Comments on"Comparison of efficacy and safety of intralesional triamcinolone and combination of triamcinolone with 5-fluorouracil in the treatment of keloids and hypertrophic scars: Randomisedcontrol trial"

Concentration-Dependent Inhibition of Hypertrophic Scar Formation by Botulinum Toxin Type A in a Rabbit Ear Model

BACKGROUND

Hypertrophic scar (HS), as a disappointing result of wound healing, adversely affects the patient, both physically and psychologically. Botulinum toxin type A (BTXA) has been revealed to prevent and improve HS. We conducted this study to assess the effect of different BTXA concentrations on inhibiting HS in a rabbit ear model.

METHODS

Eight healthy New Zealand long-eared rabbits were included in the experiment for modeling. Four wounds of 1 cm in diameter were created on both ears, which separately received an injection of a given BTXA concentration immediately after surgery. On postoperative days 40, scar tissue was obtained and subjected to hematoxylin and eosin (HE) staining for the hypertrophic index (HI) and immunohistochemical staining for CD31, Ki67, and transforming growth factor-beta 1 (TGF-β1) expression. The HI was assessed for scar proliferation, and CD31 and Ki67 expression were used to assess the effect of BTXA on angiogenesis and fibroblast proliferation, respectively.

RESULTS

All rabbits healed well without infection or mortality. From the HE staining, the HI showed a significant decrease with increasing BTXA concentration (p < 0.05). BTXA also inhibited angiogenesis and TGF-β1 expression in a concentration-dependent manner, with significant differences between the groups (p < 0.05). BTXA inhibited fibroblast proliferation with increasing BTXA concentration. However, there was no significant difference between the 0.5 U/0.1 ml and 0 U/0.1 ml groups (p > 0.05).

CONCLUSION

Immediate postoperative BTXA injection inhibited angiogenesis, fibroblast proliferation, and TGF-β1 expression in a concentration-dependent manner, thus suppressing HS formation in rabbit ears.

NO LEVEL ASSIGNED

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Update on management of keloid and hypertrophic scars: A systemic review

Numerous therapeutic strategies have been described for prevention and reduction of hypertrophic scars and keloids, but none of the treatments is effective in all patients. No universal consensus in treatment regimen has been established, and there is limited evidence-based literature to guide the correct management. The process of scar development is complex and requires deeper understanding of the molecular mechanisms that cause their development and recurrences. Despite many available modes of targeting keloid and hypertrophic scars, yet they remain an ongoing challenge to patients and clinicians. To date, no one therapy has been universally accepted as the gold standard for the treatment of all excessive scars nor has the capability of complete scar resolution The search of literature included peer-reviewed articles including clinical trials and scientific reviews. Literature was identified from electronic databases (MEDLINE/PubMed) through May 2021 and references of respective articles and only the articles published in English language were included.

LncRNA TUG1 exhibits pro-fibrosis activity in hypertrophic scar through TAK1/YAP/TAZ pathway via miR-27b-3p

Hypertrophic Scar (HS) is a complicated fibrotic disease. In addition, its pathogenesis is still to be further explored. Long non-coding RNAs (lncRNAs) have been proved to be participated in multiple diseases, including HS. However, the role of lncRNA TUG1 in HS remains unclear. The expression level of RNA and protein in cells were detected by q-PCR and western blot, respectively. MTT assay was performed to test the cell proliferation. Cell migration was detected by transwell assay. Cell apoptosis was measured by flow cytometry. Dual luciferase report assay and RNA pull down were used to verify the relationship between TUG1, miR-27b-3p and TAK1.TUG1 and TAK1 were upregulated in HS, while miR-27b-3p was downregulated. Knockdown of TUG1 significantly suppressed the proliferation and migration and induced the apoptosis of HS fibroblasts (HSF). In addition, silencing of TUG1 notably inhibited the extracellular matrix (ECM) biosynthesis in HSF. Overexpression of miR-27b-3p has the same effect on HS as that of TUG1 knockdown. Meanwhile, TUG1 could sponge miR-27b-3p, and TAK1 was the direct target of miR-27b-3p. Furthermore, knockdown of TUG1 significantly suppressed the fibrosis in HS via miR-27b-3p/TAK1/YAP/TAZ axis mediation. LncRNA TUG1 promotes the fibrosis in HS via sponging miR-27b-3p and then activates TAK1/YAP/TAZ pathway, which may serve as a potential target for treatment of HS.