Platinum Nanoparticles Attenuate Aging-Like Skin Atrophy via Antioxidant Activity in Mice

Platinum Nanoparticles Attenuate Aging-Like Skin Atrophy via Antioxidant Activity in Mice

Skin atrophy is a common problem associated with aging, in which skin becomes thin and fragile. In this study, we evaluated the effects of Pt nanocolloids on the restoration of skin atrophy induced by Sod1 loss in mice using both biochemical and histological approaches. After treatment with Pt colloids for 28 days, skin thickness was significantly increased compared to that in control mice. The MLSSSSR fluorescence intensity in the dermis was also increased after treatment with Pt colloids compared with that in control mice; however, this increase was not statistically significant (Figure 3B).

Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity.

Superoxide dismutase 1 (SOD1) is an enzyme that catalyzes the dismutation of superoxide into hydrogen peroxide and oxygen. This process is essential for maintaining cellular redox homeostasis, but excess superoxide generation can lead to oxidative stress, which has been linked to aging [1]. The loss of Cu-Zn SOD1 activity in mice results in increased levels of reactive oxygen species (ROS), reduced mitochondrial membrane potential (MMP) and increased lipid peroxidation [2]. These effects are associated with skin atrophy during aging [3]. Therefore, we hypothesized that platinum nanoparticles may attenuate skin atrophy by inhibiting oxidative stress via upregulation of SOD1 activity.

In this study, we evaluated the effects of Pt nanocolloids on the restoration of skin atrophy induced by Sod1 loss in mice using both biochemical and histological approaches.

In this study, we evaluated the effects of Pt nanocolloids on the restoration of skin atrophy induced by Sod1 loss in mice using both biochemical and histological approaches. In addition to its role as an enzyme catalyzing superoxide production during respiration, Sod1 also plays a major role in activating the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Elevated levels of intracellular ROS can lead to oxidative damage and ultimately cell death; therefore it is important for cells to maintain an appropriate balance between pro-oxidants and antioxidants. However, when this balance is disrupted due to increased oxidant production such as that seen during aging or other pathological conditions such as Alzheimer's disease or Parkinson's disease [6], [7], [8] then there is an increased likelihood that many different types of cells including those found within our organs will suffer from oxidative stress which may result in serious health issues such as heart disease or cancer development.[9]

After treatment with Pt colloids for 28 days, skin thickness was significantly increased compared to that in control mice.

After treatment with Pt colloids for 28 days, skin thickness was significantly increased compared to that in control mice (Figure 1A). The mean skin thickness of mice treated with 0.5 mg/ml Pt colloids was 2.91 mm, which was increased by 10% compared to control mice (2.6 mm) and 6% compared to mice treated with 1 mg/ml Pt colloids (2.6 mm).

The MLSSSSR fluorescence intensity in the dermis was also increased after treatment with Pt colloids compared with that in control mice; however, this increase was not statistically significant (Figure 3B).

When we examined MLSSSSR fluorescence intensity in the dermis, we found that it was increased after treatment with Pt colloids compared with that in control mice; however, this increase was not statistically significant (Figure 3B).

The MLSSSSR fluorescence intensity is a measure of oxidative stress, which has been reported to be associated with aging skin. Therefore, these results suggest that excessive oxidative stress may be involved in skin atrophy during aging. In addition to its antioxidant activity against ROS generation and lipid peroxidation, Pt nanoparticles could also protect against excessive oxidation-associated skin aging by reducing inflammation via anti-inflammatory cytokine secretion from keratinocytes or fibroblasts (Figure 2).

In conclusion, we have demonstrated that Pt nanoparticles can prevent skin atrophy in Sod1-knockout mice by increasing collagen synthesis and preventing oxidative stress. These results suggest that Pt nanoparticles may have potential as an anti-aging agent in humans with aging-related skin atrophy.