RESUMO
Microorganisms exist in large communities of diverse species, exhibiting various functionalities. The mammalian gut microbiome, for instance, has the functionality of digesting dietary fibre and producing different short-chain fatty acids. Not all microbes present in a community contribute to a given functionality; it is possible to find a minimal microbiome, which is a subset of the large microbiome, that is capable of performing the functionality while maintaining other community properties such as growth rate and metabolite production. Such a minimal microbiome will also contain keystone species for SCFA production in that community. In this work, we present a systematic constraint-based approach to identify a minimal microbiome from a large community for a user-proposed function. We employ a top-down approach with sequential deletion followed by solving a mixed-integer linear programming problem with the objective of minimising the L1-norm of the membership vector. Notably, we consider quantitative measures of community growth rate and metabolite production rates. We demonstrate the utility of our algorithm by identifying the minimal microbiomes corresponding to three model communities of the gut, and discuss their validity based on the presence of the keystone species in the community. Our approach is generic, flexible and finds application in studying a variety of microbial communities. The algorithm is available from https://github.com/RamanLab/minMicrobiome .
Assuntos
Algoritmos, Microbiota, Microbiota/genética, Microbiota/fisiologia, Microbioma Gastrointestinal/genética, Microbioma Gastrointestinal/fisiologia, Humanos, Ácidos Graxos Voláteis/metabolismo, Animais, Modelos Biológicos, Bactérias/genéticaRESUMO
This study is aimed at assessing the impact of soluble dietary fiber inulin on the treatment of diabetes-related chronic inflammation and kidney injury in mice with type 2 diabetes (T2DM). The T2DM model was created by feeding the Institute of Cancer Research (ICR) mice a high-fat diet and intraperitoneally injecting them with streptozotocin (50 mg/kg for 5 consecutive days). The thirty-six ICR mice were divided into three dietary groups: the normal control (NC) group, the T2DM (DM) group, and the DM + inulin diet (INU) group. The INU group mice were given inulin at the dose of 500 mg/kg gavage daily until the end of the 12th week. After 12 weeks, the administration of inulin resulted in decreased serum levels of fasting blood glucose (FBG), low-density lipoprotein cholesterol (LDL-C), blood urea nitrogen (BUN), and creatinine (CRE). The administration of inulin not only ameliorated renal injury but also resulted in a reduction in the mRNA expressions of inflammatory factors in the spleen and serum oxidative stress levels, when compared to the DM group. Additionally, inulin treatment in mice with a T2DM model led to a significant increase in the concentrations of three primary short-chain fatty acids (SCFAs) (acetic acid, propionic acid, and butyric acid), while the concentration of advanced glycation end products (AGEs), a prominent inflammatory factor in diabetes, exhibited a significant decrease. The results of untargeted metabolomics indicate that inulin has the potential to alleviate inflammatory response and kidney damage in diabetic mice. This beneficial effect is attributed to its impact on various metabolic pathways, including glycerophospholipid metabolism, taurine and hypotaurine metabolism, arginine biosynthesis, and tryptophan metabolism. Consequently, oral inulin emerges as a promising treatment option for diabetes and kidney injury.
Assuntos
Glicemia, Diabetes Mellitus Experimental, Diabetes Mellitus Tipo 2, Inflamação, Inulina, Rim, Metabolômica, Camundongos Endogâmicos ICR, Estresse Oxidativo, Animais, Inulina/farmacologia, Diabetes Mellitus Tipo 2/complicações, Diabetes Mellitus Tipo 2/sangue, Diabetes Mellitus Tipo 2/tratamento farmacológico, Diabetes Mellitus Tipo 2/metabolismo, Diabetes Mellitus Experimental/sangue, Diabetes Mellitus Experimental/tratamento farmacológico, Diabetes Mellitus Experimental/complicações, Diabetes Mellitus Experimental/metabolismo, Camundongos, Masculino, Glicemia/metabolismo, Glicemia/efeitos dos fármacos, Rim/efeitos dos fármacos, Rim/metabolismo, Rim/patologia, Estresse Oxidativo/efeitos dos fármacos, Nefropatias Diabéticas/tratamento farmacológico, Nefropatias Diabéticas/metabolismo, Nefropatias Diabéticas/sangue, Nefropatias Diabéticas/patologia, Ácidos Graxos Voláteis/metabolismo, Dieta Hiperlipídica, Nitrogênio da Ureia SanguíneaRESUMO
The antibacterial effects of a selection of volatile fatty acids (acetic, propionic, butyric, valeric, and caproic acids) relevant to anaerobic digestion were investigated at 1, 2 and 4 g/L. The antibacterial effects were characterised by the dynamics of Enterococcus faecalis NCTC 00775, Escherichia coli JCM 1649 and Klebsiella pneumoniae A17. Mesophilic anaerobic incubation to determine the minimum bactericidal concentration (MBC) and median lethal concentration of the VFAs was carried out in Luria Bertani broth at 37 °C for 48 h. Samples collected at times 0, 3, 6, 24 and 48 h were used to monitor bacterial kinetics and pH. VFAs at 4 g/L demonstrated the highest bactericidal effect (p < 0.05), while 1 g/L supported bacterial growth. The VFA cocktail was the most effective, while propionic acid was the least effective. Enterococcus faecalis NCTC 00775 was the most resistant strain with the VFAs MBC of 4 g/L, while Klebsiella pneumoniae A17 was the least resistant with the VFAs MBC of 2 g/L. Allowing a 48 h incubation period led to more log decline in the bacterial numbers compared to earlier times. The VFA cocktail, valeric, and caproic acids at 4 g/L achieved elimination of the three bacteria strains, with over 7 log10 decrease within 48 h.
Assuntos
Antibacterianos, Enterococcus faecalis, Ácidos Graxos Voláteis, Klebsiella pneumoniae, Testes de Sensibilidade Microbiana, Ácidos Graxos Voláteis/metabolismo, Ácidos Graxos Voláteis/farmacologia, Antibacterianos/farmacologia, Antibacterianos/química, Enterococcus faecalis/efeitos dos fármacos, Enterococcus faecalis/crescimento & desenvolvimento, Klebsiella pneumoniae/efeitos dos fármacos, Klebsiella pneumoniae/crescimento & desenvolvimento, Anaerobiose, Escherichia coli/efeitos dos fármacos, Escherichia coli/crescimento & desenvolvimento, Propionatos/farmacologia, Concentração de Íons de Hidrogênio, Ácidos Pentanoicos/farmacologiaRESUMO
The gut microbiota and short chain fatty acids (SCFA) have been associated with immune regulation and autoimmune diseases. Autoimmune kidney diseases arise from a loss of tolerance to antigens, often with unclear triggers. In this review, we explore the role of the gut microbiome and how disease, diet, and therapy can alter the gut microbiota consortium. Perturbations in the gut microbiota may systemically induce the translocation of microbiota-derived inflammatory molecules such as liposaccharide (LPS) and other toxins by penetrating the gut epithelial barrier. Once in the blood stream, these pro-inflammatory mediators activate immune cells, which release pro-inflammatory molecules, many of which are antigens in autoimmune diseases. The ratio of gut bacteria Bacteroidetes/Firmicutes is associated with worse outcomes in multiple autoimmune kidney diseases including lupus nephritis, MPO-ANCA vasculitis, and Goodpasture's syndrome. Therapies that enhance SCFA-producing bacteria in the gut have powerful therapeutic potential. Dietary fiber is fermented by gut bacteria which in turn release SCFAs that protect the gut barrier, as well as modulating immune responses towards a tolerogenic anti-inflammatory state. Herein, we describe where the current field of research is and the strategies to harness the gut microbiome as potential therapy.
Assuntos
Doenças Autoimunes, Microbioma Gastrointestinal, Humanos, Microbioma Gastrointestinal/imunologia, Doenças Autoimunes/microbiologia, Doenças Autoimunes/imunologia, Doenças Autoimunes/terapia, Animais, Ácidos Graxos Voláteis/metabolismo, Nefropatias/microbiologia, Nefropatias/imunologia, Nefropatias/terapiaRESUMO
Gestational diabetes mellitus (GDM) is characterized by insulin resistance and low-grade inflammation, and most studies have demonstrated gut dysbiosis in GDM pregnancies. Overall, they were manifested as a reduction in microbiome diversity and richness, depleted short chain fatty acid (SCFA)-producing genera and a dominant of Gram-negative pathogens releasing lipopolysaccharide (LPS). The SCFAs functioned as energy substance or signaling molecules to interact with host locally and beyond the gut. LPS contributed to pathophysiology of diseases through activating Toll-like receptor 4 (TLR4) and involved in inflammatory responses. The gut microbiome dysbiosis was not only closely related with GDM, it was also vital to fetal health through vertical transmission. In this review, we summarized gut microbiota signature in GDM pregnancies of each trimester, and presented a brief introduction of microbiome derived SCFAs. We then discussed mechanisms of microbiome-host interactions in the physiopathology of GDM and associated metabolic disorders. Finally, we compared offspring microbiota composition from GDM with that from normal pregnancies, and described the possible mechanism.
Assuntos
Diabetes Gestacional, Disbiose, Ácidos Graxos Voláteis, Microbioma Gastrointestinal, Diabetes Gestacional/microbiologia, Diabetes Gestacional/metabolismo, Humanos, Gravidez, Feminino, Disbiose/microbiologia, Ácidos Graxos Voláteis/metabolismo, Bactérias/classificação, Bactérias/genética, Bactérias/metabolismo, Bactérias/isolamento & purificação, Interações entre Hospedeiro e Microrganismos, Lipopolissacarídeos/metabolismoRESUMO
HIV infection results in marked alterations in the gut microbiota (GM), such as the loss of microbial diversity and different taxonomic and metabolic profiles. Despite antiretroviral therapy (ART) partially ablating gastrointestinal alterations, the taxonomic profile after successful new ART has shown wide variations. Our objective was to determine the GM composition and functions in people living with HIV (PLWHIV) under ART in comparison to seronegative controls (SC). Fecal samples from 21 subjects (treated with integrase strand-transfer inhibitors, INSTIs) and 18 SC were included. We employed 16S rRNA amplicon sequencing, coupled with PICRUSt2 and fecal short-chain fatty acid (SCFA) quantification by gas chromatography. The INSTI group showed a decreased α-diversity (p < 0.001) compared to the SC group, at the expense of increased amounts of Pseudomonadota (Proteobacteria), Segatella copri, Lactobacillus, and Gram-negative bacteria. Concurrently, we observed an enrichment in Megasphaera and Butyricicoccus, both SCFA-producing bacteria, and significant elevations in fecal butyrate in this group (p < 0.001). Interestingly, gut dysbiosis in PLWHIV was characterized by a proinflammatory environment orchestrated by Pseudomonadota and elevated levels of butyrate associated with bacterial metabolic pathways, as well as the evident presence of butyrogenic bacteria. The role of this unique GM in PLWHIV should be evaluated, as well as the use of butyrate-based supplements and ART regimens that contain succinate, such as tenofovir disoproxil succinate. This mixed profile is described for the first time in PLWHIV from Mexico.
Assuntos
Fezes, Microbioma Gastrointestinal, Infecções por HIV, RNA Ribossômico 16S, Humanos, Infecções por HIV/microbiologia, Infecções por HIV/tratamento farmacológico, México, Feminino, Masculino, Adulto, Pessoa de Meia-Idade, Fezes/microbiologia, RNA Ribossômico 16S/genética, Disbiose/microbiologia, Ácidos Graxos Voláteis/metabolismo, Ácidos Graxos Voláteis/análise, Bactérias/classificação, Bactérias/genética, Bactérias/isolamento & purificação, Butiratos/metabolismoRESUMO
The human gut microbiota, an intricate ecosystem within the gastrointestinal tract, plays a pivotal role in health and disease. Prebiotics, non-digestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of beneficial microorganisms, have emerged as a key modulator of this complex microbial community. This review article explores the evolution of the prebiotic concept, delineates various types of prebiotics, including fructans, galactooligosaccharides, xylooligosaccharides, chitooligosaccharides, lactulose, resistant starch, and polyphenols, and elucidates their impact on the gut microbiota composition. We delve into the mechanisms through which prebiotics exert their effects, particularly focusing on producing short-chain fatty acids and modulating the gut microbiota towards a health-promoting composition. The implications of prebiotics on human health are extensively reviewed, focusing on conditions such as obesity, inflammatory bowel disease, immune function, and mental health. The review further discusses the emerging concept of synbiotics-combinations of prebiotics and probiotics that synergistically enhance gut health-and highlights the market potential of prebiotics in response to a growing demand for functional foods. By consolidating current knowledge and identifying areas for future research, this review aims to enhance understanding of prebiotics' role in health and disease, underscoring their importance in maintaining a healthy gut microbiome and overall well-being.
Assuntos
Microbioma Gastrointestinal, Prebióticos, Humanos, Probióticos/farmacologia, Obesidade/microbiologia, Obesidade/dietoterapia, Obesidade/metabolismo, Ácidos Graxos Voláteis/metabolismo, Animais, Doenças Inflamatórias Intestinais/microbiologia, Doenças Inflamatórias Intestinais/dietoterapiaRESUMO
Ulcerative colitis (UC) is characterized by chronic inflammation and ulceration of the intestinal inner lining, resulting in various symptoms. Sea buckthorn berries contain a bioactive compound known as sea buckthorn polysaccharide (SBP). However, the precise mechanisms underlying the impact of SBP on UC remain unclear. In this study, we investigated the effects of pretreatment with SBP on colitis induced by DSS. Our findings demonstrate that SBP pretreatment effectively reduces inflammation, oxidative stress, and intestinal barrier damage associated with colitis. To further elucidate the role of SBP-modulated gut microbiota in UC, we performed fecal microbiota transplantation (FMT) on DSS-treated mice. The microbiota from SBP-treated mice exhibits notable anti-inflammatory and antioxidant effects, improves colonic barrier integrity, and increases the abundance of beneficial bacteria, as well as enhancing SCFA production. Collectively, these results strongly indicate that SBP-mediated amelioration of colitis is attributed to its impact on the gut microbiota, particularly through the promotion of SCFA-producing bacteria and subsequent elevation of SCFA levels. This study provides compelling evidence supporting the efficacy of pre-emptive SBP supplementation in alleviating colitis symptoms by modulating the gut microbiota, thereby offering novel insights into the potential of SBP as a regulator of the gut microbiota for colitis relief.
Assuntos
Microbioma Gastrointestinal, Hippophae, Polissacarídeos, Animais, Hippophae/química, Polissacarídeos/farmacologia, Microbioma Gastrointestinal/efeitos dos fármacos, Camundongos, Colite/tratamento farmacológico, Colite/induzido quimicamente, Colite/microbiologia, Colite Ulcerativa/microbiologia, Colite Ulcerativa/tratamento farmacológico, Modelos Animais de Doenças, Masculino, Camundongos Endogâmicos C57BL, Estresse Oxidativo/efeitos dos fármacos, Transplante de Microbiota Fecal, Colo/efeitos dos fármacos, Colo/microbiologia, Colo/metabolismo, Sulfato de Dextrana, Anti-Inflamatórios/farmacologia, Antioxidantes/farmacologia, Frutas/química, Ácidos Graxos Voláteis/metabolismoRESUMO
Previous studies have identified a role for the gut microbiome and its metabolic products, short-chain fatty acids (SCFAs), in the maintenance of muscle mass and physical function (i.e., the gut-muscle axis), but interventions aimed at positively impacting the gut-muscle axis during aging are sparse. Gut bacteria ferment soluble fiber into SCFAs, and accordingly, to evaluate the impact of a high-soluble-fiber diet (HSFD) on the gut-muscle axis, we fed a whole-food, 3×-higher-soluble fiber-containing diet (relative to standard chow) to aged (98 weeks) C57BL/6J mice for 10 weeks. The HSFD significantly altered gut bacterial community structure and composition, but plasma SCFAs were not different, and a positive impact on muscle-related measures (when normalized to body weight) was not identified. However, when evaluating sex differences between dietary groups, female (but not male) HSFD-fed mice had significant increases for SCFAs, the quadriceps/body weight (BW) ratio, and treadmill work performance (distance run × BW), which suggests that an HSFD can positively impact the gut-muscle axis. In contrast, consistent effects in both male and female HSFD-fed mice included weight and fat loss, which suggests a positive role for an HSFD on the gut-adipose axis in aged mice.
Assuntos
Envelhecimento, Fibras na Dieta, Ácidos Graxos Voláteis, Microbioma Gastrointestinal, Camundongos Endogâmicos C57BL, Animais, Fibras na Dieta/administração & dosagem, Microbioma Gastrointestinal/fisiologia, Masculino, Feminino, Ácidos Graxos Voláteis/metabolismo, Camundongos, Envelhecimento/fisiologia, Músculo Esquelético/metabolismo, Peso Corporal, DietaRESUMO
BACKGROUND: Cadmium (Cd) is an environmental contaminant that poses risks to human and animal health. Selenium (Se), a beneficial element, alleviates the detrimental consequences of colitis and Cd toxicity. Se is found in food products as both inorganic Se (sodium selenite) and organic Se (typically Se-enriched yeast). Nano-selenium (nano-Se; a novel form of Se produced through the bioreduction of Se species) has recently garnered considerable interest, although its effects against Cd-induced enterotoxicity are poorly understood. The aim of this study was to investigate the impact of nano-selenium on mitigating cadmium toxicity and safeguarding the integrity of the intestinal barrier. METHODS: For a total of two cycles, we subjected 6-week-old C57 mice to chronic colitis by exposing them to Cd and nano-selenium for two weeks, followed by DSS water for one week. RESULTS: The application of nano-selenium mitigated the intensity of colitis and alleviated inflammation in the colon. Nano-selenium enhanced the diversity of the intestinal flora, elevated the concentration of short-chain fatty acids (SCFAs) in feces, and improved the integrity of the intestinal barrier. CONCLUSIONS: In summary, nano-Se may reduce intestinal inflammation by regulating the growth of intestinal microorganisms and protecting the intestinal barrier.
Assuntos
Cádmio, Colite, Microbioma Gastrointestinal, Camundongos Endogâmicos C57BL, Selênio, Animais, Colite/induzido quimicamente, Colite/tratamento farmacológico, Selênio/farmacologia, Microbioma Gastrointestinal/efeitos dos fármacos, Camundongos, Colo/efeitos dos fármacos, Colo/metabolismo, Colo/microbiologia, Masculino, Doença Crônica, Modelos Animais de Doenças, Nanopartículas, Ácidos Graxos Voláteis/metabolismo, Fezes/microbiologia, Sulfato de Dextrana, Mucosa Intestinal/efeitos dos fármacos, Mucosa Intestinal/metabolismo, Mucosa Intestinal/microbiologiaRESUMO
Recent studies have highlighted the lipid-lowering ability of hawthorn ethanol extract (HEE) and the role played by gut flora in the efficacy of HEE. Our study sought to explore the effects of HEE on non-alcoholic fatty liver disease (NAFLD) in normal flora and pseudo germ-free mice. The results showed that HEE effectively diminished hepatic lipid accumulation, ameliorated liver function, reduced inflammatory cytokine levels and blood lipid profiles, and regulated blood glucose levels. HEE facilitated triglyceride breakdown, suppressed fatty acid synthesis, and enhanced intestinal health by modulating the diversity of the gut microbiota and the production of short-chain fatty acids in the gut. In addition, HEE apparently helps to increase the presence of beneficial genera of bacteria, thereby influencing the composition of the gut microbiota, and the absence of gut flora affects the efficacy of HEE. These findings reveal the potential of hawthorn for the prevention and treatment of NAFLD and provide new perspectives on the study of functional plants to improve liver health.
Assuntos
Crataegus, Microbioma Gastrointestinal, Metabolismo dos Lipídeos, Fígado, Hepatopatia Gordurosa não Alcoólica, Extratos Vegetais, Microbioma Gastrointestinal/efeitos dos fármacos, Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico, Hepatopatia Gordurosa não Alcoólica/microbiologia, Extratos Vegetais/farmacologia, Animais, Crataegus/química, Fígado/metabolismo, Fígado/efeitos dos fármacos, Camundongos, Masculino, Metabolismo dos Lipídeos/efeitos dos fármacos, Camundongos Endogâmicos C57BL, Etanol, Modelos Animais de Doenças, Triglicerídeos/sangue, Triglicerídeos/metabolismo, Citocinas/metabolismo, Ácidos Graxos Voláteis/metabolismoRESUMO
Coronary microvascular dysfunction (CMD) is a critical pathogenesis of cardiovascular diseases. Lower endothelial nitric oxide synthase (eNOS) phosphorylation leads to reduced endothelium-derived relaxing factor nitric oxide (NO) generation, causing and accelerating CMD. Endoplasmic reticulum stress (ER stress) has been shown to reduce NO production in umbilical vein endothelial cells. Oxidized low-density lipoprotein (ox-LDL) damages endothelial cell function. However, the relationship between ox-LDL and coronary microcirculation has yet to be assessed. Short-chain fatty acid (SCFA), a fermentation product of the gut microbiome, could improve endothelial-dependent vasodilation in human adipose arterioles, but the effect of SCFA on coronary microcirculation is unclear. In this study, we found ox-LDL stimulated expression of ER chaperone GRP78. Further, we activated downstream PERK/eIF2a, IRE1/JNK, and ATF6 signaling pathways, decreasing eNOS phosphorylation and NO production in human cardiac microvascular endothelial. Furthermore, SCFA-propionate can inhibit ox-LDL-induced eNOS phosphorylation reduction and raise NO production; the mechanism is related to the inhibition of ER stress and downstream signaling pathways PERK/eIF2a, IRE1/JNK, and ATF6. In summary, we demonstrate that ox-LDL induced CMD by activating ER stress, propionate can effectively counteract the adverse effects of ox-LDL and protect coronary microcirculation function via inhibiting ER stress.
Assuntos
Chaperona BiP do Retículo Endoplasmático, Estresse do Retículo Endoplasmático, Lipoproteínas LDL, Óxido Nítrico Sintase Tipo III, Óxido Nítrico, Propionatos, Transdução de Sinais, Humanos, Estresse do Retículo Endoplasmático/efeitos dos fármacos, Lipoproteínas LDL/metabolismo, Óxido Nítrico Sintase Tipo III/metabolismo, Propionatos/farmacologia, Óxido Nítrico/metabolismo, Transdução de Sinais/efeitos dos fármacos, Fosforilação/efeitos dos fármacos, Células Endoteliais/efeitos dos fármacos, Células Endoteliais/metabolismo, Vasos Coronários/efeitos dos fármacos, Vasos Coronários/metabolismo, Ácidos Graxos Voláteis/metabolismo, Ácidos Graxos Voláteis/farmacologia, eIF-2 Quinase/metabolismo, Fator 6 Ativador da Transcrição/metabolismo, Microcirculação/efeitos dos fármacos, Proteínas de Choque Térmico/metabolismoRESUMO
This study aimed to investigate alterations in gut microbiota and metabolites mediated by wheat-resistant starch and its repair of gut barrier dysfunction induced by a high-fat diet (HFD). Structural data revealed that chlorogenic acid (CA)/linoleic acid (LA) functioned through noncovalent interactions to form a more ordered structure and fortify antidigestibility in wheat starch (WS)-CA/LA complexes; the resistant starch (RS) contents of WS-CA, WS-LA, and WS-CA-LA complexes were 23.40 ± 1.56%, 21.25 ± 1.87%, and 35.47 ± 2.16%, respectively. Dietary intervention with WS-CA/LA complexes effectively suppressed detrimental alterations in colon tissue morphology induced by HFD and repaired the gut barrier in ZO-1 and MUC-2 levels. WS-CA/LA complexes could augment gut barrier-promoting microbes including Parabacteroides, Bacteroides, and Muribaculum, accompanied by an increase in short-chain fatty acids (SCFAs) and elevated expression of SCFA receptors. Moreover, WS-CA/LA complexes modulated secondary bile acid metabolism by decreasing taurochenodeoxycholic, cholic, and deoxycholic acids, leading to the activation of bile acid receptors. Collectively, this study offered guiding significance in the manufacture of functional diets for a weak gut barrier.
Assuntos
Ácido Clorogênico, Dieta Hiperlipídica, Microbioma Gastrointestinal, Ácido Linoleico, Camundongos Endogâmicos C57BL, Amido, Triticum, Ácido Clorogênico/metabolismo, Ácido Clorogênico/farmacologia, Ácido Clorogênico/administração & dosagem, Ácido Clorogênico/química, Dieta Hiperlipídica/efeitos adversos, Triticum/química, Triticum/metabolismo, Microbioma Gastrointestinal/efeitos dos fármacos, Animais, Masculino, Camundongos, Amido/metabolismo, Amido/química, Ácido Linoleico/metabolismo, Ácido Linoleico/química, Bactérias/classificação, Bactérias/metabolismo, Bactérias/genética, Bactérias/efeitos dos fármacos, Bactérias/isolamento & purificação, Mucosa Intestinal/metabolismo, Mucosa Intestinal/efeitos dos fármacos, Humanos, Ácidos Graxos Voláteis/metabolismo, Amido Resistente/metabolismoRESUMO
OBJECTIVES: Partially hydrolyzed guar gum (PHGG) is a soluble dietary fiber;in addition to improving bowel movements, it maintains intestinal health by producing short-chain fatty acids. However, majority of clinical studies on PHGG have been concluded within a month and excluded usual drug therapy. Hence, this study aimed to determine the effects of long-term consumption of PHGG, in combination with drug therapy, on gut bacteria ratios, laboratory values for inflammatory response, and fecal characteristics. METHODS AND RESULTS: The study was performed in patients with irritable bowel syndrome (IBS), Crohn's disease (CD), and ulcerative colitis (UC), by the administration of PHGG for six months while they continued their usual treatment. PHGG treatment caused significant changes in patients with IBS, including an increase in the abundance of short-chain fatty acid-producing bacteria, a significant decrease in Bacteroides abundance, and normalization of the Bristol scale of stool. In patients with UC, non-significant normalization of soft stools and decrease in fecal calprotectin were observed. Adverse events were not observed in any of the groups. CONCLUSION: Thus, it would be beneficial to include PHGG in the usual drug therapies of patients with IBS. J. Med. Invest. 71 : 121-128, February, 2024.
Assuntos
Fibras na Dieta, Galactanos, Microbioma Gastrointestinal, Síndrome do Intestino Irritável, Mananas, Gomas Vegetais, Humanos, Microbioma Gastrointestinal/efeitos dos fármacos, Síndrome do Intestino Irritável/tratamento farmacológico, Síndrome do Intestino Irritável/microbiologia, Masculino, Feminino, Fibras na Dieta/administração & dosagem, Adulto, Pessoa de Meia-Idade, Mananas/administração & dosagem, Gomas Vegetais/administração & dosagem, Galactanos/administração & dosagem, Doenças Inflamatórias Intestinais/tratamento farmacológico, Fezes/microbiologia, Fezes/química, Ácidos Graxos Voláteis/análise, Ácidos Graxos Voláteis/metabolismoRESUMO
The evidence on the role of diets in the production of short-chain fatty acids (SCFAs) was limited. The aim of this study was to assess the potential effects of high-fat high-fructose (HFHF), high-fat, and Western diets on the levels of SCFA. A research experiment employing a post-test-only control group design was carried out from January to April 2022. A total of 27 rats were randomly allocated to each study group. SCFA was measured two weeks after diet administration. Analysis of variance (ANOVA) test was used to analyze the differences among groups, and the effect estimate of each group was analyzed using post hoc Tukey. The concentrations of SCFAs post HFHF diets were recorded as follows: acetic acid at 54.60±10.58 mmol/g, propionic acid at 28.03±8.81 mmol/g, and butyric acid at 4.23±1.68 mmol/g. Following the high-fat diet, acetic acid measured 61.85±14.25 mmol/gr, propionic acid measured 25.19±5.55 mmol/gr, and butyric acid measured 6.10±2.93 mmol/gr. After the administration of Western diet, the levels of SCFA were 68.18±25.73, 29.69±12.76, and 7.48±5.51 mmol/g for acetic acid, propionic acid, and butyric acid, respectively. The level of butyric acid was significantly lower in HFHF diet group compared to the normal diet (mean difference (MD) 6.34; 95%CI: 0.61, 12.04; p=0.026). The levels of acetic acid (p=0.419) and propionic acid (p=0.316) were not statistically different among diet types (HFHF, high-fat, and Western diet). In conclusion, HFHF diet is associated with a lower level of butyric acid than the normal diet in a rat model.
Assuntos
Dieta Hiperlipídica, Dieta Ocidental, Modelos Animais de Doenças, Ácidos Graxos Voláteis, Frutose, Hepatopatia Gordurosa não Alcoólica, Animais, Ratos, Dieta Hiperlipídica/efeitos adversos, Ácidos Graxos Voláteis/metabolismo, Hepatopatia Gordurosa não Alcoólica/metabolismo, Hepatopatia Gordurosa não Alcoólica/patologia, Frutose/administração & dosagem, Dieta Ocidental/efeitos adversos, Masculino, Ratos Sprague-Dawley, Ácido AcéticoRESUMO
Dairy buffaloes are typically fed a high-forage, low-quality diet with high fiber. These conditions result in an inherent energy and protein inefficiency. In order to make full and rational use of feed resources and improve the production level and breeding efficiency of dairy buffaloes, the effects of various roughages on nutrient digestibility, ruminal fermentation parameters, and microorganisms in dairy buffaloes were studied in this experiment. Three ternary hybrid buffaloes, with an average body weight of 365 ± 22.1 kg, were selected and fitted with permanent rumen fistulas. They were fed six different diets, each consisting of 1 kg concentrate supplement and one of six types of roughage, including alfalfa hay (A diet), oat hay (O diet), whole corn silage (W diet), king grass (K diet), sugarcane shoot silage (S diet), and rice straw hay (R diet) according to an incomplete Latin square design of 3 × 6, respectively. The pre-feeding period of each period was 12 d. From day 13 to 15 was the official experimental period. During the prefeeding period, free feed intake for each roughage was determined, and during the experiment, the roughage was fed at 90% of the voluntary feed intake. Digestion and metabolism tests were carried out using the total manure collection method to determine the feed intake and fecal output of each buffalo, and to collect feed and fecal samples for chemical analysis. On day 15, rumen fluid samples were collected two hours after morning feeding to determine rumen fermentation parameters and bacterial 16 S rRNA high-throughput sequencing was performed. The results showed that DM and OM digestibility were greatest for the W diet and lowest for the S diet. The rumen pH of the O diet was significantly greater than that of the W diet. The concentration of rumen fluid NH3-N (mg/dL) increased with increased CP content. The concentration of total volatile fatty acids (mmol/L) in the rumen decreased with increased NDF content but increased with increased NFC content. The relative abundances of Bacteroidetes, Firmicutes, and Spirochaetes were 57.03-74.84%, 14.29-21.86%, and 0.44-1.43% in the different quality roughage groups. Bacteroidetes were mainly Prevotellaceae1 and Rikenellaceae RC_gut_group with relative abundances of 30.17-45.75% and 3.23-7.82%. The relative abundance of Patescibacteria and Spirochaetes decreased with increasing roughage quality. These results provide a theoretical and practical basis for evaluating the nutritional value of dairy buffalo feed, utilizing feed resources, matching rations, feeding scientifically, and protecting animal health.
Assuntos
Ração Animal, Bactérias, Búfalos, Fermentação, Rúmen, Animais, Búfalos/microbiologia, Rúmen/microbiologia, Rúmen/metabolismo, Ração Animal/análise, Bactérias/classificação, Bactérias/metabolismo, Bactérias/genética, Bactérias/isolamento & purificação, Fibras na Dieta/metabolismo, Silagem, Nutrientes/metabolismo, Digestão/fisiologia, Dieta/veterinária, RNA Ribossômico 16S/genética, Microbioma Gastrointestinal/fisiologia, Feminino, Ácidos Graxos Voláteis/metabolismo, Ácidos Graxos Voláteis/análiseRESUMO
Rumen cud transfaunation re-establishes rumen micro environment and improves fermentation in recipient animals affected with digestive disorders. Preserving rumen cud or fluid will increase its availability for the treatment of rumen fermentation disorders, without having to maintain donor animals. Rumen fluid collected from healthy goats, fed standard ration having roughage 70% and concentrate 30%, was lyophilized (prefreezing -80 °C, 48 h; lyophilization -45 °C, 32 h) using 5% glycerol as cryoprotectant. The 16 S metagenome analysis of the lyophilized rumen fluid (LRF) revealed an abundance of Prevotella (33.2%). Selenomonas ruminantium (1.87%) and Megasphaera elsdenii (0.23%) were also present. Twenty-four goats having history of high grain feeding and exhibiting clinical symptoms of rumen fermentation disorders were randomly distributed into either one of the two treatment groups viz., T1 = oral administration of LRF 31 g/animal/day and T2 = oral administration of sodium bicarbonate (SB) 15 g/animal/day. Post intervention LRF and SB, improved animal body condition, feed intake, fecal consistency, elevated the ruminal pH at 48 h, reduced propionate and lactate at 48 h, reduced total volatile fatty acids (TVFA) and ammonia nitrogen at 24 h. Significant reduction in serum blood urea nitrogen (BUN) and urea levels were observed even from 24 h post intervention irrespective of the treatments. LRF significantly improved acetate and decreased propionate production compared to SB. LRF at 7.5% (v/v) can thus be used to counteract ruminal fermentation disorders in goats sequel to high grain ration.
Assuntos
Ração Animal, Fermentação, Cabras, Rúmen, Animais, Cabras/fisiologia, Rúmen/microbiologia, Rúmen/metabolismo, Ração Animal/análise, Liofilização, Dieta/veterinária, Grão Comestível/química, Prevotella, Concentração de Íons de Hidrogênio, Ácidos Graxos Voláteis/metabolismo, Ácidos Graxos Voláteis/análise, Acidose/veterinária, Distribuição Aleatória, Megasphaera, Selenomonas, MasculinoRESUMO
This study was conducted to assess the effects of fermented rice bran (FRB) with Ligilactobacillus equi on ruminal fermentation using an in vitro system. Oat hay, corn starch, and wheat bran were used as substrate for control. Ten percent of wheat bran was replaced with rice bran (RB), rice bran fermented with distilled water, and rice bran fermented with L. equi for T1, T2, and T3, respectively. The experimental diets were mixed with buffered rumen fluid from wethers under nitrogen gas and incubated for 24 h at 39°C. The fermentation profile and microbial population were analyzed after the incubations. The results revealed that the RB and FRB (with or without L. equi) significantly reduced the gas, methane (CH4), and CH4 per dry matter digested (p < 0.001). Total short-chain fatty acid was also reduced in T1 and T2 in comparison with the control (p < 0.001). Propionate proportion was increased while butyrate proportion was reduced in response to treatment addition in cultures (p < 0.001). Anaerobic fungi and Fibrobacter succinogenes abundance were decreased in treatments (p < 0.001). Overall, CH4 production in vitro can be reduced by RB and FRB supplementation as a result of the reduction of fiber-degrading microorganisms and a decrease in gas production.
Assuntos
Fibras na Dieta, Ácidos Graxos Voláteis, Fermentação, Metano, Oryza, Rúmen, Animais, Rúmen/microbiologia, Rúmen/metabolismo, Fibras na Dieta/metabolismo, Metano/metabolismo, Ácidos Graxos Voláteis/metabolismo, Técnicas In Vitro, Ração Animal, Fibrobacter/metabolismo, Propionatos/metabolismo, Butiratos/metabolismoRESUMO
BACKGROUND: Gut microbiome metabolites are important modulators of host health and disease. However, the overall metabolic potential of the gut microbiome and interactions with the host organs have been underexplored. RESULTS: Using stable isotope resolved metabolomics (SIRM) in mice orally gavaged with 13C-inulin (a tracer), we first observed dynamic enrichment of 13C-metabolites in cecum contents in the amino acids and short-chain fatty acid metabolism pathways. 13C labeled metabolites were subsequently profiled comparatively in plasma, liver, brain, and skeletal muscle collected at 6, 12, and 24 h after the tracer administration. Organ-specific and time-dependent 13C metabolite enrichments were observed. Carbons from the gut microbiome were preferably incorporated into choline metabolism and the glutamine-glutamate/GABA cycle in the liver and brain, respectively. A sex difference in 13C-lactate enrichment was observed in skeletal muscle, which highlights the sex effect on the interplay between gut microbiome and host organs. Choline was identified as an interorgan metabolite derived from the gut microbiome and fed the lipogenesis of phosphatidylcholine and lysophosphatidylcholine in host organs. In vitro and in silico studies revealed the de novo synthesis of choline in the human gut microbiome via the ethanolamine pathway, and Enterococcus faecalis was identified as a major choline synthesis species. These results revealed a previously underappreciated role for gut microorganisms in choline biosynthesis. CONCLUSIONS: Multicompartmental SIRM analyses provided new insights into the current understanding of dynamic interorgan metabolite transport between the gut microbiome and host at the whole-body level in mice. Moreover, this study singled out microbiota-derived metabolites that are potentially involved in the gut-liver, gut-brain, and gut-skeletal muscle axes. Video Abstract.
Assuntos
Isótopos de Carbono, Microbioma Gastrointestinal, Metabolômica, Músculo Esquelético, Animais, Camundongos, Metabolômica/métodos, Isótopos de Carbono/metabolismo, Masculino, Músculo Esquelético/metabolismo, Feminino, Encéfalo/metabolismo, Fígado/metabolismo, Colina/metabolismo, Camundongos Endogâmicos C57BL, Humanos, Ácidos Graxos Voláteis/metabolismoRESUMO
High nitrate pollution in agriculture and industry poses a challenge to emerging methane oxidation coupled denitrification. In this study, an efficient nitrate removal efficiency of 100 % was achieved at an influent loading rate of 400 mg-N/L·d, accompanied by the production of short chain fatty acids (SCFAs) with a maximum value of 80.9 mg/L. Batch tests confirmed that methane was initially converted to acetate, which then served as a carbon source for denitrification. Microbial community characterization revealed the dominance of heterotrophic denitrifiers, including Simplicispira (22.8 %), Stappia (4.9 %), and the highnitrogen-tolerant heterotrophic denitrifier Diaphorobacter (19.0 %), at the nitrate removal rate of 400 mg-N/L·d. Notably, the low abundance of methanotrophs ranging from 0.24 % to 3.75 % across all operational stages does not fully align with the abundance of pmoA genes, suggesting the presence of other functional microorganisms capable of methane oxidation and SCFAs production. These findings could facilitate highly efficient denitrification driven by methane and contributed to the development of denitrification using methane as an electron donor.
