The protection role of human growth hormone on skin cells following ultraviolet B exposure.

BACKGROUND: Ultraviolet-B (UVB) radiation is the leading environmental cause of skin damage and photoaging. The epidermis and dermis layers of the skin mainly absorb UVB. UVB stimulates apoptosis, cell cycle arrest, generation of reactive oxygen species, and degradation of collagen and elastin fibers. OBJECTIVE: This study investigated the potential of human growth hormone (hGH) in protecting the skin fibroblasts and keratinocytes (HFFF-2 and HaCaT cell lines) from UVB-induced damage. METHODS: The MTT assay was performed to evaluate UVB-induced mitochondrial damage via assessing the mitochondrial dehydrogenase activity, and flow cytometry was carried out to investigate the effects of UVB and hGH on the cell cycle and apoptosis of UVB-irradiated cells. In addition, the fold change mRNA expression levels of Type I collagen and elastin in HFFF-2 cells were evaluated using the qRT-PCR method following UVB exposure. RESULTS: We observed that treatment of cells with hGH before UVB exposure inhibited UVB-induced loss of mitochondrial dehydrogenase activity, apoptosis, and sub-G1 population formation in both cell lines. We also found that hGH-treated HFFF-2 cells showed up-regulated mRNA expression of Type I collagen, elastin, and IGF-1 in response to UVB irradiation. CONCLUSION: These findings suggest hGH as a potential anti-UVB compound that can protect skin cells from UVB-induced damage. Our findings merit further investigation and can be used to better understand the role of hGH in skin photoaging.

Mechanistic studies on protective effects of total flavonoids from Ilex latifolia Thunb. on UVB-radiated human keratinocyte cell line (HaCaT cells) based on network pharmacology and molecular docking technique.

The aim of the present research is to investigate anti-UVB radiation activity of total flavonoids from Ilex latifolia Thunb. (namely large-leaved Kuding tea) on human keratinocyte cell line (HaCaT cells) based on network pharmacology and molecular docking technique. Network pharmacology was used to screen target genes of active ingredients from Ilex latifolia Thunb. associated with UVB irradiation. The possible signaling pathways were analyzed by KEGG enrichment and verified by cellular experiments. Molecular docking was used to assess the affinity between the active ingredients and the core targets. The prediction of network pharmacology and molecular docking was identified by series experiment in UVB-irradiated HaCaT cells. Network pharmacology results showed that the active ingredients of Ilex latifolia Thunb. for anti-UVB irradiation were mainly flavonoids, and the possible signaling pathways were involved in PI3K-AKT, apoptosis, MAPKs, NF-κB, and JAK-STAT3. Molecular docking indicated key binding activity between AKT1-Glycitein, STAT3-Formononetin, CASP3-Formononetin, TNF-Kaempferol, CASP3-Luteolin, and AKT1-Quercetin. The total flavonoid pretreatment (0.25-1.0 mg/mL) down-regulated the expression of IL-6, IL-1ß, and TNF-α in the cells determined by ELISA. The expression of phosphor PI3K, phosphor AKT, phosphor JAK, phosphor STAT3, phosphor JNK, and phosphor p38 MAPKs and COX-2 proteins in cytosolic and NF-κB p65 protein in nucleus were down-regulated and determined by western blot. It also protected UVB-irradiated cells from apoptosis by reducing apoptosis rate and down-regulating active-caspase 3. In a word, the total flavonoid treatment protected HaCaT cells from UVB injuries effectively, and the potential mechanism involves PI3K-AKT, JAK-STAT3, MAPK, and NF-κB pathway by anti-inflammatory and apoptosis action in cells. The mechanism in vivo experiment needs to be further confirmed in future.

Isolation, characterization and anti-UVB irradiation activity of an extracellular polysaccharide produced by Lacticaseibacillus rhamnosus VHPriobi O17.

The purpose of this study was to isolate exopolysaccharides (EPS) from lactic acid bacteria (LAB) and evaluate EPS anti-UVB viability. Lacticaseibacillus rhamnosus VHPriobi O17 with high EPS production was screened from 34 strains of LAB. The EPS (OP-2) produced by L. rhamnosus VHPriobi O17 was purified by alcohol precipitation and DEAE-µSphere anion exchange chromatography. By ion chromatography, FT-IR spectrum and gel column chromatography, EPS (OP-2) was a novel Man-like polysaccharide with the weight-averaged molecular of 84.2 kDa. The EPS (OP-2) can effectively alleviate HaCaT cells apoptosis and overproduction of reactive oxygen species (ROS) induced by UVB. The results also showed that it inhibited the release of pro-inflammatory cytokines (IL-1α, IL-6 and IL-8); and suppressed the phosphorylation cascade of JNK and p38 MAPK to reduce the expression level of active-caspase3, ultimately prevented cell apoptosis. Thus, the EPS produced by L. rhamnosus VHPriobi O17 have the potential to be used for human anti-UVB irradiation.

Purification, structural characterization and anti-UVB irradiation activity of an extracellular polysaccharide from Pantoea agglomerans.

Extracellular polysaccharide (EPS) produced by Pantoea agglomerans was purified for structural analysis and anti-UVB activity evaluation. The results showed that the EPS comprised of mannose and glucose in a ratio of 3:2. The molecular weight of EPS was estimated as 679 KDa. Fourier transform infrared spectrometry (FT-IR) showed that the EPS was composed of d-furanose without any substituent group. The structure of the EPS could be deduced as a repeated pentasaccharide arranged of three mannose molecules and two glucose molecules according to electrospray ionization mass spectrometry (ESI-MS) analysis and results mentioned above. The results also showed that the EPS attenuated UVB-induced cytotoxicity which was verified by morphology feature assay, down-regulated the expression of phosphor-JNK and active caspase3 significantly through MAPK pathway in UVB-irradiated HaCaT cells, and therefore protected the cells from apoptosis which could be identified by the lower apoptosis rate at low dose of UVB ray. In conclusion, the EPS as a macromolecule arranged by repeated pentasaccharide could protect HaCaT keratinocytes from UVB irradiation injury effectively, and the underlying mechanism may involve MAPK signaling pathway which contribute to apoptotic cell death. However, further studies on efficacy of the EPS in vivo are needed to determine.

Potential TSPO Ligand and Photooxidation Quencher Isorenieratene from Arctic Ocean Rhodococcus sp. B7740.

Due to its special aromatic structure, isorenieratene is thought to be an active natural antioxidant and photo/UV damage inhibitor. In this work, isorenieratene that was extracted from Rhodococcus sp. B7740 isolated from the Arctic Ocean, showed excellent scavenging ability of both singlet oxygen and hydroxyl radical in the UVB-induced auto-oxidation process using the EPR method. Within an ARPE-19 cell model damaged by UVB radiation, isorenieratene showed fine protective effects (1.13 ± 0.03 fold) compared with macular xanthophylls (MXs) through upregulating of tspo. The molecular docking was firstly performed to investigate the interaction of isorenieratene with TSPO as a special ligand. Results showed isorenieratene might form a better binding conformation (S-score -8.5438) than MXs and indicate that isorenieratene not only can function as a direct antioxidant but also activate tspo in ARPE-19 cells. Thus, isorenieratene might ease the UV-related damages including age-related macular degeneration (AMD).

Topical Use of Quercetin-Loaded Chitosan Nanoparticles Against Ultraviolet B Radiation.

Ultraviolet radiation is a major risk factor for human skin damage, especially solar ultraviolet-B (UVB) which can induce inflammation, photoaging, and skin cancer. Quercetin (Qu), one of flavonoid family members, has showed protective effects against UVB radiation. However, its application for topical use is limited by low hydrophilicity and poor percutaneous absorption. Herein, we found that Qu, if entrapped into TPP-Chitosan nanoparticles (TCs), can be efficiently uptake by HaCaT cells and easily permeate through the epidermis layer, meanwhile display better stability and low cytotoxicity. We also found that Qu-loaded TCs (QTCs) could notably enhance the effect of Qu on inhibiting the NF-kB/COX-2 signaling pathway as well as ameliorating the skin edema caused by UVB radiation. Therefore, this study provided a method to get rid of Qu's low hydrophilicity, enhance its percutaneous absorption and retention in the skin, and further improve its anti-UVB effect, and demonstrated that Qu-loaded chitosan nanoparticles can be used as the therapeutic agent for topical use against UVB radiation.

Quercetin deformable liposome: preparation and efficacy against ultraviolet B induced skin damages in vitro and in vivo.

Ultraviolet (UV) radiation has deleterious effects on cells through direct damage to DNA or through increasing generation of reactive oxygen species (ROS). The flavonol quercetin (Qu) provides cellular protection against UV radiation and the current investigation was carried out to develop a deformable liposome formulation of Qu to enhance its delivery into human skin and to improve its anti-UVB effect. The influence of surfactants (including Span 20, Tween 80 and sodium cholate) on the properties of Qu deformable liposomes was investigated. Liposomes composed of Qu, phosphatidylcholine (PC), cholesterol (Chol), and Tween 80 showed high entrapment efficiencies (80.41±4.22%), small particle sizes (132±14nm), high elasticity (10.48±0.71), and prolonged drug release. The cell viability in UVB-irradiated HaCaT cells increased to 89.89±4.5% at 24h and 78.8±3.19% at 48h following treatment with Qu defomable liposomes. The ROS and malondialdehyde (MDA) level were also reduced. The penetration rate was 3.8-fold greater than that of the Qu suspension. Moreover, the edema and inflammation was alleviated by Qu deformable liposomes. These results showed the potential of deformable liposomes to enhance the anti-UVB effects of Qu both in vitro and in vivo.