Aberrant plasma protein glycosylation is associated with a wide range of diseases, including diabetes, cardiovascular, and immunological disorders. To investigate plasma protein glycosylation ...alterations due to weight loss and successive weight-maintenance diets, 1850 glycomes from participants of the Diogenes study were analyzed using Ultra-High-Performance Liquid Chromatography (UHPLC). The Diogenes study is a large dietary intervention study in which participants were subjected to a low-calorie diet (LCD) followed by one of five different weight-maintenance diets in a period of 6 months. The most notable alterations of the plasma glycome were 8 weeks after the subjects engaged in the LCD; a significant increase in low-branched glycan structures, accompanied by a decrease in high-branched glycan structures. After the LCD period, there was also a significant rise in N-glycan structures with antennary fucose. Interestingly, we did not observe significant changes between different diets, and almost all effects we observed immediately after the LCD period were annulled during the weight-maintenance diets period.
Obesity-induced inflammation activates the adaptive immune system by altering immunoglobulin G (IgG) glycosylation in a way to produce more proinflammatory antibodies. The IgG glycome has already ...been well studied, and its alterations are correlated with a high body mass index (BMI) and central adiposity. Still, the IgG N-glycome susceptibility to different dietary regimes for weight control after the initial weight loss has not been studied. To explore changes in IgG glycosylation induced by weight loss and subsequent weight-maintenance diets, we analyzed 1,850 IgG glycomes from subjects in a dietary intervention Diogenes study. In this study, participants followed a low-calorie diet (LCD) providing 800 kcal/d for 8 weeks, followed by one of five weight-maintenance diets over a 6-month period. The most significant alteration of the IgG N-glycome was present 8 weeks after the subjects underwent an LCD, a statistically significant decrease of agalactosylated and the increase of sialylated N glycans. In the follow-up period, the increase in glycans with bisecting GlcNAc and the decrease in sialylated glycans were observed. Those changes were present regardless of the diet type, and we did not observe significant changes between different diets. However, it should be noted that in all five diet groups, there were individuals who prominently altered their IgG glycome composition in either proinflammatory or anti-inflammatory directions.
Glycans are an essential structural component of immunoglobulin G (IgG) that modulate its structure and function. However, regulatory mechanisms behind this complex posttranslational modification are ...not well known. Previous genome-wide association studies (GWAS) identified 29 genomic regions involved in regulation of IgG glycosylation, but only a few were functionally validated. One of the key functional features of IgG glycosylation is the addition of galactose (galactosylation), a trait which was shown to be associated with ageing. We performed GWAS of IgG galactosylation (N=13,705) and identified 16 significantly associated loci, indicating that IgG galactosylation is regulated by a complex network of genes that extends beyond the galactosyltransferase enzyme that adds galactose to IgG glycans. Gene prioritization identified 37 candidate genes. Using a recently developed CRISPR/dCas9 system we manipulated gene expression of candidate genes in the
IgG expression system. Upregulation of three genes,
and
, changed the IgG glycome composition, which confirmed that these three genes are involved in IgG galactosylation in this
expression system.
Abstract Ageing is a complex biological process with variations among individuals, leading to the development of ageing clocks to estimate biological age. Glycans, particularly in immunoglobulin G ...(IgG), have emerged as potential biomarkers of ageing, with changes in glycosylation patterns correlating with chronological age. For precision analysis, three different plasma pools were analysed over 26 days in tetraplicates, 312 samples in total. In short-term variability analysis, two cohorts were analysed: AstraZeneca MFO cohort of 26 healthy individuals (median age 20) and a cohort of 70 premenopausal Chinese women (median age 22.5) cohort monitored over 3 months. Long-term variability analysis involved two adult men aged 47 and 57, monitored for 5 and 10 years, respectively. Samples were collected every 3 months and 3 weeks, respectively. IgG N -glycan analysis followed a standardized approach by isolating IgG, its subsequent denaturation and deglycosylation followed by glycan cleanup and labelling. Capillary gel electrophoresis with laser-induced fluorescence (CGE-LIF) and ultra-performance liquid chromatography analyses were employed for glycan profiling. Statistical analysis involved normalization, batch correction, and linear mixed models to assess time effects on derived glycan traits. The intermediate precision results consistently exhibited very low coefficient of variation values across all three test samples. This consistent pattern underscores the high level of precision inherent in the CGE method for analysing the glycan clock of ageing. The AstraZeneca MFO cohort did not show any statistically significant trends, whereas the menstrual cycle cohort exhibited statistically significant trends in digalactosylated (G2), agalactosylated (G0) and fucosylation (F). These trends were attributed to the effects of the menstrual cycle. Long-term stability analysis identified enduring age-related trends in both subjects, showing a positive time effect in G0 and bisected N -acetylglucosamine, as well as a negative time effect in G2 and sialylation, aligning with earlier findings. Time effects measured for monogalactosylation, and F remained substantially lower than ones observed for other traits. The study found that IgG N -glycome analysis using CGE-LIF exhibited remarkably high intermediate precision. Moreover, the study highlights the short- and long-term stability of IgG glycome composition, coupled with a notable capacity to adapt and respond to physiological changes and environmental influences such as hormonal changes, disease, and interventions. The discoveries from this study propel personalized medicine forward by deepening our understanding of how IgG glycome relates to age-related health concerns. This study underscores the reliability of glycans as a biomarker for tracking age-related changes and individual health paths.
Particulate β-glucans were isolated from brewer's yeast using three different procedures--alkaline (A), alkaline-acidic (AA) and alkaline-acidic with mannoprotein removal (AAM) and dried using three ...different methods--air drying (AD), lyophilization (L) and spray drying (SD). In this work, the obtained β-glucan preparations were tested for their microstructure, rheological properties, swelling, water-holding and oil-binding capacities. According to their rheological properties, suspensions containing 1 and 2% (by mass) of spray-dried samples belong to the category of dilatant fluids. Among the spray-dried samples, rheological behaviour and water-holding capacity of the preparation AA-SD differed from those obtained by other two procedures (A-SD and AAM-SD). Concerning different drying methods applied, swelling was the lowest in the lyophilized samples and the most pronounced in the air-dried ones. Oil-binding capacity was the highest in the lyophilized preparations and increased proportionally to the number of processing steps applied in the isolation procedure. Key words: brewer's yeast, oil-binding capacity, particulate β-glucan, rheology, swelling, water-holding capacity
Particulate β-glucans were isolated from brewer's yeast using three different procedures - alkaline (A), alkaline-acidic (AA) and alkaline-acidic with mannoprotein removal (AAM) and dried using three ...different methods - air drying (AD), lyophilization (L) and spray drying (SD). In this work, the obtained β-glucan preparations were tested for their microstructure, rheological properties, swelling, water-holding and oil-binding capacities. According to their rheological properties, suspensions containing 1 and 2 % (by mass) of spray-dried samples belong to the category of dilatant fluids. Among the spray-dried samples, rheological behaviour and water-holding capacity of the preparation AA-SD differed from those obtained by other two procedures (A-SD and AAM-SD). Concerning different drying methods applied, swelling was the lowest in the lyophilized samples and the most pronounced in the air-dried ones. Oil-binding capacity was the highest in the lyophilized preparations and increased proportionally to the number of processing steps applied in the isolation procedure. PUBLICATION ABSTRACT
Netopljivi β-glukani izolirani su iz pivskog kvasca različitim postupcima – alkalnim (A), alkalno-kiselinskim (AK) i alkalno-kiselinskim s uklanjanjem manoproteina (AKM) te osušeni trima različitim ...metodama – sušenjem na zraku, liofilizacijom i sušenjem raspršivanjem. U pripravcima β-glukana ispitani su: mikrostruktura, reološka svojstva, bubrenje te sposobnost vezanja vode ili ulja. Prema njihovim reološkim svojstvima suspenzije koje su sadržavale 1 i 2 % (masenih udjela) uzoraka osušenih raspršivanjem pripadaju u kategoriju dilatantnih tekućina. Reološka svojstva i sposobnost vezanja vode AK uzorka osušenog raspršivanjem razlikovali su se od ostalih uzoraka osušenih istom metodom, a izoliranih A i AKM postupcima. S obzirom na različite metode sušenja, bubrenje je bilo najslabije u liofiliziranim uzrocima, a najjače u uzorcima osušenim na zraku. Sposobnost vezanja ulja najizraženija je u liofiliziranim pripravcima, a povećavala se proporcionalno tijekom izolacije.
Water-insoluble (particulate) β-glucan was isolated from the cell walls of spent brewer’s yeast using a single-step alkaline treatment. To stabilize β-glucan water suspensions, sonication was ...successfully applied. Three different drying methods were used: air-drying, lyophilization and spray-drying. Air-drying and lyophilization caused β-glucan particles agglomeration and changes of their microstructure. Sonication combined with spray-drying resulted in minimal β-glucan structural changes and negligible formation of agglomerates. Reaggregation of spray-dried β-glucan particles was minimal even after resuspending in water.
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