Beneficial effect of Toona sinensis Roemor on improving cognitive performance and brain degeneration in senescence-accelerated mice

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.

Anti-Septic Potential of 7-α-Obacunyl Acetate Isolated from the Toona sinensis on Cecal Ligation/Puncture Mice via Suppression of JAK-STAT/NF-κB Signal Pathway

Purpose

Sepsis is a life-threatening clinical syndrome and characterized by an inflammatory and innate immune response to infections. The current study was aimed to evaluate the anti-sepsis effect of 7-α-Obacunyl acetate (7-OBA), the abundant constituent isolated from Toona sinensis (Meliaceae), in cecal ligation and puncture (CLP)-induced mice and to investigate the related molecular mechanisms.

Methods

The CLP operation was performed to establish the sepsis mice model, and the survival rate and temperature were measured after 7-OBA treatment (7.5, 15, and 30 mg/kg; i.p.). Inflammatory cytokines levels of TNF-α, IL-1β, IL-6, and IL-10 were detected by ELISA kits, and the kidney, liver, and heart function were measured using an automatic biochemistry analyzer. Effects of 7-OBA on NF-κB and JAK2-STAT3 signaling pathways were determined by Western blot analysis in a lipopolysaccharide (LPS) stimulated RAW264.7 cells model.

Results

7-OBA treatment significantly increased the survival rate (p<0.05 and p<0.01) and normalized temperature (p<0.05 and p<0.01) of sepsis mice. The levels of pro-inflammatory cytokines like TNF-α, IL-1β, and IL-6 in serum were obviously decreased, whereas the anti-inflammatory cytokines of IL-10 were increased. CLP-induced increases of the main markers of kidney, liver, and heart function in mice (p<0.01) were also obviously reversed by 7-OBA. The anti-sepsis effect of 7-OBA might be associated with regulation of nuclear factor kappa-B (NF-κB) and Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signal pathways.

Conclusion

Our investigation indicated that 7-OBA can be developed as an effective agent for treating/curing sepsis in the future.

Toona sinensis Inhibits Murine Leukemia WEHI-3 Cells and Promotes Immune Response In Vivo

Toona sinensis (TS) is one of the most popular vegetarian dishes in Taiwan. It has been shown to exhibit antioxidant, antiangiogenic, antiatherosclerotic, and anticancer properties. In this study, we demonstrated the ability of aqueous leaf extracts from TS to promote immune responses in BALB/c mice and to exhibit anti-leukemia activity in murine WEHI-3 cells. BALB/c mice were injected intravenously with WEHI-3 cells and then treated orally with TS (50 mg/kg). In vivo study showed that TS treatment reduced liver and spleen enlargement in WEHI-3 bearing mice compared with the untreated group. Furthermore, TS also decreased white blood cells (WBC), indicating inhibition of differentiation of the precursor of macrophages in WEHI-3 bearing mice. Treatment of WEHI-3 cells with TS (0-75 μg/mL for 24 hours) significantly reduced cell viability. Furthermore, TS treatment-induced late apoptosis was confirmed by Annexin-V/PI staining. Western blot analyses revealed that treatment of WEHI-3 cells with TS statistically increased the protein expression level of cytochrome c in the cytoplasm and activates caspase-3. Notably, TS treatment caused a dramatic reduction in Bcl-2 and increase in Bax protein levels. TS may disturb the Bcl-2 and Bax protein ratio and induce apoptosis. This reports confirms the antitumor activity of this nutritious vegetable potentially against leukemia.

Toona sinensis leaf extract inhibits lipid accumulation through up-regulation of genes involved in lipolysis and fatty acid oxidation in adipocytes

Toona sinensis leaf (TSL) has been shown to lower plasma triacylglycerol levels and diminish the size of visceral fat cells in vivo. The molecular mechanism of TSL ethanol extract (TSL-E) on lipid metabolism in 3T3-L1 adipocytes was investigated in this study. Oil Red O staining as well as immunoblotting, real-time PCR, and dual-Luciferase reporter system were performed to investigate the effect of TSL-E on lipid accumulation and the regulation of lipid metabolism, respectively. In addition, active compounds in the TSL-E were analyzed by HPLC. TSL-E significantly decreased lipid accumulation, stimulated free fatty acid (FFA) release, and up-regulated peroxisome proliferator-activated receptor-α (PPARα) and genes involved in peroxisomal (acyl-CoA oxidase) and mitochondrial (uncouple protein 3) fatty acid oxidation. TSL-E also up-regulated cytoplasmic triacylglycerol hydrolysis gene (adipose triglyceride lipase) and genes related to fatty acid oxidation (AMP-activated protein kinase, acetyl-CoA carboxylase, carnitine palmitoyltransferase I, PPARγ, and adiponectin). The major constituents directly inducing PPARα transactivity in TSL-E are gallic acid, rutin, palmitic acid, linoleic acid, and α-linolenic acid. These results indicate that the inhibitory effect of TSL-E on lipid accumulation was through PPARα activation and further up-regulation of PPARα-mediated genes plus up-regulation of cytoplasmic genes involved in lipid catabolism.

Toona sinensis leaf aqueous extract displays activity against sepsis in both in vitro and in vivo models

Toona sinensis (TS) leaves are used as a vegetable and in traditional Chinese medicine. However, in vivo experiments regarding the anti-inflammatory function of TS leaves have not previously been conducted. The aim of this study was to investigate the potential role of TS leaf extract (TSL) in the prevention of sepsis-induced lung injury in vivo and on macrophage activation in vitro. The results showed that oral gavage pretreatment with TSL in rats for 30 days improved the survival of cecal ligation and puncture-induced sepsis, potentially by attenuating sepsis-induced histological lung damage rather than inflammatory cell infiltration. Furthermore, we demonstrated that pretreatment with TSL attenuated the lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase, thereby inhibiting nitric oxide production and release in murine macrophage-like RAW 264.7 cells. Interestingly, TSL did not affect the LPS-induced release of other cytokines (e.g., tumor necrosis factor α and interleukin 1β) but increased LPS-induced heme-oxygenase-1 expression. In conclusion, the study provides preliminary data for TSL on cecal ligation and puncture-induced sepsis. The beneficial impact of TSL needs extensive study to get solid evidence.

Toona sinensis inhibits LPS-induced inflammation and migration in vascular smooth muscle cells via suppression of reactive oxygen species and NF-κB signaling pathway

Toona sinensis is one of the most popular vegetarian cuisines in Taiwan and it has been shown to possess antioxidant, antiangiogenic, and anticancer properties. In this study, we investigated the antiatherosclerotic potential of aqueous leaf extracts from Toona sinensis (TS; 25–100 μg/mL) and its major bioactive compound, gallic acid (GA; 5 μg/mL), in LPS-treated rat aortic smooth muscle (A7r5) cells. We found that pretreatment with noncytotoxic concentrations of TS and GA significantly inhibited inflammatory NO and PGE₂ production by downregulating their precursors, iNOS and COX-2, respectively, in LPS-treated A7r5 cells. Furthermore, TS and GA inhibited LPS-induced intracellular ROS and their corresponding mediator, p47^phox. Notably, TS and GA pretreatment significantly inhibited LPS-induced migration in transwell assays. Gelatin zymography and western blotting demonstrated that treatment with TS and GA suppressed the activity or expression of MMP-9, MMP-2, and t-PA. Additionally, TS and GA significantly inhibited LPS-induced VEGF, PDGF, and VCAM-1 expression. Further investigation revealed that the inhibition of iNOS/COX-2, MMPs, growth factors, and adhesion molecules was associated with the suppression of NF-κB activation and MAPK (ERK1/2, JNK1/2, and p38) phosphorylation. Thus, Toona sinensis may be useful for the prevention of atherosclerosis.

Toona Sinensis and Moschus Decoction Induced Cell Cycle Arrest in Human Cervical Carcinoma HeLa Cells

Toona sinensis and Moschus are two herb materials used in traditional Chinese medicine, most commonly for their various biological activities. In this study, we investigated the inhibitory effect of three decoctions from Toona sinensis, Moschus, and Toona sinensis and Moschus in combination on cell growth in several normal and cancer cell lines by cell viability assay. The results showed that the combined decoction exhibited the strongest anticancer effects, compared to two single decoctions. The observations indicated that the combined decoction did not induce cell apoptosis and autophagy in HeLa cells by fluorescence microscopy. Flow cytometry analysis revealed that the combined decoction arrested HeLa cell cycle progression in S-phase. After the decoction incubation, among 41 cell cycle related genes, eight were reduced, while five were increased in mRNA levels by real-time PCR assay. Western blotting showed that there were no apparent changes of protein levels of Cyclin E1, while P27 expression significantly declined and the levels of CDC7 and CDK7 obviously increased. The data suggest that the RB pathway is partially responsible for the decoction-induced S-phase cell cycle arrest in HeLa cells. Therefore, the combined decoction may have therapeutic potential as an anticancer formula for certain cancers.

n-Butanol soluble fraction of the water extract of Chinese toon fruit ameliorated focal brain ischemic insult in rats via inhibition of oxidative stress and inflammation

AIM OF THE STUDY

Toona sinensis Roem. (Meliaceae; Toona sinensis; Chinese toon) is a type of arbor that is widely distributed in Asia. The fruits of Toona sinensis Roem has been traditionally recognized for treatment of cerebrovascular diseases. To evaluate the potential clinical use of the fruits of Toona sinensis Roem, we determined the dose dependence of the neuroprotective efficacy in a focal cerebral ischemic reperfusion model of rats and explored the underlying mechanisms.

MATERIALS AND METHODS

Rats were subjected to occlusion of the middle cerebral artery (MCAO) by a nylon filament and treated with different doses (20mg/kg and 30 mg/kg) of n-butanol soluble fraction of the water extract of Chinese toon fruit or the vehicle for 1 week before induction of ischemia, s.i.d..

RESULTS

n-Butanol soluble fraction of the water extract of Chinese toon fruit reduced in a dose-dependent manner the ischemia-induced cerebral infarct and edema volume and attenuated neurological deficits observed at 6h point after ischemia. n-Butanol soluble fraction of the water extract of Chinese toon fruit reduced the levels of nitrate, nitrite, lipid peroxidation, cyclooxygenase-1, thromboxane in post-ischemic brain. n-Butanol soluble fraction of the water extract of Chinese toon fruit adjusted the elevation of the activity of glutathione peroxidase and superoxide dismutase in ischemic brain.

CONCLUSIONS

The present study was the first evidence of effectiveness of n-butanol soluble fraction of the water extract of Chinese toon fruit in the rat stroke models, as it reduced infarct volume, inhibited the oxidative stress and inflammation.

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

The leaves of Toona sinensis, a well‐known traditional oriental medicine, have been prescribed for the treatment of enteritis and infection. Recently, aqueous extracts of Toona sinensis leaves (TSL‐1) have demonstrated many biological effects both in vitro and in vivo. In the central nervous system, microglial activation and their proinflammatory responses are considered an important therapeutic strategy for neuroinflammatory disorders such as cerebral ischemia, Alzheimer's disease, and Parkinson's disease. The present study attempted to validate the effect of TSL‐1 on microglia‐mediated neuroinflammation stimulated by lipopolysaccharide (LPS). As inflammatory parameters, the production of nitric oxide (NO), inducible NO synthase, and tumor necrosis factor‐α were evaluated. Our results demonstrate that TSL‐1 suppresses LPS‐induced NO production, tumor necrosis factor‐α secretion, and inducible NO synthase protein expression in a concentration‐dependent manner, without causing cytotoxicity. In addition, the inhibitory effects of TSL‐1 in LPS‐stimulated BV‐2 microglia were extended to post‐treatment suggesting the therapeutic potential of TSL‐1. Therefore, this work provides the future evaluation of the role of TSL‐1 in the treatment of neurodegenerative diseases by inhibition of inflammatory mediator production in activated microglia.

The Effectiveness and Mechanism of Toona sinensis Extract Inhibit Attachment of Pandemic Influenza A (H1N1) Virus

TSL-1 is a fraction of the aqueous extract from the tender leaf of Toona sinensis Roem, a nutritious vegetable. The pandemic influenza A (H1N1) virus is a recently described, rapidly contagious respiratory pathogen which can cause acute respiratory distress syndrome (ARDS) and poses a major public health threat. In this study, we found that TSL-1 inhibited viral yields on MDCK plaque formation by pandemic influenza A (H1N1) virus on infected A549 cells with high selectivity index. Meanwhile, TSL-1 also suppressed viral genome loads in infected A549 cells, quantified by qRT-PCR. This study further demonstrated that TSL-1 inhibited pandemic influenza A (H1N1) virus activity through preventing attachment of A549 cells but not penetration. TSL-1 inhibited viral attachment through significant downregulation of adhesion molecules and chemokines (VCAM-1, ICAM-1, E-selectin, IL-8, and fractalkine) compared to Amantadine. Our results suggest that TSL-1 may be used as an alternative treatment and prophylaxis against pandemic influenza A (H1N1) virus.

Therapeutic Effect of Yi-Chi-Tsung-Ming-Tang on Amyloid β-Induced Alzheimer's Disease-Like Phenotype via an Increase of Acetylcholine and Decrease of Amyloid β

Alzheimer's disease (AD) is an irreversible neurodegenerative disorder characterized by amyloid accumulation, neuronal death, and cognitive impairments. Yi-Chi-Tsung-Ming-Tang (YCTMT) is a traditional Chinese medicine and has never been used to enhance cognitive function and treat neurodegenerative disorders such as senile dementia. Whether YCTMT has a beneficial role in improving learning and memory in AD patients remains unclear. The present study showed that oral administration of YCTMT ameliorated amyloid-β- (Aβ₁₋₄₀) injection-induced learning and memory impairments in rats, examined using passive avoidance and Morris water-maze tests. Immunostaining and Western Blot results showed that continuous Aβ₁₋₄₀ infusion caused amyloid accumulation and decreased acetylcholine level in hippocampus. Oral administration of medium and high dose of YCTMT 7 days after the Aβ₁₋₄₀ infusion decreased amyloid accumulation area and reversed acetylcholine decline in the Aβ₁₋₄₀-injected hippocampus, suggesting that YCTMT might inhibit Aβ plague accumulation and rescue reduced acetylcholine expression. This study has provided evidence on the beneficial role of YCTMT in ameliorating amyloid-induced AD-like symptom, indicating that YCTMT may offer an alternative strategy for treating AD.

Toona sinensis Roem leaf extracts improve antioxidant activity in the liver of rats under oxidative stress

Toona sinensis Roem (TS) is an herbal plant widely cultivated in Asia. Recently, several antioxidant compounds in TS leaf (TSL) extracts were chemically identified including quercetin, gallic acid, and others. However, in vivo experiments regarding the antioxidative function of TSL are limited. In this study, Sprague Dawley (SD) rats with oxidative stress were successfully established by intraperitoneal injection of hydrogen peroxide (H(2)O(2)) (1mmol/kg BW) and fed with different TSL extracts for in vivo antioxidation evaluation. Among the TSLs tested in this study, TSL6 exhibited the best antioxidative effects which increased the enzyme activities of catalase, cupper/zinc superoxide dismutase (Cu/Zn SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and Glutathione S transferase (GST) activities in liver compared to those in TSL-2 and TSL-2P groups. In conclusion, we provide the strong in vivo evidences for the first time that TSL extracts ameliorate the antioxidant enzymes (AOEs) activity in liver and is beneficial for the hepatic detoxification.

Antioxidant activities of aqueous leaf extracts of Toona sinensis on free radical-induced endothelial cell damage

ETHNOPHARMACOLOGICAL RELEVANCE

In Taiwan, Toona sinensis (Toona sinensis) is well known as a traditional Chinese medicine, while the underlying pharmacological mechanisms of this drug are still a matter of debate.

MATERIALS AND METHODS

The purpose of this study was to evaluate the protective effects of non-cytotoxic concentrations of aqueous leaf extracts of Toona sinensis (TS extracts; 50-100 μg/mL) and gallic acid (5 μg/mL), a major component of these extracts, against AAPH-induced oxidative cell damage in human umbilical vein endothelial cells (ECs).

RESULTS

Exposure of ECs to AAPH (15 mM) decreased cell viability from 100% to 43%. However, ECs were pre-incubated with TS extracts prior to AAPH induction resulted in increased resistance to oxidative stress and cell viability in a dose-dependent manner. An increase in ECs-derived PGI(2) and IL-1 β in response to AAPH exposure was positively correlated with cytotoxicity and negatively with TS extracts concentrations. In addition, gallic acid also suppressed PGI(2) and IL-1 β production in AAPH-induced ECs. Notably, TS extracts/gallic acid treatment significantly inhibited ROS generation, MDA formation, SOD/catalase activity, and Bax/Bcl-2 dysregulation in AAPH-stimulated ECs. Pretreatment of ECs with TS extracts/gallic acid also suppressed AAPH-induced cell surface expression and secretion of VCAM-1, ICAM-1 and E-selectin, which was associated with abridged adhesion of U937 leukocytes to ECs. Moreover, TS extracts/gallic acid treatment significantly inhibited the AAPH-mediated up regulation of PAI-1 and down regulation of t-PA in ECs, which may decrease fibrinolytic activity.

CONCLUSIONS

Therefore, Toona sinensis may possess antioxidant properties that protect endothelial cells from oxidative stress. Our results also support the traditional use of Toona sinensis in the treatment of free radical-related diseases and atherosclerosis.

Toona sinensis (leaf extracts) inhibit vascular endothelial growth factor (VEGF)-induced angiogenesis in vascular endothelial cells

AIM OF THE STUDY

Toona sinensis is well known as a traditional Chinese medicine; also, it has been shown to exhibit anticancer and anti-inflammatory effects. This study was aimed at evaluating the anti-angiogenesis effect of the aqueous extracts of Toona sinensis (TS extracts) or gallic acid, a major component of TS extracts, against both VEGF-induced EA.hy 926 and human umbilical vein endothelial cells (HUVECs).

MATERIALS AND METHODS

Anti-proliferative activity of TS extracts or gallic acid, was determined against EA.hy 926 and HUVECs by trypan blue exclusion method. Invasion, tube formation and chick chorioallantoic membrane assay were carried out to determine the in vitro and in vivo anti-angiogenic effects.

RESULTS

Non-cytotoxic concentration of TS extracts (50-100μg/mL) and gallic acid (5μg/mL) inhibited the proliferation of VEGF-stimulated EA.hy 926 and HUVECs. Inhibitory effects of TS extracts and gallic acid on angiogenesis were assessed by VEGF-induced migration/invasion and capillary-like tube formation by EA.hy 926 and HUVECs. Additionally, gelatin zymography assays showed that TS extracts and gallic acid suppressed the activity of metalloproteinase (MMP)-9 and MMP-2 activated by VEGF. In vivo, TS extracts and gallic acid strongly suppressed neovessel formation in the chorioallantoic membrane of chick embryos. Flow cytometry analyses and Western blot demonstrated that treatment with TS extracts and gallic acid induced G(0)/G(1) arrest in VEGF-stimulated EA.hy 926 cells via a reduction in the amounts of cyclin D1, cyclin E, CDK4, hyperphosphorylated retinoblastoma protein (pRb), VEGFR-2, and eNOS.

CONCLUSIONS

These results support an anti-angiogenic activity of Toona sinensis that may contribute critically to its cancer and inflammation chemopreventive potentials.

Antiproliferative and antitumorigenic activity of Toona sinensis leaf extracts in lung adenocarcinoma

Toona sinensis is a traditional Chinese herb, and the extracts of T. sinensis leaf possess a variety of biological functions. This study attempted to test the antiproliferative effect of TSL-1 (a bioactive fraction of T. sinensis) in H441 cells (lung adenocarcinoma). The data showed that the antiproliferative effect of TSL-1 on H441 cells is prominent using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. TSL-1-induced apoptosis was confirmed by cell morphology, sub-G(1) peak accumulation, cleavage of poly(ADP)-ribose polymerase, and propidium iodide-annexin V double staining. Furthermore, decreased Bcl-2 accompanied by increased Bax (in western blotting) was found with TSL-1 treatment of H441 cells. TSL-1 treatment-induced G(1) arrest was concurrent with the down-regulation of protein levels of cyclin D1 and cyclin-dependent kinase 4 in H441 cells. Peroral and intraperitoneal administrations of TSL-1 were performed to evaluate the therapeutic efficacy, and peroral administration of TSL-1 was also used to elucidate the therapeutic efficacy in the H441 cell xenograft model in vivo. The data revealed that TSL-1 treatment inhibited H441 tumor growth in both therapeutic and preventive experiments. Taken together, these results demonstrate that TSL-1 possesses the capability of preventing and alleviating lung cancer proliferation in vitro and in vivo with proven nephrological and hepatic safety and has the potential to be developed as an anti-lung cancer drug.

The senescence-accelerated mouse (SAM): a higher oxidative stress and age-dependent degenerative diseases model

The SAM strain of mice is actually a group of related inbred strains consisting of a series of SAMP (accelerated senescence-prone) and SAMR (accelerated senescence-resistant) strains. Compared with the SAMR strains, the SAMP strains show a more accelerated senescence process, a shorter lifespan, and an earlier onset and more rapid progress of age-associated pathological phenotypes similar to human geriatric disorders. The higher oxidative stress status observed in SAMP mice is partly caused by mitochondrial dysfunction, and may be a cause of this senescence acceleration and age-dependent alterations in cell structure and function. Based on our recent observations, we discuss a possible mechanism for mitochondrial dysfunction resulting in the excessive production of reactive oxygen species, and a role for the hyperoxidative stress status in neurodegeneration in SAMP mice. These SAM strains can serve as a useful tool to understand the cellular mechanisms of age-dependent degeneration, and to develop clinical interventions.

Safety evaluation of water extracts of Toona sinensis Roemor leaf

The purposes of this study were to evaluate the safety of water extracts of Toona sinensis Roemor leaf (TSL-1). The mutagenic properties of TSL-1 was investigated using the Ames test, and no mutagenicity was found toward all tester strains (Salmonella typhimurium TA98, TA100, TA102 and TA1535). In the acute oral toxicity study, a single limit dose of 5000 mgTSL-1/kg bw was given to male and female ICR mice, then observed for a 14-day period. In the subacute study, TSL-1 was administered as oral daily dose of 1000 mg/kg bw/day for 28 days. The results showed no acute lethal effect at a maximal tested dose of 5000 mg/kg bw TSL-1 in male and female mice. The subacute toxicity showed the oral administration of 1000 mg/kg bw for consecutive 28 days was safe in male mice. TSL-1 treated female mice showed decreases of food intake and kidney relative weight in acute oral toxicity test, and decreases of body weight gain, food intake and lung relative weight in subacute toxicity trial. However, no remarked toxic effects were found in the biochemical and histopathological parameters of TSL-1 treated female mice. These effects whether related to the major components or other ingredients in TSL-1 need to elucidate in the further studies.