Background: To date no attempts have been made to determine the role of the endothelial cell derived product, endothelin-1 (ET-1) in granulation tissue development. This study investigates the cellular immunolocalization of ET-1 and its pharmacologic effect on myofibroblast-mediated rat croton oil-induced granulation tissue contraction.
Experimental Design: The distribution, cellular localization and temporal production of ET-1 in the tissues was determined by immunohistochemistry at days 7, 14, 21, and 28. The contractile response of the granulation tissue to ET-1 was tested over the same time period, and it effects modified by use of calcium antagonists. The pharmacologic profile was correlated to the ultrastructural development of contractile fibroblast-like cells within the tissue.
Results: Endothelin-1 caused reversible concentration-dependent contraction of the granulation tissue. The 21-day granulation tissue was the most responsive, with a maximum increase in tension of 458.9 +/- 41.1 mg; this response could be inhibited by use of calcium antagonists. Of the calcium antagonists tested, verapamil (1 x 10(-4) M) was the most potent inhibitor, giving a 43% reduction in maximum amplitude of the response. It is suggested that entry of extracellular calcium via the L-type potential operated calcium channel, is involved in ET-1 induced responses in contractile fibroblast-like cells or myofibroblasts. Ultrastructural analysis showed a correlation between the pharmacologic sensitivity of the tissue and the development of contractile fibroblast-like cells. The number of cells expressing the phenotypic characteristics of a myofibroblast increased with time, and were first observed at day 7. Immunohistochemistry revealed the presence of increasing numbers of ET-1 labeled cells throughout the time course of study. The ET-1 positive cells were localized to the capillaries. Immunolabeling of serial sections with the rodent endothelial cell specific lectin, Bandeiraea simplicifolia isolectin B4 and factor VIII-related antigen, confirmed the specific localization of ET-1 to endothelial cells.
Conclusions: We present evidence that ET-1 may be an endogenous modulator of myofibroblast-mediated granulation tissue contraction and that the use of calcium antagonists could afford a possible therapeutic control in the treatment of fibrocontractive diseases.
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J Nanobiotechnology
January 2025
Department of Burns, Wound Repair and Reconstruction, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, 510080, China.
Hypertrophic scar (HS) is a common fibroproliferative disorders with no fully effective treatments. The conversion of fibroblasts to myofibroblasts is known to play a critical role in HS formation, making it essential to identify molecules that promote myofibroblast dedifferentiation and to elucidate their underlying mechanisms. In this study, we used comparative transcriptomics and single-cell sequencing to identify key molecules and pathways that mediate fibrosis and myofibroblast transdifferentiation.
View Article and Find Full Text PDFBiomed Pharmacother
January 2025
Department of Surgery, Division of Urology, London Health Sciences Center, Western University, London, Ontario, Canada; Matthew Mailing Center for Translational Transplant Studies, London Health Sciences Center, Western University, London, Ontario, Canada; Multi-Organ Transplant Program, London Health Sciences Center, Western University, London, Ontario, Canada; Department of Microbiology & Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada. Electronic address:
Frostbite injury refers to cold tissue injury which typically affects the peripheral areas of the body, and is associated with limb loss and high rates of morbidity. Historically, treatment options have been limited to supportive care, leading to suboptimal outcomes for affected patients. The pathophysiology of frostbite injury has been understood in recent years to share similarity with that of cold ischemia-reperfusion injury as seen in solid organ transplantation, of which mitochondria play an important contributing role.
View Article and Find Full Text PDFCureus
December 2024
Colorectal Surgery, Blackpool Teaching Hospitals, Blackpool, GBR.
Meckel's diverticulum (MD) is a common congenital anomaly of the gastrointestinal tract, present in approximately 2% of the population. While typically asymptomatic, MD can lead to complications such as obstruction and intussusception. Here, we present a case report of a man presenting with abdominal pain with an incidental finding of MD complicated by intussusception and our management approach.
View Article and Find Full Text PDFPlast Reconstr Surg Glob Open
January 2025
From the Department of Plastic Surgery, Hull University Teaching Hospitals, East Riding of Yorkshire, United Kingdom.
Biodegradable temporizing matrix (BTM) is a synthetic biodegradable dermal matrix that helps develop a non-skin graft amenable wound bed (eg, over tendon or bone) into a graftable wound bed, by acting as an inert scaffold for angiogenesis and formation of granulation tissue. There is currently a paucity of evidence to encourage its use in scalp defects following skin malignancy excision. This retrospective analysis aimed to evaluate the utility of BTM in this patient subset.
View Article and Find Full Text PDFIn Vitro Model
June 2024
Department of Pharmacy, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH UK.
Unlabelled: Wound debridement is commonplace in expediting wound healing in the clinic. Despite this, there are limited resources available for simulation training for practitioners prior to facing real-life patients. Typically, citrus peels or porcine skin are employed in a vain attempt to improve debridement proficiency, yet these fail to provide a realistic experience of the textures and consistencies of wounds.
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