Chemical constituents from the whole herb of Hemiphragma heterophyllum

Natural products with potential hypoglycemic activity in T2DM: 2019-2023

As currently the most common metabolic disease, type 2 diabetes mellitus (T2DM) has shown a continuous increase in the number of patients in recent decades. Most anti-T2DM drugs tend to cause some side effects. Given the pathogenesis of T2DM, natural products have emerged as an important source of anti-T2DM drugs. This article reviews natural products with potential hypoglycemic activity from 2019 to 2023. A total of 200 previously natural products were discovered on SciFinder, PubMed and Web of Science. These products were categorized based on their structural frameworks and their biological activities were summarized. Although the mechanisms of action of most compounds are unclear, these compounds could still serve as candidates for the development of lead compounds. Therefore, further structure and activity research of natural products will significantly contribute to the development of potential anti-T2DM drugs.

Sesquilignans: Current research and potential prospective

Lignans are widely distributed in nature, primarily found in the xylem and resins of plants, with the constituent units C6-C3, and their dimers are the most common in plants. In recent years, the trimeric sesquilignans have also received increasing attention from scholars. More than 200 derivatives have been isolated and identified from nearly 50 families, most of which are different types (monoepoxy lignans, bisepoxy lignans, benzofuran lignans) connected with simple phenylpropanoids through ether bonds, C-C bonds, and oxygen-containing rings to constitute sesquilignans. Some of them also possess pharmacological properties, including antioxidants, hepatoprotectives, antitumors, anti-inflammatory properties, and other properties. In addition, the chemical structure of sesquilignans is closely related to the pharmacological activity, and chemical modification of methoxylation enhances the pharmacological activity. In contrast, phenolic hydroxyl and hydroxyl glycosides reduce the pharmacological activity. Therefore, the present review aims to summarize the chemical diversity, bioactivities, and constitutive relationships to provide a theoretical basis for the more profound development and utilization of sesquilignans.

The antinociceptive and anti-alpha-glucosidase effects of glucosides from Hemiphragma heterophyllum Wall

Hemiphragma heterophyllum Wall. is commonly used in traditional Yi herbal medicine for treating bellyache and toothache. In the current study, an unreported monoterpene glucoside, (S)-thymoquinol O-(6-O-oleuropeoyl)-β-d-glucopyranoside (1), together with 11 known glucosides were obtained from the whole herb of H. heterophyllum. Their structures were determined based on a detailed analysis of spectroscopic data and acid hydrolysis and methanolysis reactions. Bioassay results showed that compounds 1 and 10 at 40 mg/kg exhibited significant antinociceptive activity in the acetic acid-induced writhing model, with inhibitions of 59.80% and 64.07%, respectively. Moreover, five of the isolates showed moderate anti-α-glucosidase activities with IC50 values ranging from 5.67 to 46.16 μM.

Phenolic Fingerprinting and Bioactivity Profiling of Extracts and Isolated Compounds from Gypothamnium pinifolium Phil

Gypothamnium pinifolium Phil. (Asteraceae) is a small shrub that grows in the Paposo Valley of the II Antofagasta Region of Chile. This initial study is of the high-resolution phenolic fingerprinting, antioxidant activity, the relaxation effects in rat aorta, the inhibitory enzyme potential, plus the antiproliferative activity of the ethyl acetate and n-hexane extract from G. pinifolium and its two major isolated secondary metabolites (one coumarin: 2-nor-1,2-secolycoserone, and one diterpene: ent-labda-8,13-E-diene-15-ol). The study involves using ultra-high-performance liquid chromatography todiode array detection coupled with Q-Orbitrap mass spectrometry analysis (UHPLC-PDA-Orbi-trap-MS), in which various compounds were identified, including specific coumarins. The n-hexane extract showed total phenolic and flavonoid contents of 517.4 ± 12.5 mg GAE/100 g extract and 72.3 ± 3.7 mg QE/100 g extract, respectively. In addition, the antioxidant activity of the n-hexane extract was assessed using in-vitro assays such as bleaching of DPPH and ABTS (IC₅₀: 14.3 ± 0.52 and 2.51 ± 0.43 µg extract/mL, respectively), FRAP (347.12 ± 1.15 μmol Trolox equivalent/g extract), and ORAC (287.3 ± 1.54 μmol Trolox equivalents/g extract). Furthermore, the inhibition against cholinesterases (acetylcholinesterase (AChE) 4.58 ± 0.04 µg/mL, butyrylcholinesterase (BChE) IC₅₀: 23.44 ± 0.03 µg/mL) and tyrosinase (IC₅₀: 9.25 ± 0.15 µg/mL) enzymes of the n-hexane extract, and main compounds (IC₅₀: 1.21 ± 0.03 µg/mL, 11.23 ± 0.02 µg/mL, 3.23 ± 0.12 µg/mL, and 103.43 ± 16.86 µg/mL, correspondingly for the most active coumarin 1) were measured. The antiproliferative potential of the extracts and the two principal compounds against several solid human cancer cells was investigated. All of them showed good activity against cancer cells. Label-free live-cell imaging studies on HeLa cells exposed to the isolated coumarin and the diterpene enabled the observation of cell death and several apoptotic hallmarks. Our results indicate that G. pinifolium Phil. is a valuable source of secondary metabolites with potential activity against noncommunicable diseases.

Complete chloroplast genome of a widely distributed species in southwest China, Hemiphragma heterophyllum Wall. (Scrophulariaceae)

Hemiphragma heterophyllum Wall., a widely distributed species in southwest China, belongs to a monotypic genus, Hemiphragma Wall. in the Scrophulariaceae. To date, there has been no study on its complete chloroplast genome. Hence, we reported the first complete chloroplast genome sequence of H. heterophyllum here. The genome sequences of two individuals were extremely similar except slight differences on sequence lengths (152,707 bp and 152,700 bp, respectively). There was a typical circular quadripartite structure. A total of 113 genes were annotated, including 79 protein-coding genes, 29 tRNA genes, four rRNA genes, and one pseudogene. Among the annotated genes, 16 genes contained one intron, whereas another two genes (ycf3 and clpP) possessed two gene introns. Total GC content is 38.1% in the chloroplast genome. Moreover, a total of 63 simple sequence repeats (SSRs) with five types were detected. Phylogenetic analysis revealed that Hemiphragma was closely related to Veronica L. and Veronicastrum Heist. ex Farbic.