TY - JOUR
T1 - Protopanaxatriol activates EGFR and HER2 to strengthen the molecules of skin protection in human keratinocytes
AU - You, Long
AU - Shen, Ting
AU - Hu, Weicheng
AU - Cho, Jae Youl
N1 - Publisher Copyright:
© 2023 Elsevier GmbH
PY - 2024/1
Y1 - 2024/1
N2 - Background: Protopanaxatriol (PPT) is an important ginsenoside produced by ginseng, a tonic plant used in many areas. PPT has beneficial effects against many disease states including inflammation, diabetes, and cancer. However, PPT's protective effects on skin integrity have been rarely studied. Previously, we reported that PPT can maintain skin moisture through activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways. However, the cellular targets for enhancing skin moisturizing effects via PPT are still unknown. Purpose: We wanted to identify the upstream targets of PPT on upregulating moisturizing factor (HAS-2) expression. Study design: We investigated which upstream proteins can be directly stimulated by PPT to modulate NF-κB, MAPKs and other signaling cascades. Then, the targeted proteins were overexpressed to check the relationship with HAS-2. Next, the cellular thermal shift assay (CETSA) was conducted to check the relationship between targeted proteins and PPT. Methods: A human keratinocyte HaCaT were employed to measure the levels of moisturizing factors and the signaling proteins activated by PPT. Transfection conditions were established with DNA constructs expressing epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) and their mutants prepared by site-directed mutagenesis. Further investigation on molecular mechanisms was conducted by RT-PCR, luciferase reporter gene assay, CETSA, or Western blot. Results: We found that PPT can activate the phosphorylation of EGFR and HER2. These stimulations caused Src phosphorylation, which resulted in the activation of phosphoinositide 3-kinases (PI3K)/pyruvate dehydrogenase kinase 1 (PDK1)/protein kinase B (AKT)/NF-κB and MAPKs signaling cascades. Additionally, EGFR and HER2 activation resulted in phosphorylation of signal transducer and activator of transcription 3 (STAT3) and calcium/calmodulin-dependent protein kinase II (CaMKII). This induced the AMP-activated protein kinase alpha (AMPKα) signaling pathway. Additionally, PPT blocked peroxisome proliferator activated receptor gamma (PPARγ), which also contributed to the phosphorylation of Src. Conclusion: Overall, we first found that PPT offers excellent protection of the skin barrier and hydrogen supply in keratinocytes. Moreover, growth factor receptors such as EGFR and HER2 were revealed to be central enzymes to be directly targeted by PPT. These results suggest a potentially valuable role as a cosmetic ingredient.
AB - Background: Protopanaxatriol (PPT) is an important ginsenoside produced by ginseng, a tonic plant used in many areas. PPT has beneficial effects against many disease states including inflammation, diabetes, and cancer. However, PPT's protective effects on skin integrity have been rarely studied. Previously, we reported that PPT can maintain skin moisture through activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways. However, the cellular targets for enhancing skin moisturizing effects via PPT are still unknown. Purpose: We wanted to identify the upstream targets of PPT on upregulating moisturizing factor (HAS-2) expression. Study design: We investigated which upstream proteins can be directly stimulated by PPT to modulate NF-κB, MAPKs and other signaling cascades. Then, the targeted proteins were overexpressed to check the relationship with HAS-2. Next, the cellular thermal shift assay (CETSA) was conducted to check the relationship between targeted proteins and PPT. Methods: A human keratinocyte HaCaT were employed to measure the levels of moisturizing factors and the signaling proteins activated by PPT. Transfection conditions were established with DNA constructs expressing epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) and their mutants prepared by site-directed mutagenesis. Further investigation on molecular mechanisms was conducted by RT-PCR, luciferase reporter gene assay, CETSA, or Western blot. Results: We found that PPT can activate the phosphorylation of EGFR and HER2. These stimulations caused Src phosphorylation, which resulted in the activation of phosphoinositide 3-kinases (PI3K)/pyruvate dehydrogenase kinase 1 (PDK1)/protein kinase B (AKT)/NF-κB and MAPKs signaling cascades. Additionally, EGFR and HER2 activation resulted in phosphorylation of signal transducer and activator of transcription 3 (STAT3) and calcium/calmodulin-dependent protein kinase II (CaMKII). This induced the AMP-activated protein kinase alpha (AMPKα) signaling pathway. Additionally, PPT blocked peroxisome proliferator activated receptor gamma (PPARγ), which also contributed to the phosphorylation of Src. Conclusion: Overall, we first found that PPT offers excellent protection of the skin barrier and hydrogen supply in keratinocytes. Moreover, growth factor receptors such as EGFR and HER2 were revealed to be central enzymes to be directly targeted by PPT. These results suggest a potentially valuable role as a cosmetic ingredient.
KW - EGFR
KW - HER2
KW - Keratinocyte
KW - Protopanaxatriol
KW - Skin barrier
KW - Skin hydration
UR - https://www.scopus.com/pages/publications/85176095072
U2 - 10.1016/j.phymed.2023.155167
DO - 10.1016/j.phymed.2023.155167
M3 - Article
C2 - 37952408
AN - SCOPUS:85176095072
SN - 0944-7113
VL - 123
JO - Phytomedicine
JF - Phytomedicine
M1 - 155167
ER -