Protective Effect of Fermented Sea Tangle Extract on Skin Cell Damage Caused by Particulate Matter.

The skin is directly exposed to atmospheric pollutants, especially particulate matter 2.5 (PM2.5) in the air, which poses significant harm to skin health. However, limited research has been performed to identify molecules that can confer resistance to such substances. Herein, we analyzed the effect of fermented sea tangle (FST) extract on PM2.5-induced human HaCaT keratinocyte damage. Results showed that FST extract, at concentrations less than 800 µg/mL, exhibited non-significant toxicity to cells and concentration-dependent inhibition of PM2.5-induced reactive oxygen species (ROS) production. PM2.5 induced oxidative stress by stimulating ROS, resulting in DNA damage, lipid peroxidation, and protein carbonylation, which were inhibited by the FST extract. FST extract significantly suppressed the increase in calcium level and apoptosis caused by PM2.5 treatment and significantly restored the reduced cell viability. Mitochondrial membrane depolarization occurred due to PM2.5 treatment, however, FST extract recovered mitochondrial membrane polarization. PM2.5 inhibited the expression of the anti-apoptotic protein Bcl-2, and induced the expression of pro-apoptotic proteins Bax and Bim, the apoptosis initiator caspase-9, as well as the executor caspase-3, however, FST extract effectively protected the changes in the levels of these proteins caused by PM2.5. Interestingly, pan-caspase inhibitor Z-VAD-FMK treatment enhanced the anti-apoptotic effect of FST extract in PM2.5-treated cells. Our results indicate that FST extract prevents PM2.5-induced cell damage via inhibition of mitochondria-mediated apoptosis in human keratinocytes. Accordingly, FST extract could be included in skin care products to protect cells against the harmful effects of PM2.5.

Intermittent Fasting Modulates Immune Response by Generating Tregs via TGF-ß Dependent Mechanisms in Obese Mice with Allergic Contact Dermatitis.

People with obesity maintain low levels of inflammation; therefore, their exposure to foreign antigens can trigger an excessive immune response. In people with obesity or allergic contact dermatitis (ACD), symptoms are exacerbated by a reduction in the number of regulatory T cells (Tregs) and IL-10/TGF-ß-modified macrophages (M2 macrophages) at the inflammatory site. Benefits of intermittent fasting (IF) have been demonstrated for many diseases; however, the immune responses regulated by macrophages and CD4+T cells in obese ACD animal models are poorly understood. Therefore, we investigated whether IF suppresses inflammatory responses and upregulates the generation of Tregs and M2 macrophages in experimental ACD animal models of obese mice. The IF regimen relieved various ACD symptoms in inflamed and adipose tissues. We showed that the IF regimen upregulates Treg generation in a TGF-ß-dependent manner and induces CD4+T cell hypo-responsiveness. IF-M2 macrophages, which strongly express TGF-ß and inhibit CD4+T cell proliferation, directly regulated Treg differentiation from CD4+T cells. These results indicate that the IF regimen enhances the TGF-ß-producing ability of M2 macrophages and that the development of Tregs keeps mice healthy against ACD exacerbated by obesity. Therefore, the IF regimen may ameliorate inflammatory immune disorders caused by obesity.

Diesel exhaust particulate matter impairs Toll-like receptor signaling and host defense against staphylococcal cutaneous infection in mice.

Air pollution is an emerging cause of mortality, affecting nearly 5 million people each year. Exposure to diesel exhaust fine particulate matter (PM2.5) aggravates respiratory and skin conditions. However, its impact on the protective immunity of the skin remains poorly understood. This study aimed to investigate the underlying molecular mechanism for adverse effects of PM2.5 on the host protective immunity using in vitro cell and in vivo mouse model. Intracellular translocation of Toll-like receptor 9 (TLR9) and CpG-DNA internalization were assessed in dendritic cells without or with PM2.5 treatment using immunofluorescence staining. Cytokine and nitric oxide production were measured in dendritic cells and macrophages without or with PM2.5 treatment. NF-κB and MAPK signaling was determined using western blotting. Skin disease severity, bacterial loads, and cytokine production were assessed in cutaneous Staphylococcus aureus (S. aureus) infection mouse model. PM2.5 interfered with TLR9 activation by inhibiting both TLR9 trafficking to early endosomes and CpG-DNA internalization via clathrin-mediated endocytosis. In addition, exposure to PM2.5 inhibited various TLR-mediated nitric oxide and cytokine production as well as MAPK and NF-κB signaling. PM2.5 rendered mice more susceptible to staphylococcal skin infections. Our results suggest that exposure to PM impairs TLR signaling and dampens the host defense against staphylococcal skin infections. Our data provide a novel perspective into the impact of PM on protective immunity which is paramount to revealing air pollutant-mediated toxicity on the host immunity.

Limonin, a Component of Immature Citrus Fruits, Activates Anagen Signaling in Dermal Papilla Cells.

Hair loss remains a significant problem that is difficult to treat; therefore, there is a need to identify safe natural materials that can help patients with hair loss. We evaluated the hair anagen activation effects of limonin, which is abundant in immature citrus fruits. Limonin increased the proliferation of rat dermal papilla cells (rDPC) by changing the levels of cyclin D1 and p27, and increasing the number of BrdU-positive cells. Limonin increased autophagy by decreasing phosphorylated mammalian target of rapamycin levels and increasing the phospho-Raptor, ATG7 and LC3B. Limonin also activated the Wnt/ß-catenin pathway by increasing phospho-ß-catenin levels. XAV939, a Wnt/ß-catenin inhibitor, inhibited these limonin-induced changes, including induced autophagy, BrdU-positive cells, and cell proliferation. Limonin increased the phosphorylated AKT levels in both two-dimensional cultured rDPC and three-dimensional spheroids. Treatment with the PI3K inhibitor wortmannin inhibited limonin-induced proliferation, and disrupted other limonin-mediated changes, including decreased p27, increased BrdU-positive cells, induced autophagy, and increased ATG7 and LC3B levels. Wortmannin also inhibited limonin-induced cyclin D1 and LC3 expression in spheroids. Collectively, these results indicate that limonin can enhance anagen signaling by activating autophagy via targeting the Wnt/ß-catenin and/or PI3K/AKT pathways in rDPC, highlighting a candidate nutrient for hair loss treatment.

Lycosin-II Exhibits Antifungal Activity and Inhibits Dual-Species Biofilm by Candida albicans and Staphylococcus aureus.

The increase and dissemination of antimicrobial resistance is a global public health issue. To address this, new antimicrobial agents have been developed. Antimicrobial peptides (AMPs) exhibit a wide range of antimicrobial activities against pathogens, including bacteria and fungi. Lycosin-II, isolated from the venom of the spider Lycosa singoriensis, has shown antibacterial activity by disrupting membranes. However, the mode of action of Lycosin-II and its antifungal activity have not been clearly described. Therefore, we confirmed that Lycosin-II showed antifungal activity against Candida albicans (C. albicans). To investigate the mode of action, membrane-related assays were performed, including an evaluation of C. albicans membrane depolarization and membrane integrity after exposure to Lycosin-II. Our results indicated that Lycosin-II damaged the C. albicans membrane. Additionally, Lycosin-II induced oxidative stress through the generation of reactive oxygen species (ROS) in C. albicans. Moreover, Lycosin-II exhibited an inhibitory effect on dual-species biofilm formation by C. albicans and Staphylococcus aureus (S. aureus), which are the most co-isolated fungi and bacteria. These results revealed that Lycosin-II can be utilized against C. albicans and dual-species strain infections.

Hesperidin Exhibits Protective Effects against PM2.5-Mediated Mitochondrial Damage, Cell Cycle Arrest, and Cellular Senescence in Human HaCaT Keratinocytes.

Particulate matter 2.5 (PM2.5) exposure can trigger adverse health outcomes in the human skin, such as skin aging, wrinkles, pigment spots, and atopic dermatitis. PM2.5 is associated with mitochondrial damage and the generation of reactive oxygen species (ROS). Hesperidin is a bioflavonoid that exhibits antioxidant and anti-inflammatory properties. This study aimed to determine the mechanism underlying the protective effect of hesperidin on human HaCaT keratinocytes against PM2.5-induced mitochondrial damage, cell cycle arrest, and cellular senescence. Human HaCaT keratinocytes were pre-treated with hesperidin and then treated with PM2.5. Hesperidin attenuated PM2.5-induced mitochondrial and DNA damage, G0/G1 cell cycle arrest, and SA-ßGal activity, the protein levels of cell cycle regulators, and matrix metalloproteinases (MMPs). Moreover, treatment with a specific c-Jun N-terminal kinase (JNK) inhibitor, SP600125, along with hesperidin markedly restored PM2.5-induced cell cycle arrest and cellular senescence. In addition, hesperidin significantly reduced the activation of MMPs, including MMP-1, MMP-2, and MMP-9, by inhibiting the activation of activator protein 1. In conclusion, hesperidin ameliorates PM2.5-induced mitochondrial damage, cell cycle arrest, and cellular senescence in human HaCaT keratinocytes via the ROS/JNK pathway.

Hesperidin Protects Human HaCaT Keratinocytes from Particulate Matter 2.5-Induced Apoptosis via the Inhibition of Oxidative Stress and Autophagy.

Numerous epidemiological studies have reported that particulate matter 2.5 (PM2.5) causes skin aging and skin inflammation and impairs skin homeostasis. Hesperidin, a bioflavonoid that is abundant in citrus species, reportedly has anti-inflammatory properties. In this study, we evaluated the cytoprotective effect of hesperidin against PM2.5-mediated damage in a human skin cell line (HaCaT). Hesperidin reduced PM2.5-induced intracellular reactive oxygen species (ROS) generation and oxidative cellular/organelle damage. PM2.5 increased the proportion of acridine orange-positive cells, levels of autophagy-related proteins, beclin-1 and microtubule-associated protein light chain 3, and apoptosis-related proteins, B-cell lymphoma-2-associated X protein, cleaved caspase-3, and cleaved caspase-9. However, hesperidin ameliorated PM2.5-induced autophagy and apoptosis. PM2.5 promoted cellular apoptosis via mitogen-activated protein kinase (MAPK) activation by promoting the phosphorylation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38. The MAPK inhibitors U0126, SP600125, and SB203580 along with hesperidin exerted a protective effect against PM2.5-induced cellular apoptosis. Furthermore, hesperidin restored PM2.5-mediated reduction in cell viability via Akt activation; this was also confirmed using LY294002 (a phosphoinositide 3-kinase inhibitor). Overall, hesperidin shows therapeutic potential against PM2.5-induced skin damage by mitigating excessive ROS accumulation, autophagy, and apoptosis.

Bactericidal activities and action mechanism of the novel antimicrobial peptide Hylin a1 and its analog peptides against Acinetobacter baumannii infection.

We developed an antimicrobial peptide (AMP) as a candidate substance for replacing antibiotics. Previously, a novel 18-amino acid antimicrobial peptide Hylin a1 was isolated from an electro-stimulated arboreal South American frog Hypsiboas albopunctatus, and was found to demonstrate antimicrobial activity and cytotoxicity. In a recent study, the analog peptides were designed based on the parent peptide Hylin a1 to decrease toxicity and to maintain antimicrobial efficacy. The analog peptides were substituted with alanine and lysine, resulting in the formation of amphipathic α-helical structures in membrane-mimicking environments and in the induction of hydrophobic moments and net charges. Moreover, the analog peptides showed lower hemolytic effects and mammalian cell selectivity than Hylin a1. In particularly Hylin a1-11K and Hylin a1-15K exhibited broad-spectrum antimicrobial activity and anti-biofilm activity against carbapenem-resistant Acinetobacter baumannii. Permeability assays indicated that analog peptides eliminated bacteria by binding to lipopolysaccharide and by disrupting the bacterial membrane. Hylin a1-11K and Hylin a1-15K reduced inflammation by suppressing pro-inflammatory cytokines expression by A. baumannii infection and effectively ameliorated carbapenem-resistant A. baumannii infection in mice. Therefore, our results suggest that the analog peptide substituted with several residues based on Hylin a1 have antibacterial and anti-inflammatory activity, and may be effective in the treatment of carbapenem-resistant A. baumannii infection.

5-Bromo-3,4-dihydroxybenzaldehyde Promotes Hair Growth through Activation of Wnt/ß-Catenin and Autophagy Pathways and Inhibition of TGF-ß Pathways in Dermal Papilla Cells.

Various studies addressing the increasing problem of hair loss, using natural products with few side effects, have been conducted. 5-bromo-3,4-dihydroxybenzaldehyde (BDB) exhibited anti-inflammatory effects in mouse models of atopic dermatitis and inhibited UVB-induced oxidative stress in keratinocytes. Here, we investigated its stimulating effect and the underlying mechanism of action on hair growth using rat vibrissa follicles and dermal papilla cells (DPCs), required for the regulation of hair cycle and length. BDB increased the length of hair fibers in rat vibrissa follicles and the proliferation of DPCs, along with causing changes in the levels of cell cycle-related proteins. We investigated whether BDB could trigger anagen-activating signaling pathways, such as the Wnt/ß-catenin pathway and autophagy in DPCs. BDB induces activation of the Wnt/ß-catenin pathway through the phosphorylation of GSG3ß and ß-catenin. BDB increased the levels of autophagic vacuoles and autophagy regulatory proteins Atg7, Atg5, Atg16L, and LC3B. We also investigated whether BDB inhibits the TGF-ß pathway, which promotes transition to the catagen phase. BDB inhibited the phosphorylation of Smad2 induced by TGF-ß1. Thus, BDB can promote hair growth by modulating anagen signaling by activating Wnt/ß-catenin and autophagy pathways and inhibiting the TGF-ß pathway in DPCs.

PEP27-2, a Potent Antimicrobial Cell-Penetrating Peptide, Reduces Skin Abscess Formation during Staphylococcus aureus Infections in Mouse When Used in Combination with Antibiotics.

PEP27, a 27-amino acid (aa) peptide secreted by Streptococcus pneumoniae, is an autolytic peptide that functions as a major virulence factor. To develop a clinically applicable antimicrobial peptide (AMP), we designed PEP27 analogs with Trp substitutions to enhance its antimicrobial activity compared to that of PEP27. Particularly, PEP27-2 showed strong antimicrobial activity against a wide variety of bacteria, including multidrug-resistant (MDR) bacteria. It was found that the antimicrobial activity of PEP27-2 was increased by substituting Trp for the aa at the middle position of PEP27. We found that PEP27-2 acts as an effective cell-penetrating peptide in bacterial and mammalian cells. Here, we proved that subcutaneous infection with MDR Staphylococcus aureus induced skin lesions such as skeletal muscle damage, deep inflammation, and necrosis of the overlaying dermis in mice. Combination treatment with antibiotics revealed synergistic effects, remarkably reducing abscess size and improving the bacteria removal rate from the infection site. Moreover, PEP27-2-antibiotic combination treatment reduced inflammation, lowering levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), IL-6, inducible NO synthase (iNOS), and cyclooxygenase (COX-2) in skin abscess tissue. The results suggest that the PEP27-2 peptide is a promising therapeutic option for combating MDR bacterial strains by enhancing antibiotic penetration and protecting against MDR bacteria.

A Novel Antimicrobial Peptides From Pine Needles of Pinus densiflora Sieb. et Zucc. Against Foodborne Bacteria.

Pine needles are used in several East Asian countries as food or traditional medicine. It contains functional components that exhibit a wide spectrum of pharmacological effects such as antioxidant, antimicrobial, anti-diabetic, and anti-inflammatory activities. We determined and characterized the novel antimicrobial peptides (AMPs) isolated from Pinus densiflora Sieb. et Zucc. The four active pine-needle (PN) peptides showed antimicrobial activity against foodborne bacteria with minimum inhibitory concentration (MIC) values within the range of 8-128 µg/ml. PN peptides showed no detectable hemolytic activity or cytotoxicity at the antimicrobial concentrations. The N-terminal amino acid sequence of the PN5 was identified using Edman degradation and Antimicrobial Peptide Database (APD) homology analysis showed that it was not identical to any other plant peptide. This suggests that PN5 can serve as an alternative therapeutic agent to be used in the food industry.

A phage protein-derived antipathogenic peptide that targets type IV pilus assembly.

Phage-inspired antibacterial discovery is a new approach that recruits phages in search for antibacterials with new molecular targets, in that phages are the biological entities well adapted to hijack host bacterial physiology in favor of their own thrive. We previously observed that phage-mediated twitching motility inhibition was effective to control the acute infections caused by Pseudomonas aeruginosa and that the motility inhibition was attributed to the delocalization of PilB, the type IV pilus (TFP) assembly ATPase by binding of the 136-amino acid (aa) phage protein, Tip. Here, we created a series of truncated and point-mutant Tip proteins to identify the critical residues in the Tip bioactivity: N-terminal 80-aa residues were dispensable for the Tip activity; we identified that Asp82, Leu84, and Arg85 are crucial in the Tip function. Furthermore, a synthetic 15-aa peptide (P1) that corresponds to Leu73 to Ala87 is shown to suffice for PilB delocalization, twitching inhibition, and virulence attenuation upon exogenous administration. The transgenic flies expressing the 15-aa peptide were resistant to P. aeruginosa infections as well. Taken together, this proof-of-concept study reveals a new antipathogenic peptide hit targeting bacterial motility and provides an insight into antibacterial discovery targeting TFP assembly.

ER71/ETV2 Promotes Hair Regeneration from Chemotherapeutic Drug-Induced Hair Loss by Enhancing Angiogenesis.

Chemotherapy-induced alopecia and hair loss can be stressful in patients with cancer. The hair grows back, but sometimes the hair tends to stay thin. Therefore, understanding mechanisms regulating hair regeneration may improve the management of chemotherapy-induced alopecia. Previous studies have revealed that chemotherapeutic agents induce a hair follicle vascular injury. As hair growth is associated with micro-vessel regeneration, we postulated that the stimulation of angiogenesis might enhance hair regeneration. In particular, mice treated with 5-fluorouracil (5-FU) showed delayed anagen initiation and reduced capillary density when compared with untreated controls, suggesting that the retardation of anagen initiation by 5-FU treatment may be attributed to the loss of perifollicular micro-vessels. We investigated whether the ETS transcription factor ETV2 (aka ER71), critical for vascular development and regeneration, can promote angiogenesis and hair regrowth in a 5-FU-induced alopecia mouse model. Tie2-Cre; Etv2 conditional knockout (CKO) mice, which lack Etv2 in endothelial cells, presented similar hair regrowth rates as the control mice after depilation. Following 5-FU treatment, Tie2-Cre; Etv2 CKO mice revealed a significant reduction in capillary density, anagen induction, and hair restoration when compared with controls. Mice receiving lentiviral Etv2 injection after 5-FU treatment showed significantly improved anagen induction and hair regrowth. Two-photon laser scanning microscopy revealed that enforced Etv2 expression restored normal vessel morphology after 5-FU mediated vessel injury. Our data suggest that vessel regeneration strategies may improve hair regrowth after chemotherapeutic treatment.

Myristoleic Acid Promotes Anagen Signaling by Autophagy through Activating Wnt/ß-Catenin and ERK Pathways in Dermal Papilla Cells.

Alopecia is a distressing condition caused by the dysregulation of anagen, catagen, and telogen in the hair cycle. Dermal papilla cells (DPCs) regulate the hair cycle and play important roles in hair growth and regeneration. Myristoleic acid (MA) increases Wnt reporter activity in DPCs. However, the action mechanisms of MA on the stimulation of anagen signaling in DPCs is not known. In this study, we evaluated the effects of MA on anagen-activating signaling pathways in DPCs. MA significantly increased DPC proliferation and stimulated the G2/M phase, accompanied by increasing cyclin A, Cdc2, and cyclin B1. To elucidate the mechanism by which MA promotes DPC proliferation, we evaluated the effect of MA on autophagy and intracellular pathways. MA induced autophagosome formation by decreasing the levels of the phospho-mammalian target of rapamycin (phospho-mTOR) and increasing autophagy-related 7 (Atg7) and microtubule-associated protein 1A/1B-light chain 3II (LC3II). MA also increased the phosphorylation levels of Wnt/ß-catenin proteins, such as GSK3ß (Ser9) and ß-catenin (Ser552 and Ser675). Treatment with XAV939, an inhibitor of the Wnt/ß-catenin pathway, attenuated the MA-induced increase in ß-catenin nuclear translocation. Moreover, XAV939 reduced MA-induced effects on cell cycle progression, autophagy, and DPC proliferation. On the other hand, MA increased the levels of phospho (Thr202/Tyr204)-extracellular signal regulated kinases (ERK). MA-induced ERK phosphorylation led to changes in the expression levels of Cdc2, Atg7 and LC3II, as well as DPC proliferation. Our results suggest that MA promotes anagen signaling via autophagy and cell cycle progression by activating the Wnt/ß-catenin and ERK pathways in DPCs.

Scorpion-Venom-Derived Antimicrobial Peptide Css54 Exerts Potent Antimicrobial Activity by Disrupting Bacterial Membrane of Zoonotic Bacteria.

Antibiotic resistance is an important issue affecting humans and livestock. Antimicrobial peptides are promising alternatives to antibiotics. In this study, the antimicrobial peptide Css54, isolated from the venom of C. suffuses, was found to exhibit antimicrobial activity against bacteria such as Listeria monocytogenes, Streptococcus suis, Campylobacter jejuni, and Salmonella typhimurium that cause zoonotic diseases. Moreover, the cytotoxicity and hemolytic activity of Css54 was lower than that of melittin isolated from bee venom. Circular dichroism assays showed that Css54 has an α-helix structure in an environment mimicking that of bacterial cell membranes. We examined the effect of Css54 on bacterial membranes using N-phenyl-1-naphthylamine, 3,3'-dipropylthiadicarbbocyanine iodides, SYTOX green, and propidium iodide. Our findings suggest that the Css54 peptide kills bacteria by disrupting the bacterial membrane. Moreover, Css54 exhibited antibiofilm activity against L. monocytogenes. Thus, Css54 may be useful as an alternative to antibiotics in humans and animal husbandry.

HNG, A Humanin Analogue, Promotes Hair Growth by Inhibiting Anagen-to-Catagen Transition.

The hair follicle goes through repetitive cycles including anagen, catagen, and telogen. The interaction of dermal papilla cells (DPCs) and keratinocytes regulates the hair cycle and hair growth. Humanin was discovered in the surviving brain cells of patients with Alzheimer's disease. HNG, a humanin analogue, activates cell growth, proliferation, and cell cycle progression, and it protects cells from apoptosis. This study was performed to investigate the promoting effect and action mechanisms of HNG on hair growth. HNG significantly increased DPC proliferation. HNG significantly increased hair shaft elongation in vibrissa hair follicle organ culture. In vivo experiment showed that HNG prolonged anagen duration and inhibited hair follicle cell apoptosis, indicating that HNG inhibited the transition from the anagen to catagen phase mice. Furthermore, HNG activated extracellular signal-regulated kinase (Erk)1/2, Akt, and signal transducer and activator of transcription (Stat3) within minutes and up-regulated vascular endothelial growth factor (VEGF) levels on DPCs. This means that HNG could induce the anagen phase longer by up-regulating VEGF, which is a Stat3 target gene and one of the anagen maintenance factors. HNG stimulated the anagen phase longer with VEGF up-regulation, and it prevented apoptosis by activating Erk1/2, Akt, and Stat3 signaling.

Vanillic Acid Stimulates Anagen Signaling via the PI3K/Akt/ ß-Catenin Pathway in Dermal Papilla Cells.

The hair cycle (anagen, catagen, and telogen) is regulated by the interaction between mesenchymal cells and epithelial cells in the hair follicles. The proliferation of dermal papilla cells (DPCs), mesenchymal-derived fibroblasts, has emerged as a target for the regulation of the hair cycle. Here, we show that vanillic acid, a phenolic acid from wheat bran, promotes the proliferation of DPCs via a PI3K/Akt/Wnt/ß-catenin dependent mechanism. Vanillic acid promoted the proliferation of DPCs, accompanied by increased levels of cell-cycle proteins cyclin D1, CDK6, and Cdc2 p34. Vanillic acid also increased the levels of phospho(ser473)- Akt, phospho(ser780)-pRB, and phospho(thr37/46)-4EBP1 in a time-dependent manner. Wortmannin, an inhibitor of the PI3K/ Akt pathway, attenuated the vanillic acid-mediated proliferation of DPCs. Vanillic acid-induced progression of the cell-cycle was also suppressed by wortmannin. Moreover, vanillic acid increased the levels of Wnt/ß-catenin proteins, such as phospho(ser9)- glycogen synthase kinase-3ß, phospho(ser552)-ß-catenin, and phospho(ser675)-ß-catenin. We found that vanillic acid increased the levels of cyclin D1 and Cox-2, which are target genes of ß-catenin, and these changes were inhibited by wortmannin. To investigate whether vanillic acid affects the downregulation of ß-catenin by dihydrotestosterone (DHT), implicated in the development of androgenetic alopecia, DPCs were stimulated with DHT in the presence and absence of vanillic acid for 24 h. Western blotting and confocal microscopy analyses showed that the decreased level of ß-catenin after the incubation with DHT was reversed by vanillic acid. These results suggest that vanillic acid could stimulate anagen and alleviate hair loss by activating the PI3K/Akt and Wnt/ß-catenin pathways in DPCs.

L-Ascorbic Acid Inhibits Breast Cancer Growth by Inducing IRE/JNK/CHOP-Related Endoplasmic Reticulum Stress-Mediated p62/SQSTM1 Accumulation in the Nucleus.

Anticancer effects of L-ascorbic acid (Vitamin C, L-AA) have been reported in various types of cancers. L-AA intake reduces breast cancer recurrence and mortality; however, the role of L-AA in the treatment of breast cancer remains poorly understood. In this study, we investigated the effect and mechanism action of L-AA on breast cancer growth. L-AA inhibited the growth of breast cancer cells by inducing apoptotic cell death at the evaluated treatment concentrations without affecting normal cells. Moreover, L-AA induces autophagosome formation via regulation of mammalian target of rapamycin (mTOR), Beclin1, and autophagy-related genes (ATGs) and increased autophagic flux. Notably, we observed that L-AA increased p62/SQSTM1 (sequestosome 1) protein levels. Accumulation of p62 protein in cancer cells in response to stress has been reported, but its role in cancer regulation remains controversial. Here, we demonstrated that L-AA-induced p62 accumulation is related to L-AA-induced breast cancer growth inhibition. Furthermore, L-AA induced endoplasmic reticulum (ER) stress via the IRE-JNK-CHOP (inositol-requiring endonuclease-c-Jun N-terminal kinase-C/EBP homologous protein) signaling pathways, which increased the nuclear levels of p62/SQSTM1. These findings provide evidence that L-AA-induced ER stress could be crucial for p62 accumulation-dependent cell death, and L-AA can be useful in breast cancer treatment.

Inhibitory effect of particulate matter on toll-like receptor 9 stimulated dendritic cells by downregulating mitogen-activated protein kinase and NF-κB pathway.

Ambient particulate matter (PM) is associated with adverse health consequences. However, the influence of PM on the innate immune system is poorly understood. The aim of the present study was to examine the effect of diesel particulate matter 2.5 µm (PM2.5, SRM1650b) on dendritic cells. PM2.5 significantly reduced cytokine levels of interleukin (IL)-12 p40, IL-6 and TNF-α levels in CpG-DNA (TLR9 ligand)-stimulated dendritic cells. To determine the mechanisms underlying this observed inhibition induced by PM2.5, western blot analysis was conducted. PM2.5 was found to downregulate ERK1/2, JNK1/2, p38 MAPKs, and NF-κB pathways. PM2.5 exposure decreased TLR9-dependent NF-κB and activator protein (AP-1) reporter luciferase activities. Our findings demonstrate that PM2.5 reduced the production of cytokines which may be associated with inhibition of MAPK and NF-κB signaling pathway. Further, data suggest the immunosuppressive effect of PM2.5 on the innate immune cells may lead to serious damage to the host immune system.