Publishing type：Research paper (scientific journal)   International / domestic magazine：International journal  

OBJECTIVE: Food addiction is a multifactorial disorder characterised by a loss of control over food intake that may promote obesity and alter gut microbiota composition. We have investigated the potential involvement of the gut microbiota in the mechanisms underlying food addiction. DESIGN: We used the Yale Food Addiction Scale (YFAS) 2.0 criteria to classify extreme food addiction in mouse and human subpopulations to identify gut microbiota signatures associated with vulnerability to this disorder. RESULTS: Both animal and human cohorts showed important similarities in the gut microbiota signatures linked to food addiction. The signatures suggested possible non-beneficial effects of bacteria belonging to the Proteobacteria phylum and potential protective effects of Actinobacteria against the development of food addiction in both cohorts of humans and mice. A decreased relative abundance of the species Blautia wexlerae was observed in addicted humans and of Blautia genus in addicted mice. Administration of the non-digestible carbohydrates, lactulose and rhamnose, known to favour Blautia growth, led to increased relative abundance of Blautia in mice faeces in parallel with dramatic improvements in food addiction. A similar improvement was revealed after oral administration of Blautia wexlerae as a beneficial microbe. CONCLUSION: By understanding the crosstalk between this behavioural alteration and gut microbiota, these findings constitute a step forward to future treatments for food addiction and related eating disorders.

DOI： 10.1136/gutjnl-2023-331445

PubMed

Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.celrep.2024.114752

Authorship：Lead author   Publishing type：Research paper (scientific journal)  

Introduction

Campylobacter spp. are a public health concern, yet there is still no effective vaccine or medicine available.

Methods

Here, we developed a Campylobacter jejuni-specific antibody and found that it targeted a menaquinol cytochrome c reductase complex QcrC.

Results

The antibody was specifically reactive to multiple C. jejuni strains including clinical isolates from patients with acute enteritis and was found to inhibit the energy metabolism and growth of C. jejuni. Different culture conditions produced different expression levels of QcrC in C. jejuni, and these levels were closely related not only to the energy metabolism of C. jejuni but also its pathogenicity. Furthermore, immunization of mice with recombinant QcrC induced protective immunity against C. jejuni infection.

Discussion

Taken together, our present findings highlight a possible antibody- or vaccination-based strategy to prevent or control Campylobacter infection by targeting the QcrC-mediated metabolic pathway.

DOI： 10.3389/fmicb.2024.1415893

PubMed

Publishing type：Research paper (scientific journal)  

Abstract

This study investigated the effects of white meat, such as chicken, intake combined with resistance training on muscle mass and strength in the elderly women, and whether the underlying mechanism involves changes in the gut microbiota. Ninety‐three volunteers (age 59–79 years) were randomly allocated to sedentary control with placebo (Sed + PL) or chicken meat (Sed + HP) and resistance training with placebo (RT + PL) or chicken meat (RT + HP). Resistance training sessions were performed 3 d/week for 12 weeks using leg extensions and curls. Boiled chicken meat (110 g, containing 22.5 g protein) was ingested 3 d/week for 12 weeks. Maximal muscle strength and whole‐body lean mass increased significantly in the RT + PL group compared to the Sed + HP group, and the RT + HP group showed a significantly greater increase than the Sed + HP and RT + PL groups. Additionally, the gut microbiota composition did not change before or after the interventions in any of the four groups. Moreover, the individual comparison of gut bacteria using false discovery rate‐based statistical analysis showed no alterations before or after the interventions in the four groups. Resistance training combined with chicken meat intake may effective have increased muscle mass and strength without drastically modifying the gut microbiota composition in elderly women.

DOI： 10.14814/phy2.16100

Publishing type：Research paper (scientific journal)  

Intestinal bacteria metabolize dietary substances to produce bioactive postbiotics, among which some are recognized for their role in promoting host health. We here explored the postbiotic potential of two omega-3 α-linolenic acid–derived metabolites: trans-10-cis-15-octadecadienoic acid (t10,c15-18:2) and cis-9-cis-15-octadecadienoic acid (c9,c15-18:2). Dietary intake of lipids rich in omega-3 α-linolenic acid elevated levels of t10,c15-18:2 and c9,c15-18:2 in the serum and feces of mice, an effect dependent on the presence of intestinal bacteria. Notably, t10,c15-18:2 mitigated skin inflammation in mice that became hypersensitive after exposure to 2,4-dinitrofluorobenzene, an experimental model for allergic contact dermatitis. In particular, t10,c15-18:2—but not c9,c15-18:2—attenuated ear swelling and edema, characteristic symptoms of contact hypersensitivity. The anti-inflammatory effects of t10,c15-18:2 were due to its ability to suppress the release of vascular endothelial growth factor A from keratinocytes, thereby mitigating the enhanced vascular permeability induced by hapten stimulation. Our study identified retinoid X receptor as a functional receptor that mediates the downregulation of skin inflammation upon treatment with t10,c15-18:2. Our results suggest that t10,c15-18:2 holds promise as an omega-3 fatty acid–derived postbiotic with potential therapeutic implications for alleviating the skin edema seen in allergic contact dermatitis–induced inflammation.

DOI： 10.3389/fcimb.2024.1355679

Publishing type：Research paper (scientific journal)   International / domestic magazine：International journal  

Despite accumulating evidence that suggests a unique gut microbiota composition in athletes, a comprehensive understanding of this phenomenon is lacking. Furthermore, seasonal variation in the gut microbiota of athletes, particularly during the off-season, remains underexplored. This study aimed to compare the gut microbiotas between athletic subjects (AS) and non-athletic subjects (NS), and to investigate variations between athletic and off-season periods. The data were derived from an observational study involving Japanese male handball players. The results revealed a distinct gut microbiota composition in AS compared with NS, characterized by significantly higher alpha-diversity and a greater relative abundance of Faecalibacterium and Streptococcus. Moreover, a comparative analysis between athletic and off-season periods in AS demonstrated a significant change in alpha-diversity. Notably, AS exhibited significantly higher alpha-diversity than NS during the athletic season, but no significant difference was observed during the off-season. This study demonstrates the characteristics of the gut microbiota of Japanese handball players and highlights the potential for changes in alpha-diversity during the off-season. These findings contribute to our understanding of the dynamic nature of the gut microbiota of athletes throughout the season.

DOI： 10.3390/microorganisms12040781

PubMed

Publishing type：Research paper (scientific journal)   International / domestic magazine：International journal  

Lipopolysaccharide (LPS), a cell surface component of Gram-negative bacteria, activates innate immunity. Its active principle is the terminal glycolipid lipid A. Acetobacter pasteurianus is a Gram-negative bacterium used in the fermentation of traditional Japanese black rice vinegar (kurozu). In this study, we focused on A. pasteurianus lipid A, which is a potential immunostimulatory component of kurozu. The active principle structure of A. pasteurianus lipid A has not yet been identified. Herein, we first systematically synthesized three types of A. pasteurianus lipid As containing a common and unique tetrasaccharide backbone. We developed an efficient method for constructing the 2-trehalosamine skeleton utilizing borinic acid-catalyzed glycosylation to afford 1,1'-α,α-glycoside in high yield and stereoselectivity. A common tetrasaccharide intermediate with an orthogonal protecting group pattern was constructed via [2+2] glycosylation. After introducing various fatty acids, all protecting groups were removed to achieve the first chemical synthesis of three distinct types of A. pasteurianus lipid As. After evaluating their immunological function using both human and murine cell lines, we identified the active principles of A. pasteurianus LPS. We also found the unique anomeric structure of A. pasteurianus lipid A contributes to its high chemical stability.

DOI： 10.1002/anie.202402922

PubMed

マウスへの経鼻投与におけるアルカリゲネス属リピドA(ALA)とモノホスホリルリピドA(MPLA)のアジュバント活性を比較し、これらの効果の根底にあるメカニズムを調べた。ALAは化学的合成品を用いた。マウスの鼻腔にオボアルブミン(OVA)とALA/MPLAを投与した後、血清、鼻洗浄液、気管支肺胞洗浄液中のOVA特異的IgAとIgGをELISAで測定した。皮下投与については血清中の抗体を測定した。経鼻および皮下投与後、ALAはMPLAより高レベルの抗原特異的抗体分泌を誘導した。特に、ALAは経鼻ワクチン接種において優れた効果を発揮した。鼻腔内と全身のIgA産生に及ぼす効果と一致して、ALAは鼻咽頭関連リンパ組織(NALT)と頸部リンパ節(CLN)内の胚中心(GC)の形成を促進し、GC B細胞、IgA陽性B細胞、Tfh細胞集団を増加させた。経鼻ワクチンにおけるALAの優位性の根底にある可能性の高いメカニズムとしては、ALAが鼻腔組織における高度に活性化されたCD11b陽性の従来型2型樹状細胞(cDC2)の浸潤、特にcDC2A細胞数を増加させることが考えられた。さらに、ALAは鼻腔組織の間質細胞上のGM-CSFとCCL2の発現とCD45陽性免疫細胞上のCCL3とCCL4の発現を誘導した。これらのケモカインのうちCCL2とCCL3は鼻腔組織へのcDC2の動員を支援した。

日本の一般成人の骨格筋機能、量、質と関連する腸内細菌属を同定するため横断研究を実施した。都市在住の35-80歳の成人164例の糞便検体を収集し、16S rRNAアンプリコンシーケンス解析を行った。その結果、60歳以上の患者においてのみBacteroidesおよびPrevotella 9が脚伸展筋力(LEP)と有意に関連していた。BacteroidesとPrevotella 9の両方を同じ回帰モデルに含めた場合、Bacteroidesのみが有意にLEPと関連した。なお、骨格筋量、握力、位相角と、主要な腸内細菌属との間に有意な関連はみられなかった。以上より、日本の高齢者ではBacteroidesとLEPとの間に有意な正の関係が認められた。