The major histocompatibility complex participates in Parkinson's disease.

Parkinson's disease (PD) is a common neurodegenerative disease characterized by progressive loss of dopaminergic neurons in the substantia nigra and the aggregation of alpha-synuclein (α-syn). The central nervous system (CNS) has previously been considered as an immune-privileged area. However, studies have shown that the immune responses are involved in PD. The major histocompatibility complex (MHC) presents antigens from antigen-presenting cells (APCs) to T lymphocytes, immune responses will be induced. MHCs are expressed in microglia, astrocytes, and dopaminergic neurons. Single nucleotide polymorphisms in MHC are related to the risk of PD. The aggregated α-syn triggers the expression of MHCs by activating glia cells. CD4+ and CD8+ T lymphocytes responses and microglia activation are detected in brains of PD patients. In addiction immune responses further increase blood-brain barrier (BBB) permeability and T cell infiltration in PD. Thus, MHCs are involved in PD through participating in immune and inflammatory responses.

Administration of Gracilariopsis lemaneiformis polysaccharide attenuates cisplatin-induced inflammation and intestinal mucosal damage in colon-26 carcinoma tumor-bearing mice.

BACKGROUND: Our preliminary research revealed that the polysaccharide GP90 from Gracilariopsis lemaneiformis enhanced the antitumor effect of cisplatin, indicating that GP90 may increase the chemotherapeutic sensitivity. However, it is still necessary to fully understand whether GP90 can also improve the intestinal barrier dysfunction and systemic inflammation induced by cisplatin. RESULTS: GP90 has been demonstrated to inhibit the excessive release of nitirc oxide, interleukin (IL)-6, IL-1ß and tumor necrosis factor (TNF)-α induced by lipopolysaccharide in RAW264.7 cells. In vivo, GP90 effectively ameliorated the decrease in the serum CD4+ /CD8+ T-cell ratio induced by cisplatin and significantly reduced the increase in the inflammatory cytokines, CD4+ Foxp3+ , CD4+ granzyme B+ and CD4+ TNF-α induced by cisplatin. Furthermore, when combined with cisplatin, GP90 increases the protein expression levels of mucin-2 and zonula occludens-1 in the mouse small intestine. Additionally, GP90 combined with cisplatin has a modulatory effect on the intestinal microbiota by elevating the Firmicutes-to-Bacteroidetes ratio and the relative abundance of beneficial microorganisms (Lachnospiraceae bacterium), at the same time as reducing the abundance of cisplatin specific Bacteroides acidifaciens and elevating the content of butyric acid and isobutyric acid. CONCLUSION: Collectively, these findings indicate that GP90 potentially mitigates inflammation and protects the intestinal barrier in tumor-bearing organisms undergoing chemotherapy. © 2024 Society of Chemical Industry.

Recycling of waste aluminum scraps to fabricate sulfidated zero-valent iron-aluminum particles for enhanced chromate removal.

Massive waste aluminum scraps produced from the spent aluminum products have high electron capacity and can be recycled as an attractive alternative to materials based on zero-valent iron (Fe0) for the removal of oxidative contaminants from wastewater. This study thus proposed an approach to fabricate micron-sized sulfidated zero-valent iron-aluminum particles (S-Al0@Fe0) with high reactivity, electron selectivity and capacity using recycled waste aluminum scraps. S-Al0@Fe0 with a three-layer structure contained zero-valent aluminum (Al0) core, Fe0 middle layer and iron sulfide (FeS) shell. The rates of chromate (Cr(VI)) removal by S-Al0@Fe0 at pH 5.0‒9.0 were 1.6‒5.9 times greater than that by sulfidated zero-valent iron (S-Fe0). The Cr(VI) removal capacity of S-Al0@Fe0 was 8.2-, 11.3- and 46.9-fold greater than those of S-Fe0, zero-valent iron-aluminum (Al0-Fe0) and Fe0, respectively. The chemical cost of S-Al0@Fe0 for the equivalent Cr(VI) removal was 78.5% lower than that of S-Fe0. Negligible release of soluble aluminum during the Cr(VI) removal was observed. The significant enhancement in the reactivity and capacity of S-Al0@Fe0 was partially ascribed to the higher reactivity and electron density of the Al0 core than Fe0. More importantly, S-Al0@Fe0 served as an electric cell to harness the persistent and selective electron transfer from the Al0-Fe0 core to Cr(VI) at the surface via coupling Fe0-Fe2+-Fe3+ redox cycles, resulting in a higher electron utilization efficiency. Therefore, S-Al0@Fe0 fabricated using recycled waste aluminum scraps can be a cost-effective and environmentally-friendly alternative to S-Fe0 for the enhanced removal of oxidative contaminants in industrial wastewater.

Tuna trimmings (Thunnas albacares) hydrolysate alleviates immune stress and intestinal mucosal injury during chemotherapy on mice and identification of potentially active peptides.

In this study, Tuna trimmings (Thunnas albacares) protein hydrolysate (TPA) was produced by alcalase. The anti-tumor synergistic effect and intestinal mucosa protective effect of TPA on S180 tumor-bearing mice treated with 5-fluorouracil (5-FU) chemotherapy were investigated. The results showed that TPA can enhance the anti-tumor effect of 5-FU chemotherapy, as evident by a significant reduction in tumor volume observed in the medium and high dose TPA+5-FU groups compared to the 5-FU group (p < 0.001). Moreover, TPA significantly elevated the content of total protein and albumin in all TPA dose groups (p < 0.01, p < 0.001), indicating its ability to regulate the nutritional status of the mice. Furthermore, histopathological studies revealed a significant increase in the height of small intestinal villi, crypt depth, mucosal thickness, and villi area in the TPA+5-FU groups compared to the 5-FU group (p < 0.05), suggesting that TPA has a protective effect on the intestinal mucosa. Amino acid analysis revealed that TPA had a total amino acid content of 66.30 g/100 g, with essential amino acids accounting for 30.36 g/100 g. Peptide molecular weight distribution analysis of TPA indicated that peptides ranging from 0.25 to 1 kDa constituted 64.54%. LC-MS/MS analysis identified 109 peptide sequences, which were predicted to possess anti-cancer and anti-inflammatory activities through database prediction. Therefore, TPA has the potential to enhance the antitumor effects of 5-FU, mitigate immune depression and intestinal mucosal damage induced by 5-FU. Thus, TPA could be serve as an adjuvant nutritional support for malnourished patients undergoing chemotherapy.

Structural characterization of a sulfated polysaccharide from Gracilariopsis lemaneiformis and its potentiation of cisplatin antitumor activity in Colon-26 carcinoma tumor-bearing mice by inducing ferroptosis.

Ferroptosis, a form of regulated cell death caused by iron-mediated lipid peroxidation, has become a potential strategy to overcome drug resistance and improve the efficacy of traditional cancer treatments. In this study, we investigated whether treatment with the combination of Gracilariopsis lemaneiformis polysaccharides and cisplatin (CP) potentiated the antitumor activity in a Colon-26 carcinoma tumor-bearing mouse model by ferroptosis activation. The G. lemaneiformis polysaccharide GP90 was mainly composed of (1→3) linked 4-O-sulfate-ß-D-galactose and (1→4) linked 3,6-anhydro-α-L-galactose with a molecular weight of 12.45 kDa. Compared with the CP group, the combination of GP90 and CP significantly suppressed tumor growth. Based on the transcriptomic and metabolomic analyses of tumor tissue, GP90 enhanced the antitumor effect of CP by promoting ferroptosis and regulating ferroptosis-related metabolic pathways. Moreover, the accumulation of 4-hydroxy-2-nonenal (4-HNE) and down-regulation of the expression of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (Gpx4) were verified by immunohistochemistry staining. Finally, gene set enrichment analysis showed that positive immunoregulatory pathways were significantly enriched in the GP90 and CP combination group. Our results indicate that GP90 potentiates chemotherapy sensitivity by targeting the transferrin receptor and SLC7A11/Gpx4 pathway to induce ferroptosis, which might be a useful therapeutic target in colorectal cancer patients.

Antidiabetic effects of protein hydrolysates from Trachinotus ovatus and identification and screening of peptides with α-amylase and DPP-IV inhibitory activities.

In the present study, the antidiabetic properties of Trachinotus ovatus protein hydrolysates (TOH) in streptozotocin-induced diabetic mice were investigated, and peptides with α-amylase (AAM) and dipeptidyl peptidase IV (DPP-IV) inhibitory activities were identified and screened. The results showed that TOH alleviated body weight loss, polyphagia, blood glucose elevation and insulin secretion decline in diabetic mice. After 4 weeks of TOH administration, random blood glucose (RBG) decreased significantly. The TOH groups showed a dose-dependent reduction in fasting blood glucose (FBG), especially in the high-dose TOH group, which reduced FBG by 58% versus the effect of metformin. Moreover, TOH exerted a remarkable protective effect on hepatorenal function, as evidenced by increased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) and decreased serum urea levels. Histopathological studies confirmed that TOH can significantly protect the kidney and pancreas from histological changes, which was of great benefit for ensuring the normal secretion of insulin and preventing the occurrence of complications such as diabetic nephropathy. Two fractions with higher inhibitory activity against AAM and DPP-IV, F4 and F6, were obtained from the ultrafiltration of TOH-2 (≤3 kDa). A total of 19 potentially active peptides from F4 and 3 potentially active peptides from F6 were screened by LC‒MS/MS combined with bioinformatic analysis. These peptides are small molecular peptides composed of 2-6 amino acids, rich in characteristic amino acids such as proline, arginine, phenylalanine and asparagine, and contain high proportions of peptides (68% for F4, 67% for F6) with hydrophobicity ≥50%. They offer potent antidiabetic potential and could potentially bind to the active sites in the internal cavities of the target enzymes AAM and DPP-IV. In summary, this study revealed for the first time the antidiabetic effects of protein hydrolysates of Trachinotus ovatus and their derived peptides, which are promising natural ingredients with the potential to be used for the treatment or prevention of diabetes.

Octopus-derived antioxidant peptide protects against hydrogen peroxide-induced oxidative stress in IEC-6 cells.

This study aims to find antioxidant peptides from octopus protein hydrolyzates and verify the protective effects against H2O2-induced oxidative stress in IEC-6 cells. After the alcalase hydrolysate was ultrafiltrated, purified by Sephadex G-25 gel fractionation and semipreparative reversed-phase high-performance liquid chromatography (RP-HPLC), 16 peptides were identified, and chemically synthesized. In particular, the peptides AQNY, AMMLAW, FEGAW, GGAW, VDTVVCVW, and VVCLW showed better oxygen radical absorbance capacity (ORAC) and ABTS radical scavenging capacity. Among them, the smallest-molecular-weight peptide GGAW exhibited the best antioxidant activity. Furthermore, GGAW protected IEC-6 cells from H2O2-induced oxidative damage by significantly reducing the generation of reactive oxygen species (ROS), malondialdehyde (MDA), and lactate dehydrogenase (LDH), and increasing the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), thereby improving cell viability. These results indicated that the peptide GGAW possessed the antioxidant capacity to prevent oxidative stress damage.

Purification and Identification of Novel Myeloperoxidase Inhibitory Antioxidant Peptides from Tuna (Thunnas albacares) Protein Hydrolysates.

Antioxidative peptides that inhibit myeloperoxidase (MPO) enzyme activity can effectively defend against oxidative stress damage. The antioxidant peptides from tuna protein were produced using alcalase hydrolysis and purified by ultrafiltration and Sephadex G-15, and the fractions with the highest free radicals scavenging ability and oxygen radical absorbance capacity (ORAC) values were sequenced using HPLC-MS/MS. Fifty-five peptide sequences were identified, 53 of which were successfully docked into MPO. The representative peptide ACGSDGK had better antioxidant activity and inhibition of MPO chlorination and peroxidation than the reference peptide hLF1-11. The docking model further showed intense molecular interactions between ACGSDGK and MPO, including hydrogen bonds, charge, and salt bridge interactions, which occluded the active site and blocked the catalytic activity of MPO. These results suggested that the antioxidant peptide ACGSDGK has the potential to inhibit oxidative stress and alleviate inflammation in vivo because of its inhibitory effect on the MPO enzyme.

Human Umbilical Mesenchymal Stem Cell Xenografts Repair UV-Induced Photokeratitis in a Rat Model.

Most patients with a corneal injury are administered anti-inflammatory medications and antibiotics, but no other treatments are currently available. Thus, the corneal injury healing is unsatisfactory, affects the vision, and has a risk of blindness in severe cases. Human umbilical mesenchymal stem cells exhibit pluripotent and anti-inflammatory properties and do not cause immunological rejection in the host. Rats were irradiated with type B ultraviolet (UVB) light to generate a stable animal model of photokeratitis. After irradiation-induced photokeratitis, human umbilical mesenchymal stem cells were implanted into the subconjunctival space of the lateral sclera, and the changes in the corneal pathology were evaluated. Three weeks after implantation, many mesenchymal stem cells were visible in the subconjunctival space. These mesenchymal stem cells effectively reduced the extent of injury to the adjacent corneal tissue. They accelerated the epithelial layer repair, reduced the inflammatory response and neovascularization, and improved the disorganization of collagen and fibronectin in the corneal stroma caused by the injury. In conclusion, xenografted human umbilical mesenchymal stem cells can survive in rat eye tissues for a long time, effectively support the structural integrity of injured corneal tissues, restore corneal permeability, and reduce abnormal neovascularization. This study provides a new approach to the treatment of photokeratitis.

[Evaluation of brain injury caused by stick type blunt instruments based on convolutional neural network and finite element method].

The finite element method is a new method to study the mechanism of brain injury caused by blunt instruments. But it is not easy to be applied because of its technology barrier of time-consuming and strong professionalism. In this study, a rapid and quantitative evaluation method was investigated to analyze the craniocerebral injury induced by blunt sticks based on convolutional neural network and finite element method. The velocity curve of stick struck and the maximum principal strain of brain tissue (cerebrum, corpus callosum, cerebellum and brainstem) from the finite element simulation were used as the input and output parameters of the convolutional neural network The convolutional neural network was trained and optimized by using the 10-fold cross-validation method. The Mean Absolute Error (MAE), Mean Square Error (MSE), and Goodness of Fit ( R 2) of the finally selected convolutional neural network model for the prediction of the maximum principal strain of the cerebrum were 0.084, 0.014, and 0.92, respectively. The predicted results of the maximum principal strain of the corpus callosum were 0.062, 0.007, 0.90, respectively. The predicted results of the maximum principal strain of the cerebellum and brainstem were 0.075, 0.011, and 0.94, respectively. These results show that the research and development of the deep convolutional neural network can quickly and accurately assess the local brain injury caused by the sticks blow, and have important application value for understanding the quantitative evaluation and the brain injury caused by the sticks struck. At the same time, this technology improves the computational efficiency and can provide a basis reference for transforming the current acceleration-based brain injury research into a focus on local brain injury research.

Structural characterization, and in vitro immunostimulatory and antitumor activity of an acid polysaccharide from Spirulina platensis.

In this study, a novel heteropolysaccharide named SP90-1 with immunostimulatory and antitumor activity was purified and characterized from Spirulina platensis. SP90-1 has a molecular weight of 63.92 kDa and mainly consists of rhamnose (Rha), glucose (Glc), galactose (Gal) and glucuronic acid (GlcA), followed by the minor components Fuc and Xyl. The backbone of SP90-1 was determined to be →2)-α-d-Rhap-(1 â†’ 2,3)-α-d-Rhap-(1 â†’ 4)-ß-d-Glcp-(1 â†’ [3)-ß-d-Rhap-(1→]3, with branches at the O-3 of Rha, consisting of the side chains 4-Galp and 4-GlcpA. SP90-1 was found to significantly enhance phagocytic capacity, promote the secretion of nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) in RAW264.7 cells, and remarkably inhibit the growth of A549 lung cancer cells. These findings demonstrate that SP90-1 could potentially be further explored for immunomodulatory biomedical applications.

Strike Velocity Prediction of Stick Blunt Instruments Based on Backpropagation Neural Network.

OBJECTIVES: To analyze and predict the striking velocity range of stick blunt instruments in different populations, and to provide basic data for the biomechanical analysis of blunt force injuries in forensic identification. METHODS: Based on the Photron FASTCAM SA3 high-speed camera, Photron FASTCAM Viewer 4.0 and SPSS 26.0 software, the tester's maximum striking velocity of stick blunt instruments and related factors were calculated and analyzed, and inputed to the backpropagation (BP) neural network for training. The trained and verified BP neural network was used as the prediction model. RESULTS: A total of 180 cases were tested and 470 pieces of data were measured. The maximum striking velocity range was 11.30-35.99 m/s. Among them, there were 122 female data, the maximum striking velocity range was 11.63-29.14 m/s; there were 348 male data, the maximum striking velocity range was 20.11-35.99 m/s. The maximum striking velocity of stick blunt instruments increased with the increase of weight and height, but there was no obvious increase trend in the male group; the maximum striking velocity decreased with age, but there was no obvious downward trend in the female group. The maximum striking velocity of stick blunt instruments has no significant correlation with the material and strike posture. The root mean square error (RMSE), the mean absolute error (MAE) and the coefficient of determination (R2) of the prediction results by using BP neural network were 2.16, 1.63 and 0.92, respectively. CONCLUSIONS: The prediction model of BP neural network can meet the demand of predicting the maximum striking velocity of different populations.

Correlation of serum ferritin levels with neurological function-related indices and cognitive dysfunction in patients with cerebral hemorrhage.

AIMS: The purpose of this study was to explore the correlation of serum ferritin (FS) levels with neurological function-related indices, such as neuron-specific enolase (NSE) and S100ß protein levels, and cognitive dysfunction in patients with cerebral hemorrhage. MATERIALS AND METHODS: Patients with acute non-traumatic cerebral hemorrhage (cerebrovascular disease (VD), n = 128) and healthy controls (CON, n = 128) were included. FS, NSE, and S100ß levels were measured using ELISA. Cognitive functions were evaluated using the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE). The receiver operating characteristic (ROC) curve was used to assess the ability of SE, NSE, and serum S100ß to predict the diagnosis of cognitive dysfunction in patients with cerebral hemorrhage. Multivariate logistic regression analysis was used to assess the risk factors of cognitive impairment in patients with cerebral hemorrhage. RESULTS: Cognitive impairment in patients with VD was closely related to the increased levels of SE, NSE, and S100ß. There was a strong correlation between MoCA and MMSE scores and the levels of FS, NSE, and S100ß. The independent risk factors leading to cognitive impairment in cerebral hemorrhage mainly include family history of cerebrovascular disease, body mass index, hypertension, smoking frequency, and elevated levels of low-density lipoproteins, NSE, FS, and S100ß. CONCLUSION: NSE, FS, and S100ß can be used as important markers for the diagnosis of cognitive impairment in patients with cerebral hemorrhage.

The Effect of 3D Printing Metal Materials on Osteoporosis Treatment.

3D printing has been in use for a long time and has continued to contribute to breakthroughs in the fields of clinical, physical, and rehabilitation medicine. In order to evaluate the role of 3D printing technology in treating spinal disorders, this paper presents a systematic review of the relevant literature. 3D printing is described in terms of its adjunctive function in various stages of spinal surgery and assistance in osteoporosis treatment. A review of metal 3D printed materials and applications of the technology is also provided.

Oyster polysaccharides ameliorate intestinal mucositis and improve metabolism in 5-fluorouracil-treated S180 tumour-bearing mice.

The purpose of this study was to investigated the potential role of gut microbiota in protecting the intestinal barrier and improving nutritional metabolism in 5-FU-treated S180 tumour-bearing mice after treatment with oyster polysaccharide (CHP). CHP, with an α-(1→4) d-linked glucose backbone and (→4,6)-α-d-Glc-(1→) branches every 4.7 residues on average, increased the villus height, crypt depth, mucosa thickness, villus surface area and V/C ratio; decreased the expression of IL-1ß, IL-6, and TNF-α; and even restored the TP, ALB, PA, TRF, IgA, IgM and IgG levels to normal levels. All these factors are related to CHP increasing the propionic acid- and butyric acid-producing microorganisms and decreasing the production of Bacteroides, Prevotellaceae_UCG-001 and Rikenellaceae_RC9_gut_group, thus affecting the TLRs signalling pathway. In conclusion, CHP attenuates 5-FU-induced intestinal mucositis and malnutrition by regulating gut microbiota, and can improve the prognosis of patients receiving chemotherapy.

Identification of octopus peptide and its promotion of ß-casein synthesis in a mouse mammary epithelial cell line.

Octopus protein hydrolysate has been reported to increase milk yield and milk protein production. In this paper, the utilization and underlying mechanisms of bioactive peptide fractions from octopus protein hydrolysate on ß-casein expression in mouse mammary epithelial cells (HC11) were investigated. Fraction OPH3-1 significantly stimulated cell proliferation and ß-casein synthesis in HC11 cells, which was purified by ultra-filtration and gel-filtration chromatography. The MWs of the peptides from OPH3-1 ranged from 525-2,578 Da and consisted of 7-26 amino acid residues. Most of the peptides demonstrated the typical characteristics of milk protein synthesis promotion, especially MGLAGPR, MGDVLNF, EAPLMHV, and TEAPLMHV. Additionally, the mRNA abundances of mTOR, S6K1, 4EBP1, JAK2, and STAT5 were significantly enhanced by OPH3-1, which was consistent with the increased ß-casein expression. These results suggest that the OPH3-1 peptides can promote the proliferation of mammary epithelial cells and increase ß-casein synthesis. PRACTICAL APPLICATIONS: Breastfeeding mothers are generally recommended to take octopus soup as a daily diet to promote lactation. The peptides fraction OPH3-1 from the enzymatic hydrolysate of Octopus vulgaris which was revealed to significantly stimulate mammary epithelial cell proliferation and ß-casein synthesis was obtained. This study suggests that octopus peptides can be used as nutritional supplements to increase the quantity and quality of milk production.

Application of Magnetic Resonance Imaging Molecular Probe in the Study of Pluripotent Stem Cell-Derived Neural Stem Cells for the Treatment of Posttraumatic Paralysis of Cerebral Infarction.

The feasibility and efficacy of magnetic resonance imaging molecular probe application and pluripotent stem cell-derived neural stem cell (NSC) transplantation for the treatment of hind limb paralysis in mice with cerebral infarction were studied. A model of middle cerebral artery infarction using adult mice was established to stimulate hind limb reactions. After the model was successfully established, the mice were first divided into an experimental group and a control group, with 25 mice in each group. Cultured neural cells were obtained from the cerebral cortex and hippocampus of a mouse 15 days pregnant to prepare pluripotent stem cells. Pluripotent stem cell-derived NSCs were identified by positive expression of Nestin. The experimental group was injected with 1 µL of NSC suspension through the tail vein, and the control group was injected with 1 µL of saline through the tail vein. The neurologic function of mice in each group was scored 1 day, 3 days, 7 days, 14 days, and 28 days after transplantation according to the Garcia 18 subscale. Finally, the differentiation, migration, and integration of pluripotent stem cell-derived NSCs after transplantation were observed using a magnetic resonance imaging molecular probe method. The results showed that the neurologic function scores of the ischemic transplantation group were significantly higher than those of the control group, and the results were significantly different (P < 0.05). Through research, it was found that after transplantation of pluripotent stem cell-derived NSCs, the transplanted cells migrated and differentiated around the body at 28 days and participated in angiogenesis, and the blood vessels in the infarcted area were obviously proliferated. The NSCs cultured in vitro were transplanted to the small infarction after cerebral infarction. In rats, it plays a positive role in the repair of nerve function in mice with cerebral infarction. NSCs cultured in vitro can survive, migrate, and differentiate in the brain tissue of mouse ischemic models and play a positive role in the repair of neurologic function in mice with cerebral infarction. Magnetic resonance imaging molecular probes have a good adjuvant effect on the use of pluripotent stem cell-derived NSCs to treat hind limb paralysis in mice with cerebral infarction.

Hypolipidemic effects of protein hydrolysates from Trachinotus ovatus and identification of peptides implied in bile acid-binding activity using LC-ESI-Q-TOF-MS/MS.

In the present work, analysis of the hypolipidemic properties of Trachinotus ovatus protein hydrolysates (TOPHs) and identification of peptides with bile acid-binding activity were performed. Hydrolysates prepared by trypsin digestion exhibited the highest in vitro bile acid-binding capacities compared with hydrolysates prepared with the other four proteases and were mainly composed of small peptides and amino acids with molecular weights <3 kDa, accounting for 77.30%. Among the five ultra-filtration fractions of TOPHs, TOPHs-5 (<3 kDa) exhibited the highest in vitro bile acid-binding capacity, which was equivalent to 77.97% of cholestyramine at the same concentration. A total of 68 peptides were identified from TOPHs-5 by LC-ESI-Q-TOF-MS/MS and 9 of them had hydrophobicity of more than 60%. These highly hydrophobic peptides might be associated with the bile acid-binding activity of TOPHs-5. In vivo experiments indicated that the TOPHs could effectively reduce total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and the atherogenic index (AI), while they could evidently increase the high-density lipoprotein cholesterol (HDL-C) content. Furthermore, TOPHs exerted a marked protective effect on hepatorenal function, as evidenced by decreased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatinine (CREA). Histopathological studies confirmed that TOPHs evidently protected the liver from histological alterations. In summary, for the first time, hypolipidemic effects and subsequential identification were obtained from TOPHs, which are promising natural ingredients that could potentially be employed in the management of hyperlipidemia.

Composition characterization of oyster polysaccharides from Crassostrea hongkongensis and their protective effect against H2O2-induced oxidative damage in IEC-6 cells.

The proliferative activity of oyster polysaccharides in intestine epithelial cells (IEC-6) alleviated 5-fluorouracil-induced intestinal inflammation. In this study, we aimed to measure the ability of oyster polysaccharides to promote IEC-6 cell migration and antioxidant activity and further describe their cytoprotective effect on H2O2-challenged IEC-6 cells. The C30-60% fraction of polysaccharides (CHP2) showed rapid stimulation of IEC-6 cell migration after wounding. Then, CHP2 was fractionated into four fractions, namely, CHP2-1, CHP2-2, CHP2-3 and CHP2-4. The CHP2-3 fraction possessed high scavenging activities against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and oxygen radical absorbance capacity (ORAC), in comparison with other fractions. And CHP2-3 was heteropolysaccharide with sulfuric esters, and it was mainly composed of glucose, galactose and arabinose and had an average molecular weight of 41.81 kDa. Pretreatment with CHP2 and CHP2-3 significantly improved the survival rate of H2O2-treated IEC-6 cells, and reduced intracellular reactive oxygen species (ROS) levels. Moreover, CHP2-3 also significantly decreased H2O2-mediated increases in the secretion of interleukin-1ß (IL-1ß) and interleukin-6 (IL-6), and attenuated nuclear factor-κB (NF-κB) p65 activation. These results indicate that CHP2-3 may play a vital role in reducing oxidative damage in IEC-6 cells via radical scavenging, decreasing proinflammatory factors secretion, inhibiting the NF-κB pathway, and thus, reducing cell apoptosis.

Protective Effects of Enteral Nutrition Supplemented with Crassostrea hongkongensis Polysaccharides Against 5-Fluorouracil-Induced Intestinal Mucosal Damage in Rats.

Chemotherapeutics, including 5-fluorouracil (5-FU), often damage the intestinal mucosal barrier and cause intestinal mucositis (IM). Supplementation with immunoregulatory polysaccharides from Crassostrea hongkongensis has been shown to positively influence the effectiveness and toxicity of 5-FU. Therefore, we studied the effects of oyster polysaccharides on 5-FU-induced intestinal mucosal damage in rats. The C30-60% ethanol-precipitated fraction of polysaccharides promoted IEC-6 cell proliferation and exhibited a maximal effect at a 0.0195 mg/mL concentration. Moreover, treatment with C30-60% polysaccharide-based nutrition formula (OPNF) partially prevented the 5-FU-induced degenerative changes in the histology and ultrastructure of small intestinal mucosa. In addition, the endotoxin level of rats fed with 5-FU and OPNF decreased to the normal control level. Furthermore, the 5-FU-induced increase of proinflammatory cytokine interleukin (IL)-2 and the decrease of anti-inflammatory cytokine IL-10 level in the peripheral blood were significantly attenuated by OPNF administration. In conclusion, Oyster C30-60% polysaccharides can ameliorate 5-FU-induced IM by partially preventing mucosal damage, reducing inflammation, and promoting immunity.