A new pair of enantiomeric lignans from the fruits of Morinda citrifolia and their absolute configuration

New furofuran and tetrahydrofuran lignans from the flower buds of Magnolia biondii Pamp and their antiallergic effects

The dried flower buds of Magnolia biondii Pamp (herbal name, Xin-Yi) are a traditional Chinese medicine with a long history of clinical use in the treatment of allergic rhinitis and sinusitis. However, the constituents responsible for its antiallergic effects remain clearly unidentified. In the present study, totally 33 lignans were obtained from M. biondii. Among them, two novel furofuran lignans (1 and 2), two novel tetrahydrofuran lignans (3 and 4), and other 16 known lignans were isolated first time from M. biondii. The antiallergic effects of compounds 1-33 on mouse bone marrow-derived mast cells (BMMCs) degrunaliton were evaluated and results showed that compounds 7, 8, 13, 15 and 18 could significantly inhibited β-hex release on BMMCs. The results proved that furofuran and tetrahydrofuran lignans were the main constituents in M. biondii and their antiallergic effects were related with suppressing mast cell activation.

Natural Enantiomers: Occurrence, Biogenesis and Biological Properties

The knowledge that natural products (NPs) are potent and selective modulators of important biomacromolecules (e.g., DNA and proteins) has inspired some of the world's most successful pharmaceuticals and agrochemicals. Notwithstanding these successes and despite a growing number of reports on naturally occurring pairs of enantiomers, this area of NP science still remains largely unexplored, consistent with the adage "If you don't seek, you don't find". Statistically, a rapidly growing number of enantiomeric NPs have been reported in the last several years. The current review provides a comprehensive overview of recent records on natural enantiomers, with the aim of advancing awareness and providing a better understanding of the chemical diversity and biogenetic context, as well as the biological properties and therapeutic (drug discovery) potential, of enantiomeric NPs.

Ptehoosines A and B: Two new sesamin-type sesquilignans with antiangiogenic activity from Pterocephalus hookeri (C.B. Clarke) Höeck

Two undescribed sesamin-type sesquilignans ptehoosines A (1) and B (2), together with 4 known lignans (3-6), were isolated from Pterocephalus hookeri (C.B. Clarke) Höeck which was widely used as traditional Tibetan medicine for treatment of rheumatoid arthritis. Their structures were determined by HR-ESI-MS, NMR analysis and CD experiment. The in vitro antiangiogenic effect of all isolated compounds against human umbilical vein endothelial cells (HUVECs) were evaluated by CCK-8 assay. Among them, compound 1 exhibited significant proliferative inhibition on HUVECs with IC₅₀ value of 32.82 ± 0.99 μM. Further in vitro study indicated 1 could arrest cell cycle at G0/G1 phase and reduce the migration of HUVECs. In vivo experiment exhibited 1 could inhibit tail vessels plexus in zebrafish. The above finding suggested that 1 was a promising lead compound against RA by inhibiting of angiogenesis.

A new 7',9-epoxylignan from the stems of Salacia chinensis

Bioactivity-guided isolation of the CHCl₃-soluble fraction of the stems of Salacia chinensis L. (Celastraceae) was carried out to obtain a new 7',9-epoxylignan (1) and three 7,9':7',9-diepoxylignans (2-4). The absolute configuration of 1 was elucidated based on NMR and ECD spectroscopic data interpretation. All isolated lignans showed intermediate α-glucosidase inhibitory activity with the IC₅₀ values ranging from 28.5 to 85.6 µM.

DNA or Protein Methylation-Dependent Regulation of Activator Protein-1 Function

Epigenetic regulation and modification govern the transcriptional mechanisms that promote disease initiation and progression, but can also control the oncogenic processes, cell signaling networks, immunogenicity, and immune cells involved in anti-inflammatory and anti-tumor responses. The study of epigenetic mechanisms could have important implications for the development of potential anti-inflammatory treatments and anti-cancer immunotherapies. In this review, we have described the key role of epigenetic progression: DNA methylation, histone methylation or modification, and protein methylation, with an emphasis on the activator protein-1 (AP-1) signaling pathway. Transcription factor AP-1 regulates multiple genes and is involved in diverse cellular processes, including survival, differentiation, apoptosis, and development. Here, the AP-1 regulatory mechanism by DNA, histone, or protein methylation was also reviewed. Various methyltransferases activate or suppress AP-1 activities in diverse ways. We summarize the current studies on epigenetic alterations, which regulate AP-1 signaling during inflammation, cancer, and autoimmune diseases, and discuss the epigenetic mechanisms involved in the regulation of AP-1 signaling.

Two new lignans from Zanthoxylum armatum

Zanthoxylum armatum, its peels possessed better special flavour, as well as various bioactivities, such as anti-inflammatory, anti-microbial and anti-tumour. In our chemical investigation on the peels of Z. armatum, two new lignans (1 and 2) and three known lignans (3-5) were isolated by silica gel column chromatography, ODS column and preparative HPLC and their structures were established as zanthlignans A and B (1-2), (-)-asarinin (3), phylligenin (4) and planispine A (5) through various spectroscopic techniques including UV, IR, HR-ESI-MS, NMR and CD methods.

Indian Morinda species: A review

Morinda is a largest genus of Rubiaceae family, and its 11 species are found in India. In India, plant species are known by several common names as great morinda, Indian mulberry, noni, beach mulberry and cheese fruit. Various Morinda products (capsules, tablets, skin products and fruit juices) are available in the market, used by people for treatment of several health complaints. A diversity of phytochemicals including iridoids, flavonoids, flavonoid glycosides, anthraquinones, coumarins, lignanas, noniosides, phenolics and triterpenoids have been reported from Morinda species. Morinda species are used in the treatment of inflammation, cancer, diabetes, psyquiatric disorders, and bacterial and viral infections. The noni fruit juice (Morinda citrifolia) and its products are used clinically in the treatment of cancer, hypertension and cervical spondylosis affecting patients. M. citrifolia fuit juice, with different doses, is used in the maintaining blood pressure and reducing of superoxides, HDL and LDL levels. Similarly, oligosaccharide capsules and tablets of root extract of M. officinalis are recommended as medicine for the treatment of kidney problems and sexual dysfunctions of patients. The toxicological studies revealed that higher doses of fruit juice (4,000 or 5,000 mg/kg) of M. citrifolia for 2 or more months cause toxic effects on liver and kidneys. M. officinalis root extracts (ethanolic and aqueous) are found fully safe during treatment of diseases. A large number of reviews are available on M. citrifolia but very few studies are conducted on other Indian Morinda species. This review reports the comprehensive knowledge on state-wise distribution, botany, ethnomedicinal uses, phytochemistry, pharmacological activities, clinical applications and toxicological evaluations of 11 species of Morinda found in India.

Recovery of Sesamin, Sesamolin, and Minor Lignans From Sesame Oil Using Solid Support-Free Liquid-Liquid Extraction and Chromatography Techniques and Evaluation of Their Enzymatic Inhibition Properties

In this study, an integrated process for the recovery of sesamin and sesamolin, two high added-value lignans of sesame oil (SO) was developed, using synchronous extraction and chromatography techniques. The extraction of SO phenolic content was studied using two different extraction techniques: Annular centrifugal extraction (ACE) and centrifugal partition extraction (CPE). The derived data of each experiment were compared in terms of revealing the yields, time, and solvents consumption showing that CPE is the most effective technique, concerning the solvent consumption. The isolation of lignans was achieved using centrifugal partition chromatography (CPC) both on semi-preparative and preparative scale. The biphasic system used for this purpose consisted of the following solvents: n-Hex/EtOAc/EtOH/H₂O in proportion 2:3:3:2 (v/v/v/v) and direct recovery of the two major lignans sesamin and sesamolin was achieved. In parallel the CPC analysis resulted in the isolation of four minor lignans of sesame oil, i.e., samin, sesamol, sesaminol, and episesaminol. Structure elucidation of isolated lignans was based on HRMS/MS and NMR experiments. High-performance liquid chromatography (HPLC) was employed for quantitative analysis of the obtained extracts to determine the purity of the isolated compounds as well. The results of this study demonstrated that sesamin and sesamolin were recovered in purity higher than 95%, verifying the effectiveness of the purposed separation methodology. Finally, due to the general application of sesame oil in cosmetic industry, all the pure compounds were evaluated for their tyrosinase, elastase, collagenase, and hyaluronidase inhibition activity.

Lignans and Neolignans: Plant secondary metabolites as a reservoir of biologically active substances

Lignans and neolignans are plant secondary metabolites derived from the oxidative coupling of phenylpropanoids. Biological activity of these phenolic compounds ranges from antioxidant, antitumor (terminaloside P, IC₅₀ = 10 nM), anti-inflammatory, anti-neurodegenerative (schibitubin B, IC₅₀ = 3.2 nM) and antiviral (patentiflorin A, IC₅₀ = 14-23 nM) to antimicrobial. In addition, it was observed that several members of this group, namely enterolactone and its biochemical precursors also known as phytoestrogens, possess important protective properties. Most of these lignans and neolignans are presented in reasonable amounts in one's diet and thus the protection they provide against the colon and breast cancer, to name a few, is even more important to note. Similarly, neuroprotective properties were observed (schisanwilsonin G, IC₅₀ = 3.2 nM) These structural motives also serve as an important starting point in the development of anticancer drugs. Presumably the most famous members of this family, etoposide and teniposide, synthetic derivatives of podophyllotoxin, are used in the clinical treatment of lymphocytic leukemia, certain brain tumors, and lung tumors already for nearly 20 years. This review describes 413 lignans and neolignans which have been isolated between 2016 and mid-2018 being reported in more than 300 peer-reviewed articles. It covers their source, structure elucidation, and bioactivity. Within the review, the structure-based overview of compounds as well as the bioactivity-based overview of compounds are described.

Naturally Lignan-Rich Foods: A Dietary Tool for Health Promotion?

Dietary guidelines universally advise adherence to plant-based diets. Plant-based foods confer considerable health benefits, partly attributable to their abundant micronutrient (e.g., polyphenol) content. Interest in polyphenols is largely focused on the contribution of their antioxidant activity to the prevention of various disorders, including cardiovascular disease and cancer. Polyphenols are classified into groups, such as stilbenes, flavonoids, phenolic acids, lignans and others. Lignans, which possess a steroid-like chemical structure and are defined as phytoestrogens, are of particular interest to researchers. Traditionally, health benefits attributed to lignans have included a lowered risk of heart disease, menopausal symptoms, osteoporosis and breast cancer. However, the intake of naturally lignan-rich foods varies with the type of diet. Consequently, based on the latest humans' findings and gathered information on lignan-rich foods collected from Phenol Explorer database this review focuses on the potential health benefits attributable to the consumption of different diets containing naturally lignan-rich foods. Current evidence highlight the bioactive properties of lignans as human health-promoting molecules. Thus, dietary intake of lignan-rich foods could be a useful way to bolster the prevention of chronic illness, such as certain types of cancers and cardiovascular disease.

Morinda citrifolia noni water extract enhances innate and adaptive immune responses in healthy mice, ex vivo, and in vitro

Although Morinda citrifolia (noni) has long been used in traditional medicines for human diseases, its molecular and cellular mechanism of immunostimulatory ability to improve human health under normal healthy conditions is not fully elucidated. This study aimed to investigate the in vitro and in vivo immunostimulatory activity of M. citrifolia fruit water extract treated with enzymes (Mc-eWE). In vitro studies revealed that Mc-eWE stimulated the cells by inducing nitric oxide (NO) production and the expression of inflammatory cytokines, such as interleukin (IL)-1β, IL-6, IL-12, tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ). The immunostimulatory activity was mediated by activation of NF-κB and AP-1. Ex vivo studies showed that Mc-eWE stimulated splenocytes isolated from mice by inducing NO production and expression of immunostimulatory cytokines and by downregulating the expression of the immunosuppressive cytokine IL-10 without cytotoxicity. In vivo demonstrated that Mc-eWE induced immunostimulation by modulating populations of splenic immune cells, especially by increasing the population of IFN-γ⁺ NK cells. Mc-eWE enhanced the expression of inflammatory genes and immunostimulatory cytokines and inhibited the expression of IL-10 in the mouse splenocytes and sera. Taken together, these results suggest that Mc-eWE plays an immunostimulatory role by activating innate and adaptive immune responses.