A novel protein kinase inhibitor IMB-YH-8 with anti-tuberculosis activity.

Protein kinase B (PknB) is one of the Mycobacterium tuberculosis serine/threonine protein kinases and has an essential role in sustaining mycobacterial growth. Here, we identified and characterized a novel small molecule compound named IMB-YH-8 that inhibited PknB and served as anti-mycobacteria lead compound. IMB-YH-8 inhibited PknB auto-phosphorylation and the phosphorylation of GarA by PknB in a dose-dependent manner. The compound did not inhibit human Akt1 or other serine/threonine kinases in M. tuberculosis except for the highly homologous PknA. IMB-YH-8 bound to PknB with a moderate affinity. Molecular docking revealed that IMB-YH-8 interacts with the catalytic domain of PknB. Observations of electron microscopy showed that IMB-YH-8 changed the morphology of H37Rv and disrupted the cell wall. The differential transcriptional response of M. tuberculosis to IMB-YH-8 revealed changes in SigH regulatory pathways modulated by PknB. Notably IMB-YH-8 not only potently inhibited drug-sensitive and multidrug-resistant clinical isolates but also exhibited a dose dependent inhibition of intracellular M. tuberculosis. Taken together, these in vitro data demonstrate that IMB-YH-8 is a novel inhibitor of PknB, which potently prevents growth of M. tuberculosis. It is as yet unclear whether inhibition of PknA contributes to the anti-tubercular action of IMB-YH-8.

Dalbergioidin (DAL) protects MC3T3-E1 osteoblastic cells against H2O2-induced cell damage through activation of the PI3K/AKT/SMAD1 pathway.

Reactive oxygen species (ROS) is a pivotal pathogenic factor in the development of osteoporosis. Dalbergioidin (DAL) can be isolated from Uraria crinite, an edible herb used as a natural food for childhood skeletal dysplasia. Recent research has implicated DAL as having an antiosteoporosis effect, although the mechanism of this is unclear. We used an effective oxidative stress model, induced by hydrogen peroxide (H2O2) in osteoblastic MC3T3-E1 cells, to investigate the protective effects of DAL in osteoporosis and the underlying molecular mechanisms. The results indicated that treatment with DAL maintained redox balance, reduced MC3T3-E1 cell apoptosis, improved alkaline phosphatase activity, and elevated the osteogenic-related protein expression of Runx2, Osterix, and BMP2 against oxidative damage induced by H2O2. The potential molecular mechanism involved in the protective effect of DAL against H2O2-induced cell death in MC3T3-E1 cells may lie in the activation of the PI3K/AKT/SMAD1 cell signal pathway. Taken together, the results indicated that the potential protective effects of DAL against osteoporosis were linked to a reduction in oxidative damage, suggesting that DAL may be useful in bone metabolism diseases, particularly osteoporosis.

Longikaurin E induces apoptosis of pancreatic cancer cells via modulation of the p38 and PI3K/AKT pathways by ROS.

Pancreatic cancer is a devastating disease with a poor prognosis. It ranks as the fourth or fifth most common cancer in men and women and has the lowest 5-year survival rate. Therefore, there is an urgent need to develop novel therapeutic agents for pancreatic cancer. Longikaurin E (LE), which is derived from the traditional herbal medicine Rabdosia longituba, had been reported to have anti-proliferative and pro-apoptotic properties in several types of cancers. In this study, we investigated the cytotoxic properties of LE against pancreatic cancer cells and explored the mechanism behind the observed apoptosis. Pancreatic cancer cell lines cultured in the presence of LE exhibited dose- and time-dependent growth suppression by clone formation, methylthiazoltetrazolium assay, lactate dehydrogenase cytotoxicity assay, and fluorescence-activated cell sorting analysis, respectively. In addition, these culture conditions also induced the generation of cellular reactive oxygen species (ROS). In order to determine the mechanisms underlying LE-induced cytotoxicity, we used reverse transcription polymerase chain reaction and Western blot analysis in the pancreatic cancer cell line PANC1. The results showed that the expression of Bax was noticeably upregulated and the expression levels of Bcl-2, Bcl-XL, survivin, and c-Myc were significantly downregulated. We also observed increased p38 phosphorylation and decreased phosphorylation of the PI3K/AKT pathway. Interestingly, we also found that LE activated caspase-3. However, N-acetyl-L-cysteine, a kind of antioxidant, reversed all of these cellular activities. In conclusion, this study suggested that LE induced apoptosis of pancreatic cancer cells via ROS generation to modulate the p38 and PI3K/AKT pathways and could be a promising anti-pancreatic agent.

Synthesis and cytotoxic evaluation of alkoxylated chalcones.

A series of chalcones a1-20 bearing a 4-OMe groups on the A-ring were initially synthesized and their anticancer activities towards HepG2 cells evaluated. Subsequently, a series of chalcones b1-42 bearing methoxy groups at the 2' and 6'-positions of the B-ring were synthesized and their anticancer activities towards five human cancer cell lines (HepG2, HeLa, MCF-7, A549 and SW1990) and two non-tumoral human cell lines evaluated. The results showed that six compounds (b6, b8, b11, b16, b18, b22, b23 and b29) displayed promising activities, with compounds b22 and b29 in particular showing higher levels of activity than etoposide against all five cancer cell lines. Compound b29 showed a promising SI value compared with both HMLE and L02 (2.1-6.5 fold in HMLE and > 33 > 103.1 fold in L02, respectively).

Neuroprotective effects of madecassoside in early stage of Parkinson's disease induced by MPTP in rats.

In this study, we investigated the neuroprotective effects of madecassoside, isolated from the Chinese medicinal herb Centella asiatica, in the rat model of early phase of parkinsonism. During intragastric administrations of madecassoside for 7 days, the rats were injected with MPTP on the 7th day. And for the following 14 days, madecassoside were also administered. On the 14th day, the behavioral tests were assessed after 1h of administration. And then, the rats were sacrificed, substantia nigra and striatum were dissected. The content of DA, MDA, GSH, and Bcl-2/Bax gene expression levels and BDNF protein level was determined. Treatment with madecassoside was found to improve locomotor dysfunction and to protect dopaminergic neuron by antagonizing MPTP induced neurotoxicity. Madecassoside significantly attenuated the MPTP-induced reduction of dopamine in the striatum. The MDA contents were significantly decreased while the GSH levels, Bcl-2/Bax ratio and protein expression of BDNF were significantly increased in madecassoside treated groups. These results indicated that madecassoside was effective in recovering MPTP-induced early signs of parkinsonism via its neuroprotective effects including reversing the depletion of DA, antioxidant activity, increasing ratio of Bcl-2/Bax, increasing protein expression of BDNF.

Arylsulfonylamino-benzanilides as inhibitors of the apical sodium-dependent bile salt transporter (SLC10A2).

The apical sodium-dependent bile salt transporter (ASBT) plays a pivotal role in maintaining bile acid homeostasis. Inhibition of ASBT would reduce bile acid pool size and lower cholesterol levels. In this report, a series of novel arylsulfonylaminobenzanilides were designed and synthesized as potential inhibitors of ASBT. Most of them demonstrated great potency against ASBT's bile acid transport activity. In particular, compound 5g2 inhibited ASBT activity with an IC50 value of 0.11 µM. These compounds represent potential cholesterol-lowering drugs.

Antidepressant-like effect of magnolol on BDNF up-regulation and serotonergic system activity in unpredictable chronic mild stress treated rats.

Magnolol is the main constituent identified in the barks of Magnolia officinalis, which has been used for the treatment of mental disorders including depression in China. In this study, we investigated the antidepressant-like effect of magnolol, and its possible mechanisms in rats subjected to unpredictable chronic mild stress (UCMS). High performance liquid chromatography with electrochemical detection (HPLC-ECD) and immunohistochemical staining analysis were applied to explore the mechanisms underlying the antidepressant-like effect of magnolol. Magnolol (20, 40 mg/kg) significantly reversed UCMS-induced reduction in sucrose consumption and deficiency in locomotor activity. In addition, it was observed that administration of magnolol (20, 40 mg/kg) restored brain-derived neurotrophic factor (BDNF) expression, and normalized the serotonergic system changes in the UCMS-treated rats. These results confirmed the antidepressant-like effect of magnolol, which might be based primarily on its ability to increase the BDNF expression and enhance the activity of the serotonergic system in rat brains.

Asiaticoside: attenuation of neurotoxicity induced by MPTP in a rat model of Parkinsonism via maintaining redox balance and up-regulating the ratio of Bcl-2/Bax.

In this study, we investigated the neuroprotective effects of asiaticoside, a triterpenoid saponin isolated from the Chinese medicinal herb Centella asiatica, in the rats model of Parkinsonism induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Rats were first injected with MPTP. One day after surgery, asiaticoside was administered and the behavioral tests were assessed. On 14th day, the rats were sacrificed, substantia nigra (SN) and striatum were dissected, and then dopamine (DA) and its metabolites in striatum and malonyldialdehyde (MDA) contents, reduced glutathione (GSH) level and gene expression level in SN were estimated. Treatment with asiaticoside was found to protect dopaminergic neuron by antagonizing MPTP induced neurotoxicity and to improve locomotor dysfunction. Asiaticoside significantly attenuated the MPTP-induced reduction of dopamine in the striatum. The content of MDA was significantly decreased while the GSH level was significantly increased in asiaticoside-treated groups. In addition, asiaticoside increased the Bcl-2/Bax ratio. These results indicated that asiaticoside was effective in reversing MPTP induced Parkinsonism via its neuroprotective effects including antioxidant activity, maintaining the metabolic balance of DA, and increasing ratio of Bcl-2/Bax.

Antidepressant-like effects of the saponins extracted from Chaihu-jia-longgu-muli-tang in a rat unpredictable chronic mild stress model.

Chaihu-jia-longgu-muli-tang (CLM) has been used for treating depressive disorders for thousands of years in China. In the present study, we investigated the antidepressant-like effect of the saponins extracted from CLM (SCLM) in rats subjected to unpredictable chronic mild stress (UCMS). The ameliorative effect of SCLM on symptom of depression through behavior tests including: sucrose preference test, open-field test and forced-swimming test was investigated. In addition, high performance liquid chromatography with electrochemical detection (HPLC-ECD), immunohistochemical staining analysis and RT-PCR were applied to explore the mechanisms underlying the antidepressant-like effects of SCLM. It was observed that administration of SCLM (70, 140 mg/kg) reversed the depressive-like behaviors, restored the reduction in the levels of monoamine neurotransmitters and up-regulated the expression of brain-derived neurotrophic factor (BDNF) in UCMS-treated rats. These findings confirmed the antidepressant-like effects of SCLM in UCMS model of rats.

Protective effect of Zhen-Wu-Tang (ZWT) through keeping DA stable and VMAT 2/DAT mRNA in balance in rats with striatal lesions induced by MPTP.

ETHNOPHARMACOLOGICAL RELEVANCE: Zhen-Wu-Tang (ZWT), the modified formulation of a classical Chinese prescription from "Treaties on Febrile Disease", was clinically employed to treat Parkinson's disease. AIM OF THE STUDY: To investigate the neuroprotective effect of ZWT on intra-striatum injection of MPTP-induced Parkinson's disease in rats. MATERIALS AND METHODS: The effect of ZWT on the behavioral changes (open-field test, Ladder walking, spontaneous alternation in Y maze), the dopamine transmitter systems of substantia nigra, striatum and frontal cortex of rats by HPLC-ECD, mRNA expression of tyrosine hydroxylase (TH), dopamine transporter (DAT) and vesicular monoamine transporter 2 (VMAT 2) of the above three brain regions was investigated. RESULTS: This study showed that ZWT not only ameliorated the behavior induced by the administration of MPTP in striatum, but also increased DA in the brain, prevented the decreasing of TH and balanced the ratio of VMAT 2/DAT in mRNA level. CONCLUSIONS: These results suggest that ZWT possesses neuroprotective and anti-parkinsonism properties.

Effects of SMYD3 over-expression on cell cycle acceleration and cell proliferation in MDA-MB-231 human breast cancer cells.

SET and MYND domain-containing protein 3 (SMYD3) is a histone methyltransferase that plays an important role in transcriptional regulation in human carcinogenesis. It can specifically methylate histone H3 at lysine 4 and activate the transcription of a set of downstream genes, including several oncogenes (e.g., N-myc, CrkL, Wnt10b, RIZ and hTERT) and genes involved in the control of cell cycle (e.g., CyclinG1 and CDK2) and signal transduction (e.g., STAT1, MAP3K11 and PIK3CB). To determine the effects of SMYD3 over-expression on cell proliferation, we transfected SMYD3 into MDA-MB-231 cells and found that these cells showed several transformed phenotypes as demonstrated by colony growth in soft agar. Besides, we show here that down-regulation of SMYD3 could induce G1-phase cell cycle arrest, indicating the potent induction of apoptosis by SMYD3 knockdown. These results suggest the regulatory mechanisms of SMYD3 on the acceleration of cell cycle and facilitate the development of strategies that may inhibit the progression of cell cycle in breast cancer cells.

Ameliorative and neuroprotective effect in MPTP model of Parkinson's disease by Zhen-Wu-Tang (ZWT), a traditional Chinese medicine.

AIM OF THE STUDY: Traditional Chinese medicine Zhen-Wu-Tang (ZWT) is a well-known PentaHerbs formula from "Treatise on Febrile Disease". This study is to elucidate its neuroprotective effect and mechanism of ameliorative effect of the syndrome of Parkinson's disease (PD). MATERIALS AND METHODS: The ameliorative effect of ZWT on symptom of PD through behavior tests including: swimming test, the tail suspension test and open-field test was investigated. The neuroprotective effect of dopaminergic neurons from the striatum and frontal cortex of brain was detected by high performance liquid chromatography with electrochemical detection (HPLC-ECD). RESULTS: This study proved that ZWT could ameliorate the typical symptom of PD and protect dopaminergic system. CONCLUSION: These results suggested that ZWT possessed protective and ameliorative properties of dopaminergic neurons.

Synthesis, structure, texture, and CO sensing behavior of nanocrystalline tin oxide doped with scandia.

Weakly agglomerated nanocrystalline scandia doped tin oxide powders with high surface area (170-220 m(2)/g) and uniform size (3-4 nm) were synthesized for the first time by a two-step hydrothermal process in the presence of urea, followed by the calcination between 500 and 1200 degrees C. The structure and texture of the binary oxide system were characterized by thermogravimetry and differential thermal analysis, Brunauer-Emmett-Teller-specific surface area analysis, transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. A metastable scandium tin oxide solid solution in tetragonal structure was formed for the scandia content lower than 6 mol % as the samples were calcined at 800 degrees C, and the excess Sc atoms were dispersed at the surface of the crystallites above this limit. The solid solution was metastable, so scandium migrated toward the surface region of the crystallites and produced a second phase of Sc(4)Sn(3)O(12) during calcining at high temperatures over 1000-1200 degrees C. In the case of the samples with higher dopant concentration (>15 mol %), the calcination at the temperature between 500 and 800 degrees C caused the precipitation of Sc(2)O(3), and the calcination over 1000-1200 degrees C led to the formation of more Sc(4)Sn(3)O(12). Textural analysis showed that doping an appropriate amount of Sc(2)O(3) into nanosized SnO(2) could effectively inhibit the grain growth and stabilize the surface area against high-temperature calcinations below 1000 degrees C. CO gas-sensing property measurements revealed that the dispersion of Sc at the surfaces of the SnO(2) nanocrystallites could improve the CO sensitivity significantly, and the pellet sample with scandia content of 10 mol % sintered at 800 degrees C showed the best CO gas-sensing property in the operation temperature range of 300-400 degrees C. On the basis of the structural and textural analysis, the correlation between the structure/texture and the sensitivity to CO for the as-calcined (SnO(2))(1-x)(Sc(2)O(3))(x) nanocrystallites has been established and explained.