Effect of beta- and alpha-glucans on immune modulating factors expression in enterocyte-like Caco-2 and goblet-like LS 174T cells

Dynamic bond crosslinked maca polysaccharide hydrogels with reactive oxygen species scavenging and antibacterial effects on infected wound healing

In this study, a polysaccharide fragment with antioxidant and reactive oxygen species (ROS) scavenging activities was extracted from Maca (Lepidium meyenii Walp.) and subjected to structural analyses. The fragment, characterized by the α-D-Glcp-(1 → terminal group of the main chain linked to the →4)-Glcp-(1 → end unit through an O-6 bond and the O-3 bond of 1-3-4Glcp, was modified by introducing dialdehyde structures on its glucose units. It was then crosslinked with N-carboxymethyl chitosan via the Schiff base reaction to create a multifunctional hydrogel with antibacterial and ROS scavenging properties. Polyvinyl alcohol was incorporated to form a double crosslinked gel network, and the addition of silver nanoparticles enhanced its antibacterial efficacy. This gel system can scavenge excess ROS, mitigate wound inflammation, eradicate harmful bacteria, and aid in the restoration of skin microecology. The multifunctional maca polysaccharide hydrogel shows significant potential as a medical dressing for the treatment of infected wounds.

Chickpea Seed Flours Improve the Nutritional and the Antioxidant Profiles of Traditional Shortbread Biscuits: Effects of In Vitro Gastrointestinal Digestion

Functional gluten-free biscuits enriched with commercial and landrace non-commercial chickpea flours were designed and compared with a traditional shortbread biscuit. They were analyzed in sensory attributes, amino acid profile, and antioxidant properties. Subsequently, the biscuits were digested in vitro to evaluate protein hydrolysis, amino acid bioaccessibility, phenolic compounds release, and antioxidant markers. The presence of chickpea flours provided golden color and heightened biscuit hardness and fracturability (especially in non-commercial), increasing crispness and reducing brittleness. The protein hydrolysis was similar among samples (≈15%), except for one of the non-commercial (≈20%). Amino acids such as arginine, phenylalanine, leucine, tyrosine, and lysine exhibited the highest bioaccessibilities. Incorporating chickpea flour improved the antioxidant activity and polyphenol content in undigested samples and bioaccesible fractions, with higher levels of p-coumaric and ferulic acids after digestion, regardless of the chickpea seed. Non-commercial flours increased the presence of resveratrol and/or catechin in the bioaccessible fraction. Antioxidant action assessed in the Caco-2 cell line showed that the protective effect against reactive oxygen species (ROS) generation did not always correlate with the in vitro antioxidant capacity. Our data support that the inclusion of chickpea flours in the formulation of functional biscuits provides the consumer with products of added nutritional value with attractive organoleptic features.

Antioxidant, Anti-Inflammatory and Pro-Differentiative Effects of Chlorogenic Acid on M03-13 Human Oligodendrocyte-like Cells

Chlorogenic acid (CGA), a polyphenol found mainly in coffee and tea, exerts antioxidant, anti-inflammatory and anti-apoptotic effects at the gastrointestinal level. However, although CGA is known to cross the blood-brain barrier (BBB), its effects on the CNS are still unknown. Oligodendrocytes (OLs), the myelin-forming cells in the CNS, are the main target in demyelinating neuroinflammatory diseases such as multiple sclerosis (MS). We evaluated the antioxidant, anti-inflammatory and anti-apoptotic roles of CGA in M03-13, an immortalized human OL cell line. We found that CGA reduces intracellular superoxide ions, mitochondrial reactive oxygen species (ROS) and NADPH oxidases (NOXs) /dual oxidase 2 (DUOX2) protein levels. The stimulation of M03-13 cells with TNFα activates the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-kB) pathway, leading to an increase in superoxide ion, NOXs/DUOX2 and phosphorylated extracellular regulated protein kinase (pERK) levels. In addition, tumor necrosis factor alpha (TNF-α) stimulation induces caspase 8 activation and the cleavage of poly-ADP-ribose polymerase (PARP). All these TNFα-induced effects are reversed by CGA. Furthermore, CGA induces a blockade of proliferation, driving cells to differentiation, resulting in increased mRNA levels of myelin basic protein (MBP) and proteolipid protein (PLP), which are major markers of mature OLs. Overall, these data suggest that dietary supplementation with this polyphenol could play an important beneficial role in autoimmune neuroinflammatory diseases such as MS.

Bioactivity of Macronutrients from Chlorella in Physical Exercise

Chlorella is a marine microalga rich in proteins and containing all the essential amino acids. Chlorella also contains fiber and other polysaccharides, as well as polyunsaturated fatty acids such as linoleic acid and alpha-linolenic acid. The proportion of the different macronutrients in Chlorella can be modulated by altering the conditions in which it is cultured. The bioactivities of these macronutrients make Chlorella a good candidate food to include in regular diets or as the basis of dietary supplements in exercise-related nutrition both for recreational exercisers and professional athletes. This paper reviews current knowledge of the effects of the macronutrients in Chlorella on physical exercise, specifically their impact on performance and recovery. In general, consuming Chlorella improves both anaerobic and aerobic exercise performance as well as physical stamina and reduces fatigue. These effects seem to be related to the antioxidant, anti-inflammatory, and metabolic activity of all its macronutrients, while each component of Chlorella contributes its bioactivity via a specific action. Chlorella is an excellent dietary source of high-quality protein in the context of physical exercise, as dietary proteins increase satiety, activation of the anabolic mTOR (mammalian Target of Rapamycin) pathway in skeletal muscle, and the thermic effects of meals. Chlorella proteins also increase intramuscular free amino acid levels and enhance the ability of the muscles to utilize them during exercise. Fiber from Chlorella increases the diversity of the gut microbiota, which helps control body weight and maintain intestinal barrier integrity, and the production of short-chain fatty acids (SCFAs), which improve physical performance. Polyunsaturated fatty acids (PUFAs) from Chlorella contribute to endothelial protection and modulate the fluidity and rigidity of cell membranes, which may improve performance. Ultimately, in contrast to several other nutritional sources, the use of Chlorella to provide high-quality protein, dietary fiber, and bioactive fatty acids may also significantly contribute to a sustainable world through the fixation of carbon dioxide and a reduction of the amount of land used to produce animal feed.

Structural characterization and antinociceptive activity of polysaccharides from Anoectochilus elatus

Anoectochilus elatus is a new record species from Yunnan province in China discovered by our group in 2018, used in folk as the most popular Anoectochilus species A. roxburghii for medicinal and culinary purposes. The crude polysaccharide of Anoectochilus elatus (AEP) exhibited significant antinociceptive effects against both chemical and thermal nociception in vivo. Bio-guided isolation identified GJXL-1 as the leading analgesic polysaccharide in AEP. Detailed structural analyses rationalized GJXL-1 (molecular weight: 10.3 kDa) as an α-D-1,4-linked glucan unexpectedly branched at O-3, and O-6 position. GJXL-1 dose-dependently suppressed acetic acid-induced writhing in mice and decreased the serum levels of NO, IL-6 and TNF-α, which also repressed the licking times in both the first and second phases in formalin test. Furthermore, only L-nitroarginine partly reversed the analgesic activity of GJXL-1, indicating that GJXL-1's efficacy was partially mediated by NO regulation, possibly through inhibiting IRAK4/TAK1/NF-κB signaling pathway, and modulating gut microbiota and short-chain fatty acids production. In addition, the motor impairment and hypnotic effects of GJXL-1 were excluded. Our study suggests that GJXL-1 can be regarded as a promising and safe drug candidate for diverse pain disorders, and also a promising prebiotic candidate to maintain intestinal homeostasis and promote human gut health.

β-Glucans as Dietary Supplement to Improve Locomotion and Mitochondrial Respiration in a Model of Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular childhood disorder that causes progressive muscle weakness and degeneration. A lack of dystrophin in DMD leads to inflammatory response, autophagic dysregulation, and oxidative stress in skeletal muscle fibers that play a key role in the progression of the pathology. β-glucans can modulate immune function by modifying the phagocytic activity of immunocompetent cells, notably macrophages. Mitochondrial function is also involved in an important mechanism of the innate and adaptive immune responses, owing to high need for energy of immune cells. In the present study, the effects of 1,3-1,6 β-glucans on five-day-old non-dystrophic and dystrophic (sapje) zebrafish larvae were investigated. The effects of the sonication of β-glucans and the dechorionation of embryos were also evaluated. The results showed that the incidence of dystrophic phenotypes was reduced when dystrophic embryos were exposed to 2 and 4 mg L^-1 of 1,3-1,6 β-glucans. Moreover, when the dystrophic larvae underwent 8 mg L^-1 treatment, an improvement of the locomotor performances and mitochondrial respiration were observed. In conclusion, the observed results demonstrated that 1,3-1,6 β-glucans improve locomotor performances and mitochondrial function in dystrophic zebrafish. Therefore, for ameliorating their life quality, 1,3-1,6 β-glucans look like a promising diet supplement for DMD patients, even though further investigations are required.

Anti-Inflammatory Activity of Oat Beta-Glucans in a Crohn's Disease Model: Time- and Molar Mass-Dependent Effects

BACKGROUND

The incidence of Crohn's disease (CD) is increasing worldwide, and it has currently become a serious public health issue in society. The treatment of CD continues throughout a patient's lifetime, and therefore, it is necessary to develop new, effective treatment methods, including dietotherapy. The present study aimed to determine the effects of consumption of oat beta-glucans with different molar mass on colon inflammation (colitis) in the early stages of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced CD in an animal model.

METHODS

Sprague-Dawley rats (control and TNBS-induced CD) were divided into three dietary groups and fed for 3 days (reflecting acute inflammation) or 7 days (reflecting remission) with a feed containing 1% low (βGl) or high (βGh) molar mass oat beta-glucan or a feed without this polysaccharide. The level of colon inflammatory markers and the expression of cytokines and their receptor genes were measured by ELISA and RT-PCR methods, respectively.

RESULTS

Acute inflammation or remission (3 or 7 days after TNBS administration, respectively) stages of experimentally induced CD were characterized by an increase in the level of inflammatory markers (IL-1, IL-6, IL-10, IL-12, TNF-α, CRP, MPO, COX, and PGE2) and the disruption of some cytokine signaling pathways as well as macro- and microscopic changes of colon tissue. The consumption of oat beta-glucans reduced the level of inflammatory markers and recovered the signaling pathways and histological changes, with stronger effects of βGl after 7 days of colitis.

CONCLUSIONS

Dietary oat beta-glucans can reduce colitis at the molecular and organ level and accelerate CD remission.

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-1β, 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.

Evaluation of Polish wild Mushrooms as Beta-Glucan Sources

Mushroom beta-glucans show immunomodulatory, anticancer and antioxidant features. Numerous papers have been published in the last years on fungal polysaccharides, especially beta-glucans, demonstrating their various biological activities. However substantial data about beta-glucan contents in many mushroom species, especially wild mushrooms, are still missing. Therefore, the main objective of the study was to evaluate β-glucans in 18 species of wild mushrooms and three species of commercial mushrooms for comparison purposes. The contents of β-glucans were determined by the Megazyme method and with the Congo red method, which differ in analytical procedure. Among wild mushrooms, the highest mean β-glucan content assessed with the Megazyme method was found in Tricholoma portentosum (34.97 g/100 g DM), whereas with the Congo red method in Lactarius deliciosus (17.11 g/100 g DM) and Suillus grevillei (16.97 g/100 g DM). The β-glucans in wild mushrooms assessed with the Megazyme method were comparable to commercial mushrooms, whereas β-glucans assessed with the Congo red method were generally higher in wild mushrooms, especially in Russula vinosa, L. deliciosus and S. grevillei. This study indicates wild mushrooms as interesting material for β-glucan extraction for food industry and medicinal purposes.

Metabolism Regulation and Redox State: Insight into the Role of Superoxide Dismutase 1

Energy metabolism and redox state are strictly linked; energy metabolism is a source of reactive oxygen species (ROS) that, in turn, regulate the flux of metabolic pathways. Moreover, to assure redox homeostasis, metabolic pathways and antioxidant systems are often coordinately regulated. Several findings show that superoxide dismutase 1 (SOD1) enzyme has effects that go beyond its superoxide dismutase activity and that its functions are not limited to the intracellular compartment. Indeed, SOD1 is secreted through unconventional secretory pathways, carries out paracrine functions and circulates in the blood bound to lipoproteins. Striking experimental evidence links SOD1 to the redox regulation of metabolism. Important clues are provided by the systemic effects on energy metabolism observed in mutant SOD1-mediated amyotrophic lateral sclerosis (ALS). The purpose of this review is to analyze in detail the involvement of SOD1 in redox regulation of metabolism, nutrient sensing, cholesterol metabolism and regulation of mitochondrial respiration. The scientific literature on the relationship between ALS, mutated SOD1 and metabolism will also be explored, in order to highlight the metabolic functions of SOD1 whose biological role still presents numerous unexplored aspects that deserve further investigation.