Strigolactones can be a potential tool to fight environmental stresses in arid lands.

BACKGROUND: Environmental stresses pose a significant threat to plant growth and ecosystem productivity, particularly in arid lands that are more susceptible to climate change. Strigolactones (SLs), carotenoid-derived plant hormones, have emerged as a potential tool for mitigating environmental stresses. METHODS: This review aimed to gather information on SLs' role in enhancing plant tolerance to ecological stresses and their possible use in improving the resistance mechanisms of arid land plant species to intense aridity in the face of climate change. RESULTS: Roots exude SLs under different environmental stresses, including macronutrient deficiency, especially phosphorus (P), which facilitates a symbiotic association with arbuscular mycorrhiza fungi (AMF). SLs, in association with AMF, improve root system architecture, nutrient acquisition, water uptake, stomatal conductance, antioxidant mechanisms, morphological traits, and overall stress tolerance in plants. Transcriptomic analysis revealed that SL-mediated acclimatization to abiotic stresses involves multiple hormonal pathways, including abscisic acid (ABA), cytokinins (CK), gibberellic acid (GA), and auxin. However, most of the experiments have been conducted on crops, and little attention has been paid to the dominant vegetation in arid lands that plays a crucial role in reducing soil erosion, desertification, and land degradation. All the environmental gradients (nutrient starvation, drought, salinity, and temperature) that trigger SL biosynthesis/exudation prevail in arid regions. The above-mentioned functions of SLs can potentially be used to improve vegetation restoration and sustainable agriculture. CONCLUSIONS: Present review concluded that knowledge on SL-mediated tolerance in plants is developed, but still in-depth research is needed on downstream signaling components in plants, SL molecular mechanisms and physiological interactions, efficient methods of synthetic SLs production, and their effective application in field conditions. This review also invites researchers to explore the possible application of SLs in improving the survival rate of indigenous vegetation in arid lands, which can potentially help combat land degradation problems.

Steroidal alkaloids from the bulbs of Fritillaria pallidiflora Schrenk and their anti-inflammatory activity.

Steroidal alkaloids (1-11), including one new 24-hydroxylated cevanine-type steroidal alkaloid, named yibeinone F (1), were isolated from the bulbs of Fritillaria pallidiflora Schrenk. Their structures were elucidated by analyses of extensive spectroscopic data and comparison of the NMR data with those reported previously, and the structures of compounds 1, 7 and 11 were further confirmed by X-ray single crystal diffraction analyses. The anti-inflammatory effects of all the isolated alkaloids were evaluated in LPS-activated RAW264.7 macrophages. Among them, compounds 9 (stenanzine) and 10 (hapepunine) showed significant inhibitory effects against LPS-induced NO production with IC50 values of 8.04 µM and 20.85 µM, respectively. Furthermore, compound 9 effectively inhibited the release of cytokines such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and prostaglandin E2 (PGE2), and suppressed the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2) in LPS-stimulated RAW264.7 cells. Further experiments revealed the underlying mechanism that 9 blocked LPS-induced phosphorylation and degradation of inhibitor-α of nuclear transcription factor κB (IκBα) and c-Jun N-terminal kinase (JNK) in RAW264.7 cells. Taken together, compound 9 may be a valuable candidate for the treatment of inflammatory diseases.

Ferroptosis inhibitory constituents from the fruits of Cullen corylifolium.

In current study, we studied the phytochemicals of Cullen corylifolium (fruits) in which we identify twenty compounds, including two coumarins (1 and 2), three coumestans (3-5), fourchalcone (6-9), three dihydroflavones (10-12), four isoflavones (13-16), one flavonoid (17) and three meroterpenes (18-20). Among these, compounds 4, 5 and 12 were isolated from C. corylifolium for the first time. The ferroptosis inhibitory effects of the isolated phytochemicals were assessed using erastin-exposed HT22 mouse hippocampal cells. Compounds 3 and 18 showed the most potent inhibition with the IC50 values of 5.21 µM and 5.41 µM, respectively. Moreover, molecular docking study showed that compound 3 possessed tremendous inhibitory affinity for human 5-lipoxygenase (5-LOX) and Kelch-like ECH-related protein 1: nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) protein-protein interactions, two important ferroptosis-related targets. These findings indicate that compound 3 (psoralidin) may be a potential therapeutic agent for the treatment of ferroptosis-related diseases.

Terpenoid and phenolic derivatives from the aerial parts of Elsholtzia rugulosa and their anti-inflammatory activity.

Seven undescribed terpenoids, including three pairs of enantiomers, named (±)-rugulolides A-C, and one cyclopentenone derivative, named rugulolide D, together with twenty-six known compounds, were isolated from the aerial parts of Elsholtzia rugulosa. The chiral separation of rugulolides A-C was achieved by high-performance liquid chromatography using the chiral column. Their structures were elucidated unambiguously based on comprehensive spectroscopic analysis in conjunction with electronic circular dichroism (ECD) and single-crystal X-ray diffraction experiments. Rugulolides A-D are rare naturally occurring terpenoid derivatives featuring a methylated α,ß-unsaturated-γ-lactone or a cyclopent-2-en-1-one nucleus. All the isolates were evaluated for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 cell, among them, four compounds showed moderate inhibition with IC50 values ranging from 12.46 to 23.10 µM.

Two new triterpenoid saponins derived from the leaves of Panax ginseng and their antiinflammatory activity.

BACKGROUND: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. METHODS: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. RESULTS AND CONCLUSIONS: Two novel, minor triterpenoid saponins, ginsenoside LS1 (1) and 5,6-didehydroginsenoside Rg3 (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with IC50 of 37.38 µM compared with that of NG-monomethyl-L-arginine (IC50 = 90.76 µM). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin E2 and tumor necrosis factor-α. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.

Two New Cucurbitane Glycosides from the Fruits of Siraitia grosvenori.

Two novel cucurbitane glycosides, named as 11-oxomogroside III A1 and 7ß-methoxy-mogroside V, along with sixteen known ones were isolated from the fruits of Siraitia grosvenori SWINGLE. The structures of the new compounds were characterized by chemical and extensive spectral methods.

Senkyunolide H protects against MPP+-induced apoptosis via the ROS-mediated mitogen-activated protein kinase pathway in PC12 cells.

Senkyunolide H (SNH) is a phthalide isolated from the rhizome of Ligusticum chuanxiong Hort. that has been reported to have several pharmacological activities, including anti-atherosclerotic, antiproliferative, and cytoprotective effects. In this study, we investigated the neuroprotective effects and potential mechanisms of SNH against 1-methyl-4-phenylpyridinium (MPP+)-induced oxidative stress. We demonstrated that SNH pretreatment significantly attenuated MPP+-induced neurotoxicity and apoptosis in PC12 cells. In addition, SNH attenuated the effect of MPP+ on the expression of the pro-apoptotic factors Bax and caspase-3. Meanwhile, SNH prevented oxidative stress by reducing reactive oxygen species generation, mitochondrial membrane potential loss, cytochrome C release, and malondialdehyde levels while increasing antioxidant enzyme activity (e.g., superoxide dismutase, catalase, and glutathione peroxidase). In addition, SNH inhibited nuclear accumulation of nuclear factor-κB and c-Jun N-terminal kinase and phosphorylation p38 mitogen-activated protein kinases (MAPKs). Overall, this investigation provides novel evidence that SNH exerts neuroprotective effects via the ROS-mediated MAPK pathway and represents a potential preventive or therapeutic agent for neuronal disorders.