Background & Aims Obesity and metabolic syndrome have been associated with alterations to the intestinal microbiota. However, few studies examined the effects of obesity on the intestinal immune ...system. We investigated changes in subsets of intestinal CD4+ T-helper (TH ) cells with obesity and the effects of gut-tropic TH 17 cells in mice on a high-fat diet (HFD). Methods We isolated immune cells from small intestine and adipose tissue of C57BL/6 mice fed a normal chow diet or a HFD for 10 weeks and analyzed the cells by flow cytometry. Mice fed a vitamin A−deficient HFD were compared with mice fed a vitamin A−sufficient HFD. Obese RAG1-deficient mice were given injections of only T regulatory cells or a combination of T regulatory cells and TH 17 cells (wild type or deficient in integrin β7 subunit or interleukin 17 IL17). Mice were examined for weight gain, fat mass, fatty liver, glucose tolerance, and insulin resistance. Fecal samples were collected before and after T-cell transfer and analyzed for microbiota composition by metagenomic DNA sequencing and quantitative polymerase chain reaction. Results Mice placed on a HFD became obese, which affected the distribution of small intestinal CD4+ TH cells. Intestinal tissues from obese mice had significant reductions in the proportion of TH 17 cells but increased proportion of TH 1 cells, compared with intestinal tissues from nonobese mice. Depletion of vitamin A in obese mice further reduced the proportion of TH 17 cells in small intestine; this reduction correlated with more weight gain and worsening of glucose intolerance and insulin resistance. Adoptive transfer of in vitro−differentiated gut-tropic TH 17 cells to obese mice reduced these metabolic defects, which required the integrin β7 subunit and interleukin 17. Delivery of TH 17 cells to intestines of mice led to expansion of commensal microbes associated with leanness. Conclusions In mice, intestinal TH 17 cells contribute to development of a microbiota that maintains metabolic homeostasis, via interleukin 17. Gut-homing TH 17 cells might be used to reduce metabolic disorders in obese individuals.
Display omitted
As DYRK1A and 1B inhibitors, 1H-pyrazolo3,4-bpyridine derivatives were synthesized. Mostly, 3-aryl-5-arylamino compounds (6) and 3,5-diaryl compounds (8 and 9) were prepared and ...especially, 3,5-diaryl compound 8 and 9 showed excellent DYRK1B inhibitory enzymatic activities with IC50 Values of 3–287 nM. Among them, 3-(4-hydroxyphenyl), 5-(3,4-dihydroxyphenyl)-1H-pyrazolo3,4-bpyridine (8h) exhibited the highest inhibitory enzymatic activity (IC50 = 3 nM) and cell proliferation inhibitory activity (IC50 = 1.6 µM) towards HCT116 colon cancer cells. Also compound 8h has excellent inhibitory activities in patient-derived colon cancer organoids model as well as in 3D spheroid assay model of SW480 and SW620. The docking study supported that we confirmed that compound 8h binds to DYRK1B through various hydrogen bonding interactions and hydrophobic interactions.
Abstract
Tetraspanin family proteins form a rigid membrane structure called tetraspanin-enriched microdomain (TEM) on the plasma membrane and regulate multiple cellular processes. CD82, a tetraspanin ...protein, is highly expressed in various immune cells, but its role in immune responses has been poorly understood. In this study, we investigated the role of CD82 in T cells using CD82 knock-out (KO) mice. At steady state, CD82 KO mice had less memory CD8+ T cells in secondary lymphoid organs compared to wild type mice, which became more pronounced in aged mice. Upon in vitro T cell receptor (TCR) stimulation, CD82 KO CD8+ T cells showed defects in phosphorylation of TCR downstream signaling molecules, activation marker expression, proliferation, and cytokine production. By confocal immunofluorescence imaging, we found that TCR stimulation-induced translocation of the microtubule organizing center and formation of the immunological synapse was impaired in CD82 KO T cells. CD82 seems to recruit T cell polarity-regulating molecules such as Scribble via the PDZ domain-binding motif located in its C-terminus and mediate the T cell polarization. In association with the defective CD8+ T cell activation caused by CD82 deficiency, CD82 KO CD8+ T cells show less efficient anti-tumor immune responses than wild-type cells when transferred to tumor-bearing mice. Collectively, our study demonstrates that CD82 mediates the T cell polarization and is required for the optimal CD8+ T cell effector function.
Microwave‐assisted synthesis of 5,6,7‐trisubstitutedpyrrolo2,3‐d pyrimidines viapalladium‐catalyzed heteroannulation with internal alkynes AreumPark, Sung Min Choi, Tae Sung Kim, and Eul Kgun Yum.
Spodoptera frugiperda is a pest with a wide host range that causes severe damage to the agricultural sector around the world. The species, which was first recorded in South Korea in 2019, has been ...affecting corn farmers by harming the leaves and fruits. Unfortunately, measures to initially respond to the species have not been implemented appropriately due to the lack of information on the growth characteristics of S. frugiperda in the Korean climate. Against this backdrop, we analyzed the growth characteristics and degree of damage to corn leaves at different temperatures and found that the optimal temperature for the growth of S. frugiperda was in the range 28–32 °C, which is the temperature range during summer in Korea. It is most active during this season, affecting more number of farmers progressively. In this regard, more efforts are needed to control the pest in summer in Korea. In 2019, an outbreak of Spodoptera frugiperda (Smith) was first reported in Korea. This study aimed to determine the growth rate and feeding amount of S. frugiperda by temperature to establish the right time window for its control and management. Linear regression analysis was used to determine the growth period and thermal requirements of S. frugiperda. The longest growth period of 97.2 ± 1.2 days was observed at 16 °C, and the shortest growth period of 15.5 ± 0.7 days was observed at 36 °C. In terms of each growth stage, the pupal period was the longest at all temperatures, followed by the egg period. The maximum corn leaf feeding amount (6.61 g) was observed for the larvae grown at 16 °C, and the minimum (2.9 g) was observed at 36 °C. However, the daily feeding amount of S. frugiperda larvae was the highest at 28 °C and 32 °C. The hatching rate according to temperature exceeded 70% at 24 °C, 28 °C, and 32 °C, and the survival rate of larvae and pupae was 100% at 24 °C to 32 °C. Based on these results, a temperature range of 28 °C to 32 °C is proposed as the optimum temperature for the growth of S. frugiperda.
Redox-active metal ions are pivotal for rapid metabolism, proliferation, and aggression across cancer types, and this presents metal chelation as an attractive cancer cell-targeting strategy. Here, ...we identify a metal chelator, KS10076, as a potent anti-cancer drug candidate. A metal-bound KS10076 complex with redox potential for generating hydrogen peroxide and superoxide anions induces intracellular reactive oxygen species (ROS). The elevation of ROS by KS10076 promotes the destabilization of signal transducer and activator of transcription 3, removes aldehyde dehydrogenase isoform 1-positive cancer stem cells, and subsequently induces autophagic cell death. Bioinformatic analysis of KS10076 susceptibility in pan-cancer cells shows that KS10076 potentially targets cancer cells with increased mitochondrial function. Furthermore, patient-derived organoid models demonstrate that KS10076 efficiently represses cancer cells with active KRAS, and fluorouracil resistance, which suggests clinical advantages.
Display omitted
•Drug screening identifies a metal chelator, KS10076, with potent cytotoxicity•KS10076 destabilizes STAT3 by elevating ROS•ROS-mediated STAT3 degradation affects mitochondrial and lysosomal membrane disruption•KS10076 induces autophagic cell death and eliminates ALDH1+ cancer stem cells
Kim et al. report that a metal chelator, KS10076, increases intracellular ROS and degrades STAT3 in cancer cells. Elevation of ROS by KS10076 leads to organelle dysfunction and removes cancer stem cells, resulting in autophagic cancer cell death in both in vitro and in vivo models.
We previously identified KS40008 (4-(3-(4-hydroxyphenyl)-1H-pyrazolo3,4-bpyridin-5-yl)benzene-1,2-diol), a novel inhibitor of dual-specificity tyrosine phosphorylation-regulated kinase family (DYRK) ...1A/B, which exhibited high enzymatic activity and cell proliferation-inhibitory effects in colorectal cancer (CRC) cell lines. In the present study, we aimed to elucidate the antitumor mechanisms of KS40008.
To assess the cytotoxicity of KS40008, we utilized a human cell line and organoid model and performed a CCK-8 assay and real-time cell analysis. Mitochondrial function was determined through mitochondrial staining, mito-stress test, and glycolysis test. In addition, we investigated the mechanisms of cancer cell death induced by KS40008 through immunoblotting, real-time quantitative polymerase chain reaction, reactive oxygen species staining, and immunofluorescence staining.
KS40008 exhibited significant cytotoxicity in CRC and non-CRC cell lines, and organoid models compared to 5-fluorouracil, a conventional chemotherapeutic drug. Moreover, KS40008-induced inhibition of DYRK1A/B led to mitochondrial dysfunction and endoplasmic reticulum stress, promoting autophagic cancer cell death.
KS40008 exerts antitumor activity through the inhibition of DYRK1A/B. Here, we demonstrated a mechanism by which KS40008 affects endoplasmic reticulum stress-mediated autophagy through the induction of mitochondrial stress, leading to cytotoxicity in CRC.
Candida antarctica lipase B (CAL-B) exhibits remarkable enantioselectivity for various chiral sec-alcohols, and the enantioselectivity is structurally well-understood. Two substituents at the chiral ...center of a sec-alcohol separately bind two pockets, namely, large and medium binding pockets. It has been believed that the medium pocket is too small to accommodate a large substituent (larger than an ethyl group), and thus, bulky sec-alcohols bearing two large substituents have been regarded as a poor substrate for CAL-B. However, we found that CAL-B can catalyze the transesterification of N-Boc-protected rac-2-amino-1-phenylethanol (1a) enantioselectively with a moderate reaction rate. X-ray crystallography and computer modeling revealed that the rotation of the Leu278 side chain creates a space to accept the N-Boc-aminomethylene group of 1a. Moreover, a sec-alcohol substrate with less than one hydrogen atom at the γ-position from the hydroxyl group is required to achieve a moderate reaction rate. On the basis of this observation, we diversified bulky N-Boc-protected rac-2-amino-1-arylethanols for the transesterifications with high enantioselectivities (E > 200).
The transcription of inflammatory genes is an essential step in host defense activation. Here, we show that cellular nucleic acid-binding protein (CNBP) acts as a transcription regulator that is ...required for activating the innate immune response. We identified specific CNBP-binding motifs present in the promoter region of sustained inflammatory cytokines, thus, directly inducing the expression of target genes. In particular, lipopolysaccharide (LPS) induced cnbp expression through an NF-κB-dependent manner and a positive autoregulatory mechanism, which enables prolonged il-6 gene expression. This event depends strictly on LPS-induced CNBP nuclear translocation through phosphorylation-mediated dimerization. Consequently, cnbp-depleted zebrafish are highly susceptible to Shigella flexneri infection in vivo. Collectively, these observations identify CNBP as a key transcriptional regulator required for activating and maintaining the immune response.
PDF
