The Effect of Lactobacillus plantarum Extracellular Vesicles from Korean Women in Their 20s on Skin Aging

Extracellular vesicles, which are highly conserved in most cells, contain biologically active substances. The vesicles and substances interact with cells and impact physiological mechanisms. The skin is the most external organ and is in direct contact with the external environment. Photoaging and skin damage are caused by extrinsic factors. The formation of wrinkles is a major indicator of skin aging and is caused by a decrease in collagen and hyaluronic acid. MMP-1 expression is also increased. Due to accruing damage, skin aging reduces the ability of the skin barrier, thereby lowering the skin’s ability to contain water and increasing the amount of water loss. L. plantarum suppresses various harmful bacteria by secreting an antimicrobial substance. L. plantarum is also found in the skin, and research on the interactions between the bacteria and the skin is in progress. Although several studies have investigated L. plantarum, there are only a limited number of studies on extracellular vesicles (EV) derived from L. plantarum, especially in relation to skin aging. Herein, we isolated EVs that were secreted from L. plantarum of women in their 20s (LpEVs). We then investigated the effect of LpEVs on skin aging in CCD986sk. We showed that LpEVs modulated the mRNA expression of ECM related genes in vitro. Furthermore, LpEVs suppressed wrinkle formation and pigmentation in clinical trials. These results demonstrated that LpEVs have a great effect on skin aging by regulating ECM related genes. In addition, our study offers important evidence on the depigmentation effect of LpEVs.     

Stimulatory Effects of Extracellular Vesicles Derived from Leuconostoc holzapfelii That Exists in Human Scalp on Hair Growth in Human Follicle Dermal Papilla Cells

Human hair follicle dermal papilla cells (HFDPCs) located in hair follicles (HFs) play a pivotal role in hair follicle morphogenesis, hair cycling, and hair growth. Over the past few decades, probiotic bacteria (PB) have been reported to have beneficial effects such as improved skin health, anti-obesity, and immuno-modulation for conditions including atopic dermatitis and inflammatory bowel disease (IBD). PB can secrete 50~150 nm sized extracellular vesicles (EVs) containing microbial DNA, miRNA, proteins, lipids, and cell wall components. These EVs can regulate communication between bacteria or between bacteria and their host. Although numerous biological effects of PB-EVs have been reported, the physiological roles of Leuconostoc holzapfelii (hs-Lh), which is isolated from human scalp tissue, and the extracellular vesicles derived from them (hs-LhEVs) are largely unknown. Herein, we investigated the effects of hs-LhEVs on hair growth in HFDPCs. We show that hs-LhEVs increase cell proliferation, migration, and regulate the cell cycle. Furthermore, hs-LhEVs were found to modulate the mRNA expression of hair-growth-related genes in vitro. These data demonstrate that hs-LhEVs can reduce apoptosis by modulating the cell cycle and promote hair growth by regulation via the Wnt/β-catenin signal transduction pathway.     

Wnt signaling in biliary development,proliferation, and fibrosis

Biliary fibrosis is an important pathological indicator of hepatobiliary damage. Cholangiocyte is the key cell type involved in this process. To reveal the pathogenesis of biliary fibrosis, it is essential to understand the normal development as well as the aberrant generation and proliferation of cholangiocytes. Numerous reports suggest that the Wnt signaling pathway is implicated in the physiological and pathological processes of cholangiocyte development and ductular reaction. In this review, we summarize the effects of Wnt pathway in cholangiocyte development from embryonic stem cells, as well as the underlying mechanisms of cholangiocyte responses to adult ductal damage. Wnt signaling pathway is regulated in a step-wise manner during each of the liver differentiation stages from embryonic stem cells to functional mature cholangiocytes. With the modulation of Wnt pathway, cholangiocytes can also be generated from adult liver progenitor cells and mature hepatocytes to repair liver damage. Non-canonical Wnt signaling is triggered in the active ductal cells during biliary fibrosis. Targeted control of the Wnt signaling may hold the great potential to reduce and/or reverse the biliary fibrogenic process.     

Syntenin-1-mediated small extracellular vesicles promotes cell growth,migration, and angiogenesis by increasing onco-miRNAs secretion in lung cancer cells

Small extracellular vesicles (sEVs) play a pivotal role in tumor progression by mediating intercellular communication in the tumor microenvironment (TME). Syntenin-1 induces malignant tumor progression in various types of human cancers, including human lung cancer and regulates biogenesis of sEVs. However, the function of syntenin-1-regulated sEVs and miRNAs in sEVs remains to be elucidated. In the present study, we aimed to demonstrate the role of oncogenic Ras/syntenin-1 axis in the release of sEVs and elucidate the function of syntenin-1-mediated miRNAs in sEVs in lung cancer progression. The results revealed that oncogenic Ras promoted the release of sEVs by inducing syntenin-1 expression; disruption of syntenin-1 expression impaired the release of sEVs as well as sEV-mediated cancer cell migration and angiogenesis. Moreover, we identified three miRNAs, namely miR-181a, miR-425-5p, and miR-494-3p, as onco-miRNAs loaded into syntenin-1-dependent sEVs. Remarkably, miR-494-3p was highly abundant in sEVs and its release was triggered by syntenin-1 expression and oncogenic Ras. Ectopic expression of the miR-494-3p mimic enhanced the migration and proliferation of lung cancer cells as well as tube formation in endothelial cells; however, the miR-494-3p inhibitor blocked sEV-mediated effects by targeting tyrosine-protein phosphatase nonreceptor type 12 (PTPN12), a tumor suppressor. sEVs promoted tumor growth and angiogenesis by downregulating PTPN12 expression; however, the miR-494-3p inhibitor significantly suppressed these effects in vivo, confirming that miR-494-3p acts as a major onco-miRNA loaded into lung cancer cell-derived sEVs. Eventually, the oncogenic Ras/syntenin-1 axis may induce cancer progression by increasing miR-494-3p loading into sEVs in lung cancer cells in the TME.Subject terms: Cancer microenvironment, Non-small-cell lung cancer, Oncogenesis     

Evaluation of Antimicrobial Properties of Lichen Substances against Plant Pathogens

Plant pathogens pose major threats on agriculture and horticulture, causing significant economic loss worldwide. Due to the continuous and excessive use of synthetic pesticides, emergence of pesticide resistant pathogens has become more frequent. Thus, there is a growing needs for environmentally-friendly and selective antimicrobial agents with a novel mode of action, which may be used in combination with conventional pesticides to delay development of pesticide resistance. In this study, we evaluated the potentials of lichen substances as novel biopesticides against eight bacterial and twelve fungal plant pathogens that have historically caused significant phytopathological problems in South Korea. Eight lichen substances of diverse chemical origins were extracted from axenic culture or dried specimen, and further purified for comparative analysis of their antimicrobial properties. Usnic acid and vulpinic acid exhibited strong antibacterial activities against Clavibacter michiganensis subsp. michiganensis. In addition, usnic acid and vulpinic acid were highly effective in the growth inhibition of fungal pathogens, such as Diaporthe eres, D. actinidiae, and Sclerotinia sclerotiorum. Intriguingly, the growth of Rhizoctonia solani was specifically inhibited by lecanoric acid, indicating that lichen substances exhibit some degrees of selectivity to plant pathogens. These results suggested that lichen substance can be used as a selective biopesticide for controlling plant disease of agricultural and horticultural significance, minimizing possible emergence of pesticide resistant pathogens in fields.     

Renal Cell Carcinoma-Infiltrating CD3low Vγ9Vδ1 T Cells Represent Potentially Novel Anti-Tumor Immune Players

Due to the highly immunogenic nature of renal cell carcinoma (RCC), the tumor microenvironment (TME) is enriched with various innate and adaptive immune subsets. In particular, gamma-delta (γδ) T cells can act as potent attractive mediators of adoptive cell transfer immunotherapy because of their unique properties such as non-reliance on major histocompatibility complex expression, their ability to infiltrate human tumors and recognize tumor antigens, relative insensitivity to immune checkpoint molecules, and broad tumor cytotoxicity. Therefore, it is now critical to better characterize human γδ T-cell subsets and their mechanisms in RCCs, especially the stage of differentiation. In this study, we aimed to identify γδ T cells that might have adaptive responses against RCC progression. We characterized γδ T cells in peripheral blood and tumor-infiltrating lymphocytes (TILs) in freshly resected tumor specimens from 20 RCC patients. Furthermore, we performed a gene set enrichment analysis on RNA-sequencing data from The Cancer Genome Atlas (TCGA) derived from normal kidneys and RCC tumors to ascertain the association between γδ T-cell infiltration and anti-cancer immune activity. Notably, RCC-infiltrating CD3^low Vγ9Vδ1 T cells with a terminally differentiated effector memory phenotype with up-regulated activation/exhaustion molecules were newly detected as predominant TILs, and the cytotoxic activity of these cells against RCC was confirmed in vitro. In an additional analysis of the TCGA RCC dataset, γδ T-cell enrichment scores correlated strongly with those for CTLs, Th1 cells, “exhausted” T cells, and M1 macrophages, suggesting active involvement of γδ T cells in anti-tumor rather than pro-tumor activity, and Vδ1 cells were more abundant than Vδ2 or Vδ3 cells in RCC tumor samples. Thus, we posit that Vγ9Vδ1 T cells may represent an excellent candidate for adoptive immunotherapy in RCC patients with a high risk of relapse after surgery.     

Effects of Radix Polygalae on Cognitive Decline and Depression in Estradiol Depletion Mouse Model of Menopause

Postmenopausal syndrome refers to symptoms caused by the gradual decrease in female hormones after mid-40 years. As a target organ of estrogen, decrease in estrogen causes various changes in brain function such as a decrease in choline acetyltransferase and brain-derived neurotrophic factor; thus, postmenopausal women experience cognitive decline and more depressive symptoms than age-matched men. Radix Polygalae has been used for memory boosting and as a mood stabilizer and its components have shown neuroprotective, antidepressant, and stress relief properties. In a mouse model of estrogen depletion induced by 4-vinylcyclohexene diepoxide, Radix Polygalae was orally administered for 3 weeks. In these animals, cognitive and depression-related behaviors and molecular changes related to these behaviors were measured in the prefrontal cortex and hippocampus. Radix Polygalae improved working memory and contextual memory and despair-related behaviors in 4-vinylcyclohexene diepoxide-treated mice without increasing serum estradiol levels in this model. In relation to these behaviors, choline acetyltransferase and brain-derived neurotrophic factor in the prefrontal cortex and hippocampus and bcl-2-associated athanogene expression increased in the hippocampus. These results implicate the possible benefit of Radix Polygalae in use as a supplement of estrogen to prevent conditions such as postmenopausal depression and cognitive decline.     

Caspase-cleaved TRAF1 negatively regulates the antiapoptotic signals of TRAF2 during TNF-induced cell death

Tumor necrosis factor (TNF) signaling leads to pleiotropic responses in a wide range of cell types, in part by activating antiapoptotic and proapoptotic pathways. Previous studies have suggested that TNF receptor-associated factor (TRAF) 2 can mediate crucial antiapoptotic signals during TNF stimulation. However, it is unclear how the antiapoptotic signals via TRAF2 in TNF-R1 signaling is regulated. Here we show that TRAF1 is cleaved by caspase-8 into two fragments during apoptosis induced by TNF. Overexpression of the C-terminal cleavage product, TRAF1-c, increased TNF-induced cell death of hybridoma T cells. Importantly, we demonstrate that the cleavage product of TRAF1 coimmunoprecipitates with TRAF2 that is released from the TNF-R1 complex in response to prolonged TNF treatment. These results indicate that caspase-dependent cleavage of TRAF1 generates TRAF1-c fragments that are able to bind TRAF2, and then sequester TRAF2 from the TNF-R1 complex, rendering cells, at least in part, sensitive to TNF.