiota-gut-brain axis. Moreover, recent studies show that infections cause dysbiosis in the human gut microbiome. In this review, we discuss the potential association between cryptococcal meningitis and the gut microbiome. Additionally, the significant potential of targeting the gut microbiome in the diagnosis and treatment of this debilitating disease is emphasized.
Topics: Humans; Meningitis, Cryptococcal; Gastrointestinal Microbiome; Melanins; Brain-Gut Axis; Cryptococcus neoformans; Cryptococcosis
PubMed: 37686320
DOI: 10.3390/ijms241713515