Statins, the inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are widely used cholesterol-lowering drugs. Convincing evidence indicates that statins stimulate apoptotic cell death in several types of proliferating tumor cells in a cholesterol-lowering-independent manner. The objective here was to elucidate the molecular mechanism by which statins induce lymphoma cells death. Statins (atorvastatin, fluvastatin and simvastatin) treatment enhanced the DNA fragmentation and the activation of proapoptotic members such as caspase-3, PARP and Bax, but suppressed the activation of anti-apoptotic molecule Bcl-2 in lymphoma cells including A20 and EL4 cells, which was accompanied by inhibition of cell survival. Both increase in levels of reactive oxygen species (ROS) and activation of p38 MAPK and decrease in mitochondrial membrane potential and activation of Akt and Erk pathways were observed in statin-treated lymphoma cells. Statin-induced cytotoxic effects, DNA fragmentation and changes of activation of caspase-3, Akt, Erk and p38 were blocked by antioxidant (N-acetylcysteine) and metabolic products of the HMG-CoA reductase reaction, such as mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP). These results suggests that HMG-CoA reductase inhibitors induce lymphoma cells apoptosis by increasing intracellular ROS generation and p38 activation and suppressing activation of Akt and Erk pathways, through inhibition of metabolic products of the HMG-CoA reductase reaction including mevalonate, FPP and GGPP.

Background: Titanium dioxide nanoparticles (TiO₂ NPs) represent a scientific breakthrough in the areas of biological and medicinal applications. Interaction of TiO₂ NPs with components of innate immune system remains elusive. Aim: This study explored in vitro immunotoxicity of murine macrophage RAW 264.7 to TiO₂ NPs (20 nm, negative charge) and its underlying molecular mechanism by way of immunoredox profiling. Materials and methods: In this study, chemically synthesized BSA-functionalized TiO₂ NPs (20 nm, negative charge) were characterized and immunotoxicity was investigated on RAW 264.7 cells. Results: We found that reactive oxygen species levels significantly increased with increasing nitric oxide production, whereas depleting endogenous antioxidant super oxide dismutase as well as nuclear factor erythroid 2-related factor 2 (Nrf2) protein levels. Furthermore, NPs exposure increased the expression of apoptotic factors such as BAX, BIM, and PUMA with disruption of mitochondrial membrane potential (ΔΨ_m) that lead to decrease in immunocytes. Molecular immune profiling revealed the activation of multiple toll-like receptors (TLRs) 4/9/12/13 simultaneously with the phosphorylation of p-p38MAPK and p-SAPK/c-Jun N-terminal kinase (JNK) compared to untreated control. Conclusion: Collectively, this study shows that the molecular nature of TiO₂^SA20(-) NP-induced immunotoxicity in RAW 264.7 macrophage is simultaneous induction of immunocyte apoptosis and multiple TLRs signaling through oxidative stress-dependent SAPK/JNK and p38 mitogen-associated protein kinase activation. This is the first study to address newer molecular mechanism of TiO₂^SA20(-) NP-induced immunotoxicity.

Silicon dioxide (SiO₂) nanoparticles (NPs) have been widely used in the biomedical field, such as in drug delivery and gene therapy. However, little is known about the biological effects and potential hazards of SiO₂. Herein, the colloidal SiO₂ NPs with two different sizes (20 nm and 100 nm) and different charges (L-arginine modified: SiO₂^EN20[R], SiO₂^EN100[R]; and negative: SiO2^EN20[-], SiO₂^EN100[-]) were orally administered (750 mg/kg/day) in female C57BL/6 mice for 14 days. Assessments of immunotoxicity include hematology profiling, reactive oxygen species generation and their antioxidant effect, stimulation assays for B- and T-lymphocytes, the activity of natural killer (NK) cells, and cytokine profiling. In vitro toxicity was also investigated in the RAW 264.7 cell line. When the cellularity of mouse spleen was evaluated, there was an overall decrease in the proliferation of B- and T-cells for all the groups fed with SiO₂ NPs. Specifically, the SiO₂^EN20(-) NPs showed the most pronounced reduction. In addition, the nitric oxide production and NK cell activity in SiO₂ NP-fed mice were significantly suppressed. Moreover, there was a decrease in the serum concentration of inflammatory cytokines such as interleukin (IL)-1Β, IL-12 (p70), IL-6, tumor necrosis factor-α, and interferon-γ. To elucidate the cytotoxicity mechanism of SiO₂ in vivo, an in vitro study using the RAW 264.7 cell line was performed. Both the size and charge of SiO₂ using murine macrophage RAW 264.7 cells decreased cell viability dose-dependently. Collectively, our data indicate that different sized and charged SiO₂ NPs would cause differential immunotoxicity. Interestingly, the small-sized and negatively charged SiO₂ NPs showed the most potent in vivo immunotoxicity by way of suppressing the proliferation of lymphocytes, depressing the killing activity of NK cells, and decreasing proinflammatory cytokine production, thus leading to immunosuppression.

Purpose. This study was performed to evaluate antifatigue effect of hydrogen water (HW) drinking in chronic forced exercise mice model. Materials and Methods. Twelve-week-old C57BL6 female mice were divided into nonstressed normal control (NC) group and stressed group: (purified water/PW-treated group and HW-treated group). Stressed groups were supplied with PW and HW, respectively, ad libitum and forced to swim for the stress induction every day for 4 consecutive weeks. Gross antifatigue effects of HW were assessed by swimming endurance capacity (once weekly for 4 wk), metabolic activities, and immune-redox activities. Metabolic activities such as blood glucose, lactate, glycogen, blood urea nitrogen (BUN), and lactate dehydrogenase (LDH) as well as immune-redox activities such as reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), catalase, and the related cytokines were evaluated to elucidate underlying mechanism. Blood glucose and lactate were measured at 0 wk (before swimming) and 4 wk (after swimming). Results. HW group showed a higher swimming endurance capacity (p<0.001) than NC and PW groups. Positive metabolic effects in HW group were revealed by the significant reduction of blood glucose, lactate, and BUN in serum after 4 wk (p<0.01, resp.), as well as the significant increase of liver glycogen (p<0.001) and serum LDH (p<0.05) than PW group. In parallel, redox balance was represented by lower NO in serum (p<0.01) and increased level of GPx in both serum and liver (p<0.05) than PW group. In line, the decreased levels of serum TNF-α (p<0.01), IL-6, IL-17, and liver IL-1β (p<0.05) in HW group revealed positive cytokine profile compared to PW and NC group. Conclusion. This study shows antifatigue effects of HW drinking in chronic forced swimming mice via metabolic coordination and immune-redox balance. In that context, drinking HW could be applied to the alternative and safety fluid remedy for chronic fatigue control.

While zinc oxide (ZnO) nanoparticles (NPs) have been recognized to have promising applications in biomedicine, their immunotoxicity has been inconsistent and even contradictory. To address this issue, we investigated whether ZnO NPs with different size (20 or 100 nm) and electrostatic charge (positive or negative) would cause immunotoxicity in vitro and in vivo, and explored their underlying molecular mechanism. Using Raw 264.7 cell line, we examined the immunotoxicity mechanism of ZnO NPs as cell viability. We found that in a cell viability assay, ZnO NPs with different size and charge could induce differential cytotoxicity to Raw 264.7 cells. Specifically, the positively charged ZnO NPs exerted higher cytotoxicity than the negatively charged ones. Next, to gauge systemic immunotoxicity, we assessed immune responses of C57BL/6 mice after oral administration of 750 mg/kg/day dose of ZnO NPs for 2 weeks. In parallel, ZnO NPs did not alter the cell-mediated immune response in mice but suppressed innate immunity such as natural killer cell activity. The CD4⁺/CD8⁺ ratio, a marker for matured T-cells was slightly reduced, which implies the alteration of immune status induced by ZnO NPs. Accordingly, nitric oxide production from splenocyte culture supernatant in ZnO NP-fed mice was lower than control. Consistently, serum levels of pro/anti-inflammatory (interleukin [IL]-1Β, tumor necrosis factor-α, and IL-10) and T helper-1 cytokines (interferon-γ and IL-12p70) in ZnO NP-fed mice were significantly suppressed. Collectively, our results indicate that different sized and charged ZnO NPs would cause in vitro and in vivo immunotoxicity, of which nature is an immunosuppression.

Atopic dermatitis (AD) is a chronic relapsing allergic inflammatory skin disease that currently affects millions of children and adults worldwide. Drugs used to treat these inflammatory diseases include anti-histamines, corticosteroids and calcineurin inhibitors but these drugs have their limitations such as adverse effects with their long-term usage. Thus, researcher’s interest in several alternative and complementary therapies are continually growing and balneotherapy is one of these approaches. Therefore, we investigate the bathing effect of high concentration mineral spring water (HMW) on redox balance and immune modulation in 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis like inflammation in hairless mice. We induced AD-like inflammation by application of DNCB on the dorsal skin of female skh-1 hairless mice. The mice were treated with 100% pure HMW (PHMW) and 10% diluted HMW (DHMW) through bathing once a day for 4 weeks. Tacrolimus ointment (0.1%) was used as positive control (PC) and only DNCB treatment as negative control (NeC) group. The severity of skin lesion inflammation was assessed through clinical scoring and observing scratching behavior. Levels of immunoglobulin E (IgE) and inflammatory cytokines in serum were detected by ELISA and multiplex bead array system, and the levels of oxidative stress-related biomarkers and antioxidant enzyme were also measured. We found that HMW significantly decreased the scratching behavior in PHMW and DHMW groups at the 2nd week and in PHMW group at 4th week compared to NeC group. Likewise, serum IgE level was significantly decreased in DHMW group as compared to NeC group. In line, the level of inflammatory cytokines in serum such as interleukin (IL)-1β, IL-13 and tumor necrosis factor-α were significantly inhibited in PHMW and DHMW groups compared to NeC group. In parallel, total reactive oxygen species (ROS) of serum level was significantly decreased in PHMW treatment groups compared to NeC group. Consistently, serum malondialdehyde (MDA) level in PHMW group was lower than in NeC group. By contrast, glutathione peroxidase (GPx) activity was significantly enhanced in PHMW than NeC. Collectively, our study indicates a balneotherapeutic effect of HMW on DNCB-induced AD like inflammation in hairless mice via immunomodulation and redox balance.