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1.  Assessment of Anti-TNF-α Activities in Keratinocytes Expressing Inducible TNF- α: A Novel Tool for Anti-TNF-α Drug Screening 
PLoS ONE  2016;11(7):e0159151.
Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine important in normal and pathological biological processes. Newly synthesized pro-TNF-α is expressed on the plasma membrane and cleaved to release soluble TNF-α protein: both are biologically active. Secreted TNF-α signals through TNF receptors and the membrane-bound TNF-α acts by cell contact-dependent signaling. Anti-TNF-α antibodies have been used effectively for treatment of chronic inflammation, however with adverse side effects. Thus, there is a need for new anti-TNF-α small molecule compounds. Anti-TNF-α activity assays involve treatment of keratinocytes with exogenous TNF-α before or after anti-TNF-α incubation. However, this model fails to address the dual signaling of TNF-α. Here we describe a Doxycycline (Dox)-inducible TNF-α (HaCaT-TNF-α) expression system in keratinocytes. Using this in-vitro model, we show cell inhibition and induced expression of pro-inflammatory cytokines and markers, including IL-1β, IL-6, IL-8, NF-κB1, and KRT-16, similar to cells treated with exogenous TNF-α. Sufficient secreted TNF-α produced also activated IL-1β and IL-8 expression in wt HaCaT cells. Importantly, stimulated expression of IL-1β and IL-8 in HaCaT-TNF-α were blocked by Quercetin, a flavanol shown to possess anti-TNF-α activities. This novel in vitro cell model provides an efficient tool to investigate the dual signaling of TNF-α. Importantly, this model provides an effective, fast, and simple screening for compounds with anti-TNF-α activities for chronic inflammatory disease therapies.
PMCID: PMC4945017  PMID: 27415000
2.  Protective Effect of Mangifera indica Linn., Cocos nucifera Linn., and Averrhoa carambola Linn. Extracts against Ultraviolet B-Induced Damage in Human Keratinocytes 
This study was aimed at investigating the antioxidant activity of Mangifera indica Linn., Cocos nucifera Linn., and Averrhoa carambola Linn. and their biological effect on human keratinocytes affected by the ultraviolet B (UVB), a major cause of cell damage and skin cancer through induction of DNA damage, production of reactive oxygen species (ROS), and apoptosis. The richest antioxidant activity was found in ethanol fraction of M. indica (21.32 ± 0.66 mg QE/g dry weight), while the lowest one was found in aqueous fractions of M. indica and C. nucifera (1.76 ± 2.10 and 1.65 ± 0.38 mg QE/g dry weight, respectively). Ethanol and aqueous fractions of A. carambola (250 µg/mL) significantly reduced the number of apoptotic cells. The expression of cleaved caspase 3 in UVB-treated group was significantly greater than that in untreated group. Both fractions of A. carambola (50, 100, and 250 µg/mL) significantly decreased the expression of cleaved caspase 3. Regarding the induction of DNA repair, ethanol (100 and 250 µg/mL) and aqueous (50, 100 and 250 µg/mL) fractions of A. carambola significantly decreased the percentage of cyclobutane pyrimidine dimers (CPD). Taken together, our results suggest that both fractions of A. carambola may be potentially developed for dermal applications.
PMCID: PMC4804050  PMID: 27057195
3.  Effect of Gloriosa superba and Catharanthus roseus Extracts on IFN-γ-Induced Keratin 17 Expression in HaCaT Human Keratinocytes 
Gloriosa superba and Catharanthus roseus are useful in traditional medicine for treatment of various skin diseases and cancer. However, their molecular effect on psoriasis has not been investigated. In this study, the effect of ethanol extracts derived from G. superba leaves and C. roseus stems on the expression of psoriatic marker, keratin 17 (K17), was investigated in human keratinocytes using biochemical and molecular experimental approaches. Both extracts could reduce the expression of K17 in a dose-dependent manner through JAK/STAT pathway as demonstrated by an observation of reduced phosphorylation of STAT3 (p-STAT3). The inhibitory activity of G. superba extract was more potent than that of C. roseus. The Pearson's correlation between K17 and cell viability was shown positive. Taken together, the extracts of G. superba and C. roseus may be developed as alternative therapies for psoriasis.
PMCID: PMC4243713  PMID: 25435888
4.  Amyloidosis in Alzheimer's Disease: The Toxicity of Amyloid Beta (Aβ), Mechanisms of Its Accumulation and Implications of Medicinal Plants for Therapy 
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that leads to memory deficits and death. While the number of individuals with AD is rising each year due to the longer life expectancy worldwide, current therapy can only somewhat relieve the symptoms of AD. There is no proven medication to cure or prevent the disease, possibly due to a lack of knowledge regarding the molecular mechanisms underlying disease pathogenesis. Most previous studies have accepted the “amyloid hypothesis,” in which the neuropathogenesis of AD is believed to be triggered by the accumulation of the toxic amyloid beta (Aβ) protein in the central nervous system (CNS). Lately, knowledge that may be critical to unraveling the hidden pathogenic pathway of AD has been revealed. This review concentrates on the toxicity of Aβ and the mechanism of accumulation of this toxic protein in the brain of individuals with AD and also summarizes recent advances in the study of these accumulation mechanisms together with the role of herbal medicines that could facilitate the development of more effective therapeutic and preventive strategies.
PMCID: PMC3671299  PMID: 23762130
5.  Are religious beliefs and practices of Buddhism associated with disability and salivary cortisol in office workers with chronic low back pain? 
Low back pain (LBP) is common among office workers. A number of studies have established a relationship between Christianity and physical and mental health outcomes among chronic pain patients. The purpose of this study was to examine the relationship between the religious beliefs and practices of Buddhism and disability and psychological stress in office workers with chronic LBP.
A cross-sectional survey was conducted with a self-administered questionnaire delivered by hand to 463 office workers with chronic LBP. Saliva samples were collected from a randomly selected sub-sample of respondents (n=96). Disability due to LBP was assessed using the Roland-Morris Disability Questionnaire and psychological stress was assessed based on salivary cortisol. Two hierarchical regression models were built to determine how much variance in disability and psychological stress could be explained by religious beliefs and practices of Buddhism variables after controlling for potential confounder variables.
Only 6% of variance in psychological stress was accounted for by the religious beliefs and practices of Buddhism. Those with high religiousness experienced lower psychological stress. No association between the religious beliefs and practices of Buddhism and disability level was found. Depressive symptoms were attributed to both psychological stress and disability status in our study population.
The findings suggest that, although being religious may improve the psychological condition in workers with chronic LBP, its effect is insufficient to reduce disability due to illness. Further research should examine the role of depression as a mediator of the effect of psychological stress on disability in patients with chronic LBP.
PMCID: PMC3554421  PMID: 23324474
6.  Acceleration of gene transfection efficiency in neuroblastoma cells through polyethyleneimine/poly(methyl methacrylate) core-shell magnetic nanoparticles 
The purpose of this study was to demonstrate the potential of magnetic poly(methyl methacrylate) (PMMA) core/polyethyleneimine (PEI) shell (mag-PEI) nanoparticles, which possess high saturation magnetization for gene delivery. By using mag-PEI nanoparticles as a gene carrier, this study focused on evaluation of transfection efficiency under magnetic induction. The potential role of this newly synthesized nanosphere for therapeutic delivery of the tryptophan hydroxylase-2 (TPH-2) gene was also investigated in cultured neuronal LAN-5 cells.
The mag-PEI nanoparticles were prepared by one-step emulsifier-free emulsion polymerization, generating highly loaded and monodispersed magnetic polymeric nanoparticles bearing an amine group. The physicochemical properties of the mag-PEI nanoparticles and DNA-bound mag-PEI nanoparticles were investigated using the gel retardation assay, atomic force microscopy, and zeta size measurements. The gene transfection efficiencies of mag-PEI nanoparticles were evaluated at different transfection times. Confocal laser scanning microscopy confirmed intracellular uptake of the magnetoplex. The optimal conditions for transfection of TPH-2 were selected for therapeutic gene transfection. We isolated the TPH-2 gene from the total RNA of the human medulla oblongata and cloned it into an expression vector. The plasmid containing TPH-2 was subsequently bound onto the surfaces of the mag-PEI nanoparticles via electrostatic interaction. Finally, the mag-PEI nanoparticle magnetoplex was delivered into LAN-5 cells. Reverse-transcriptase polymerase chain reaction was performed to evaluate TPH-2 expression in a quantitative manner.
The study demonstrated the role of newly synthesized high-magnetization mag-PEI nanoparticles for gene transfection in vitro. The expression signals of a model gene, luciferase, and a therapeutic gene, TPH-2, were enhanced under magnetic-assisted transfection. An in vitro study in neuronal cells confirmed that using mag-PEI nanoparticles as a DNA carrier for gene delivery provided high transfection efficiency with low cytotoxicity.
The mag-PEI nanoparticle is a promising alternative gene transfection reagent due to its ease of use, effectiveness, and low cellular toxicity. The mag-PEI nanoparticle is not only practical for gene transfection in cultured neuronal cells but may also be suitable for transfection in other cells as well.
PMCID: PMC3373300  PMID: 22701321
magnetic nanoparticle; non-viral vector; gene delivery; tryptophan hydroxylase-2; LAN-5; neuronal cells
7.  Rhinacanthus nasutus Extracts Prevent Glutamate and Amyloid-β Neurotoxicity in HT-22 Mouse Hippocampal Cells: Possible Active Compounds Include Lupeol, Stigmasterol and β-Sitosterol 
The Herb Rhinacanthus nasutus (L.) Kurz, which is native to Thailand and Southeast Asia, has become known for its antioxidant properties. Neuronal loss in a number of diseases including Alzheimer’s disease is thought to result, in part, from oxidative stress. Glutamate causes cell death in the mouse hippocampal cell line, HT-22, by unbalancing redox homeostasis, brought about by a reduction in glutathione levels, and amyloid-β has been shown to induce reactive oxygen species (ROS) production. Here in, we show that ethanol extracts of R. nasutus leaf and root are capable of dose dependently attenuating the neuron cell death caused by both glutamate and amyloid-β treatment. We used free radical scavenging assays to measure the extracts antioxidant activities and as well as quantifying phenolic, flavonoid and sterol content. Molecules found in R. nasutus, lupeol, stigmasterol and β-sitosterol are protective against glutamate toxicity.
PMCID: PMC3344267  PMID: 22606031
Alzheimer’s disease; glutamate; amyloid-β; neuron degeneration; oxidative stress; herbal medicine
8.  Modulation of Human Serotonin Transporter Expression by 5-HTTLPR in Colon Cells 
Serotonin (5-HT) is a monoamine neurotransmitter and plays important roles in several of the human body’s systems. Known as a primary target for psychoactive drug development, the 5-HT transporter (5-HTT, SERT) plays a critical role in the regulation of serotonergic function by reuptaking 5-HT. The allelic variation of 5-HTT expression is caused by functional gene promoter polymorphism with two principal variant alleles, 5-HTT gene-linked polymorphic region (5-HTTLPR). It has been demonstrated that 5-HTTLPR is associated with numerous neuropsychiatric disorders. The functional roles of 5-HTTLPR have been reported in human choriocarcinoma (JAR), lymphoblast and raphe cells. To date, the significance of 5-HTTLPR in gastrointestinal tract-derived cells has never been elucidated. Thus, the impact of 5-HTTLPR on 5-HTT transcription was studied in SW480 human colon carcinoma cells, which were shown to express 5-HTT. We found 42-bp fragment in long (L) allele as compared to short (S) allele, and this allelic difference resulted in 2-fold higher transcriptional efficiency of L allele (P < 0.05) as demonstrated using a functional reporter gene assay. Nevertheless, the transcriptional effect of estrogen and glucocorticoid on 5-HTT expression via 5-HTTLPR was not found in this cell line. Our study was the first to demonstrate the molecular role of this allelic variation in gastrointestinal tract cells.
PMCID: PMC3210998  PMID: 22072907
serotonin transporter; allelic variation; transcriptional regulation; promoter; hormonal effect; gastrointestinal tract cells

Results 1-8 (8)