HR LC-MS/MS metabolomic profiling of Yucca aloifolia fruit and the potential neuroprotective effect on rotenone-induced Parkinson's disease in rats

Yucca aloifolia L. fruit (Yucca or Spanish bayonet, family Asparagaceae) is recognized for its purplish red color reflecting its anthocyanin content, which has a powerful antioxidant activity. This study aimed to investigate yucca (YA) fruit extract's protective effect on Parkinson's disease (PD). In vitro study, the anti-inflammatory activity of yucca fruit extracts was explored by measuring tumor necrosis factor receptor 2 (TNF-R2) and nuclear factor kappa B (NF-KB) to choose the most effective extract. Afterward, a detailed in vivo investigation of the protective effect of the most active extract on rotenone-induced PD was performed on male albino Wister rats. First, the safety of the extract in two different doses (50 and 100 mg/kg in 0.9% saline orally) was confirmed by a toxicological study. The rats were divided into four groups: 1) normal control (NC); 2) rotenone group; and third and fourth groups received 50 and 100 mg/kg yucca extract, respectively. The neurobehavioral and locomotor activities of the rats were tested by rotarod, open field, and forced swim tests. Striatal dopamine, renal and liver functions, and oxidative stress markers were assessed. Western blot analysis of brain tissue samples was performed for p-AMPK, Wnt3a, and β-catenin. Histopathological examination of striatal tissue samples was performed by light and electron microscopy (EM). The metabolites of the active extract were characterized using high-resolution LC-MS/MS, and the results showed the prevalence of anthocyanins, saponins, phenolics, and choline. Biochemical and histopathological tests revealed a dose-dependent improvement with oral Yucca extract. The current study suggests a possible neuroprotective effect of the acidified 50% ethanol extract (YA-C) of the edible Yucca fruit, making it a promising therapeutic target for PD.

In silico and in vitro anti-inflammatory study of phenolic compounds isolated from Eucalyptus maculata resin

Plant resins are rich in bioactive compounds with high medicinal values. However, the chemistry and anti-inflammatory activity of the resins produced by trees of the genus Eucalyptus were scarcely investigated. The inflammatory targets cyclooxygenase-1 (COX-1), COX-2, TNF-, NF-B, and NO were significantly inhibited by the methanolic extract of Eucalyptus maculata kino resin (EME) and its CH₂Cl₂ soluble fraction (MCF). Sakuranetin (C1), (E)-cinnamic acid (C2), kaempferol 7- methyl ether (C3), 7-O-methyl aromadendrin (C4), and 1,6- dicinnamoyl-O-α-D-glucopyranoside (C5) were isolated from MCF. Three compounds (C1, C2, and C4) showed potent in vitro COX-1 inhibition, while C5 inhibited COX-2, TNF-α, NF-κB, and NO significantly. An in-silico study revealed that C5 had the highest binding affinity to the active site in COX-2 with binding energy score (S) of -14.85 kcal/mol, better than celecoxib (COX-2 inhibitor). In conclusion, 1,6-dicinnamoyl-O-α-D-glucopyranoside (C5) could be investigated further in the search for anti-inflammatory agents.

Gastroprotective and anti-Helicobacter pylori potentials of essential oils from the oleoresins of Araucaria bidwillii and Araucaria heterophylla

Plant resins or oleoresins comprise a chemically complex mixture of different classes of compounds. Oleoresin of the genus Araucaria combines essential oil (EO) and resin. It possesses gastroprotective, cytotoxic, and timicrobial, antipyretic, and anti-inflammatory activities. The study aimed to investigate the EOs from the oleoresins of two Araucaria species, A. bidwillii and A. heterophylla, chemically and biologically for their gastroprotective, anti-inflammatory, antioxidant, and anti-Helicobacter pylori potentials. The chemical composition of both species cultivated in Egypt was analyzed with GC-MS and compared with those cultivated abroad using principal component analysis (PCA). There were 37 and 17 secondary metabolites identified in A. heterophylla and A. bidwillii, respectively. The EOs of both species showed a pronounced inhibitory effect on Helicobacter pylori activity in vitro. The gastroprotective effect was assessed in vivo using ethanol-induced gastric ulcer model in rats. Inflammatory cytokines, oxidative stress, and the nuclear factor-kappa B (NF-κB) biomarkers were assessed in the stomach tissues. The ulcer index and percentage of ulcer protection were determined. Stomach sections were examined histopathologically by staining with (H/E) and periodic acid Schiff (PAS). Moreover, the proliferative index was determined using the Ki-67 immunostaining. The treatment of rats with EOs (50, 100, and 200 mg/kg, orally) 1 hour prior to ethanol administration showed promising gastroprotective, anti-inflammatory, and antioxidant potentials. These findings declared the gastroprotective role played by both EOs with the superiority of A. bidwillii over A. heterophylla via modulation of oxidative stress/NF-κB/inflammatory cytokines. Their use can be recommended to protect against the recurrence of peptic ulcers.

Russelioside B: a Pregnane Glycoside with Pharmacological Potential

Pregnanes and pregnane glycosides or their esters are well-studied secondary metabolites, many of them exhibit immunomodulator, anticancer, antidiabetic, antarthritic, antiulcer, anti-nociceptive, hypolipidemic, anti-inflammatory, and antibacterial properties. Pregnane glycosides are widely distributed in the families Apocyanaceae and Asclepiadaceae. Plant members of the genus Caralluma R.Br., Apocynaceae, are among the most studied species because of uses in traditional medicine or as food. They are a rich source of pregnane glycosides, as russelioside B. However, the bioactivity profile of this pregnane glycoside has not been reviewed until now. The present review aims to summarize the most important pharmacological and therapeutic applications of russelioside B with specific emphasis on the mechanism of actions associated with its administration in preclinical models. Russelioside B has many pharmacological effects including antidiabetic, anti-obesity, anti-nociceptive, antiulcer, anti-inflammatory, anti-arthritis effects, and antibiofilm, and wound healing activities. Despite its outstanding pharmacotherapeutic potential, russelioside B has never been tested in clinical trials. This review indicates that russelioside B is a potentially promising bioactive candidate, but further deeper mechanistic studies and clinical trials are needed in the future to elucidate its interaction with receptors of specific genes.