Next-generation probiotic candidates targeting intestinal health in weaned piglets: Both live and heat-killed Akkermansia muciniphila prevent pathological changes induced by enterotoxigenic Escherichia coli in the gut.

The use of next-generation probiotics (NGP) in pigs for combating diseases has been subject to limited research. Here we explored the potential of a well-known NGP candidate Akkermansia muciniphila targeting pig gut health. In the first screening experiment, we found that the abundance of A. muciniphila peaked at 14 d old but decreased at weaning (21 d old; P < 0.05), suggesting the weaning period may be an effective window for A. muciniphila intervention. Following that, 48 crossbred weaned pigs at 28 d old were randomly assigned to five groups: control (CON), high/low live A. muciniphila (HA/LA), and high/low heat-killed A. muciniphila (HIA/LIA). From 1 to 28 d old, the CON group received gastric infusion of anaerobic sterile saline every other day; the HA and LA groups were gavaged every other day with 1 × 1010 CFU/5 mL and 5 × 108 CFU/5 mL live A. muciniphila, respectively; and the HIA and LIA groups were gavaged every other day with 1 × 1010 CFU/5 mL and 5 × 108 CFU/5 mL heat-killed A. muciniphila, respectively. At d 29, pigs in the CON group were randomly and equally divided into two groups, one of which was named the enterotoxigenic Escherichia coli (ETEC) group, and all groups except CON received a 5-d ETEC challenge. The supplementation of A. muciniphila numerically reduced the diarrhea rate of weaned pigs compared to the pigs that only received the ETEC challenge (P = 0.57), but the LIA group had a higher diarrhea rate than the CON group (P < 0.05). Consistent with this, the supplementation of A. muciniphila improved the small intestinal morphology and structure, proportion of CD4+ T lymphocytes in the blood, as well as the expression of genes related to intestinal barrier and antioxidant indices of pigs with ETEC challenge, especially for the LA group (P < 0.05). Meanwhile, A. muciniphila supplementation reduced the expression of ETEC virulence factor genes in the ileum and colon of pigs challenged by ETEC (P < 0.05). Therefore, A. muciniphila may protect the intestinal health of weaned piglets from damage caused by ETEC infection, but the effect may vary depending on the concentration and activity of A. muciniphila.

New Target for Minoxidil in the Treatment of Androgenetic Alopecia.

Objective: To investigate the mechanism of minoxidil in treating androgenetic alopecia (AGA). Methods: The mechanism of action of minoxidil on AGA was first systematically investigated from the viewpoint of network pharmacology, including minoxidil-AGA target prediction, protein-protein interaction (PPI) network analysis, molecular docking and enrichment analysis of targets related to minoxidil and AGA, and dermal papilla cell assays to confirm the viability of prediction. Results: The combined analysis revealed that minoxidil treatment of AGA not only acts on androgenic receptors (AR) but also on 2 new targets, steroid 17-alpha-hydroxylase/17,20 lyase (CYP17A1) and aromatase (CYP19A1). The biological processes linked to these targets were concentrated on several pathways, including enzymes and hormones. Further experiments have revealed that minoxidil suppresses the expression of AR and CYP17A1, boosts the activity of CYP19A1, decreases the formation and binding of dihydrotestosterone, and enhances the production of estradiol. Through these changes, minoxidil acts as a treatment for AGA. Conclusion: Minoxidil may act by altering hormonal and enzymatic pathways. Our study finds two new targets (CYP17A1, CYP19A1) of minoxidil and demonstrates that minoxidil inhibits AR. These targets may provide new ideas for drug research.

MAT2A inhibits the ferroptosis in osteosarcoma progression regulated by miR-26b-5p.

Osteosarcoma (OS) is the most frequent primary malignant bone tumor. Ferroptosis, a form of regulated cell death, is a key tumor suppression mechanism. Although methionine adenosyltransferase II alpha (MAT2A) has been reported to inhibit several tumor cells, it is unclear whether inhibition of MAT2A in OS cells can reduce ferroptosis. CCK-8, flow cytometry, and Transwell assays were performed to evaluate cell viability, cell apoptosis/cycle, and cell migration, respectively. The levels of ferrous iron and glutathione (GSH) levels in cells were measured to evaluate the degree of cell ferroptosis. Western blot analysis was performed to detect protein levels of MAT2A, p-STAT3 (Ser727)/STAT3, and solute carrier family 7 member 11 (SLC7A11) in OS cells. MAT2A was significantly upregulated in OS specimens and high MAT2A expression was associated with a poorer prognosis in OS patients. shRNA targeting MAT2A significantly increased OS cell apoptosis, triggered cell cycle arrest in the G2 phase, and attenuated migration ability in vitro. MAT2A depletion dramatically inhibited tumor progression of OS in vivo. Overexpression of MAT2A rescued the tumor inhibition caused by miR-26b-5p. MAT2A knockdown promoted OS cell ferroptosis. miR-26b-5p/MAT2A regulates tumor malignant progression and OS cell ferroptosis by controlling p-STAT3 and SLC7A11 expressions. Taken together, our study displayed that miR-26b-5p/MAT2A triggers ferroptosis in OS cells by increasing intracellular ferrous iron levels and inhibiting the STAT3/SLC7A11 axis. Our results reveal a MAT2A-mediated ferroptosis defense mechanism used by OS cells and propose a potential ferroptosis-inducing strategy for the treatment of OS patients.

A Cone Beam Computed Tomography Analysis of Bone Volume Variations of Extra-alveolar Region Based on Sex, Age, Vertical and Sagittal Facial Patterns.

OBJECTIVES: The goal of this study is to measure mandibular buccal shelf (MBS) concerning angulation, bone volume, and cortical bone volume as well as bone depth and cortical bone depth of infrazygomatic crest (IZC) via cone beam computed tomography and evaluate the measurements according to sex, age, vertical, and sagittal facial types. MATERIALS AND METHODS: This study collected lateral cephalograms and cone beam computed tomography scans from 100 individuals, which were used to observe angulation, bone and cortical bone volume entailing width and depth of MBS as well as the depth of IZC. FH-MP (mandibular plane angle) and A point-Nasion-B point were adopted to determine vertical and sagittal facial patterns respectively. RESULTS: Bone widths at 6 mm and 11 mm to cementoenamel junction (CEJ) and cortical bone width at 6 mm to CEJ in MBS showed significant sex differences, while bone depths and cortical bone depths in IZC show significant age difference( P <0.05). Bone width and cortical bone width at 6 mm to CEJ at the mesial root and 11 mm to CEJ at both roots as well as angulations of MBS in the mandibular first molar region, bone depth and cortical bone depth at the maxillary first molar distal buccal root, and the proximity region were all correlated to FH-MP ( P <0.05). CONCLUSIONS: Short-faced individuals of Asian ethnicity tend to have greater bone width, greater projection in MBS, and greater bone depth in the posterior region of IZC. The optimal implant sites are 11 mm apical to CEJ at the mandibular second molar distal root and 65° at the maxillary first molar mesial root.

Nested Phosphorothioated Hybrid Primer-Mediated Isothermal Amplification for Specific and Dye-Based Subattomolar Nucleic Acid Detection at Low Temperatures.

Developing dye-based isothermal nucleic acid amplification (INAA) at low temperatures such as 37 °C remains a technical challenge. Here, we describe a nested phosphorothioated (PS) hybrid primer-mediated isothermal amplification (NPSA) assay which only utilizes EvaGreen (a DNA-binding dye) to achieve specific and dye-based subattomolar nucleic acid detection at 37 °C. The success of low-temperature NPSA essentially depends on employing Bacillus smithii DNA polymerase, a strand-displacing DNA polymerase with wide range of activation temperature. However, the NPSA's high efficiency entails nested PS-modified hybrid primers and the additives of urea and T4 Gene 32 Protein. To address the inhibition of urea on reverse transcription (RT), one-tube two-stage recombinase-aided RT-NPSA (rRT-NPSA) is established. By targeting human Kirsten rat sarcoma viral (KRAS) oncogene, NPSA (rRT-NPSA) stably detects 0.2 aM of KRAS gene (mRNA) within 90 (60) min. In addition, rRT-NPSA possesses subattomolar sensitivity to detect human ribosomal protein L13 mRNA. The NPSA/rRT-NPSA assays are also validated to obtain consistent results with PCR/RT-PCR methods on qualitatively detecting DNA/mRNA targets extracted from cultured cells and clinical samples. As a dye-based, low-temperature INAA method, NPSA inherently facilitates the development of miniaturized diagnostic biosensors.

Pterostilbene supresses inflammation-induced melanoma metastasis by impeding neutrophil elastase-mediated thrombospondin-1 degradation.

Objective: Chronic inflammation plays a fatal role in tumor metastasis. Pterostilbene (PTE) is a natural dimethylated analogue of resveratrol with anticancer and anti-inflammatory activities. This study aimed to investigate the inhibitory effect of PTE on inflammation-associated metastasis and explore the underlying mechanisms. Methods: Lipopolysaccharide (LPS)-induced lung inflammation and melanoma metastasis models were established in mice. After PTE treatment for four weeks, the organ index, histological changes, proinflammatory cytokines, and the expression and activity of neutrophil elastase (NE), a biomarker of neutrophil influx in the lungs, were analysed. Additionally, direct effects of PTE on NE-induced B16 cell migration were explored in wound healing and Transwell assays, and the expression of thrombospondin-1 (TSP-1) and epithelial-mesenchymal transition (EMT) markers were also detected. Results: PTE obviously attenuated the LPS-induced metastasis of circulatory B16 cells to lungs by reducing the number of metastatic nodules on the lung surfaces and the lung weight/body weight ratio. PTE treatment also significantly reduced LPS-activated increase levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the lungs of tumor-bearing mice. In addition, increased expression and enzyme activity of NE and decreased expression of TSP-1 were observed, and these were blocked by PTE. In vitro, PTE at concentrations without cytotoxicity also markedly suppressed NE-triggered B16 cell migration, prevented NE-induced TSP-1 proteolysis and reversed the expression of vimentin, N-cadherin and E-cadherin. Conclusion: PTE could block inflammation-enhanced tumor metastasis, and the underlying mechanism might be associated with the inhibition of NE-mediated TSP-1 degradation.

Tumor cell-released LC3-positive EVs promote lung metastasis of breast cancer through enhancing premetastatic niche formation.

Most breast cancer-related deaths are caused by metastasis in vital organs including the lungs. Development of supportive metastatic microenvironments, referred to as premetastatic niches (PMNs), in certain distant organs before arrival of metastatic cells, is critical in metastasis. However, the mechanisms of PMN formation are not fully clear. Here, we demonstrated that chemoattractant C-C motif chemokine ligand 2 (CCL2) could be stimulated by heat shock protein 60 (HSP60) on the surface of murine 4 T1 breast cancer cell-released LC3+ extracellular vesicles (LC3+ EVs) via the TLR2-MyD88-NF-κB signal cascade in lung fibroblasts, which subsequently promoted lung PMN formation through recruiting monocytes and suppressing T cell function. Consistently, reduction of LC3+ EV release or HSP60 level or neutralization of CCL2 markedly attenuated PMN formation and lung metastasis. Furthermore, the number of circulating LC3+ EVs and HSP60 level on LC3+ EVs in the plasma of breast cancer patients were positively correlated with disease progression and lung metastasis, which might have potential value as biomarkers of lung metastasis in breast cancer patients (AUC = 0.898, 0.694, respectively). These findings illuminate a novel mechanism of PMN formation and might provide therapeutic targets for anti-metastasis therapy for patients with breast cancer.

Single and combined 1064 nm Q-switched Nd: YAG laser therapy in melasma: A meta-analysis.

PURPOSE: This article attempted to describe the efficacy and safety of 1064QNYL in combination with other treatments for refractory melasma. METHODS: Two researchers independently retrieved randomized controlled trials (RCTs) according to inclusion and exclusion criteria. Primary outcome was evaluated with MASI and mMASI scores in control group and experiment group. The secondary outcome was evaluated with MI scores. We calculated 95% CI of standardized mean difference (SMD) and heterogeneity of the included literature by Higgins I2 test, and assessed publication bias by Funnel plots, Egger's, and Begg's tests. RESULTS: A total of 12 articles including 322 subjects were analyzed. Experiment group was treated with 1064QNYL combined with single treatment (e.g., PDL, IPL, RF, and TA). Control group was treated with 1064QNYL alone. A greater reduction of Melasma Area and Severity Index (MASI)/modified Melasma Area and Severity Index (mMASI) scores were shown in experiment group than that in control group at the end of the treatment (SMD, -0.37; 95% CI -0.70 to -0.04, p = 0.03, I2  = 33%). The SMD of MI scores further supported this conclusion by -0.32 (95% CI -0.63 to -0.02, p = 0.04, I2  = 27%). As for adverse events (AEs), combined treatment gave rise to more mild burning, stinging, and erythema that resolved spontaneously. Several studies reported focal purpura, punctate leukoderma, hyperpigmentation, hypopigmentation, and so on. CONCLUSION: Combined 1064QNYL treatment was better than single laser treatment, with the highest short-term benefit and long-term follow-up to maintain the effect in favor of combined treatment.

High expression of RIPK2 is associated with Taxol resistance in serous ovarian cancer.

BACKGROUND: Taxol resistance in serous ovarian cancer is responsible for its poor prognosis, yet the underlying mechanism is still poorly understood. Thus, we probed the mechanism of Taxol resistance in serous ovarian cancer with multiple bioinformatic methods to provide novel insights into potential therapies. METHODS: The differentially expressed genes (DEGs) in Taxol-sensitive and Taxol-resistant cell lines and their relationship with the overall survival (OS) and progression-free interval (PFI) of ovarian cancer patients were analyzed using gene expression datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The role of receptor interacting serine/threonine kinase 2 (RIPK2) was validated via identification of its coexpressed genes, functional analysis and generation of a protein-protein interaction (PPI) network. The single sample gene set enrichment analysis (ssGSEA) was used to explore immune infiltration, and genomic alterations of RIPK2 were also analyzed via cBio Cancer Genomics Portal (cBioProtal). RESULTS: RIPK2 was highly expressed in Taxol resistant ovarian cancer cell lines, and its high expression was also linked with shorter OS and PFI in serous ovarian cancer patients. The PPI network analysis and pathway analysis demonstrated that RIPK2 might participate in the positive regulation of NF-κB transcription factor activity. RIPK2 expression was related to tumor microenvironment alterations, which might participate in the formation of Taxol resistance. CONCLUSIONS: Our studies suggested that high expression of RIPK2 is related to Taxol resistance in serous ovarian cancer, and that RIPK2 induces Taxol resistance through NOD1/RIPK2/NF-κB inflammatory pathway activation and tumor microenvironment changes.

Metabolizable pH/H2O2 dual-responsive conductive polymer nanoparticles for safe and precise chemo-photothermal therapy.

Conductive polymers with high near-infrared absorbance, have attracted considerable attention in the design of intelligent nanomedicines for cancer therapy, especially chemo-photothermal therapy. However, the unknown long-term biosafety of conductive polymers in vivo due to non-degradability hinders their clinic application. Herein, a H2O2-triggered degradable conductive polymer, polyacrylic acid (PAA) stabilized poly(pyrrole-3-COOH) (PAA@PPyCOOH), is fabricated to form nanoparticles with doxorubicin (DOX) for safe and precise chemo-phototherapy. The PAA@PPyCOOH was found to be an ideal photothermal nano-agent with good dispersity, excellent biocompatibility and high photothermal conversion efficiency (56%). After further loading of doxorubicin (DOX), PAA@PPyCOOH@DOX demonstrates outstanding photothermal performance, as well as pH/H2O2 dual-responsive release of DOX in tumors with an acidic and overexpressed H2O2 microenvironment, resulting in superior chemo-photothermal therapeutic effects. The degradation mechanism of PAA@PPyCOOH is proposed to be the ring-opening reaction between the pyrrole-3-COOH unit and H2O2. More importantly, the nanoparticles can be specifically degraded by excess H2O2 in tumor, and the degradation products were confirmed to be excreted via urine and feces. In vivo therapeutic evaluation of chemo-photothermal therapy reveals tumor growth of 4T1 breast cancer model is drastically inhibited and no apparent side-effect is detected, thus indicating substantial potential in clinic application.

Multifunctional Liposomes Enable Active Targeting and Twinfilin 1 Silencing to Reverse Paclitaxel Resistance in Brain Metastatic Breast Cancer.

Paclitaxel (PTX) is a first-line chemotherapeutic drug for breast cancer, but PTX resistance often occurs in metastatic breast cancer. In addition, due to the poor targeting of chemotherapeutic drugs and the presence of the blood-brain barrier (BBB), it is hard to effectively treat brain metastatic breast cancer using paclitaxel. Thus, it is urgent to develop an effective drug delivery system for the treatment of brain metastatic breast cancer. The current study found that TWF1 gene, an epithelial-mesenchymal transition-associated gene, was overexpressed in brain metastatic breast cancer (231-BR) cells and was associated with the PTX resistance of 231-BR cells. Knockdown of TWF1 by small interference RNA (siRNA) in 231-BR cells could effectively increase the sensitivity of brain metastatic breast cancer cells to paclitaxel. Then, a liposome-based drug delivery system was developed for PTX delivery across BBB, enhancing PTX sensitivity and brain metastases targeting via BRBP1 peptide modification. The results showed that BRBP1-modified liposomes could effectively cross the BBB, specifically accumulate in brain metastases, and effectively interfere TWF1 gene expression in vitro and in vivo, and thus they enhanced proliferation inhibition, cell cycle arrest, and apoptosis induction, thereby inhibiting the formation and growth of brain metastases. In summary, our results indicated that BRBP1-modified and PTX- and TWF1 siRNA-loaded liposomes have the potential for the treatment of brain metastatic breast cancer, which lays the foundation for the development of a new targeted drug delivery system.

MiR34a Regulates Neuronal MHC Class I Molecules and Promotes Primary Hippocampal Neuron Dendritic Growth and Branching.

In the immune system, Major Histocompatibility Complex class I (MHC-I) molecules are located on the surface of most nucleated cells in vertebrates where they mediate immune responses. Accumulating evidence indicates that MHC-I molecules are also expressed in the central nervous system (CNS) where they play important roles that are significantly different from their immune functions. Classical MHC-I molecules are temporally and spatially expressed in the developing and adult CNS, where they participate in the synaptic formation, remodeling and plasticity. Therefore, clarifying the regulation of MHC-I expression is necessary to develop an accurate understanding of its function in the CNS. Here, we show that microRNA 34a (miR34a), a brain enriched noncoding RNA, is temporally expressed in developing hippocampal neurons, and its expression is significantly increased after MHC-I protein abundance is decreased in the hippocampus. Computational algorithms identify putative miR34a target sites in the 3'UTR of MHC-I mRNA, and here we demonstrate direct targeting of miR34a to MHC-I mRNA using a dual-luciferase reporter assay system. MiR34a targeting can decrease constitutive MHC-I expression in both Neuro-2a neuroblastoma cells and primary hippocampal neurons. Finally, miR34a mediated reduction of MHC-I results in increased dendritic growth and branching in cultured hippocampal neurons. Taken together, our findings identify miR34a as a novel regulator of MHC-I for shaping neural morphology in developing hippocampal neurons.

Development of an immunogenomic landscape for the competing endogenous RNAs network of peri-implantitis.

BACKGROUND: Peri-implantitis is an inflammation that occurs around the implant, resulting in varying degrees of inflammatory damage to the soft and hard tissues. The characteristic criterion is the loss of the supporting bone in an inflammatory environment. However, the specific mechanisms and biomarkers involved in peri-implantitis remain to be further studied. Recently, competing endogenous RNAs (ceRNA) and immune microenvironment have been found to play a more important role in the inflammatory process. In our study, we analyzed the expression of immune related microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and message RNAs (mRNAs) in peri-implantitis by analyzing GSE33774 and GSE57631. METHODS: In this study, we explored the expression profile data of immune-related lncRNAs, miRNAs and mRNAs, and constructed immune-related ceRNA network involved in the pathogenesis of peri-implantitis. In addition, the CIBERSORT was used to evaluate the content of immune cells in normal tissues and peri-implantitis to detect the immune microenvironment of peri-implantitis. RESULTS: In the analysis, 14 DElncRNAs, 16 DEmiRNAs, and 18 DEmRNAs were used to establish an immune related ceRNA network and the immune infiltration patterns associated with peri-implantitis was discovered. Through the mutual verification of the two datasets, we found that GSK3B and miR-1297 may have important significance in the immune microenvironment and pathogenesis of peri-implantitis and GSK3B was closely related to four types of immune cells, especially with the highest correlation with resting mast cells (P = 0.0003). CONCLUSIONS: Through immune-related ceRNA network, immune-related genes (IRGs) and immune cell infiltration can further comprehensively understand the pathogenesis of peri-implantitis, which built up an immunogenomic landscape with clinical significance for peri-implantitis.

Targeted NIRF/MR dual-mode imaging of breast cancer brain metastasis using BRBP1-functionalized ultra-small iron oxide nanoparticles.

Tumor metastasis to brain is the main clinical manifestation of patients with advanced breast cancer, leading to poor survival prognosis. In order to detect the early incidence of brain metastasis, it is urgent to develop hypersensitive contrast agents for multimode imaging. In this study, PEG-phospholipids coated, a phage play derived peptide, BRBP1 peptide modified ultra-small iron oxide nanoparticles were prepared for targeted NIRF and MR imaging of breast cancer brain metastasis. The nanoparticles showed 10 nm core-shell, high relaxivity values and photon emission efficiency in vitro. The nanoparticles offered a T2 contrast imaging effect and near-infrared fluorescent signal enhancement. Compared with control peptide modified nanoparticles, the MR/NIRF imaging signal of BRBP1-modified nanoparticles in tumor tissue was significantly enhanced, which should be induced by the targeting ability of BRBP1 peptide. These results indicated that BRBP1-SPIO@mPEG (DiR) nanoparticles could be applied as an effective targeted delivery system for diagnosis of breast cancer brain metastasis.

The antitumor molecular mechanism of Alisma orientalis with c-myc DNA: multi-spectroscopic analysis and molecular simulation.

We prepared extracts of Alisma orientalis from Sichuan and Fujian Province, China. Based on the ratio of alisol B 23-acetate (23B) to alisol A 24-acetate (24A) in two Alisma orientalis extracts, we prepared two mixtures of 24A and 23B (24A:23B = 1:3 or 1:10). The antitumor molecular mechanism of the monomers 24A and 23B, the two mixtures and the effective components of Alisma orientalis from different habitats were studied. The MTT assay suggested that the difference in the antitumor activity of Alisma orientalis from different habitats was correlated to the ratio of 24A to 23B. The multi-spectroscopic analysis suggested that the effective components, the monomers and mixtures interacted with c-myc DNA in a partial intercalation manner. The binding strength of the alisol acetates to c-myc DNA was consistent with the anticancer activity, indicating that c-myc DNA was the anticancer target. The molecular simulation indicated that the mixtures were all directly bound to different base pairs of c-myc DNA for a superimposed effect, which led to the binding strength of the mixtures to c-myc DNA was stronger than that of the monomers. The molecules in the 1:3 mixture were all bound to different base pairs of c-myc DNA. However, for the 1:10 mixture, seven molecules of 23B bound to the side chain of 24A, resulting in the mixture with a long chain structure which increased the steric hindrance of 24A. As a result, affinity between 24A and c-myc DNA in the 1:10 mixture was weaker than that in the 1:3 mixture. [Formula: see text] The antitumor molecular mechanism of the alisol monomers 24A and 23B, the mixtures with different proportions and the effective components of Alisma orientalis from different habitats were studied. The order of the antitumor activity was as follows: Sichuan > Fujian, 24A-23B (1:3) > 24A-23B (1:10) > 23B > 24A. The antitumor activity of Alisma orientalis from different habitats was consistent with the mixtures which were designed according to the contents of the active ingredients of the medicinal materials, indicating that the antitumor activity of Alisma orientalis from Sichuan is better than that from Fujian which is related to the contents of 24A and 23B and the proportion of 1:3 is better than 1:10. The binding strength of the mixtures to c-myc DNA was consistent with the anticancer activity. The mixtures were all directly bound to different base pairs of c-myc DNA for a superimposed effect, which led to the strength of the interaction of the mixtures to c-myc DNA was stronger than that of the monomers. For the 24A-23B (1:3) mixture, the four small molecules bound to c-myc DNA directly and interacted with different base pairs of c-myc DNA. While for the 24A-23B (1:10) mixture, 24A and three 23B molecules interacted with c-myc DNA, the remaining seven 23B molecules bound to the side chain of 24A, which increased the steric hindrance. The binding of the mixture to c-myc DNA was decreased. Communicated by Ramaswamy H. Sarma.

Neuronal NLRC5 regulates MHC class I expression in Neuro-2a cells and also during hippocampal development.

Major histocompatibility Complex class I (MHC I) molecules are ubiquitously expressed, being found in most nucleated cells, where they are central mediators of both the adaptive and innate immune responses. Recent studies have shown that MHC I are also expressed in the developing brain where they participate in synapse elimination and plasticity. Up-regulation of MHC I within the developing brain has been reported, however, the mechanism(s) regulating this developmental up-regulation of neuronal MHC I remains unknown. Here, we show NLR family CARD domain containing 5 (NLRC5), a newly identified member of the NLR family, is widely expressed in hippocampal neurons, and the expression pattern of NLRC5 coincides with increased MHC I mRNA in the developing hippocampus. Using a luciferase assay in Neuro-2a cells we demonstrate that NLRC5 can induce the activation of MHC I and this induction requires the W/S-X-Y motif. Further studies show that transcription factors regulatory factor X (RFX) and CREB1, which bind to X1 and X2 box, are crucial for NLRC5-mediated induction. Moreover immunoprecipitation experiments reveal that NLRC5 interacts with RFX subunits RFX5 and RFXANK. Knockout of Nlrc5 dramatically impairs basal expression of MHC I in mouse hippocampus. Taken together, our findings identify NLRC5 as a key regulator of MHC I up-regulation in the developing hippocampus and suggest an important role for NLRC5 in neurons. Cover Image for this issue: doi: 10.1111/jnc.14729.

Poly(norepinephrine)-coated FeOOH nanoparticles as carriers of artemisinin for cancer photothermal-chemical combination therapy.

The photothermal-chemical combination therapy is a promising approach for cancer treatment, however, chemotherapy often causes severe toxic and side effects on normal tissues. Herein, tumor-specific FeOOH@PNE-Art nanoparticles were fabricated via coating poly(norepinephrine) (PNE) on FeOOH nanoparticles, followed by loading of artemisinin (Art). The as-prepared nanoparticles exhibited excellent biocompatibility, strong near-infrared (NIR) absorbance and pH-responsive synchronous release of Art and iron ions. The released iron ions could not only supply iron ions in cancer cells which mediate endoperoxide bridge cleavage of Art and generate reactive oxygen species (ROS), but also react with H2O2 at tumour sites via the Fenton reaction and produce hydroxyl radicals, inducing a tumour-specific killing. Moreover, owing to the synchronous release of Art and iron ions as well as the low leakage of iron ions, FeOOH@PNE-Art nanoparticles showed extremely low toxicity to normal tissue. Under NIR light irradiation, the tumours in FeOOH@PNE-Art injected mice were thoroughly eliminated after 7 days of treatment and no tumour recurrence was found 30 days after treatment, manifesting very high efficacy of combination therapy.

Glutathione de novo synthesis but not recycling process coordinates with glutamine catabolism to control redox homeostasis and directs murine T cell differentiation.

Upon antigen stimulation, T lymphocytes undergo dramatic changes in metabolism to fulfill the bioenergetic, biosynthetic and redox demands of proliferation and differentiation. Glutathione (GSH) plays an essential role in controlling redox balance and cell fate. While GSH can be recycled from Glutathione disulfide (GSSG), the inhibition of this recycling pathway does not impact GSH content and murine T cell fate. By contrast, the inhibition of the de novo synthesis of GSH, by deleting either the catalytic (Gclc) or the modifier (Gclm) subunit of glutamate-cysteine ligase (Gcl), dampens intracellular GSH, increases ROS, and impact T cell differentiation. Moreover, the inhibition of GSH de novo synthesis dampened the pathological progression of experimental autoimmune encephalomyelitis (EAE). We further reveal that glutamine provides essential precursors for GSH biosynthesis. Our findings suggest that glutamine catabolism fuels de novo synthesis of GSH and directs the lineage choice in T cells.

Modulation of the gamma-secretase activity as a therapy against human hepatocellular carcinoma.

OBJECTIVE: Hepatocellular carcinoma (HCC) is the fifth most common tumor worldwide. The discovery of new therapies against HCC is highly dependable on finding molecules which play essential roles in cancer development. The objective of this study was to evaluate the activity of gamma secretase (γ-secretase), and the antitumor effects of a γ-secretase inhibitor (GSI) in HCC. METHODS: The expression of presenilin 1 (PS1), a core component of γ-secretase, was examined by Western blot. Activity of γ-secretase was measured by a luciferase-based reporter system, and cancer cells were transfected either with PS1 dominant negative mutant (PS1D385A) or treated with GSI. RESULTS: Expression of PS1 was increased in HCC tissue and several HCC cell lines, which were accompanied by elevated γ-secretase activity. Cell colony formation and cell proliferation were decreased upon treatment with GSI but not with PS1D385A transfection. CONCLUSION: GSIs may be appealing candidates for the development of new therapies against HCC.

MYCN drives glutaminolysis in neuroblastoma and confers sensitivity to an ROS augmenting agent.

Heightened aerobic glycolysis and glutaminolysis are characteristic metabolic phenotypes in cancer cells. Neuroblastoma (NBL), a devastating pediatric cancer, is featured by frequent genomic amplification of MYCN, a member of the Myc oncogene family that is primarily expressed in the early stage of embryonic development and required for neural crest development. Here we report that an enriched glutaminolysis gene signature is associated with MYCN amplification in children with NBL. The partial knockdown of MYCN suppresses glutaminolysis in NBL cells. Conversely, forced overexpression of MYCN in neural crest progenitor cells enhances glutaminolysis. Importantly, glutaminolysis induces oxidative stress by producing reactive oxygen species (ROS), rendering NBL cells sensitive to ROS augmentation. Through a small-scale metabolic-modulator screening, we have found that dimethyl fumarate (DMF), a Food and Drug Administration-approved drug for multiple sclerosis, suppresses NBL cell proliferation in vitro and tumor growth in vivo. DMF suppresses NBL cell proliferation through inducing ROS and subsequently suppressing MYCN expression, which is rescued by an ROS scavenger. Our findings suggest that the metabolic modulation and ROS augmentation could be used as novel strategies in treating NBL and other MYC-driven cancers.