Tawfeek N et al. (2019) Molecules "Phenolic Compounds from Populus alba L. and Salix subserrata Willd. (Salicaceae) Counteract Oxidative Stress in Caenorhabditis elegans."

Roxo M, El-Shazly AM, Farrag N, Wink M, Tawfeek N, Sobeh M, Hamdan DI

[Molecules, 2019]

Utilizing bioassay- and TLC-guided column chromatography, fifteen secondary metabolites from <i>Populus alba</i> and eight compounds from <i>Salix subserrata</i> were isolated, including a novel plant metabolite salicyl ether and characterized using ultralviolet light (UV) absorbance, mass spectrometry (MS), ¹H-, ¹³C-NMR (nuclear magnetic resonance), heteronuclear single quantum coherence spectroscopy (HSQC) and heteronuclear multiple bond correlation (HMBC). The extracts, their sub-fractions and the isolated compounds exhibited promising antioxidant activities in vitro in DPPH and FRAP assays. Also, the extracts of <i>P. alba</i> leaf (PL), shoots (PS), and <i>S. subserrata</i> leaf (SL) demonstrated substantial antioxidant activities in vivo in the multicellular model organism <i>Caenorhabditis elegans</i>. For the first time, the isolated secondary metabolites, aromadendrin, tremuloidin, salicin, isorhamnetin-3-<i>O</i>--d-rutinoside, gallocatechin, triandrin, and chrysoeriol-7-<i>O</i>-glucuronide were investigated. They exhibited substantial antioxidant activities in vivo. Salicin, isorhamnetin-3-<i>O</i>--d-rutinoside and gallocatechin, in particular, protected the worms against a lethal dose of the pro-oxidant juglone (80 M), decreased the endogenous reactive oxygen species (ROS) level to 45.34%, 47.31%, 68.09% and reduced juglone- induced hsp-16.2::GFP (green fluorescence protein) expression to 79.62%, 70.17%, 26.77%, respectively. However, only gallocatechin induced higher levels of sod-3 expression. These findings support the traditional use of <i>Populus alba</i> and <i>Salix subserrata</i> for treating inflammation especially when ROS are involved.

Katiki LM et al. (2013) Vet Parasitol "Anthelmintic effect of plant extracts containing condensed and hydrolyzable tannins on Caenorhabditis elegans, and their antioxidant capacity."

Chagas AC, Lindsay DS, Zajac AM, Gonzalez JM, Amarante AF, Ferreira JF, Katiki LM

[Vet Parasitol, 2013]

Although tannin-rich forages are known to increase protein uptake and to reduce gastrointestinal nematode infections in grazing ruminants, most published research involves forages with condensed tannins (CT), while published literature lacks information on the anthelmintic capacity, nutritional benefits, and antioxidant capacity of alternative forages containing hydrolyzable tannins (HT). We evaluated the anthelmintic activity and the antioxidant capacity of plant extracts containing either mostly CT, mostly HT, or both CT and HT. Extracts were prepared with 70% acetone, lyophilized, redissolved to doses ranging from 1.0mg/mL to 25mg/mL, and tested against adult Caenorhabditis elegans as a test model. The extract concentrations that killed 50% (LC(50)) or 90% (LC(90)) of the nematodes in 24h were determined and compared to the veterinary anthelmintic levamisole (8 mg/mL). Extracts were quantified for CT by the acid butanol assay, for HT (based on gallic acid and ellagic acid) by high-performance liquid chromatography (HPLC) and total phenolics, and for their antioxidant activity by the oxygen radical absorbance capacity (ORAC) assay. Extracts with mostly CT were Lespedeza cuneata, Salix X sepulcralis, and Robinia pseudoacacia. Extracts rich in HT were Acer rubrum, Rosa multiflora, and Quercus alba, while Rhus typhina had both HT and CT. The extracts with the lowest LC(50) and LC(90) concentrations, respectively, in the C. elegans assay were Q. alba (0.75 and 1.06 mg/mL), R. typhina collected in 2007 (0.65 and 2.74 mg/mL), A. rubrum (1.03 and 5.54 mg/mL), and R. multiflora (2.14 and 8.70 mg/mL). At the doses of 20 and 25mg/mL, HT-rich, or both CT- and HT-rich, extracts were significantly more lethal to adult C. elegans than extracts containing only CT. All extracts were high in antioxidant capacity, with ORAC values ranging from 1800 moles to 4651 moles of trolox equivalents/g, but ORAC did not correlate with anthelmintic activity. The total phenolics test had a positive and highly significant (r=0.826, p 0.01) correlation with total hydrolyzable tannins. Plants used in this research are naturalized to the Appalachian edaphoclimatic conditions, but occur in temperate climate areas worldwide. They represent a rich, renewable, and unexplored source of tannins and antioxidants for grazing ruminants, whereas conventional CT-rich forages, such as L. cuneata, may be hard to establish and adapt to areas with temperate climate. Due to their high in vitro anthelmintic activity, antioxidant capacity, and their adaptability to non-arable lands, Q. alba, R. typhina, A. rubrum, and R. multiflora have a high potential to improve the health of grazing animals and must have their anthelmintic effects confirmed in vivo in both sheep and goats.

Sharma S et al. (2020) Mol Neurobiol "Wedelolactone Mitigates Parkinsonism Via Alleviating Oxidative Stress and Mitochondrial Dysfunction Through NRF2/SKN-1."

Trivedi M, Sharma S, Ranjan S, Pandey R, Pandey T, Trivedi S

[Mol Neurobiol, 2020]

Parkinsonism is an age-associated neurodegenerative disorder characterized by aggregation of -synuclein (-syn) protein in the substantia nigra region, degeneration of dopaminergic neurons, and deregulated lipid metabolism. Currently, only symptomatic relief has been provided by FDA-approved therapeutic approaches for Parkinson's disease (PD). The present study aims to evaluate the potential of wedelolactone (WDL), a natural occurring coumestan found in Eclipta alba to mitigate the parkinsonism in Caenorhabditis elegans disease model. In the present studies, supplementation with 37.5M WDL exhibited a reduction in the level of -syn in an age-dependent manner (22% at day 5, p&lt;0.05; and 16% at day 10, p&lt;0.001, n=30), along with improvement in neuronal health through basal movement, and elevated the dopamine levels evident through 1-nonanol repulsion results in wild-type and diseased worms. Moreover, WDL augmented the mitochondrial health in wild-type, PD-diseased, and mev-1 mutant worms that establish the inherent activity of WDL in the alleviation of oxidative stress. Furthermore, WDL supplementation significantly decreases the neutral lipid and triglyceride level and also alleviates protein carbonyl level in PD disease condition. The overall investigation will provide a pioneer to the future insights of PD research related to plant-based drugs. qPCR studies after WDL supplementation revealed alteration of genes involved in the regulation of various stress-responsive (sod-5, gst-4, skn-1), -syn-suppressing (lrk-1, ymel-1, lagr-1, grk-1), and mitochondrial (pink-1) genes. All together, these findings support that the WDL is a promising candidate to combat age-related multi-factorial PD pathology associated with protein misfolding and accumulation. The results provide sufficient information in the development of therapeutic medicines from natural products for improving the health.