The aqueous extract from Toona sinensis leaves inhibits microglia-mediated neuroinflammation

Low-Temperature Regulates the Cell Structure and Chlorophyll in Addition to Cellulose Metabolism of Postharvest Red Toona sinensis Buds across Different Seasons

Postharvest fibrosis and greening of Toona sinensis buds significantly affect their quality during storage. This study aimed to clarify the effects of low-temperature storage on postharvest red TSB quality harvested in different seasons. Red TSB samples were collected from Guizhou province, China, 21 days after the beginning of spring (Lichun), summer (Lixia), and autumn (Liqiu), and stored at 4 °C in dark conditions. We compared and analyzed the appearance, microstructure, chlorophyll and cellulose content, and expression levels of related genes across different seasons. The results indicated that TSB harvested in spring had a bright, purple-red color, whereas those harvested in summer and autumn were green. All samples lost water and darkened after 1 day of storage. Severe greening occurred in spring-harvested TSB within 3 days, a phenomenon not observed in summer and autumn samples. Microstructural analysis revealed that the cells in the palisade and spongy tissues of spring and autumn TSB settled closely during storage, while summer TSB cells remained loosely aligned. Xylem cells were smallest in spring-harvested TSB and largest in autumn. Prolonged storage led to thickening of the secondary cell walls and pith cell autolysis in the petioles, enlarging the cavity area. Chlorophyll content was higher in leaves than in petioles, while cellulose content was lower in petioles across all seasons. Both chlorophyll and cellulose content increased with storage time. Gene expression analysis showed season-dependent variations and significant increases in the expression of over half of the chlorophyll-related and cellulose-related genes during refrigeration, correlating with the observed changes in chlorophyll and cellulose content. This research provides valuable insights for improving postharvest storage and freshness preservation strategies for red TSB across different seasons.

Traditional Uses, Chemical Constituents and Pharmacological Activities of the Toona sinensis Plant

Toona sinensis (A. Juss.) Roem., which is widely distributed in China, is a homologous plant resource of medicine and food. The leaves, seeds, barks, buds and pericarps of T. sinensis can be used as medicine with traditional efficacy. Due to its extensive use in traditional medicine in the ancient world, the T. sinensis plant has significant development potential. In this review, 206 compounds, including triterpenoids (1-133), sesquiterpenoids (134-135), diterpenoids (136-142), sterols (143-147), phenols (148-167), flavonoids (168-186), phenylpropanoids (187-192) and others (193-206), are isolated from the T. sinensis plant. The mass spectrum cracking laws of representative compounds (64, 128, 129, 154-156, 175, 177, 179 and 183) are reviewed, which are conducive to the discovery of novel active substances. Modern pharmacological studies have shown that T. sinensis extracts and their compounds have antidiabetic, antidiabetic nephropathy, antioxidant, anti-inflammatory, antitumor, hepatoprotective, antiviral, antibacterial, immunopotentiation and other biological activities. The traditional uses, chemical constituents, compound cracking laws and pharmacological activities of different parts of T. sinensis are reviewed, laying the foundation for improving the development and utilization of its medicinal value.

Physicochemical properties and solution conformation of polysaccharides from Toona sinensis (A. Juss) Roem leaves

In this study, two polysaccharide fractions (TSP-1 and TSP-2) were isolated from Toona sinensis leaves. The physicochemical properties and solution conformations of TSP-1 and TSP-2 were investigated. DSC and TG results showed that TSP-1 and TSP-2 had thermal stability. The intrinsic viscosities of TSP-1 and TSP-2 solutions were 11.42 and 6.13 mL/g, respectively. Rheological results showed that the viscosities of TSP-1 and TSP-2 solutions were affected by polysaccharide concentration, Ca2+ and extreme pH. Furthermore, TSP-1 exhibited a weak gel behavior at the concentrations of 0.5 %-2.0 %, while TSP-2 showed a weak gel behavior at the concentration of 2 %. HPSEC-MALLS analysis revealed that the Rg values of TSP-1 and TSP-2 were 96.8 nm and 56.2 nm, respectively. Conformation analysis indicated that TSP-1 behaved as a sphere, while TSP-2 behaved like a rigid rod. These results suggest that TSP-1 and TSP-2 can be used as additives in food, pharmaceutical and cosmetic industries.

Integrated volatilomic profiles and chemometrics provide new insights into the spatial distribution and aroma differences of volatile compounds in seven Toona sinensis cultivars

As a popular vegetable, the unique and pleasant aroma is the key quality characteristic of Toona sinensis. To explore the sources and differences of aroma, the volatilomic profiling in the leaves and shoots of seven T. sinensis cultivars were investigated by chemometric analysis. The results indicated that aroma differences of each cultivar can be distinguished by W5S, W1S, W1W and W2S sensors during E-nose analysis. More than two thirds of all volatile organic compounds (VOCs) were derived from the leaves of most cultivars, except for Ximu toon. Notably, 2-mercapto-3,4-dimethyl-2,3-dihydrothiophene, 3,4-dimethyl thiophene, methyl thiirane, isocaryophyllene and hexanal were the major VOCs in both the leaves and shoots of T. sinensis. By constructing a weighted correlation network model, 5 modules and 11 hub VOCs were identified in the leaf samples of all cultivars. The data indicate that differential intracellular metabolic responses are responsible for the aroma formation of seven T. sinensis cultivars.

Moringa oleifera modulates cholinergic and purinergic enzymes activity in BV-2 microglial cells

Microglia are immune cells that are resident in central nervous system. Activation of microglial cells are detrimental to the survival of neurons. Thus, prevention of microglia activation and/or protection against microglia activation could be potential therapeutic strategy towards the management of inflammation-mediated neurodegenerative diseases. Moringa oleifera is widely consumed as food and used in folklore medicine for treating several diseases. This study was convened to investigate the effect of aqueous extract of Moringa oleifera on cell viability, cholinergic and purinergic enzymes in BV-2 microglial cultured cell. Aqueous extract of Moringa oleifera was prepared, lyophilized and reconstituted in 0.5% dimethylsulphoxide (DMSO). Cells were treated with Moringa oleifera extracts (0.1-100 μg/mL) and assessed for cell viability and nitric oxide production. Furthermore, the effect of Moringa oleifera on enzymes of cholinergic (acetylcholinesterase) and purinergic (nucleoside triphosphate diphosphohydrolase; NTPDase, 5' nucleotidase and adenosine deaminase; ADA) systems in BV-2 microglial cells were determined. Incubation of BV-2 microglia cell with M. oleifera extract maintained cell viability, modulated cholinergic and purinergic enzymes activity. The phenolic compounds found in M. oleifera extracts, include chlorogenic acid, rutin; quercetin pentoside, kaempferol derivative and quercetin derivative. Thus, this study suggest that the potential therapeutic effect of the phenolic compounds found in M. oleifera may have been responsible for the maintenance of cell viability in BV-2 microglia cells and modulation of cholinergic as well as purinergic enzymes activity.

Toona sinensis modulates autophagy and cytokines in lipopolysaccharide-induced RAW 264.7 macrophages

Toona sinensis (TS) is a medicinal herb possessing anti-apoptotic, anti-oxidant, and anti-inflammatory properties and is used to treat diabetes, cancer, and inflammatory diseases. In traditional Chinese medicine theory, TS clears dampness and heat, strengthens the stomach function, and regulates vital energy flow. TS is also used as an astringent and a pesticide. In this study, we aimed to evaluate how TS influences autophagy and cytokines during the inflammatory process in RAW 264.7 macrophages. The treatment groups were pre-supplemented with TS leaf extract; rapamycin was used to enhance autophagy and lipopolysaccharide (LPS) was used to induce inflammation. The expression of autophagy-related proteins was analyzed by western blotting. The survival rate of, and chemokine expression and oxidative stress in the cells were also assessed. TS leaf extract inhibited mammalian target of rapamycin (mTOR) phosphorylation at site S2448 in the macrophages. At relatively higher concentrations (50 and 75 μg/mL), TS elevated the expression of light chain 3 II (LC3-II), which further modulated autophagy. Pre-supplementation with TS leaf extract elevated the total glutathione (GSH) level and GSH/oxidized GSH (GSSG) ratio, but it decreased the GSSG, total nitric oxide, nitrate, nitrite, malondialdehyde, and superoxide anion levels. TS reversed the effects of LPS-induced cytokines, including interleukin (IL)-6 and IL-10. TS did not induce significant toxicity at the studied concentrations. In conclusion, TS leaf extract may modulate autophagy during inflammation. Furthermore, it may prevent cell damage via anti-inflammation and anti-oxidation. Thus, this study supports the ethnomedical use of TS in the prevention of inflammation-related diseases.

Polyphenols from Toona sinensiss Seeds Alleviate Neuroinflammation Induced by 6-Hydroxydopamine Through Suppressing p38 MAPK Signaling Pathway in a Rat Model of Parkinson's Disease

Polyphenols from Toona sinensis seeds (PTSS) have demonstrated anti-inflammatory effects in various diseases, while the anti-neuroinflammatory effects still remain to be investigated. We aimed to investigate the effects of PTSS on Parkinson's disease and underlying mechanisms using a rat model. We employed 6-hydroxydopamine (6-OHDA) to male Sprague Dawley (SD) rats and PC12 cells to construct the in vivo and vitro models of PD and dopaminergic (DA) neuron injury, respectively. Cell viability was detected by cell counting kit-8 (CCK-8) assay and protein levels of inflammatory mediators and some p38 MAPK pathway molecules were investigated by immunohistochemistry and Western blot analyses. The results showed that 6-OHDA significantly increased protein levels of inflammatory mediators, such as cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and tumor necrosis factor α (TNF-α), which could be reversed by PTSS through suppressing the p38 MAPK pathway. The anti-inflammatory effects of PTSS were significantly enhanced by the specific p38 inhibitor of SB203580 in vitro. The present work suggests that PTSS can exert anti-inflammatory effects on PD models, which may be attributed to the suppression of p38 MAPK signaling pathway.

Anti-neuroinflammatory potential of Tylophora indica (Burm. f) Merrill and development of an efficient in vitro propagation system for its clinical use

Neuroinflammation is a major risk factor associated with the pathogenesis of neurodegenerative diseases. Conventional non-steroidal anti-inflammatory drugs are prescribed but their long term use is associated with adverse effects. Thus, herbal based medicines are attracting major attraction worldwide as potential therapeutic candidates. Tylophora indica (Burm. f) Merrill is a valuable medicinal plant well known in Ayurvedic practices for its immunomodulatory, anti-oxidant, anti-asthmatic and antirheumatic activities. The present study aimed to elucidate the anti-neuroinflammatory potential of water and hydroalcoholic leaf extracts of micropropagated plants of T. indica using BV-2 microglia activated with lipopolysaccharide as an in vitro model system and development of an efficient reproducible protocol for its in vitro cloning. Non cytotoxic doses of the water and hydroalcoholic extracts (0.2μg/ml and 20μg/ml, respectively) were selected using MTT assay. α-Tubulin, Iba-1 and inflammatory cascade proteins like NFκB, AP1 expression was studied using immunostaining to ascertain the anti-neuroinflammatory potential of these extracts. Further, anti-migratory activity was also analyzed by Wound Scratch Assay. Both extracts effectively attenuated lipopolysaccharide induced microglial activation, migration and the production of nitrite via regulation of the expression of NFκB and AP1 as the possible underlying target molecules. An efficient and reproducible protocol for in vitro cloning of T. indica through multiple shoot proliferation from nodal segments was established on both solid and liquid Murashige and Skoog’s (MS) media supplemented with 15μM and 10μM of Benzyl Amino Purine respectively. Regenerated shoots were rooted on both solid and liquid MS media supplemented with Indole-3-butyric acid (5–15μM) and the rooted plantlets were successfully acclimatized and transferred to open field conditions showing 90% survivability. The present study suggests that T. indica may prove to be a potential anti-neuroinflammatory agent and may be further explored as a potential therapeutic candidate for the management of neurodegenerative diseases. Further, the current study will expedite the conservation of T. indica ensuring ample supply of this threatened medicinal plant to fulfill its increasing demand in herbal industry.

Toona sinensis: a comprehensive review on its traditional usages, phytochemisty, pharmacology and toxicology

Toona sinensis (Juss.) M.Roem, Meliaceae, a deciduous plant native to eastern and southeastern Asia, is widely used in Traditional Chinese Medicine. This paper was aimed to summarize the current advances in traditional usage, phytochemistry, pharmacology and toxicology of T. sinensis. In this review, various types of data of T. sinensis are discussed in the corresponding parts of this paper, and perspectives for possible future studies of this plant are discussed. The main constituents of T. sinensis are terpenoids, phenylpropanoids and flavonoids, etc., and its pharmacological activities include anti-tumor effects, antioxidant activities, anti-diabetic effects and anti-inflammatory effects. Although a series of phytochemical and pharmacological researches of this plant have been conducted, the active constituents and action mechanism of these activities should be also further explored. Furthermore, the present review also indicates that T. sinensis has potentials to develop into drugs for treating various diseases with high efficacy and low toxicity, particularly in cancer, diabetes and inflammatory disorders. In conclusion, the paper provides a full-scale profile of the traditional usage, phytochemistry, pharmacology and toxicology of T. sinensis, and also provides potential therapeutic uses and drug development prospects of this plant.

Quantitative Analysis and Comparison of Four Major Flavonol Glycosides in the Leaves of Toona sinensis (A. Juss.) Roemer (Chinese Toon) from Various Origins by High-Performance Liquid Chromatography-Diode Array Detector and Hierarchical Clustering Analysis

Background:

Toona sinensis (A. Juss.) Roemer is an endemic species of Toona genus native to Asian area. Its dried leaves are applied in the treatment of many diseases; however, few investigations have been reported for the quantitative analysis and comparison of major bioactive flavonol glycosides in the leaves harvested from various origins.

Objective:

To quantitatively analyze four major flavonol glycosides including rutinoside, quercetin-3-O-β-D-glucoside, quercetin-3-O-α-L-rhamnoside, and kaempferol-3-O-α-L-rhamnoside in the leaves from different production sites and classify them according to the content of these glycosides.

Materials and Methods:

A high-performance liquid chromatography-diode array detector (HPLC-DAD) method for their simultaneous determination was developed and validated for linearity, precision, accuracy, stability, and repeatability. Moreover, the method established was then employed to explore the difference in the content of these four glycosides in raw materials. Finally, a hierarchical clustering analysis was performed to classify 11 voucher specimens.

Results:

The separation was performed on a Waters XBridge Shield RP18 column (150 mm × 4.6 mm, 3.5 μm) kept at 35°C, and acetonitrile and H₂O containing 0.30% trifluoroacetic acid as mobile phase was driven at 1.0 mL/min during the analysis. Ten microliters of solution were injected and 254 nm was selected to monitor the separation. A strong linear relationship between the peak area and concentration of four analytes was observed. And, the method was also validated to be repeatable, stable, precise, and accurate.

Conclusion:

An efficient and reliable HPLC-DAD method was established and applied in the assays for the samples from 11 origins successfully. Moreover, the content of those flavonol glycosides varied much among different batches, and the flavonoids could be considered as biomarkers to control the quality of Chinese Toon.

SUMMARY

Four major flavonol glycosides in the leaves of Toona sinensis were determined by HPLC-DAD and their contents were compared among various origins by HCA.

Abbreviations used: HPLC-DAD: High-performance liquid chromatography-diode array detector, HCA: Hierarchical clustering analysis, MS: Mass spectrometry, RSD: Relative standard deviation.

Limonoids isolated from Toona sinensis and their radical scavenging, anti-inflammatory and cytotoxic activities

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Ten new limonoids were obtained from Toona sinensis (A. Juss.) Roem.

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Limonoid 4 display potent ABTS^⋅+ scavenging activity.

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Limonoids 5 and 7–10 possessed the high ABTS^⋅+ and DPPH scavenging activities.

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Limonoids 1–4 and 11 showed the elective inhibition of Cox-1.

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Limonoids 1–4 and 11 exhibited the significant cytotoxicities.

A phytochemical investigation of the ethanol extract of Toona sinensis (A. Juss.) Roem resulted in the isolation of ten new limonoids, toonasinenines A–J (1–10), together with two known compounds, toonafolin (11) and toonacilianin D (12). Their structures were determined by spectroscopic analyses. The isolated components were evaluated in vitro for radical scavenging potential using ABTS^⋅+ and DPPH test, anti-inflammatory activities for Cox-1 and Cox-2, and cytotoxicies against nine tumour cell lines (A549, BGC-823, CHG-5, HCT15, HeLa, HepG2, MDA-MB-231, SHG-44 and SGC-7901 cells). As a result, 4, 5 and 7–10 showed potent radical scavenging activities, while limonoids 1–4 and 11 exhibited significant anti-inflammatory and cytotoxic potential.