Solanrubiellin A, a hydroanthraquinone dimer with antibacterial and cytotoxic activity from Solanum lyratum

The interaction of anti-inflammatory and anti-tumor components in the traditional Chinese medicine Solanum lyratum Thunb

Solanum lyratum Thunb is a traditional Chinese medicinal with a significant clinical outcome for tumor treatment; however, chemicals or fractions separated from the herb did not exhibit strong and comparable efficacy. To investigate the potential synergy or antagonism among chemicals in the extract, we obtained the compounds solavetivone (SO), tigogenin (TI) and friedelin (FR) from the herb. The anti-tumor effects of these three monomer compounds alone or in combination with the anti-inflammatory compound DRG were also tested in this study. SO, FR and TI used alone did not inhibit the proliferation of A549 and HepG2 cells, but the combination of the three achieved 40% inhibition. In vitro anti-inflammatory analysis showed that DRG had a stronger anti-inflammatory effect than TS at the same concentration, and the combination of DRG with SO, FR or TI inhibited the anti-tumor effect of DRG. This is the first study that documented the synergistic and antagonistic interactions between different compounds in a single herb.

Research progress on chemical components and pharmacological action of Solanum lyratum Thunb

OBJECTIVES

Solanum lyratum Thunb (SLT) is a perennial plant of the Solanaceae family, and is extensively used in the clinical practice of traditional Chinese medicine. Malaria, oedema, gonorrhoea, cancer, wind and fever, jaundiced hepatitis, cholecystitis and rheumatoid arthritis are among the diseases that it is used to treat. To offer a foundation for further development and usage of SLT, the pieces of literature about the chemical composition and pharmacological action of SLT were reviewed and analysed.

KEY FINDINGS

The chemical constituents of SLT mainly included steroids, alkaloids, flavonoids, terpenoids, anthraquinones, phenylpropanoids and others. Pharmacological action mainly contains anti-tumour, antibacterial, anti-inflammatory, anti-oxidation and other pharmacological actions, among them, the anti-tumour effect is particularly outstanding.

SUMMARY

At present, studies on the pharmacological effects of SLT mainly focus on alkaloids and steroidal saponins. In the follow-up studies, studies on the pharmacological activities of other chemical components in SLT, such as flavonoids and terpenoids, should be strengthened. It has the potential to pave the way for more research and development of novel SLT medicines.

Phytochemical and pharmacological studies on Solanum lyratum: a review

Solanum lyratum is one of the temperate plants, broadly distributed in Korea, China, Japan, India, and South-East Asia and well-documented in those oriental ethnic medicine systems for curing cancers, jaundice, edema, gonorrhea, cholecystitis, phlogosis, rheumatoid arthritis, etc. This review systematically summarized the research progress on S. lyratum respecting the botany, traditional uses, phytochemistry, pharmacology, and toxicology to increase people's in-depth understanding of this plant, by data retrieval in a series of online or off-line electronic databases as far as we can reach. Steroidal saponins and alkaloids, terpenoids, nitrogenous compounds, and flavonoid compounds are the main chemical constituents in S. lyratum. Among them, steroidal alkaloids and saponins are the major active ingredients ever found in S. lyratum, exerting activities of anti-cancer, anti-inflammation, anti-microbial, anti-allergy, and anti-oxidation in vivo or in vitro. As a result, S. lyratum has been frequently prescribed for the abovementioned therapeutic purposes, and there are substantial traditional and modern shreds of evidence of its use.

Toxicological Safety Evaluation in Acute and 21-Day Studies of Ethanol Extract from Solanum lyratum Thunb

Solanum lyratum (Solanaceae) is a traditional Chinese medicine widely used to remedy cold fever, damp-heat jaundice, herpes, and nephritis dropsy. Despite its obvious therapeutic advantages, few toxicological studies have involved the efficacy and safety of its long-term treatment. To investigate the acute and subchronic toxicity of the extract of 75% ethanol extract of whole Solanum lyratum (ESL) after oral administration in mice. In acute toxicity experiment, mice were intragastric administration with ESL at doses of 1000, 2000, 3000, 4000, or 5000 mg/kg for 1 day. In a subchronic toxicity experiment, mice were intragastrically administration with ESL at doses of 180, 360, and 720 mg/kg and 0.9% saline for 21 days. Weight gain, hematological, biochemical, and histopathological analysis of vital organs were evaluated. The presence of aristolochic acid I in ESL was studied using UPLC-QTOF-MS. Phytochemical analysis indicated that the presence of aristolochic acid I in ESL was 0.0025 mg/g. This relatively low concentration is not enough to cause toxicity. In the acute toxicity experiment, neither mortality nor clinical alterations were shown, except for the mild transient diarrhea at 5000 mg/kg. So the LD₅₀ value of ESL was assessed to be more than 5000 mg/kg. In the subchronic toxicity experiment, neither mortality nor treatment-related clinical signs were observed. There was a significant increase in body weight, hemoglobin (HB), and urea nitrogen (BUN) after administration with ESL at 180 mg/kg. In addition, the weight of the stomach was increased and the hematocrit (HCT) was decreased after administration with ESL at 360 mg/kg. The changes were not considered treatment-related toxicological effects because the toxicity and histopathological analysis indicate that the extracts are safe for oral administration.

Antibacterial sesquiterpenoids from Solanum lyratum

Investigation into the chemical diversity of Solanum lyratum led to the discovery of one new sesquiterpenoid, solyraterpenoid A (1), and two known compounds (2 and 3). The structure incorporating absolute configuration of 1 was determined via spectroscopic data, mainly including HRESIMS and NMR, and single-crystal X-ray diffraction analysis. Compound 1 showed significant antibacterial activity against Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae with MIC values of 8, 8, and 4 μg/mL, respectively.

The Health Benefits of Emodin, a Natural Anthraquinone Derived from Rhubarb-A Summary Update

Emodin (6-methyl-1,3,8-trihydroxyanthraquinone) is a naturally occurring anthraquinone derivative found in roots and leaves of various plants, fungi and lichens. For a long time it has been used in traditional Chinese medicine as an active ingredient in herbs. Among other sources, it is isolated from the rhubarb Rheum palmatum or tuber fleece-flower Polygonam multiflorum. Emodin has a wide range of biological activities, including diuretic, antibacterial, antiulcer, anti-inflammatory, anticancer and antinociceptive. According to the most recent studies, emodin acts as an antimalarial and antiallergic agent, and can also reverse resistance to chemotherapy. In the present work the potential therapeutic role of emodin in treatment of inflammatory diseases, cancers and microbial infections is analysed.

Total Synthesis of (+)-Rubellin C

The rubellins are a family of stereochemically complex anthraquinoid heterodimers containing an unprecedented chemical scaffold. Although the rubellins have been known for over three decades, no total synthesis has been achieved since their discovery. Their topology is characterized by a 6-5-6 fused ring system, five neighboring stereocenters including a quaternary center all in a convoluted core, and an anthraquinone nucleus. The rubellin architecture has been shown to inhibit and reverse the aggregation of tau protein, a therapeutically relevant target for Alzheimer's disease. Herein, we describe the first stereoselective synthesis of a member of the family, (+)-rubellin C, in 16 steps. Strategic disconnections allow expedient construction of stereochemical and topological intricacy in a short sequence of borylative and transition metal-catalyzed steps.

Recent progress of antibacterial natural products: Future antibiotics candidates

The discovery of novel antibacterial molecules plays a key role in solving the current antibiotic crisis issue. Natural products have long been an important source of drug discovery. Herein, we reviewed 256 natural products from 11 structural classes in the period of 2016-01/2020, which were selected by SciFinder with new compounds or new structures and MICs lower than 10 μg/mL or 10 μM as criterions. This review will provide some effective antibacterial lead compounds for medicinal chemists, which will promote the antibiotics research based on natural products to the next level.