Phytochemical Study of Aqueous Extract of Ochna schweinfurthiana F. Hoffm Powder Bark and Evaluation of Their Anti-Inflammatory, Cytotoxic, and Genotoxic Properties

Biflavonoid Methylchamaejasmin and Khaya grandifoliola Extract Inhibit NLRP3 Inflammasome in THP-1 Cell Model of Neuroinflammation

Neuroinflammation is a common hallmark of Alzheimer's disease (AD), with NLRP3 inflammasome proven to be activated in microglia of AD patients' brains. In this study, a newly isolated biflavonoid (7,7'-di-O-methylchamaejasmin/M8) and a crude extract of the plant Khaya grandifoliola (KG) were investigated for their inhibitory effect on inflammasome activation. In preliminary experiments, M8 and KG showed no cytotoxicity on human macrophage-like differentiated THP-1 cells and exhibited anti-inflammatory inhibition of nitric oxide produced following lipopolysaccharide stimulation. Furthermore, M8 and KG blocked IL-1β and IL-18 production by reducing NLRP3 inflammasome components including NFκB, NLRP3, Caspase-1, pro-IL-1β, and pro-IL-18 at the mRNA and protein levels. Regarding the formation of ASC (apoptosis-associated speck-like protein containing a CARD) specks during inflammasome activation, the size and fluorescent intensity of the existing specks were unchanged across all treatment conditions. However, M8 and KG treatments were shown to prevent further speck formation. In addition, experiments on amyloid β phagocytosis showed that M8 and KG pretreatments can restore the phagocytic activity of THP-1 cells, which was impaired following inflammasome activation. Altogether, our findings describe for the first time a promising role of biflavonoids and KG extract in preventing inflammasome activation and protecting against neuroinflammation, a key factor in AD development.

Ethnomedicinal Information on Plants Used for the Treatment of Bone Fractures, Wounds, and Sprains in the Northern Region of the Republic of Benin

Medicinal plants are frequently used in African countries due to their importance in the treatment of various conditions. In the northern Republic of Benin, traditional healers are recognized as specialists in the treatment of fractures, wounds, and sprains. The present study was conducted to document the practices (diagnosis and materials) and traditional knowledge accumulated by healers in this region on their area of specialty. In addition, literature-based research was performed to support the usage of the most cited plants. Sixty traditional healers identified as "reference persons" from Atakora and Donga departments in the northern Republic of Benin, who specialized in the treatment of fractures, wounds, and sprains, were interviewed in their communities through a semi-structured questionnaire. Information about the practice, age of the healers, medicinal plants used in this treatment, methods of preparation, and administration were collected. Samples of the plant species were also collected, identified, and stored in the national herbarium at the University of Abomey-Calavi, the Republic of Benin. The study enabled the identification of thirty-four (34) species belonging to twenty-three (23) families. Ochna rhizomatosa and Ochna schweinfurthiana (21%) were the most quoted plants among the species, followed by Chasmanthera dependens (12.1%), Piliostigma thonningii (11.3%), and Combretum sericeum (8.1%). These plants were reported to strengthen bones, reduce inflammation, relieve pain, and promote healing in the northern part of the Republic of Benin. Besides their ability to treat fractures, wounds, and sprains, they are also used for multiple purposes in the West African subregions. According to the available literature, some of the plants will need to be investigated for their phytoconstituents and pharmacological activity to validate their ethnobotanical uses. These results confirm the need for documenting traditional knowledge since it represents an opportunity for exploring plant species with potentially good pharmacological effects, which have been barely investigated. Plants identified may constitute a significant source of bioactive compounds in the treatment of various ailments such as skin inflammation and musculoskeletal disorders. They can be further explored to justify their use in traditional Beninese medicine.

Chemical Fingerprinting, Antioxidant, and Anti-Inflammatory Potential of Hydroethanolic Extract of Trigonella foenum-graecum

In the current study, the antioxidant and anti-inflammatory potential of hydroethanolic extract of T. foenum-graecum seeds was evaluated. Phenolic profiling of T. foenum-graecum was conducted through high-performance liquid chromatography-photodiode array (HPLC-PDA) as well as through the mass spectrometry technique to characterize compounds responsible for bioactivity, which confirmed almost 18 compounds, 13 of which were quantified through a chromatographic assay. In vitro antioxidant analysis of the extract exhibited substantial antioxidant activities with the lowest IC50 value of both DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) inhibition assays. The extract was found to be non-toxic against human RBCs and murine macrophage RAW 264.7 cells. Moreover, the extract significantly (p < 0.001) reduced the lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-α), intrlukin-6 (IL-6), prostaglandin E2 (PGE2), and nitric oxide (NO) in RAW 264.7 cells in a concentration-dependent manner. The hydroethanolic extract of T. foenum-graecum exhibited considerable anti-inflammatory potential by decreasing the cellular infiltration to the inflammatory site in both carrageenan-induced peritonitis and an air pouch model of inflammation. Pretreatment with T. foenum-graecum extract caused significant improvement in antioxidants such as superoxide dismutase (SOD), CAT (catalase), malondialdehyde (MDA), and myeloperoxidase (MPO) against oxidative stress induced by carrageenan. Based on our results of in vivo and in vitro experimentation, we concluded that hydroethanolic extract of T. foenum-graecum is a potential source of phenolic compounds with antioxidant and anti-inflammatory potential.

Therapeutic Potential of Selected Medicinal Plants Against Carrageenan Induced Inflammation in Rats

The current study was aimed to analyze the therapeutic effect of selected medicinal plants, that is, Curcuma longa, Zingiber officinale, Trigonella graceum-foenum, Nigella sativa, and Syzygium aromaticum against carrageenan-induced oxidative stress and inflammation in rats. Phytochemical analysis revealed the presence of diverse range of bioactives. IC₅₀ values for antioxidant assays including DPPH (2,2-diphenyl-1-picrylhydrazyl), metal chelating, ABTS scavenging (2, 2^′-Azino-Bis-3-Ethylbenzothiazoline-6-Sulfonic Acid), β-carotene bleaching, and H₂O₂ (hydrogen peroxide) scavenging ranged from 37-294, 71-243.4, 69.66-191.8, 98.92-228.5, and 82-234.9 μg/mL, respectively. All tested plants extract were found active against tested pathogenic microorganisms with lowest minimum inhibitory concentrations. Oral administration of tested plants extracts in different doses (250, 500, and 1000 mg/kg b. w) did not exhibit any toxicological effects on hemato-biochemical profile of treated rats in comparison to control group rats. Further, plants extract exhibited considerable anti-inflammatory activity in rats paw inflammation and decreased cellular infiltration to inflammatory site in dose dependent manner. Pretreatment of animals with tested plants extract (100, 200, and 400 mg/kg b. w.) caused significant alteration in total antioxidants, oxidants, and enzymes activities in paw tissue homogenate and the effect was more pronounced at higher concentration (400 mg/kg b. w.). Results showed that tested plants extract are rich source of diverse classes of phenolics and have therapeutic potential against oxidative stress and inflammation.

Evaluation of acute oral toxicity, embryotoxicity and cytotoxicity of the polar fraction of Parkinsonia aculeata aerial parts extract

Ethnopharmacobotanical information reports that Parkinsonia aculeata infusion is used to control diabetes-related complications and dyslipidemia. However, few studies are reported on the safe use of this species. The aim of this study is to evaluate the acute toxicity, embryotoxicity and cytotoxicity of a polar fraction obtained from hydroethanolic extract of P. aculeata (PfrHEPA). For the acute toxicity test, we considered the Up and Down method which the guidelines are described by the Organization for Economic Cooperation and Development (OECD N°425). The animals were treated with PfrHEPA (2000 mg/kg) or with distilled water (10 ml/kg) by gavage and observed from Day 1 to14. For embryotoxicity assay, zebrafish embryos were exposed to PfrHEPA (100 mg/L) and toxicity parameters were observed during four consecutive days. The cytotoxicity of PfrHEPA (5, 10, 25, 50, 75 and 100 μg/ml, respectively) was performed on normal cell lines (mesenchymal stem cells, African green monkey renal cells and mouse pre-adipocytes 3 T3-L1 using the MTT salt reduction assay. In the acute toxicity test, no mortality was observed in mice treated with PfrHEPA (2000 mg/kg), as well as behavioral changes, histopathological abnormalities and hematological and biochemical variables. In the embryotoxicity test, no abnormal changes related to the toxicological parameters were observed in the period of 96 h. Regarding the cytotoxicity assay, PfrHEPA showed no cytotoxic effect on the normal cell lines tested, with an IC₅₀ value > 100 μg/ml. These results suggest the safe use of P. aculeata, however, more trials are needed for PfrHEPA to be presented as new safe therapeutic proposal for the control of metabolic disorders.