Effect of Rotavirus Infection and 2′-Fucosyllactose Administration on Rat Intestinal Gene Expression

Viral infections are described as modifying host gene expression; however, there is limited insight regarding rotavirus (RV) infections. This study aimed to assess the changes in intestinal gene expression after RV infection in a preclinical model, and the effect of 2-fucosyllactose (2′-FL) on this process. From days 2 to 8 of life, rats were supplemented with the dietary oligosaccharide 2′-FL or vehicle. In addition, an RV was inoculated on day 5 to nonsupplemented animals (RV group) and to 2′-FL-fed animals (RV+2′-FL group). Incidence and severity of diarrhea were established. A portion from the middle part of the small intestine was excised for gene expression analysis by microarray kit and qPCR. In nonsupplemented animals, RV-induced diarrhea upregulated host antiviral genes (e.g., Oas1a, Irf7, Ifi44, Isg15) and downregulated several genes involved in absorptive processes and intestinal maturation (e.g., Onecut2, and Ccl19). The 2′-FL-supplemented and infected animals had less diarrhea; however, their gene expression was affected in a similar way as the control-infected animals, with the exception of some immunity/maturation markers that were differentially expressed (e.g., Ccl12 and Afp). Overall, assessing the expression of these key genes may be useful in the evaluation of the efficacy of nutritional interventions or treatments for RV infection

Impact of maternal Bifidobacterium breve M-16V and scGOS/lcFOS supplementation during pregnancy and lactation on the maternal immune system and milk composition

IntroductionMaternal synbiotic supplementation during pregnancy and lactation can significantly influence the immune system. Prebiotics and probiotics have a positive impact on the immune system by preventing or ameliorating among others intestinal disorders. This study focused on the immunomodulatory effects of B. breve M-16V and short chain galacto-oligosaccharides (scGOS)/long chain fructo-oligosachairdes (lcFOS), including systemic and mucosal compartments and milk composition. MethodsLewis rats were orally administered with the synbiotic or vehicle during pregnancy (21 days) and lactation (21 days). At the weaning day, small intestine (SI), mammary gland (MG), adipose tissue, milk, mesenteric lymph nodes (MLN), salivary gland (SG), feces and cecal content were collected from the mothers.ResultsThe immunoglobulinome profile showed increased IgG2c in plasma and milk, as well as elevated sIgA in feces at weaning. The supplementation improved lipid metabolism through enhanced brown adipose tissue activity and reinforced the intestinal barrier by increasing the expression of Muc3, Cldn4, and Ocln. The higher production of short chain fatty acids in the cecum and increased Bifidobacterium counts suggest a potential positive impact on the gastrointestinal tract. DiscussionThese findings indicate that maternal synbiotic supplementation during gestation and lactation improves their immunological status and improved milk composition

Impact of maternal Bifidobacterium breve M-16V and scGOS/lcFOS supplementation during pregnancy and lactation on the maternal immune system and milk composition

Introduction: Maternal synbiotic supplementation during pregnancy and lactation can significantly influence the immune system. Prebiotics and probiotics have a positive impact on the immune system by preventing or ameliorating among others intestinal disorders. This study focused on the immunomodulatory effects of B. breve M-16V and short chain galacto-oligosaccharides (scGOS)/long chain fructo-oligosachairdes (lcFOS), including systemic and mucosal compartments and milk composition. Methods: Lewis rats were orally administered with the synbiotic or vehicle during pregnancy (21 days) and lactation (21 days). At the weaning day, small intestine (SI), mammary gland (MG), adipose tissue, milk, mesenteric lymph nodes (MLN), salivary gland (SG), feces and cecal content were collected from the mothers. Results: The immunoglobulinome profile showed increased IgG2c in plasma and milk, as well as elevated sIgA in feces at weaning. The supplementation improved lipid metabolism through enhanced brown adipose tissue activity and reinforced the intestinal barrier by increasing the expression of Muc3, Cldn4, and Ocln. The higher production of short chain fatty acids in the cecum and increased Bifidobacterium counts suggest a potential positive impact on the gastrointestinal tract. Discussion: These findings indicate that maternal synbiotic supplementation during gestation and lactation improves their immunological status and improved milk composition.The research described in this paper was supported by La Marató-TV3 (DIM-2-ELI, ref. 2018–27/30–31). LS-F holds a fellowship from the Generalitat de Catalunya, FI-SDUR (2023 FISDU 00035). The INSA-UB acknowledge the Maria de Maeztu Unit of Excellence (Grant CEX2021–001234-M) funded by MICIN/AEI/FEDER, UE. The IATA-CSIC authors also acknowledge the Spanish government MCIN/AEI to the Center of Excellence Accreditation Severo Ochoa (CEX2021–001189-S/MCIN/AEI/10.13039/501100011033).With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2021-001189-S and CEX2021-001234-M)Peer reviewe

Genomic Characterization of Host Factors Related to SARS-CoV-2 Infection in People with Dementia and Control Populations: The GR@ACE/DEGESCO Study

Emerging studies have suggested several chromosomal regions as potential host genetic factors involved in the susceptibility to SARS-CoV-2 infection and disease outcome. We nested a COVID-19 genome-wide association study using the GR@ACE/DEGESCO study, searching for susceptibility factors associated with COVID-19 disease. To this end, we compared 221 COVID-19 confirmed cases with 17,035 individuals in whom the COVID-19 disease status was unknown. Then, we performed a meta-analysis with the publicly available data from the COVID-19 Host Genetics Initiative. Because the APOE locus has been suggested as a potential modifier of COVID-19 disease, we added sensitivity analyses stratifying by dementia status or by disease severity. We confirmed the existence of the 3p21.31 region (LZTFL1, SLC6A20) implicated in the susceptibility to SARS-CoV-2 infection and TYK2 gene might be involved in COVID-19 severity. Nevertheless, no statistically significant association was observed in the COVID-19 fatal outcome or in the stratified analyses (dementia-only and non-dementia strata) for the APOE locus not supporting its involvement in SARS-CoV-2 pathobiology or COVID-19 prognosis

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

Effect of Rotavirus Infection and 2′-Fucosyllactose Administration on Rat Intestinal Gene Expression

Viral infections are described as modifying host gene expression; however, there is limited insight regarding rotavirus (RV) infections. This study aimed to assess the changes in intestinal gene expression after RV infection in a preclinical model, and the effect of 2-fucosyllactose (2′-FL) on this process. From days 2 to 8 of life, rats were supplemented with the dietary oligosaccharide 2′-FL or vehicle. In addition, an RV was inoculated on day 5 to nonsupplemented animals (RV group) and to 2′-FL-fed animals (RV+2′-FL group). Incidence and severity of diarrhea were established. A portion from the middle part of the small intestine was excised for gene expression analysis by microarray kit and qPCR. In nonsupplemented animals, RV-induced diarrhea upregulated host antiviral genes (e.g., Oas1a, Irf7, Ifi44, Isg15) and downregulated several genes involved in absorptive processes and intestinal maturation (e.g., Onecut2, and Ccl19). The 2′-FL-supplemented and infected animals had less diarrhea; however, their gene expression was affected in a similar way as the control-infected animals, with the exception of some immunity/maturation markers that were differentially expressed (e.g., Ccl12 and Afp). Overall, assessing the expression of these key genes may be useful in the evaluation of the efficacy of nutritional interventions or treatments for RV infection

Maternal Synbiotic Supplementation with <i>B. breve</i> M-16V and scGOS/lcFOS Shape Offspring Immune Development and Gut Microbiota at the End of Suckling

Immune system development during gestation and suckling is significantly modulated by maternal environmental and dietary factors. Breastfeeding is widely recognized as the optimal source of nutrition for infant growth and immune maturation, and its composition can be modulated by the maternal diet. In the present work, we investigated whether oral supplementation with Bifidobacterium breve M-16V and short-chain galacto-oligosaccharide (scGOS) and long-chain fructo-oligosaccharide (lcFOS) to rat dams during gestation and lactation has an impact on the immune system and microbiota composition of the offspring at day 21 of life. On that day, blood, adipose tissue, small intestine (SI), mesenteric lymph nodes (MLN), salivary gland (SG), cecum, and spleen were collected. Synbiotic supplementation did not affect the overall body or organ growth of the pups. The gene expression of Tlr9, Muc2, IgA, and Blimp1 were upregulated in the SI, and the increase in IgA gene expression was further confirmed at the protein level in the gut wash. Synbiotic supplementation also positively impacted the microbiota composition in both the small and large intestines, resulting in higher proportions of Bifidobacterium genus, among others. In addition, there was an increase in butanoic, isobutanoic, and acetic acid concentrations in the cecum but a reduction in the small intestine. At the systemic level, synbiotic supplementation resulted in higher levels of immunoglobulin IgG2c in plasma, SG, and MLN, but it did not modify the main lymphocyte subsets in the spleen and MLN. Overall, synbiotic maternal supplementation is able to positively influence the immune system development and microbiota of the suckling offspring, particularly at the gastrointestinal level