Experimental and Theoretical Mutation of Exciton States on the Smallest Type-I Photosynthetic Reaction Center Complex of a Green Sulfur Bacterium Chlorobaclum tepidum.

The exciton states on the smallest type-I photosynthetic reaction center complex of a green sulfur bacterium Chlorobaculum tepidum (GsbRC) consisting of 26 bacteriochlorophylls a (BChl a) and four chlorophylls a (Chl a) located on the homodimer of two PscA reaction center polypeptides were investigated. This analysis involved the study of exciton states through a combination of theoretical modeling and the genetic removal of BChl a pigments at eight sites. (1) A theoretical model of the pigment assembly exciton state on GsbRC was constructed using Poisson TrESP (P-TrESP) and charge density coupling (CDC) methods based on structural information. The model reproduced the experimentally obtained absorption spectrum, circular dichroism spectrum, and excitation transfer dynamics, as well as explained the effects of mutation. (2) Eight BChl a molecules at different locations on the GsbRC were selectively removed by genetic exchange of the His residue, which ligates the central Mg atom of BChl a, with the Leu residue on either one or two PscAs in the RC. His locations are conserved among all type-I RC plant polypeptide, cyanobacteria, and bacteria amino acid sequences. (3) Purified mutant-GsbRCs demonstrated distinct absorption and fluorescence spectra at 77 K, which were different from each other, suggesting successful pigment removal. (4) The same mutations were applied to the constructed theoretical model to analyze the outcomes of these mutations. (5) The combination of theoretical predictions and experimental mutations based on structural information is a new tool for studying the function and evolution of photosynthetic reaction centers.

Extracellular aaRSs drive autoimmune and inflammatory responses in rheumatoid arthritis via the release of cytokines and PAD4.

OBJECTIVES: Recent studies demonstrate that extracellular-released aminoacyl-tRNA synthetases (aaRSs) play unique roles in immune responses and diseases. This study aimed to understand the role of extracellular aaRSs in the pathogenesis of rheumatoid arthritis (RA). METHODS: Primary macrophages and fibroblast-like synoviocytes were cultured with aaRSs. aaRS-induced cytokine production including IL-6 and TNF-α was detected by ELISA. Transcriptomic features of aaRS-stimulated macrophages were examined using RNA-sequencing. Serum and synovial fluid (SF) aaRS levels in patients with RA were assessed using ELISA. Peptidyl arginine deiminase (PAD) 4 release from macrophages stimulated with aaRSs was detected by ELISA. Citrullination of aaRSs by themselves was examined by immunoprecipitation and western blotting. Furthermore, aaRS inhibitory peptides were used for inhibition of arthritis in two mouse RA models, collagen-induced arthritis and collagen antibody-induced arthritis. RESULTS: All 20 aaRSs functioned as alarmin; they induced pro-inflammatory cytokines through the CD14-MD2-TLR4 axis. Stimulation of macrophages with aaRSs displayed persistent innate inflammatory responses. Serum and SF levels of many aaRSs increased in patients with RA compared with control subjects. Furthermore, aaRSs released PAD4 from living macrophages, leading to their citrullination. We demonstrate that aaRS inhibitory peptides suppress cytokine production and PAD4 release by aaRSs and alleviate arthritic symptoms in a mouse RA model. CONCLUSIONS: Our findings uncovered the significant role of aaRSs as a novel alarmin in RA pathogenesis, indicating that their blocking agents are potent antirheumatic drugs.

Fatigue on Waking, Insomnia, and Workplace Relationship Problems May Help to Detect Suicidal Ideation among New Middle-Aged Primary Care Patients: A 6-Month Prospective Study in Japan.

Signs of suicidal depression often go undetected in primary care settings. This study explored predictive factors for depression with suicidal ideation (DSI) among middle-aged primary care patients at 6 months after an initial clinic visit. New patients aged 35-64 years were recruited from internal medicine clinics in Japan. Baseline characteristics were elicited using self-administered and physician questionnaires. DSI was evaluated using the Zung Self-Rating Depression Scale and the Profile of Mood States at enrollment and 6 months later. Multiple logistic regression analysis was conducted to calculate adjusted odds ratios for DSI. Sensitivity, specificity, and likelihood ratios for associated factors were calculated. Among 387 patients, 13 (3.4%) were assessed as having DSI at 6 months. Adjusted for sex, age, and related factors, significant odds ratios for DSI were observed for "fatigue on waking ≥1/month" (7.90, 95% confidence intervals: 1.06-58.7), "fatigue on waking ≥1/week" (6.79, 1.02-45.1), "poor sleep status" (8.19, 1.05-63.8), and "relationship problems in the workplace" (4.24, 1.00-17.9). Fatigue on waking, sleep status, and workplace relationship problems may help predict DSI in primary care. Because the sample size in this investigation was small, further studies with larger samples are needed to confirm our findings.

Hypoxia-inducible factor 1α inhibitor induces cell death via suppression of BCR-ABL1 and Met expression in BCR-ABL1 tyrosine kinase inhibitor sensitive and resistant chronic myeloid leukemia cells.

Chronic myeloid leukemia (CML) has a markedly improved prognosis with the use of breakpoint cluster region-abelson 1 (BCR-ABL1) tyrosine kinase inhibitors (BCR-ABL1 TKIs). However, approximately 40% of patients are resistant or intolerant to BCR-ABL1 TKIs. Hypoxia-inducible factor 1α (HIF-1α) is a hypoxia response factor that has been reported to be highly expressed in CML patients, making it a therapeutic target for BCR-ABL1 TKI-sensitive CML and BCR-ABL1 TKI-resistant CML. In this study, we examined whether HIF-1α inhibitors induce cell death in CML cells and BCR-ABL1 TKI-resistant CML cells. We found that echinomycin and PX-478 induced cell death in BCR-ABL1 TKIs sensitive and resistant CML cells at similar concentrations while the cell sensitivity was not affected with imatinib or dasatinib in BCR-ABL1 TKIs resistant CML cells. In addition, echinomycin and PX-478 inhibited the c-Jun N-terminal kinase (JNK), Akt, and extracellular-regulated protein kinase 1/2 (ERK1/2) activation via suppression of BCR-ABL1 and Met expression in BCR-ABL1 sensitive and resistant CML cells. Moreover, treatment with HIF-1α siRNA induced cell death by inhibiting BCR-ABL1 and Met expression and activation of JNK, Akt, and ERK1/2 in BCR-ABL1 TKIs sensitive and resistant CML cells. These results indicated that HIF-1α regulates BCR-ABL and Met expression and is involved in cell survival in CML cells, suggesting that HIF-1α inhibitors induce cell death in BCR-ABL1 TKIs sensitive and resistant CML cells and therefore HIF-1α inhibitors are potential candidates for CML treatment. [BMB Reports 2023; 56(2): 78-83].

Polarizable Molecular Block Model: Toward the Development of an Induced Dipole Force Field for DNA.

For flexible and highly ionized macromolecules such as DNA, it is important to correctly evaluate the intramolecular polarization in an induced dipole force field. In a proposed polarizable molecular block (PMB) model, a large molecule is divided into several molecular blocks. The atomic charges of the blocks are optimized by using the respective electrostatic potentials (ESPs) on the molecular surface. By using the capped hydrogen removal operation, the total charge of the blocks is controlled exactly to have an integer charge. The atomic polarizabilities of the blocks are optimized by using the respective polarized one-electron potentials that are the differences between ESPs with and without an external test charge. Induced dipole-charge interactions between the blocks are all included, but those interactions within the blocks are strictly excluded. All dipole-dipole interactions are included, but the damping functions are applied to the close dipole-dipole pairs. Several types of damping (simple scaling, exponential, linear, and Gaussian) are evaluated. The validity of the PMB model was verified by using trinucleotide duplexes which have A-, B-, and Z-DNA forms. The reference energies of trinucleotide duplexes including counterions (GGT3Na-ACC3Na, GAC3Na-GTC3Na, and GCG3Na-CGC3Na) are calculated using ωB97XD/aug-cc-pVDZ. All damping types reproduced well the reference interaction energies, dipole moments, and ESPs. Among them, the simple scaling with strong attenuation to 1-2 atomic pairs showed the highest stability against the polarization catastrophe. This study shows that it is possible to develop a high-quality polarizable force field by treating the intramolecular polarization on a block-by-block basis.

Dimethyl Fumarate Induces Apoptosis via Inhibition of NF-κB and Enhances the Effect of Paclitaxel and Adriamycin in Human TNBC Cells.

Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.

Antioxidative enzyme NAD(P)H quinone oxidoreductase 1 (NQO1) modulates the differentiation of Th17 cells by regulating ROS levels.

NAD(P)H quinone oxidoreductase 1 (NQO1) is a flavoprotein that catalyzes two-electron reduction of quinone to hydroquinone by using nicotinamide adenine dinucleotide (NADPH), and functions as a scavenger for reactive oxygen species (ROS). The function of NQO1 in the immune response is not well known. In the present study, we demonstrated that Nqo1-deficient T cells exhibited reduced induction of T helper 17 cells (Th17) in vitro during Th17(23)- and Th17(ß)- skewing conditions. Nqo1-deficient mice showed ameliorated symptoms in a Th17-dependent autoimmune Experimental autoimmune encephalomyelitis (EAE) model. Impaired Th17-differentiation was caused by overproduction of the immunosuppressive cytokine, IL-10. Increased IL-10 production in Nqo1-deficient Th17 cells was associated with elevated intracellular Reactive oxygen species (ROS) levels. Furthermore, overproduction of IL-10 in Th17 (ß) cells was responsible for the ROS-dependent increase of c-avian musculoaponeurotic fibrosarcoma (c-maf) expression, despite the lack of dependency of c-maf in Th17(23) cells. Taken together, the results reveal a novel role of NQO1 in promoting Th17 development through the suppression of ROS mediated IL-10 production.

Theoretical Model of the Far-Red-Light-Adapted Photosystem I Reaction Center of Cyanobacterium Acaryochloris marina Using Chlorophyll d and the Effect of Chlorophyll Exchange.

A theoretical model of the far-red-light-adapted photosystem I (PSI) reaction center (RC) complex of a cyanobacterium, Acaryochloris marina (AmPSI), was constructed based on the exciton theory and the recently identified molecular structure of AmPSI by Hamaguchi et al. (Nat. Commun., 2021, 12, 2333). A. marina performs photosynthesis under the visible to far-red light (400-750 nm), which is absorbed by chlorophyll d (Chl-d). It is in contrast to the situation of all the other oxygenic photosynthetic processes of cyanobacteria and plants, which contains chlorophyll a (Chl-a) that absorbs only 400-700 nm visible light. AmPSI contains 70 Chl-d, 1 Chl-d', 2 pheophytin a (Pheo-a), and 12 carotenoids in the currently available structure. A special pair of Chl-d/Chl-d' acts as the electron donor (P740) and two Pheo-a act as the primary electron acceptor A0 as the counterparts of P700 and Chl-a, respectively, of Chl-a-type PSIs. The exciton Hamiltonian of AmPSI was constructed considering the excitonic coupling strength and site energy shift of individual pigments using the Poisson-TrESP (P-TrESP) and charge density coupling (CDC) methods. The model was constructed to fit the experimentally measured spectra of absorption and circular dichroism (CD) spectra during downhill/uphill excitation energy transfer processes. The constructed theoretical model of AmPSI was further compared with the Chl-a-type PSI of Thermosynechococcus elongatus (TePSI), which contains only Chl-a and Chl-a'. The functional properties of AmPSI and TePSI were further examined by the in silico exchange of Chl-d by Chl-a in the models.

EGFR inhibition reverses epithelial­mesenchymal transition, and decreases tamoxifen resistance via Snail and Twist downregulation in breast cancer cells.

Tamoxifen resistance remains a major obstacle in the treatment of estrogen receptor (ER)­positive breast cancer. In recent years, the crucial role of the epithelial­mesenchymal transition (EMT) process in the development of drug resistance in breast cancer has been underlined. However, the central molecules inducing the EMT process during the development of tamoxifen resistance remain to be elucidated. In the present study, it was demonstrated that tamoxifen­resistant breast cancer cells underwent EMT and exhibited an enhanced cell motility and invasive behavior. The inhibition of snail family transcriptional repressor 1 (Snail) and twist family BHLH transcription factor 1 (Twist) reversed the EMT phenotype and decreased the tamoxifen resistance, migration and invasion of tamoxifen­resistant breast cancer cells. In addition, it was observed that the inhibition of epidermal growth factor receptor (EGFR) reversed the EMT phenotype in tamoxifen­resistant MCF7 (MCF­7/TR) cells via the downregulation of Snail and Twist. Notably, the EGFR inhibitor, gefitinib, decreased tamoxifen resistance, migration and invasion through the inhibition of Snail and Twist. On the whole, the results of the present study suggest that EGFR may be a promising therapeutic target for tamoxifen­resistant breast cancer. Moreover, it was suggested that gefitinib may serve as a potent novel therapeutic strategy for breast cancer patients, who have developed tamoxifen resistance.

PI3K/Akt/YAP signaling promotes migration and invasion of DLD-1 colorectal cancer cells.

Colorectal cancer (CRC) is one of the most prevalent malignant diseases and metastasis is the leading cause of poor prognosis in patients with CRC. Further knowledge of the molecular mechanism underlying metastasis in CRC and the identification of new therapeutic targets are needed. Yes-associated protein (YAP) is a transcriptional regulator that is important in tumorigenesis and tumor cell proliferation. The present study investigated whether YAP was crucial for CRC migration and invasion. The protein expression levels were detected via western blotting, and migration and invasion were analyzed by Transwell migration and invasion assays. Subsequently, YAP expression was silenced using small interfering RNA. The mRNA expression levels were detected via reverse transcription-quantitative PCR and cell viability was assessed via Trypan blue exclusion assay. The results revealed that YAP protein levels were associated with migration and invasion of CRC cells. Notably, YAP small interfering RNA inhibited the migration and invasion of DLD-1 cells. In addition, the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway inhibitor LY294002 suppressed the migration and invasion of DLD-1 cells by decreasing the expression of YAP. Notably, the present study demonstrated that verteporfin mediated the suppression of migration and invasion of DLD-1 cells due to the decreased expression of YAP. Therefore, targeting YAP may be valuable for developing therapeutic strategies against CRC, and verteporfin may be an effective therapy to suppress the migration and invasion of CRC.

Inhibition of yes-associated protein suppresses migration, invasion, and metastasis in non-small cell lung cancer in vitro and in vivo.

Non-small cell lung cancer (NSCLC) is a highly aggressive cancer with one of the most prevalent malignant tumors. Metastasis in NSCLC is the major cause of treatment failure and cancer-related deaths. Yes-associated protein (YAP) is a transcriptional coactivator regulated by the evolutionarily conserved Hippo signaling pathway that regulates organ size, growth, and regeneration. YAP is highly expressed in several malignant tumor types. Furthermore, YAP promotes tumor initiation and/or progression in various types of cancer. However, it is unclear whether YAP contributes to the metastasis in NSCLC and serves as a useful therapeutic target. Here, we investigated whether levels of YAP correlate with metastatic phenotype in NSCLC cells and serve as a useful therapeutic target. We found that high levels of YAP associate with high cell migration, invasion, and metastasis in NSCLC cell lines. Furthermore, YAP siRNA decreased the migration and invasion in NSCLC cells. Additionally, verteporfin, an agent used for the treatment of symptomatic polypoidal choroidal vasculopathy, decreased the expression of YAP and inhibited migration, invasion, and metastasis in NSCLC cells. Thus, the study suggests that targeting YAP may present a new avenue to develop therapeutics against metastasis in NSCLC and that verteporfin has potential molecular therapeutic strategy for the treatment of metastatic NSCLC.

Comparison between the Light-Harvesting Mechanisms of Type-I Photosynthetic Reaction Centers of Heliobacteria and Photosystem I: Pigment Site Energy Distribution and Exciton State.

The photosynthetic pigment system on the anoxygenic type-I reaction center of heliobacteria (hRC), which has a symmetrical structure, was analyzed. The excitonic coupling among all of the bacteriochlorophyll g (BChl-g) molecules and chlorophyll a (Chl-a) molecules and the site energy for each pigment were calculated using Poisson-TrESP and the charge density coupling (CDC) methods. The obtained theoretical model reproduced the optical absorption and circular dichroism spectra. It also interpreted the decay-associated spectra upon the photoselective laser excitation, which represent the ultrafast excitation energy migration process, better than the simpler hRC models that assumed constant pigment site energy shifts. Spatial movements of excitation energy on pigments on hRC upon the laser excitation were visualized. The energy dissipation by carotenoid molecules in hRC was also predicted. The hRC model was compared with the model of the reaction center of cyanobacterial photosystem I (PSI), which carries 95 Chl-a on the analogous type-I structure with significantly different amino-acid sequences, pigment species, and output redox powers. It is shown that the locations and site energy values of pigments in hRC resemble those in the core of PSI, except for the red-Chl-a sites, suggesting common functional mechanisms implicated in their evolution.

Comparison of cytologic findings between specimens with and without high-risk HPV infection in those with ASC-US judgement.

The objective of the study was to realize whether specific signatures for high-risk human papilloma virus (HPV) infection exist in the cytologic specimens with ASC-US judgement or not. The materials are 132 cytologic specimens with the diagnosis of ASC-US, including 56 cases with positive and 76 cases with negative HPV infection. Cytological findings are compared between two groups. Immature squamous metaplastic cells with nuclear atypia, SFT/IMT dyskaryotic cells, atypical parakeratosis, smudgy nuclei and multinucleated cells are the signature of high-risk HPV infection, whereas in the HPV(-) group immature metaplastic cells without atypia, moderately mature metaplastic cells without nuclear atypia and atrophic background are more popular. Instead, there are no differences on SFT/IMT background, microorganism infection and koilocytosis with or without nuclear atypia in both groups. The specific findings to confirm high-risk HPV infection are realized and the present results will contribute to decrease an unnecessary ASC-US judgement.

Immunomodulatory Mechanism of Acyclic Nucleoside Phosphates in Treatment of Hepatitis B Virus Infection.

BACKGROUND AND AIMS: Current treatment with nucleos(t)ide analogs (NUCs) safely controls the replication of hepatitis B virus (HBV) and improves prognosis in patients with HBV. However, the inability to completely clear HBV is problematic, and novel therapies are desired. It has been believed that all NUCs have similar functions to inhibit HBV reverse transcriptase. However, our recent findings that only acyclic nucleoside phosphonates (ANPs; adefovir dipivoxil and tenofovir disoproxil fumarate) had an additional effect of inducing interferon (IFN)-λ3 in the gastrointestinal tract suggests that ANPs are not only distinct from nucleoside analogs (lamivudine and entecavir) in their structures but also in their functions. Because enteric lipopolysaccharide (LPS) can cross the intestine and affect peripheral blood mononuclear cells (PBMCs), we hypothesized that orally administered ANPs could have further additional effects to modulate LPS-mediated cytokine profile in PBMCs. APPROACH AND RESULTS: This study showed that pretreatment of PBMCs, from either healthy volunteers or patients with HBV, with ANPs inhibited LPS-mediated interleukin (IL)-10 production, which reciprocally induced IL-12p70 and tumor necrosis factor-α production in a dose-dependent manner. Furthermore, the combination of IFN-α and ANPs synergistically enhanced LPS-mediated IL-12p70 production in PBMCs. Mechanistic analyses revealed that cellular metabolites of ANPs directly bound the Akt protein, inhibiting its translocation to the plasma membrane, thereby impairing Akt phosphorylation. Therefore, pretreatment of PBMCs with ANPs impairs LPS-mediated IL-10 production. CONCLUSIONS: Among NUCs, only ANPs have an additional pharmacological effect modulating LPS-mediated cytokine production, which is expected to produce favorable immune responses toward HBV elimination. This additional immunomodulation by ANPs in PBMCs, as well as IFN-λ3 induction in the gastrointestinal tract, provides insights into HBV treatment.

Excitonic Coupling on a Heliobacterial Symmetrical Type-I Reaction Center: Comparison with Photosystem I.

The excitonic couplings among 54 bacteriochlorophylls-g (BChl)-g, 4 BChl-g', and 2 Chl-aF pigments were calculated in the type-I homodimeric reaction center (RC) of Heliobacterium modesticaldum (hRC) and compared with those in the photosystem I (PSI) type-I heterodimeric RC. The advanced combination of transition charge of electrostatic potential (TrESP) with the Poisson equation (Poisson-TrESP), applied for the first time to the excitonic coupling calculation, gave a reliable model in contrast to a model calculated by simple standard dipole-dipole interaction approximation that was qualitatively valid for hRC but not for PSI. The simplest method for the calculation of the long-range contribution to the excitonic coupling on RCs is shown to be the TrESP method, which considers a distance- and orientation-independent local-field/screening correction factor. The excitonic couplings of the special pairs, P800 in hRC and P700 in PSI, are also calculated by the fragment excitation difference scheme at the configuration-interaction singles (CIS) level, which considers the charge-transfer characteristics of the relevant excitonic states. The calculation realized that the reported parameter values for P800 and P700 were better than the Poisson-TrESP calculation. Virtual exchanges between Chl-a and BChl-g on hRC and PSI indicated that the difference between hRC and PSI arises from the different electronic structures of Chl-a and BChl-g pigments themselves and the different arrangements on hRC and PSI. The contributions of excitonic couplings to the functional properties and evolutionary modifications of hRC and PSI are also discussed.

Theoretical Model of Exciton States and Ultrafast Energy Transfer in Heliobacterial Type I Homodimeric Reaction Center.

A simple theoretical model of exciton dynamics was proposed to interpret the fast excitation energy-transfer process in the type I homodimeric reaction center of Heliobacterium modesticaldum (hRC); this structure was recently identified and shown to resemble that of the plant/cyanobacterial photosystem I (PSI) reaction center. The exciton state model, which mainly relies on the geometries of 54 bacteriochlorophyll (BChl) g, 4 BChl- g', and 2 chlorophyll (Chl) a on hRC and assumes constant site energy values for the pigments, reproduced the absorption spectrum of hRC rather well. The model also enabled numerical analysis of the exciton dynamics on hRC, which can be compared with the decay-associated spectra obtained by the laser spectroscopy experiments. The model indicates that the stronger transition-dipole moment on BChl- g contributes to the faster energy transfer due to the higher coherency of the delocalized exciton states on hRC compared to that on PSI that arranges Chl- a at almost homologous locations.

NQO1 inhibits the TLR-dependent production of selective cytokines by promoting IκB-ζ degradation.

NAD(P)H:quinone oxidoreductase 1 (NQO1) protects cells against oxidative stress and toxic quinones. In this study, we found a novel role of NQO1 in suppressing Toll-like receptor (TLR)-mediated innate immune responses. NQO1-deficient macrophages selectively produced excessive amounts of IL-6, IL-12, and GM-CSF on LPS stimulation, and the deletion of NQO1 in macrophages exacerbated LPS-induced septic shock. NQO1 interacted with the nuclear IκB protein IκB-ζ, which is essential for the TLR-mediated induction of a subset of secondary response genes, including IL-6, and promoted IκB-ζ degradation in a ubiquitin-dependent manner. We demonstrated that PDLIM2, known as the ubiquitin E3 ligase, participates in NQO1-dependent IκB-ζ degradation. NQO1 augmented the association between PDLIM2 and IκB-ζ, resulting in increased IκB-ζ degradation. Collectively, this study describes a mechanism of the NQO1-PDLIM2 complex as a novel and important regulator in the innate immune signaling and suggests the therapeutic potential of NQO1 in TLR-mediated inflammation and disorders.

Cutting Edge: Nqo1 Regulates Irritant Contact Hypersensitivity against Croton Oil through Maintenance of Dendritic Epidermal T Cells.

Irritant contact dermatitis (ICD) is associated with local release of inflammatory mediators such as reactive oxygen species and regulated by various antioxidative enzymes and antioxidants. Although Nqo1 is involved in antioxidative reactions and detoxification, its role in ICD remains unknown. Nqo1-deficient mice exhibited augmented ear swelling accompanied by neutrophil infiltration in the croton oil-induced mouse ICD model. In the skin of Nqo1-deficient mice, Vγ5Vδ1+ dendritic epidermal T cells (DETCs), which are known to suppress ICD, were severely reduced. As the transfer of DETCs into Nqo1-deficient mice reversed an increased ICD response, loss of DETCs could account for the increased ICD. DETCs from Nqo1-deficient mice were sensitive to oxidative stress-induced cell death in vitro, and antioxidant NAC treatment in the ears of these mice rescued the number of DETCs and produced a normal ICD response. Taken together, the current results demonstrate that antioxidative enzyme Nqo1 regulates ICD through DETC maintenance.

Inquiring about insomnia may facilitate diagnosis of depression in the primary care setting.

AIM: Depression is often undiagnosed in primary care. Asking about sleep status is much easier than asking about mood. This study was conducted to examine the relation between insomnia and depression. METHODS: New patients aged 35-64 years were recruited from internal medicine clinics in Japan. Self-administered questionnaires were employed. Depression was evaluated by the Zung Self-Rating Depression Scale and the Profile of Mood States. Sleep status was investigated using the Pittsburgh Sleep Quality Index. Likelihood ratios of insomnia for depression were calculated. To assess the relation between insomnia and depression independent of confounding factors, adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using multiple logistic regression analyses. RESULTS: Among 598 subjects, 153 (25.6%) were assessed as having depression. 'Very bad sleep quality, with difficulty falling asleep within 30 min ≥3 times/week' showed a positive likelihood ratio of 20.36 (95%CI, 2.53-164) while 'not very good sleep quality' had a negative likelihood ratio of 0.32 (95%CI, 0.14-0.72). Adjusted for sex, age, underlying diseases, major life events, lifestyle habits, and relationship problems, significant OR for depression were observed for 'difficulty falling asleep within 30 min ≥3 times/week' (OR, 2.53; 95%CI, 1.07-5.98), 'waking up in the middle of the night or early morning ≥3 times/week' (OR, 3.09; 95%CI, 1.58-6.05), and 'fairly bad sleep quality' (OR, 3.65; 95%CI, 1.34-9.96). CONCLUSION: Inquiring about the weekly frequency of difficulty 'falling asleep within 30 min,' 'waking up in the middle of the night or early morning,' and 'sleep quality' may help to diagnose depression.

Hepatic aberrant glycosylation by N-acetylglucosaminyltransferase V accelerates HDL assembly.

Glycosylation is involved in various pathophysiological conditions. N-Acetylglucosaminyltransferase V (GnT-V), catalyzing ß1-6 branching in asparagine-linked oligosaccharides, is one of the most important glycosyltransferases involved in cancer and the immune system. Recent findings indicate that aberrant N-glycan structure can modify lipid metabolism. In this study, we investigated the effects of aberrant glycosylation by GnT-V on high-density lipoprotein cholesterol (HDL) assembly. We used GnT-V transgenic (Tg) mice and GnT-V Hep3B cell (human hepatoma cell line) transfectants. The study also included 96 patients who underwent medical health check-ups. Total serum cholesterol levels, particularly HDL-cholesterol (HDL-C) levels, were significantly increased in Tg vs. wild-type (WT) mice. Hepatic expression of apolipoprotein AI (ApoAI) and ATP-binding cassette subfamily A member 1 (ABCA1), two important factors in HDL assembly, were higher in Tg mice compared with WT mice. ApoAI and ABCA1 were also significantly elevated in GnT-V transfectants compared with mock-transfected cells. Moreover, ApoAI protein in the cultured media of GnT-V transfectants was significantly increased. Finally, we found a strong correlation between serum GnT-V activity and HDL-C concentration in human subjects. Multivariate logistic analyses demonstrated that GnT-V activity was an independent and significant determinant for serum HDL-C levels even adjusted with age and gender differences. Further analyses represented that serum GnT-V activity had strong correlation especially with the large-size HDL particle concentration. These findings indicate that enhanced hepatic GnT-V activity accelerated HDL assembly and could be a novel mechanism for HDL synthesis.