[Research progress in targeting DNA G-quadruplexes using natural products].

DNA G-quadruplex(G4) is a guanine-rich single-stranded DNA sequence that spontaneously folds into a spherical four-stranded DNA secondary structure in oncogene promoter sequences and telomeres. G4s are highly associated with the occurrence and development of cancer and have emerged as promising anticancer targets. Natural products have long been important sources of anticancer drug development. In recent years, significant progress has been made in the discovery of natural drugs targeting DNA G4s, with many DNA G4s have been confirmed as promising targets of natural products, including MYC-G4, KRAS-G4, PDGFR-ß-G4, BCL-2-G4, VEGF-G4, and telomeric G4. This review summarizes the research progress in discovering natural small molecules that target DNA G4s and their binding mechanisms. It also discusses the opportunities of and challenges in developing drugs targeting DNA G4s. This review will serve as a valuable reference for the research on natural products, particularly in the development of novel antitumor medications.

[Three new cucurbitane-type triterpenoid glycosides from Citrullus colocynthis and their anti-inflammatory activity].

Three new cucurbitane-type triterpenoid glycosides were separated from the ethyl acetate extract of Citrullus colocynthis by a variety of chromatographic techniques. According to the data of NMR, HR-ESI-MS, and/or comparison with the reported data, the three novel cucurbitane-type triterpenoid glycosides were identified as colocynthenin E(1), colocynthenin G(2), and colocynthenin H(3). The cell inflammation model was established with RAW264.7 macrophages exposed to lipopolysaccharide and then used to determine the anti-inflammatory activities of the three compounds. Compounds 2 and 3 showed mild anti-inflammatory activities with the IC_(50) of 48.21 and 40.11 µmol·L~(-1), respectively, compared with that(IC_(50)=7.57 µmol·L~(-1)) of the positive control dexamethasone.

[Recent Progress on Pharmaceutical Properties of Extracellular Vesicles from Mesenchymal Stem Cells--Review].

Mesenchymal stem cells (MSCs) have been officially approved in many countries to treat graft-versus-host disease, autoimmune disorders and those associated with tissue regeneration after hematopoietic stem cell transplantation. Studies in recent years have confirmed that MSC acts mainly through paracrine mechanism, in which extracellular vesicles secreted by MSC (MSC-EV) play a central role. MSC-EV has overwhelming advantages over MSC itself in the setting of adverse effects in clinical application, indicating that MSC-EV might take the place of its parent cells to be a potentially therapeutic tool for "cell-free therapy". The pharmaceutical properties of MSC-EV largely depend upon the practical and optimal techniques including large-scale expansion of MSC, the modification of MSC based on the indications and the in vivo dynamic features of MSC-EV, and the methods for preparing and harvesting large amounts of MSC-EV. The recent progresses on the issues above will be briefly reviewed.

[Research progress on chemical constituents of Citrullus colocynthis and their pharmacological effects].

Citrullus colocynthis is widely distributed in the desert regions of the world. C. colocynthis has shown to improve constipation, liver diseases, jaundice, typhoid fever, diabetes and asthma in traditional use. As a kind of exterritorialy medicinal material, C. colocynthis has been used in China and introduced successfully. The main active ingredients of C. colocynthis are cucurbitacin, flavonoids, alkaloids and phenolic acids, which have been proven to have antioxidant, anti-diabetic, anti-pathogenic microorganisms and anti-cancer activities in modern pharmacological research. This paper reviews the traditional application, chemical composition and pharmacological effects of C. colocynthis, and provides reference for the in-depth study for the efficacy and mechanism of different components of C. colocynthis.

[Research progress of chemical constituents and biological activities of essential oil of Pistacia lentiscus].

Pistacia lentiscus,which belongs to foreign medicine resources,is widely distributed in the Mediterranean and Middle Eastern area. The essential oils are a mixture of several volatile compounds mainly monoterpenes and sesquiterpenes obtained from different parts of P. lentiscus by hydrodistillation. The variability of chemical composition,biological activities and content of essential oil is strongly affected by extraction technology,environmental and sex factors. It is indicated that essential oils of P. lentiscus have kinds of biological activities such as antibacterial,anticancer,anti-atherogenesis,antioxidant,anti-inflammatory and insecticidal activities.Many scholars hold the opinion that combination of different components with synergistic and/or additive actions should account for their biological activities. Due to its diverse efficacy and special taste,the essential oil of P. lentiscus has been extensively used in medicine,food and cosmetics industries. A mini review of chemical constituents and biological activities of essential oil of P. lentiscus in the past20 years is made here to provide valuable reference for the construction of " the Belt and Road".

[Chemical constituents from traditional Uighur herbal medicine Elaeagnus angustifolia flowers].

Seven aromatic glycosides (1-7), including four phenylethanol glycosides, one phenylmethanol glycoside, one phenylpropane glycoside and one benzoside, were isolated from the methanolic extract of Uighur Medicine Elaeagnus angustifolia flowers. Their structures were elucidated based on the analysis of spectroscopic data (1D, 2D NMR and HR-MS). Compound 1 is a new compound, named as angustifol A. Six known compounds were identified as 2-phenylethyl-O-ß-D-glucopyranoside(2), salidroside (3), vanillic acid 4-O-ß-D-glucopyranoside(4), vanilloloside (5), (Z)-isoconiferin (6), 2-phenylethyl-6-O-α-L-arabinofuranosyl-ß-D-glucopyranoside (7). Compounds 2-7 were isolated from the genus Elaeagnus for the first time. In vitro anti-inflammatory assays revealed that none of these compounds showed good COX inhibitory activities.

An electron-transfer photochromic crystalline MOF accompanying photoswitchable luminescence in a host-guest system.

A new electron transfer type photoactive host-guest supramolecule was constructed by introducing (CH3)2NH2+ cations to the MOF framework. The resulting compound 1 exhibits reversible photochromic property without using photochromic components, resulting from photoinduced electron-transfer between the electron-rich anionic framework and the electron-deficient guest ions. In addition, a photoluminescence "on/off switch" occurs during the coloration-decoloration process. The raw materials are non-poisonous and harmless, hence compound 1 may be more cost-effective, clean, and harmless to the heath than existing photochromic materials.