Linderanidins A-F: Rare oligomeric flavonoids with an unusual C-3-C-4 linkage from the roots of Lindera erythrocarpa and their inhibitory activities on autophagy.

Autophagy is a crucial process for maintaining cellular homeostasis by degrading and recycling unnecessary or damaged cellular components. In the process of exploring autophagy regulators in plants, unique nine oligomeric flavonoids linked by the bonding of C-3 and C-4, consisting of three pairs of biflavonoids, linderanidins A-C [(+)-1/(-)-1, (+)-2/(-)-2, and (+)-3/(-)-3], and three trimeric A-type proanthocyanidins, linderanidins D-F (4-6), were isolated from the roots of Lindera erythrocarpa. The structures and absolute configurations of these compounds were determined using various techniques, such as 1D and 2D NMR, mass spectrometry, X-ray crystallography, and electronic circular dichroism. All isolates were evaluated for their ability to regulate autophagy, and compounds (±)-1-(±)-3, (-)-1-(-)-3, (+)-1-(+)-3 and 4 were found to inhibit autophagy by blocking the fusion process between autophagosome and lysosome in HEK293 cells. This study suggests that unique oligomeric flavonoids possessing a C-3-C-4 linkage derived from the roots of L. erythrocarpa are potent autophagy inhibitors.

Scientometric assessment of scientific documents published in 2020 on herbal medicines used for COVID-19.

Objective: Many studies have suggested herbal medicines as alternatives or adjuvants to modern drugs for COVID-19. Their scientometric analyses can provide a scientific overview of this topic. Materials and methods: Web of Science (WOS) and Scopus were searched for articles on the use of herbal medicines in COVID-19 published until 26 October 2020. Collected data were analyzed for document type, subject area, top journal, citation number, and authors' collaboration network using VOSviewer 1.6.15, ScientoPy 2.0.3, Gephi 0.9.2, and SPSS 15 statistical tools. Results: After screening the 3185 retrieved records, 378 and 849 records, respectively from WOS and Scopus, remained for quantity analysis. Original and review articles were the two main types of papers in both databases. Top subject areas were drug and medicine, respectively in the WOS and Scopus databases. The top three productive countries in the field were China, the US, and India. The most cited article was a practice guideline in both databases. "Journal of Biomolecular Structure Dynamics" in WOS and "Chinese Traditional and Herbal Drugs" in Scopus were the top journals. Top keywords included "COVID-19″ and "Traditional Chinese Medicine". US authors had the highest collaboration with other authors. Conclusions: The current study provides a snapshot of the quantity and characteristics of published scholarly documents in recent months in the intersection of herbal medicines and COVID-19. Our findings help scientists to find the existing gaps, identify the active authors and scientific institutes to collaborate with and use their experience to produce new knowledge in the future.

Medicinal plants and their isolated phytochemicals for the management of chemotherapy-induced neuropathy: therapeutic targets and clinical perspective.

BACKGROUND: Chemotherapy, as one of the main approaches of cancer treatment, is accompanied with several adverse effects, including chemotherapy-induced peripheral neuropathy (CIPN). Since current methods to control the condition are not completely effective, new treatment options should be introduced. Medicinal plants can be suitable candidates to be assessed regarding their effects in CIPN. Current paper reviews the available preclinical and clinical studies on the efficacy of herbal medicines in CIPN. METHODS: Electronic databases including PubMed, Scopus, and Cochrane library were searched with the keywords "neuropathy" in the title/abstract and "plant", "extract", or "herb" in the whole text. Data were collected from inception until April 2018. RESULTS: Plants such as chamomile (Matricaria chamomilla L.), sage (Salvia officinalis L.), cinnamon (Cinnamomum cassia (L.) D. Don), and sweet flag (Acorus calamus L.) as well as phytochemicals like matrine, curcumin, and thioctic acid have demonstrated beneficial effects in animal models of CIPN via prevention of axonal degeneration, decrease in total calcium level, improvement of endogenous antioxidant defense mechanisms such as superoxide dismutase and reduced glutathione, and regulation of neural cell apoptosis, nuclear factor-ĸB, cyclooxygenase-2, and nitric oxide signaling. Also, five clinical trials have evaluated the effect of herbal products in patients with CIPN. CONCLUSIONS: There are currently limited clinical evidence on medicinal plants for CIPN which shows the necessity of future mechanistic studies, as well as well-designed clinical trial for further confirmation of the safety and efficacy of herbal medicines in CIPN. Graphical abstract Schematic mechanisms of medicinal plants to prevent chemotherapy-induced neuropathy: NO: nitric oxide, TNF: tumor necrosis factor, PG: prostaglandin, NF-ĸB: nuclear factor kappa B, LPO: lipid peroxidation, ROS: reactive oxygen species, COX: cyclooxygenase, IL: interleukin, ERK: extracellular signal-related kinase, X: inhibition, ↓: induction.

Medicinal plants for gingivitis: a review of clinical trials.

OBJECTIVES: Periodontal diseases are among prevalent oral health problems which may ultimately lead to severe complications in oral cavity. Herbal products can be designed as single or multicomponent preparations for better oral health. This study aims to review current clinical trials on the effectiveness of herbal products in gingivitis. MATERIALS AND METHODS: Electronic databases, including PubMed, Scopus, ScienceDirect and Cochrane library were searched with the keywords "gingivitis" in the title/abstract and "plant/ extract/ herb" in the whole text for clinical trials on herbal treatments for gingivitis. Data were collected from 2000 until January 2018. Only papers with English full-texts were included in our study. RESULTS: Herbal medicines in the form of dentifrice, mouth rinse, gel, and gum were assessed in gingivitis via specific indices including plaque index, bleeding index, microbial count, and biomarkers of inflammation. Pomegranate, aloe, green tea, and miswak have a large body of evidence supporting their effectiveness in gingivitis. They could act via several mechanisms such as decrease in gingival inflammation and bleeding, inhibition of dental plaque formation, and improvement in different indices of oral hygiene. Some polyherbal formulations such as triphala were also significantly effective in managing gingivitis complications. CONCLUSION: Our study supports the efficacy and safety of several medicinal plants for gingivitis; however, some plants do not have enough evidence due to the few number of clinical trials. Thus, future studies are mandatory for further confirmation of the efficacy of these medicinal plants.