The Production IL-21 and VEGF in UVB-irradiated Human Keratinocyte Cell Line, HaCaT

Molecular Mapping of Hydrogen Sulfide Targets in Normal Human Keratinocytes

Although sulfur-rich thermal waters have ancestrally been used in the context of dermatological conditions, a global mapping of the molecular effects exerted by H2S on human keratinocytes is still lacking. To fill this knowledge gap, we subjected cultured human keratinocytes to distinct amounts of the non-gaseous hydrogen sulfur donor NaHS. We first checked that H2S accumulated in the cytoplasm of keratinocytes under our experimental conditions andused a combination of proteomics, genomics and biochemical approaches to unravel functionally relevant H2S targets in human keratinocytes. We found that the identified targets fall into two main categories: (i) the oxidative stress response molecules superoxide dismutase 2 (SOD2), NAD(P)H quinone dehydrogenase 1 (NQO1) and culin 3 (CUL3) and (ii) the chemokines interleukin-8 (IL-8) and CXCL2. Interestingly, NaHS also stimulated the caspase-1 inflammasome pathway, leading to increased secretion of the pro-inflammatory molecule interleukin-18 (IL-18). Interestingly, the secretion of interleukin-1 beta (IL-1β) was only modestly impacted by NaHS exposure despite a significant accumulation of IL-1β pro-form. Finally, we observed that NaHS significantly hampered the growth of human keratinocyte progenitors and stem cells cultured under clonogenic conditions or as epidermal cell sheets. We conclude that H2S exerts specific molecular effects on normal human keratinocytes.

Plasma cupping induces VEGF expression in skin cells through nitric oxide-mediated activation of hypoxia inducible factor 1

Despite a long history, the clinical efficacy of cupping therapy is still under debate. This is likely due to the lack of direct evidence for the biological actions of cupping, since the short exposure of cells to vacuum condition rarely has affects cellular activity. In this study, the medicinal properties of a recent medical technology, non-thermal plasma, were added to classical cupping and designated as 'plasma cupping' (PC). In our results, the plasma-generating efficacy was increased under a cupping-like semi-vacuum condition (410 Torr) rather than normal atmospheric pressure (760 Torr). Notably, while cupping rarely affects the angiogenic factor vascular-endothelial growth factor (VEGF)-A, the PC treatment on HaCaT human keratinocytes significantly induced the expression of VEGF-A. The increased expression of the VEGF-A gene after the PC treatment was expected to be a result of PC-mediated ERK protein activation. The PC-mediated activation of ERK was essential for the activity of hypoxia inducible factor (HIF) 1 alpha, which is responsible for the PC-mediated expression of VEGF-A. The PC mediated increase of NO in the media was thought as a main reason for the elevated HIF-1 protein activity. In addition to the angiogenesis-promoting action of PC, it also showed anti-inflammatory activity by reducing TNF-α-mediated IL-1β and IL-6 expression. Taken together, this study indicates the potential for PC that could enhance the clinical efficacy of cupping by adding the effects of non-thermal plasma to traditional cupping.

Upregulated Interleukin 21 Receptor Enhances Proliferation and Epithelial-Mesenchymal Transition Process in Benign Prostatic Hyperplasia

Background: Interleukins (ILs) and related chronic inflammation have been found to contribute to the development of benign prostatic hyperplasia (BPH) in recent decades. As a late member of the ILs family, IL-21 receptor (IL-21R) can modulate cell proliferation, however, IL-21R activity in the prostate has not been examined. The current study aimed to elucidate a potential role of IL-21R in the development of BPH. Material and Methods: Human prostate tissues, cell lines and rats were used. QRT-PCR, Western blot, and immunohistochemistry, along with hematoxylin and eosin, Masson's trichrome, and immunofluorescent staining were performed. BPH-1 cells with IL-21R silenced were cultured or co-cultured with macrophages (active THP-1, AcTHP-1). Apoptosis and cell cycle phases were determined via flow cytometry. Epithelial-mesenchymal transition (EMT) processes were also examined. In vivo, rat prostatitis was induced with intraprostatic injected lipopolysaccharide (LPS). Results: IL-21R was highly expressed in human as well as rat prostate, mainly in the epithelial compartment. BPH concomitant with prostatitis significantly upregulated the expression of IL-21R. Knockdown of IL-21R induced cell apoptosis and cycle arrest at G0/G1 phase, and blocked the EMT process in BPH-1 cells. When IL-21R silenced BPH-1 cells were co-cultured with AcTHP-1 cells, these aforementioned processes and IL-21R change were completely reversed. Prostatic hyperplasia was observed with IL-21R upregulated in LPS induced prostatitis rats. More specifically, the expression of apoptosis, cyclin, and EMT proteins in this rat model are altered in a manner consistent with that seen in the cell line model. Conclusions: Our novel data demonstrates the expression and functional activities of IL-21R in the mechanism for development of BPH. IL-21R mainly localized in prostate epithelium and it was upregulated in hyperplastic prostate tissues. IL-21R enhanced proliferation of BPH-1 cells, via inhibiting cell apoptosis, and modulating cell cycles, as well as the EMT process, in response to inflammatory stimuli.

Serum IL-21 levels are elevated in atopic dermatitis patients with acute skin lesions

BACKGROUND

Interleukin (IL)-21 is a member of the type I cytokine family and plays a role in the pathogenesis of T helper type 2 allergic diseases. It has been reported that IL-21 expression is upregulated in acute skin lesions in atopic dermatitis (AD) patients; however, little is known about the serum IL-21 levels of AD patients. The aim of this study was to quantify the serum IL-21 levels of AD patients and to evaluate the relationships between the serum IL-21 level and disease severity, laboratory markers, and eruption type in AD patients.

METHODS

We measured the serum IL-21 levels of adult AD patients and healthy control subjects using an enzyme-linked immunosorbent assay.

RESULTS

The adult AD patients exhibited significantly higher serum IL-21 levels than the healthy control subjects. A comparison of the patients' serum IL-21 levels based on the clinical severity of their AD revealed that the patients with severe AD demonstrated significantly higher serum IL-21 levels than those with mild AD and the healthy control subjects. The serum IL-21 levels were significantly correlated with the skin severity score, and especially with the degree of acute lesions such as erythema and edema/papules. The serum IL-21 level was not associated with laboratory markers, such as the serum IgE level, the serum thymus and activation-related chemokine level, blood eosinophilia, and the serum lactate dehydrogenase level.

CONCLUSIONS

These results suggest that IL-21 might be involved in the pathogenesis of AD, especially the development of acute skin lesions.

The role of ultraviolet radiation in the pathogenesis of pterygia (Review)

Pterygium is a common ophthalmic disease affecting humans only. Extensive epidemiological data have demonstrated a causative effect of chronic ultraviolet (UV) radiation on pterygia. Progress has been made in determining the origin of pterygia, their nasal predilection and wing‑shaped appearance, and the roles of UV radiation in the initiation and the development of pterygia. In the present review, the current understanding of the involvement of UV radiation in the pathogenesis of pterygia is summarized. This involvement includes the alteration of limbal stem cells and fibroblasts that contribute to the initiation of pterygia and the induction of various pro‑inflammatory cytokines, growth factors and matrix metalloproteinases that promote the progression of pterygia. Further elucidation of the roles of UV radiation in the pathogenesis of pterygia may help to encourage individuals at risk of developing pterygia to take preventive measures and aid researchers in the development of novel targeted therapeutic agents to treat pterygia.

The anti-inflammatory effect of alloferon on UVB-induced skin inflammation through the down-regulation of pro-inflammatory cytokines

UVB irradiation can induce biological changes in the skin, modulate immune responses and activate inflammatory reactions leading to skin damage. Alloferon, which is isolated from the blood of an experimentally infected insect, the blow fly Calliphora vicina, is known for its anti-viral and anti-tumor activities in mice model. However, the effect of alloferon against UVB irradiation and its specific mechanism are still unknown. In this study, we investigated the effect of alloferon on UVB-induced cutaneous inflammation in a human keratinocyte cell line, HaCaT. RPA and ELISA data showed that alloferon decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-1α, IL-1β, IL-6 and IL-18, both on the mRNA and protein level. Western blot analysis was done to determine if alloferon regulates the MAPK signaling pathway since the MAPK signaling pathway is activated by numerous inflammatory mediators and environmental stresses including UVB irradiation. Alloferon inhibited the activation of p38 mitogen-activated protein kinase (MAPK) induced by UVB irradiation. Furthermore, the topical application of alloferon on the UVB exposed skin of hairless mice showed that alloferon treatment significantly inhibited an increase in epithelial thickness in chronic UVB-irradiated mouse skin. These findings suggest that alloferon has significant anti-inflammatory effects not only on UVB-induced inflammation in the human keratinocyte cell line, HaCaT, but also on mouse skin.