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Scientific Reports May 2024Breast cancer patients often have a poor prognosis largely due to lack of effective targeted therapy. It is now well established that monosaccharide enhances growth...
Breast cancer patients often have a poor prognosis largely due to lack of effective targeted therapy. It is now well established that monosaccharide enhances growth retardation and chemotherapy sensitivity in tumor cells. We investigated whether D-arabinose has capability to restrict the proliferation of tumor cells and its mechanism. Here, we report that D-arabinose induced cytotoxicity is modulated by autophagy and p38 MAPK signaling pathway in breast cancer cell lines. The proliferation of cells was evaluated by CCK-8 and Colony formation assay. The distribution of cells in cell cycle phases was analyzed by flow cytometry. Cell cycle, autophagy and MAPK signaling related proteins were detected by western blotting. Mouse xenograft model was used to evaluate the efficacy of D-arabinose in vivo. The proliferation of cells was dramatically inhibited by D-arabinose exposure in a dose-dependent manner, which was relevant to cell cycle arrest, as demonstrated by G2/M cell cycle restriction and ectopic expression of cell cycle related proteins. Mechanistically, we further identified that D-arabinose is positively associated with autophagy and the activation of the p38 MAPK signaling in breast cancer. In contrast, 3-Ma or SB203580, the inhibitor of autophagy or p38 MAPK, reversed the efficacy of D-arabinose. Additionally, D-arabinose in vivo treatment could significantly inhibit xenograft growth of breast cancer cells. Our findings were the first to reveal that D-arabinose triggered cell cycle arrest by inducing autophagy through the activation of p38 MAPK signaling pathway in breast cancer cells.
Topics: Autophagy; Humans; Breast Neoplasms; Animals; Female; p38 Mitogen-Activated Protein Kinases; Mice; Arabinose; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; MAP Kinase Signaling System; Xenograft Model Antitumor Assays; Mice, Nude; Mice, Inbred BALB C
PubMed: 38755221
DOI: 10.1038/s41598-024-61309-7 -
International Journal of Systematic and... May 2024A novel actinobacterium, strain ZYX-F-186, was isolated from marine sediment sampled on Yongxing Island, Hainan Province, PR China. Based on the results of 16S rRNA gene...
A novel actinobacterium, strain ZYX-F-186, was isolated from marine sediment sampled on Yongxing Island, Hainan Province, PR China. Based on the results of 16S rRNA gene sequence analysis, strain ZYX-F-186 belongs to the genus , with high similarity to KK1-3 (98.3 %), K11-0047 (98.1 %), K09-0627 (98.1 %), K11-0057 (97.9 %), K07-0523 (97.7 %), and RD004123 (97.7 %). Phylogenetic analysis of 16S rRNA gene sequences showed that the strain formed a single subclade in the genus . The novel isolate contained -diaminopimelic acid, d-glutamic acid, glycine, d-alanine, and l-lysine in the cell wall. The whole-cell sugars were xylose, arabinose, ribose, and rhamnose. The predominant menaquinones were MK-9(H), MK-9(H), and MK-9(H). The characteristic phospholipids were phosphatidylethanolamine, phosphatidylinositol, phosphatidylmethylethanolamine, phosphatidylglycerol, and an unknown phospholipid. The major fatty acids (>5 %) were iso-C, anteiso-C, and iso-C. Genome sequencing showed a DNA G+C content of 71.9 mol%. Low average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values demonstrated that strain ZYX-F-186 could be readily distinguished from its closely related species. Based on its phylogenetic, chemotaxonomic, and physiological characteristics, strain ZYX-F-186 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is ZYX-F-186 (=CGMCC 4.8025=CCTCC AA 2023025=JCM 36507).
Topics: Geologic Sediments; Phylogeny; RNA, Ribosomal, 16S; Base Composition; China; DNA, Bacterial; Fatty Acids; Bacterial Typing Techniques; Sequence Analysis, DNA; Phospholipids; Vitamin K 2; Nucleic Acid Hybridization; Cell Wall
PubMed: 38752995
DOI: 10.1099/ijsem.0.006393 -
Gut Microbes 2024Members of the genus are commonly found in the human gut and are known to utilize complex carbohydrates that are indigestible by the human host. Members of the subsp....
Members of the genus are commonly found in the human gut and are known to utilize complex carbohydrates that are indigestible by the human host. Members of the subsp. taxon can metabolize various plant-derived carbohydrates common to the human diet. To metabolize such polysaccharides, which include arabinoxylan, bifidobacteria need to encode appropriate carbohydrate-active enzymes in their genome. In the current study, we describe two GH43 family enzymes, denoted here as AxuA and AxuB, which are encoded by subsp. NCIMB 8809 and are shown to be required for cereal-derived arabinoxylan metabolism by this strain. Based on the observed hydrolytic activity of AxuA and AxuB, assessed by employing various synthetic and natural substrates, and based on analyses, it is proposed that both AxuA and AxuB represent extracellular α-L-arabinofuranosidases with distinct substrate preferences. The variable presence of the and genes and other genes previously described to be involved in the metabolism of arabinose-containing glycans can in the majority cases explain the (in)ability of individual subsp. strains to grow on cereal-derived arabinoxylans and arabinan.
Topics: Xylans; Glycoside Hydrolases; Edible Grain; Bifidobacterium longum; Substrate Specificity; Bacterial Proteins; Humans
PubMed: 38752423
DOI: 10.1080/19490976.2024.2353229 -
International Journal of Biological... Jun 2024Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterised by neuroinflammation, for which gut dysbiosis may be implicated. Our previous study...
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterised by neuroinflammation, for which gut dysbiosis may be implicated. Our previous study showed that treatment with Pseudostellaria heterophylla aqueous extract and one of its cyclopeptides, heterophyllin B, attenuate memory deficits via immunomodulation and neurite regeneration. However, whether Pseudostellaria heterophylla polysaccharide (PH-PS) exerts neuroprotective effects against AD and its underlying mechanisms remain unclear. The infrared spectrum, molecular weight, and carbohydrate composition of the PH-PS were determined. The results showed that PH-PS (Mw 8.771 kDa) was composed of glucose (57.78 %), galactose (41.52 %), and arabinose (0.70 %). PH-PS treatment ameliorated learning and spatial memory deficits, reduced amyloid β build-up, and suppressed reactive glia and astrocytes in 5 × FAD mice. 16S rRNA sequencing further showed that PH-PS remodelled the intestinal flora composition by promoting probiotic microbiota, such as Lactobacillus, Muribaculum, Monoglobus, and [Eubacterium]_siraeum_group, and suppressing inflammation-related UCG-009 and Blautia. Additionally, PH-PS restored intestinal barrier function; ameliorated peripheral inflammation by reducing the secretion of inflammatory cytokines, thereby converting M1 microglia and A1 astrocyte toward beneficial M2 and A2 phenotypes; and contributed to Aβ plaques clearance by upregulation of insulin degradation enzyme and neprilysin. Collectively, our findings demonstrate that PH-PS may prevent the progression of AD via modulation of the gut microbiota and regulation of glial polarisation, which could provide evidence to design a potential diet therapy for preventing or curing AD.
Topics: Animals; Alzheimer Disease; Gastrointestinal Microbiome; Polysaccharides; Mice; Brain; Amyloid beta-Peptides; Disease Models, Animal; Juglandaceae; Male; Neuroprotective Agents
PubMed: 38750854
DOI: 10.1016/j.ijbiomac.2024.132372 -
Environmental Science and Pollution... May 2024This study describes the extraction and characterization of the hemicellulosic autohydrolysates (HAHs) derived from rice straw (RS) and vascular aquatic weeds like Typha...
Valorization of rice straw and vascular aquatic weeds for sustainable prebiotic hemicellulosic autohydrolysate production: Extraction, characterization and fermentability.
This study describes the extraction and characterization of the hemicellulosic autohydrolysates (HAHs) derived from rice straw (RS) and vascular aquatic weeds like Typha angustifolia (TA) and Ceretophyllum demersum (CD). It further explores their capacity to sustain the proliferation of selected lactic acid bacteria (i.e., prebiotic activity) isolated from milk samples. To fractionate HAH from RS, TA and CD hot water extraction (HWE) method was used and RS, TA, and CD biomasses yielded 6.8, 4.99 and 2.98% of HAH corresponding to the hemicellulose extraction efficiencies of 26.15 ± 0.8%, 23.76 ± 0.6%, and 18.62 ± 0.4% respectively. The chemical characterization of HAH concentrates through HPLC showed that they comprised galactose, arabinose, xylose and glucose. The total phenol content of the RS, TA and CD-derived HAH concentrates were 37.53, 56.78 and 48.08 mg GAE/g. The five lactic acid bacteria (LAB) isolates Q1B, Q2A, Q3B, G1C and G2B selected for prebiotic activity assays generated mixed responses with the highest growth in RS-HAH for Q2A and the least in TA-HAH for Q3B. Further, the isolates Q2A, Q3B, G1C, and G2B, which showed the highest growth performance, were identified through MALDI-TOF and 16S rRNA sequencing as Lactobacillus brevis. All the tested LAB isolates showed diauxic growth in crude HAH preparations to maximize the utilization of carbon resources for their proliferation. This suggests that the selected LAB isolates are efficient degraders of hemicellulosic sugars. This paves the way for the valorization of lignocellulosic biomass to produce prebiotic hemicellulosic autohydrolysate and consequently enhances environmental sustainability by improving resource efficiency.
Topics: Prebiotics; Oryza; Polysaccharides; Fermentation
PubMed: 38744764
DOI: 10.1007/s11356-024-33611-4 -
International Journal of Biological... Jun 2024The present study aimed to investigate the structural and physicochemical characteristics of alkali-extracted pectic polysaccharide (AkPP) and to evaluate its prebiotic...
The present study aimed to investigate the structural and physicochemical characteristics of alkali-extracted pectic polysaccharide (AkPP) and to evaluate its prebiotic effects. AkPP was obtained from pumpkin pulp using an alkaline extraction method. AkPP, which had a molecular weight (Mw) of mainly 13.67 kDa and an esterification degree of 9.60%, was composed mainly of galacturonic acid (GalA), rhamnose (Rha), galactose, and arabinose. The ratio of the homogalacturonan (HG) region to the rhamnogalacturonan-I (RG-I) region in AkPP was 48.74:43.62. In the nuclear magnetic resonance spectrum, the signals indicating α-1,4-linked D-GalA, α-1,2-linked L-Rha, α-1,2,4-linked L-Rha residues were well resolved, demonstrating the presence of the HG and RG-I regions in its molecular structure. Collectively, AkPP was low methoxyl pectin rich in the RG-I region with short side chains and had a low Mw. Thermal analysis revealed that AkPP had good thermal stability. Compared to inulin, AkPP more effectively promoted the proliferation of Lactobacillus acidophilus, Lacticaseibacillus rhamnosus GG, Lacticaseibacillus casei, and Lacticaseibacillus paracasei and the production of lactic, acetic, and propionic acids. This study presents the unique structural features of AkPP and provides a scientific basis for further investigation of the potential of AkPP as a promising prebiotic.
Topics: Pectins; Prebiotics; Cucurbita; Molecular Weight; Polysaccharides; Rhamnose; Alkalies; Solutions; Hexuronic Acids
PubMed: 38740154
DOI: 10.1016/j.ijbiomac.2024.132311 -
Carbohydrate Research Jun 2024We discovered an unusual triflic acid-promoted oligomerization of arabinofuranosides during glycosylation of the primary hydroxy group of α-(1 → 5)-linked...
We discovered an unusual triflic acid-promoted oligomerization of arabinofuranosides during glycosylation of the primary hydroxy group of α-(1 → 5)-linked tetraarabinofuranoside bearing 4-(2-chloroethoxy)phenyl aglycone with α-(1 → 5), β-(1 → 2)-linked tetraarabinofuranoside containing N-phenyltrifluoroacetimidoyl leaving group, which led to octa-, dodeca- and hexadecaarabinofuranosides. The possible mechanism of triflic acid-promoted oligomerization was proposed. The choice of promoter was found to be a critical factor for the discovered oligomerization of arabinofuranosides. The obtained octa-, dodeca- and hexadecaarabinofuranosides may serve as useful blocks in the synthesis of oligosaccharide fragments of polysaccharides of Mycobacterium tuberculosis.
Topics: Glycosylation; Arabinose; Mesylates; Mycobacterium tuberculosis; Carbohydrate Conformation
PubMed: 38740000
DOI: 10.1016/j.carres.2024.109141 -
Food Chemistry Sep 2024This study examines the volumetric, viscometric and UV-vis characteristics of L-Citrulline in water and aqueous saccharides at atmospheric pressure across the whole...
Exploring the effects of saccharides on the solvation behaviour of L-Citrulline in aqueous medium: Volumetric, transition state theory, transfer parameters and spectroscopic approach.
This study examines the volumetric, viscometric and UV-vis characteristics of L-Citrulline in water and aqueous saccharides at atmospheric pressure across the whole concentration range and the absorber operating temperature range of 293.15 K -313.15 K. Density, partial molar volume, apparent molar isobaric expansion, Hepler's constant and hydration number were among the examined volumetric parameters, and viscosity coefficients, viscosity deviation and free energy for viscous flow activation were among the examined viscometric parameters. Stronger interactions between L-Citrulline and L-Arabinose were indicated by the increase in the transfer characteristics in the following order: L-Arabinose > D-xylose. A comparison of the taste behaviours of L-Citrulline in water and in an aqueous solution of saccharides has also been attempted. L-Citrulline interacts with all solvents in a significant way, as evidenced by the UV-visible spectra suggested by the shift in UV-visible absorption maxima that correspond with a rise in L-Citrulline content in the solvent systems chosen.
Topics: Citrulline; Viscosity; Water; Spectrophotometry, Ultraviolet; Solvents
PubMed: 38733685
DOI: 10.1016/j.foodchem.2024.139554 -
Molecules (Basel, Switzerland) Apr 2024Two unreported heteropolysaccharides, denoted as YCJP-1 and YCJP-2, were isolated from the herbs of . YCJP-1 was a heteropolysaccharide composed of glucose, galactose,...
Two unreported heteropolysaccharides, denoted as YCJP-1 and YCJP-2, were isolated from the herbs of . YCJP-1 was a heteropolysaccharide composed of glucose, galactose, arabinose, mannose, rhamnose, and a minor proportion of uronic acids, with the molecular weight mainly distributed in the 74,475-228,443 Da range. YCJP-2 was mainly composed of glucose, mannose, and galactose, with the molecular weights ranging from 848 to 5810 Da. To further evaluate the anti-gastric cancer effects of , the inhibitory effects of the crude polysaccharide (YCJP) and the purified polysaccharides (YCJP-1 and YCJP-2) were determined using a CCK-8 assay and colon-forming assay on MGC-803 and AGS gastric cancer cell lines. Our results showed that YCJP, YCJP-1, and YCJP-2 possess prominent inhibitory effects on the proliferation of MGC-803 and AGS cells, and the AGS cell was more sensitive to YCJP, YCJP-1, and YCJP-2. Moreover, YCJP-2 demonstrated superior anti-gastric cancer effects compared to YCJP-1. This could potentially be attributed to YCJP-2's higher glucose content and narrower molecular weight distribution.
Topics: Humans; Polysaccharides; Stomach Neoplasms; Cell Line, Tumor; Cell Proliferation; Plant Extracts; Antineoplastic Agents, Phytogenic; Molecular Weight; Caryophyllaceae
PubMed: 38731534
DOI: 10.3390/molecules29092043