RESUMEN

Alzheimer's disease (AD) is a degenerative disease that causes a progressive decline in memory and thinking skills. Over the past few years, diverse studies have shown that there is no single cause of AD; instead, it has been reported that factors such as genetics, lifestyle, and environment contribute to the pathogenesis of the disease. In this sense, it has been shown that obesity during middle age is one of the most prominent modifiable risk factors for AD. Of the multiple potential mechanisms linking obesity and AD, the gut microbiota (GM) has gained increasing attention in recent years. However, the underlying mechanisms that connect the GM with the process of neurodegeneration remain unclear. Through this narrative review, we present a comprehensive understanding of how alterations in the GM of people with obesity may result in systemic inflammation and affect pathways related to the pathogenesis of AD. We conclude with an analysis of the relationship between GM and insulin resistance, a risk factor for AD that is highly prevalent in people with obesity. Understanding the crosstalk between obesity, GM, and the pathogenesis of AD will help to design new strategies aimed at preventing neurodegeneration.

Asunto(s)

Enfermedad de Alzheimer , Microbioma Gastrointestinal , Obesidad , Enfermedad de Alzheimer/microbiología , Humanos , Microbioma Gastrointestinal/fisiología , Obesidad/microbiología , Obesidad/complicaciones , Resistencia a la Insulina/fisiología , Animales , Factores de Riesgo , Eje Cerebro-Intestino/fisiología , Inflamación/microbiología

RESUMEN

The gut microbiota is one of the most critical factors in human health. It involves numerous physiological processes impacting host health, mainly via immune system modulation. A balanced microbiome contributes to the gut's barrier function, preventing the invasion of pathogens and maintaining the integrity of the gut lining. Dysbiosis, or an imbalance in the gut microbiome's composition and function, disrupts essential processes and contributes to various diseases. This narrative review summarizes key findings related to the gut microbiota in modern multifactorial inflammatory conditions such as ulcerative colitis or Crohn's disease. It addresses the challenges posed by antibiotic-driven dysbiosis, particularly in the context of C. difficile infections, and the development of novel therapies like fecal microbiota transplantation and biotherapeutic drugs to combat these infections. An emphasis is given to restoration of the healthy gut microbiome through dietary interventions, probiotics, prebiotics, and novel approaches for managing gut-related diseases.

Asunto(s)

Disbiosis , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Obesidad , Probióticos , Humanos , Disbiosis/microbiología , Disbiosis/terapia , Obesidad/microbiología , Probióticos/uso terapéutico , Animales , Inflamación/microbiología , Prebióticos/administración & dosificación

RESUMEN

The consumption of a high-fat high-fructose diet partly resemble the western dietary patterns, which is closely associated with excessive body adiposity and metabolic disorders, such as obesity and type 2 diabetes. Moreover, this unhealthy regime produces unfavourable changes on the faecal microbiota, potentially interfering with microorganisms postbiotic function, such as spermidine, a natural polyamine that has been involved in the control of weight gain. The study aimed to analyse the repercussions of spermidine supplementation on somatic measurements, metabolic markers, and the faecal microbiota profile of rats fed a diet rich in fat and fructose. Indeed, Wistar males with oral administration of spermidine (20 mg/kg/day) for 6 weeks were evaluated for food and energy intake, biochemical markers, and faecal microbiota signatures. The daily use of spermidine decreased weight gain ( P < 0.01), reduced feed efficiency ( P < 0.01), and attenuated visceral fat deposition ( P < 0.01), although no effect on energy intake, hepatic weight, triglyceride and glucose index and atherogenic indexes. Similarly, the consumption of spermidine partially restored the presence of microbial species, notably Akkermansia muciniphila. Elevated concentrations of this species were linked to a decrease in triglycerides ( P = 0.04), indicating that the supplementation of spermidine might contribute to managing energy fuel homeostasis in association with an obesogenic diet.

Asunto(s)

Dieta Alta en Grasa , Heces , Fructosa , Microbioma Gastrointestinal , Ratas Wistar , Espermidina , Animales , Espermidina/farmacología , Masculino , Dieta Alta en Grasa/efectos adversos , Fructosa/efectos adversos , Fructosa/administración & dosificación , Ratas , Microbioma Gastrointestinal/efectos de los fármacos , Heces/microbiología , Obesidad/microbiología , Aumento de Peso/efectos de los fármacos , Suplementos Dietéticos

RESUMEN

Obesity is characterized by specific changes in the composition of the gut microbiota (GM). Exercise can contribute to the modulation of GM. This is the first case study to analyze the composition and metabolism of the GM of an obese runner in a single-stage mountain ultramarathon (MUM) with a mileage of 217 km. Fecal samples were collected 7 days before the race (T0), 15 min after the end of the race (T1), and 7 days after the end of the race (T2). GM composition was analyzed by real-time PCR and shotgun sequencing. We observed a decrease in Bacillota/Bacteroidota ratio and α-diversity after the race. After the 217-km MUM, we observed a decrease in symbiont microorganisms and a notable increase in harmful bacteria. In conclusion, we found that the 217-km MUM may have contributed to the intestinal dysbiosis of the obese runner.

Asunto(s)

Microbioma Gastrointestinal , Obesidad , Humanos , Obesidad/microbiología , Masculino , Carrera de Maratón , Carrera/fisiología , Disbiosis/microbiología , Heces/microbiología , Adulto , Persona de Mediana Edad

RESUMEN

Obesity is a global health concern implicated in numerous chronic degenerative diseases, including type 2 diabetes, dyslipidemia, and neurodegenerative disorders. It is characterized by chronic low-grade inflammation, gut microbiota dysbiosis, insulin resistance, glucose intolerance, and lipid metabolism disturbances. Here, we investigated the therapeutic potential of environmental enrichment (EE) to prevent the progression of gut dysbiosis in mice with high-fat diet (HFD)-induced metabolic syndrome. C57BL/6 male mice with obesity and metabolic syndrome, continuously fed with an HFD, were exposed to EE. We analyzed the gut microbiota of the mice by sequencing the 16s rRNA gene at different intervals, including on day 0 and 12 and 24 weeks after EE exposure. Fasting glucose levels, glucose tolerance, insulin resistance, food intake, weight gain, lipid profile, hepatic steatosis, and inflammatory mediators were evaluated in serum, adipose tissue, and the colon. We demonstrate that EE intervention prevents the progression of HFD-induced dysbiosis, reducing taxa associated with metabolic syndrome (Tepidimicrobium, Acidaminobacteraceae, and Fusibacter) while promoting those linked to healthy physiology (Syntrophococcus sucrumutans, Dehalobacterium, Prevotella, and Butyricimonas). Furthermore, EE enhances intestinal barrier integrity, increases mucin-producing goblet cell population, and upregulates Muc2 expression in the colon. These alterations correlate with reduced systemic lipopolysaccharide levels and attenuated colon inflammation, resulting in normalized glucose metabolism, diminished adipose tissue inflammation, reduced liver steatosis, improved lipid profiles, and a significant reduction in body weight gain despite mice's continued HFD consumption. Our findings highlight EE as a promising anti-inflammatory strategy for managing obesity-related metabolic dysregulation and suggest its potential in developing probiotics targeting EE-modulated microbial taxa.

Asunto(s)

Dieta Alta en Grasa , Disbiosis , Microbioma Gastrointestinal , Ratones Endogámicos C57BL , Obesidad , Animales , Dieta Alta en Grasa/efectos adversos , Disbiosis/microbiología , Ratones , Obesidad/metabolismo , Obesidad/microbiología , Masculino , Glucosa/metabolismo , Ratones Obesos , Resistencia a la Insulina , Síndrome Metabólico/metabolismo , Síndrome Metabólico/etiología , Síndrome Metabólico/microbiología

RESUMEN

Gut fungal imbalances, particularly increased Candida spp., are linked to obesity. This study explored the potential of Lactiplantibacillus plantarum cell-free extracts (postbiotics) to modulate the growth of Candida albicans and Candida kefyr, key members of the gut mycobiota. A minimal synthetic gut model was employed to evaluate the effects of Lactiplantibacillus plantarum postbiotics on fungal growth in mono- and mixed cultures. Microreactors were employed for culturing, fungal growth was quantified using CFU counting, and regression analysis was used to evaluate the effects of postbiotics on fungal growth. Postbiotics at a concentration of 12.5% significantly reduced the growth of both Candida species. At 24 h, both C. albicans and C. kefyr in monocultures exhibited a decrease in growth of 0.11 log CFU/mL. In contrast, mixed cultures showed a more pronounced antifungal effect, with C. albicans and C. kefyr reductions of 0.62 log CFU/mL and 0.64 log CFU/mL, respectively. Regression analysis using the Gompertz model supported the antifungal activity of postbiotics and revealed species-specific differences in growth parameters. These findings suggest that L. plantarum postbiotics have the potential to modulate the gut mycobiota by reducing Candida growth, potentially offering a therapeutic approach for combating fungal overgrowth associated with obesity.

Asunto(s)

Candida , Microbioma Gastrointestinal , Obesidad , Obesidad/microbiología , Candida/efectos de los fármacos , Candida/crecimiento & desarrollo , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Probióticos/farmacología , Candida albicans/efectos de los fármacos , Modelos Biológicos , Antifúngicos/farmacología

RESUMEN

Clostridia are abundant in the human gut and comprise families associated with host health such as Oscillospiraceae, which has been correlated with leanness. However, culturing bacteria within this family is challenging, leading to their detection primarily through 16S rRNA amplicon sequencing, which has a limited ability to unravel diversity at low taxonomic levels, or by shotgun metagenomics, which is hindered by its high costs and complexity. In this cross-sectional study involving 114 Colombian adults, we used an amplicon-based sequencing strategy with alternative markers-gyrase subunit B (gyrB) and DNA K chaperone heat protein 70 (dnaK)-that evolve faster than the 16S rRNA gene. Comparing the diversity and abundance observed with the three markers in our cohort, we found a reduction in the diversity of Clostridia, particularly within Lachnospiraceae and Oscillospiraceae among obese individuals [as measured by the body mass index (BMI)]. Within Lachnospiraceae, the diversity of Ruminococcus_A negatively correlated with BMI. Within Oscillospiraceae, the genera CAG-170 and Vescimonas also exhibited this negative correlation. In addition, the abundance of Vescimonas was negatively correlated with BMI. Leveraging shotgun metagenomic data, we conducted a phylogenetic and genomic characterization of 120 metagenome-assembled genomes from Vescimonas obtained from a larger sample of the same cohort. We identified 17 of the 72 reported species. The functional annotation of these genomes showed the presence of multiple carbohydrate-active enzymes, particularly glycosyl transferases and glycoside hydrolases, suggesting potential beneficial roles in fiber degradation, carbohydrate metabolism, and butyrate production. IMPORTANCE: The gut microbiota is diverse across various taxonomic levels. At the intra-species level, it comprises multiple strains, some of which may be host-specific. However, our understanding of fine-grained diversity has been hindered by the use of the conserved 16S rRNA gene. While shotgun metagenomics offers higher resolution, it remains costly, may fail to identify specific microbes in complex samples, and requires extensive computational resources and expertise. To address this, we employed a simple and cost-effective analysis of alternative genetic markers to explore diversity within Clostridia, a crucial group within the human gut microbiota whose diversity may be underestimated. We found high intra-species diversity for certain groups and associations with obesity. Notably, we identified Vescimonas, an understudied group. Making use of metagenomic data, we inferred functionality, uncovering potential beneficial roles in dietary fiber and carbohydrate degradation, as well as in short-chain fatty acid production.

Asunto(s)

Microbioma Gastrointestinal , Obesidad , Humanos , Microbioma Gastrointestinal/genética , Obesidad/microbiología , Masculino , Adulto , Femenino , Estudios Transversales , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Metagenómica/métodos , Índice de Masa Corporal

RESUMEN

Obesity is advancing at an accelerated pace, and yet its treatment is still an emerging field. Although studies have demonstrated the role of the microbiota in the pathogenesis of obesity, this is the first study to show the effects of intermittent fasting (IF), combined or not with exercise, and high-intensity interval training (HIIT) on the gut microbiota composition in women with obesity. Our hypothesis is that IF combined with HIIT can promote the remodeling of the composition and function of the gut microbiota. Thirty-six women with obesity, aged between 18 and 40 yr, participated in the study. They were randomly divided into three groups: 1) IF associated with HIIT group [IF + exercise group (EX), n = 15]; 2) HIIT group (EX, n = 11); and 3) IF group (IF, n = 10). Interventions took place over 8 wk, and all assessments were performed preintervention and postintervention. The HIIT circuit was performed 3 times/wk, for 25 min/session. The IF protocol was a 5:2 (2 times/wk). Multiplex analysis of inflammatory cytokines, sequencing of the 16S rRNA gene, and gas chromatography to measure fecal concentrations of short-chain fatty acids (SCFAs) were performed. This study was registered on ClinicalTrials.gov (NCT05237154). Exercise increased fecal acetate concentrations (P = 0.04), but no changes were observed in the composition and functional profile of the microbiota. The interventions did not change the composition of the microbiota, but exercise may play a modulatory role in the production of acetate. This investigation provides clinical insights into the use of IF and HIIT for women with obesity.NEW & NOTEWORTHY This is the first investigation about alternate-day fasting combined with HITT on the gut microbiota of obese women. The study contributes to the advancement of human science involving IF and HIIT, popular strategies for managing obesity. Previous evidence has explored IF in modulating the microbiota in animal models or specific populations and clinical conditions. Despite the subtle outcomes, this study has relevance and originality in the field of gut microbiota knowledge.

Asunto(s)

Ayuno , Microbioma Gastrointestinal , Entrenamiento de Intervalos de Alta Intensidad , Obesidad , Humanos , Femenino , Microbioma Gastrointestinal/fisiología , Entrenamiento de Intervalos de Alta Intensidad/métodos , Adulto , Obesidad/microbiología , Obesidad/terapia , Obesidad/metabolismo , Adulto Joven , Adolescente , Ácidos Grasos Volátiles/metabolismo , Heces/microbiología , Ayuno Intermitente

RESUMEN

Obesity, associated with the intake of a high-fat diet (HFD), and anxiety are common among those living in modern urban societies. Recent studies suggest a role of microbiome-gut-brain axis signaling, including a role for brain serotonergic systems in the relationship between HFD and anxiety. Evidence suggests the gut microbiome and the serotonergic brain system together may play an important role in this response. Here we conducted a nine-week HFD protocol in male rats, followed by an analysis of the gut microbiome diversity and community composition, brainstem serotonergic gene expression (tph2, htr1a, and slc6a4), and anxiety-related defensive behavioral responses. We show that HFD intake decreased alpha diversity and altered the community composition of the gut microbiome in association with obesity, increased brainstem tph2, htr1a and slc6a4 mRNA expression, including in the caudal part of the dorsomedial dorsal raphe nucleus (cDRD), a subregion previously associated with stress- and anxiety-related behavioral responses, and, finally, increased anxiety-related defensive behavioral responses. The HFD increased the Firmicutes/Bacteroidetes ratio relative to control diet, as well as higher relative abundances of Blautia, and decreases in Prevotella. We found that tph2, htr1a and slc6a4 mRNA expression were increased in subregions of the dorsal raphe nucleus in the HFD, relative to control diet. Specific bacterial taxa were associated with increased serotonergic gene expression in the cDRD. Thus, we propose that HFD-induced obesity is associated with altered microbiome-gut-serotonergic brain axis signaling, leading to increased anxiety-related defensive behavioral responses in rats.

Asunto(s)

Ansiedad , Eje Cerebro-Intestino , Dieta Alta en Grasa , Microbioma Gastrointestinal , Animales , Masculino , Dieta Alta en Grasa/efectos adversos , Microbioma Gastrointestinal/fisiología , Ansiedad/microbiología , Eje Cerebro-Intestino/fisiología , Ratas , Ratas Sprague-Dawley , Obesidad/microbiología , Obesidad/psicología , Obesidad/metabolismo , Transducción de Señal/fisiología , Conducta Animal/fisiología

RESUMEN

This study aims to investigate the anti-obesity properties of lactic acid bacteria (LAB) isolated from fermented dairy products such as "Airag" and "Khoormog" in Mongolia. These traditional dairy products are widely used in Mongolia and believe in having potential probiotic, anti-diabetes, anti-cancer, and anti-tuberculosis properties and are made from unheated two-humped camel milk and mare milk, respectively. We chose three LAB strains based on their probiotic characteristics, including tolerance of gastric and bile acids. Then we checked the anti-obesity activity of probiotic strains in vivo. An animal model was evaluated in twenty male C57BL/6J mice by inducing obesity with a high-fat diet (HFD), which was divided into five groups: regular diet group (Negative control), HFD group (Positive control), HFD with Lacticaseibacillus paracasei X-1 (X-1), Lacticaseibacillus paracasei X-17 (X-17), and Limosilactobacillus fermentum BM-325 (BM-325). For six weeks, 5 × 109 colony-forming units (CFU) of bacteria were given orally to the LAB-fed groups. Fasting blood glucose (FBG), lipid profiles, organ index, and organ morphology were all measured. The probiotic strains suppressed growth in adipose cell volume, stabilized FBG, reduced liver cell degeneration, and slowed HFD-induced body weight gain. The results suggest that some strains increase general metabolism while lowering body weight.

Asunto(s)

Dieta Alta en Grasa , Ratones Endogámicos C57BL , Obesidad , Probióticos , Animales , Probióticos/administración & dosificación , Dieta Alta en Grasa/efectos adversos , Obesidad/microbiología , Masculino , Ratones , Mongolia , Fármacos Antiobesidad/farmacología , Modelos Animales de Enfermedad , Lactobacillus/aislamiento & purificación , Productos Lácteos Cultivados/microbiología , Camelus

RESUMEN

The Brazilian Cerrado biome is rich in plant biodiversity, with fruits that have unique sensory characteristics and high nutritional quality. Among the various fruits, baru (Dipteryx alata Vog.) has attracted the attention of researchers because of its high lipid, protein, carbohydrate, fiber, and micronutrient (minerals and vitamins) contents. The present study evaluated the effects of regular consumption of baru almonds for over 60 days on the biochemical and anthropometric profiles and fecal microbiota of obese individuals. A pilot study was conducted on 15 individuals with obesity who were instructed to consume a 20-gram portion of baru almonds throughout the day. The body composition was assessed using anthropometric measurements. Blood pressure, glucose levels, lipid profile, serum insulin and iron contents, and fecal microbiota composition were determined at baseline (day 0) and after 60 days. Baru almond consumption contributed to changes in biochemical parameters, improved HDL cholesterol levels, and reduced total and LDL cholesterol levels. Some positive changes in the microbiota composition after consuming baru almonds include a decrease in the Faecalibacterium family and an increase in the Provotella genus. Therefore, ingesting baru almonds can modulate gut microbiota of individuals with obesity.

Asunto(s)

Heces , Microbioma Gastrointestinal , Obesidad , Prunus dulcis , Humanos , Proyectos Piloto , Masculino , Obesidad/microbiología , Femenino , Adulto , Heces/microbiología , Heces/química , Brasil , Persona de Mediana Edad , Glucemia/metabolismo

RESUMEN

Nutraceutical interventions supporting microbiota and eliciting clinical improvements in metabolic diseases have grown significantly. Chronic stress, gut dysbiosis, and metainflammation have emerged as key factors intertwined with sleep disorders, consequently exacerbating the decline in quality of life. This study aimed to assess the effects of two nutraceutical formulations containing prebiotics (fructooligosaccharides (FOS), galactooligosaccharides (GOS), yeast ß-glucans), minerals (Mg, Se, Zn), and the herbal medicine Silybum marianum L. Gaertn., Asteraceae (Milk thistle or Silymarin). These formulations, namely NSupple (without silymarin) and NSupple_Silybum (with silymarin) were tested over 180 days in overweight/obese volunteers from Brazil's southeastern region. We accessed fecal gut microbiota by partial 16S rRNA sequences; cytokines expression by CBA; anthropometrics, quality of life and sleep, as well as metabolic and hormonal parameters, at baseline (T0) and 180 days (T180) post-supplementation. Results demonstrated gut microbiota reshaping at phyla, genera, and species level post-supplementation. The Bacteroidetes phylum, Bacteroides, and Prevotella genera were positively modulated especially in the NSupple_Silybum group. Gut microbiota modulation was associated with improved sleep patterns, quality-of-life perception, cytokines expression, and anthropometric parameters post-supplementation. Our findings suggest that the nutraceutical blends positively enhance cardiometabolic and inflammatory markers. Particularly, NSupple_Silybum modulated microbiota composition, underscoring its potential significance in ameliorating metabolic dysregulation. Clinical trial registry number: NCT04810572. 23/03/2021.

Asunto(s)

Citocinas , Suplementos Dietéticos , Microbioma Gastrointestinal , Calidad de Vida , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Brasil , Femenino , Método Doble Ciego , Adulto , Citocinas/metabolismo , Persona de Mediana Edad , Prebióticos/administración & dosificación , Heces/microbiología , Silimarina/farmacología , Minerales/farmacología , Obesidad/microbiología , Oligosacáridos/farmacología , Oligosacáridos/administración & dosificación

RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a complex disorder whose prevalence is rapidly growing in South America. The disturbances in the microbiota-gut-liver axis impact the liver damaging processes toward fibrosis. Gut microbiota status is shaped by dietary and lifestyle factors, depending on geographic location. We aimed to identify microbial signatures in a group of Chilean MASLD patients. Forty subjects were recruited, including healthy controls (HCs), overweight/obese subjects (Ow/Ob), patients with MASLD without fibrosis (MASLD/F-), and MASLD with fibrosis (MASLD/F+). Both MASLD and fibrosis were detected through elastography and/or biopsy, and fecal microbiota were analyzed through deep sequencing. Despite no differences in α- and ß-diversity among all groups, a higher abundance of Bilophila and a lower presence of Defluviitaleaceae, Lachnospiraceae ND3007, and Coprobacter was found in MASLD/F- and MASLD/F+, compared to HC. Ruminococcaceae UCG-013 and Sellimonas were more abundant in MASLD/F+ than in Ow/Ob; both significantly differed between MASLD/F- and MASLD/F+, compared to HC. Significant positive correlations were observed between liver stiffness and Bifidobacterium, Prevotella, Sarcina, and Acidaminococcus abundance. Our results show that MASLD is associated with changes in bacterial taxa that are known to be involved in bile acid metabolism and SCFA production, with some of them being more specifically linked to fibrosis.

Asunto(s)

Microbioma Gastrointestinal , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Cirrosis Hepática/microbiología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Heces/microbiología , Hígado/metabolismo , Hígado/patología , Hígado Graso/microbiología , Hígado Graso/metabolismo , Hígado Graso/patología , Progresión de la Enfermedad , Obesidad/microbiología , Obesidad/complicaciones , Obesidad/metabolismo , Chile , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/genética , Bacterias/metabolismo , Anciano

RESUMEN

This study examined the interplay between bacterial and fungal communities in the human gut microbiota, impacting on nutritional status and body weight. Cohorts of 10 participants of healthy weight, 10 overweight, and 10 obese individuals, underwent comprehensive analysis, including dietary, anthropometric, and biochemical evaluations. Microbial composition was studied via gene sequencing of 16S and ITS rDNA regions, revealing bacterial (bacteriota) and fungal (mycobiota) profiles. Bacterial diversity exceeded fungal diversity. Statistically significant differences in bacterial communities were found within healthy-weight, overweight, and obese groups. The Bacillota/Bacteroidota ratio (previously known as the Firmicutes/Bacteroidetes ratio) correlated positively with body mass index. The predominant fungal phyla were Ascomycota and Basidiomycota, with the genera Nakaseomyces, Kazachstania, Kluyveromyces, and Hanseniaspora, inversely correlating with weight gain; while Saccharomyces, Debaryomyces, and Pichia correlated positively with body mass index. Overweight and obese individuals who harbored a higher abundance of Akkermansia muciniphila, demonstrated a favorable lipid and glucose profiles in contrast to those with lower abundance. The overweight group had elevated Candida, positively linked to simple carbohydrate consumption. The study underscores the role of microbial taxa in body mass index and metabolic health. An imbalanced gut bacteriota/mycobiota may contribute to obesity/metabolic disorders, highlighting the significance of investigating both communities.

Asunto(s)

Microbioma Gastrointestinal , Micobioma , Saccharomycetales , Humanos , Microbioma Gastrointestinal/genética , Sobrepeso/microbiología , Estado Nutricional , Bacterias/genética , Obesidad/microbiología , Bacteroidetes , Firmicutes

RESUMEN

This systematic review aimed to assess the impact of Bifidobacterium genus probiotics on body weight and body composition parameters in overweight and obese individuals.A systematic search for randomized controlled trials was conducted in MEDLINE, EMBASE, LILACS, and Google Scholar databases until April 17, 2023. The inclusion criteria required the trials to involve Bifidobacterium genus probiotics interventions and the evaluation of obesity-related anthropometric and body composition outcomes in overweight or obese subjects. Studies were excluded when involving obese individuals with genetic syndromes or pregnant women, as well as probiotic mixture interventions. The revised Cochrane risk-of-bias tool for randomized trials was utilized to assess the quality of the included studies. A random-effects meta-analysis was performed using the mean difference between endpoint measurements and change from baseline for body mass index, body weight, body fat mass, body fat percentage, waist circumference, waist-to-hip ratio, and visceral fat area.From 1,527 retrieved reports, 11 studies (911 subjects) were included in this review. Bifidobacterium probiotics administration resulted in significant reductions in body fat mass (MD = -0.64 kg, 95% CI: -1.09, -0.18, p = 0.006), body fat percentage (MD = -0.64%, 95% CI: -1.18, -0.11, p = 0.02), waist circumference (MD = -1.39 cm, 95% CI: -1.99, -0.79, p < 0.00001), and visceral fat area (MD = -4.38 cm2, 95% CI: -7.24, -1.52, p = 0.003). No significant differences were observed for body mass index, body weight, or waist-to-hip ratio.This systematic review suggests that Bifidobacterium genus probiotics may contribute to managing overweight and obesity by reducing body fat mass, body fat percentage, waist circumference, and visceral fat area. Further research is required to understand strain and species interactions, optimal dosages, and effective delivery methods for probiotics in obesity management. This review was pre-registered under the PROSPERO record CRD42022370057.

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Probiotics from the Bifidobacterium genus show promise in reducing body fat mass, body fat percentage, waist circumference, and visceral fat area in overweight and obese adults.Further research is needed to identify the most effective species and strains within the Bifidobacterium genus for achieving these outcomes.There is an urgent need to determine the best probiotic delivery vehicle among enriched foods, capsules, or powders.More randomized controlled trials are necessary to determine optimal probiotic doses and intervention durations.

Asunto(s)

Bifidobacterium , Peso Corporal , Obesidad , Sobrepeso , Probióticos , Adulto , Femenino , Humanos , Masculino , Tejido Adiposo , Composición Corporal/fisiología , Índice de Masa Corporal , Peso Corporal/fisiología , Obesidad/microbiología , Obesidad/terapia , Obesidad/dietoterapia , Sobrepeso/terapia , Sobrepeso/microbiología , Probióticos/uso terapéutico , Probióticos/administración & dosificación , Probióticos/farmacología , Ensayos Clínicos Controlados Aleatorios como Asunto

RESUMEN

Changes in gut microbiota composition and in epigenetic mechanisms have been proposed to play important roles in energy homeostasis, and the onset and development of obesity. However, the crosstalk between epigenetic markers and the gut microbiome in obesity remains unclear. The main objective of this study was to establish a link between the gut microbiota and DNA methylation patterns in subjects with obesity by identifying differentially methylated DNA regions (DMRs) that could be potentially regulated by the gut microbiota. DNA methylation and bacterial DNA sequencing analysis were performed on 342 subjects with a BMI between 18 and 40 kg/m2. DNA methylation analyses identified a total of 2648 DMRs associated with BMI, while ten bacterial genera were associated with BMI. Interestingly, only the abundance of Ruminococcus was associated with one BMI-related DMR, which is located between the MACROD2/SEL1L2 genes. The Ruminococcus abundance negatively correlated with BMI, while the hypermethylated DMR was associated with reduced MACROD2 protein levels in serum. Additionally, the mediation test showed that 19% of the effect of Ruminococcus abundance on BMI is mediated by the methylation of the MACROD2/SEL1L2 DMR. These findings support the hypothesis that a crosstalk between gut microbiota and epigenetic markers may be contributing to obesity development.

Asunto(s)

Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Ruminococcus/genética , Índice de Masa Corporal , Metilación de ADN , Epigénesis Genética , Obesidad/genética , Obesidad/microbiología , ADN , Hidrolasas/genética , Enzimas Reparadoras del ADN/genética

RESUMEN

Obesity often results in severe negative health consequences and represents a growing issue for global health. Reducing food intake is a crucial factor for weight loss. Intermittent fasting is a relatively new intervention that contributes to weight reduction. Considering the intimate relationship between obesity and inflammatory pathologies with gut microbiota alterations, a systematic review of the literature was herein conducted to elucidate the relationship between time-restricted food intake and gut microbiota diversity in humans. Searches are carried out in three databases (PubMed, MedLine/OVID, and Academic Search Complete) between April 2019 and April 2022. Nine studies (all with longitudinal design) were identified as eligible by presenting data about the impact of intermittent fasting schemes on gut microbiota. At the phylum level, Firmicutes and Bacteroidetes increase throughout follow-ups, while 16 bacteria genera change their abundance in response to intermittent fasting. Finally, some genera associated with clinical predictors such as weight change, abdominal circumference, and metabolic variables were reported. Changes induced by fasting schemes positively impact the diversity and abundance of gut microbiota and the biomarkers described here. However, the changes previously reported have been studied in short periods and some return to their basal state after fasting intervention.

Asunto(s)

Bacterias , Microbioma Gastrointestinal , Ayuno Intermitente , Obesidad , Humanos , Animales , Obesidad/microbiología , Obesidad/patología , Obesidad/terapia , Inflamación/microbiología , Bacterias/clasificación , Bacterias/aislamiento & purificación

RESUMEN

Background: Systemic arterial hypertension is linked to a heightened risk of cardiovascular diseases on a global scale. In Mexico, nearly half of adults in vulnerable conditions experience hypertension. Imbalance in the oral and intestinal microbiota composition has been observed in patients with hypertension, documented by a decrease of bacteria producing short-chain fatty acids, which play a critical role in blood pressure regulation. Aim: To examine the cytokines' profile and assess the characteristics of oral and gut microbiota in obesity-related hypertension in Mexican patients. Methods: A cross-sectional, observational, and analytical study was carried out. Twenty-two patients were categorized by their body mass index (BMI) as overweight and obese, and the diagnosis of primary hypertension. DNA from supragingival dental plaque and feces samples was used to carry out 16S rRNA sequencing. Additionally, 13 cytokines were quantified. Results: In the oral microbiota, Kluyvera was found to be significantly enriched in obese compared to overweight patients. Instead, the gut microbiota was dominated by Firmicutes. However, the correlation between certain genera and proinflammatory cytokines was noted. Conclusion: This exploratory study provides insights into the complex relationship between the oral and gut microbiota and their association with systemic inflammation in obesity-related hypertension.

Asunto(s)

Microbioma Gastrointestinal , Hipertensión , Adulto , Humanos , Sobrepeso/complicaciones , Sobrepeso/microbiología , Citocinas , ARN Ribosómico 16S/genética , Estudios Transversales , Obesidad/complicaciones , Obesidad/microbiología , Heces/microbiología , Microbioma Gastrointestinal/fisiología , Hipertensión/complicaciones

RESUMEN

The main objective was to explore the relationship between the microbiota of human milk and adiposity in Mexican mothers during the first lactation stage. METHODS: Seventy lactating women were included. Adiposity by anthropometric measurements and by bioelectric impedance was obtained. The donation of human milk was requested, from which bacterial DNA was extracted and qPCR of the 16S region was performed. The Mann-Whitney U test, Spearman and Pearson correlations, and multiple linear regressions models were also calculated. RESULTS: The median percentage of Bacteroidetes had a direct and significant correlation with normal adiposity, current BMI, waist circumference, and body fat percentage. The correlation with current BMI became significantly inverse in women with BMI ≥ 25. In women with normal BMI, the percentage of Actinobacteria showed a direct and significant correlation with current BMI, waist circumference, and percentage of body fat. Multiple linear regressions showed that pre-pregnancy BMI was the variable with the highest predictive value with the Bacteroidetes phyla in normal BMI and in BMI ≥ 25. CONCLUSIONS: the adiposity of the woman before pregnancy and during lactation would have an important effect on the abundance of Bacteroidetes and Actinobacteria in human milk.

Asunto(s)

Actinobacteria , Obesidad Materna , Adiposidad , Bacterias , Bacteroidetes , Índice de Masa Corporal , Femenino , Firmicutes , Humanos , Lactancia , Leche Humana , Obesidad/microbiología , Embarazo

RESUMEN

Akkermansia muciniphila is a Gram-negative anaerobic mucus-layer-degrading bacterium that colonizes the intestinal mucosa of humans and rodents. Metagenomic data have shown an inverse correlation between the abundance of A. muciniphila and diseases such as inflammatory bowel disease (IBD), obesity, and diabetes. Thus, in recent decades, the potential of this bacterium as an immunomodulatory probiotic for autoimmune and chronic inflammatory diseases has been explored in experimental models. Corroborating these human correlation data, it has been reported that A. muciniphila slows down the development and progression of diabetes, obesity, and IBD in mice. Consequently, clinical studies with obese and diabetic patients are being performed, and the preliminary results are very promising. Therefore, this mini review highlights the main findings regarding the beneficial roles of A. muciniphila and its action mechanisms in autoimmune and chronic inflammatory diseases.

Asunto(s)

Akkermansia , Diabetes Mellitus , Enfermedades Inflamatorias del Intestino , Obesidad , Animales , Enfermedad Crónica , Diabetes Mellitus/microbiología , Microbioma Gastrointestinal , Humanos , Sistema Inmunológico , Enfermedades Inflamatorias del Intestino/microbiología , Ratones , Obesidad/microbiología