Discovery of Terminal Oxazole-Bearing Natural Products by a Targeted Metabologenomic Approach

A targeted metabologenomic method was developed to selectively discover terminal oxazole-bearing natural products from bacteria. For this, genes encoding oxazole cyclase, a key enzyme in terminal oxazole biosynthesis, were chosen as the genomic signature to screen bacterial strains that may produce oxazole-bearing compounds. Sixteen strains were identified from the screening of a bacterial DNA library (1,000 strains) using oxazole cyclase gene-targeting polymerase chain reaction (PCR) primers. The PCR amplicon sequences were subjected to phylogenetic analysis and classified into nine clades. 1H-13C coupled-HSQC NMR spectra obtained from the culture extracts of the hit strains enabled the unequivocal detection of the target compounds, including five new oxazole compounds, based on the unique 1JCH values and chemical shifts of oxazole: lenzioxazole (1) possessing an unprecedented cyclopentane, permafroxazole (2) bearing a tetraene conjugated with carboxylic acid, tenebriazine (3) incorporating two modified amino acids, and methyl-oxazolomycins A and B (4 and 5). Tenebriazine displayed inhibitory activity against pathogenic fungi, whereas methyl-oxazolomycins A and B (4 and 5) selectively showed anti-proliferative activity against estrogen receptor-positive breast cancer cells. This metabologenomic method enables the logical and efficient discovery of new microbial natural products with a target structural motif without the need for isotopic labeling.

Discovery of a stilbenoid-flavanone hybrid as an antitumor Wnt/β-catenin signaling pathway inhibitor

A series of designed stilbenoid-flavanone hybrids featuring sp3-hybridized C2 and C3 atoms of C-ring was evaluated against colorectal cancers presented compounds 4, 17, and 20 as the most potential compounds among explored compounds. Evaluation of the anticancer activity spectrum of compounds 4, 17, and 20 against diverse solid tumors presented compounds 17 and 20 with interesting anticancer spectrum. The potencies of compounds 17 and 20 were assessed in comparison with FDA-approved anticancer drugs. Compound 17 was the, in general, the most potent showing low micromolar GI50 values that were more potent than the standard FDA-approved drugs against several solid tumors including colon, brain, skin, renal, prostate and breast tumors. Compound 17 was subjected for evaluation against normal cell lines and was subjected to a mechanism study in HCT116 colon cancer cells which presented it as an inhibitor of Wnt signaling pathway triggering G2/M cell cycle arrest though activation of p53-p21 pathway as well as intrinsic and extrinsic apoptotic death of colon cancer cells. Compound 17 might be a candidate for further development against diverse solid tumors including colon cancer.

Regional variations in retinopathy of prematurity incidence for preterm infants <32 weeks' gestation in China

OBJECTIVES

National-level data on the incidence of retinopathy of prematurity (ROP) in different regions of China is insufficient. This study aimed to compare ROP incidences and care practices in different regions of China and their relationship with regional gross domestic product (GDP) per capita.

STUDY DESIGN

Retrospective cohort study.

METHODS

All infants born at <32 weeks gestational age (GA) and admitted to 70 neonatal intensive care units (NICUs) from January 1, 2019, to December 31, 2020, were enrolled. Hospitals were categorised into three regional groups according to geographical locations and GDP per capita from high to low: Eastern, Central, and Western China. The incidence of death or ROP, and care practices were compared among the groups.

RESULTS

A total of 18,579 infants were enrolled. Median GA was 29.9 (interquartile range 28.4-31.0) weeks and birth weight was 1318.1 (317.2) g. The percentage of GA <28 weeks, complete administration of antenatal steroids, and weight gain velocity during NICU stay were highest in Eastern China and lowest in Western China (all P < 0.01). In Eastern, Central, and Western China, the rates of death or any stage of ROP were 33.3%, 38.5%, and 39.2%, respectively (P < 0.01).

CONCLUSIONS

There were considerable regional disparities in ROP incidence in preterm infants with GA <32 weeks in China. The incidence of death or ROP ranged from high to low in Western, Central, and Eastern China.

Antiproliferative Activity of Piceamycin by Regulating Alpha-Actinin-4 in Gemcitabine-Resistant Pancreatic Cancer Cells

Although gemcitabine-based regimens are widely used as an effective treatment for pancreatic cancer, acquired resistance to gemcitabine has become an increasingly common problem. Therefore, a novel therapeutic strategy to treat gemcitabine-resistant pancreatic cancer is urgently required. Piceamycin has been reported to exhibit antiproliferative activity against various cancer cells; however, its underlying molecular mechanism for anticancer activity in pancreatic cancer cells remains unexplored. Therefore, the present study evaluated the antiproliferation activity of piceamycin in a gemcitabine-resistant pancreatic cancer cell line and patient-derived pancreatic cancer organoids. Piceamycin effectively inhibited the proliferation and suppressed the expression of alpha-actinin-4, a gene that plays a pivotal role in tumorigenesis and metastasis of various cancers, in gemcitabine-resistant cells. Long-term exposure to piceamycin induced cell cycle arrest at the G0/G1 phase and caused apoptosis. Piceamycin also inhibited the invasion and migration of gemcitabine-resistant cells by modulating focal adhesion and epithelial-mesenchymal transition biomarkers. Moreover, the combination of piceamycin and gemcitabine exhibited a synergistic antiproliferative activity in gemcitabine-resistant cells. Piceamycin also effectively inhibited patient-derived pancreatic cancer organoid growth and induced apoptosis in the organoids. Taken together, these findings demonstrate that piceamycin may be an effective agent for overcoming gemcitabine resistance in pancreatic cancer.

Antiproliferative Activity of Gibbosic Acid H through Induction of G0/G1 Cell Cycle Arrest and Apoptosis in Human Lung Cancer Cells

Lung cancer is one of the most common causative cancers worldwide. Particularly, non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancer cases. NSCLC is a serious form of lung cancer that requires prompt diagnosis, and the 5-year survival rate for patients with this disease is only 24%. Gibbosic acid H (GaH), a natural lanostanoid obtained from the Ganoderma species (Ganodermataceae), has antiproliferative activities against colon and lung cancer cells. The aim of the present study was to evaluate the antiproliferative activity of GaH in NSCLC cells and to elucidate the underlying molecular mechanisms. GaH was found to induce G0/G1 cell cycle arrest and autophagy by activating adenosine monophosphate-activated protein kinase in A549 and H1299 cells. The induction of this cell cycle arrest was associated with the downregulation of cyclin E1 and CDK2. Additionally, the induction of autophagy by GaH was correlated with the upregulation of LC3B, beclin-1, and p53 expression. GaH also induced apoptosis by upregulating cleaved caspase-3 and Bax in the lung cancer cells. These findings suggest that GaH has a potential in the growth inhibition of human lung cancer cells.

Is the 'safe zone' identified in preoperative computed tomography helpful for choosing optimal implant for fixation of radial head fracture?

The purpose of this study is to assess the clinical significance of the radiologic safe zone based on computed tomography and to compare the outcomes of three different implants for fixation of isolated radial head fractures. We retrospectively reviewed 367 patients who underwent internal fixation for isolated radial head fractures. We newly defined two subtypes of Mason type II fractures associated with the radiographic safe zone (IIA, two-part fracture allowing for safe fixation of plate; IIB, two-part fracture not allowing for safe fixation). 170 patients (CCS group, n = 82; HCS group, n = 31; plate group, n = 57) were investigated with no significant differences in demographics. The range of pronation and supination at 1 month postoperatively (P = 0.04 and P = 0.04) and the range of supination at 6 and 12 months postoperatively (P = 0.03 and P = 0.03) were significantly smaller in the plate group. In Mason type IIB fractures, the average MEPS was higher in the CCS and HSC groups than in the plate group (P = 0.01 and P = 0.02). And the average DASH score was lower in the CCS and HCS groups (P < 0.01 and P < 0.01). Evaluation of the radiologic safe zone is potentially helpful in selecting better surgical fixation option. For type III fractures, 2.3-mm cortical screws would be a better option than Acutrak screws. Plates would not be suitable for type IIB radial head fractures.

Repurposing Synthetic Congeners of a Natural Product Aurone Unveils a Lead Antitumor Agent Inhibiting Folded P-Loop Conformation of MET Receptor Tyrosine Kinase

A library of 24 congeners of the natural product sulfuretin were evaluated against nine panels representing nine cancer diseases. While sulfuretin elicited very weak activities at 10 µM concentration, congener 1t was identified as a potential compound triggering growth inhibition of diverse cell lines. Mechanistic studies in HCT116 colon cancer cells revealed that congener 1t dose-dependently increased levels of cleaved-caspases 8 and 9 and cleaved-PARP, while it concentration-dependently decreased levels of CDK4, CDK6, Cdc25A, and Cyclin D and E resulting in induction of cell cycle arrest and apoptosis in colon cancer HCT116 cells. Mechanistic study also presented MET receptor tyrosine kinase as the molecular target mediating the anticancer activity of compound 1t in HCT116 cells. In silico study predicted folded p-loop conformation as the form of MET receptor tyrosine kinase responsible for binding of compound 1t. Together, the current study presents compound 1t as an interesting anticancer lead for further development.

Tandocyclinones A and B, Ether Bridged C-Glycosyl Benz[a]anthracenes from an Intertidal Zone Streptomyces sp

Two new proton-deficient metabolites, tandocyclinones A and B (1 and 2), were discovered via the chemical profiling of the Streptomyces sp. strain TDH03, which was isolated from a marine sediment sample collected from the intertidal mudflat in Tando Port, the Republic of Korea. The structures of 1 and 2 were elucidated as new ether-bridged C-glycosyl benz[a]anthracenes by using a combination of spectroscopic analyses of ultraviolet (UV) and mass spectrometry (MS) data, along with nuclear magnetic resonance (NMR) spectra, which were acquired in tetrahydrofuran (THF)-d8 selected after an extensive search for a solvent, resulting in mostly observable exchangeable protons in the 1H NMR spectrum. Their configurations were successfully assigned by applying a J-based configuration analysis, rotating-frame Overhauser enhancement spectroscopy (ROESY) NMR correlations, chemical derivatization methods based on NMR (a modified version of Mosher's method) and circular dichroism (CD) (Snatzke's method using Mo2(OAc)4-induced CD), as well as quantum-mechanics-based computational methods, to calculate the electronic circular dichroism (ECD). Tandocyclinones A and B (1 and 2) were found to have weak antifungal activity against Trichophyton mentagrophytes IFM40996 with an MIC value of 128 μg/mL (244 and 265 μM for 1 and 2, respectively). A further biological evaluation revealed that tandocyclinone A (1) displayed inhibitory activity against Mycobacterium avium (MIC50 = 40.8 μM) and antiproliferative activity against SNU638 and HCT116 cancer cells, with IC50 values of 31.9 µM and 49.4 µM, respectively.

Structure-Activity Relationship of Truncated 2,8-Disubstituted-Adenosine Derivatives as Dual A2A/A3 Adenosine Receptor Antagonists and Their Cancer Immunotherapeutic Activity

Based on hA2AAR structures, a hydrophobic C8-heteroaromatic ring in 5'-truncated adenosine analogues occupies the subpocket tightly, converting hA2AAR agonists into antagonists while maintaining affinity toward hA3AR. The final compounds of 2,8-disubstituted-N6-substituted 4'-thionucleosides, or 4'-oxo, were synthesized from d-mannose and d-erythrono-1,4-lactone, respectively, using a Pd-catalyst-controlled regioselective cross-coupling reaction. All tested compounds completely antagonized hA2AAR, including 5d with the highest affinity (Ki,A2A = 7.7 ± 0.5 nM). The hA2AAR-5d X-ray structure revealed that C8-heteroaromatic rings prevented receptor activation-associated conformational changes. However, the C8-substituted compounds still antagonized hA3AR. Structural SAR features and docking studies supported different binding modes at A2AAR and A3AR, elucidating pharmacophores for receptor activation and selectivity. Favorable pharmacokinetics were demonstrated, in which 5d displayed high oral absorption, moderate half-life, and bioavailability. Also, 5d significantly improved the antitumor effect of anti-PD-L1 in vivo. Overall, this study suggests that the novel dual A2AAR/A3AR nucleoside antagonists would be promising drug candidates for immune-oncology.

Targeted and Logical Discovery of Piperazic Acid-Bearing Natural Products Based on Genomic and Spectroscopic Signatures

A targeted and logical discovery method was devised for natural products containing piperazic acid (Piz), which is biosynthesized from ornithine by l-ornithine N-hydroxylase (KtzI) and N-N bond formation enzyme (KtzT). Genomic signature-based screening of a bacterial DNA library (2020 strains) using polymerase chain reaction (PCR) primers targeting ktzT identified 62 strains (3.1%). The PCR amplicons of KtzT-encoding genes were phylogenetically analyzed to classify the 23 clades into two monophyletic groups, I and II. Cultivating hit strains in media supplemented with 15NH4Cl and applying 1H-15N heteronuclear multiple bond correlation (HMBC) along with 1H-15N heteronuclear single quantum coherence (HSQC) and 1H-15N HSQC-total correlation spectroscopy (HSQC-TOCSY) NMR experiments detected the spectroscopic signatures of Piz and modified Piz. Chemical investigation of the hit strains prioritized by genomic and spectroscopic signatures led to the identification of a new azinothricin congener, polyoxyperuin B seco acid (1), previously reported chloptosin (2) in group I, depsidomycin D (3) incorporating two dehydropiperazic acids (Dpz), and lenziamides A and B (4 and 5), structurally novel 31-membered cyclic decapeptides in group II. By consolidating the phylogenetic and chemical analyses, clade-structure relationships were elucidated for 19 of the 23 clades. Lenziamide A (4) inhibited STAT3 activation and induced G2/M cell cycle arrest, apoptotic cell death, and tumor growth suppression in human colorectal cancer cells. Moreover, lenziamide A (4) resensitized 5-fluorouracil (5-FU) activity in both in vitro cell cultures and the in vivo 5-FU-resistant tumor xenograft mouse model. This work demonstrates that the genomic and spectroscopic signature-based searches provide an efficient and general strategy for new bioactive natural products containing specific structural motifs.

All-round catalytic and atroposelective strategy via dynamic kinetic resolution for N-/2-/3-arylindoles

As the complexity of organic molecules utilized by mankind increases, the phenomenon of atropisomerism is more frequently encountered. While a variety of well-established methods enable the control of a stereogenic center, a catalytic method for controlling a stereogenic axis in one substrate is typically unavailable for controlling axial chirality in other substrates with a similar structure. Herein, we report o-amidobiaryl as a flexible platform for chiral phosphoric acid-catalyzed atroposelective dynamic kinetic resolution. To demonstrate our strategy, three distinct types of arylindoles were utilized and reacted intermolecularly with ketomalonate in the presence of chiral phosphoric acid. An investigation of 46 substrates having an aromatic ring in different positions yields the desired products with excellent enantioselectivities. Computational investigation into the origin of enantioselectivity highlights the importance of the NH group. Given the biological significance of indoles, antiproliferative effects have been investigated; our scaffold exhibits good efficacy in this regard.

Midline catheters in the operating room

Backgrounds

Among various vascular access devices, midline catheters (MCs) are commonly used in emergency departments, but rarely in operating rooms.

Aims

To evaluate the feasibility and safety of MCs in the operating room.

Materials and Methods

This was a retrospective study. The medical records of patients who underwent MC placement in the operating room from October 2020 to July 2022 were reviewed. The rates of successful catheter insertion as well as major and minor complications were assessed.

Results

Successful catheter insertions were achieved in 149 of 161 patients (92.5%). The median dwell time of midlines was eight days (IQR: 6-10 days). A major or minor complication occurred in 6.7% of the midlines. The rates of major complications of occlusion, upper extremity deep vein thrombosis (DVT), and catheter-related bloodstream infection were 1.3%, 0.7%, and 0%, respectively.

Conclusions

Placement of MCs in the operating room was feasible and safe. Also, the procedure provides an acceptable alternative for replacing central line catheters and peripherally inserted central catheters.

Jejucarbosides B-E, Chlorinated Cycloaromatized Enediynes, from a Marine Streptomyces sp

Four new chlorinated cycloaromatized enediyne compounds, jejucarbosides B-E (1-4), were discovered together with previously-identified jejucarboside A from a marine actinomycete strain. Compounds 1-4 were identified as new chlorinated cyclopenta[a]indene glycosides based on 1D and 2D nuclear magnetic resonance, high-resolution mass spectrometry, and circular dichroism (CD) spectra. Jejucarbosides B and E bear a carbonate functional group whereas jejucarbosides C and D are variants possessing 1,2-diol by losing the carbonate functionality. It is proposed that the production of 1-4 occurs via Bergman cycloaromatization capturing Cl^- and H⁺ in the alternative positions of a p-benzyne intermediate derived from a 9-membered enediyne core. Jejucarboside E (4) displayed significant cytotoxicity against human cancer cell lines including SNU-638, SK-HEP-1, A549, HCT116, and MDA-MB-231, with IC₅₀ values of 0.31, 0.40, 0.25, 0.29, and 0.48 μM, respectively, while jejucarbosides B-D (1-3) showed moderate or no cytotoxic effects.

In Silico Discovery of 5'-Modified 7-Deoxy-7-ethynyl-4'-thioadenosine as a HASPIN Inhibitor and Its Synergistic Anticancer Effect with the PLK1 Inhibitor

Despite genetic perturbations resulting in embryo lethality for most mitotic kinases, loss of the histone H3 mitotic kinase HASPIN reveals no adverse effect in mice models, establishing HASPIN as a promising target for anticancer therapy. However, developing a HASPIN inhibitor from conventional pharmacophores poses a technical challenge as this atypical kinase shares slight similarities with eukaryotic protein kinases. Chemically modifying a cytotoxic 4'-thioadenosine analogue through high genotoxicity yielded several novel nongenotoxic kinase inhibitors. In silico apporoaches utilizing transcriptomic and chemical similarities with known compounds and KINOMEscan profiles unveiled the HASPIN inhibitor LJ4827. LJ4827's specificity and potency as a HASPIN inhibitor were verified through in vitro kinase assay and X-ray crystallography. HASPIN inhibition by LJ4827 reduced histone H3 phosphorylation and impeded Aurora B recruitment in cancer cell centromeres but not in noncancer cells. Through transcriptome analysis of lung cancer patients, PLK1 was determined as a druggable synergistic partner to complement HASPIN inhibition. Chemical or genetic PLK1 perturbation with LJ4827 effectuated pronounced lung cancer cytotoxicity in vitro and in vivo. Therefore, LJ4827 is a novel anticancer therapeutic for selectively impeding cancer mitosis through potent HASPIN inhibition, and simultaneous HASPIN and PLK1 interference is a promising therapeutic strategy for lung cancer.

Discovery and Biosynthesis of Cihunamides, Macrocyclic Antibacterial RiPPs with a Unique C-N Linkage Formed by CYP450 Catalysis

Cihunamides A-D (1-4), novel antibacterial RiPPs, were isolated from volcanic-island-derived Streptomyces sp. The structures of 1-4 were elucidated by 1 H, 13 C, and 15 N NMR, MS, and chemical derivatization; they contain a tetrapeptide core composed of WNIW, cyclized by a unique C-N linkage between two Trp units. Genome mining of the producer strain revealed two biosynthetic genes encoding a cytochrome P450 enzyme and a precursor peptide. Heterologous co-expression of the core genes demonstrated the biosynthesis of cihunamides through P450-mediated oxidative Trp-Trp cross-linking. Further bioinformatic analysis uncovered 252 homologous gene clusters, including that of tryptorubins, which possess a distinct Trp-Trp linkage. Cihunamides do not display the non-canonical atropisomerism shown in tryptorubins, which are the founding members of the "atropitide" family. Therefore, we propose to use a new RiPP family name, "bitryptides", for cihunamides, tryptorubins, and their congeners, wherein the Trp-Trp linkages define the structural class rather than non-canonical atropisomerism.

Synthesis and biological evaluation of atropisomeric tetrahydroisoquinolines overcoming docetaxel resistance in triple-negative human breast cancer cells

Herein, atropisomeric 8-aryltetrahydroisoquinolines have been synthesized and biologically evaluated. Based on our structure-activity relationship study, a highly bioactive racemic compound has been produced, and it exhibited high antiproliferative activities against various cancer cell lines, including docetaxel-resistant breast cancer cell lines. Each enantiomer can be synthesized in an enantioselective manner by employing the chiral phosphoric acid-catalyzed atroposelective Pictet-Spengler cyclization. An axially (R)-configured enantiomer showed a higher biological activity compared with the axially (S)-configured enantiomer. Further biological studies suggested that the (R)-enantiomer overcomes docetaxel resistance via the downregulation of signal transducer and activator of transcription 3 activation and consequently induces cellular apoptosis in docetaxel-resistant triple-negative breast cancer cell lines.

Scaffold hopping of N-benzyl-3,4,5-trimethoxyaniline: 5,6,7-Trimethoxyflavan derivatives as novel potential anticancer agents modulating hippo signaling pathway

Scaffold hopping of N-benzyl-3,4,5-trimethoxyaniline afforded 5,6,7-trimethoxyflavan derivatives that were efficiently synthesized in four linear steps. As lung cancer is the most lethal cancer, twenty-three synthesized compounds were evaluated against a panel of lung cancer cells. Amongst, compounds 8q and 8e showed interesting activity. Hence, compounds 8q and 8e were evaluated against panels of diverse cancers. Compounds 8q and 8e showed broad spectrum anticancer activity. However, compound 8q was more effective and, hence, was advanced for potency evaluation and characterization. Compound 8q showed comparable potencies to gefitinib, and oxaliplatin against lung and colorectal cancers, respectively, and superior potencies to temozolomide, dacarbazine, cisplatin, enzalutamide, methotrexate, imatinib against brain, skin, ovary, prostate, breast, and blood cancers, respectively. Compound 8q increased cleaved PARP, caspase 3, and 7 inducing apoptosis. In addition, it inhibited cyclins A, B₁, H and cdc25c, and increased p53 triggering cell cycle arrest in G₂/M phase. Moreover, it decreased YAP and increased LATS1 and p-mob1/mob1 activating hippo signaling. Furthermore, it decreased p-PI3K/PI3k, p-mTOR/mTOR and p-P70S6K/P70S6K inhibiting PI3k pathway. Together, these findings present compound 8q as a potential anticancer lead compound for further development of potential agents.

Antimetastatic Activity of Apoptolidin A by Upregulation of N-Myc Downstream-Regulated Gene 1 Expression in Human Colorectal Cancer Cells

Colorectal cancer (CRC) is one of the most prevalent tumors with high metastatic potential; consequently, finding new drug candidates that suppress tumor metastasis is essential. Apoptolidin A is a macrocyclic lactone produced by Amycolatopsis sp. DW02G. It exhibits significant cytotoxicity against several cancer cell lines, but its effects on CRC cells remain unknown. Therefore, the present study investigated the antiproliferative and antimetastatic activities of apoptolidin A and its underlying molecular mechanisms in CRC cells. Apoptolidin A effectively inhibited CRC cell growth and colony formation. The induction of G0/G1 phase cell cycle arrest was associated with the downregulation of cyclin D1 and CDK4/6 expression. Long-term exposure to apoptolidin A also induced apoptosis as confirmed by the downregulation and upregulation of Bcl-2 and Bax expression, respectively. Moreover, apoptolidin A effectively upregulated the suppressed expression of N-Myc downstream-regulated gene 1 (NDRG1), a tumor suppressor gene, in a concentration-dependent manner in CRC cells. The antimetastatic potential of apoptolidin A was also correlated with the expression of epithelial–mesenchymal transition (EMT) biomarkers, including the upregulation of E-cadherin and downregulation of N-cadherin, vimentin, snail, and MMP9 in CRC cells. These findings suggest that apoptolidin A exerts antiproliferative and antimetastatic activities by regulating the NDRG1-activated EMT pathway in CRC cells.

Search for the Pair Production of Dark Particles X with K_{L}^{0}→XX, X→γγ

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110  MeV/c^{2} and 210-240  MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

Effects of the administration of Shinbaro 2 in a rat lumbar disk herniation model

The current standard for the pharmacological management of lumbar disk herniation (LDH), involving non-steroidal anti-inflammatory drugs, muscle relaxants, and opioid analgesics, often carries a risk of adverse events. The search for alternative therapeutic options remains a vital objective, given the high prevalence of LDH and the critical impact on the quality of life. Shinbaro 2 is a clinically effective herbal acupuncture against inflammation and various musculoskeletal disorders. Therefore, we explored whether Shinbaro 2 exerts protective effects in an LDH rat model. The results showed that Shinbaro 2 suppressed pro-inflammatory cytokines, interleukin-1 beta, tumor necrosis factor-alpha, disk degeneration-related factors, matrix metalloproteinase-1,−3,−9, and ADAMTS-5 in LDH rats. Shinbaro 2 administration reinstated a behavioral activity to a normal level in the windmill test. The results indicated that Shinbaro 2 administration restored spinal cord morphology and functions in the LDH model. Therefore, Shinbaro 2 exerted a protective effect in LDH via actions on inflammatory responses and disk degeneration, indicating that future research is warranted to assess the action mechanisms further and validate its effects.

Involvement of cell shape and lipid metabolism in glioblastoma resistance to temozolomide

Temozolomide (TMZ) has been used as standard-of-care for glioblastoma multiforme (GBM), but the resistance to TMZ develops quickly and frequently. Thus, more studies are needed to elucidate the resistance mechanisms. In the current study, we investigated the relationship among the three important phenotypes, namely TMZ-resistance, cell shape and lipid metabolism, in GBM cells. We first observed the distinct difference in cell shapes between TMZ-sensitive (U87) and resistant (U87R) GBM cells. We then conducted NMR-based lipid metabolomics, which revealed a significant increase in cholesterol and fatty acid synthesis as well as lower lipid unsaturation in U87R cells. Consistent with the lipid changes, U87R cells exhibited significantly lower membrane fluidity. The transcriptomic analysis demonstrated that lipid synthesis pathways through SREBP were upregulated in U87R cells, which was confirmed at the protein level. Fatostatin, an SREBP inhibitor, and other lipid pathway inhibitors (C75, TOFA) exhibited similar or more potent inhibition on U87R cells compared to sensitive U87 cells. The lower lipid unsaturation ratio, membrane fluidity and higher fatostatin sensitivity were all recapitulated in patient-derived TMZ-resistant primary cells. The observed ternary relationship among cell shape, lipid composition, and TMZ-resistance may be applicable to other drug-resistance cases. SREBP and fatostatin are suggested as a promising target-therapeutic agent pair for drug-resistant glioblastoma.

Novel lignans from Zanthoxylum nitidum and antiproliferation activity of sesaminone in osimertinib-resistant non-small cell lung cancer cells

Seven previously undescribed tetrahydrofuran lignans with different configurations and unusual isopentenyl substitutions, nitidumlignans D-J (corresponding to compounds 1, 2, 4, 6, 7, 9 and 10), along with 14 known lignans, were isolated from Zanthoxylum nitidum. Notably, compound 4 is an uncommon naturally occurring furan-core lignan derived from tetrahydrofuran aromatization. The antiproliferation activity of the isolated compounds (1-21) was determined in various human cancer cell lines. The structure-activity study revealed that the steric positioning and chirality of the lignans exert important effects on their activity and selectivity. In particular, compound 3 (sesaminone) exhibited potent antiproliferative activity in cancer cells, including acquired osimertinib-resistant non-small-cell lung cancer (HCC827-osi) cells. Compound 3 also inhibited colony formation and induced the apoptotic death of HCC827-osi cells. The underlying molecular mechanisms revealed that 3 downregulated the activation of the c-Met/JAK1/STAT3 and PI3K/AKT/mTOR signaling pathways in the HCC827-osi cells. In addition, the combination of 3 and osimertinib exhibited synergistic effects on the antiproliferative activity against HCC827-osi cells. Overall, these findings inform the structure elucidation of novel lignans isolated from Z. nitidum, and sesaminone was identified as a potential compound for exerting antiproliferative effects on osimertinib-resistant lung cancer cells.

Design, Synthesis, and Biological Activity of Marinacarboline Analogues as STAT3 Pathway Inhibitors for Docetaxel-Resistant Triple-Negative Breast Cancer

Metastatic triple-negative breast cancer (mTNBC) is a fatal type of breast cancer (BC), and signal transducer and activator of transcription 3 (STAT3) has emerged as an effective target for mTNBC. In the present study, compound MC0704 was found to be a novel synthetic STAT3 pathway inhibitor, and its potential antitumor activity was demonstrated using in vitro and in vivo models in docetaxel-resistant TNBC cells. Based on marinacarboline (MC), a series β-carboline derivatives were synthesized and investigated for their antitumor activities against docetaxel-resistant MDA-MB-231 (MDA-MB-231-DTR) cells. Combining antiproliferation and STAT3 inhibitory activities, MC0704 was selected as the most promising β-carboline compound. MC0704 effectively impeded the metastatic potential of MDA-MB-231-DTR cells in vitro, and the combination of MC0704 and docetaxel exhibited potent antitumor activities in a xenograft mouse model. These findings suggested that MC0704 can be a lead candidate as a target therapeutic agent for TNBC patients with docetaxel resistance.

Discovery and structure elucidation of glycosyl and 5-hydroxy migrastatins from dung beetle gut Kitasatospora sp

Two new macrocyclic secondary metabolites, glycosyl-migrastatin (1) and 5-hydroxy-migrastatin (2), were isolated from a gut bacterium Kitasatospora sp. JL24 in dung beetle Onthophagus lenzii. Based on a comprehensive analysis of the nuclear magnetic resonance (NMR), MS, and UV spectroscopic data, the planar structures of 1 and 2 were successfully identified as new derivatives of migrastatin. Compound 1 was the first glycosylated member of the migrastatin family. The absolute configuration of the sugar moiety was determined to be d-glucose through the analysis of coupling constants and ROESY correlations, followed by chemical derivatization and chromatographic comparison with authentic d- and l-glucose. Compound 2, identified as 5-hydroxy-migrastatin possessing an additional hydroxy group with a previously unreported chiral center, was assigned using Mosher's method through 19F NMR chemical shifts and confirmed with the modified Mosher's method. Genomic analysis of Kitasatospora sp. strain JL24 revealed a putative biosynthetic pathway involving an acyltransferase-less type I polyketide synthase biosynthetic gene cluster.

ONE-SENTENCE SUMMARY

Two secondary metabolites, glycosyl-migrastatin (1) and 5-hydroxy-migrastatin (2), were discovered from the gut bacterium Kitasatospora sp. JL24 in the dung beetle Onthophagus lenzii.

Genomic and Spectroscopic Signature-Based Discovery of Natural Macrolactams

The logical and effective discovery of macrolactams, structurally unique natural molecules with diverse biological activities, has been limited by a lack of targeted search methods. Herein, a targeted discovery method for natural macrolactams was devised by coupling genomic signature-based PCR screening of a bacterial DNA library with spectroscopic signature-based early identification of macrolactams. DNA library screening facilitated the efficient selection of 43 potential macrolactam-producing strains (3.6% of 1,188 strains screened). The PCR amplicons of the amine-deprotecting enzyme-coding genes were analyzed to predict the macrolactam type (α-methyl, α-alkyl, or β-methyl) produced by the hit strains. ¹H-¹⁵N HSQC-TOCSY NMR analysis of ¹⁵N-labeled culture extracts enabled macrolactam detection and structural type assignment without any purification steps. This method identified a high-titer Micromonospora strain producing salinilactam (1), a previously reported α-methyl macrolactam, and two Streptomyces strains producing new α-alkyl and β-methyl macrolactams. Subsequent purification and spectroscopic analysis led to the structural revision of 1 and the discovery of muanlactam (2), an α-alkyl macrolactam with diene amide and tetraene chromophores, and concolactam (3), a β-methyl macrolactam with a [16,6,6]-tricyclic skeleton. Detailed genomic analysis of the strains producing 1-3 identified putative biosynthetic gene clusters and pathways. Compound 2 displayed significant cytotoxicity against various cancer cell lines (IC₅₀ = 1.58 μM against HCT116), whereas 3 showed inhibitory activity against Staphylococcus aureus sortase A. This genomic and spectroscopic signature-based method provides an efficient search strategy for new natural macrolactams and will be generally applicable for the discovery of nitrogen-bearing natural products.

Comparing the efficacy of different methods of faecal microbiota transplantation via oral capsule, oesophagogastroduodenoscopy, colonoscopy, or gastric tube

BACKGROUND

The increasing prevalence of multidrug-resistant organism (MDRO) carriage poses major challenges to medicine as healthcare costs increase. Recently, faecal microbiota transplantation (FMT) has been discussed as a novel and effective method for decolonizing MDRO.

AIM

To compare the efficacy of different FMT methods to optimize the success rate of decolonization in patients with MDRO carriage.

METHODS

This prospective cohort study enrolled patients with MDRO carriages from 2018 to 2021. Patients underwent FMT via one of the following methods: oral capsule, oesophagogastroduodenoscopy (EGD), colonoscopy, or gastric tube.

FINDINGS

A total of 57 patients underwent FMT for MDRO decolonization. The colonoscopy group required the shortest time for decolonization, whereas the EGD group required the longest (24.9 vs 190.4 days, P = 0.022). The decolonization rate in the oral capsule group was comparable to that in the EGD group (84.6% vs 85.7%, P = 0.730). An important clinical factor associated with decolonization failure was antibiotic use after FMT (odds ratio = 6.810, P = 0.008). All four groups showed reduced proportions of MDRO species in microbiome analysis after FMT.

CONCLUSION

Compared to other conventional methods, the oral capsule is an effective FMT method for patients who can tolerate an oral diet. The discontinuation of antibiotics after FMT is a key factor in the success of decolonization.

Undescribed isoquinolines from Zanthoxylum nitidum and their antiproliferative effects against human cancer cell lines

Eleven previously undescribed alkaloids, including three pairs of enantiomers nitidumalkaloids A-C, a pair of scalemic mixtures nitidumalkaloid D and three optically pure or achiral alkaloids, nitidumalkaloids E-G, along with 20 known alkaloids, were isolated from an ethanolic extract of the whole Zanthoxylum nitidum (Roxb.) DC plant. The chemical structures of the alkaloids were elucidated using a combination of comprehensive nuclear magnetic resonance (NMR) and high-resolution electro-spray ionization mass spectrometry (HR-ESI-MS) analyses. The configuration of the stereogenic centers of all undescribed compounds was precisely established based on single-crystal X-ray diffraction and electronic circular dichroism (ECD) calculations. Racemic mixtures of nitidumalkaloids A-D were purified, and their enantiomers were analyzed via chiral-phase high-performance liquid chromatography with electrochemical detection measurements (HPLC-ECD). Twelve compounds exhibited significant antiproliferative activities against a panel of cancer cell lines. Further studies were designed to investigate the underlying molecular mechanism of (1'S, 6R)-nitidumalkaloid B, which was the most active antiproliferative agent against human cancer A549 cells. G2/M cell cycle arrest, induction of apoptosis, and suppression of the Wnt/β-catenin signaling pathway were in part associated with the antiproliferative activity of (1'S, 6R)-nitidumalkaloid B. Moreover, (1'S, 6R)-nitidumalkaloid B inhibited cell migration by downregulating the epithelial-mesenchymal transition process in A549 cells. These data suggest that the antiproliferation activity of (1'S, 6R)-nitidumalkaloid B was correlated with the stereoselectivity of the stereoisomers, and (1'S, 6R)-nitidumalkaloid B was prioritized as a potential leading compound for the management of aggressive human non-small-cell lung cancer (NSCLC) from natural products.

Antitumor Activity of Piceamycin by Upregulation of N-Myc Downstream-Regulated Gene 1 in Human Colorectal Cancer Cells

Piceamycin (1), a macrocyclic lactam isolated from the silkworm's gut (Streptomyces sp. SD53 strain), reportedly possesses antibacterial activity. However, the potential anticancer activity and molecular processes underlying 1 have yet to be reported. Colorectal cancer (CRC) is high-risk cancer and accounts for 10% of all cancer cases worldwide. The high prevalence of resistance to radiation or chemotherapy means that patients with advanced CRC have a poor prognosis, with high recurrence and metastasis potential. Therefore, the present study investigated the antitumor effect and underlying mechanisms of 1 in CRC cells. The growth-inhibiting effect of 1 in CRC cells was correlated with the upregulation of a tumor suppressor, N-myc downstream-regulated gene 1 (NDRG1). Additionally, 1 induced G₀/G₁ cell cycle arrest and apoptosis and inhibited the migration of CRC cells. Notably, 1 disrupted the interaction between NDRG1 and c-Myc in CRC cells. In a mouse model with HCT116-implanted xenografts, the antitumor activity of 1 was confirmed by NDRG1 modulation. Overall, these findings show that 1 is a potential candidate for CRC treatment through regulation of NDGR1-mediated functionality.

Targeted Discovery of an Enediyne-Derived Cycloaromatized Compound, Jejucarboside A, from a Marine Actinomycete

A genomic and spectroscopic signature-based search revealed a cycloaromatized enediyne, jejucarboside A (1), from a marine actinomycete strain. The structure of 1 was determined as a new cyclopenta[a]indene glycoside bearing carbonate functionality by nuclear magnetic resonance, high-resolution mass spectrometry (MS), MS/MS, infrared spectroscopy, and a modified Mosher's method. An iterative enediyne synthase pathway has been proposed for the putative biosynthesis of 1 by genomic analysis. Jejucarboside A exhibited cytotoxicity against the HCT116 colon carcinoma cells.

Terminalia chebula Retz. extract ameliorates the symptoms of atopic dermatitis by regulating anti-inflammatory factors in vivo and suppressing STAT1/3 and NF-ĸB signaling in vitro

BACKGROUND

Terminalia chebula (TC) is a traditional medicinal plant used for treating various diseases in humans. However, pharmacological mechanisms underlying the effects of TC in atopic treatment remain unelucidated.

HYPOTHESIS/PURPOSE

We investigated the therapeutic effects of TC extract in a mouse model of atopic dermatitis (AD) in vivo and the anti-inflammatory mechanism in vitro.

STUDY DESIGN/METHODS

For the in vivo study, AD was induced by Dermatophagoides farinae extract (Dfe) in NC/Nga mice. After 14 days of oral administration, the effects of TC concentrations of 30, 100, and 300 mg/kg were analyzed by assessing morphological changes visually; measuring serum levels of inflammatory chemokines/cytokines, IgE, histamine, MDC, TARC, RANTES, and TSLP using ELISA kits; and counting infiltrated mast cells. For in vitro analyses, we used IFNγ/TNF-α-stimulated human keratinocyte cell lines to study the mechanism of action. The production of chemokines/cytokines in the IFNγ/TNF-α-stimulated HaCaT cells was measured using ELISA and a bead array kit. The signaling pathways were analyzed by western blotting and the expression of the transcriptional factors using RT-PCR and luciferase assay.

RESULTS

Administration of TC significantly alleviated AD-like symptoms in vivo and decreased the ear thickness, dermatitis score, keratinization, and mast cell infiltration. It also resulted in decreased serum levels of IgE, histamine, and inflammation-related mediators MDC, TARC, RANTES, and TSLP compared with those in the Dfe treatment group. Moreover, TC downregulated the expression of the inflammatory chemokines RANTES and MDC in IFNγ/TNF-α-stimulated HaCaT cells. TC inhibited phosphorylated STAT1/3 and NK-κB subunits and nuclear translocation of NF-κB. It also suppressed the transcription of IFNγ, IL-6, IL-8 and MCP-1 in the IFNγ/TNF-α-stimulated HaCaT cells. TC and its constituents, chebulic acid, gallic acid, corlagin, chebulanin, chbulagic acid, ellagic acid, and chebulinic acid, strongly inhibited the nuclear translocation of NF-κB, STAT1, and STAT3 and decreased the expression of inflammatory cytokines at the mRNA level.

CONCLUSIONS

Overall, TC extract alleviated AD-like symptoms by regulating anti-inflammatory factors in vivo and suppressing STAT1/3 and NF-κB signaling in vitro. In addition, our results show the in vivo effect of partial improvements in AD, as well as the in vitro effect on inflammatory factors by the constituents of TC. This finding provides that TC extract and its components could be potential therapeutic drugs for AD.

Establishment of Patient-Derived Pancreatic Cancer Organoids from Endoscopic Ultrasound-Guided Fine-Needle Aspiration Biopsies

Background/Aims

Three-dimensional cultures of human pancreatic cancer tissue also known as "organoids" have largely been developed from surgical specimens. Given that most patients present with locally advanced and/or metastatic disease, such organoids are not representative of the majority of patients. Therefore, we used endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to collect pancreatic cancer tissues from patients with advanced pancreatic cancer to create organoids, and evaluated their utility in pancreatic cancer research.

Methods

Single-pass EUS-FNA samplings were employed to obtain the tissue for organoid generation. After establishment of the organoid, we compared the core biopsy tissues with organoids using hematoxylin and eosin staining, and performed whole exome sequencing (WES) to detect mutational variants. Furthermore, we compared patient outcome with the organoid drug response to determine the potential utility of the clinical application of such organoid-based assays.

Results

Organoids were successfully generated in 14 of 20 tumors (70%) and were able to be passaged greater than 5 times in 12 of 20 tumors (60%). Among them, we selected eight pairs of organoid and core biopsy tissues for detailed analyses. They showed similar patterns in hematoxylin and eosin staining. WES revealed mutations in KRAS, TP53, CDKN2A, SMAD4, BRCA1, and BRCA2 which were 93% homologous, and the mean nonreference discordance rate was 5.47%. We observed moderate drug response correlations between the organoids and clinical outcomes in patients who underwent FOLFIRINOX chemotherapy.

Conclusions

The established organoids from EUS-FNA core biopsies can be used for a suitable model system for pancreatic cancer research.

Epoxinnamide: An Epoxy Cinnamoyl-Containing Nonribosomal Peptide from an Intertidal Mudflat-Derived Streptomyces sp

Cinnamoyl-containing nonribosomal peptides (CCNPs) form a unique family of actinobacterial secondary metabolites and display various biological activities. A new CCNP named epoxinnamide (1) was discovered from intertidal mudflat-derived Streptomyces sp. OID44. The structure of 1 was determined by the analysis of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) data along with a mass spectrum. The absolute configuration of 1 was assigned by the combination of advanced Marfey’s method, ³J_HH and rotating-frame overhauser effect spectroscopy (ROESY) analysis, DP4 calculation, and genomic analysis. The putative biosynthetic pathway of epoxinnamide (1) was identified through the whole-genome sequencing of Streptomyces sp. OID44. In particular, the thioesterase domain in the nonribosomal peptide synthetase (NRPS) biosynthetic gene cluster was proposed as a bifunctional enzyme, which catalyzes both epimerization and macrocyclization. Epoxinnamide (1) induced quinone reductase (QR) activity in murine Hepa-1c1c7 cells by 1.6-fold at 5 μM. It also exhibited effective antiangiogenesis activity in human umbilical vein endothelial cells (IC₅₀ = 13.4 μM).

Taeanamides A and B, Nonribosomal Lipo-Decapeptides Isolated from an Intertidal-Mudflat-Derived Streptomyces sp

Two new lipo-decapeptides, namely taeanamides A and B (1 and 2), were discovered from the Gram-positive bacterium Streptomyces sp. AMD43, which was isolated from a mudflat sample from Anmyeondo, Korea. The exact molecular masses of 1 and 2 were revealed by high-resolution mass spectrometry, and the planar structures of 1 and 2 were elucidated using NMR spectroscopy. The absolute configurations of 1 and 2 were determined using a combined analysis of ¹H-¹H coupling constants and ROESY correlations, the advanced Marfey’s method, and bioinformatics. The putative nonribosomal peptide synthetase pathway for the taeanamides was identified by analyzing the full genome sequence data of Streptomyces sp. AMD43. We also found that taeanamide A exhibited mild anti-tuberculosis bioactivity, whereas taeanamide B showed significant bioactivity against several cancer cell lines.

Antiproliferative Activity of a New Quinazolin-4(3H)-One Derivative via Targeting Aurora Kinase A in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is the most common lung cancer subtype. Although chemotherapy and targeted therapy are used for the treatment of patients with NSCLC, the survival rate remains very low. Recent findings suggested that aurora kinase A (AKA), a cell cycle regulator, is a potential target for NSCLC therapy. Previously, we reported that a chemical entity of quinazolin-4(3H)-one represents a new template for AKA inhibitors, with antiproliferative activity against cancer cells. A quinazolin-4(3H)-one derivative was further designed and synthesized in order to improve the pharmacokinetic properties and antiproliferation activity against NSCLC cell lines. The derivative, BIQO-19 (Ethyl 6-(4-oxo-3-(pyrimidin-2-ylmethyl)-3,4-dihydroquinazolin-6-yl)imidazo [1,2-a]pyridine-2-carboxylate), exhibited improved solubility and antiproliferative activity in NSCLC cells, including epidermal growth factor receptor–tyrosine kinase inhibitor (EGFR-TKI)-resistant NSCLC cells. BIQO-19 effectively inhibited the growth of the EGFR-TKI-resistant H1975 NSCLC cells, with the suppression of activated AKA (p-AKA) expression in these cells. The inhibition of AKA by BIQO-19 significantly induced G₂/M phase arrest and subsequently evoked apoptosis in H1975 cells. In addition, the combination of gefitinib and BIQO-19 exhibited synergistic antiproliferative activity in NSCLC cells. These findings suggest the potential of BIQO-19 as a novel therapeutic agent for restoring the sensitivity of gefitinib in EGFR-TKI-resistant NSCLC cells.

Antitumor Activity of Rutaecarpine in Human Colorectal Cancer Cells by Suppression of Wnt/β-Catenin Signaling

Alkaloids derived from natural products have been traditionally used to treat various diseases, including cancers. Rutaecarpine (1), a β-carboline-type alkaloid obtained from Evodia rutaecarpa, has been previously reported as an anti-inflammatory agent. Nonetheless, its anticancer activity and the underlying molecular mechanisms remain to be explored. In the procurement of Wnt/β-catenin inhibitors from natural alkaloids, 1 was found to exhibit activity against the Wnt/β-catenin-response reporter gene. Since the abnormal activation of Wnt/β-catenin signaling is highly involved in colon carcinogenesis, the antitumor activity and molecular mechanisms of 1 were investigated in colorectal cancer (CRC) cells. The antiproliferative activity of 1 was associated with the suppression of the Wnt/β-catenin-mediated signaling pathway and its target gene expression in human CRC cells. 1 also induced G₀/G₁ cell cycle arrest and apoptotic cell death, and the antimigration and anti-invasion potential of 1 was confirmed through epithelial-mesenchymal transition biomarker inhibition by the regulation of Wnt signaling. The antitumor activity of 1 was supported in an Ls174T-implanted xenograft mouse model via Wnt target gene regulation. Overall, these findings suggest that targeting the Wnt/β-catenin signaling pathway by 1 is a promising therapeutic option for the treatment of human CRC harboring β-catenin mutation.

Amentoflavone Promotes Cellular Uptake and Degradation of Amyloid-Beta in Neuronal Cells

Deposition of fibrillar forms of amyloid β-protein (Aβ) is commonly found in patients with Alzheimer's disease (AD) associated with cognitive decline. Impaired clearance of Aβ species is thought to be a major cause of late-onset sporadic AD. Aβ secreted into the extracellular milieu can be cleared from the brain through multiple pathways, including cellular uptake in neuronal and non-neuronal cells. Recent studies have showed that the naturally-occurring polyphenol amentoflavone (AMF) exerts anti-amyloidogenic effects. However, its effects on metabolism and cellular clearance of Aβ remain to be tested. In the present study, we demonstrated that AMF significantly increased the cellular uptake of both Aβ_1-40 and Aβ_1-42, but not inverted Aβ_42-1 in mouse neuronal N2a cells. Though AMF promoted internalization of cytotoxic Aβ_1-42, it significantly reduced cell death in our assay condition. Our data further revealed that the internalized Aβ is translocated to lysosomes and undergoes enzymatic degradation. The saturable kinetic of Aβ uptake and our pharmacologic experiments showed the involvement of receptor-mediated endocytosis, in part, through the class A scavenger receptors as a possible mechanism of action of AMF. Taken together, our findings indicate that AMF can lower the levels of extracellular Aβ by increasing their cellular uptake and clearance, suggesting the therapeutic potential of AMF for the treatment of AD.

Nyuzenamide C, an Antiangiogenic Epoxy Cinnamic Acid-Containing Bicyclic Peptide from a Riverine Streptomyces sp

A new nonribosomal peptide, nyuzenamide C (1), was discovered from riverine sediment-derived Streptomyces sp. DM14. Comprehensive analysis of the spectroscopic data of nyuzenamide C (1) revealed that 1 has a bicyclic backbone composed of six common amino acid residues (Asn, Leu, Pro, Gly, Val, and Thr) and four nonproteinogenic amino acid units, including hydroxyglycine, β-hydroxyphenylalanine, p-hydroxyphenylglycine, and 3,β-dihydroxytyrosine, along with 1,2-epoxypropyl cinnamic acid. The absolute configuration of 1 was proposed by J-based configuration analysis, the advanced Marfey's method, quantum mechanics-based DP4 calculations, and bioinformatic analysis of its nonribosomal peptide synthetase biosynthetic gene cluster. Nyuzenamide C (1) displayed antiangiogenic activity in human umbilical vein endothelial cells and induced quinone reductase in murine Hepa-1c1c7 cells.

Hamuramicin C, a Cytotoxic Bicyclic Macrolide Isolated from a Wasp Gut Bacterium

A new bicyclic macrolide, hamuramicin C (1), was isolated from Streptomyces sp. MBP16, a gut bacterial strain of the wasp Vespa crabro flavofasciata. Its 22-membered macrocyclic lactone structure was determined by NMR and mass spectrometry. The relative configurations of hamuramicin C (1) were assigned by J-based configuration analysis utilizing ¹H rotating frame Overhauser effect spectroscopy and heteronuclear long-range coupling NMR spectroscopy. Genomic and bioinformatic analyses of the bacterial strain enabled identification of the type-I polyketide synthase pathway, which employs a trans-acyltransferase system. The absolute configurations of 1 were proposed based on the analysis of the sequences of ketoreductases in the modular gene cluster. Moreover, hamuramicin C (1) demonstrated significant inhibitory activity against diverse human cancer cell lines (HCT116, A549, SNU-638, SK-HEP-1, and MDA-MB-231).

Gwanakosides A and B, 6-Deoxy-α-l-talopyranose-Bearing Aromatic Metabolites from a Streptomyces sp. and Coculture with Pandoraea sp

Single-strain cultivation of a mountain soil-derived Streptomyces sp. GA02 and its coculture with Pandoraea sp. GA02N produced two aromatic products, gwanakosides A and B (1 and 2, respectively). Their spectroscopic analysis revealed that 1 is a new dichlorinated naphthalene glycoside and 2 is a pentacyclic aromatic glycoside. The assignment of the two chlorine atoms in 1 was confirmed by the analysis of its band-selective CLIP-HSQMBC spectrum. The sugars in the gwanakosides were identified as 6-deoxy-α-l-talopyranose based on 1H-1H coupling constants, Rotating frame Overhauser enhancement spectroscopy (ROESY) NMR correlations, and chemical derivatization followed by spectroscopic and chromatographic analyses. The absolute configuration of 2, whose production was enhanced approximately 100-fold in coculture, was proposed based on a quantum mechanics-based chemical shift analysis method, DP4 calculations, and the chemically determined configuration of 6-deoxy-α-l-talopyranose. Gwanakoside A displayed inhibitory activity against pathogenic bacteria, including Staphylococcus aureus (MIC = 8 μg/mL) and Mycobacterium tuberculosis (MIC50 = 15 μg/mL), and antiproliferative activity against several human cancer cell lines (IC50 = 5.6-19.4 μM).

Ligiamycins A and B, Decalin-Amino-Maleimides from the Co-Culture of Streptomyces sp. and Achromobacter sp. Isolated from the Marine Wharf Roach, Ligia exotica

Streptomyces sp. GET02.ST and Achromobacter sp. GET02.AC were isolated together from the gut of the wharf roach, Ligia exotica, inhabiting the intertidal zone of the west coast of Korea. The co-cultivation of these two strains significantly induced the production of two new metabolites, ligiamycins A (1) and B (2), which were barely detected in the single culture of Streptomyces sp. GET02.ST. The planar structures of ligiamycins A (1) and B (2) were elucidated as new decalins coupled with amino-maleimides by the analysis of various spectroscopic data, including nuclear magnetic resonance (NMR), ultraviolet (UV), and mass (MS) data. The assignment of two nitrogen atoms in amino-maleimide in 1 was accomplished based on 1H-15N heteroatom single quantum coherence spectroscopy (HSQC) NMR experiments. The relative configurations of the ligiamycins were determined using rotating frame Overhauser effect spectroscopy (ROESY) NMR data, and their absolute configurations were deduced by comparing their experimental and calculated optical rotations. Ligiamycin A (1) displayed antibacterial effects against Staphylococcus aureus and Salmonella enterica, while ligiamycin B (2) exhibited mild cell cytotoxicity against human colorectal cancer cells.

Risk factors for scabies treatment resistance: a retrospective cohort study

BACKGROUND

In order to successfully treat scabies and to prevent its spread, it is important to identify the factors that can influence the outcome of scabies treatment.

OBJECTIVES

This study was designed to evaluate the risk factors associated with treatment resistance scabies during use of an effective topical medication.

METHODS

A retrospective cohort study was performed in patients with scabies infestations confirmed by potassium hydroxide (KOH) examinations. Patient characteristics, clinical features and treatment history were collected. The treatment resistance group included patients with persistent scabies infestations for more than 28 days after initiation of antiscabies treatment with 5% permethrin cream.

RESULTS

In total, 138 patients with scabies infestations treated between January 2017 and December 2020 were included in this study. Of these, 100 (72.5%) patients were treated successfully, while 38 (27.5%) patients experienced treatment resistance. In the univariable analysis, risk factors for treatment resistance scabies included impaired cognitive function (OR = 2.66, 95% CI, 1.15-6.14), limited mobility (OR = 2.97, 95% CI, 1.30-6.83), inpatient status (vs. outpatient, OR = 3.3, 95% CI, 1.28-8.54), topical steroid use before diagnosis (OR = 3.52, 95% CI, 1.61-7.81), systemic steroid use before diagnosis (OR = 3.57, 95% CI, 1.26-10.34) and a positive KOH exam after the first treatment (OR = 7.25, 95% CI, 3.24-17.11). In the multivariable analysis, limited mobility (OR = 3.46, 95% CI, 1.02-12.11) and topical steroid use before diagnosis (OR = 3.65, 95% CI, 1.41-9.75) were significant predictive factors for treatment resistance scabies.

CONCLUSIONS

Scabies patients with limited mobility and topical steroid use before diagnosis are at high risk of treatment resistance. Dermatologists should take these findings into consideration when treating patients with scabies infestations.

Cinnamomum verum-derived O-methoxycinnamaldehyde prevents lipopolysaccharide-induced depressive-like behavior in mice via NFAT mRNA stability in T lymphocytes

BACKGROUND

Depressive-like behaviors are related to inflammatory immune activation. Cinnamomum verum (CV) has anti-inflammatory effects, but the molecular mechanisms underlying the antidepressant effects after immunological activation still remain elusive.

PURPOSE

The aim of the present study was to investigate the effect of CV in improving depressive-like behavior and explore its underlying mechanism in T lymphocytes.

METHODS

Mice were randomly divided into Control, LPS, LPS plus fluoxetine, LPS plus CV, and LPS plus MCA groups. Behavior was evaluated using forced swimming test (FST) and tail suspension test (TST). The experimental group mice were exposed to LPS to induce depressive-like behavior. Cell viability was measured upon treating splenic T lymphocytes and Jurkat T cells with CV. Cytokine activity was measured using ELISA and RT-qPCR. The components of CV were analyzed by HPLC. NFAT expression was evaluated by western blotting, immunofluorescence, and luciferase assay. To verify the half-life of NFAT mRNA, Jurkat cells were treated with actinomycin D for 1.5, 3, and 4.5 h.

RESULTS

CV effectively prevents inflammation-induced depressive-like behaviors. CV dose-dependently decreased protein and mRNA levels of TNFα and IL-2. Inhibition of TNFα and IL-2 production involves an MCA-mediated decrease in NFAT mRNA level, rather than inhibition of nuclear translocation. This mechanism was independent of NFAT transcription inducer p38 MAPK; it can be attributed to the promotion of NFAT mRNA decay.

CONCLUSION

Overall, MCA might be an alternative or adjuvant to existing NFAT-targeting immunosuppressants for clinical prophylaxis or therapy in the context of inflammation-induced depressive disorder or other T-cell-associated inflammatory disorders.