MAFLD-related hepatocellular carcinoma: Exploring the potent combination of immunotherapy and molecular targeted therapy.

Hepatocellular carcinoma (HCC) is a common cause of cancer-related mortality and morbidity globally, and with the prevalence of metabolic-related diseases, the incidence of metabolic dysfunction-associated fatty liver disease (MAFLD) related hepatocellular carcinoma (MAFLD-HCC) continues to rise with the limited efficacy of conventional treatments, which has created a major challenge for HCC surveillance. Immune checkpoint inhibitors (ICIs) and molecularly targeted drugs offer new hope for advanced MAFLD-HCC, but the evidence for the use of both types of therapy in this type of tumour is still insufficient. Theoretically, the combination of immunotherapy, which awakens the body's anti-tumour immunity, and targeted therapies, which directly block key molecular events driving malignant progression in HCC, is expected to produce synergistic effects. In this review, we will discuss the progress of immunotherapy and molecular targeted therapy in MAFLD-HCC and look forward to the opportunities and challenges of the combination therapy.

METS-IR/HOMA-IR and MAFLD in U.S. adults: dose-response correlation and the effect mediated by physical activity.

OBJECTIVES: Metabolic dysfunction-associated fatty liver disease (MAFLD), a globally prevalent disease, is closely linked to insulin resistance (IR). Physical activity (PA) is closely linked to both MAFLD and IR. We aim to explore the dose-response relationship between metabolic score for IR (METS-IR)/homeostasis model assessment of IR (HOMA-IR) and MAFLD, and investigate the relationship between PA, IR and MAFLD. METHODS: Participants from the NHANES study were included in this cross-section study. Logistic regression and the receiver operating characteristic were used to assess the predictive performance of METS-IR/HOMA-IR for MAFLD. Restrictive cubic splines were performed to visualize their dose-response relationship. Decision tree analysis was used to identify high-risk populations of MAFLD. PA's mediating effect in the association between METS-IR/HOMA-IR and MAFLD was also examined. RESULTS: Of all 1,313 participants, 693 had MAFLD (52.78%). There were a positive association between METS-IR (OR = 1.162, 95% CI = 1.126-1.199) and HOMA-IR (OR = 1.630, 95% CI = 1.431-1.856) and MAFLD risk. The AUCs of the METS-IR and HOMA-IR were 0.831 (0.809, 0.853) and 0.767 (0.741, 0.791), respectively, with significantly different predictive performance (P < 0.001). Adding METS-IR/HOMA-IR to the basic model greatly improved the statistical significance for MAFLD. Five high-risk subgroups were identified for MAFLD. PA mediated about 0.81% and 0.78% (indirect effect/total effect) in the association between METS-IR/HOMA-IR and MAFLD. CONCLUSIONS: MAFLD risk might be predicted by METS-IR/HOMA-IR, among which METS-IR performed better. And PA mediated the association between them. More attention should be paid to the therapeutic effect of lifestyle changes on MAFLD. HIGHLIGHTS: 1. Positive associations were found between METS-IR and HOMA-IR and MAFLD risk. 2. METS-IR has better predictive performance for MAFLD risk than HOMA-IR. 3.Two high-risk subgroups were identified for MAFLD by METS-IR: individuals with METS-IR ≥ 40; Hispanic black individuals with 34 ≤ METS-IR < 40 and aged ≥ 46. 4. In the significant association between METS-IR/HOMA-IR and MAFLD, about 0.81% and 0.78% (indirect effect/total effect), respectively, were mediated by physical activity.

Knowledge atlas of white matter microstructure: a bibliometric analysis.

Background: White matter microstructure is valued for being an indicator of neural network integrity, which plays an indispensable role in the execution of advanced brain functions. Although the number of publications has increased in the past 10 years, no comprehensive analysis has yet been conducted of this field. Therefore, this study aimed to identify the research hotspots and trends in research on white matter microstructure using a bibliometric analysis of the related literature published from 2013 to 2022. Methods: VOSviewer and CiteSpace were used to objectively analyze the research articles concerning white matter microstructure, which were retrieved from the Web of Science Core Collection (WoSCC). Results: A total of 5,806 publications were obtained, with the number of published articles increasing annually over the past decade. The United States, China, the United Kingdom, and Canada maintained the top positions worldwide and had strong cooperative relationships. The top institution and journal were Harvard Medical School and Neuroimage, respectively. Alexander Leemans, Marek Kubicki, and Martha E Shenton were the most productive authors. Thematic keywords mainly included "diffusion tensor imaging" (DTI), "white matter integrity", and "connectivity". The keyword analysis revealed that DTI has a critical role in detecting white matter microstructure integrity and that fractional anisotropy is the main parameter in the assessment process. Keyword burst detection identified four research hotspots: movement, distortion correction, voxelwise analysis, and fixel-based analysis. Conclusions: This bibliometric analysis provided a systematic understanding of the research on white matter microstructure and identified the current frontiers. This may help clinicians and researchers comprehensively identify hotspots and trends in this field.

Glyphosate Disorders Soil Enchytraeid Gut Microbiota and Increases Its Antibiotic Resistance Risk.

Pesticides promote the stable development of intensive global agriculture. Nevertheless, their residues in the soil can cause ecological and human health risks. Glyphosate is a popular herbicide and is generally thought to be ecologically safe and nontoxic, but this conclusion has been questioned. Herein, we investigated the interaction among soil fauna (Enchytraeus crypticus) exposed to glyphosate and found that glyphosate induced oxidative stress and detoxification responses in E. crypticus and disturbed their lipid metabolism and digestive systems. We further demonstrated that glyphosate disordered the gut microbiota of E. crypticus and increased the abundance of resistance determinants with significant human health risks. Empirical tests and structural equation models were then used to confirm that glyphosate could cause E. crypticus to generate reactive oxygen species, indirectly interfering with their gut microbiota. Our study provides important implications for deciphering the mechanisms of the ecotoxicity of pesticides under the challenge of worldwide pesticide contamination.

Anharmonic phonon renormalization and thermoelectric properties of CsPbX3 (X = Cl, Br, and I): first-principles calculations.

Halide perovskites with ultralow thermal conductivity have emerged as promising candidates for thermoelectric materials. We study the lattice dynamics and thermoelectric properties of cubic all-inorganic lead halide perovskites CsPbX3 (X = Cl, Br, and I) through first-principles calculations. Combined with self-consistent phonon theory, we have successfully renormalized the phonon frequency using a quartic anharmonic term, allowing us to accurately reproduce the phonon dispersion of the high-temperature cubic phase of CsPbX3 without any imaginary frequencies. Cubic CsPbX3 exhibit ultralow lattice thermal conductivities (0.61-1.71 Wm-1 K-1) at room temperature. Because of the strong quartic anharmonic renormalization and hardening of the soft modes, the lattice thermal conductivities of cubic CsPbX3 all exhibit weak temperature dependence. Notably, CsPbCl3 exhibits remarkably high thermal conductivity and a long phonon lifetime. This can be attributed to the smallest atomic mean square displacement and the weakest tilting and distortions of PbCl6 octahedra, resulting from the strongest Pb-Cl covalent bonding. Furthermore, the maximum ZT value of 0.63 at 900 K is obtained for the n-type CsPbBr3.

κ-Carrageenan Oligosaccharides Protect Nerves by Regulating Microglial Autophagy in Alzheimer's Disease.

κ-Carrageenan is a linear sulfated polysaccharide extracted from the cell wall of marine red algae, and its enzymatically digested oligosaccharides (KOS) can inhibit microglial hyperactivation. Alzheimer's disease (AD) is a common chronic neurodegenerative disease, characterized by cognitive and memory impairment accompanied by nerve cell damage. Microglia activation causing enhancement of proinflammatory effects and neurotoxicity is one of the early events in AD disease. In this study, whether KOS have therapeutic or preventive effects in the AD model prepared from APP/PS1 transgenic mice was determined. Learning and memory of AD mice were detected by water maze experiments, and microglial activation-related protein expression and deposition of APP and Aß1-42 in the brain were examined. The effects of KOS on expressed inflammatory factors and inflammation-related proteins by microglia were tested by cell experiments. Transwell coculture was used to investigate the effect of microglia on neural cell activity after KOS treatment. The results showed that KOS could relieve the clinical symptoms in AD mice, and a decrease in the expression of inflammatory factors and inflammation-related proteins in brain tissue was detected. KOS alleviated nerve cell apoptosis by inhibiting the overactivation of microglia, thus exhibiting neuroprotective effects. Exploring the protective effect of KOS inhibition of microglia inflammation is expected to provide a theoretical basis for KOS as a therapeutic drug for neurodegenerative diseases.

Ginseng-containing traditional medicine preparations in combination with fluoropyrimidine-based chemotherapy for advanced gastric cancer: A systematic review and meta-analysis.

BACKGROUND: Ginseng-containing traditional medicine preparations (G-TMPs) in combination with fluoropyrimidine-based chemotherapy (FBC) are well-known treatments for advanced gastric cancer (AGC), with a superior efficacy to FBC alone. However, evidence regarding their efficacy remains limited. The purpose of this meta-analysis is to evaluate the efficacy and safety of G-TMPs in combination with FBC for the treatment of AGC. METHODS: Eight electronic databases were searched for randomized controlled trials (RCTs) using G-TMPs with FBC for the treatment of AGC. The primary outcome included the tumor response, while the secondary outcomes included the quality of life (QoL), proportions of peripheral blood lymphocytes, adverse drug reactions (ADRs), and levels of cancer biomarkers. The quality of evidence for each outcome was assessed using GRADE profilers. RESULTS: A total of 1,960 participants were involved in the 26 RCTs included. Patients treated with FBC plus G-TMPs had better objective response (risk ratio [RR] = 1.23, 95% confidence interval [CI]: 1.13 to 1.35, p < 0.00001) and disease control (RR = 1.13, 95% CI: 1.08 to 1.19, p < 0.00001) rates than those treated with FBC alone. Additionally, the combination group had a better QoL, higher proportions of CD3+ T cells, CD4+ T cells, and natural killer cells, as well as a higher CD4+/CD8+ T-cell ratio. Furthermore, lower levels of CA19-9, CA72-4, and CEA were confirmed in the combination treatment group. In addition, G-TMPs reduced the incidence of ADRs during chemotherapy. CONCLUSION: In combination with FBC, G-TMPs can potentially enhance efficacy, reduce ADRs, and improve prognosis for patients with AGC. However, high-quality randomized studies remain warranted. SYSTEMATIC REVIEW REGISTRATION: PROSPERO Number: CRD42021264938.

Prediction of MAFLD and NAFLD using different screening indexes: A cross-sectional study in U.S. adults.

Introduction: Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as non-alcoholic fatty liver disease (NAFLD), has become the most common chronic liver disease worldwide. We aimed to explore the gender-related association between nine indexes (BMI/WC/VAI/LAP/WHtR/TyG/TyG-BMI/TyG-WC/TyG-WHtR) and MAFLD/NAFLD and examine their diagnostic utility for these conditions. Methods: Eligible participants were screened from the 2017-2018 cycle data of National Health and Nutrition Examination Survey (NHANES). Logistic regression and receiver operating characteristic (ROC) curve were used to assess the predictive performance of 9 indexes for MAFLD/NAFLD. Results: Among the 809 eligible individuals, 478 had MAFLD and 499 had NAFLD. After adjusting for gender, age, ethnicity, FIPR and education level, positive associations with the risk of MAFLD/NAFLD were found for all the nine indexes. For female, TyG-WHtR presented the best performance in identifying MAFLD/NAFLD, with AUC of 0.845 (95% CI = 0.806-0.879) and 0.831 (95% CI = 0.791-0.867) respectively. For male, TyG-WC presented the best performance in identifying MAFLD/NAFLD, with AUC of 0.900 (95% CI = 0.867-0.927) and 0.855 (95% CI = 0.817-0.888) respectively. Conclusion: BMI/WC/VAI/LAP/WHtR/TyG/TyG-BMI/TyG-WC/TyG-WHtR are important indexes to identify the risk of MAFLD and NAFLD.

Associations of serum multivitamin levels with the risk of non-alcoholic fatty liver disease: A population-based cross-sectional study in U.S. adults.

Vitamins were closely associated with non-alcoholic fatty liver disease (NAFLD) development, but no study had explored the association of serum multivitamin levels with NAFLD risk. We assessed the association between serum levels of both single-vitamin and multivitamins (VA, VB6, VB9, VB12, VC, VD, and VE) and the risk of NAFLD, using the database of National Health and Nutrition Examination Survey (NHANES) (cycles 2003-2004 and 2005-2006). We employed multivariable logistic regression and weighted quantile sum (WQS) regression models to explore the association of serum multivitamin levels with NAFLD. Among all 2,294 participants, 969 participants with NAFLD were more likely to be male, older, less educated, or have hypertension/high cholesterol/diabetes. After adjustment of covariates, serum VC/VD/VB6/VB9 levels were negatively correlated with NAFLD risk, while serum VA/VE levels were positively correlated with NAFLD risk. In the WQS model, elevated serum VA/VE levels and lowered serum VC/VD/VB6 levels were linearly associated with increased NAFLD risk. There was a non-linear relationship between serum VB9/VB12 levels and NAFLD risk. There were evident associations between serum multivitamin levels and reduced NAFLD risk, which was mainly driven by VD/VB9/VC. In conclusion, our findings suggested that serum multivitamin levels were significantly associated with the risk of NAFLD.

κ-Carrageenan Oligosaccharides Inhibit the Inflammation of Lipopolysaccharide-Activated Microglia Via TLR4/NF-κB and p38/JNK MAPKs Pathways.

Microglial inflammation plays an essential role in neurodegenerative disease. Our previous studies had shown that κ-carrageenan oligosaccharides (KOS) could inhibit the excessive activation of microglia that induced by LPS, while the interrelated mechanisms were still indistinct. Therefore, we detected the inflammatory signaling pathway on LPS-activated microglia that pretreat by different content of KOS to reveal the mechanism on KOS's inhibition of microglia inflammatory response. ELISA was used to detect the effects of KOS on the secretion of interleukin-1 (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and prostaglandin E2 (PG-2) by LPS-activated microglia, respectively. The production of reactive oxygen species (ROS) and nitric oxide (NO) in microglia cells was detected by flow cytometry, and the protein expression of immunoinflammation-related signaling pathways were detected by Western Blot. The results showed that KOS could significantly protected the microglia from the over-activated inflammatory by inhibiting the release of inflammatory cytokines and the oxidative stress response. And KOS could reduce the expression of the protein that related to the TLR4/NF-κB and p38/JNK MAPKs pathways activated by LPS in microglia. However, there may be no specific target of KOS in cells. Therefore, KOS, a natural algal source oligosaccharide, has immunomodulatory effects and can be used as a potential intervention therapy for inflammatory related neurodegenerative diseases.

κ-Carrageenan oligosaccharides induce microglia autophagy through AMPK/ULK1 pathway to regulate their immune response.

Microglia are the main effector cells of immune response in central nervous system and are important targets for disease prevention and treatment. Κ-carrageenan Oligosaccharide (KOS), obtained by enzymatic hydrolysis from carrageenan of marine red algae, can inhibit the release of inflammatory factors from the over-activated microglia. The mechanism of microglia autophagy induced by KOS and its relationship with inflammation were studied to explore the development prospect of KOS in the research and treatment of inflammatory related diseases. The effect of KOS on inducing autophagy was detected by the secretion of cytokines by lipopolysaccharide (LPS)-activated microglia, respectively. The protein expression of autophagy-related signaling pathways were detected by Western Blot. The results showed that KOS could significantly protect the microglia from over-activated inflammatory by inducing the autophagy and inhibiting the release of inflammatory cytokines. And KOS could reduce the expression of the protein that related to the AMPK/ULK1 pathways in microglia, so as to regulate the autophagy pathway, and inhibit the inflammatory response of over-activated microglia. The study on the effect of KOS on microglia autophagy and excessive inflammatory response will provide a theoretical basis for further studies on the inhibition of nerve injury by regulating microglia autophagy and inflammatory response.

YinQiSanHuang Jiedu decoction for the treatment of hepatitis B-related compensated liver cirrhosis: study protocol for a multi-center randomized controlled trial.

INTRODUCTION: Hepatitis B-related compensated liver cirrhosis is related to a higher risk of hepatocellular carcinoma, and antiviral therapy is the preferred method. As the pathological mechanisms of liver fibrosis are complex, drugs developed for a single target are difficult to be effective in clinical practice, so there are no chemical drugs or biological drugs with clear efficacy available for clinical application at present. Traditional Chinese medicine is a kind of medical science that has been gradually formed during thousands of years and continuously enriched by the people of all ethnic groups in China. Traditional Chinese medicine shows curative effects in the treatment of liver diseases, especially in the field of liver fibrosis prevention and treatment. This study aims to test the integrative medicine (Chinese medicine plus antiviral therapy) effective on lowing hepatocellular carcinoma risk among patients with hepatitis-related compensated liver cirrhosis. METHODS AND ANALYSIS: This is a multi-center randomized controlled trial, and a total of 5 hospitals and 802 patients will be involved in. All the subjects are randomly allocated to the YinQiSanHuang Jiedu decoction (YQSHD) group (n = 401) or the placebo group (n = 401). The YQSHD group receives YQSHD granule with entecavir (ETV), and the placebo group receives YQSHD placebo with ETV. The treatment period will last for 52 weeks, and the follow-up period for 52 ± 2 weeks. The primary outcome measure is the annual incidence of HCC. Outcomes will be assessed at baseline and after treatment. The objective of this trial is "the integrative of YQSHD with ETV reduce the annual incidence of HCC to 1%." ETHICS AND DISSEMINATION: The protocol has been approved by the Medical Ethics Committee of Guang'anmen Hospital, China (No.2019-006-KY), and the other centers in the trial will not begin recruiting until the local ethical approval has been obtained. Trial final results will be disseminated via publication. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900021532 . Registered on February 26, 2019.

Coronary Heart Disease and Depression or Anxiety: A Bibliometric Analysis.

This study aimed to conduct a bibliometric analysis of published studies on the association between coronary heart disease (CHD) and depression or anxiety. The study also aimed to identify leading authors, institutions, and countries to determine research hotspots and obtain some hints from the speculated future frontiers. Publications about CHD and depression or anxiety between 2004 and 2020 were collected from the Web of Science Core Collection (WOSCC) database. Bibliographic information, such as authorship, country, citation frequency, and interactive visualization, was generated using VOSviewer1.6.16 and CiteSpace5.6.R5. In total, 8,073 articles were identified in the WOSCC database. The United States (2,953 publications), Duke University and Harvard University (214 publications), Psychosomatic Medicine (297 publications), and Denollet Johan. (99 publications) were the most productive country, institutions, journal, and author, respectively. The three hotspots of the research were "The relationship between depression and CHD," "depression and myocardial infarction," and "The characteristic of women suffering depression after MI." The four future research frontiers are predicted to be "treating depression in CHD patients with multimorbidity," "psychometric properties of instruments for assessing depression and anxiety in CHD patients," "depression or anxiety in post-PCI patients," and "other mental diseases in CHD patients." Bibliometric analysis of the association between CHD and depressive disorders might identify new directions for future research.

Autophagy is essential for the endothelial differentiation of breast cancer stem­like cells.

Blood vessels serve an important role in tumor growth and metastasis, and recent studies have shown that certain tumor cancer stem cells may differentiate into endothelial cells and contribute to angiogenesis. In the present study, vascular endothelial growth factor (VEGF) was used to induce endothelial differentiation of breast cancer stem­like cells (BCSLCs), and methods including flow cytometry, western blotting and immunofluorescence were used to study the relationship between autophagy and the endothelial differentiation of BCSLCs. The results showed that BCSLCs could differentiate into endothelial cells under the induction of VEGF in vitro. Subsequently, the role of autophagy in the endothelial differentiation of BCSLCs was examined. Autophagic activity was measured during endothelial differentiation of BCSLCs, and the association between autophagy and endothelial differentiation was investigated using autophagy activators, autophagy inhibitors and autophagy related 5 (Atg5)­knockdown BCSLCs. Autophagy was increased during endothelial differentiation of BCSLCs, and there was a positive association between autophagy and endothelial differentiation. The ability of cells to undergo endothelial differentiation was reduced in BCSLCs with Atg5 knockdown. Therefore, autophagy was essential for endothelial differentiation of BCSLCs, and the findings of the present study may highlight novel potential avenues for reducing angiogenesis and improving treatment of breast cancer.

Efficacy of chitosan and sodium alginate scaffolds for repair of spinal cord injury in rats.

Spinal cord injury results in the loss of motor and sensory pathways and spontaneous regeneration of adult mammalian spinal cord neurons is limited. Chitosan and sodium alginate have good biocompatibility, biodegradability, and are suitable to assist the recovery of damaged tissues, such as skin, bone and nerve. Chitosan scaffolds, sodium alginate scaffolds and chitosan-sodium alginate scaffolds were separately transplanted into rats with spinal cord hemisection. Basso-Beattie-Bresnahan locomotor rating scale scores and electrophysiological results showed that chitosan scaffolds promoted recovery of locomotor capacity and nerve transduction of the experimental rats. Sixty days after surgery, chitosan scaffolds retained the original shape of the spinal cord. Compared with sodium alginate scaffolds- and chitosan-sodium alginate scaffolds-transplanted rats, more neurofilament-H-immunoreactive cells (regenerating nerve fibers) and less glial fibrillary acidic protein-immunoreactive cells (astrocytic scar tissue) were observed at the injury site of experimental rats in chitosan scaffold-transplanted rats. Due to the fast degradation rate of sodium alginate, sodium alginate scaffolds and composite material scaffolds did not have a supporting and bridging effect on the damaged tissue. Above all, compared with sodium alginate and composite material scaffolds, chitosan had better biocompatibility, could promote the regeneration of nerve fibers and prevent the formation of scar tissue, and as such, is more suitable to help the repair of spinal cord injury.

Cloning, identification and characterization of a novel κ-carrageenase from marine bacterium Cellulophaga lytica strain N5-2.

A novel κ-carrageenase gene (Cly-κ-car) was cloned and heterologously expressed from marine bacterium Cellulophaga lytica strain N5-2. The gene comprised an open reading frame of 1488bp encoding 495 amino acid residues. The deduced protein had a calculated molecular weight of 55.24kDa with an estimated isoelectric point of 9.90. Multiple alignment analysis revealed that Cly-κ-CAR shared identity with κ-carrageenases from Zobellia sp. M-2 (46%), Zobellia galactanivorans (42%) and Rhodopirellula islandica (38%). Recombinant Cly-κ-CAR (R-Cly-κ-CAR) had maximum specific activity of 620.08U/mg at 35°C, pH 7.0, 0.7% κ-carrageenan and in the presence of 0.6% NaCl. It retained >75% of its initial activity after heat treatment below 35°C for 2h. More than 50% of its activity was maintained after incubation at pH 5.0-8.0 and 4°C for 6h. The Km and Vmax values for κ-carrageenan were 0.94mg/ml and 13.42mM/min/mg, respectively. Thin layer chromatographic analysis of the R-Cly-κ-CAR hydrolysis products revealed that the enzyme hydrolyzed κ-carrageenan into neo-κ-carraoctaose and neo-κ-carrahexaose. R-Cly-κ-CAR is a novel κ-carrageenase enzyme and could be a valuable tool to produce high degree of polymerization κ-carrageenan oligosaccharides with various biological activities.

Immunomodulatory function of κ-carrageenan oligosaccharides acting on LPS-activated microglial cells.

The major neurodegenerative diseases are characterized by increasing of activated-microglial cells and inflammatory cytokines in the central nervous system. Carrageenan extracted from red algae is a kind of polysaccharide with sulfate groups. The oligosaccharides were obtained from carrageenan by enzymatic degradation. To detect the immunomodulatory activity of κ-carrageenan oligosaccharides (KOS) on microglial cells and the relationship to the sulfate group content, the desulfated derivatives of KOS (DSK) were obtained by dimethyl sulfoxide-methanol-pyridine method. KOS was labeled with fluorescein isothiocyanate. The effect of KOS and DSK on lipopolysaccharide (LPS)-activated microglial cells was detected. Hematoxylin-eosin staining and flow cytometric were used to detect the cell viability. The "scratch" migration assay, ornithine analysis and RT-PCR were used to determine the cell migration, arginase and TNF-α released by microglial cells, respectively. The effect of LPS and KOS on microglial cells was determined by flow cytometry and laser scanning confocal microscopy. The results showed that KOS and DSK could inhibit the cell viability, arginase and TNF-α released by LPS-activated microglia cell with concentration dependent manner. But the effect of DSK was weaker than that of KOS. KOS aggregated on the cell surface firstly, and then they enter into the cell to the nucleus, spread over the entire cell finally. But the exist of LPS could prevent the entrance of KOS. It could be concluded that KOS could protect microglial cells from being activated by LPS, and its inhibition function had relationship to the sulfate group content of KOS, while there were competition between LPS and KOS.

Enzymatic preparation of κ-carrageenan oligosaccharides and their anti-angiogenic activity.

The mixture of κ-neocarrabiose-sulfate, κ-neocarrahexaose-sulfate and κ-neocarraoctaose-sulfate were prepared from κ-carrageenan with enzyme. The anti-tumor and anti-angiogenic activity of obtained κ-carrageenan oligosaccharides (KOS), were explored. The results showed that KOS could inhibit the proliferation, migration and tube formation of ECV304 cells, and could inhibit the growth of new vessels in CAM model. KOS displayed strong anti-tumor activity in both S180 and MCF-7 xenograft models. Only human CD105 was detected in MCF-7 xenograft tumor, moreover KOS could decrease the growing of new blood vessels derived from tumor cell. Real-time PCR results showed that KOS could suppress the mRNA expression of human VEGF, bFGF, bFGFR and CD105 in MCF-7 xenograft tumor. All these results indicated that KOS has anti-tumor and anti-angiogenic activity in vivo and in vitro. Especially K has the potency to inhibit the differentiation of tumor cell to blood vessel endothelial cell.

Characterization of a κ-carrageenase from marine Cellulophaga lytica strain N5-2 and analysis of its degradation products.

A carrageenan-degrading marine Cellulophaga lytica strain N5-2 was isolated from the sediment of carrageenan production base. A κ-carrageenase (EC 3.2.1.83) with high activity was purified to electrophoretic homogeneity from the culture supernatant by a procedure of ammonium sulfate precipitation, dialyzing and gel filtration on SephadexG-200 and SephadexG-75. The purified enzyme was verified as a single protein on SDS-PAGE, and whose molecular weight was 40.8 kDa. The κ-carrageenase yielded a high activity of 1170 U/mg protein. For κ-carrageenase activity, the optimum temperature and pH were 35 °C and pH 7.0, respectively. The enzyme was stable at 40 °C for at least 2.5 h. The enzyme against κ-carrageenan gave a Km value of 1.647 mg/mL and a Vmax value of 8.7 µmol/min/mg when the reaction was carried out at 35 °C and pH 7.0. The degradation products of the k-carrageenase were analyzed by thin layer chromatography (TLC), high performance liquid chromatography (HPLC), electrospray ionization time-of-flight mass spectroscopy (ESI-TOF-MS) and 13C-NMR spectroscopy, and the results indicated that the enzyme was specific of the ß-1,4 linkage and hydrolyzed κ-carrageenan into κ-neocarraoctaose-sulfate and κ-neocarrahexaose-sulfate first, and then broke κ-neocarraoctaose-sulfate into κ-neocarrabiose-sulfate and κ-neocarrahexaose-sulfate.

The immune regulation of κ-carrageenan oligosaccharide and its desulfated derivatives on LPS-activated microglial cells.

Neurodegenerative disease involves an inflammatory response in the central nervous system characterized by an increase in inflammatory cytokines and activation of microglial cell. To reveal the immune regulation activity of κ-carrageenan oligosaccharides (KOS) on microglia cell activated by LPS and the relationship between the sulfate group content of KOS and its immune regulation activity, KOS was prepared by enzymatic hydrolysis. The degradation products of κ-carrageenan were analyzed by high performance liquid chromatography (HPLC), ESI-TOF-MS and (13)C NMR spectroscopy, and the results indicated that the hydrolyzed products of the κ-carrageenase were κ-neocarrabiose-sulfate, κ-neocarrahexaose-sulfate and κ-neocarraoctaose-sulfate, respectively. Then desulfated derivatives of KOS (DSK) were obtained with DMSO-methanol-pyridine method. The effect of KOS and DSK on the viability of microglia cell activated by LPS was determined with MTT method. Griess assay and ELISA method were used to determine the contents of NO/NO(2-), TNF-α and IL-10 released by activated microglia cell, respectively. The results showed that KOS could inhibit the viability and content of NO, TNF-α and IL-10 released by LPS-activated microglia cell dose dependently. Compared with that of KOS, the inhibiting activity of DSK is weaker. So it could be concluded that KOS could protect microglial cell from being activated by LPS, and there was a positive relationship between the sulfate group content of KOS and its protection function.