Structurally Diverse Alkaloids with Anti-Renal-Fibrosis Activity from the Centipede Scolopendra subspinipes mutilans.

Twelve new alkaloids, scolopenolines A-L (1-7, 9-11, 13, 14), along with six known analogues, were isolated from Scolopendra subspinipes mutilans, identified by analysis of spectroscopic data and quantum chemical and computational methods. Scolopenoline A (1), a unique guanidyl-containing C14 quinoline alkaloid, features a 6/6/5 ring backbone. Scolopenoline B (2) is a novel sulfonyl-containing heterodimer comprising quinoline and tyramine moieties. Scolopenoline G (7) presents a rare C12 quinoline skeleton with a 6/6/5 ring system. Alkaloids 1, 8, 10, and 15-18 display anti-inflammatory activity, while 10 and 16-18 also exhibit anti-renal-fibrosis activity. Drug affinity responsive target stability and RNA-interference assays show that Lamp2 might be a potentially important target protein of 16 for anti-renal-fibrosis activity.

Nematicidal Activity of 20-Deoxyingenol-3-angelate from Euphorbia peplus Latex Through Protein Kinase C Isotype TPA-1.

The latex of Euphorbia peplus and its major component 20-deoxyingenol-3-angelate (DI3A) displayed significant nematicidal activity against Caenorhabditis elegans and Panagrellus redivivus. DI3A treatment inhibited the growth and development of nematodes and caused significantly negative effects on locomotion behavior, reproduction, and accumulation of reactive oxygen species. Transcriptome analysis indicated that differential expression genes in DI3A-treated C. elegans were mainly associated with the metabolism, growth, and development process, which were further confirmed by RT-qPCR experiments. The expression level of TPA-1 gene encoding a protein kinase C isotype was obviously upregulated by DI3A treatment, and knockdown of TPA-1 by RNAi technology in the nematode could relieve the growth-inhibitory effect of DI3A. Metabolic analysis indicated that DI3A was hardly metabolized by C. elegans, but a glycosylated indole derivative was specifically accumulated likely due to the activation of detoxification. Overall, our findings suggested that DI3A from E. peplus latex exerted a potent nematicidal effect through the gene TPA-1, which provides a potential target for the control of nematodes and also suggests the potential application value of E. peplus latex and DI3A as botanical nematicides.

Unusual immunosuppressive pyridine-containing bisnor- (c23), tetranor- (c21) and pentanor- (c20) sesterterpenoids from Tibetan Leucosceptrum canum.

An unusual pyridine-containing sesterterpenoid, leucosceptrodine (1), and five new nor-leucosceptrane sesterterpenoids, including bisnor- (C23, 2), tetranor- (C21, 3) and pentanor- (C20, 4-6) skeletons, were isolated from the leaves of Tibetan Leucosceptrum canum. Their structures including their absolute configurations were determined by extensive spectroscopic analyses and quantum chemical calculations. A single crystal of one epimer (5) was crystallized from a pair of inseparable epimers, and its structure including its absolute configuration was determined by X-ray crystallographic analysis. The immunosuppressive activities of compounds 1-4 with different potencies were evaluated by inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.

Syntheses of Linear Biosynthetic C25-Precursors of Leucosceptroids.

An efficient synthetic approach was developed and applied to the syntheses of four linear biosynthetic C25-precursors of leucosceptroids. The synthesis features a Julia-Kocienski olefination and a late-stage bioinspired photo-oxidation as key steps. The immunosuppressive effects of all synthetic compounds on mouse T cells and macrophage RAW264.7 were determined.

Exploration of the profiles of steroidal saponins from Rhizoma Paridis and their metabolites in rats by UPLC-Q-TOF-MS/MS.

INTRODUCTION: Steroidal saponins characterised by intricate chemical structures are the main active components of a well-known traditional Chinese medicine (TCM) Rhizoma Paridis. The metabolic profiles of steroidal saponins in vivo remain largely unexplored, despite their renowned antitumor, immunostimulating, and haemostatic activity. OBJECTIVE: To perform a comprehensive analysis of the chemical constituents of Rhizoma Paridis total saponins (RPTS) and their metabolites in rats after oral administration. METHOD: The chemical constituents of RPTS and their metabolites were analysed using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS). RESULTS: A reliable UPLC-Q-TOF-MS/MS method was established, and a total of 142 compounds were identified in RPTS. Specifically, diosgenin-type saponins showed the diagnostic ions at m/z 415.32, 397.31, 283.25, 271.21, and 253.20, whereas pennogenin-type saponins exhibited the diagnostic ions at m/z 413.31, 395.30, and 251.20. Based on the characteristic fragments and standard substances, 15 specific metabolites were further identified in the faeces, urine, plasma, and bile of rats. The metabolic pathways of RPTS, including phase I reactions (de-glycosylation and oxidation) and phase II reactions (glucuronidation), were explored and summarised, and the enrichment of metabolites was characterised by multivariate statistical analysis. CONCLUSION: The intricate RPTS could be transformed into relatively simple metabolites in rats through de-glycosylation, which provides a reference for further metabolic studies and screening of active ingredients for TCM.

New triterpenoids from the aerial parts of the Uygur medicine Salvia deserta.

Phytochemical investigation on the aerial parts of Salvia deserta led to the isolation of eight new pentacyclic triterpenoids including three oleanane- (1 - 3) and five ursane-type (4 - 8) triterpenoids, whose structures were elucidated based on extensive spectroscopic analysis and quantum chemical calculation. Weak immunosuppressive potency was observed for compounds 1, 2, and 4 - 8 via inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced macrophages RAW264.7 at 20 µM. In addition, compounds 1, 2, and 4 - 6 exhibited moderate protective activity on t-BHP-induced oxidative injury in HepG2 cells.

Leucosceptrane Sesterterpenoids as a New Type of Natural Immunosuppressive Agents in Treating Sepsis.

Intragastric administration of the total sesterterpenoid extract (TSE) of medicinal plant Leucosceptrum canum at 2.5 g/kg dose protected mice from LPS-induced sepsis. Phytochemical investigation led to the isolation and identification of 47 leucosceptrane sesterterpenoids (1-47) including 30 new compounds (1-30) with complicated oxygenation patterns. Biological screening indicated their immunosuppressive activity via inhibiting IFN-γ secretion and/or proliferation of T cells with different potencies. Mechanism study of compounds 9, 25, and 32 revealed that they inhibited the activations of AKT-mTOR, JNK, p38 MAPK or ERK pathway in T cells and macrophages. In addition, compounds 9 and 25 induced G0/G1 cell arrest of T cells. The major component, leucosceptroid N (32), significantly lowered the levels of IL-6 and TNF-α in peripheral blood serum, and ameliorated the multiorgan damages of LPS-induced sepsis mice at 25 mg/kg dose. These findings suggest that leucosceptrane sesterterpenoids are a new type of potential immunosuppressive agents for sepsis treatment.

Discovery of Unusual Sesterterpenoids from Colquhounia coccinea var. mollis and Their Metabolic Implications.

Three unusual sesterterpenoids featuring unprecedented rearranged colquhounane (C25) and tetranorcolquhounane (C21) frameworks, colquhounoids E (1) and F (3) and norcolquhounoid F (2), were isolated from a Lamiaceae medicinal plant Colquhounia coccinea var. mollis. Their structures were elucidated by spectroscopic analysis and quantum chemical calculations. A biomimetic inspired regioselective cyclopropane cleavage was achieved under acidic conditions. The immunosuppressive activities of these new sesterterpenoids were also evaluated.

Defensive furofuran lignans localized to the oil cells of Neocinnamomum delavayi and their metabolism by a specialist insect.

Neocinnamomum delavayi (Lauraceae) leaves with abundant oil cells are seldom attacked by insects, but their chemical constituent and biological function remain obscure. Three furofuran lignans, including (+)-eudesmin (3), (+)-magnolin (4), and demethoxyaschantin (5), were identified to be the major specialized metabolites in the oil cells of N. delavayi leaves through laser microdissection coupled with NMR analysis. Compounds 3 and 4 exhibited obvious antifeedant activity against a generalist insect Spodoptera exigua, and their natural contents in the leaves could effectively defend against generalist insects. Intriguingly, three specific metabolites 9-11, the O-demethylation derivates of compounds 3-5, were identified from a native specialist insect Dindica polyphaenaria feeding with N. delavayi leaves, implying an adaptation mechanism of specialist insects to plant defensive compounds. The results revealed a chemical connection between plants and insects, which would contribute to our understanding of plant-insect interaction and insect management.

Clerodane diterpenoids from the Uygur medicine Salvia deserta with immunosuppressive activity.

Six undescribed clerodane diterpenoids along with five known ones were isolated from the aerial parts of Salvia deserta, a traditional Uygur medicine. Their chemical structures including absolute configurations were elucidated by extensive spectroscopic analysis (including 1D and 2D NMR, HRESIMS, and IR), combined with calculated ECD method and single-crystal X-ray diffraction analysis. All the compounds possessed a terminal α,ß-unsaturated-γ-lactone moiety, and were assayed for their immunosuppressive activity via inhibiting the secretion of cytokines TNF-α and IL-6 in macrophages RAW264.7. Among them, (5R,8R,9S,10R)-18-nor-cleroda-2,13-dien-16,15-olide-4-one obviously suppressed the secretion of TNF-α and IL-6 with IC50 values of 8.55 and 13.65 µM, respectively.

A new sesquiterpene synthase catalyzing the formation of (R)-ß-bisabolene from medicinal plant Colquhounia coccinea var. mollis and its anti-adipogenic and antibacterial activities.

The sesquiterpene ß-bisabolene possessing R and S configurations is commonly found in plant essential oils with antimicrobial and antioxidant activities. Here, we report the cloning and functional characterization of a (R)-ß-bisabolene synthase gene (CcTPS2) from a Lamiaceae medicinal plant Colquhounia coccinea var. mollis. The biochemical function of CcTPS2 catalyzing the cyclization of farnesyl diphosphate to form a single product (R)-ß-bisabolene was characterized through an engineered Escherichia coli producing diverse polyprenyl diphosphate precursors and in vitro enzyme assay, indicating that CcTPS2 was a high-fidelity (R)-ß-bisabolene synthase. The production of (R)-ß-bisabolene in an engineered E. coli strain harboring the exogenous mevalonate pathway, farnesyl diphosphate synthase and CcTPS1 genes was 17 mg/L under shaking flask conditions. Ultimately, 120 mg of purified (R)-ß-bisabolene was obtained from the engineered E. coli, and its structure was elucidated by detailed spectroscopic analyses (including 1D and 2D NMR, and specific rotation). Four chimeric enzymes were constructed through domain swapping, which altered the product outcome, indicating the region important for substrate and product specificity. In addition, (R)-ß-bisabolene exhibited anti-adipogenic activity in the model organism Caenorhabditis elegans and antibacterial activity selectively against Gram-positive bacteria.

Secoiridoids from the traditional Chinese medicine Swertia pseudochinensis.

Detailed phytochemical investigation on the traditional Chinese medicine Swertia pseudochinensis Hara led to the isolation of ten undescribed secoiridoids and fifteen known analogs. Their structures were elucidated by extensive spectroscopic analysis (including 1D and 2D NMR, and HRESIMS). Selected isolates were assayed for their anti-inflammatory and antibacterial activities, and moderate anti-inflammatory activity via inhibiting the secretion of cytokines IL-6 and TNF-α in macrophages RAW264.7 induced by LPS were observed. Antibacterial activity against Staphylococcus aureus was not found at 100 µM.

The activation of FPR3/PKA/Rap1/ERK1/2 and FPR3/p-IκB/NF-κB axis in fibroblasts promote capsular contracture after rhinoplasty.

BACKGROUND: Capsular contracture may occur after rhinoplasty due to rejection of silicone implants by the immune system. Our previous high-throughput sequencing of RNA in nasal capsular contracture tissue revealed that FPR3 was significantly increased in grade IV capsular contracture tissue, compared with grade II. OBJECTIVE: This study aimed to elucidate the effect and specific mechanism of FPR3 on capsular formation and contracture following rhinoplasty. METHODS: Using the GeneMANIA Database, the genes involved with FPR3 expression were searched, and the Gene Ontology analysis was performed to annotate the biological functions of the aforementioned genes. The mRNA and protein expressions of related genes in fibroblasts and capsular contracture tissues were analyzed using quantitative real-time PCR, western blot, and immunohistochemical staining. CCK-8 was used to determine the viability of cells. The migration capacity of fibroblasts was assessed using a wound healing assay. ELISA was used to detect levels of IL-1ß, TNF-α, and IL-6. RESULTS: After rhinoplasty, the expression of FPR3 in the capsular tissue increased in proportion to the degree of contracture. By activating the PKA/Rap1/ERK1/2 axis, overexpression of FPR3 can significantly increase the cell viability of fibroblasts and promote their transformation into myofibroblasts. Moreover, FPR3 phosphorylates IκB to decrease NF-κB inhibition, thereby promoting the synthesis and release of the inflammatory cytokines IL-1ß, TNF-α, and IL-6. CONCLUSION: FPR3 is a crucial molecule that causes capsular development and contracture following rhinoplasty. In the future, local suppression of FPR3 may be an effective treatment for relieving capsular contracture.

Secondary metabolites from the Mongolian medicine Lomatogonium carinthiacum.

Systematic phytochemical investigation on the Mongolian medicinal herb Lomatogonium carinthiacum led to the isolation of 12 monoterpenoids including three new secoiridoids (1, 2 and 4) and one new iridoid glycoside (13), one new monoterpenoid alkaloid (3), and three new sesquiterpenoids (14-16). Comprehensive spectroscopic analysis (including 1D and 2D NMR, and HRESIMS) and quantum chemistry computations (including ECD and NMR calculations) were applied to elucidate their structures. Weak immunosuppressive activities were observed for the new isolates via inhibiting T cell proliferation and cytokine IFN-γ secretion in vitro.

Labdane diterpenoids from the heartwood of Leucosceptrum canum that impact on root growth and seed germination of Arabidopsis thaliana.

Eleven undescribed diterpenoids possessing labdane, 3,18-cyclo-labdane, 19 (4 â†’ 3)-labdane and 12-nor-labdane skeletons, named leucolactones A-K, were isolated from the heartwood of a large woody Lamiaceae plant, Leucosceptrum canum. Their structures were determined by NMR, MS, and in the case of leucolactones A by single crystal X-ray diffraction analysis. Plausible biosynthetic pathway of leucolactones were proposed. Leucolactones showed significant inhibitory effects against seed germination and root elongation of Arabidopsis thaliana in the Petri dish bioassay. Among them, the diastereomeric leucolactones G and H were the most potent, with EC50 values for root elongation of 6.53 ± 1.35 and 9.75 ± 1.25 µM, respectively. The preliminary structure-activity relationship of leucolactones was discussed. The increase of auxin reporter activity in A. thaliana DR5::GUS roots by leucolactone H was observed, indicating that leucolactones altered auxin accumulation and distribution. These findings suggested that leucolactones might be involved in regulation of plant growth and development through altering auxin accumulation and distribution, presumably contributing to the heartwood formation in L. canum.

Chemical investigation of Buddleja officinalis leaves and localization of defensive triterpenoids to its glandular trichomes.

Buddleja officinalis is a traditional Chinese medicinal plant covered with glandular and non-glandular trichomes on leaves. Phytochemical investigation of its leaves led to the identification of one undescribed tetranorcycloartane 3-oxo-25,26,27,29-tetranorcycloartan-24-oic acid (1) and one first identified natural product tetranorcycloartane 3-oxo-25,26,27,29-tetranorcycloartan-24-oic methyl ester (2), along with an undescribed megastigmane glucoside (3) and 14 known constituents (4-17). Structures of undescribed chemicals were elucidated by comprehensive 1D and 2D NMR, MS and CD analysis. Further chemical investigation resulted in six triterpenoids (4-9) being localized to the trichomes of B. officinalis. The major trichome components cycloeucalenone (4) and 24-oxo-29-norcycloartan-3-one (5) showed potent antifeedant activity against a generalist insect cotton bollworm (Helicoverpa armigera), but no obvious activity against the specialist herbivore Hyphasis inconstans. Compounds 4 and 7 also displayed inhibitory effects on seed germination of Arabidopsis thaliana. In addition, 1 and 4 exhibited moderate antibacterial activity toward three gram-positive bacteria.

Surgical amputation for patients with diabetic foot ulcers: A Chinese expert panel consensus treatment guide.

Background: Diabetic foot disease is a serious complication of diabetes mellitus. Patients with diabetes mellitus have a 25% lifetime risk for developing a foot ulcer, and between 14% and 24% of patients require a major or minor lower limb amputation due to severe gangrene. However, decisions concerning whether to amputate or whether to perform a major or minor lower limb amputation, and how best to determine the amputation plane remain unclear. Methods: To consolidate the current literature with expert opinion to make recommendations that will guide surgical amputation for patients with diabetic foot ulcers. A total of 23 experts experienced in surgical treatment of patients with diabetic foot ulcers formed an expert consensus panel, and presented the relevant evidence, discussed clinical experiences, and derived consensus statements on surgical amputation for patients with diabetic foot ulcers. Each statement was discussed and revised until a unanimous consensus was achieved. Results: A total of 16 recommendations for surgical amputation for patients with diabetic foot ulcers were formulated. The experts believe that determination of the amputation plane should be comprehensively evaluated according to a patient's general health status, the degree of injury, and the severity of lower limb vasculopathy. The Wagner grading system and the severity of diabetic lower extremity artery disease are important criteria when determining the degree of amputation. The severity of both diabetic foot infection and systemic underlying diseases are important factors when considering appropriate treatment. Moreover, consideration should also be given to a patient's socioeconomic status. Given the complexities of treating the diabetic foot, relevant issues in which consensus could not be reached will be discussed and revised in future. Conclusion: This expert consensus could be used to guide doctors in clinical practice, and help patients with diabetic foot ulcers gain access to appropriate amputation treatment.

Novel IKZF3 transcriptomic signature correlates with positive outcomes of skin cutaneous melanoma: A pan-cancer analysis.

To investigate the potential relationship between Ikaros family genes and skin cutaneous melanoma (SKCM), we undertook a pan-cancer analysis of the transcriptional signature and clinical data of melanoma through multiple databases. First, 10,327 transcriptomic samples from different cancers were included to determine the overall characteristics and clinical prognoses associated with Ikaros gene expression across cancer types. Second, differentially expressed genes analysis, prognostic evaluation, and gene set enrichment analysis were employed to investigate the role of Ikaros (IKZF) genes in SKCM. Third, we evaluated the relationship between Ikaros family genes and SKCM immune infiltrates and verified the findings using the GEO single-cell sequencing dataset. The results show that Ikaros genes were widely expressed among different cancer types with independently similar patterns as follows: 1. IKZF1 and IKZF3, and 2. IKZF2 and IKZF4-5. IKZF2 and IKZF5 were downregulated in the primary tumor, and IKZF1-3 expression decreased significantly as the T-stage or metastasis increased in SKCM. Moreover, high IKZF1-3 expression was associated with better overall survival, disease-specific survival, and progression-free interval. IKZF3 is an independent prognostic factor of SKCM. Among Ikaros genes, the expression of IKZF1 and IKZF3 positively correlated with the infiltration level of CD4+ T cells and CD8+ T cells, B cells, and Tregs in SKCM and negatively correlated with the infiltration level of M0 and M1 macrophages. Moreover, single-cell sequencing data analysis revealed that IKZF1 and IKZF3 were mainly expressed by immune cells. Correlation analysis shows the immune factors and drug responses associated with IKZF3 expression. In conclusion, the present study is the first, to our knowledge, to identify a pan-cancer genomic signature of the Ikaros gene family among different cancers. Expression of these family members, particularly high levels of IKZF3, indicate positive immunological status and beneficial clinical outcomes of SKCM. IKZF3 may therefore serve as potential targets for immunotherapy of melanoma.

KIO3-Mediated γ-C(sp3)-H Sulfenylation of Enaminones.

A metal-free regioselective γ-C(sp3)-H sulfenylation of enaminones with heterocyclic thiols is reported. This transformation is efficient, mild, scalable, and environmentally friendly and tolerates a large variety of enaminones substrates and heterocyclic thiols. The utility of this strategy is demonstrated in a late-stage modification of bioactive natural products and drug derivatives.

An extremely promiscuous terpenoid synthase from the Lamiaceae plant Colquhounia coccinea var. mollis catalyzes the formation of sester-/di-/sesqui-/mono-terpenoids.

Terpenoids are the largest class of natural products with complex structures and extensive bioactivities; their scaffolds are generated by diverse terpenoid synthases (TPSs) from a limited number of isoprenoid diphosphate precursors. Promiscuous TPSs play important roles in the evolution of terpenoid chemodiversity, but they remain largely unappreciated. Here, an extremely promiscuous terpenoid synthase (CcTPS1) of the TPS-b subfamily was cloned and functionally characterized from a leaf-specific transcriptome of the Lamiaceae plant Colquhounia coccinea var. mollis. CcTPS1 is the first sester-/di-/sesqui-/mono-TPS identified from the plant kingdom, accepting C25/C20/C15/C10 diphosphate substrates to generate a panel of sester-/di-/sesqui-/mono-terpenoids. Engineered Escherichia coli expressing CcTPS1 produced three previously unreported terpenoids (two sesterterpenoids and a diterpenoid) with rare cyclohexane-containing skeletons, along with four sesquiterpenoids and one monoterpenoid. Their structures were elucidated by extensive nuclear magnetic resonance spectroscopy. Nicotiana benthamiana transiently expressing CcTPS1 also produced the diterpenoid and sesquiterpenoids, demonstrating the enzyme's promiscuity in planta. Its highly leaf-specific expression pattern combined with detectable terpenoid products in leaves of C. coccinea var. mollis and N. benthamiana expressing CcTPS1 suggested that CcTPS1 was mainly responsible for diterpenoid and sesquiterpenoid biosynthesis in plants. CcTPS1 expression and the terpenoid products could be induced by methyl jasmonate, suggesting their possible role in plant-environment interaction. CcTPS1 was localized to the cytosol and may differ from mono-TPSs in subcellular compartmentalization and substrate tolerance. These findings will greatly aid our understanding of plant TPS evolution and terpenoid chemodiversity; they also highlight the enormous potential of transcriptome mining and heterologous expression for the exploration of unique enzymes and natural products hidden in plants.