Synergetic effects and inhibition mechanisms of the polysaccharide-selenium nanoparticle complex in human hepatocarcinoma cell proliferation.

BACKGROUND: Active components from natural fungal products have shown promising potential as anti-tumor therapeutic agents. In the search for anti-tumor agents, research to overcome the drawbacks of high molecular weight and low bioavailability of pure polysaccharides, polysaccharide-conjugated selenium nanoparticles (SeNPs) has attracted much attention. RESULTS: A novel polysaccharide-selenium nanoparticle complex was produced, in which SeNPs were decorated with polysaccharide obtained from fermented mycelia broth of Lactarius deliciosus (FLDP). Transmission electron microscope, dynamic light scattering, and X-ray photoelectron spectroscopy were utilized to characterize the FLDP-SeNPs; and human hepatocarcinoma cell line (HepG2) was used to assess growth inhibition efficacy. The FLDP-SeNPs that were prepared had a spherical shape with the smallest mean diameter of 32 nm. The FLDP-SeNPs showed satisfactory dispersibility and stability after combination, demonstrating that a reliable consolidated structure had formed. The results revealed that FLDP-SeNPs had notable growth inhibition effects on HepG2 cells. They reduced the membrane potential of mitochondria significantly, increased the generation of reactive oxygen species, enhanced levels of both Caspase-3 and Caspase-9, and led to the nucleus in a wrinkled form. CONCLUSION: The FLDP-SeNPs could exert a synergetic toxicity reduction and inhibition enhancement effect on HepG2 cells by inducing early apoptosis, through mitochondria-mediated cytochrome C-Caspases and reactive oxygen species-induced DNA damage pathways. These results indicate that FLDP-SeNP treatment of HepG2 cells induced early apoptosis with synergetic efficacy, showing that FLDP-SeNPs can be useful as natural anti-tumor agents. © 2024 Society of Chemical Industry.

Prognostic value of GPC5 polymorphism rs2352028 and clinical characteristics in Chinese lung cancer patients.

Background: GPC5 rs2352028 is associated with the risk of lung cancer, but its relationship with lung cancer prognosis is unclear. Materials & methods: The authors collected blood samples from 888 patients with lung cancer and used a Cox proportional hazards model to analyze the association between prognosis and GPC5 polymorphism rs2352028. Results: GPC5 rs2352028 C > T was associated with a better prognosis. Patients with CT genotype had longer overall survival than those with CC genotype. Additionally, older and early-stage patients with CT + TT genotype had a lower risk of death than those with CC genotype. Conclusion: GPC5 rs2352028 C > T may play a protective role in patients with lung cancer and GPC5 rs2352028 may be a potential genetic marker for lung cancer prognosis.

Efficacy and safety of DOACs in patients with peripheral arterial disease: A systematic review and meta-analysis.

BACKGROUND: The efficacy and safety of direct oral anticoagulants (DOACs) in patients with peripheral arterial disease are not completely understood. Therefore, we conducted a meta-analysis to explore the effects of DOACs in this population. METHODS: We systematically searched the PubMed, Cochrane Library, and Web of Science till April 2020 for relevant randomized controlled trials and observational studies, with no linguistic restrictions. The efficacy outcomes were cardiovascular death, stroke, myocardial infraction, major adverse cardiovascular events (MACE), acute limb ischemia, amputation, and target lesion revascularization. The safety outcome was major bleeding events. Random effects risk ratios with 95% confidence intervals were calculated. RESULTS: A total four randomized controlled trials were included in this meta-analysis. Among peripheral arterial disease patients, DOACs did not reduce the risk of cardiovascular death (RR = 1.02 95%CI 0.75-1.37, P = 0.92), stroke (RR = 0.73 95%CI 0.46-1.14, P = 0.16), myocardial infraction (RR = 0.85 95%CI 0.70-1.03, P = 0.10), MACE (RR = 0.73 95%CI 0.46-1.14, P = 0.16), or amputation (RR = 0.73 95%CI 0.46-1.14, P = 0.16) compared with control. However, DOACs were associated with reduction in acute limb ischemia (RR = 0.67 95%CI 0.55-0.80, P < 0.01) and target lesion revascularization (RR = 0.89 95%CI 0.81-0.99, P = 0.02) at the expense of major bleeding events (RR = 1.43 95%CI 1.16-1.77, P < 0.01) compared with control. CONCLUSIONS: Based on current evidence, no significant difference in cardiovascular death, stroke, myocardial infraction, MACE, and amputation was found when DOACs were compared to antiplatelet monotherapy. The benefits of preventing target lesion revascularization and acute limb ischemia were balanced by amplified risk of major bleeding. Larger randomized controlled trials are needed to figure out the uncertainty around efficacy and safety of medications for peripheral arterial disease.

Specific immunohistochemical detection of the BRAF V600E mutation in primary and metastatic papillary thyroid carcinoma.

PURPOSE: To evaluate the clinical value of immunohistochemistry (IHC) using anti-BRAF V600E antibody (clone VE1) for specific detection of the BRAF V600E mutant protein in formalin-fixed paraffin-embedded papillary thyroid carcinoma (PTC) specimens. METHODS: A total of 118 PTC cases and 116 control cases processed between January 2008 and June 2010 were selected and created tissue microarrays (TMAs) for the study. BRAF V600E (VE1) IHC was performed on tissue sections from PTC cases to determine mutation status. Molecular tests (Sanger sequencing/ARMS) were used to confirm the BRAF V600E gene mutation in primary PTC. RESULTS: A uniformly cytoplasmic staining throughout the tumors was observed in IHC-positive cases. BRAF V600E was detected in 68.6% (81/118) of PTC samples by IHC and in 61.9% (73/118) by Sanger sequencing/ARMS. The overall concordance between IHC and Sanger sequencing/ARMS was 93.2% (110/118). The sensitivity and specificity of the BRAF V600E IHC was 100% (73/73) and 82.2% (37/45), respectively. Positive and negative predictive values were 90.1% (73/81) and 100% (37/37), respectively. Expression of the BRAF V600E mutant protein was detected in all of 59 cases of primary carcinoma and corresponding metastatic carcinoma in lymph nodes. The concordance between IHC staining in primary and metastatic PTC was 100% (59/59). CONCLUSION: IHC using VE1 antibody for detection of the BRAF V600E mutant protein expression in PTC showed high sensitivity and acceptable specificity, which are critical for diagnostic purposes. IHC staining for BRAF V600E showed uniformly cytoplasmic expression in both primary tumor and metastatic nodes. Therefore, IHC has high practical value for the detection of the BRAF V600E mutation in metastatic and primary PTC.

Aberrant Expression of Anaplastic Lymphoma Kinase in Ovarian Carcinoma Independent of Gene Rearrangement.

Ovarian carcinoma is the leading cause of death from gynecologic malignancies. The oncogenic role of anaplastic lymphoma kinase (ALK) is well characterized in many hematopoietic and solid tumors. ALK expression in ovarian carcinoma has been reported but the exact status of ALK protein and its association with clinicopathologic features requires further investigation. ALK expression was determined by immunohistochemistry in 110 primary ovarian carcinomas, including 85 cases of serous carcinoma and 25 cases of mucinous carcinoma. Fluorescence in situ hybridization (FISH) and real-time reverse transcription polymerase chain reaction (RT-PCR) were used for evaluating ALK translocation in ALK-positive ovarian carcinomas. Among 110 ovarian carcinomas, 23 (20.9%) cases were ALK positive by immunohistochemistry. All ALK-positive cases were ovarian high-grade serous carcinoma. ALK expression was detected in 23/85 (27.1%) ovarian serous carcinoma and 0/25 (0%) in ovarian mucinous carcinoma. None of the 23 ALK IHC-positive cases harbored ALK gene translocations by FISH or RT-PCR. ALK protein expression was associated with patient age, tumor stage, and histologic type. Specifically, the probability of ALK protein expression was significantly higher in high-grade serous carcinomas in older patients (above 50 y) with advanced disease (FIGO stage III and IV) compared with the low-grade serous and mucinous carcinomas in younger patients with relatively early disease. In conclusion, aberrant ALK expression is observed in ovarian serous carcinoma but not in mucinous carcinoma, is independent of gene translocation, and might be associated with progression and prognosis.

Synthesis and transmembrane anion/cation symport activity of a rigid bis(choloyl) conjugate functionalized with guanidino groups.

A rigid bis(choloyl) conjugate functionalized with guanidino groups was synthesized and fully characterized on the basis of NMR ((1)H and (13)C) and ESI MS (LR and HR) data. Its transmembrane ionophoric activity across egg-yolk l-α-phosphatidylcholine-based liposomal membranes was investigated by means of chloride ion selective electrode technique and pH discharge assay. The data indicate that under the assay conditions, this conjugate was capable of promoting the transport of anions, presumably via a cation/anion symport process. A Hill analysis reveals that two molecules of this compound are assembled into the transport-active species.

Synthesis and potent ionophoric activity of a squaramide-linked bis(choloyl) conjugate.

A squaramide-linked bis(choloyl) conjugate was synthesized and fully characterized on the basis of NMR ((1)H and (13)C) and ESI MS (LR and HR) data. Fluorescence and chloride ion selective electrode assays indicate that this compound exhibits potent ionophoric activity across egg-yolk L-α-phosphatidylcholine-based liposomal membranes, presumably via an anion-modulating anion-cation co-transport/symport process. A Hill analysis reveals that three molecules of this compound are assembled into the transport-active species.

[Assessment of HER2 gene amplification in breast cancer: a comparison of dual-color in-situ hybridization and fluorescence in-situ hybridization].

OBJECTIVE: To compare dual-color in-situ hybridization (DISH) with fluorescence in situ hybridization(FISH) in evaluating the human HER2 gene status in invasive breast cancer. METHODS: HER2 gene status in 110 cases of breast invasive ductal carcinomas with a 2+ score on immunohistochemistry (IHC) was investigated by FISH and DISH. The 2007 and 2013 ASCO (American Society of Clinical Oncology)/CAP (College of American Pathologists) HER2 guideline were used respectively to evaluate the agreement between these two techniques. RESULTS: (1) Using the 2007 ASCO/CAP guideline, the overall concordance between FISH and DISH was 97.3% (107/110). Fifty of 51 samples with amplification by FISH were also detected by DISH and the remaining one sample was equivocal.Eight of 10 equivocal samples by FISH were equivocal by DISH and the remaining two samples were negative. Forty-nine samples with no amplification by FISH were all negative by DISH. The concordance was 98.0%, 8/10 and 100.0% respectively for the FISH positive, equivocal and negative groups. (2) Using the 2013 ASCO/CAP guideline, the overall concordance between FISH and DISH was 90.0% (99/110). Fifty-three of 55 samples with amplification by FISH were also detected by DISH and the remaining two were equivocal and negative respectively. Two of 12 equivocal samples by FISH were equivocal by DISH and the remaining ten samples were negative in 7 cases and equivocal in 3 cases. Forty-three samples with no amplification by FISH were all negative by DISH. The concordance was 96.4%, 3/12 and 100.0% respectively for the FISH positive, equivocal and negative groups. Pearson correlation analysis indicated that the HER2 status detected by FISH and DISH were significantly correlated with each other (R=0.584, P<0.01). CONCLUSIONS: There is a high concordance between DISH and FISH for assessing the HER2 gene status in invasive breast cancer. DISH is a new option for assessing HER2 gene status of breast cancer in clinical practice. The clinical significance of the discordance between DISH and FISH in equivocal cases warrants further study.

Protective Mechanism of Polysaccharide ORP-1 Isolated from Oudemansiella raphanipes against Age-Related Cognitive Decline through the Microbiota-Gut-Brain Axis.

Age-related cognitive decline is primarily attributed to the progressive weakening of synaptic function and loss of synapses, while age-related gut microbial dysbiosis is known to impair synaptic plasticity and cognitive behavior by metabolic alterations. To improve the health of the elderly, the protective mechanisms of Oudemansiella raphanipes polysaccharide (ORP-1) against age-related cognitive decline are investigated. The results demonstrate that ORP-1 and its gut microbiota-derived metabolites SCFAs restore a healthy gut microbial population to handle age-related gut microbiota dysbiosis mainly by increasing the abundance of beneficial bacteria Dubosiella, Clostridiales, and Prevotellaceae and reducing the abundance of harmful bacteria Desulfovibrio, strengthen intestinal barrier integrity by abolishing age-related alterations of tight junction (TJ) and mucin 2 (MUC2) proteins expression, diminish age-dependent increase in circulating inflammatory factors, ameliorate cognitive decline by reversing memory- and synaptic plasticity-related proteins levels, and restrain hyperactivation of microglia-mediated synapse engulfment and neuroinflammation. These findings expand the understanding of prebiotic-microbiota-host interactions.

Synthesis and ionophoric activities of functionalized bis(choloyl) conjugates with a rigid core.

Three bis(choloyl) conjugates bearing a rigid p-phenylenediamine/p-bis(aminomethyl)benzene linker and amino/acetamido groups were synthesized, and fully characterized on the basis of (1)H NMR, ESI-MS and HRMS. Their ionophoric activities were investigated by means of pH discharge assay. The results indicate that these conjugates exhibit potent ionophoric activities across egg-yolk l-α-phosphatidylcholine (EYPC)-based liposomal membranes, via a cation/proton antiport mechanism. They show moderate ion selectivity among alkali metal ions. Of the three conjugates, the ones having amino groups transport alkali metal ions in the order of Na(+)>Li(+)>K(+)≈Rb(+)≈Cs(+), whereas the one having acetamido groups functions in the order of Li(+)>Na(+)>K(+)≈Rb(+)≈Cs(+).

Synthesis and anionophoric activities of dimeric polyamine-sterol conjugates: the impact of rigid vs. flexible linkers.

Two dimeric spermine-choloyl conjugates were synthesized and found to be capable of promoting the transport of anions across egg-yolk L-α-phosphatidylcholine-based liposomal membranes, via an anion-exchange mechanism and with moderate selectivity with respect to monoanionic ions. A Hill analysis indicated that these two conjugates exhibited similar aggregation behaviors. However, the conjugate bearing a rigid p-bis(aminomethyl)benzene moiety functioned more efficiently than the analogue having a flexible putrescine linker.

Encapsulation of tea polyphenols into high amylose corn starch composite nanofibrous film for active antimicrobial packaging.

Starch-based composite nanofibrous films loaded with tea polyphenols (TP) were successfully fabricated through electrospinning high amylose corn starch (HACS) with aid of polyvinyl alcohol (PVA), referred as HACS/PVA@TP. With the addition of 15 % TP, HACS/PVA@TP nanofibrous films exhibited enhanced mechanical properties and water vapor barrier capability, and their hydrogen bonding interactions were further evidenced. TP was slowly released from the nanofibrous film and followed Fickian diffusion mechanism, which achieved the controlled sustained release of TP. Interesting, HACS/PVA@TP nanofibrous films effectively improved antimicrobial activities against Staphylococcus aureus (S. aureus) and prolonged the shelf life of strawberry. HACS/PVA@TP nanofibrous films showed superior antibacterial function by by destroying cell wall and cytomembrane, and degrading existing DNA fragments, stimulating excessive intracellular reactive oxygen species (ROS) generation. Our study demonstrated that the functional electrospun Starch-based nanofibrous films with enhanced mechanical properties and superior antimicrobial activities were potential for the application in active food packaging and relative areas.

[KRAS and BRAF gene mutations in correlation with clinicopathologic features of colorectal carcinoma in Chinese].

OBJECTIVE: To retrospectively analyze KRAS and BRAF gene mutation features in Chinese colorectal cancer (CRC) and their clinicopathologic relationship. METHODS: 557 colorectal cancer cases were collected, including 325 colon cancer and 232 rectal cancer. PCR amplification and DNA sequencing were used to detect mutations in exon 2 of KRAS gene and exon 15 of BRAF gene mutation. RESULTS: (1) KRAS mutation was found in 40.4% (225/557) colorectal cancer. The most common mutation locations were in codon 12(79.1%, 178/225) and codon 13 (20.4%, 46/225). The most common mutation types were GGT > GAT (G12D) (37.8%, 85/225), GGT > GTT(G12V) (20.0%, 45/225) in codon 12 and GGC > GAC (G13D) in codon 13 (19.6%, 44/225). These three point mutations accounted 77.3% (174/225) in total KRAS gene mutation cases. All cases showed only one of point mutation types. (2) Among 557 CRC cases, KRAS mutation was significantly higher in female (46.2%, 92/199) than in man (37.2%, 133/358; P < 0.05). KRAS gene codon 13 mutation was higher in right colon cancer (11.3%, 12/106) than that in left colon cancer (4.8%, 6/124), but it didn't show any statistical significance (P > 0.05). (3) BRAF gene mutation was 5.1% (10/197) in colorectal cancer and 8/10 were the point mutation of GTG > GAG (V600E). Eight colorectal cancer cases with GTG > GAG (V600E) were not showing KRAS gene mutation. Both two cases with mutation on codon 600 (GTG > ATG, V600M) and codon 606 (GGG > AGT, G606S) showed codon 12 mutation of KRAS gene. (4) BRAF (V600E) gene mutation was higher in female (8.5%, 6/71) than that in male (1.6%, 2/126; P = 0.05); BRAF mutation in colon cancer (8.3%, 6/72) was higher than that in rectum cancer (2.1%, 2/94), but hadn't statistical significance (P > 0.05). CONCLUSIONS: (1) Codon 12, 13 in KRAS gene and codon 600 in BRAF gene are the most common mutation points in Chinese colorectal cancer. KRAS and BRAF mutations are mutually exclusive. (2) KRAS and BRAF gene mutation is higher in female than that in male, suggesting that RAS-RAF-MAPK signal pathway is probably related to hormones directly or indirectly. (3) There is a trend that codon 13 mutation in KRAS and codon 600 mutation in BRAF in right colon cancer are higher than that in left colon cancer, respectively, however, which needs more cases to be further verified.

[Detection of chromosomal translocations involving ALK gene in anaplastic large cell lymphoma by fluorescence in-situ hybridization and its clinical significance].

OBJECTIVE: To investigate clinicopathologic features and clinical value of the chromosomal translocation involving anaplastic lymphoma kinase (ALK) in anaplastic large cell lymphoma (ALCL) by fluorescence in situ hybridization (FISH). METHODS: A total of 55 cases, including 45 cases of ALCL and 10 reactive lymphoid hyperplasia, were collected during 1999 to 2006 in the Department of Pathology, Fudan University Shanghai Cancer Center, and Xinhua Hospital Affiliated to Shanghai Jiaotong University. All cases were studied by FISH using dual color break apart probes of ALK for detection of chromosomal translocation, compared with the previous results of immunohistochemistry (IHC) and reverse-transcriptase polymerase chain reaction (RT-PCR) for the detection of ALK aberrations. RESULTS: The result of FISH showed that the clear red and green fluorescence signals were detected in 38 cases of ALCL, in which conspicuous split signals were observed in tumor cells in 24 cases (63.2%), suggesting the rearrangement of the ALK locus, with multiple copies of ALK gene in one case. In addition, the rearrangement of the ALK locus was not identified in 14 of 38 cases (36.8%); and the FISH results were unable to be evaluated in 7 cases, because no fluorescent signals involving ALK gene were found or signals were too weak to be analyzed. The concordance for the detection ALK aberrations in ALCL between FISH and RT-PCR, FISH and IHC were both statistically significant (P < 0.01). Chromosomal translocation involving ALK gene was not found in all 10 cases of reactive lymphoid hyperplasia. CONCLUSIONS: ALCL is an entity of lymphoma characterized by special clinical presentation, morphology, and ALK aberrations. FISH is helpful for detection of the chromosomal translocations involving ALK in ALCL, however, the detection efficiency by FISH may be affected by storage time of the paraffin-embedded tissue; and therefore combined detection with IHC and RT-PCR could complement each other and help for differential diagnosis of ALK(+)ALCL from ALK(-)ALCL.

Extraction, purification, structural characterization, and gut microbiota relationship of polysaccharides: A review.

Intestinal dysbiosis is one of the major causes of the occurrence of metabolic syndromes, such as obesity, diabetes, nonalcoholic fatty liver disease, and cardiovascular diseases. Polysaccharide-based microbial therapeutic strategies have excellent potential in the treatment of metabolic syndromes, but the underlying regulatory mechanisms remain elusive. Identification of the internal regulatory mechanism of the gut microbiome and the interaction mechanisms involving bacteria and the host are essential to achieve precise control of the gut microbiome and obtain valuable clinical data. Polysaccharides cannot be directly digested; the behavior in the intestinal tract is considered a "bridge" between microbiota and host communication. To provide a relatively comprehensive reference for researchers in the field, we will discuss the polysaccharide extraction and purification processes and chemical and structural characteristics, focusing on the polysaccharides in gut microbiota through the immune system, gut-liver axis, gut-brain axis, energy axis interactions, and potential applications.

Reducing tumescent anesthetic injection pain by topical anesthesia pretreatment among patients undergoing endovenous radiofrequency ablation of varicose veins: A double-blind randomized controlled trial.

OBJECTIVES: Tumescent anesthesia frequently causes the intraoperative and postoperative pain during radiofrequency ablation (RFA) of varicose veins. We have to find a way to reduce pain caused by these injections. This randomized controlled trial investigated the effectiveness of topical anesthesia pretreatment (TAP) on relieving needle puncture pain during administration of tumescent anesthesia among patients undergoing RFA of varicose veins. METHODS: Eligible patients treated with RFA were recruited and randomized to either application of TAP with lidocaine-prilocaine cream (EMLA) or water-based cream (placebo). The primary outcome was patient described pain scores on the visual analogue scale (VAS) at different time points during the procedure. Secondary outcomes were technical success rate, complications, satisfaction level, expense, and extra analgesia use. RESULTS: Sixty-two patients were randomized: 32 to EMLA and 30 to placebo. Both groups had comparable baseline demographics, CEAP classification, and Venous Clinical Severity Score (VCSS). Less tumescent anesthetic needle puncture pain was found in the EMLA group (22 ± 7 vs 42 ± 8, p < .01). Pain scores of other time points were equivalent. There was less pain in EMLA pretreated area compared to non-pretreated area in the same patient during needle puncture (22 ± 7 vs 45 ± 7, p < .01), and similar phenomena did not appear in the placebo group. There was no statistical difference in complications, satisfaction level, expense, and technical success between the two groups. And no extra analgesia was used in all patients. CONCLUSION: We recommend the routine use of TAP to reduce the needle puncture pain during tumescent anesthesia in RFA of lower extremity varicose veins.

The crude guava polysaccharides ameliorate high-fat diet-induced obesity in mice via reshaping gut microbiota.

Guava is a popular fruit consumed worldwide with beneficial effects in regulation of glucose and lipid metabolism. Although polysaccharides are a major phytochemical component of guava, to date, the alleviative effects of polysaccharides from the guava fruit against diet-induced obesity remain unclear. The relationship between the anti-obesity effects of guava polysaccharide (GP) and gut microbiota is unknown. In current study, seven-week-old C57BL/6 mice were fed high-fat diet (HFD) supplemented with GP (100 mg/kg) by oral gavage for 11 weeks. GP supplementation alleviated HFD-induced body weight gain and visceral obesity, and reduced serum cholesterol, triglyceride, and LDL-C levels. In addition, GP ameliorated insulin resistance and prevented hepatic lipid accumulation and meta-inflammation in both liver and adipose tissues in obese mice. Remarkably, GP treatment restored the Firmicutes/Bacteroidetes ratio, induced growth of beneficial bacteria including Clostridium XlVa, Parvibacter, and Enterorhabdus, and decreased in inflammation-related bacteria Mucispirillum in mice fecal samples, accompanied with enhanced production of colonic short chain fatty acids especially butyric acid. However, the metabolic benefits of GP diminished in antibiotics-treated HFD-fed mice. Overall, GP improved metabolic profiles in HFD-induced obese mice via the mediation of gut microbiota-dependent pathways. GP might be developed and utilized as prebiotics in nutraceutical and food industry.

Polysaccharide ORP-1 isolated from Oudemansiella raphanipes ameliorates age-associated intestinal epithelial barrier dysfunction in Caco-2 cells monolayer.

Age-associated increase in intestinal permeability is known to relate with gut microbiota dysbiosis and loss of epithelial tissue integrity. To improve healthy aging and prevent age-associated chronic disabilities, the protective potential of polysaccharides from Oudemansiella raphanipes (ORP-1) against age-associated intestinal epithelial barrier dysfunction in d-galactose-induced Caco-2 cells monolayer was investigated. In-vitro results demonstrated that ORP-1 can restore a healthy gut microbial population to handle age-related gut microbiota dysbiosis mainly by facilitating the proliferation and adhesion of probiotics Lactobacillus acidophilus (L. acidophilus) and Bifidobacterium bifidum (B. bifidum) to compete with intestinal pathogenic Escherichia coli (E. coli) for ecological niches and nutrition. Meanwhile, ORP-1 strengthened the intestinal structural integrity primarily by abolishing the aggravation of apoptosis and the age-associated alterations of tight junction (TJ) proteins expression in intestine. These findings highlighted that ORP-1 could be a potential functional food component with preventive utility against age-associated intestinal barrier injury.

Antibacterial effect and mechanism against Escherichia coli of polysaccharides from Armillariella tabescens mycelia.

The objectives of this study were (1) to prepare Armillariella tabescens mycelia polysaccharides (PAT) with remarkably growth inhibitory effect on typical food-borne pathogenic bacteria using a green and efficient polyamide method and (2) to explore the antibacterial mechanism of PAT for use as a natural antibacterial agent. The sugar and uronic acid contents of PAT were 93.41% and 12.24%, respectively. PAT could inhibit the growth of Escherichia coli, Proteus vulgaris, Bacillus subtilis, and Staphylococcus aureus cells, with minimum inhibitory concentrations of 0.5, 1.0, 4.0, and 4.0 mg/mL, respectively. Ultra-high-resolution field emission scanning electron microscopy and high-resolution transmission electron microscopy analysis revealed cell wall and membrane rupture of E. coli treated with PAT. Further, 0.5-4.0 mg/mL PAT was found to significantly (P < 0.01) and concentration-dependently increase the conductivity of the broth, exudation of the intracellular protein, and alkaline phosphatase and ß-galactosidase activities. Confocal laser scanning microscopy revealed morphological changes in E. coli DNA after PAT treatment and intracellular reactive oxygen species accumulation; flow cytometry revealed E. coli cell apoptosis. Our findings provide a theoretical basis and technical support for the development of PAT as a natural antibacterial product.

Characterization and immunomodulatory effect of an alkali-extracted galactomannan from Morchella esculenta.

In our continuous exploration for bioactive polysaccharides, a novel polysaccharide FMP-2 was isolated and purified from the fruiting bodies of Morchella esculenta by alkali-assisted extraction. FMP-2 had an average molecular weight of 1.09 × 106 Da and contained mannose, glucuronic acid, glucose, galactose, and arabinose in a molar ratio of 4.10:0.22:1.00:5.75:0.44. The backbone of FMP-2 mainly consisted of 1,2-α-D-Galp, 1,6-α-D-Galp, and 1,4-α-D-Manp, with branches of 1,4,6-α-D-Manp and 1,2,6-α-D-Galp. FMP-2 can stimulate phagocytosis and promote the secretion of NO, ROS, and cytokines like IL-6, IL-1ß, and TNF-α in RAW264.7 cells ranging from 25 to 400 µg/mL. FMP-2 had great repairing effect on the immune injury of zebrafish induced by chloramphenicol. The phagocytosis ability of zebrafish macrophages and the proliferation of neutrophils can be greatly enhanced by polysaccharide FMP-2 with concentrations from 50 to 200 µg/mL. These findings suggest that FMP-2 might be used as a potential immunomodulator in the food and pharmaceutical industries.