Treatment of Acute Wounds With Recombinant Human-Like Collagen and Recombinant Human-Like Fibronectin in C57BL/6 Mice Individually or in Combination

Asiatic acid improves the damage of HaCaT cells induced by nitrogen mustard through inhibiting endoplasmic reticulum stress

Nitrogen mustard (NM) belongs to vesicant agents. Blisters are one of the important characteristics of NM skin damage. It is urgent to further elucidate the mechanism and develop effective countermeasures for the skin damage induced by NM. The endoplasmic reticulum (ER) is an important intracellular organelle, playing an important role in maintaining cellular homeostasis. In this study, we explored the role of endoplasmic reticulum stress (ERS) and the protective effect of asiatic acid (AA) in the HaCaT cells induced by NM. It was found that the key regulatory proteins of ERS, such as glucose regulated protein 78 (GRP78), X-box binding protein 1 (XBP1), inositol requiring enzyme 1 (IRE1), Phospho-IRE1 (pIRE1), and TNF receptor associated factor 2 (TRAF2) were increased respectively in HaCaT cells exposed to NM compared with those of the control group, showing an increasing trend with the increase of NM exposure concentration and exposure time. Additionally, the protein expression of Caspase-3 and the Cleaved-Caspase-3 was also increased by NM in HaCaT cells, resulting in the apoptosis of HaCaT cells. Meanwhile, the content of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) was also increased in HaCaT cells exposed to NM. Further study showed that AA pretreatment could decrease the protein expression of GRP78, XBP1 and IRE1, pIRE1, TRAF2, Caspase-3, and Cleaved-Caspase-3. And moreover, AA also could reduce the content of TNF-α and IL-6. Overall, the present study showed that AA played an important protective effect in HaCaT cells exposed to NM through the inhibition of the ERS-induced apoptosis and inflammatory response.

Polycaprolactone Fiber and Laminin and Collagen IV Protein Incorporation in Implants Enhances Wound Healing in a Novel Mouse Skin Splint Model

Wound healing is an intricate process involving multiple cells and distinct phases, presenting challenges for comprehensive investigations. Currently available treatments for wounds have limited capacity to fully restore tissue and often require significant investments of time in the form of repetitive dressing changes and/or reapplications. This article presents a novel study that aims to enhance wound healing by developing biomaterial scaffolds using Medpor®, a porous polyethylene implant, as a model scaffold. The study incorporates electrospun poly(e-caprolactone) (PCL) fibers and a protein mixture (PM) containing collagen IV and laminin onto the Medpor® scaffolds. To evaluate the impact of these implants on wound healing, a unique splinted wound model in mice is employed. The wounds were evaluated for closure, inflammation, collagen deposition, angiogenesis, epithelialization, and proliferation. The results show that wounds treated with Medpor® + PCL + PM implants demonstrate accelerated closure rates, improved epithelialization, and enhanced angiogenesis compared to other implant groups. However, there were no significant differences observed in collagen deposition and inflammatory response among the implant groups. This study provides valuable insights into the potential benefits of incorporating PCL fibers and a PM onto scaffolds to enhance wound healing. Furthermore, the developed splinted wound model with integrated implants offers a promising platform for future studies on implant efficacy and the advancement of innovative wound healing strategies.

A Novel Recombinant Human Filaggrin Segment (rhFLA-10) Alleviated a Skin Lesion of Atopic Dermatitis

Atopic dermatitis (AD), a prevalent chronic inflammatory skin disorder, is marked by impaired skin barrier function and persistent pruritus. It significantly deteriorates patients' quality of life, making it one of the most burdensome non-lethal skin disorders. Filaggrin plays a crucial role in the pathophysiology of barrier disruption in AD, interacting with inflammatory mediators. It is an integral part of the extracellular matrix architecture, serving to protect the skin barrier and attenuate the inflammatory cascade. In this study, we engineered a novel recombinant human filaggrin (rhFLA-10) expression vector, which was subsequently synthesized and purified. In vitro and ex vivo efficacy experiments were conducted for AD. rhFLA-10, at low concentrations (5 to 20 μg/mL), was non-toxic to HACaT cells, significantly inhibited the degranulation of P815 mast cells, and was readily absorbed by cells, thereby exerting a soothing therapeutic effect. Furthermore, rhFLA-10 demonstrated anti-inflammatory properties (p < 0.05). In vivo, efficacy experiments further substantiated that rhFLA-10 could effectively ameliorate AD in mice and facilitate the repair of damaged skin (p < 0.001). These findings underscore the considerable potential of rhFLA-10 in the treatment of AD.

Recombinantly expressed rhFEB remodeled the skin defect of db/db mice

Fibronectin (FN) and collagen are vital components of the extracellular matrix (ECM). These proteins are essential for tissue formation and cell alignment during the wound healing stage. In particular, FN interacts with collagens to activate various intracellular signaling pathways to maintain ECM stability. A novel recombinant extra domain-B fibronectin (EDB-FN)-COL3A1 fusion protein (rhFEB) was designed to mimic the ECM to promote chronic and refractory skin ulcer wound healing. rhFEB significantly enhanced cell adhesion and migration, vascular ring formation, and the production of new collagen I (COL1A1) in vitro. rhFEB decreased M1 macrophages and further modulated the wound microenvironment, which was confirmed by the treatment of db/db mice with rhFEB. Accelerated wound healing was shown during the initial stages in rhFEB-treated db/db mice, as was enhanced follicle regeneration, re-epithelialization, collagen deposition, granulation, inflammation, and angiogenesis. The wound chronicity of diabetic foot ulcers (DFUs) remains the main challenge in current and future treatment. rhFEB may be a candidate molecule for regulating M1 macrophages during DFU healing. KEY POINTS: • A recombinant protein EDB-FN-collagen III (rhFEB) was highly expressed in Escherichia coli • rhFEB protein induces COL1A1 secretion in human skin fibroblasts • rhFEB protein accelerates diabetic wound healing.

Combination of fractional carbon dioxide laser with recombinant human collagen in periocular skin rejuvenation

BACKGROUND

The most visible sign of facial aging is often seen in the periocular area. However, periocular rejuvenation remains challenging due to the particularity of periocular anatomic locations.

AIMS

We aimed to evaluate the efficacy and safety of the fractional-ablative CO2 laser-facilitated recombinant human collagen permeation in periocular rejuvenation.

PATIENTS/METHODS

This 3-month prospective single-blinded and self-controlled trial enrolled 26 patients with periocular aging who underwent the treatments of fractional-ablative CO2 laser along with laser-facilitated recombinant human collagen permeation. Following the treatments, the patients were quantitatively assessed by various periocular skin aging indices before and after the treatment and monitored for any related adverse events.

RESULTS

The patients showed significant improvements with the periocular skin aging indices 3 months after the treatments, which were detailed with a 47.3% decrease in lower eyelid skin rhytids, a 41.4% decrease in the lower eyelid skin texture, a 35.0% decrease in the static crow's feet, a 29.3% decrease in the amount of upper eyelid laxity, and a 20.2% increase in the MRD1 as compared with baseline (p < 0.05). Moreover, total skin thickness under ultrasound was increased in both upper and lower eyelids (5.6% and 3.3%, p < 0.05, respectively). Moreover, six patients (23.1%, 6/26) had erythema for 2 weeks, and two (2/26, 7.7%) had mild hyperpigmentation for 3 months.

CONCLUSIONS

Fractional-ablative CO2 laser combined with laser-facilitated recombinant human collagen permeation can be a safe and effective treatment for periocular rejuvenation.