Korea Research Institute of Bioscience and Biotechnology
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Longitudinal profiling of the blood transcriptome in an African green monkey aging model
African green monkeys (AGMs, Chlorocebus aethiops) are Old World monkeys which are used as experimental models in biomedical research. Recent technological advances in next generation sequencing are useful for unraveling the genetic mechanisms underlying senescence, aging, and age-related disease. To elucidate the normal aging mechanisms in older age, the blood transcriptomes of nine healthy, aged AGMs (15?23 years old), were analyzed over two years. We identified 910?1399 accumulated differentially expressed genes (DEGs) in each individual, which increased with age. Aging-related DEGs were sorted across the three time points. A major proportion of the aging-related DEGs belonged to gene ontology (GO) categories involved in translation and rRNA metabolic processes. Next, we sorted common aging-related DEGs across three time points over two years. Common aging-related DEGs belonged to GO categories involved in translation, cellular component biogenesis, rRNA metabolic processes, cellular component organization, biogenesis, and RNA metabolic processes. Furthermore, we identified 29 candidate aging genes that were upregulated across the time series analysis. These candidate aging genes were linked to protein synthesis. This study describes a changing gene expression pattern in AGMs during aging using longitudinal transcriptome sequencing. The candidate aging genes identified here may be potential targets for the treatment of aging.
Achieving similar root microbiota composition in neighbouring plants through airborne signalling
The ability to recognize and respond to environmental signals is essential for plants. In response to environmental changes, the status of a plant is transmitted to other plants in the form of signals such as volatiles. Root-associated bacteria trigger the release of plant volatile organic compounds (VOCs). However, the impact of VOCs on the rhizosphere microbial community of neighbouring plants is not well understood. Here, we investigated the effect of VOCs on the rhizosphere microbial community of tomato plants inoculated with a plant growth-promoting rhizobacterium Bacillus amyloliquefaciens strain GB03 and that of their neighbouring plants. Interestingly, high similarity (up to 69%) was detected in the rhizosphere microbial communities of the inoculated and neighbouring plants. Leaves of the tomato plant treated with strain GB03-released β-caryophyllene as a signature VOC, which elicited the release of a large amount of salicylic acid (SA) in the root exudates of a neighbouring tomato seedling. The exposure of tomato leaves to β-caryophyllene resulted in the secretion of SA from the root. Our results demonstrate for the first time that the composition of the rhizosphere microbiota in surrounding plants is synchronized through aerial signals from plants.
Structural interplays in the flexible N-terminus and scaffolding domain of human membrane protein caveolin 3
Caveolins are critical for the formation of caveolae, which are small invaginations of the plasma membrane involved in a variety of biological processes. Caveolin 3 (Cav3), one of three caveolin isoforms, is an integral membrane protein mainly expressed in muscle tissues. Although various human diseases associated with Cav3 have been reported, structural characterization of Cav3 in the membrane has not been investigated in enough depth to understand the structure?function relationship. Here, using solution NMR, we characterized membrane association, structural communications, and molecular dynamics of the monomeric Cav3 in detergent micelle environment, particularly focused on the whole N-terminal part that is composed of the flexible N-terminus and the scaffolding domain. The results revealed a complicated structural interplay of the individual segments composing the whole N-terminal part, including the pH-dependent helical region, signature motif-like region, signature motif, and scaffolding domain. Collectively, the present study provides novel structural insights into the whole N-terminal part of Cav3 that plays important biological roles in cellular processes and diseases. In particular, given that several disease-related mutations are located at the whole N-terminal part of Cav3, the sophisticated communications in the whole N-terminal segments are likely to have relevance to the molecular basis of Cav3-related disease
Tumour-derived Dilp8/INSL3 induces cancer anorexia by regulating feeding neuropeptides via Lgr3/8 in the brain
In patients with advanced-stage cancer, cancer-associated anorexia affects treatment success and patient survival. However, the underlying mechanism is poorly understood. Here, we show that Dilp8, a Drosophila homologue of mammalian insulin-like 3 peptide (INSL3), is secreted from tumour tissues and induces anorexia through the Lgr3 receptor in the brain. Activated Dilp8-Lgr3 signalling upregulated anorexigenic nucleobinding 1 (NUCB1) and downregulated orexigenic short neuropeptide F (sNPF) and NPF expression in the brain. In the cancer condition, the protein expression of Lgr3 and NUCB1 was significantly upregulated in neurons expressing sNPF and NPF. INSL3 levels were increased in tumour-implanted mice and INSL3-treated mouse hypothalamic cells showed Nucb2 upregulation and Npy downregulation. Food consumption was significantly reduced in intracerebrospinal INSL3-injected mice. In patients with pancreatic cancer, higher serum INSL3 levels increased anorexia. These results indicate that tumour-derived Dilp8/INSL3 induces cancer anorexia by regulating feeding hormones through the Lgr3/Lgr8 receptor in Drosophila and mammals.
Pheophorbide a derivatives exert antiwrinkle effects on UVB-induced skin aging in human fibroblasts
Pheophorbide a is a chlorophyll metabolic breakdown product. This study investigated the antiwrinkle effect of pheophorbide a (PA) and its derivatives, including pyropheophorbide a (PyroPA) and pyropheophorbide a methyl ester (PyroPA-ME), on ultraviolet (UV) B-stimulated CCD-986sk fibroblasts. PA, PyroPA, and PyroPA-ME effectively suppressed reactive oxygen species accumulation in UVB-exposed CCD-986sk fibroblasts. All three pheophorbides also reduced UVB-induced matrix metalloproteinase (MMP)-1 secretion and mRNA expression of MMP-1, MMP-2, and MMP-9. Treatment with pheophorbides resulted in increased procollagen synthesis, and this required enhancement of procollagen type I C-peptide content and mRNA expression of collagen type I alpha 1 (COL1A1) and COL1A2 in CCD-986sk cells. These antiwrinkle effects were more potent with PA and PyroPA than with PyroPA-ME. Furthermore, PA and PyroPA suppressed UVB-induced phosphorylation of extracellular signal-regulated protein kinase and c-Jun N-terminal kinase but not p38. Moreover, all three pheophorbides inhibited NF-κB p65 phosphorylation. Therefore, these pheophorbides, especially PA and PyroPA, can be used as antiwrinkle agents, and PA- or PyroPA-rich natural resources can be used in functional cosmetics.
A novel process for the coproduction of biojet fuel and high-value polyunsaturated fatty acid esters from heterotrophic microalgae Schizochytrium sp. ABC101
Herein we demonstrated an economically beneficial process coproducing biojet fuel and high-value polyunsaturated fatty acids (PUFAs) from Schizochytrium sp. ABC101 microalgae. Schizochytrium is a promising biofuel source for its rapid growth, high cell density, and fast lipid accumulation via heterotrophic cultivation. The most important feature of Schizochytrium is that half of its lipids are composed of omega-3 PUFAs (i.e., docosahexaenoic acid and docosapentaenoic acid), which are currently commercialized as dietary supplements at a high price. We observed direct injection of PUFA-rich lipid into a high-temperature catalytic reactor can cause rapid catalyst deactivation via coke deposition. Therefore, the PUFAs were separated by short-path distillation after transesterification. The remaining esters of saturated fatty acids (SFAs) were catalytically deoxygenated into C13?C18 n-paraffins, and then subsequently hydrocracked to produce iso-rich paraffins that are suitable as biojet fuel. As the result, 54.6 wt% PUFA-enriched esters (purity: 87.7%) and 20.4 wt% of qualified biojet fuel with respect to the initial lipids were obtained.
Novel 4-Oxoquinazoline-based N-Hydroxypropenamides as histone deacetylase inhibitors: design, synthesis, and biological evaluation
Two series of novel 4-oxoquinazoline-based N-hydroxypropenamides (9a-m and 10a-m) were designed, synthesized, and evaluated for their inhibitory and cytotoxicity activities against histone deacetylase (HDAC). The compounds showed good to potent HDAC inhibitory activity and cytotoxicity against three human cancer cell lines (SW620, colon; PC-3, prostate; NCI-H23, lung cancer). In this series, compounds with the N-hydroxypropenamide functionality impeded at position 7 on the 4-oxoquinazoline skeleton (10a-m) were generally more potent than compounds with the N-hydroxypropenamide moiety at position 6 (9a-m). Also, the N 3-benzyl-substituted derivatives (9h-m, 10h-m) exhibited stronger bioactivity than the N 3-alkyl-substituted ones (9a-e, 10a-e). Two compounds 10l and 10m were the most potent ones. Their HDAC inhibitory activity (IC50 values, 0.041-0.044 μM) and cytotoxicity (IC50 values, 0.671-1.211 μM) were approximately 2- to 3-fold more potent than suberoylanilide hydroxamic acid (SAHA). Some compounds showed up to 10-fold more potent HDAC6 inhibition compared to their inhibitory activity in total HDAC extract assay. Analysis of selected compounds 10l and 10m revealed that these compounds strongly induced both early and late apoptosis and arrested SW620 cells at the G2/M phase. Docking studies were carried out on the HDAC6 isoform for series 10a-m and revealed some important features contributing to the inhibitory activity of synthesized compounds.
Fargesin inhibits EGF-induced cell transformation and colon cancer cell growth by suppression of CDK2/cyclin E signaling pathway
Although the lignan compound fargesin is a major ingredient in Shin-Yi, the roles of fargesin in carcinogenesis and cancer cell growth have not been elucidated. In this study, we observed that fargesin inhibited cell proliferation and transformation by suppression of epidermal growth factor (EGF)-stimulated G1/S-phase cell cycle transition in premalignant JB6 Cl41 and HaCaT cells. Unexpectedly, we found that signaling pathway analyses showed different regulation patterns in which fargesin inhibited phosphatidylinositol 3-kinase/AKT signaling without an alteration of or increase in mitogen activated protein kinase (MAPK) in JB6 Cl41 and HaCaT cells, while both signaling pathways were abrogated by fargesin treatment in colon cancer cells. We further found that fargesin-induced colony growth inhibition of colon cancer cells was mediated by suppression of the cyclin dependent kinase 2 (CDK2)/cyclin E signaling axis by upregulation of p21WAF1/Cip1, resulting in G1-phase cell cycle accumulation in a dose-dependent manner. Simultaneously, the suppression of CDK2/cyclin E and induction of p21WAF1/Cip1 were correlated with Rb phosphorylation and c-Myc suppression. Taken together, we conclude that fargesin-mediated c-Myc suppression inhibits EGF-induced cell transformation and colon cancer cell colony growth by the suppression of retinoblastoma (Rb)-E2F and CDK/cyclin signaling pathways, which are mainly regulated by MAPK and PKB signaling pathways.
Extracellular vesicles from thapsigargin-treated mesenchymal stem cells ameliorated experimental colitis via enhanced immunomodulatory properties
Therapeutic applications of extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) have attracted considerable attention because of their immunomodulatory properties against immune-mediated, inflammatory diseases. Here, we demonstrated enhanced immunomodulatory properties of EVs secreted from endoplasmic reticulum (ER) stress inducer thapsigargin (TSG)-primed human Wharton’s jelly-derived MSCs (WJ-MSCs). EVs from TSG-primed WJ-MSCs (TSG-EV) showed increased yield and expression of immunomodulatory factors, such as transforming growth factor-β1 (TGFβ), cyclooxygenase-2 (COX2), and especially indoleamine 2,3-dioxygenase (IDO), compared to control EVs. TSG-EV showed a significantly enhanced immunosuppressive effect on human peripheral blood-derived T cell proliferation and Th1 and Th17 differentiation, whereas Treg and M2-type macrophage were enriched compared to a control EV-treated group. Furthermore, TSG-EV substantially mitigated mouse experimental colitis by reducing the inflammatory response and maintaining intestinal barrier integrity. A significant increase of Tregs and M2-type macrophages in colitic colons of a TSG-EV-treated mouse suggests an anti-inflammatory effect of TSG-EV in colitis model, possibly mediated by Treg and macrophage polarization. These data indicate that TSG treatment promoted immunomodulatory properties of EVs from WJ-MSCs, and TSG-EV may provide a new therapeutic approach for treatment of colitis.
Molecular evolution of dengue virus types 1 and 4 in Korean travelers
Dengue virus (DV) is a mosquito-borne virus that is endemic to many tropical and subtropical areas. Recently, the annual incidence of DV infection has increased worldwide, including in Korea, due to global warming and increased global travel. We therefore sought to characterize the molecular and evolutionary features of DV-1 and DV-4 isolated from Korean overseas travelers. We used phylogenetic analysis based on the full coding region to classify isolates of DV-1 in Korea into genotype I (43251, KP406802), genotype IV (KP406803), and genotype V (KP406801). In addition, we found that strains of DV-4 belonged to genotype I (KP406806) and genotype II (43257). Evidence of positive selection in DV-1 strains was identified in the C, prM, NS2A, and NS5 proteins, whereas DV-4 showed positive selection only in the non-structural proteins NS2A, NS3, and NS5. The substitution rates per site per year were 5.58 × 10-4 and 6.72 × 10-4 for DV-1 and DV-4, respectively, and the time of the most recent common ancestor was determined using the Bayesian skyline coalescent method. In this study, the molecular, phylogenetic, and evolutionary characteristics of Korean DV-1 and DV-4 isolates were evaluated for the first time.