scholarly journals Piper retrofractumVahl. Extract, as a PPARδand AMPK Activator, Suppresses UVB-Induced Photoaging through Mitochondrial Biogenesis and MMPs Inhibition in Human Dermal Fibroblasts and Hairless Mice

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Jungon Yun ◽  
Changhee Kim ◽  
Mi-Bo Kim ◽  
Jae-Kwan Hwang

Photoaging occurs by UVB-irradiation and involves production of reactive oxygen species (ROS) and overexpression of matrix metalloproteinases (MMPs), leading to extracellular matrix damage.Piper retrofractumVahl. is used as a traditional medicine for antiflatulence, expectorant, sedative, and anti-irritant; however, its antiphotoaging effect has not yet been studied. The current study investigated the antiphotoaging effect of standardizedPiper retrofractumextract (PRE) on UVB-damaged human dermal fibroblasts and hairless mouse skin. PRE treatment activated the peroxisome proliferator-activated receptor delta (PPARδ) and the adenosine monophosphate-activated protein kinase (AMPK), consequently upregulating mitochondrial synthesis and reducing ROS production. Additionally, PRE inhibited MMPs expression via suppressing mitogen-activated protein kinase (MAPK) and activator protein-1 (AP-1). PRE downregulated UVB-induced inflammatory reactions by inhibiting the nuclear factor-kappa B (NF-κB) activity. PRE also enhanced transforming growth factor-beta (TGF-β) and the Smad signaling pathway, thereby promoting procollagen gene transcription. Furthermore, oral administration of PRE (300 mg/kg/day) similarly regulated the signaling pathways and increased antioxidant enzyme expression, thus attenuating physiological deformations, such as wrinkle formation and erythema response. Collectively, these results suggest that PRE acts as a potent antiphotoaging agent via PPARδand AMPK activation.

Open Biology ◽  
2013 ◽  
Vol 3 (6) ◽  
pp. 130067 ◽  
Author(s):  
Gopal P. Sapkota

The signalling pathways downstream of the transforming growth factor beta (TGFβ) family of cytokines play critical roles in all aspects of cellular homeostasis. The phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) has been implicated in TGFβ-induced epithelial-to-mesenchymal transition and apoptosis. The precise molecular mechanisms by which TGFβ cytokines induce the phosphorylation and activation of p38 MAPK are unclear. In this study, I demonstrate that TGFβ-activated kinase 1 (TAK1/MAP3K7) does not play a role in the TGFβ-induced phosphorylation and activation of p38 MAPK in MEFs and HaCaT keratinocytes. Instead, RNAi -mediated depletion of MAP3K4 and MAP3K10 results in the inhibition of the TGFβ-induced p38 MAPK phosphorylation. Furthermore, the depletion of MAP3K10 from cells homozygously knocked-in with a catalytically inactive mutant of MAP3K4 completely abolishes the TGFβ-induced phosphorylation of p38 MAPK, implying that among MAP3Ks, MAP3K4 and MAP3K10 are sufficient for mediating the TGFβ-induced activation of p38 MAPK.


2007 ◽  
Vol 404 (2) ◽  
pp. 327-336 ◽  
Author(s):  
Lingli Li ◽  
Trias Asteriou ◽  
Berit Bernert ◽  
Carl-Henrik Heldin ◽  
Paraskevi Heldin

The glycosaminoglycan hyaluronan is important in many tissuerepair processes. We have investigated the synthesis of hyaluronan in a panel of cell lines of fibroblastic and epithelial origin in response to PDGF (platelet-derived growth factor)-BB and other growth factors. Human dermal fibroblasts exhibited the highest hyaluronan-synthesizing activity in response to PDGF-BB. Analysis of HAS (hyaluronan synthase) and HYAL (hyaluronidase) mRNA expression showed that PDGF-BB treatment induced a 3-fold increase in the already high level of HAS2 mRNA, and increases in HAS1 and HYAL1 mRNA, whereas the levels of HAS3 and HYAL2 mRNA were not affected. Furthermore, PDGF-BB also increased the amount and activity of HAS2 protein, but not of HYAL1 and HYAL2 proteins. Using inhibitors for MEK1/2 [MAPK (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) kinase 1/2] (U0126) and for PI3K (phosphoinositide 3-kinase) (LY294002), as well as the SN50 inhibitor, which prevents translocation of the active NF-κB (nuclear factor κB) to the nucleus, we observed a complete inhibition of both HAS2 transcriptional activity and hyaluronan synthesis, whereas inhibitors of other signalling pathways were without any significant effect. TGF-β1 (transforming growth factor-β1) did not increase the activity of hyaluronan synthesis in dermal fibroblasts, but increased the activity of HYALs. Importantly, inhibition of hyaluronan binding to its receptor CD44 by the monoclonal antibody Hermes-1, inhibited PDGF-BB-stimulated [3H]thymidine incorporation of dermal fibroblasts. We conclude that the ERK MAPK and PI3K signalling pathways are necessary for the regulation of hyaluronan synthesis by PDGF-BB, and that prevention of its binding to CD44 inhibits PDGF-BB-induced cell growth.


2021 ◽  
pp. 815-820
Author(s):  
M KAŇUCHOVÁ ◽  
L URBAN ◽  
N MELEGOVÁ ◽  
M ČOMA ◽  
B DVOŘÁNKOVÁ ◽  
...  

Transforming growth factor beta 1 (TGF-β1) is a pro-fibrotic cytokine with a key role in wound repair and regeneration, including induction of fibroblast-to-myofibroblast transition. Genistein is a naturally occurring selective estrogen receptor modulator with promising anti-fibrotic properties. In the present study we aimed to investigate whether genistein modulates TGF-β1 (canonical and non-canonical) signaling in normal dermal fibroblasts at the protein level (Western blot and immunofluo-rescence). We demonstrated that TGF-β1 induces the myofibroblast-like phenotype in the studied fibroblast signaling via canonical (SMAD) and non-canonical (AKT, ERK1/2, ROCK) pathways. Genistein induced only ERK1/2 expression, whereas the combination of TGF-β1 and genistein attenuated the ERK1/2 and ROCK signaling. Of note, the other studied pathways remained almost unaffected. From this point of view, genistein does not impair conversion of normal fibroblasts to myofibroblast-like cells.


1992 ◽  
Vol 284 (3) ◽  
pp. 629-632 ◽  
Author(s):  
A Mauviel ◽  
C H Evans ◽  
J Uitto

Leukoregulin (LR), a T-cell-derived growth factor, modulates fibroblast functions in vitro [Mauviel, Rédini, Hartmann, Loyau & Pujol (1991) J. Cell Biol. 113, 1455-1462]. In the present study, incubation of human dermal fibroblasts with LR (0.1-2 units/ml) resulted in decreases in the mRNA steady-state levels for alpha 1(I), alpha 2(I) and alpha 1(III), but not alpha 2(V), collagen genes. LR also down-regulated alpha 2(I) collagen promoter activity in transient cell transfections of control cells as well as those incubated with transforming growth factor-beta, a potent up-regulator of collagen type I gene expression. Thus LR is a strong inhibitor of type I collagen gene expression, acting at the level of transcription.


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