Myostatin inhibitor YK11 as a preventative health supplement for bacterial sepsis.

Muscle wasting caused by catabolic reactions in skeletal muscle is commonly observed in patients with sepsis. Myostatin, a negative regulator of muscle mass, has been reported to be upregulated in diseases associated with muscle atrophy. However, the behavior of myostatin during sepsis is not well understood. Herein, we sought to investigate the expression and regulation of myostatin in skeletal muscle in mice inoculated with gram-negative bacteria. Interestingly, the protein level of myostatin was found to increase in the muscle of septic mice simultaneously with an increase in the levels of follistatin, NF-κΒ, myogenin, MyoD, p- FOXO3a, and p-Smad2. Furthermore, the inhibition of myostatin by YK11 repressed the levels of pro-inflammatory cytokines and organ damage markers in the bloodstream and in the major organs of mice, which originally increased in sepsis; thus, myostatin inhibition by YK11 decreased the mortality rate due to sepsis. The results of this study suggest that YK11 may help revert muscle wasting during sepsis and subdue the inflammatory environment, thereby highlighting its potential as a preventive agent for sepsis-related muscle wasting.

Platelet-activating Factor Mediates Endotoxin Tolerance by Regulating Indoleamine 2,3-Dioxygenase-dependent Expression of the Suppressor of Cytokine Signaling 3.

Indoleamine 2,3-dioxygenase (IDO) mediates immune tolerance, and suppressor of cytokine signaling 3 (SOCS3) negatively regulates the JAK/STAT signal transduction pathway. We determined previously that platelet-activating factor (PAF) protects mice against LPS-induced endotoxic shock, but its detailed mechanism of action was unknown. We performed survival experiments in IDO+/+ and IDO-/- mice using an LPS-induced endotoxemia model and rated organ injury (neutrophil infiltration and liver function). Using ELISA and Western blotting, we also investigated the mechanism of PAF-mediated endotoxin tolerance during endotoxemia. PAF-mediated endotoxin tolerance was dependent on IDO in vivo and in vitro and was not observed in IDO-/- mice. JAK/STAT signaling, crucial for SOCS3 expression, was also impaired in the absence of IDO. In an IDO- and STAT-dependent manner, PAF mediated a decrease in IL-12 and a dramatic increase in IL-10 and reduced mouse mortality. In addition, PAF attenuated LPS-mediated neutrophil infiltration into the lungs and interactions between neutrophil-like (THP-1) and endothelial cells (human umbilical vein endothelial cells). These results indicate that PAF-mediated endotoxin tolerance is initiated via IDO- and JAK/STAT-dependent expression of SOCS3. Our study has revealed a novel tolerogenic mechanism of IDO action and an important association between IDO and SOCS3 with respect to endotoxin tolerance.

Tamarixetin Exhibits Anti-inflammatory Activity and Prevents Bacterial Sepsis by Increasing IL-10 Production.

Sepsis is a systemic inflammatory response to pathogenic infection that currently has no specific pharmaceutical interventions. Instead, antibiotics administration is considered the best available option, despite increasing drug resistance. Alternative strategies are therefore urgently required to prevent sepsis and strengthen the host immune system. One such option is tamarixetin (4'- O-methylquercetin), a naturally occurring flavonoid derivative of quercetin that protects against inflammation. The purpose of this study was to determine whether the anti-inflammatory effects of tamarixetin protect against the specific inflammatory conditions induced in lipopolysaccharide (LPS) or Escherichia coli K1 models of sepsis. Our study showed that tamarixetin reduced the secretion of various inflammatory cytokines by dendritic cells after activation with LPS. It also promoted the secretion of the anti-inflammatory cytokine interleukin (IL)-10 and specifically increased the population of IL-10-secreting immune cells in LPS-activated splenocytes. Tamarixetin showed general anti-inflammatory effects in mouse models of bacterial sepsis and decreased bacteria abundance and endotoxin levels. We therefore conclude that tamarixetin has superior anti-inflammatory properties than quercetin during bacterial sepsis. This effect is associated with an increased population of IL-10-secreting immune cells and suggests that tamarixetin could serve as a specific pharmaceutical option to prevent bacterial sepsis.

Inhibitory effect of the tricyclic antidepressant amitriptyline on voltage-dependent K+ channels in rabbit coronary arterial smooth muscle cells.

Amitriptyline, a tricyclic antidepressant (TCA) drug, is widely used in treatment of psychiatric disorders. However, the side effects of amitriptyline on vascular K+ channels remain to be determined. Therefore, we investigated the effect of the tricyclic antidepressant and serotonin reuptake inhibitor amitriptyline on voltage-dependent K+ (Kv) channels in freshly isolated rabbit coronary arterial smooth muscle cells, using the whole-cell patch clamp technique. The Kv current amplitudes were inhibited by amitriptyline in a concentration-dependent manner, with an apparent IC50 value of 2.2 ± 0.14 µmol/L and a Hill coefficient of 0.87 ± 0.03. Amitriptyline shifted the activation curve to a more positive potential, but had no significant effect on the inactivation curve, suggesting that amitriptyline altered the voltage sensitivity of Kv channels. Pretreatment with Kv1.5 and Kv1.2 channel inhibitors did not alter the inhibitory effect of amitriptyline on Kv channels. Additionally, application of train pulses (1 and 2 Hz) did not affect amitriptyline-induced inhibition of Kv currents, which suggested that the action of amitriptyline on Kv channels was not use (state)-dependent. From these results, we concluded that amitriptyline inhibited the channels in a concentration-dependent, but state-independent manner.

Neoagarooligosaccharides prevent septic shock by modulating A20-and cyclooxygenase-2-mediated interleukin-10 secretion in a septic-shock mouse model.

Analysis of the signaling mechanism triggered by endotoxin-mediated toll-like receptor-4 activation using immune cell systems or rodent models may help identify potential agents for the prevention of Gram-negative bacteria infection. ß-agarase cleaves the ß-1,4-linkages of agar to produce neoagarooligosaccharides (NAOs), which have various physiological functions. The aim of this study was to investigate the efficacy of NAOs in preventing experimental sepsis caused by the administration of endotoxin or Gram-negative bacteria. Organ damage and neutrophil infiltration in an endotoxemia and septic-shock mouse model were suppressed by NAOs. Pro-inflammatory cytokine level was decreased, but IL-10 level was increased by NAO-treatment. Further induction by NAOs in the presence of endotoxin was associated with a significant induction of A20 and cyclooxygenase (COX)-2 expressions. Our data suggest that NAOs have a beneficial preventive effect in septic shock correlated with the enhancement of IL-10 via the induction of A20 and COX-2.

Phloretin Exerts Anti-Tuberculosis Activity and Suppresses Lung Inflammation.

An increase in the prevalence of the drug-resistant Mycobacteria tuberculosis necessitates developing new types of anti-tuberculosis drugs. Here, we found that phloretin, a naturally-occurring flavonoid, has anti-mycobacterial effects on H37Rv, multi-drug-, and extensively drug-resistant clinical isolates, with minimum inhibitory concentrations of 182 and 364 µM, respectively. Since Mycobacteria cause lung inflammation that contributes to tuberculosis pathogenesis, anti-inflammatory effects of phloretin in interferon-γ-stimulated MRC-5 human lung fibroblasts and lipopolysaccharide (LPS)-stimulated dendritic cells were investigated. The release of interleukin (IL)-1ß, IL-12, and tumor necrosis factor (TNF)-α was inhibited by phloretin. The mRNA levels of IL-1ß, IL-6, IL-12, TNF-α, and matrix metalloproteinase-1, as well as p38 mitogen-activated protein kinase and extracellular signal-regulated kinase phosphorylation, were suppressed. A mouse in vivo study of LPS-stimulated lung inflammation showed that phloretin effectively suppressed the levels of TNF-α, IL-1ß, and IL-6 in lung tissue with low cytotoxicity. Phloretin was found to bind M. tuberculosis ß-ketoacyl acyl carrier protein synthase III (mtKASIII) with high affinity (7.221 × 107 M-1); a binding model showed hydrogen bonding of A-ring 2'-hydroxy and B-ring 4-hydroxy groups of phloretin with Asn261 and Cys122 of mtKASIII, implying that mtKASIII can be a potential target protein. Therefore, phloretin can be a useful dietary natural product with anti-tuberculosis benefits.

Glycogen Synthase Kinase-3ß (GSK-3ß) Inhibition Enhances Dendritic Cell-based Cancer Vaccine Potency via Suppression of Interferon-γ-induced Indoleamine 2,3-Dioxygenase Expression.

Indoleamine 2,3-dioxygenase (IDO) functions as a crucial mediator of tumor-mediated immune tolerance by causing T-cell suppression via tryptophan starvation in a tumor environment. Glycogen synthase kinase-3ß (GSK-3ß) is also involved in immune and anti-tumor responses. However, the relativity of these proteins has not been as well defined. Here, we found that GSK-3ß-dependent IDO expression in the dendritic cell (DC) plays a role in anti-tumor activity via the regulation of CD8(+) T-cell polarization and cytotoxic T lymphocyte activity. By the inhibition of GSK-3ß, attenuated IDO expression and impaired JAK1/2-Stat signaling crucial for IDO expression were observed. Protein kinase Cδ (PKCδ) activity and the interaction between JAK1/2 and Stat3, which are important for IDO expression, were also reduced by GSK-3ß inhibition. CD8(+) T-cell proliferation mediated by OVA-pulsed DC was blocked by interferon (IFN)-γ-induced IDO expression via GSK-3ß activity. Specific cytotoxic T lymphocyte activity mediated by OVA-pulsed DC against OVA-expressing EG7 thymoma cells but not OVA-nonexpressing EL4 thymoma cells was also attenuated by the expressed IDO via IFN-γ-induced activation of GSK-3ß. Furthermore, tumor growth that was suppressed with OVA-pulsed DC vaccination was restored by IDO-expressing DC via IFN-γ-induced activation of GSK-3ß in an OVA-expressing murine EG7 thymoma model. Taken together, DC-based immune response mediated by interferon-γ-induced IDO expression via GSK-3ß activity not only regulates CD8(+) T-cell proliferation and cytotoxic T lymphocyte activity but also modulates OVA-pulsed DC vaccination against EG7 thymoma.

Annexin A5 increases survival in murine sepsis model by inhibiting HMGB1-mediated pro-inflammation and coagulation.

The identification of HMGB1 as a late-mediator in sepsis has highlighted HMGB1 as a promising therapeutic target for sepsis treatment. Recent studies have revealed that annexin A5, a 35 kDa Ca2+-dependent phospholipid binding protein, exerts anti-inflammatory effect by inhibiting LPS binding to TLR4/MD2 complex. Annexin A5 administration has been shown to protect against endotoxin lethality even when the treatment was given after the early cytokine response, which prompted our group to suspect that annexin A5 may inhibit the binding of HMGB1, as well as endotoxin to TLR4. Here we suggest annexin A5 as a new inhibitor of HMGB1-mediated pro-inflammatory cytokine production and coagulation in sepsis. We first confirmed the inhibitory role of annexin A5 in LPS-induced production of pro-inflammatory cytokines both in vitro and in vivo. We observed that annexin A5 protects against tissue damage and organ dysfunction during endotoxemia in vivo. We then assessed the inhibiting role of annexin A5 in HMGB1/TLR4 interaction, and showed that annexin A5 treatment reduces HMGB1-mediated cytokines IL6 and TNFα both in vitro and in vivo. Finally, we confirmed that anticoagulant property of annexin A5 persists in various septic conditions including elevated HMGB1. Overall, we suggest annexin A5 as an alternative therapeutic approach for controlling HMGB1-mediated pro-inflammation and coagulation in patients with sepsis.

Enhancement of tumor-specific T cell-mediated immunity in dendritic cell-based vaccines by Mycobacterium tuberculosis heat shock protein X.

Despite the potential for stimulation of robust antitumor immunity by dendritic cells (DCs), clinical applications of DC-based immunotherapy are limited by the low potency in generating tumor Ag-specific T cell responses. Therefore, optimal conditions for generating potent immunostimulatory DCs that overcome tolerance and suppression are key factors in DC-based tumor immunotherapy. In this study, we demonstrate that use of the Mycobacterium tuberculosis heat shock protein X (HspX) as an immunoadjuvant in DC-based tumor immunotherapy has significant potential in therapeutics. In particular, the treatment aids the induction of tumor-reactive T cell responses, especially tumor-specific CTLs. The HspX protein induces DC maturation and proinflammatory cytokine production (TNF-α, IL-1ß, IL-6, and IFN-ß) through TLR4 binding partially mediated by both the MyD88 and the TRIF signaling pathways. We employed two models of tumor progression and metastasis to evaluate HspX-stimulated DCs in vivo. The administration of HspX-stimulated DCs increased the activation of naive T cells, effectively polarizing the CD4(+) and CD8(+) T cells to secrete IFN-γ, as well as enhanced the cytotoxicity of splenocytes against HPV-16 E7 (E7)-expressing TC-1 murine tumor cells in therapeutic experimental animals. Moreover, the metastatic capacity of B16-BL6 melanoma cancer cells toward the lungs was remarkably attenuated in mice that received HspX-stimulated DCs. In conclusion, the high therapeutic response rates with tumor-targeted Th1-type T cell immunity as a result of HspX-stimulated DCs in two models suggest that HspX harnesses the exquisite immunological power and specificity of DCs for the treatment of tumors.

Antituberculosis Activity of a Naturally Occurring Flavonoid, Isorhamnetin.

Isorhamnetin (1) is a naturally occurring flavonoid having anticancer and anti-inflammatory properties. The present study demonstrated that 1 had antimycobacterial effects on Mycobacterium tuberculosis H37Rv, multi-drug- and extensively drug-resistant clinical isolates with minimum inhibitory concentrations of 158 and 316 µM, respectively. Mycobacteria mainly affect the lungs, causing an intense local inflammatory response that is critical to the pathogenesis of tuberculosis. We investigated the effects of 1 on interferon (IFN)-γ-stimulated human lung fibroblast MRC-5 cells. Isorhamnetin suppressed the release of tumor necrosis factor (TNF)-α and interleukin (IL)-12. A nontoxic dose of 1 reduced mRNA expression of TNF-α, IL-1ß, IL-6, IL-12, and matrix metalloproteinase-1 in IFN-γ-stimulated cells. Isorhamnetin inhibited IFN-γ-mediated stimulation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase and showed high-affinity binding to these kinases (binding constants: 4.46 × 10(6) M(-1) and 7.6 × 10(6) M(-1), respectively). The 4'-hydroxy group and the 3'-methoxy group of the B-ring and the 5-hydroxy group of the A-ring of 1 play key roles in these binding interactions. A mouse in vivo study of lipopolysaccharide-induced lung inflammation revealed that a nontoxic dose of 1 reduced the levels of IL-1ß, IL-6, IL-12, and INF-γ in lung tissue. These data provide the first evidence that 1 could be developed as a potent antituberculosis drug.

Critical role of TRIF and MyD88 in Mycobacterium tuberculosis Hsp70-mediated activation of dendritic cells.

As a potent immune regulator, heat shock protein 70 derived from Mycobacterium tuberculosis (Mtb Hsp70) has adjuvant effect and activates immune cells such as macrophages and dendritic cells (DCs). Although Toll-like receptors (TLRs) are known to involve in DCs activation by Mtb Hsp70, there is still a controversy and the underlying mechanism is not well understood. In this study, we examined whether TRIF and MyD88, the core adaptor molecules for TLRs signaling, regulate Mtb Hsp70-induced DCs activation. Although Mtb Hsp70 produced substantial level of cytokines (IL-6, IL-12p40, and TNF-α) in TRIF-deficient DCs in a dose-dependent manner, each level was significantly lower than that in WT cells. The cytokines production was almost abolished in MyD88-deficient DCs. Consistent with cytokine results, Mtb Hsp70-induced activation of NF-κB and MAPKs was also impaired in both TRIF- and MyD88-deficient DCs, as compared with WT cells. Inhibitor assay revealed that NF-κB, ERK, and JNK, but not p38, regulate Mtb Hsp70-induced production of cytokines. In addition, the up-regulation of co-stimulatory molecules and MHC class II was mostly TRIF-dependent in DCs in response Mtb Hsp70, whereas MyD88 was only partially involved. Finally, mixed leukocytes reaction (MLR) assay revealed that both TRIF and MyD88 are critical for DCs ability promoted by Mtb Hsp70 to differentiate naïve T cells into effector T cells of producing IFN-γ. Our findings suggest that both TRIF and MyD88 are essential for the activation and maturation of DCs in response to Mtb Hsp70.

The calmodulin inhibitor CGS 9343B inhibits voltage-dependent K+ channels in rabbit coronary arterial smooth muscle cells.

We investigated the effects of the calmodulin inhibitor CGS 9343B on voltage-dependent K(+) (Kv) channels using whole-cell patch clamp technique in freshly isolated rabbit coronary arterial smooth muscle cells. CGS 9343B inhibited Kv currents in a concentration-dependent manner, with a half-maximal inhibitory concentration (IC50) value of 0.81µM. The decay rate of Kv channel inactivation was accelerated by CGS 9343B. The rate constants of association and dissociation for CGS 9343B were 2.77±0.04µM(-1)s(-1) and 2.55±1.50s(-1), respectively. CGS 9343B did not affect the steady-state activation curve, but shifted the inactivation curve toward to a more negative potential. Train pulses (1 or 2Hz) application progressively increased the CGS 9343B-induced Kv channel inhibition. In addition, the inactivation recovery time constant was increased in the presence of CGS 9343B, suggesting that CGS 9343B-induced inhibition of Kv channel was use-dependent. Another calmodulin inhibitor, W-13, did not affect Kv currents, and did not change the inhibitory effect of CGS 9343B on Kv current. Our results demonstrated that CGS 9343B inhibited Kv currents in a state-, time-, and use-dependent manner, independent of calmodulin inhibition.

GM-CSF-loaded chitosan hydrogel as an immunoadjuvant enhances antigen-specific immune responses with reduced toxicity.

BACKGROUND: The application of vaccine adjuvants has been vigorously studied for a diverse range of diseases in order to improve immune responses and reduce toxicity. However, most adjuvants have limited uses in clinical practice due to their toxicity. METHODS: Therefore, to reduce health risks associated with the use of such adjuvants, we developed an advanced non-toxic adjuvant utilizing biodegradable chitosan hydrogel (CH-HG) containing ovalbumin (OVA) and granulocyte-macrophage colony-stimulating factor (GM-CSF) as a local antigen delivery system. RESULTS: After subcutaneous injection into mice, OVA/GM-CSF-loaded CH-HG demonstrated improved safety and enhanced OVA-specific antibody production compared to oil-based adjuvants such as Complete Freund's adjuvant (CFA) or Incomplete Freund's adjuvant (IFA). Moreover, CH-HG system-mediated immune responses was characterized by increased number of OVA-specific CD4(+) and CD8(+) INF-γ(+) T cells, leading to enhanced humoral and cellular immunity. CONCLUSIONS: In this study, the improved safety and enhanced immune response characteristics of our novel adjuvant system suggest the possibility of the extended use of adjuvants in clinical practice with reduced apprehension about toxic side effects.

The calmodulin inhibitor and antipsychotic drug trifluoperazine inhibits voltage-dependent K+ channels in rabbit coronary arterial smooth muscle cells.

We investigated the effect of the calmodulin inhibitor and antipsychotic drug trifluoperazine on voltage-dependent K(+) (Kv) channels. Kv currents were recorded by whole-cell configuration of patch clamp in freshly isolated rabbit coronary arterial smooth muscle cells. The amplitudes of Kv currents were reduced by trifluoperazine in a concentration-dependent manner, with an apparent IC50 value of 1.58±0.48 µM. The rate constants of association and dissociation by trifluoperazine were 3.73±0.33 µM(-1) s(-1) and 5.84±1.41 s(-1), respectively. Application of trifluoperazine caused a positive shift in the activation curve but had no significant effect on the inactivation curve. Furthermore, trifluoperazine provoked use-dependent inhibition of the Kv current under train pulses (1 or 2 Hz). These findings suggest that trifluoperazine interacts with Kv current in a closed state and inhibits Kv current in the open state in a time- and use-dependent manner, regardless of its function as a calmodulin inhibitor and antipsychotic drug.

Protein kinase C δ (PKCδ)-extracellular signal-regulated kinase 1/2 (ERK1/2) signaling cascade regulates glycogen synthase kinase-3 (GSK-3) inhibition-mediated interleukin-10 (IL-10) expression in lipopolysaccharide (LPS)-induced endotoxemia.

Glycogen synthase kinase-3 (GSK-3) modulates a wide array of cellular processes, including embryonic development, cell differentiation, survival, and apoptosis. Recently, it was reported that a GSK-3 inhibitor attenuates lipopolysaccharide (LPS)-induced septic shock and regulates the mortality of endotoxemic mice. However, the detailed mechanism of reduced mortality via GSK-3 inhibition is not well defined. Herein, we showed that GSK-3 inhibition induces extracellular signal-regulated kinase 1/2 (ERK1/2) activation under LPS-stressed conditions via protein kinase C δ (PKCδ) activation. Furthermore, PKCδ-induced ERK1/2 activation by the inhibition of GSK-3 provoked the production of interleukin (IL)-10, playing a crucial role in regulating endotoxemia. Using a mitogen-activated protein kinase kinase-1 (MEK-1) and PKCδ inhibitor, we confirmed that GSK-3 inhibition induces PKCδ and subsequent ERK1/2 activation, resulting in increased IL-10 expression under LPS-treated conditions. We verified that septic shock caused by LPS is attenuated by GSK-3 inhibition using a GSK-3 inhibitor. This relieved endotoxemia induced by GSK-3 inhibition was restored in an ERK1/2-dependent manner. Taken together, IL-10 expression produced by GSK-3 inhibition-induced ERK1/2 activation via PKCδ relieved LPS-mediated endotoxemia. This finding suggests that IL-10 hyperexpression resulting from GSK-3 inhibition-induced ERK activation could be a new therapeutic pathway for endotoxemia.

Resveratrol suppresses tumor progression via the regulation of indoleamine 2,3-dioxygenase.

This study showed the potential of resveratrol to inhibit the expression and activity of interferon-γ (IFN-γ)-induced indoleamine 2,3-dioxygenase (IDO) in bone marrow-derived dendritic cells (BMDCs). The mechanism of suppression was associated with the activity of Janus kinase/signal transducers and activators of transcription (JAK/STAT) and protein kinase Cδ (PKCδ). In addition, resveratrol-mediated IDO suppression in IFN-γ-stimulated BMDCs appears to play a pivotal role in anti-tumor activity through the regulation of CD8(+) T cell polarization and cytotoxic T lymphocyte (CTL) activity. Systemic administration of resveratrol suppressed tumor growth in EG7 thymoma-bearing mice in an IDO-dependent manner. Taken together, resveratrol not only regulates immune response through the regulation of IDO in a JAK/STAT1- and PKCδ-dependent manner, but also modulates the IDO-mediated immune tolerance in EG7 thymoma.

Mycobacterium tuberculosis Rv0577, a novel TLR2 agonist, induces maturation of dendritic cells and drives Th1 immune response.

Tuberculosis (TB) caused by Mycobacterium tuberculosis constitutes an ongoing threat to global health. An antigen that can induce dendritic cell (DC) maturation and lead to enhanced cellular immunity is crucial to the development of an effective TB vaccine. Here, we investigated the functional roles and the related signaling mechanism of the Rv0577 protein, a M. tuberculosis complex-restricted secreted protein involved in the methylglyoxal detoxification pathway. Rv0577 recognizes Toll-like receptor 2 (TLR2) and functionally induces DC maturation by augmenting the expression of cell surface molecules (CD80, CD86, and MHC class I and II) and proinflammatory cytokine production (TNF-α, IL-1ß, IL-6, and IL-12p70) in DCs on MyD88-dependent signaling, mitogen-activated protein kinases, and nuclear factor κB signaling pathways. In addition, Rv0577-treated DCs activated naive T cells, effectively polarized CD4(+) and CD8(+) T cells to secrete IFN-γ and IL-2, and induced T-cell proliferation, indicating that this protein possibly contributes to Th1-polarization of the immune response. More important, unlike LPS, Rv0577-treated DCs specifically induced the proliferation of memory CD4(+)/CD8(+)CD44(high)CD62L(low) T cells in the spleen of M. tuberculosis-infected mice in a TLR2-dependent manner. Taken together, these findings suggest that Rv0577 may regulate innate and adaptive immunity by interacting with TLR2, a finding that could be helpful in the design of new TB vaccines.

Effect of 1-methyl-D-tryptophan and adoptive transfer of dendritic cells on polymicrobial sepsis induced by cecal content injection.

A mouse model of polymicrobial sepsis induced by cecal content injection (CCI) was developed with the aim of gaining a better understanding of the mechanism of sepsis. This model has a similar survival pattern to the conventional model with the added benefits of ability to vary the severity of sepsis and greater consistency. Administration of 1-methyl-D-tryptophan (1-MT) to inhibit indoleamine 2,3-dioxygenase (IDO) in mice with CCI-induced sepsis increased the survival rate and tended to up-regulate IL-10/IL-12 serum concentrations. The effectiveness of 1-MT was confirmed by increases in IL-10 over IL-12 in bone marrow-derived dendritic cells (BMDCs) treated with LPS and 1-MT and a superior survival rate 24 hr after injection of these double treated BMDCs in the CCI-induced sepsis model. Therefore, CCI is both a useful and reliable technique for investigating polymicrobial sepsis. The present findings using this newly developed model suggest that inhibition of IDO alleviates the severity of polymicrobial sepsis and modulates the immune response even in cases of severe systemic septic inflammation.

Biomimetically Engineered Amyloid-Shelled Gold Nanocomplexes for Discovering α-Synuclein Oligomer-Degrading Drugs.

The assembly of α-synuclein (αS) oligomers is recognized as the main pathological driver of synucleinopathies. While the elimination of toxic αS oligomers shows promise for the treatment of Parkinson's disease (PD), the discovery of αS oligomer degradation drugs has been hindered by the lack of proper drug screening tools. Here, we report a drug screening platform for monitoring the efficacy of αS-oligomer-degrading drugs using amyloid-shelled gold nanocomplexes (ASGNs). We fabricate ASGNs in the presence of dopamine, mimicking the in vivo generation process of pathological αS oligomers. To test our platform, the first of its kind for PD drugs, we use αS-degrading proteases and various small molecular substances that have shown efficacy in PD treatment. We demonstrate that the ASGN-based in vitro platform has strong potential to discover effective αS-oligomer-targeting drugs, and thus it may reduce the attrition problem in drug discovery for PD treatment.