Oral-Nasopharyngeal Dendritic Cells Mediate T Cell-Independent IgA Class Switching on B-1 B Cells

Native cholera toxin (nCT) as a nasal adjuvant was shown to elicit increased levels of T-independent S-IgA antibody (Ab) responses through IL-5- IL-5 receptor interactions between CD4+ T cells and IgA+ B-1 B cells in murine submandibular glands (SMGs) and nasal passages (NPs). Here, we further investigate whether oral-nasopharyngeal dendritic cells (DCs) play a central role in the induction of B-1 B cell IgA class switch recombination (CSR) for the enhancement of T cell-independent (TI) mucosal S-IgA Ab responses. High expression levels of activation-induced cytidine deaminase, Iα-Cμ circulation transcripts and Iμ-Cα transcripts were seen on B-1 B cells purified from SMGs and NPs of both TCRβ−/− mice and wild-type mice given nasal trinitrophenyl (TNP)-LPS plus nCT, than in the same tissues of mice given nCT or TNP-LPS alone. Further, DCs from SMGs, NPs and NALT of mice given nasal TNP-LPS plus nCT expressed significantly higher levels of a proliferation-inducing ligand (APRIL) than those in mice given TNP-LPS or nCT alone, whereas the B-1 B cells in SMGs and NPs showed elevated levels of transmembrane activator and calcium modulator cyclophilin ligand interactor (TACI) expression. Interestingly, high frequencies of IgA+ B-1 B cells were induced when peritoneal IgA− IgM+ B cells were stimulated with mucosal DCs from mice given nasal TNP-LPS plus nCT. Taken together, these findings show that nasal nCT plays a key role in the enhancement of mucosal DC-mediated TI IgA CSR by B-1 B cells through their interactions with APRIL and TACI

Collection of Macaca fascicularis cDNAs derived from bone marrow, kidney, liver, pancreas, spleen, and thymus

<p>Abstract</p> <p>Background</p> <p>Consolidating transcriptome data of non-human primates is essential to annotate primate genome sequences, and will facilitate research using non-human primates in the genomic era. <it>Macaca fascicularis </it>is a macaque monkey that is commonly used for biomedical and ecological research.</p> <p>Findings</p> <p>We constructed cDNA libraries of <it>Macaca fascicularis</it>, derived from tissues obtained from bone marrow, liver, pancreas, spleen, and thymus of a young male, and kidney of a young female. In total, 5'-end sequences of 56,856 clones were determined. Including the previously established cDNA libraries from brain and testis, we have isolated 112,587 cDNAs of <it>Macaca fascicularis</it>, which correspond to 56% of the curated human reference genes.</p> <p>Conclusion</p> <p>These sequences were deposited in the public sequence database as well as in-house macaque genome database <url>http://genebank.nibio.go.jp/qfbase/</url>. These data will become valuable resources for identifying functional parts of the genome of macaque monkeys in future studies.</p

Prevention of Disuse Muscle Atrophy by Dietary Ingestion of 8-Prenylnaringenin in Denervated Mice

Flavonoids have attracted considerable attention in relation to their effects upon health. 8-Prenylnaringenin (8-PN) is found in the common hop (Humulus lupulus) and assumed to be responsible for the health impact of beer consumption. We wanted to clarify the effects of prenylation on the physiological functions of dietary flavonoids by comparing the effects of 8-PN with that of intact naringenin in the prevention of disuse muscle atrophy using a model of denervation in mice. Consumption of 8-PN (but not naringenin) prevented loss of weight in the gastrocnemius muscle further supported by the lack of induction of the protein content of a key ubiquitin ligase involved in muscle atrophy, atrogin-1, and by the activation of Akt phosphorylation. 8-PN content in the gastrocnemius muscle was tenfold higher than that of naringenin. These results suggested that, compared with naringenin, 8-PN was effectively concentrated into skeletal muscle to exert its preventive effects upon disuse muscle atrophy. It is likely that prenylation generates novel functions for 8-PN by enhancing its accumulation into muscle tissue through dietary intake

Bioavailability of prenyl quercetin

Prenyl flavonoids are widely distributed in plant foods and have attracted appreciable attention in relation to their potential benefits for human health. Prenylation may enhance the biological functions of flavonoids by introducing hydrophobic properties in their basic structures. Previously, we found that 8-prenyl naringenin exerted a greater preventive effect on muscle atrophy than nonprenylated naringenin in a mouse model. Here, we aimed to estimate the effect of prenylation on the bioavailability of dietary quercetin (Q). The cellular uptake of 8-prenyl quercetin (PQ) and Q in Caco-2 cells and C2C12 myotube cells was examined. Prenylation significantly enhanced the cellular uptake by increasing the lipophilicity in both cell types. In Caco-2 cells, efflux of PQ to the basolateral side was <15% of that of Q, suggesting that prenylation attenuates transport from the intestine to the circulation. After intragastric administration of PQ or Q to mice or rats, the area under the concentration-time curve for PQ in plasma and lymph was 52.5% and 37.5% lower than that of Q, respectively. PQ and its O-methylated form (MePQ) accumulated at much higher amounts than Q and O-methylated Q in the liver (Q: 3400%; MePQ: 7570%) and kidney (Q: 385%; MePQ: 736%) of mice after 18 d of feeding. These data suggest that prenylation enhances the accumulation of Q in tissues during long-term feeding, even though prenylation per se lowers its intestinal absorption from the diet

Stress control and human nutrition

Stress is a pervasive factor in everyday life that critically affects development and functioning. Severe and prolonged stress exposure impairs homeostatic mechanisms, particularly associated with the onset of depressive illness. Brain food is aimed at preventing as well as treating a growing number of stress-related mental disorders. Some topics on the association of stress and nutrition is reviewed. (1) An increased activity of serotonergic neurons in the brain is an established consequence of stress. An increase in brain tryptophan levels on the order of that produced by eating a carbohydrate-rich/protein-poor meal causes parallel increases in the amounts of serotonin released into synapses. (2) Eating is thought to be suppressed during stress, due to anorectic effects of corticotrophin releasing hormone, and increased during recovery from stress, due to appetite stimulating effects of residual cortisol. (3) A strong inverse association between coffee intake and risk of suicide. (4) Night eating syndrome has been found to occur during periods of stress and is associated with poor results at attempts to lose weight and disturbances in the hypothalamic-pituitaryadrenal axis. (5) Dietary antioxidants present in fruits and vegetables may improve cognitive function. Therefore, it is concluded that the establishment of functional foods that correctly regulate stress response must be firmly based upon scientific knowledge and legal regulation

Effects of forced swimming stress on rat brain function

Chronic stress has been reported to be an essential factor for depression. In this study, the effect of forced swimming stress on neurotransmitters and cellular signaling pathway contributing to brain functions was investigated using the forced swimming test (FST) in order to understanding of mechanisms to regulate stress signals in brain. Antidepressant drug, imipramine, significantly reduced the immobility time of male rats in the FST by 85% at a dose of 15mg/kg for 2 weeks. This result indicated that the swimming stress caused a depressed state in the rats without administration of imipramine. Swimming stress significantly lowered the serotonergic ratio and also markedly enhanced the phosphorylation of ERK1/2 in the hypothalamus region compared to the rats without FST. These phenomena maybe included in key mechanisms of the development of depression

Combined landscape of single-nucleotide variants and copy number alterations in clonal hematopoiesis

クローン性造血の臨床予後への影響を解明 --遺伝子変異とコピー数異常の統合的な知見--. 京都大学プレスリリース. 2021-07-09.Clonal hematopoiesis (CH) in apparently healthy individuals is implicated in the development of hematological malignancies (HM) and cardiovascular diseases. Previous studies of CH analyzed either single-nucleotide variants and indels (SNVs/indels) or copy number alterations (CNAs), but not both. Here, using a combination of targeted sequencing of 23 CH-related genes and array-based CNA detection of blood-derived DNA, we have delineated the landscape of CH-related SNVs/indels and CNAs in 11, 234 individuals without HM from the BioBank Japan cohort, including 672 individuals with subsequent HM development, and studied the effects of these somatic alterations on mortality from HM and cardiovascular disease, as well as on hematological and cardiovascular phenotypes. The total number of both types of CH-related lesions and their clone size positively correlated with blood count abnormalities and mortality from HM. CH-related SNVs/indels and CNAs exhibited statistically significant co-occurrence in the same individuals. In particular, co-occurrence of SNVs/indels and CNAs affecting DNMT3A, TET2, JAK2 and TP53 resulted in biallelic alterations of these genes and was associated with higher HM mortality. Co-occurrence of SNVs/indels and CNAs also modulated risks for cardiovascular mortality. These findings highlight the importance of detecting both SNVs/indels and CNAs in the evaluation of CH