Essential oil of Curcuma wenyujin induces apoptosis in human hepatoma cells

AIM: To investigate the effects of the essential oil of Curcuma wenyujin (CWO) on growth inhibition and on the induction of apoptosis in human HepG2 cancer cells. METHODS: The cytotoxic effect of drugs on HepG2 cells was measured by 3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetra-zolium bromide (MTT) assay. DNA fragmentation was visualized by agarose gel electrophoresis. Cell cycle and mitochondrial transmembrane potential (△Ψm) were determined by flow cytometry (FCM). Cytochrome C immunostaining was evaluated by fluorescence microscopy. Caspase-3 enzymatic activity was assayed by the cleavage of Ac-DEVD-R110. Cleaved PARP and active caspase-3 protein levels were measured by FCM using BD? CBA Human Apoptosis Kit. RESULTS: Treatment with CWO inhibited the growth of HepG2 cells in a dose-dependent manner, and the IC50 of CWO was approximately 70 μg/mL. CWO was found to inhibit the growth of HepG2 cells by inducing a cell cycle arrest at S/G2. DNA fragmentation was evidentlyobserved at 70 μg/mL after 72 h of treatment. During the process, cytosolic HepG2 cytochrome C staining showed a markedly stronger green fluorescence than in control cells in a dose-dependent fashion, and CWO also caused mitochondrial transmembrane depolarization. Furthermore, the results clearly demonstrated that both, activity of caspase-3 enzyme and protein levels of cleaved PARP, significantly increased in a dose- dependent manner after treatment with CWO. CONCLUSION: CWO exhibits an antiproliferative effect in HepG2 cells by inducing apoptosis. This growth inhibition is associated with cell cycle arrest, cytochrome C translocation, caspase 3 activation, Poly- ADP-ribose polymerase (PARP) degradation, and loss of mitochondrial membrane potential. This process involves a mitochondria-caspase dependent apoptosis pathway. As apoptosis is an important anti-cancer therapeutic target, these results suggest a potential of CWO as a chemotherapeutic agent.

白藜芦醇及其衍生物在TNF-α诱导的人脐静脉内皮细胞中的抗炎作用

二苯乙烯类化合物，自1940年首次从毛藜芦根中分离出白藜芦醇以来就对此进行了广泛研究。这类化合物存在于许多植物中并具有广泛的生理活性，主要有抗氧化、抗肿瘤、抗淤血综合征（如脑炎、动脉粥样硬化、慢性炎症）等。白藜芦醇（trans-3，5，4’-trihydroxystiibene），是从中药虎杖中提取出来的一种二苯乙烯类化合物，同时也是一种非常重要的植物内毒素，在近年来的实验研究中已充分证明其具有很多有益的药理作用，如抗癌、心血管保护、神经保护、抗衰老和抗炎等等。大量研究证实其在抗动脉粥样硬化中起着非常重要的作用。近年来随着白藜芦醇的类似物的不断出现，研究者们发现其中一些二苯乙烯类化合物同样具有许多与白藜芦醇相似的药理活性且某些化合物的活性、选择性及稳定性均要强于白藜芦醇，故成为目前研究的热点。为了探讨白藜芦醇类似物中甲基化白藜芦醇和自藜芦醇苷的抗炎效应并阐明其作用机制，同时与白藜芦醇进行比较，我们首先用细胞黏附实验测定其是否具有抗细胞黏附的能力，然后对其相关的黏附分子的表达及NF—κB进行考察。

No synergism between bis(propyl)-cognitin and rasagiline on protecting dopaminergic neurons in Parkinson's disease mice

Rasagiline,a monoamine oxidase-B inhibitor,and bis（propyl）-cognitin（B3C）,a novel dimer are reported to be neuroprotective.Herein,the synergistical neuroprotection produced by rasagiline and B3 C was investigated in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（MPTP）-induced mice of Parkinsonism.By using neurobehavioural tests,high-performance liquid chromatography and western blot assay,we showed that B3 C at 0.3 mg/kg,rasagiline at 0.02 mg/kg,as well as co-treatment with B3 C and rasagiline prevented MPTP-induced behavioural abnormities,increased the concentrations of dopamine and its metabolites in the striatum,and up-regulated the expression of tyrosine hydroxylase in the substantia nigra.However,the neuroprotective effects of co-treatment were not significantly improved when compared with those of B3 C or rasagiline alone.Collectively,we have demonstrated that B3 C at 0.3 mg/kg and rasagline at 0.02 mg/kg could not produce synergistic neuroprotective effects.

Novel Kunitz-like peptides discovered in zoanthid Palythoa caribaeorum through transcriptome sequencing

OBJECTIVE Palythoa caribaeorum(class Anthozoa) is a zoanthid that together jellyfishes,hydra,and sea anemones,which are venomous and predatory,belongs to the Phyllum Cnidaria.The distinguished feature in these marine animals is the cnidocytes in the body tissues,responsible for toxin production and injection that are used majorly for prey capture and defense.With exception for other anthozoans,the toxin cocktails of zoanthids have been scarcely studied and are poorly known.METHODS Based on the analysis of P.caribaeorum transcriptome,numerous predicted venom-featured polypeptides were identified,including allergens,neuro-toxins,membrane-active and Kunitz-like peptides(PcKuz).The three predicted PcKuz isotoxins(1 to 3) were selected for functional studies.Through computational processing comprising structural phylogenetic analysis,molecular docking,and dynamics simulation,PcKuz3 was shown to be a potential voltage gated potassium-channel inhibitor.RESULTS PcKuz3 fitted well as new functional Kunitz-type toxins with strong anti-locomotor activity as in vivo assessed in zebrafish larvae,with weak inhibitory effect toward proteases,as evaluated in vitro.Notably,PcKuz3 can suppress,at low concentration,the 6-OHDA-induced neurotoxicity on the locomotive behavior of zebrafish,which indicated PcKuz3 may have a neuroprotective effect.CONCLUSION Taken together,PcK uz3 figures as a novel neurotoxin structure which differs from known homologous peptides expressed in sea anemone.Moreover,the novel PcKuz3 provides an insightful hint for bio-drug development for prospective neurodegenerative disease treatment.

Structural and functional characterization of a novel ShK peptide and its analogue from zoanthids (corals)

OBJECTIVE To identify and characterize a novel neuroprotective ShK peptide and its analogue originated from coral P.caribaeoru.METHODS P.caribaeoru was collected and subjected to transcriptome sequencing at which further bioinformatics analysis had identified a unigene encoding a putative ShK protein candidate,named as PcShK1.PcShK1 and its rhodamine derivative(PcShK1-RhoB) were synthesized and tested for the neuroprotective effect in 6-OHDA induced Parkinson disease models in vitro and in vivo.Briefly,zebrafish larvae were co-exposed to 6-OHDA and various doses of the peptides;then,dopaminergic(DA) neurons immunoreactivity and locomotion behavior of the zebrafish larvae were examined.Similarly,PC12 cells were cultured with 6-OHDA in the absence or presence of different concentrations of peptides.Cell viability was determined by MTT assay while calcium flow in the PC12 cells was monitored by Fluo-4 fluorescent dye.RESULTS Compared with control group,6-OHDA treatment could lead to DA neurons loss and locomotion deficits in PD model of zebrafish larvae(P<0.01).Both PcS hK 1(2.5,5.0 and 7.5 μmol·L^(-1)) and PcS hK 1-RhoB(0.50 and 0.75 μmol·L^(-1)) were found to protect and restore dopaminergic neurons from6-OHDA mediated injury and locomotion deficiency in the PD zebrafish respectively(P<0.01).In addition,PcShK1(2.5 to 20.0 μmol·L^(-1)) and PcShK1-RhoB(0.6 to 2.5 μmol·L^(-1)) effectively prevented against 6-OHDA toxicity in PC12 cells(P<0.01).Further study revealed that they might exert their neuroprotective effects through regulating the calcium homeostasis.CONCLUSION PcS hK 1 and PcS hK 1-RhoB show neuroprotective effects on 6-OHDA induced PD models,and the underlying protective mechanisms of these peptides probably involve calcium homeostasis regulation.