scholarly journals Leptin Enhances Human β-Defensin-2 Production in Human Keratinocytes

Endocrinology ◽  
2008 ◽  
Vol 149 (10) ◽  
pp. 5189-5198 ◽  
Author(s):  
Naoko Kanda ◽  
Shinichi Watanabe

Leptin, an adipocyte-derived cytokine/hormone, modulates innate and adaptive immunity. Human β-defensin-2 (hBD-2) produced by epidermal keratinocytes promotes cutaneous antimicrobial defense, inflammation, and wound repair. We examined the in vitro effects of leptin on hBD-2 production in human keratinocytes. hBD-2 secretion and mRNA expression were analyzed by ELISA and RT-PCR, respectively. Although leptin alone was ineffective, it enhanced IL-1β-induced hBD-2 secretion and mRNA expression in keratinocytes. IL-1β- and IL-1β plus leptin-induced hBD-2 production both were suppressed by antisense oligonucleotides against nuclear factor-κB (NF-κB) p50 and p65; the latter was also suppressed by antisense signal transducer and activator of transcription (STAT)1 and STAT3. IL-1β enhanced the transcriptional activity of NF-κB, whereas leptin enhanced STAT1 and STAT3 activity. The p38 MAPK inhibitor SB202190 suppressed IL-1β- and IL-1β plus leptin-induced hBD-2 production, IL-1β-induced NF-κB activity, and leptin-induced STAT1 and STAT3 activity; contrastingly, the Janus kinase (JAK) 2 inhibitor AG490 suppressed IL-1β plus leptin-induced hBD-2 production and leptin-induced STAT1 and STAT3 activity. IL-1β induced serine phosphorylation of inhibitory κBα, STAT1, and STAT3. Leptin induced tyrosine and serine phosphorylation of STAT1 and STAT3, both of which were suppressed by AG490, and serine phosphorylation was also suppressed by SB202190. IL-1β or leptin individually induced threonine/tyrosine phosphorylation of p38 MAPK, whereas only leptin induced tyrosine phosphorylation of JAK2, suggesting that leptin may enhance hBD-2 production in keratinocytes by activating STAT1 and STAT3 via JAK2 and p38 MAPK in cooperation with NF-κB, which is activated by IL-1β. Leptin may promote cutaneous antimicrobial defense, inflammation, and wound repair via hBD-2.

2007 ◽  
Vol 293 (6) ◽  
pp. C1916-C1923 ◽  
Author(s):  
Naoko Kanda ◽  
Shinichi Watanabe

The anti-microbial peptide human β-defensin-2 (hBD-2), produced by epidermal keratinocytes, plays pivotal roles in anti-microbial defense, inflammatory dermatoses, and wound repair. hBD-2 induces histamine release from mast cells. We examined the in vitro effects of histamine on hBD-2 production in normal human keratinocytes. Histamine enhanced TNF-α- or IFN-γ-induced hBD-2 secretion and mRNA expression. Histamine alone enhanced transcriptional activities of NF-κB and activator protein-1 (AP-1) and potentiated TNF-α-induced NF-κB and AP-1 activities or IFN-γ-induced NF-κB and STAT1 activities. Antisense oligonucleotides against NF-κB components p50 and p65, AP-1 components c-Jun and c-Fos, or H1 antagonist pyrilamine suppressed hBD-2 production induced by histamine plus TNF-α or IFN-γ. Antisense oligonucleotide against STAT1 only suppressed hBD-2 production induced by histamine plus IFN-γ. Histamine induced serine phosphorylation of inhibitory NF-κBα (IκBα) alone or together with TNF-α or IFN-γ. Histamine induced c-Fos mRNA expression alone or together with TNF-α, whereas it did not further increase c-Jun mRNA levels enhanced by TNF-α. Histamine induced serine phosphorylation of STAT1 alone or together with IFN-γ, whereas it did not further enhance IFN-γ-induced tyrosine phosphorylation of STAT1. The histamine-induced serine phosphorylation of STAT1 was suppressed by MAPKK (MEK) inhibitor PD98059. These results suggest that histamine stimulates H1 receptor and potentiates TNF-α- or IFN-γ-induced hBD-2 production dependent on NF-κB, AP-1, or STAT1 in human keratinocytes. Histamine may potentiate anti-microbial defense, skin inflammation, and wound repair via the induction of hBD-2.


Author(s):  
A. R. Crooker ◽  
M. C. Myers ◽  
T. L. Beard ◽  
E. S. Graham

Cell culture systems have become increasingly popular as a means of screening toxic agents and studying toxic mechanisms of drugs and other chemicals at the cellular and subcellular levels. These in vitro tests can be conducted rapidly in a broad range of relevant mammalian culture systems; a variety of biological and biochemical cytotoxicity endpoints can be examined. The following study utilized human keratinocytes to evaluate the relative cytotoxicities of nitrofurazone (NF) and silver sulfadiazine (SS), the active ingredients of FURACIN(R) Topical Cream and SILVADENE(R) Cream, respectively. These compounds are anti-infectives used in the treatment of burn patients. Cell ultrastructure and elemental composition were utilized as cytotoxicity endpoints.Normal Human Epidermal Keratinocytes (HK) were prepared from the EpiPackTM culture system (Clonetics Corporation, Boulder, CO). For scanning electron microscopy (SEM) and transmission electron microscopy (TEM), cells were seeded on sterile 35 mm Falcon plastic dishes; for elemental microanalysis, cells were plated on polished pyrolytic carbon discs (E. Fullam, Latham, NY) placed in the culture dishes.


Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2153
Author(s):  
Raffaella Marina Lecci ◽  
Isabella D’Antuono ◽  
Angela Cardinali ◽  
Antonella Garbetta ◽  
Vito Linsalata ◽  
...  

A wide variety of polyphenols are reported to have considerable antioxidant and skin photoprotective effects, although the mechanisms of action are not fully known. Environmentally friendly and inexpensive sources of natural bioactive compounds, such as olive mill wastewater (OMWW), the by-product of olive-oil processing, can be considered an economic source of bioactive polyphenols, with a range of biological activities, useful as chemotherapeutic or cosmeceutical agents. Green strategies, such as the process based on membrane technologies, allow to recover active polyphenols from this complex matrix. This study aims to evaluate the antioxidant, pro-oxidant, and photoprotective effects, including the underlying action mechanism(s), of the ultra-filtered (UF) OMWW fractions, in order to substantiate their use as natural cosmeceutical ingredient. Six chemically characterized UF-OMWW fractions, from Italian and Greek olive cultivar processing, were investigated for their antioxidant activities, measured by Trolox Equivalent Antioxidant Capacity (TEAC), LDL oxidation inhibition, and ROS-quenching ability in UVA-irradiated HEKa (Human Epidermal Keratinocytes adult) cultures. The photoprotective properties of UF-OMWW were assayed as a pro-oxidant-mediated pro-apoptotic effect on the UVA-damaged HEKa cells, which can be potentially involved in the carcinogenesis process. All the UF-OMWW fractions exerted an effective antioxidant activity in vitro and in cells when administered together with UV-radiation on HEKa. A pro-oxidative and pro-apoptotic effect on the UVA-damaged HEKa cells were observed, suggesting some protective actions of polyphenol fraction on keratinocyte cell cultures.


1999 ◽  
Vol 23 (2) ◽  
pp. 125-136 ◽  
Author(s):  
C Bignon ◽  
N Daniel ◽  
L Belair ◽  
J Djiane

The recent finding that sheep had long (l-oPRLR) and short (s-oPRLR) prolactin receptors provided new tools to further explore prolactin signaling to target genes. Here we used CHO cells transfected with l-oPRLR or s-oPRLR cDNAs to compare the activation of known key steps of prolactin signaling by the two receptors. We found that prolactin stimulated l-oPRLR tyrosine phosphorylation, although it lacked the last tyrosine residue found in other long prolactin receptors. In addition, l-oPRLR and s-oPRLR both responded to prolactin stimulation by (1) Janus kinase 2 (Jak2) tyrosine phosphorylation, (2) DNA-binding activation of signal transducer and activator of transcription 5 (STAT5), (3) stimulation of transcription from a promoter made of six repeats of STAT5-responsive sequence. However, although it contains STAT5-binding consensus sequences, the ovine beta-lactoglobulin promoter (-4000 to +40) was transactivated by l-oPRLR, but not by s-oPRLR. Taken together, our results indicate that activation of Jak2/STAT5 pathway alone is not sufficient to account for prolactin-induced transcription of this milk protein gene, and that sequences of its promoter, other than STAT5-specific sequences, account for the opposite transcriptional activation capabilities of l-oPRLR and s-oPRLR.


1990 ◽  
Vol 10 (5) ◽  
pp. 2359-2366
Author(s):  
D K Morrison ◽  
D R Kaplan ◽  
S G Rhee ◽  
L T Williams

We investigated the interaction of phospholipase C-gamma (PLC-gamma) with wild-type and mutant forms of the platelet-derived growth factor (PDGF) beta-receptor both in vivo and in vitro. After PDGF treatment of CHO cell lines expressing wild-type or either of two mutant (delta Ki and Y825F) PDGF receptors, PLC-gamma became tyrosine phosphorylated and associated with the receptor proteins. The receptor association and tyrosine phosphorylation of PLC-gamma correlated with the ability of these receptors to mediate ligand-induced phosphatidylinositol turnover. However, both the delta Ki and Y825F mutant receptors were deficient in transmitting mitogenic signals, suggesting that the PDGF-induced tyrosine phosphorylation and receptor association of PLC-gamma are not sufficient to account for the growth-stimulatory activity of PDGF. Wild-type and delta Ki mutant PDGF receptor proteins expressed with recombinant baculovirus vectors also associated in vitro with mammalian PLC-gamma. However, baculovirus-expressed c-fms, v-fms, c-src, and Raf-1 proteins failed to associate with PLC-gamma under similar conditions. Phosphatase treatment of the baculovirus-expressed PDGF receptor greatly decreased its association with PLC-gamma. This requirement for receptor phosphorylation was also observed in vivo, where PLC-gamma could not associate with a mutant PDGF receptor (K602A) defective in autophosphorylation. PLC-gamma also coimmunoprecipitated with two other putative receptor substrates, the serine-threonine kinase Raf-1 and the 85-kilodalton phosphatidylinositol-3' kinase, presumably through its association with the ligand-activated receptor. Furthermore, baculovirus-expressed Raf-1 phosphorylated purified PLC-gamma in vitro at sites which showed increased serine phosphorylation in vivo in response to PDGF. These results suggest that PDGF directly influences PLC activity by inducing the association of PLC-gamma with a receptor signaling complex, resulting in increased tyrosine and serine phosphorylation of PLC-gamma.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mariko Moriyama ◽  
Shunya Sahara ◽  
Kaori Zaiki ◽  
Ayumi Ueno ◽  
Koichi Nakaoji ◽  
...  

AbstractWound healing is regulated by complex interactions between the keratinocytes and other cell types including fibroblasts. Recently, adipose-derived mesenchymal stromal/stem cells (ASCs) have been reported to influence wound healing positively via paracrine involvement. However, their roles in keratinocytes are still obscure. Therefore, investigation of the precise effects of ASCs on keratinocytes in an in vitro culture system is required. Our recent data indicate that the epidermal equivalents became thicker on a collagen vitrigel membrane co-cultured with human ASCs (hASCs). Co-culturing the human primary epidermal keratinocytes (HPEK) with hASCs on a collagen vitrigel membrane enhanced their abilities for cell proliferation and adhesion to the membrane but suppressed their differentiation suggesting that hASCs could maintain the undifferentiated status of HPEK. Contrarily, the effects of co-culture using polyethylene terephthalate or polycarbonate membranes for HPEK were completely opposite. These differences may depend on the protein permeability and/or structure of the membrane. Taken together, our data demonstrate that hASCs could be used as a substitute for fibroblasts in skin wound repair, aesthetic medicine, or tissue engineering. It is also important to note that a co-culture system using the collagen vitrigel membrane allows better understanding of the interactions between the keratinocytes and ASCs.


2019 ◽  
Vol 20 (14) ◽  
pp. 3574 ◽  
Author(s):  
Hye-Sun Lim ◽  
Yu Jin Kim ◽  
Bu-Yeo Kim ◽  
Soo-Jin Jeong

The purpose of the present study was to evaluate the effects of bakuchiol on the inflammatory response and to identify the molecular mechanism of the inflammatory effects in a lipopolysaccharide (LPS)-stimulated BV-2 mouse microglial cell line and mice model. The production of prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) was measured by enzyme-linked immunosorbent assay. The mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TNF-α, and IL-6 was measured using reverse transcription–polymerase chain reaction analysis. Mitogen-activated protein kinase (MAPK) phosphorylation was determined by western blot analysis. In vitro experiments, bakuchiol significantly suppressed the production of PGE2 and IL-6 in LPS-stimulated BV-2 cells, without causing cytotoxicity. In parallel, bakuchiol significantly inhibited the LPS-stimulated expression of iNOS, COX-2, and IL-6 in BV-2 cells. However, bakuchiol had no effect on the LPS-stimulated production and mRNA expression of TNF-α or on LPS-stimulated c-Jun NH2-terminal kinase phosphorylation. In contrast, p38 MAPK and extracellular signal-regulated kinase (ERK) phosphorylation were inhibited by bakuchiol. In vivo experiments, Bakuchiol reduced microglial activation in the hippocampus and cortex tissue of LPS-injected mice. Bakuchiol significantly suppressed LPS-injected production of TNF-α and IL-6 in serum. These results indicate that the anti-neuroinflammatory effects of bakuchiol in activated microglia are mainly regulated by the inhibition of the p38 MAPK and ERK pathways. We suggest that bakuchiol may be beneficial for various neuroinflammatory diseases.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Qi Shang ◽  
Xiang Yu ◽  
Hui Ren ◽  
Gengyang Shen ◽  
Wenhua Zhao ◽  
...  

Extracts from plastrum testudinis (PTE) are active compounds that have been used to treat bone diseases in traditional Chinese medicine for thousands of years. In previous studies, we demonstrated their effects on glucocorticoid-induced osteoporosis both in vivo and in vitro. However, the mechanisms by which PTE regulates the osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (rBMSCs) in vitro remain poorly understood. In this study, rBMSCs were treated with medium (CON), PTE, osteogenic induction (OI), and a combination of PTE and OI (PTE+OI) over a 21-day period. We found that PTE significantly promoted rBMSCs osteogenic differentiation and mineralisation after 21 days of culturing. Moreover, PTE+OI further enhanced the differentiation and mineralisation process. PTE upregulated STE20, IGF1R, and p38 MAPK mRNA expression and downregulated TRAF6 mRNA expression. The extracts inhibited TRAF6 protein expression and promoted STE20, IGF1R, and phosphorylated p38 MAPK protein expression. Our results imply that PTE promotes the proliferation and osteogenic differentiation of rBMSCs by upregulating p38 MAPK, STE20, and IGF1R and downregulating TRAF6 expression, which may provide experimental evidence of the potential of PTE in the treatment of osteoporosis.


2000 ◽  
Vol 278 (4) ◽  
pp. C822-C833 ◽  
Author(s):  
Krystyna E. Rys-Sikora ◽  
Raymond L. Konger ◽  
John W. Schoggins ◽  
Rama Malaviya ◽  
Alice P. Pentland

PGE2 levels are altered in human epidermis after in vivo wounding; however, mechanisms modulating PGE2 production in activated keratinocytes are unclear. In previous studies, we showed that PGE2 is a growth-promoting autacoid in human primary keratinocyte cultures, and its production is modulated by plating density, suggesting that regulated PGE2 synthesis is an important component of wound healing. Here, we examine the role of phospholipase A2(PLA2) and cyclooxygenase (COX) enzymes in modulation of PGE2 production. We report that the increased PGE2 production that occurs in keratinocytes grown in nonconfluent conditions is also observed after in vitro wounding, indicating that similar mechanisms are involved. This increase was associated with coordinate upregulation of both COX-2 and secretory PLA2 (sPLA2) proteins. Increased sPLA2 activity was also observed. By RT-PCR, we identified the presence of type IIA and type V sPLA2, along with the M-type sPLA2 receptor. Thus the coordinate expression of sPLA2 and COX-2 may be responsible for the increased prostaglandin synthesis in activated keratinocytes during wound repair.


2022 ◽  
Vol 15 (1) ◽  
pp. 84
Author(s):  
Mario Abate ◽  
Cristina Pagano ◽  
Milena Masullo ◽  
Marianna Citro ◽  
Simona Pisanti ◽  
...  

The fruit of Garcinia mangostana (mangosteen) is known in ancient traditional Asian medicine for its antioxidant, anti-inflammatory, immunomodulatory and anticancer activities. These effects are mainly due to the action of polyphenols known as xanthones, which are contained in the pericarp of the fruit. In recent years, there has been a growing interest from pharmaceutical companies in formulating new topicals based on mangosteen full extracts to prevent skin aging. However, the molecules responsible for these effects and the mechanisms involved have not been investigated so far. Here, the arils and shells of Garcinia mangostana were extracted with chloroform and methanol, and the extracts were further purified to yield 12 xanthone derivatives. Their effects were evaluated using in vitro cultures of human epidermal keratinocytes. After confirming the absence of cytotoxicity, we evaluated the antioxidant potential of these compounds, identifying mangostanin as capable of both protecting and restoring oxidative damage induced by H2O2. We showed how mangostanin, by reducing the generation of intracellular reactive oxygen species (ROS), prevents the activation of AKT (protein kinase B), ERK (extracellular signal-regulated kinase), p53, and other cellular pathways underlying cell damage and apoptosis activation. In conclusion, our study is the first to demonstrate that mangostanin is effective in protecting the skin from the action of free radicals, thus preventing skin aging, confirming a potential toward its development in the nutraceutical and cosmeceutical fields.


Sign in / Sign up

Export Citation Format

Share Document