Extraction and Fractionation of Bioactives from Dipsacus fullonum L. Leaves and Evaluation of Their Anti-Borrelia Activity

Lyme disease (LD) is a tick-borne bacterial disease that is caused by Borrelia burgdorferi. Although acute LD is treated with antibiotics, it can develop into relapsing chronic form caused by latent forms of B. burgdorferi. This leads to the search for phytochemicals against resistant LD. Therefore, this study aimed to evaluate the activity of Dipsacus fullonum L. leaves extract (DE) and its fractions against stationary phase B. burgdorferi in vitro. DE showed high activity against stationary phase B. burgdorferi (residual viability 19.8 ± 4.7%); however, it exhibited a noticeable cytotoxicity on NIH cells (viability 20.2 ± 5.2%). The iridoid-glycoside fraction showed a remarkable anti-Borrelia effect and reduced cytotoxicity. The iridoid-glycoside fraction was, therefore, further purified and showed to contain two main bioactives—sylvestrosides III and IV, that showed a considerable anti-Borrelia activity being the least toxic to murine fibroblast NIH/3T3 cells. Moreover, the concentration of sylvestrosides was about 15% of DE, endorsing the feasibility of purification of the compounds from D. fullonum L. leaves.

Identification of Chemical Components of Qi-Fu-Yin and Its Prototype Components and Metabolites in Rat Plasma and Cerebrospinal Fluid via UPLC-Q-TOF-MS

Qi-Fu-Yin, a traditional Chinese medicine formula, has been used to treat Alzheimer’s disease (AD, a neurodegenerative disorder) in clinical setting. In this study, the chemical components of Qi-Fu-Yin and its prototype components and metabolites in rat plasma and cerebrospinal fluid, after oral administration, were preliminarily characterized via ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS). A total of 180 compounds, including saponins, flavonoids, organic acids, sucrose esters, oligosaccharide esters, phthalides, phenylethanoid glycosides, alkaloids, xanthones, terpene lactones, ionones, and iridoid glycoside, were tentatively characterized. For the first time, 51 prototypical components and 26 metabolites, including saponins, phthalides, flavonoids, sucrose esters, organic acids, alkaloids, ionones, terpene lactones, iridoid glycoside, and their derivatives, have been tentatively identified in the plasma. Furthermore, 10 prototypical components (including butylidenephthalide, butylphthalide, 20(S)-ginsenoside Rh1, 20(R)-ginsenoside Rh1, and zingibroside R1) and 6 metabolites were preliminarily characterized in cerebrospinal fluid. These results were beneficial to the discovery of the active components of Qi-Fu-Yin anti-AD.

Capturing Acyltransferase(s) Transforming Final Step in the Biosynthesis of a Major Iridoid Glycoside, (Picroside-II) in a Himalayan Medicinal Herb, Picrorhiza kurroa

BackgroundPicrorhiza kurroa has been reported as an age-old ayurvedic hepatoprotection to treat hepatic disorders due to the presence of iridoids such as picroside-II (P-II), picroside-I, and kutkoside. The acylation of catalpol and vanilloyl coenzyme A by acyltransferases (ATs) is critical step in P-II biosynthesis. Since accumulation of P-II occurs only in roots, rhizomes and stolons, uprooting of this critically endangered herb has been the only source of this compound. Recently, we reported that P-II acylation likely happen in roots, while stolons serve as the vital P-II storage compartment. Therefore, developing an alternate engineered platform for P-II biosynthesis require identification of P-II specific AT/s.Methods and results In that direction, egg-NOG function annotated 815 ATs from de novo RNA sequencing of tissue culture based ‘shoots-only’ system and nursery grown shoots, roots, and stolons varying in P-II content, were cross-compared in silico to arrive at ATs sequences unique and/or common to stolons and roots. Verification for organ and accession-wise upregulation in gene expression of these ATs by qPCR has shortlisted six putative ‘P-II-forming’ ATs. Further, six-frame translation, ab initio protein structure modelling and protein-ligand molecular docking of these ATs signified one MBOAT domain containing AT with preferential binding to the vanillic acid CoA thiol ester as well as with P-II., implying that this could be potential AT decorating final structure of P-II. ConclusionOrgan-wise comparative transcriptome mining coupled with reverse transcription real time qPCR and protein-ligand docking led to the identification of an acyltransferases, contributing to the final structure of P-II.

Chemical Constituents Isolated from the Leaves of Toricellia angulata Oliv. var. intermedia (Harms.) Hu

In our survey on the chemical composition of Chinese folk medicines, nine compounds were isolated from methanol extract of the leaves of Toricellia angulata Oliv. var. intermedia (Harms.) Hu (Corniaceae). The structures of these compounds were elucidated on the basis of NMR data analysis, which were identified as dimethyl 2-(hydroxymethyl)-5-oxocyclohexane-1,4-dicarboxylate (1), methyl succinate (2), 5-hydroxymethyl-2-furfuraldehyde (3), 7-hydroxy-6-methoxycoumarin (4), loliolide (5), (8 S)-deca-2-trans-2,9-diene-4,6-diyn-1,8-diol (6), methyl malate (7), griselinoside (8), and methyl linoleate (9), respectively. Among them, compound 1 is a new cyclohexanone derivative and given a trivial name torriangulate A, while others are categorized to be organic acids (2, 7, and 9), a coumarin derivative (4), a terpene lactone (5), a polyacetylene (6), and an iridoid glycoside (8). Compounds 3–5 were isolated from this genus for the first time and compound 9 was first identified from this species. The discovered compounds with novel or known structures further reveal the chemical basis of T. angulata var . intermedia, which lays a foundation for the development of T. angulata var . intermedia used as a traditionally folk medicine.

Cornel Iridoid Glycoside Ameliorated Alzheimer’s Disease-Like Pathologies and Necroptosis through RIPK1/MLKL Pathway in Young and Aged SAMP8 Mice

Background. Aging is an important risk factor for sporadic Alzheimer’s disease (AD) and other neurodegenerative diseases. Senescence-accelerated mouse-prone 8 (SAMP8) is used as an animal model for brain aging and sporadic AD research studies. The aim of the current study was to investigate the pharmacological effects of cornel iridoid glycoside (CIG), an active ingredient of Cornus officinalis, on AD-type pathological changes in young and aged SAMP8 mice. Methods. Locomotor activity test was used to detect the aging process of SAMP8 mice. Nissl staining and immunohistochemical staining were applied to detect neurons and myelin basic protein-labelled myelin sheath. Western blotting was used to detect the expression levels of related proteins of synapse, APP processing, and necroptosis. Results. The results showed that SAMP8 mice at the age of 6 and 14 months exhibited lower locomotor activity, age-related neuronal loss, demyelination, synaptic damage, and APP amyloidogenic processing. In addition, the increased levels of receptor-interacting protein kinase-1 (RIPK1), mixed lineage kinase domain-like protein (MLKL), and p-MLKL indicating necroptosis were found in the brain of SAMP8 mice. Intragastric administration of CIG for 2 months improved locomotor activity; alleviated neuronal loss and demyelination; increased the expression of synaptophysin, postsynaptic density protein 95, and AMPA receptor subunit 1; elevated the levels of soluble APPα fragment and disintegrin and metalloproteinase 10 (ADAM10); and decreased the levels of RIPK1, p-MLKL, and MLKL in the brain of young and aged SAMP8 mice. Conclusion. This study denoted that CIG might be a potential drug for aging-related neurodegenerative diseases such as AD.

Cornel Iridoid Glycoside Protects Against STAT1-Dependent Synapse and Memory Deficits by Increasing N-Methyl-D-aspartate Receptor Expression in a Tau Transgenic Mice

P301S transgenic mice are an animal model of tauopathy and Alzheimer’s disease (AD), exhibiting tau pathology and synaptic dysfunction. Cornel iridoid glycoside (CIG) is an active ingredient extracted from Cornus officinalis, a traditional Chinese herb. In the present study, the purpose was to investigate the effects and mechanisms of CIG on tau pathology and synaptic dysfunction using P301S transgenic mice. The results showed that intragastric administration of CIG for 3.5 months improved cognitive impairments and the survival rate of P301S mice. Electrophysiological recordings and transmission electron microscopy study showed that CIG improved synaptic plasticity and increased the ultrastructure and number of synapse. Moreover, CIG increased the expression levels of N-methyl-D-aspartate receptors (NMDAR) subunits GluN1, GluN2A, and GluN2B, and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) subunit GluA1. We inferred that the major mechanism of CIG involving in the regulation of synaptic dysfunctions was inhibiting the activation of Janus kinase-2 (JAK2)/signal transducer and activator of transcription 1 (STAT1) signaling pathway and alleviating STAT1-induced suppression of NMDAR expressions. Based on our findings, we thought CIG might be a promising candidate for the therapy of tauopathy such as AD.

Nine Unique Iridoids and Iridoid Glycosides From Patrinia scabiosaefolia

Patrinia scabiosaefolia is a medical and edible Chinese herb with high nutritional and medicinal value. The continuing study of its chemical constituents led to the discovery of nine unique iridoids and iridoid glycosides, including three new iridoids (1-3) and six previously unknown irioid glycosides (5-10), and one known compound (4). Among them, compound 1 was a deformed iridoid, while compounds 3, 5-7, and 10 formed a new ring in their skeletons which was uncommon in this genus. For compound 3, the new ring existed between C-3 and C-10, while a 1,3-dioxane appeared between C-7 and C-10 in compounds 5-7 and 10. Moreover, compound 10 was a bis-iridoid glycoside, which was the first reported in P. scabiosaefolia. And the sugar of irioid glycosides (5-10) was glucose at C-11, except in 9 which had a 5-deoxyglucose moiety. All their structures were confirmed based on the extensive spectroscopic analysis, including IR, UV, HR-ESI-MS, ECD, and 1D- and 2D-NMR experiments. Their cytotoxic activities against HL-60, A-549, SMMC-7721, MCF-7, SW480 were also tested.