Secoiridoid glycosides from the fruits of Ligustrum lucidum and their in vitro anti-inflammatory activity

Seven new secoiridoid glycosides (1-7), together with a known analogue (8), were isolated from the fruits of Ligustrum lucidum. Their structures with absolute configurations were determined by HR-ESI-MS, 1D and 2D NMR, and electronic circular dichroism (ECD) spectroscopic analysis, as well as biogenetic consideration. Compounds 1 and 2 are the first examples of secoiridoid glycoside dimers featuring a rare rearranged oleoside-type secoiridoid moiety, and compounds 3-7 represent a new class of oleoside-type secoiridoid glycosides with unusual stereochemistry at C-1 position. A plausible biosynthetic pathway for this group of unusual secoiridoid glycosides was also proposed herein. In addition, the isolates were evaluated for their in vitro anti-inflammatory activity, and all tested compounds exhibited modest inhibitory effects against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages.

Ligustri Lucidi Fructus, a traditional Chinese Medicine: Comprehensive review of botany, traditional uses, chemical composition, pharmacology, and toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Ligustri Lucidi Fructus (LLF) is one of the usual Chinese herbs that has long been used with high therapeutic and condition value. LLF is used for the treatment of dizziness and tinnitus, soreness and weakness of the waist and knees, premature greying of the hair, the darkness of the eyes, internal heat and thirst, bone steam and hot flashes and other symptoms.

AIM OF THE STUDY

This review reviews botany, traditional uses, processing, phytochemistry, quality control, pharmacology, toxicity and pharmacokinetics to better understand its therapeutic potential.

MATERIALS AND METHODS

The literature on LLF was obtained from Google Scholar and Baidu Scholar, PubMed, ScienceDirect, SciFinder, Web of Science, China National Knowledge Infrastructure (CNKI), WAN FANG DATA and libraries. Some local books, official websites, PhD or MS's dissertations were also included. Phytochemical constituents' structures were drawn by ChemDraw software.

RESULTS

So far, Multiple chemical components were isolated and identified from LLF, mainly including terpenoids and flavonoids. Modern studies have shown that LLF extracts and compounds have a wide range of pharmacological effects, including antitumor, liver protection, blood glucose, lipid-lowering, immune regulation, and other aspects.

CONCLUSIONS

LLF occupies an important position in the traditional medical system. It is cost-effective and is a significant plant with therapeutic applications in modern medicine. However, further in-depth studies are needed to determine the medical use of this plant and its chemical composition, pharmacological activity, quality control, toxicity and pharmacokinetics.

Isolation of bioactive limonoids from the fruits of Melia azedarach

Two previously undescribed limonoids, 1-O-benzoyl-3-O-deactylnimbolinin C (1) and a pair of epimers named toosendalactonins A and B (12a and 12b), together with ten known compounds (2-11) were isolated from the fruits of Melia azedarach L. Their structures were determined by extensive spectroscopic methods, including 1D-, 2D-nuclear magnetic resonance, and mass spectrometry. All the isolated compounds were evaluated for their nitric oxide (NO) inhibition in lipopolysaccharide-activated microglia and nerve growth factor (NGF) production in astrocytes. Compounds 1-2 and 5-8 significantly inhibited NO production, which is comparable to the positive control, L-NMMA. Previously undescribed limonoid, compound 12, and two known limonoids, munronin K (3) and 12-O-methyl-1-O-deacetyl-nimbolinin B (4), showed the highest potency to increase the NGF production in C6 astrocytes. [Formula: see text].

Hydroxyoleoside-type seco-iridoids from Symplocos cochinchinensis and their insulin mimetic activity

As part of an ongoing study of new insulin mimetic agents from medicinal plants, the 70% EtOH extract of Symplocos cochinchinensis was found to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. The intensive targeted isolation of this active extract resulted in ten new hydroxyoleoside-type compounds conjugated with a phenolic acid and monoterpene (1–6 and 8–11), as well as four known compounds (7 and 12–14). The chemical structures of the new compounds were determined based on spectroscopic data analysis (¹H and ¹³C NMR, HSQC, HMBC, NOESY and MS). The absolute configurations of the isolated compounds were determined by electronic circular dichroism (ECD) analysis of derivatives obtained after a series of reactions, such as those with dirhodium (ІІ) tetrakis (trifluoroacetate) and dimolybdenum (ІІ) tetraacetate. In vitro, compounds 3, 7 and 8 moderately increased the 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-D-glucose (2-NBDG) uptake level in differentiated 3T3-L1 adipocytes. For further studies, we evaluated their effects on the expression of glucose transporter-4 (GLUT4), its translocation, protein tyrosine phosphatase 1B (PTP1B) inhibition and expression of phosphorylated Akt. Our results strongly suggest that the traditional uses of this plant can be described as active constituents by hydroxyoleoside-type compounds.

Hydroxycinnamoyl derivatives and secoiridoid glycoside derivatives from Syringa vulgaris flowers and their effects on the pro-inflammatory responses of human neutrophils

Thirteen new compounds including caffeoyl-glucaric and p-coumaroyl-altraric acid derivatives, one monoterpenoid glucoside, four secoiridoid glycosides, and three hydroxycinnamoyl phenylpropanoid glycosides esterified with an oleoside 11-methyl ester along with fifteen known compounds were isolated from flowers of Syringa vulgaris L. (Oleaceae). Their structures were elucidated by high-resolution spectroscopic methods. The tested compounds were able to decrease the production of reactive oxygen species. Moreover, oleoechinacoside (13), demethylhydroxyoleonuezhenide (14), demethyloleonuezhenide (15), syringaoleoacteoside (25) and oleoacteoside (26) at the concentration of 50μM, moderately suppressed the LPS-stimulated release of pro-inflammatory chemokine IL-8 and TNF-α from human neutrophils. Moreover, oleonuezhenide (12), oleoside 11-methyl ester (16) and oleoacteoside (26) at the concentration of 50μM were able to induce the surface expression of interleukin 10 receptor, which is suppressed by the incubation of monocyte/macrophage cells with LPS.

Ligustrum lucidum and its Constituents: A Mini-Review on the Anti-Osteoporosis Potential

Osteoporosis is a metabolic bone disorder commonly occurred in aging populations, particularly postmenopausal women and patients who undergo long-term steroid or anti-estrogen therapies. Given the rapid growth of the aging population, the prevalence of bone loss, and the huge medical and healthcare cost involved, demand for alternative approaches for the promotion of bone health is pressing. With the advent of global interest in complementary and alternative medicine and natural products, Chinese medicine serves as a viable source that offers benefits to improve and maintain bone health. This review summarizes the scientific information on the Chinese medicinal herb Ligustrum lucidum and its chemical components as potential therapy for osteoporosis.