Melatonin is a multifunctional biomolecule with demonstrated stimulatory, inhibitory, and antioxidant effects, including both receptor-mediated and receptor-independent mechanisms of action. One of its more perplexing effects is the disruption of regeneration in planaria. Head regeneration in planaria is a remarkable phenomenon in which stem cells (neoblasts) migrate to the wound site, proliferate, then differentiate into all functional tissue types within days of injury. We investigated how both the timing and duration of melatonin exposure affect head regeneration in the planaria Phagocata gracilis (Haldeman). Our results demonstrate that P. gracilis is capable of recovery from the melatonin-induced delay of regeneration and reveal the time required to recover to control levels. Further, we found evidence of regenerative stage-specific responses to discontinuous melatonin exposure, including non-inhibitory effects. Further exploration of melatonin's effects on regeneration can be targeted to specific regenerative processes, and the possibility of multiple mechanisms of action should be recognized.
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http://dx.doi.org/10.14814/phy2.70151 | DOI Listing |
Physiol Rep
January 2025
Department of Biology, Slippery Rock University of Pennsylvania, Slippery Rock, Pennsylvania, USA.
Melatonin is a multifunctional biomolecule with demonstrated stimulatory, inhibitory, and antioxidant effects, including both receptor-mediated and receptor-independent mechanisms of action. One of its more perplexing effects is the disruption of regeneration in planaria. Head regeneration in planaria is a remarkable phenomenon in which stem cells (neoblasts) migrate to the wound site, proliferate, then differentiate into all functional tissue types within days of injury.
View Article and Find Full Text PDFAdv Skin Wound Care
January 2025
Keith Gordon Harding, Mb ChB, CBE, FRCGP, FRCP, FRCS, FLSW, is Professor Emeritus Cardiff University, Cardiff, Wales; Adjunct Professor Monash University Malaysia, Subang Jaya, Selangor, Malaysia; and Co-Founder and Editor in Chief of the International Wound Journal. Melissa Blow, BSc, is Principal Podiatrist, South East Wales Vascular Network, Aneurin Bevan University Health Board, Cardiff, Wales. Faye Ashton, BSc, is Vascular Research Nurse, Leicester Biomedical Research Centre, Glenfield University Hospital, Leicester, United Kingdom. David Bosanquet, MD, is Consultant Vascular Surgeon, South East Wales Vascular Network, Aneurin Bevan University Health Board. Acknowledgments: The authors acknowledge the assistance of Firstkind Ltd, Hawk House, Peregrine Business Park, Gomm Road, High Wycombe, United Kingdom HP13 7DL for sponsoring the study (grant ref: FSK-SPECKLE-001) and provided the NMES devices for the trial. Keith Harding has received payments for consulting work from Firstkind Ltd. The authors have disclosed no other financial relationships related to this article. Submitted November 28, 2023; accepted in revised form April 17, 2024.
Objective: To determine if intermittent neuromuscular electrostimulation (NMES) of the common peroneal nerve increases microvascular flow and pulsatility in and around the wound bed of patients with combined venous and arterial etiology.
Methods: Seven consenting participants presenting with mixed etiology leg ulcers participated in this study. Microvascular flow and pulsatility was measured in the wound bed and in the skin surrounding the wound using laser speckle contrast imaging.
J Cell Biochem
January 2025
Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, Zhejiang, China.
tRNA-derived fragments (tRFs) are a newly recognized class of small noncoding RNAs (sncRNAs) that play significant roles in various diseases. The Wnt pathway plays a key role in various physiological processes such as embryonic development, tissue renewal and regeneration. In the regulation of Wnt/β-catenin, Forkhead box k1(FOXK1), Frizzled class receptor 3 (FZD3), and Wnt5b can be targeted and inhibited by three tRFs: tRF3008A targets FOXK1 to inhibit colorectal cancer (CRC), 5'-tiRNAVal targets FZD3 to inhibit breast cancer (BrC), and tRF-22-8BWS7K092 targets Wnt5b to induce ferroptosis in lung cells.
View Article and Find Full Text PDFFront Med (Lausanne)
January 2025
Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Tongji Research Institute of Stomatology, Department of Prosthodontics, Shanghai Tongji Stomatological Hospital, Dental School, Tongji University, Shanghai, China.
Background: The conventional treatment for locally advanced head and neck squamous cell carcinoma (LA-HNSCC) is surgery; however, the efficacy of definitive chemoradiotherapy (CRT) remains controversial.
Objective: This study aimed to evaluate the ability of deep learning (DL) models to identify patients with LA-HNSCC who can achieve organ preservation through definitive CRT and provide individualized adjuvant treatment recommendations for patients who are better suited for surgery.
Methods: Five models were developed for treatment recommendations.
Facial Plast Surg
January 2025
Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, New York.
Exosomes have emerged as a promising therapeutic frontier in facial plastic surgery. Preclinical studies have demonstrated their ability to modulate wound healing, skin rejuvenation, hair growth, and nerve regeneration. Early clinical evidence suggests potential benefits in enhancing recovery after laser resurfacing, treating acne scars, and promoting hair growth.
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