Antioxidant Phenylpropanoid Glycosides from Ginkgo biloba Fruit and Identification of a New Phenylpropanoid Glycoside, Ginkgopanoside

Laricitrin 3-Rutinoside from Ginkgo biloba Fruits Prevents Damage in TNF-α-Stimulated Normal Human Dermal Fibroblasts

Human skin comprises the epidermis and dermis, which perform interactive functional activities with each other in order to maintain the skin's tensile strength. In particular, the dermal layer is crucial for skin protection. However, skin aging destroys collagen and elastin fibers, causing wrinkles, pigments, and sagging. Skin aging-related factors, such as tumor necrosis factor-α (TNF-α), promote the generation of intercellular reactive oxygen species (ROS). These are known to stimulate the hypersecretion of matrix metalloproteinase-1 (MMP-1), which degrades collagen and inhibits collagen synthesis. In this study, as part of our ongoing discovery of natural products, we investigated potential natural products derived from ginkgo fruit (Ginkgo biloba fruit) with protective effects against TNF-α-induced skin aging. Phytochemical investigation of the MeOH extract of G. biloba fruits, aided by liquid chromatography-mass spectrometry, led to the isolation of 14 compounds (1-14) from the n-butanol-soluble fraction. These were structurally determined to be: (E)-coniferin (1), syringin (2), 4-hydroxybenzoic acid 4-O-β-D-glucopyranoside (3), vanillic acid 4-O-β-D-glucopyranoside (4), glucosyringic acid (5), (E)-ferulic acid 4-O-β-D-glucoside (6), (E)-sinapic acid 4-O-β-D-glucopyranoside (7), ginkgotoxin-5-glucoside (8), ginkgopanoside (9), (Z)-4-coumaric acid 4-O-β-D-glucopyranoside (10), (1'R,2'S,5'R,8'S,2'Z,4'E)-dihydrophaseic acid 3'-O-β-D-glucopyranoside (11), eucomic acid (12), rutin (13), and laricitrin 3-rutinoside (L3R) (14). Biological evaluation of the isolated compounds for their effects on intracellular ROS generation showed that, of these 14 compounds, L3R (14) inhibited TNF-α-stimulated ROS generation (p < 0.001 at 100 μM). Inhibition of ROS generation by L3R led to the suppression of MMP-1 secretion and protection against collagen degradation. The inhibitory effect of L3R was mediated by the inhibition of extracellular signal regulated kinase (ERK) phosphorylation. Furthermore, L3R diminished the secretion of pro-inflammatory cytokines interleukin 6 (IL-6) and interleukin 8 (IL-8). Based on these experimental results, L3R is a potential bioactive natural product that can be used to protect against skin damage, including aging, in cosmetics and pharmaceuticals.

TiO2-Nanowired Delivery of Chinese Extract of Ginkgo biloba EGb-761 and Bilobalide BN-52021 Enhanced Neuroprotective Effects of Cerebrolysin Following Spinal Cord Injury at Cold Environment

Military personnel during combat or peacekeeping operations are exposed to extreme climates of hot or cold environments for longer durations. Spinal cord injury is quite common in military personnel following central nervous system (CNS) trauma indicating a possibility of altered pathophysiological responses at different ambient temperatures. Our previous studies show that the pathophysiology of brain injury is exacerbated in animals acclimated to cold (5 °C) or hot (30 °C) environments. In these diverse ambient temperature zones, trauma exacerbated oxidative stress generation inducing greater blood-brain barrier (BBB) permeability and cell damage. Extracts of Ginkgo biloba EGb-761 and BN-52021 treatment reduces brain pathology following heat stress. This effect is further improved following TiO₂ nanowired delivery in heat stress in animal models. Several studies indicate the role of EGb-761 in attenuating spinal cord induced neuronal damages and improved functional deficit. This is quite likely that these effects are further improved following nanowired delivery of EGb-761 and BN-52021 with cerebrolysin-a balanced composition of several neurotrophic factors and peptide fragments in spinal cord trauma. In this review, TiO₂ nanowired delivery of EGb-761 and BN-52021 with nanowired cerebrolysin is examined in a rat model of spinal cord injury at cold environment. Our results show that spinal cord injury aggravates cord pathology in cold-acclimated rats and nanowired delivery of EGb-761 and BN-52021 with cerebrolysin significantly induced superior neuroprotection, not reported earlier.

Can Extracts from the Leaves and Fruits of the Cotoneaster Species Be Considered Promising Anti-Acne Agents?

This study aimed to evaluate the phenolic profile and biological activity of the extracts from the leaves and fruits of Cotoneaster nebrodensis and Cotoneaster roseus. Considering that miscellaneous species of Cotoneaster are thought to be healing in traditional Asian medicine, we assumed that this uninvestigated species may reveal significant therapeutic properties. Here, we report the simultaneous assessment of chemical composition as well as biological activities (antioxidant, anti-inflammatory, antibacterial, and cytotoxic properties) of tested species. Complementary LC-MS analysis revealed that polyphenols (especially flavonoids and proanthocyanidins) are the overriding phytochemicals with the greatest significance in tested biological activities. In vitro chemical tests considering biological activities revealed that obtained results showed different values depending on concentration, extraction solvent as well as phenolic content. Biological assays demonstrated that the investigated extracts possessed antibacterial properties and were not cytotoxic toward normal skin fibroblasts. Given the obtained results, we concluded that knowledge of the chemical composition and biological activities of investigated species are important to achieve a better understanding of the utilization of these plants in traditional medicine and be useful for further research in their application to treat various diseases, such as skin disorders.

New phenalenone derivatives from the Hawaiian volcanic soil-associated fungus Penicillium herquei FT729 and their inhibitory effects on indoleamine 2,3-dioxygenase 1 (IDO1)

Phenalenone derivatives sourced from fungi are polyketides that have attracted significant interest because of their diverse chemical structures and potential bioactivities. As part of our ongoing quest to discover novel natural products with biological properties from diverse natural resources, three unreported phenalenone derivatives (1-3), named ent-12-methoxyisoherqueinone (1), (-)-scleroamide (2), and (+)-scleroamide (3), together with four known phenalenone derivatives, ent-atrovenetinone (4), isoherqueinone (5), herqueinone (6), and ent-peniciherquinone (7) were isolated from the Hawaiian soil fungus Penicillium herquei FT729, collected on the Big Island, Hawaii. Compounds 2 and 3 were enantiomers, which were separated using a chiral-phase HPLC column, which provided optically pure compounds 2 and 3. The structures of the novel compounds were established by extensive spectroscopic analyses, including 1D and 2D NMR and high-resolution ESIMS. Their absolute configurations were determined using quantum chemical electronic circular dichroism (ECD) calculations. The inhibitory activity of the isolated compounds (1-7) against indoleamine 2,3-dioxygenase 1 (IDO1) was assessed. Compounds 1, 5-7 inhibited IDO1, with IC₅₀ values of 32.59, 36.86, 19.05, and 24.18 μM, respectively. These findings demonstrated that the phenalenone derivatives 1 and 5-7, as IDO1 inhibitors, are promising anticancer immunotherapeutic agents.