Mie Magnetic Structural Colors from Short Chains of TiO2 Nanospheres.

We demonstrate distinctive structural colors within a small footprint by using a short chain of nanospheres. Rather than using high-index materials like Si (n ∼ 4), which ensure strong modal confinement, TiO2 is employed. TiO2 has an intermediate index (n ∼ 2), promoting stronger modal coupling between the magnetic dipoles of each particle. This approach enables selective engineering of the magnetic response and yields larger spectral changes compared to that of Si. Despite the lower refractive index, the absence of absorption in TiO2 also produces higher scattering intensities than Si. We develop a quasistatic analytical model that describes the dipolar modal coupling in a trimer and use it to reveal distinct magnetic field strengths in the outer or central particle depending on the polarization of incident light. These results suggest pathways to manipulate the magnetic field in chains of particles and create vibrant structural colors with simple configurations.

Cycloolivil Isolated from Nardostachys jatamansi Inhibits TNF-α/IFN-γ-Induced Chemokine Production by Blocking NF-κB and JAK/STAT Activation in HaCaT Keratinocytes.

Nardostachys jatamansi is widely used as a traditional medicine in Asian countries. Numerous recent studies have reported the biological activities of its secondary metabolites and extracts. In this study, a total of 14 components were isolated, including cycloolivil and 2-(3'-hydroxy-5'-ethoxyphenyl)-3-hydroxylmethyl-7-methoxy-2,3-dihydrobenzofuran-5-carboxylic acid, which were first discovered in N. jatamansi. The isolated compounds were investigated for their anti-inflammatory effects on HaCaT keratinocytes and their potential to alleviate skin inflammation. The results of the screening revealed that cycloolivil and 4ß-hydroxy-8ß-methoxy-10-methylene-2,9-dioxatricyclo[4.3.1.03,7]decane reduced the production of inflammatory cytokines induced by TNF-α/IFN-γ, such as IL-6, IL-8, and RANTES, in keratinocytes. This study focused on exploring the biological effects of cycloolivil, and the results suggested that cycloolivil inhibits the expression of COX-2 proteins. Further mechanistic evaluations confirmed that the anti-inflammatory effects of cycloolivil were mediated by blockage of the NF-κB and JAK/STAT signaling pathways. These results suggest that cycloolivil isolated from N. jatamansi could be used to treat skin inflammatory diseases.

Synthesis and Evaluation of Chloride-Substituted Ramalin Derivatives for Alzheimer's Disease Treatment.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by the accumulation of amyloid-beta plaques and hyperphosphorylated tau proteins, leading to cognitive decline and neuronal death. However, despite extensive research, there are still no effective treatments for this condition. In this study, a series of chloride-substituted Ramalin derivatives is synthesized to optimize their antioxidant, anti-inflammatory, and their potential to target key pathological features of Alzheimer's disease. The effect of the chloride position on these properties is investigated, specifically examining the potential of these derivatives to inhibit tau aggregation and beta-site amyloid precursor protein cleaving enzyme 1 (BACE-1) activity. Our findings demonstrate that several derivatives, particularly RA-3Cl, RA-4Cl, RA-26Cl, RA-34Cl, and RA-35Cl, significantly inhibit tau aggregation with inhibition rates of approximately 50%. For BACE-1 inhibition, Ramalin and RA-4Cl also significantly decrease BACE-1 expression in N2a cells by 40% and 38%, respectively, while RA-23Cl and RA-24Cl showed inhibition rates of 30% and 35% in SH-SY5Y cells. These results suggest that chloride-substituted Ramalin derivatives possess promising multifunctional properties for AD treatment, warranting further investigation and optimization for clinical applications.

Shaping Copper Oxide Layers on Gold Nanoparticle Ensembles by Controlled Electrodeposition with Single Particle Scatterometry.

Electrodeposition of copper on gold nanoelectrode ensembles result in the formation of uniform copper oxide layers on individual nanoparticles. A linear sweep of voltammetric change induces three distinct morphologies dependent upon particle density. Ex situ imaging and in situ scatterometry at a single-particle level identifies multi-step electrochemical growth sequences that deviated from classical nucleation and growth pathways. In addition, the study demonstrated the possibility of synthesizing sophisticated structures based on the symmetry of nanoelectrodes. This result guides the nanoscale morphology control of electrode ensembles with potential application in electrocatalysis and sensing.

Anti-Neuroinflammatory and Neuroprotective Effect of Intermedin B Isolated from the Curcuma longa L. via NF-κB and ROS Inhibition in BV2 Microglia and HT22 Hippocampal Cells.

Compounds derived from Curcuma longa L. (C. longa) have been extensively studied and reported to be effective and safe for the prevention and treatment of various diseases, but most research has been focused on curcuminoids derived from C. longa. As neurodegenerative diseases are associated with oxidation and inflammation, the present study aimed to isolate and identify active compounds other than curcuminoids from C. longa to develop substances to treat these diseases. Seventeen known compounds, including curcuminoids, were chromatographically isolated from the methanol extracts of C. longa, and their chemical structures were identified using 1D and 2D NMR spectroscopy. Among the isolated compounds, intermedin B exhibited the best antioxidant effect in the hippocampus and anti-inflammatory effect in microglia. Furthermore, intermedin B was confirmed to inhibit the nuclear translocation of NF-κB p-65 and IκBα, exerting anti-inflammatory effects and inhibiting the generation of reactive oxygen species, exerting neuroprotective effects. These results highlight the research value of active components other than curcuminoids in C. longa-derived compounds and suggest that intermedin B may be a promising candidate for the prevention of neurodegenerative diseases.

Synthetic Glabridin Derivatives Inhibit LPS-Induced Inflammation via MAPKs and NF-κB Pathways in RAW264.7 Macrophages.

Glabridin is a polyphenolic compound with reported anti-inflammatory and anti-oxidative effects. In the previous study, we synthesized glabridin derivatives-HSG4112, (S)-HSG4112, and HGR4113-based on the structure-activity relationship study of glabridin to improve its biological efficacy and chemical stability. In the present study, we investigated the anti-inflammatory effects of the glabridin derivatives in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We found that the synthetic glabridin derivatives significantly and dose-dependently suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2), and decreased the level of inducible nitric oxygen synthase (iNOS) and cyclooxygenase-2 (COX-2) and the expression of pro-inflammatory cytokines interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor alpha (TNF-α). The synthetic glabridin derivatives inhibited the nuclear translocation of the NF-κB by inhibiting phosphorylation of the inhibitor of κB alpha (IκB-α), and distinctively inhibited the phosphorylation of ERK, JNK, and p38 MAPKs. In addition, the compounds increased the expression of antioxidant protein heme oxygenase (HO-1) by inducing nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) through ERK and p38 MAPKs. Taken together, these results indicate that the synthetic glabridin derivatives exert strong anti-inflammatory effects in LPS-stimulated macrophages through MAPKs and NF-κB pathways, and support their development as potential therapeutics against inflammatory diseases.

Macluraxanthone B inhibits LPS-induced inflammatory responses in RAW264.7 and BV2 cells by regulating the NF-κB and MAPK signaling pathways.

OBJECTIVE: The prenylated xanthones compounds, macluraxanthone B (MCXB) was isolated from the MeOH extracts of Cudrania tricuspidata. In this study, we investigated the effect of MCXB on inflammatory response. MATERIALS AND METHODS: Anti-inflammatory effects of MCXB were examined in lipopolysaccharide (LPS)-stimulated RAW264.7 and BV2 cells. We observed their anti-inflammatory effects by ELISA, western blot analysis, and immunofluorescence. RESULTS: MCXB significantly inhibited the LPS-stimulated production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-6 (IL-6), and tumor necrosis factor (TNF)-α in RAW264.7 and BV2 cells. MCXB also reduced the LPS-induced expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 proteins. Incubating cells with MCXB prevented subsequent activation of the nuclear factor kappa B (NF-κB) signaling pathway by inhibiting the nuclear localization and DNA-binding activity of the p65 subunit induced by LPS. MCXB inhibited the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 mitogen-activated protein kinases (MAPKs) in RAW264.7 and BV2 cells. MCXB induced the expression of heme oxygenase (HO)-1 protein, and the inhibitory effect of MCXB on nitric oxide production was partially reversed by a selective HO-1 inhibitor. DISCUSSION AND CONCLUSIONS: Our results suggested that the anti-inflammatory effect of MCXB is partly regulated by HO-1 induction. In conclusion, MCXB could be a useful candidate for the development of therapeutic and preventive agents to treat inflammatory diseases.

Anti-Inflammatory Effects Exerted by 14-Methoxyalternate C from Antarctic Fungal Strain Pleosporales sp. SF-7343 via the Regulation of NF-κB and JAK2/STAT3 in HaCaT Human Keratinocytes.

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a profound negative impact on patients' quality of life. Four known secondary fungal metabolites were found in the chemical study of the Antarctic fungus Pleosporales sp. SF-7343, including 14-methoxyalternate C (1), 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (2), 3,8,10-trihydroxy-4-methoxy-6-methylbenzocoumarin (3), and alternariol monomethyl ether (4). Additionally, we identified the skin anti-inflammatory composition from the SF-7343 strain. Interleukin-8 and -6 Screening results showed that compound 1 inhibited IL-8 and IL-6 in tumor necrosis factor-α/interferon-γ stimulated HaCaT cells. Compound 1 showed inhibitory effects on MDC and RANTES. It also downregulated the expression of intercellular adhesion molecule-1 (ICAM-1) and upregulated the expression of involucrin. The results of the mechanistic study showed that compound 1 inhibited the nuclear translocation of nuclear factor-kappa B p65 and STAT3. In conclusion, this study demonstrates the potential of the Antarctic fungal strain SF-7343 as a bioactive resource to inhibit skin inflammation, such as AD.

Identification of Potential Anti-Neuroinflammatory Inhibitors from Antarctic Fungal Strain Aspergillus sp. SF-7402 via Regulating the NF-κB Signaling Pathway in Microglia.

Microglia play a significant role in immune defense and tissue repair in the central nervous system (CNS). Microglial activation and the resulting neuroinflammation play a key role in the pathogenesis of neurodegenerative disorders. Recently, inflammation reduction strategies in neurodegenerative diseases have attracted increasing attention. Herein, we discovered and evaluated the anti-neuroinflammatory potential of compounds from the Antarctic fungi strain Aspergillus sp. SF-7402 in lipopolysaccharide (LPS)-stimulated BV2 cells. Four metabolites were isolated from the fungi through chemical investigations, namely, 5-methoxysterigmatocystin (1), sterigmatocystin (2), aversin (3), and 6,8-O-dimethylversicolorin A (4). Their chemical structures were elucidated by extensive spectroscopic analysis and HR-ESI-MS, as well as by comparison with those reported in literature. Anti-neuroinflammatory effects of the isolated metabolites were evaluated by measuring the production of nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in LPS-activated microglia at non-cytotoxic concentrations. Sterigmatocystins (1 and 2) displayed significant effects on NO production and mild effects on TNF-α and IL-6 expression inhibition. The molecular mechanisms underlying this activity were investigated using Western blot analysis. Sterigmatocystin treatment inhibited NO production via downregulation of inducible nitric oxide synthase (iNOS) expression in LPS-stimulated BV2 cells. Additionally, sterigmatocystins reduced nuclear translocation of NF-κB. These results suggest that sterigmatocystins present in the fungal strain Aspergillus sp. are promising candidates for the treatment of neuroinflammatory diseases.

Anti-inflammatory spiroditerpenoids from Penicillium bialowiezense.

Inflammation is a vital process that maintains tissue homeostasis. However, it is widely known that uncontrolled inflammation can contribute to the development of various diseases. This study aimed to discover anti-inflammatory metabolites from Penicillium bialowiezense. Seven spiroditerpenoids, including two new compounds, breviones P and Q (1 and 2), were isolated and characterized by various spectroscopic and spectrometric methods. All isolated compounds were initially tested for their inhibitory effects against lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 macrophages. Of these, brevione A (3) exhibited this activity with a half-maximal inhibitory concentration value of 9.5 µM. Further mechanistic studies demonstrated that 3 could suppress the expression of pro-inflammatory cytokines and mediators, such as NO, prostaglandin E2, interleukin (IL)-1ß, tumor necrosis factor-α, IL-6, and IL-12 by inhibiting the activation of nuclear factor-kappa B and c-Jun N-terminal kinase.

Anti-inflammatory Effects of Sanhuang-Siwu-Tang in Lipopolysaccharide-Stimulated RAW264.7 Macrophages and BV2 Microglial Cells.

Sanhuang-Siwu-Tang (SST), composed of seven medicinal herbs, is a well-known herbal formula used for the treatment of gynecologic diseases. To expand the clinical use of SST, we explored the anti-inflammatory or anti-neuroinflammatory effects of SST water extract in lipopolysaccharide-stimulated RAW264.7 macrophages and BV2 microglial cells. According to HPLC analysis, the main components of SST were from Scutellariae Radix, Coptidis Rhizoma, and Paeoniae Radix. SST significantly inhibited pro-inflammatory mediators including lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E2 (PGE2) as well as protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and the production of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in LPS-stimulated RAW264.7 macrophages and BV2 microglial cells. Furthermore, these anti-inflammatory or anti-neuroinflammatory effects of SST were mediated by mitogen-activated protein kinase-related proteins (MAPK) and nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB)-related proteins. Overall, this study demonstrated that SST is a potential therapeutic formula for the prevention or treatment of inappropriate inflammation, neuroinflammation, or neurodegenerative diseases.

Anti-Inflammatory Effects of Compounds from Cudrania tricuspidata in HaCaT Human Keratinocytes.

The root bark of Cudrania tricuspidata has been reported to have anti-sclerotic, anti-inflammatory, antioxidant, neuroprotective, hepatoprotective, and cytotoxic activities. In the present study, the effect of 16 compounds from C. tricuspidata on tumor necrosis factor-α+interferon-γ-treated HaCaT cells were investigated. Among these 16 compounds, 11 decreased IL-6 production and 15 decreased IL-8 production. The six most effective compounds, namely, steppogenin (2), cudraflavone C (6), macluraxanthone B (12), 1,6,7-trihydroxy-2-(1,1-dimethyl-2-propenyl)-3- methoxyxanthone (13), cudraflavanone B (4), and cudratricusxanthone L (14), were selected for further experiments. These six compounds decreased the expression levels of chemokines, such as regulated on activation, normal T cell expressed and secreted (RANTES) and thymus and activation-regulated chemokine (TARC), and downregulated the protein expression levels of intercellular adhesion molecule-1. Compounds 2, 6, 12, 4, and 14 inhibited nuclear factor-kappa B p65 translocation to the nucleus; however, compound 13 showed no significant effects. In addition, extracellular signal regulatory kinase-1/2 phosphorylation was only inhibited by compound 14, whereas p38 phosphorylation was inhibited by compounds 13 and 4. Taken together, the compounds from C. tricuspidata showed potential to be further developed as therapeutic agents to suppress inflammation in skin cells.

Anti-Inflammatory Effects of Metabolites from Antarctic Fungal Strain Pleosporales sp. SF-7343 in HaCaT Human Keratinocytes.

Chemical investigation of the Antarctic fungi Pleosporales sp. SF-7343 revealed four known secondary fungal metabolites: alternate C (1), altenusin (2), alternariol (3), and altenuene (4). The compound structures were identified primarily by NMR and MS analyses. Atopic dermatitis, an inflammatory disease, is driven by the abnormal activation of T helper (Th) 2 cells and barrier dysfunction. We attempted to identify the anti-inflammatory components of SF-7343. Initial screening showed that compounds 1 and 3 inhibited the secretion of interleukin-8 and -6 in tumor necrosis factor-α/interferon-γ-treated HaCaT cells, and these compounds also showed inhibitory effects on CCL5 and CCL22. Compounds 1 and 3 also downregulated the protein expression levels of intercellular adhesion molecule-1 and upregulated the expression of filaggrin and involcurin. The mechanism study results showed that compounds 1 and 3 inhibited nuclear translocation of nuclear factor-kappa B p65 and the phosphorylation of STAT1 and STAT3. Compound 1, but not compound 3, significantly promoted the expression of heme oxygenase (HO)-1. The effects of compound 1 were partly reversed by co-treatment with a HO-1 inhibitor, tin protoporphyrin IX. Taken together, this study demonstrates the potential value of Antarctic fungal strain SF-7343 isolates as a bioresource for bioactive compounds to prevent skin inflammation.

Betulinic Acid Ameliorates the Severity of Acute Pancreatitis via Inhibition of the NF-κB Signaling Pathway in Mice.

Acute pancreatitis (AP) is an inflammatory disorder, involving acinar cell death and the release of inflammatory cytokines. Currently, there are limited effective therapeutic agents for AP. Betulinic acid (BA) is a pentacyclic triterpenoid extracted from Betula platyphylla that has been shown to have anti-inflammatory effects. In this study, we aimed to investigate the effects of BA on AP and elucidate the potential underlying mechanisms. AP was induced in mice through six intraperitoneal injections of cerulein. After the last cerulein injection, the mice were sacrificed. Our results revealed that pre- and post-treatment with BA significantly reduced the severity of pancreatitis, as evidenced by a decrease in histological damage in the pancreas and lung, serum amylase and lipase activity and pancreatic myeloperoxidase activity. Furthermore, BA pretreatment reduced proinflammatory cytokine production, augmentation of chemokines, and infiltration of macrophages and neutrophils in the pancreas of AP mice. In addition, mice that were pretreated with BA showed a reduction in Iκ-Bα degradation and nuclear factor-kappa B (NF-κB) binding activity in the pancreas. Moreover, BA reduced the production of proinflammatory cytokines and NF-κB activation in pancreatic acinar cells (PACs). These findings suggest that BA may have prophylactic and therapeutic effects on AP via inhibition of the NF-κB signaling pathway.

Potential of Ramalin and Its Derivatives for the Treatment of Alzheimer's Disease.

The pathogenesis of Alzheimer's disease (AD) is still unclear, and presently there is no cure for the disease that can be used for its treatment or to stop its progression. Here, we investigated the therapeutic potential of ramalin (isolated from the Antarctic lichen, Ramalina terebrata), which exhibits various physiological activities, in AD. Specifically, derivatives were synthesized based on the structure of ramalin, which has a strong antioxidant effect, BACE-1 inhibition activity, and anti-inflammatory effects. Therefore, ramalin and its derivatives exhibit activity against multiple targets associated with AD and can serve as potential therapeutic agents for the disease.

PTP1B Inhibitory Secondary Metabolites from an Antarctic Fungal Strain Acremonium sp. SF-7394.

Chemical investigation of the Antarctic lichen-derived fungal strain Acremonium sp. SF-7394 yielded a new amphilectane-type diterpene, acrepseudoterin (1), and a new acorane-type sesquiterpene glycoside, isocordycepoloside A (2). In addition, three known fungal metabolites, (-)-ternatin (3), [D-Leu]-ternatin (4), and pseurotin A (5), were isolated from the EtOAc extract of the fungal strain. Their structures were mainly elucidated by analyzing their NMR and MS data. The absolute configuration of 1 was proposed by electronic circular dichroism calculations, and the absolute configuration of the sugar unit in 2 was determined by a chemical method. The inhibitory effects of the isolated compounds on protein tyrosine phosphatase 1B (PTP1B) were evaluated by enzymatic assays; results indicated that acrepseudoterin (1) and [D-Leu]-ternatin (4) dose-dependently inhibited the enzyme activity with IC50 values of 22.8 ± 1.1 µM and 14.8 ± 0.3 µM, respectively. Moreover, compound 1 was identified as a competitive inhibitor of PTP1B.

Terrein suppressed lipopolysaccharide-induced neuroinflammation through inhibition of NF-κB pathway by activating Nrf2/HO-1 signaling in BV2 and primary microglial cells.

In the course of our continuous investigation on the bioactive marine-derived fungal metabolites, terrein was isolated from marine-derived fungal strain Penicillium sp. SF-7181. Terrein inhibited the overproduction of pro-inflammatory mediators, such as nitric oxide (NO) and prostaglandin E2 (PGE2), as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated BV2 and primary microglial cells. This compound also repressed the LPS-induced production of pro-inflammatory cytokines, interleukin (IL)-1ß and IL-6. These inhibitory effects of terrein were associated with the inactivation of the nuclear factor kappa B (NF-κB) pathway through suppression of the translocation of p65/p50 heterodimer into the nucleus, the phosphorylation and degradation of inhibitor kappa B (IκB)-α and the DNA binding activity of the p65 subunit. In addition, terrein induced the protein expression of heme oxygenase (HO)-1 through the activation of nuclear transcription factor erythroid-2 related factor 2 (Nrf2) in BV2 and primary microglial cells. The anti-inflammatory effect of terrein was blocked by pre-treatment with a selective HO-1 inhibitor, suggesting that its anti-neuroinflammatory effect is mediated by HO-1 induction.

Anti-inflammatory Metabolites from Chaetomium nigricolor.

Twelve metabolites were obtained from the culture media of Chaetomium nigricolor, including a new furan derivative, methyl succinyl Sumiki's acid (1), and two new atropisomers of the previously reported bis-naphtho-γ-pyrones, (aS)-asperpyrone A and (aS)-fonsecinone A (2 and 3). The structures were elucidated by spectroscopic, chemical, and chiroptical techniques. Compounds 2 and 3 inhibited nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophages. Compound 2 was found to inhibit nuclear factor-kappa B and c-Jun N-terminal kinase activation, in turn suppressing pro-inflammatory mediators and cytokines including nitric oxide, prostaglandin E2, interleukin (IL)-1ß, tumor necrosis factor-α, IL-6, and IL-12.

Anti-Inflammatory and Protein Tyrosine Phosphatase 1B Inhibitory Metabolites from the Antarctic Marine-Derived Fungal Strain Penicillium glabrum SF-7123.

A chemical investigation of the marine-derived fungal strain Penicillium glabrum (SF-7123) revealed a new citromycetin (polyketide) derivative (1) and four known secondary fungal metabolites, i.e, neuchromenin (2), asterric acid (3), myxotrichin C (4), and deoxyfunicone (5). The structures of these metabolites were identified primarily by extensive analysis of their spectroscopic data, including NMR and MS data. Results from the initial screening of anti-inflammatory effects showed that 2, 4, and 5 possessed inhibitory activity against the excessive production of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated BV2 microglial cells, with IC50 values of 2.7 µM, 28.1 µM, and 10.6 µM, respectively. Compounds 2, 4, and 5 also inhibited the excessive production of NO, with IC50 values of 4.7 µM, 41.5 µM, and 40.1 µM, respectively, in LPS-stimulated RAW264.7 macrophage cells. In addition, these compounds inhibited LPS-induced overproduction of prostaglandin E2 in both cellular models. Further investigation of the most active compound (2) revealed that these anti-inflammatory effects were associated with a suppressive effect on the over-expression of inducible nitric oxide synthase and cyclooxygenase-2. Finally, we showed that the anti-inflammatory effects of compound 2 were mediated via the downregulation of inflammation-related pathways such as those dependent on nuclear factor kappa B and p38 mitogen-activated protein kinase in LPS-stimulated BV2 and RAW264.7 cells. In the evaluation of the inhibitory effects of the isolated compounds on protein tyrosine phosphate 1B (PTP1B) activity, compound 4 was identified as a noncompetitive inhibitor of PTP1B, with an IC50 value of 19.2 µM, and compound 5 was shown to inhibit the activity of PTP1B, with an IC50 value of 24.3 µM, by binding to the active site of the enzyme. Taken together, this study demonstrates the potential value of marine-derived fungal isolates as a bioresource for bioactive compounds.

Neuroprotective and Anti-Inflammatory Effects of Kuwanon C from Cudrania tricuspidata Are Mediated by Heme Oxygenase-1 in HT22 Hippocampal Cells, RAW264.7 Macrophage, and BV2 Microglia.

Heme oxygenase (HO)-1 is a detoxifying phase II enzyme that plays a role in both inflammatory and oxidative stress responses. Curdrania tricuspidata is widespread throughout East Asia and is used as a therapeutic agent in traditional medicine. We investigated whether treatment with sixteen flavonoid or xanthone compounds from C. tricuspidata could induce HO-1 expression in HT22 hippocampal cells, RAW264.7 macrophage, and BV2 microglia. In these compounds, kuwanon C showed the most remarkable HO-1 expression effects. In addition, treatment with kuwanon C reduced cytoplasmic nuclear erythroid 2-related factor (Nrf2) expression and increased Nrf2 expression in the nucleus. Significant inhibition of glutamate-induced oxidative injury and induction of reactive oxygen species (ROS) occurred when HT22 hippocampal cells were pretreated with kuwanon C. The levels of inflammatory mediator and cytokine, which increased following lipopolysaccharide (LPS) stimulation, were suppressed in RAW264.7 macrophage and BV2 microglia after kuwanon C pretreatment. Kuwanon C also attenuated p65 DNA binding and translocation into the nucleus in LPS-induced RAW264.7 and BV2 cells. The anti-inflammatory, anti-neuroinflammatory, and neuroprotective effects of kuwanon C were reversed when co-treatment with HO-1 inhibitor of tin protoporphyrin-IX (SnPP). These results suggest that the neuroprotective and anti-inflammatory effects of kuwanon C are regulated by HO-1 expression.