Encephalitis has been described worldwide as a severe complication in patients infected by dengue virus. Reactive oxygen species (ROS) production is a key mechanism involved in the neuronal damage caused by viral encephalitis. In the present study, the capability of dengue virus serotypes 2 (DENV2) and DENV4 to induce ROS production was investigated in a rat microglial cell line, HAPI cells. The cells were infected with DENV2 and DENV4 at a multiplicity of infection of 0.1 for a 2-h adsorption period. Japanese encephalitis virus (JEV) was used as the reference. DENV2- and DENV4-induced microglial activation and significantly increased ROS production corresponded to decreased cell viability. The activity of DENV4 was significantly higher than the activities of DENV2 and JEV at 48 and 72 h post infection. DENV4 partly induced ROS production via an iron-induced Fenton reaction, as demonstrated by the treatment with an iron chelator, deferiprone. Despite the induction of increased inducible nitric oxide synthase expression and nitric oxide (NO) production by JEV, DENV2, and DENV4 did not induce NO production, suggesting the activation of different pathways in response to infections by different viruses. In conclusion, DENV2 and DENV4 have the capability to induce ROS production and activate microglia, which have been reported as the key components of neuronal damage.

Microglial activation has been found to play a crucial role in various neurological disorders. Proinflammatory substances overproduced by activated microglia, such as cytokines, chemokines, reactive oxygen species, and nitric oxide (NO), can result in neuroinflammation that further exacerbates the course of the diseases. This study aimed to explore the anti-inflammatory effect of the ethyl acetate extract of Pueraria mirifica on microglial activation. Lipopolysaccharide (LPS)-induced inflammation was used as a model to investigate the effects of P. mirifica on HAPI (highly aggressive proliferating immortalized), a rat microglial cell line. Administration of ethyl acetate extract from the tuberous roots of P. mirifica to HAPI cells dose-dependently reduced NO production and iNOS expression induced by LPS. Attenuation of IRF-1 (interferon regulatory factor-1) induction, one of the transcription factors governing iNOS expression, suggested that the inhibitory effect on NO production by the plant extract was at least partially mediated through this transcription factor. In addition, LPS-stimulated mRNA expression of MCP-1 (monocyte chemoattractant protein-1), IL-6 (interleukin-6), and TNF-α (tumor necrosis factor-α) was also suppressed with P. mirifica extract pretreatment. This study indicates that the ethyl acetate extract of P. mirifica could potentially serve as an anti-inflammatory mediator and may be useful in relieving the severity of neurological diseases where microglia play a role.

Cholangiocarcinoma (CCA) is a difficult-to-treat cancer, with limited therapeutic options and surgery being the only curative treatment. Standard chemotherapy involves gemcitabine-based therapies combined with cisplatin, oxaliplatin, capecitabine, or 5-FU with a dismal prognosis for most patients. Receptor tyrosine kinases (RTKs) are aberrantly expressed in CCAs encompassing potential therapeutic opportunity. Hence, 112 RTK inhibitors were screened in KKU-M213 cells, and ceritinib, an approved targeted therapy for ALK-fusion gene driven cancers, was the most potent candidate. Ceritinib’s cytotoxicity in CCA was assessed using MTT and clonogenic assays, along with immunofluorescence, western blot, and qRT-PCR techniques to analyze gene expression and signaling changes. Furthermore, the drug interaction relationship between ceritinib and cisplatin was determined using a ZIP synergy score. Additionally, spheroid and xenograft models were employed to investigate the efficacy of ceritinib in vivo. Our study revealed that ceritinib effectively killed CCA cells at clinically relevant plasma concentrations, irrespective of ALK expression or mutation status. Ceritinib modulated multiple signaling pathways leading to the inhibition of the PI3K/Akt/mTOR pathway and activated both apoptosis and autophagy. Additionally, ceritinib and cisplatin synergistically reduced CCA cell viability. Our data show ceritinib as an effective treatment of CCA, which could be potentially explored in the other cancer types without ALK mutations.

Oxidative stress plays a pivotal role in several human diseases including Parkinson’s disease (PD). Curcuma comosa, a member of Zingiberaceae, is widely known in Thailand as an alternative medicinal herb for uterine inflammation and estrogenic properties. In this study (3S)-1-(3,4-dihydroxyphenyl)-7-phenyl-(6E)-6-hepten-3-ol or compound 092 (C-092, or ASPP 092), a pure compound isolated from ethanol extract of C. comosa, was evaluated for neuroprotective effect on hydrogen peroxide-induced toxicity in SH-SY5Y cells. C-092 demonstrated a radical scavenging effect with comparable efficacy to ascorbic acid and exhibited a neuroprotective effect via suppression of apoptotic cell death as evidenced by a reduction in phospho-p53 and cleaved caspase-3 expression. C-092 causes induction of Nrf-2, which is a transcription factor responsible for the expression of a range of antioxidant genes. Moreover, the reduction in catalase activity caused by hydrogen peroxide was also alleviated by C-092 treatment. These results suggested the therapeutic potential of this compound for neurodegenerative diseases caused by oxidative stress.

Objective: We investigated the molecular mechanisms underlying the effect of (3S)-1-(3,4-dihydroxyphenyl)-7-phenyl-(6E)-6-hepten-3-ol, also known as compound 092, isolated from Curcuma comosa Roxb on the production of pro-inflammatory mediators and oxidative stress in lipopolysaccharide (LPS)-activated highly aggressive proliferating immortalized (HAPI) microglial cell lines. Method: Nitric oxide (NO) production was determined using the Griess reaction, and reverse transcription polymerase chain reaction was used to measure the expression of inducible nitric oxide synthase (iNOS) mRNA. Western blotting was used to determine the levels of pro-inflammatory mediators and their related upstream proteins. Key finding: Compound 092 suppressed NO production and iNOS expression in LPS-stimulated HAPI cells. These effects originated from the ability of compound 092 to attenuate the activation of nuclear factor (NF)-κB as determined by the reduction in p-NF-κB and p-IκB kinase (IKK) protein levels. Compound 092 also significantly lowered LPS-activated intracellular reactive oxygen species production and p38 mitogen-activated protein kinase (MAPK) activation. Conclusion: Compound 092 suppresses microglial activation through attenuation of p38 MAPK and NF-κB activation. Compound 092 thus holds the potential to treat neurodegenerative disorders associated with neuroinflammation and oxidative stress.