Assessing the Anti-Inflammatory Potential of PTT-6® in UVB-Induced Keratinocyte Damage

Introduction

Ultraviolet B (UVB) radiation is a well-established inducer of oxidative stress and inflammation in the epidermis of the human skin and scalp primarily through the activation of keratinocytes. UVB exposure of keratinocytes in vitro activates the synthesis of various cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), IL-6, IL-8 and IL-10 (1–3).

Among these, TNF-α plays a crucial role in skin and follicle cell damage and immune response through multiple mechanisms. For example, TNF-α induced by UVB, activates nearly all endothelial cells and keratinocytes to display cell adhesion molecules, thus recruiting inflammatory cells that secrete elastases and collagenases, resulting to damage and aging of the skin (4). Furthermore,  TNF-α promotes apoptosis, lymphocyte activation, and hyperproliferative skin disorders(5,6). This study aims to assess the potential anti-inflammatory properties of PTT-6®  by measuring TNF-α inhibition in UVB-induced normal human epidermal keratinocytes (NHEK) cells.

Method

A PTT-6® sample was provided by CellResearch Corp. NHEK cells were cultured in 6-well plates, exposed to UVB (40 mJ/cm²), and treated with PTT-6® at serial dilutions (2-64-fold) or Vitamin D (4 µM) as a positive control. TNF-α levels were measured using enzyme-linked immunosorbent assay (ELISA) following standard protocols. Absorbance was read at 450 nm using a microplate reader.

Results

Stem cell-conditioned media (SCCM) has emerged as promising therapeutic agents due to their ability to modulate inflammation and enhance tissue regeneration. It is therefore seen as a promising therapeutic agent due to its ability to modulate inflammation and enhance tissue regeneration (7) . As a cell-free cord lining conditioned media, PTT-6® contains a variety of growth factors, cytokines, and extracellular vesicles secreted by stem cells, which can exert paracrine effects on target cells.

In this study, UVB exposure significantly elevated TNF-α production in keratinocytes. Treatment with PTT-6® was shown to result in a dose-dependent reduction in TNF-α levels, with the most significant inhibition observed at 2-fold and 4-fold dilutions. These findings suggest that PTT-6® contains potent anti-inflammatory properties, and this benefit may potentially affect skin and hair follicle cells when topically applied.

Figure 1. Effects of PTT-6® on TNF-α Levels in NHEK Cells Following UVB Exposure

Conclusion

PTT-6® showed the strongest inhibition of UVB-induced TNF-a production in keratinocytes at dilution times of 2,4 and 8. Its efficacy at lower dilution highlights its potential as a candidate for mitigating UVB-induced skin inflammation. These findings suggest that PTT-6® contains potent anti-inflammatory properties, and this benefit may potentially affect skin and hair follicle cells when topically applied.

Reference

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