Microbial dysbiosis-induced obesity: role of gut microbiota in homoeostasis of energy metabolism

Effect of Lacticaseibacillus paracasei K56 with galactooligosaccharide synbiotics on obese individuals: an in vitro fermentation model

BACKGROUND

The use of synbiotics is emerging as a promising intervention strategy for regulating the gut microbiota and for preventing or reducing obesity, in comparison with the use of probiotics or prebiotics alone. A previous in vivo study revealed that Lacticaseibacillus paracasei K56 (L. paracasei K56) could alleviate obesity induced in high-fat-diet mice; however, the effect of the synbiotic combination of L. paracasei K56 and prebiotics in obese individuals has not been explored fully.

RESULTS

The effect of prebiotics on the proliferation of L. paracasei K56 was determined by spectrophotometry. The results showed that polydextrose (PG), xylooligosaccharide (XOS), and galactooligosaccharide (GOS) had a greater potential to be used as substrates for L. paracasei K56 than three other prebiotics (melitose, stachyose, and mannan-oligosaccharide). An in vitro fermentation model based on the feces of ten obese female volunteers was then established. The results revealed that K56_GOS showed a significant increase in GOS degradation rate and short-chain fatty acid (SCFA) content, and a decrease in gas levels, compared with PG, XOS, GOS, K56_PG, and K56_XOS. Changes in these microbial biomarkers, including a significant increase in Bacteroidota, Bifidobacterium, Lactobacillus, Faecalibacterium, and Blautia and a decrease in the Firmicutes/Bacteroidota ratio and Escherichia-Shigella in the K56_GOS group, were associated with increased SCFA content and decreased gas levels.

CONCLUSION

This study demonstrates the effect of the synbiotic combination of L. paracasei K56 and GOS on obese individuals and indicates its potential therapeutic role in obesity treatment. © 2024 Society of Chemical Industry.

Aflatoxin B1-induced liver pyroptosis is mediated by disturbing the gut microbial metabolites: The roles of pipecolic acid and norepinephrine

The disturbed gut microbiota is a key factor in activating the aflatoxin B1 (AFB1)-induced liver pyroptosis by promoting inflammatory hepatic injury; however, the pathogen associated molecular pattern (PAMP) from disturbed gut microbiota and its mechanism in activating liver pyroptosis remain undefined. By transplanting AFB1-originated fecal microbiota and sterile fecal microbial metabolites filtrate, we determined the association of PAMP in AFB1-induced liver pyroptosis. Notably, AFB1-originated sterile fecal microbial metabolites filtrate were more active in triggering liver pyroptosis in mice, as compared to parental fecal microbiota. This result supported a critical role of the metabolic homeostasis of gut microbiota in AFB1-induced liver pyroptosis, rather than an injurious response to direct exposure of AFB1 in liver. Among the gut-microbial metabolites, pipecolic acid and norepinephrine were proposed to bind TLR4 and NLRP3, the upstream proteins of pyroptosis signaling pathway. Besides, the activations of TLR4 and NLRP3 were linearly correlated with the concentrations of pipecolic acid and norepinephrine in the serum of mice. In silenced expression of TLR4 and NLRP3 in HepG2 cells, pipecolic acid or norepinephrine did not able to activate hepatocyte pyroptosis. These results demonstrated the necessity of gut microbial metabolism in sustaining liver homeostasis, as well as the potential to provide new insights into targeted intervention for AFB1 hepatotoxicity.

Lipid metabolism regulation by dietary polysaccharides with different structural properties

Lipid metabolism plays an important role in energy homeostasis maintenance in response to stress. Nowadays, hyperlipidemia-related chronic diseases such as obesity, diabetes, atherosclerosis, and fatty liver pose significant health challenges. Dietary polysaccharides (DPs) have gained attention for their effective lipid-lowering properties. This review examines the multifaceted mechanisms that DPs employ to lower lipid levels in subjects with hyperlipidemia. DPs could directly inhibit lipid intake and absorption, promote lipid excretion, and regulate key enzymes involved in lipid metabolism pathways, including triglyceride and cholesterol anabolism and catabolism, fatty acid oxidation, and bile acid synthesis. Additionally, DPs indirectly improve lipid homeostasis by modulating gut microbiota composition and alleviating oxidative stress. Moreover, the lipid-lowering mechanisms of particular structural DPs (including β-glucan, pectin, glucomannan, inulin, arabinoxylan, and fucoidan) are summarized. The relationship between the structure and lipid-lowering activity of DPs is also discussed based on current researches. Finally, potential breakthroughs and future directions in the development of DPs in lipid-lowering activity are discussed. The paper could provide a reference for further exploring the mechanism of DPs for lipid regulations and utilizing DPs as lipid-lowering dietary ingredients.

Hyperbaric oxygen therapy ameliorates intestinal and systematic inflammation by modulating dysbiosis of the gut microbiota in Crohn's disease

BACKGROUND

Dysbiosis of the gut microbiota is pivotal in Crohn's disease (CD) and modulated by host physiological conditions. Hyperbaric oxygen therapy (HBOT) is a promising treatment for CD that can regulate gut microbiota. The relationship between HBOT and the gut microbiota in CD remains unknown.

METHODS

CD patients were divided into an HBOT group (n = 10) and a control group (n = 10) in this open-label prospective interventional study. The fecal samples before and after HBOT were used for 16 S rRNA gene sequencing and fecal microbiota transplantation (FMT). A colitis mouse model was constructed using dextran sulfate sodium, and intestinal and systematic inflammation was evaluated. The safety and long-term effect of HBOT were observed.

RESULTS

HBOT significantly reduced the level of C-reactive protein (CRP) (80.79 ± 42.05 mg/L vs. 33.32 ± 18.31 mg/L, P = 0.004) and the Crohn's Disease Activity Index (CDAI) (274.87 ± 65.54 vs. 221.54 ± 41.89, P = 0.044). HBOT elevated the declined microbial diversity and ameliorated the altered composition of gut microbiota in patients with CD. The relative abundance of Escherichia decreased, and that of Bifidobacterium and Clostridium XIVa increased after HBOT. Mice receiving FMT from donors after HBOT had significantly less intestinal inflammation and serum CRP than the group before HBOT. HBOT was safe and well-tolerated by patients with CD. Combined with ustekinumab, more patients treated with HBOT achieved clinical response (30%vs.70%, P = 0.089) and remission (20%vs.50%, P = 0.160) at week 4.

CONCLUSIONS

HBOT modulates the dysbiosis of gut microbiota in CD and ameliorates intestinal and systematic inflammation. HBOT is a safe option for CD and exhibits a promising auxiliary effect to ustekinumab.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2200061193. Registered 15 June 2022, https://www.chictr.org.cn/showproj.html?proj=171605 .

Relationship between Rumen Microbial Differences and Phenotype Traits among Hu Sheep and Crossbred Offspring Sheep

This experiment was conducted to investigate the effect of three-way hybrid sheep and Hu sheep on serum indicators, rumen fermentation, rumen enzyme activity, and microorganisms in sheep. Healthy and similar birth weights from three groups (Hu, n = 11; Charolais × Australian White × Hu, CAH, n = 11; Charolais × Dorper × Hu, CDH, n = 11) were selected to be fed by the ewes until 45 days of age. Subsequently, they were weaned intensively and underwent short-term fattening for 3 months along with selected male lambs fed intensively. During this period, they were fed and watered ad libitum. Blood and rumen fluid were collected and analyzed for serum indicators and rumen fluid microorganisms, enzyme activity, and VFA, respectively, at the end of the fattening period. Compared with Hu lamb, the offspring of the three-way hybrid lamb showed significant improvements in body weight, serum lactate dehydrogenase, and creatinine content. However, there was no significant effect on serum immunity and antioxidant indices. In addition, the rumen fluid volatile fatty acid (VFA) molar concentration and microcrystalline cellulose and lipase content were significantly lower in the three-way hybrid lamb compared to Hu lamb, but β-glucosidase, amylase, pepsin, and VFA molar ratio were not significantly affected. Subsequently, 16S rRNA sequencing diversity analysis revealed that three-way hybrid lamb significantly increased rumen microbial ACE and Chao1 indices compared to Hu lamb. Meanwhile, the abundance of Verrucomicrobiota and Synergistota significantly increased at the phylum level. Correlation analysis showed that Prevotella had the highest proportion, while Rikenellaceae_RC9_gut_group correlated most closely with others genus. The microbial communities isovaleric acid molar concentration and proportion were strongly correlated. In addition, there were significant differences in correlations between microbial communities and isobutyric acid, butyric acid and valeric acid content, and their molar proportion, but they were not significantly correlated with digestive enzymes. From the functional enrichment analysis, it was found that hybrid progeny were mainly enriched in the pyruvate metabolism, microbial metabolism in diverse environments, carbon metabolism, and quorum sensing pathways. In contrast, the Hu sheep were primarily enriched in the cysteine and methionine, amino sugar and nucleotide sugar, and biosynthesis of secondary metabolite pathways. These results suggest that hybridization can play a role in regulating organismal metabolism and improve animal production performance by influencing the structure and characteristics of microbial communities.

Metformin use associated with lower rate of hospitalization for influenza in individuals with diabetes

AIM

To investigate if patients with diabetes taking metformin have better outcomes versus those not taking metformin following an emergency room visit for influenza.

METHODS

Using electronic medical records, we performed a retrospective chart review of all adult patients with a diagnosis of diabetes seen in any Duke University Medical Center-affiliated emergency department for influenza over a 6-year period. We documented patient characteristics and comorbidities, and compared outcomes for patients taking metformin versus patients not taking metformin using both univariable and multivariable analyses. Our primary outcome was hospital admission rate. Secondary outcomes were in-hospital length of stay and in-hospital death.

RESULTS

Our cohort included 1023 adult patients with diabetes, of whom 59.9% were female. The mean age was 62.9 years, 58.4% were African American, 36.1% were White, and 81.9% were obese or overweight. Of these patients, 347 (34%) were taking metformin. Patients with diabetes taking metformin were less likely to be hospitalized following an emergency department visit for influenza than patients with diabetes not taking metformin (56.8% vs. 70.1%; p < 0.001). Of those patients admitted, there was no statistically significant difference in length of stay or death.

CONCLUSIONS

In patients with diabetes, metformin use is associated with lower rate of hospitalization following an emergency department visit for influenza.

Role of gut microbiota in doxorubicin-induced cardiotoxicity: from pathogenesis to related interventions

Doxorubicin (DOX) is a broad-spectrum and highly efficient anticancer agent, but its clinical implication is limited by lethal cardiotoxicity. Growing evidences have shown that alterations in intestinal microbial composition and function, namely dysbiosis, are closely linked to the progression of DOX-induced cardiotoxicity (DIC) through regulating the gut-microbiota-heart (GMH) axis. The role of gut microbiota and its metabolites in DIC, however, is largely unelucidated. Our review will focus on the potential mechanism between gut microbiota dysbiosis and DIC, so as to provide novel insights into the pathophysiology of DIC. Furthermore, we summarize the underlying interventions of microbial-targeted therapeutics in DIC, encompassing dietary interventions, fecal microbiota transplantation (FMT), probiotics, antibiotics, and natural phytochemicals. Given the emergence of microbial investigation in DIC, finally we aim to point out a novel direction for future research and clinical intervention of DIC, which may be helpful for the DIC patients.

Anti-steatotic effects of PPAR-alpha and gamma involve gut-liver axis modulation in high-fat diet-fed mice

AIM

To evaluate the effects of PPARα and PPARγ activation (alone or in combination) on the gut-liver axis, emphasizing the integrity of the intestinal barrier and hepatic steatosis in mice fed a high saturated fat diet.

METHODS

Male C57BL/6J were fed a control diet (C) or a high-fat diet (HF) for ten weeks. Then, a four-week treatment started: HF-α (WY14643), HF-γ (low-dose pioglitazone), and HF-αγ (combination).

RESULTS

The HF caused overweight, insulin resistance, impaired gut-liver axis, and marked hepatic steatosis. Treatments reduced body mass, improved glucose homeostasis, and restored the gut microbiota diversity and intestinal barrier gene expression. Treatments also lowered the plasma lipopolysaccharide concentrations and favored beta-oxidation genes, reducing macrophage infiltration and steatosis in the liver.

CONCLUSION

Treatment with PPAR agonists modulated the gut microbiota and rescued the integrity of the intestinal barrier, alleviating hepatic steatosis. These results show that these agonists can contribute to metabolic-associated fatty liver disease treatment.

The link between obesity and the gut microbiota and immune system in early-life

In early-life, the gut microbiota is highly modifiable, being modulated by external factors such as maternal microbiota, mode of delivery, and feeding strategies. The composition of the child's gut microbiota will deeply impact the development and maturation of its immune system, with consequences for future health. As one of the main sources of microorganisms to the child, the mother represents a crucial factor in the establishment of early-life microbiota, impacting the infant's wellbeing. Recent studies have proposed that dysbiotic maternal gut microbiota could be transmitted to the offspring, influencing the development of its immunity, and leading to the development of diseases such as obesity. This paper aims to review recent findings in gut microbiota and immune system interaction in early-life, highlighting the benefits of a balanced gut microbiota in the regulation of the immune system.

Structural characterization and immunomodulatory activity of a polysaccharide from Dioscotea opposita

The purified polysaccharides fraction, DOP-2, was prepared from Dioscorea opposita Thunb (D. opposita). This study combined in vitro and in vivo experiments to comprehensively investigate the index changes in RAW264.7 cells and immunocompromised mice under DOP-2 intervention, aiming to elucidate the potential mechanisms of immunomodulatory effects of DOP-2. DOP-2 (10 ∼ 500 μg/mL) significantly elevated the levels of NO, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) factors secreted by RAW264.7 cells, and restored the body weight of immunosuppressed mice and improve the degree of injury to the immune organ index, resulting in significant immunomodulatory effects. Notably, DOP-2 promoted the production of short-chain fatty acids (SCFAs) in immunosuppressed mice and modulated the composition of their gut microflora. These findings highlight the potential benefits of DOP-2 therapy in improving immune function and gut health, and will provide a theoretical basis for the application of D. opposita polysaccharides as an immunomodulatory adjuvant.

Loss of Paneth cells dysregulates gut ILC subsets and enhances weight gain response to high fat diet in a mouse model

Obesity has been associated with dysbiosis, but innate mechanisms linking intestinal epithelial cell subsets and obesity remain poorly understood. Using mice lacking Paneth cells (Sox9 ΔIEC mice), small intestinal epithelial cells specialized in the production of antimicrobial products and cytokines, we show that dysbiosis alone does not induce obesity or metabolic disorders. Loss of Paneth cells reduced ILC3 and increased ILC2 numbers in the intestinal lamina propria. High-fat diet (HFD) induced higher weight gain and more severe metabolic disorders in Sox9 ΔIEC mice. Further, HFD enhances the number of ILC1 in the intestinal lamina propria of Sox9 ΔIEC mice and increases intestinal permeability and the accumulation of immune cells (inflammatory macrophages and T cells, and B cells) in abdominal fat tissues of obese Sox9 ΔIEC . Transplantation of fecal materials from Sox9 ΔIEC mice in germ-free mice before HFD further confirmed the regulatory role of Paneth cells for gut ILC subsets and the development of obesity.

The potential of short-chain fatty acid epigenetic regulation in chronic low-grade inflammation and obesity

Obesity and chronic low-grade inflammation, often occurring together, significantly contribute to severe metabolic and inflammatory conditions like type 2 diabetes (T2D), cardiovascular disease (CVD), and cancer. A key player is elevated levels of gut dysbiosis-associated lipopolysaccharide (LPS), which disrupts metabolic and immune signaling leading to metabolic endotoxemia, while short-chain fatty acids (SCFAs) beneficially regulate these processes during homeostasis. SCFAs not only safeguard the gut barrier but also exert metabolic and immunomodulatory effects via G protein-coupled receptor binding and epigenetic regulation. SCFAs are emerging as potential agents to counteract dysbiosis-induced epigenetic changes, specifically targeting metabolic and inflammatory genes through DNA methylation, histone acetylation, microRNAs (miRNAs), and long non-coding RNAs (lncRNAs). To assess whether SCFAs can effectively interrupt the detrimental cascade of obesity and inflammation, this review aims to provide a comprehensive overview of the current evidence for their clinical application. The review emphasizes factors influencing SCFA production, the intricate connections between metabolism, the immune system, and the gut microbiome, and the epigenetic mechanisms regulated by SCFAs that impact metabolism and the immune system.

Resistant Starch from Purple Sweet Potatoes Alleviates Dextran Sulfate Sodium-Induced Colitis through Modulating the Homeostasis of the Gut Microbiota

Ulcerative colitis (UC) is a complicated inflammatory disease with a continually growing incidence. In this study, resistant starch was obtained from purple sweet potato (PSPRS) by the enzymatic isolation method. Then, the structural properties of PSPRS and its protective function in dextran sulfate sodium (DSS)-induced colitis were investigated. The structural characterization results revealed that the crystallinity of PSPRS changed from CA-type to A-type, and the lamellar structure was totally destroyed during enzymatic hydrolysis. Compared to DSS-induced colitis mice, PSPRS administration significantly improved the pathological phenotype and colon inflammation in a dose-dependent manner. ELISA results indicated that DSS-induced colitis mice administered with PSPRS showed higher IL-10 and IgA levels but lower TNF-α, IL-1β, and IL-6 levels. Meanwhile, high doses (300 mg/kg) of PSPRS significantly increased the production of acetate, propionate, and butyrate. 16S rDNA high-throughput sequencing results showed that the ratio of Firmicutes to Bacteroidetes and the potential probiotic bacteria levels were notably increased in the PSPRS treatment group, such as Lactobacillus, Alloprevotella, Lachnospiraceae_NK4A136_group, and Bifidobacterium. Simultaneously, harmful bacteria like Bacteroides, Staphylococcus, and Akkermansia were significantly inhibited by the administration of a high dose of PSPRS (p < 0.05). Therefore, PSPRS has the potential to be a functional food for promoting intestinal health and alleviating UC.

Gut Microbiota: Potential Therapeutic Target for Sickle Cell Disease Pain and Complications

Aim

Sickle cell disease has witnessed a 41.4% surge from 2000 to 2021, significantly affecting morbidity and mortality rates, particularly in children from regions with elevated under-5 mortality rates. Gut microbiota dysbiosis is increasingly recognised in SCD, exacerbating complications, particularly chronic pain, marked by significant alterations of proinflammatory bacteria abundance. This review explores the therapeutic potential of Akkermansia muciniphila and Roseburia spp. in alleviating SCD-related complications, emphasising their roles in maintaining gut barrier integrity, reducing inflammation, and modulating immune responses.

Method

A literature search up to November 2023 using PubMed, MEDLINE, and Google Scholar databases explored SCD pathophysiology, gut microbiota composition, Akkermansia muciniphila and Roseburia spp. abundance, pain and gut dysbiosis in SCD, and butyrate therapy.

Result

A. muciniphila and Roseburia spp. supplementation shows promise in alleviating chronic pain by addressing gut dysbiosis, offering new avenues for sustainable SCD management. This approach holds the potential for reducing reliance on reactive treatments and improving overall quality of life. This research underscores the pivotal role of the gut microbiome in SCD, advocating for personalised treatment approaches.

Conclusion

Further exploration and clinical trials are needed to harness the full potential of these gut bacteria for individuals affected by this challenging condition.

The hidden threat: Environmental toxins and their effects on gut microbiota

The human gut microbiota (GM), which consists of a complex and diverse ecosystem of bacteria, plays a vital role in overall wellness. However, the delicate balance of this intricate system is being compromised by the widespread presence of environmental toxins. The intricate connection between contaminants in the environment and human well-being has garnered significant attention in recent times. Although many environmental pollutants and their toxicity have been identified and studied in laboratory settings and animal models, there is insufficient data concerning their relevance to human physiology. Consequently, research on the toxicity of environmental toxins in GM has gained prominence in recent years. Various factors, such as air pollution, chemicals, heavy metals, and pesticides, have a detrimental impact on the composition and functioning of the GM. This comprehensive review aims to comprehend the toxic effects of numerous environmental pollutants, including antibiotics, endocrine-disrupting chemicals, heavy metals, and pesticides, on GM by examining recent research findings. The current analysis concludes that different types of environmental toxins can lead to GM dysbiosis and have various potential adverse effects on the well-being of animals. We investigate the alterations to the GM composition induced by contaminants and their impact on overall well-being, providing a fresh perspective on research related to pollutant exposure.

Raspberry polysaccharides attenuate hepatic inflammation and oxidative stress in diet-induced obese mice by enhancing butyrate-mediated intestinal barrier function

Obesity and associated liver diseases are becoming global public health challenges. Raspberry (Rubus chingii Hu.), as a medicine food homology plant, possesses a series of health-promoting properties, but its protective effect on obesity-related liver injury and the potential mechanisms remain obscure. Herein high-fat diet (HFD)-fed mice were orally treated with raspberry polysaccharides (RCP) for 14 weeks. Treatment with RCP alleviated obesity and associated symptoms including hyperglycemia, hyperlipemia, endotoxemia, as well as hepatic inflammation and oxidant stress in HFD-induced obese mice. RCP restructured the gut microbiota and host metabolism especially by increasing the levels of Dubosiella and its metabolite butyrate. Besides, exogenous butyrate supplementation protected against intestinal barrier disruption, and thereby reduced inflow of lipopolysaccharide and mitigated inflammation and oxidative injury in the liver of obese mice. Therefore, we suggest that RCP can be utilized as a novel prebiotics to improve obesity-induced hepatic oxidative injury by enhancing butyrate-mediated intestinal barrier function.

NURECON: A Novel Online System for Determining Nutrition Requirements Based on Microbial Composition

Dietary habits have been proven to have an impact on the microbial composition and health of the human gut. Over the past decade, researchers have discovered that gut microbiota can use nutrients to produce metabolites that have major implications for human physiology. However, there is no comprehensive system that specifically focuses on identifying nutrient deficiencies based on gut microbiota, making it difficult to interpret and compare gut microbiome data in the literature. This study proposes an analytical platform, NURECON, that can predict nutrient deficiency information in individuals by comparing their metagenomic information to a reference baseline. NURECON integrates a next-generation bacterial 16S rRNA analytical pipeline (QIIME2), metabolic pathway prediction tools (PICRUSt2 and KEGG), and a food compound database (FooDB) to enable the identification of missing nutrients and provide personalized dietary suggestions. Metagenomic information from total number of 287 healthy subjects was used to establish baseline microbial composition and metabolic profiles. The uploaded data is analyzed and compared to the baseline for nutrient deficiency assessment. Visualization results include gut microbial composition, related enzymes, pathways, and nutrient abundance. NURECON is a user-friendly online platform that provides nutritional advice to support dietitians' research or menu design.

Inulin-type fructans with different degrees of polymerization improve insulin resistance, metabolic parameters, and hormonal status in overweight and obese women with polycystic ovary syndrome: A randomized double-blind, placebo-controlled clinical trial

Polycystic ovary syndrome (PCOS) is associated with reproductive disorders and adverse cardiometabolic risk factors that can negatively impact the general health of women. Inulin-type fructans (ITFs) are proposed to beneficially affect risk factors associated with metabolic disorders. Whether ITFs can help with the management of PCOS by modifying insulin resistance (IR) and androgen levels has not yet been explored. The aim of this study was to investigate the effects of ITFs with different degrees of polymerization on insulin resistance, blood lipids, anthropometric measures, and hormonal status in overweight and obese women with PCOS. In a randomized double-blind placebo-controlled trial, seventy-five women with PCOS aged 18-40 years old were randomly assigned to receive 10 g/day of high-performance inulin (HPI) or oligofructose-enriched inulin (OEI) or maltodextrin for 12 weeks. Biochemical and clinical outcomes were measured at baseline and after the intervention. Participants in the HPI and OEI groups experienced improvements in waist circumference, total testosterone, free androgen index, sex hormone-binding globulin, and triglycerides compared to the placebo group. Also, the number of women with irregular menses or oligomenorrhoea decreased significantly in both ITF groups. Participants in the HPI group reported lower body mass, fasting insulin, and HOMA-IR, as well as a higher quantitative insulin sensitivity check index. ITF supplementation, especially with long-chain ITFs, when given for 12 weeks may improve metabolic outcomes, androgen status and clinical manifestations in women with PCOS.

Exploring the Dynamic Relationship between the Gut Microbiome and Body Composition across the Human Lifespan: A Systematic Review

This systematic review aimed to identify different gut microbiome profiles across the human lifespan and to correlate such profiles with the body composition. PubMed, Scopus, and Cochrane were searched from inception to March 2022. Sixty studies were included in this systematic review. Overall, the gut microbiome composition in overweight participants exhibited decreased α-diversity, decreased levels of the phylum Bacteroidetes and its taxa, and increased levels of the phylum Firmicutes, its taxa, and the Firmicutes/Bacteroidetes ratio, in comparison to normal-weight participants. Other body composition parameters showed similar correlations. Fat mass and waist circumference were found to correlate positively with the Firmicutes taxa and negatively with the Bacteroidetes taxa. In contrast, lean body mass and muscle mass demonstrated a positive correlation with the Bacteroidetes taxa. Notably, these correlations were more pronounced in athletes than in obese and normal-weight individuals. The composition of the gut microbiome is evidently different in overweight individuals or athletes of all age groups, with the former tending towards decreased Bacteroidetes taxa and increased Firmicutes taxa, while a reversed relationship is observed concerning athletes. Further studies are needed to explore the dynamic relationship between energy intake, body composition, and the gut microbiome across the human lifespan.

Clinically Effective Molecules of Natural Origin for Obesity Prevention or Treatment

The prevalence and incidence of obesity and the comorbidities linked to it are increasing worldwide. Current therapies for obesity and associated pathologies have proven to cause a broad number of adverse effects, and often, they are overpriced or not affordable for all patients. Among the alternatives currently available, natural bioactive compounds stand out. These are frequently contained in pharmaceutical presentations, nutraceutical products, supplements, or functional foods. The clinical evidence for these molecules is increasingly solid, among which epigallocatechin-3-gallate, ellagic acid, resveratrol, berberine, anthocyanins, probiotics, carotenoids, curcumin, silymarin, hydroxy citric acid, and α-lipoic acid stand out. The molecular mechanisms and signaling pathways of these molecules have been shown to interact with the endocrine, nervous, and gastroenteric systems. They can regulate the expression of multiple genes and proteins involved in starvation-satiety processes, activate the brown adipose tissue, decrease lipogenesis and inflammation, increase lipolysis, and improve insulin sensitivity. This review provides a comprehensive view of nature-based therapeutic options to address the increasing prevalence of obesity. It offers a valuable perspective for future research and subsequent clinical practice, addressing everything from the molecular, genetic, and physiological bases to the clinical study of bioactive compounds.

Butyric Acid Supplementation Reduces Changes in the Taxonomic and Functional Composition of Gut Microbiota Caused by H. pylori Eradication Therapy

H. pylori eradication therapy leads to significant changes in the gut microbiome, including influence on the gut microbiome's functional potential. Probiotics are one of the most studied potential methods for reducing the microbiota-related consequences of antibiotics. However, the beneficial effects of probiotics are still under discussion. In addition, there are some concerns about the safety of probiotics, emphasizing the need for research of other therapeutic interventions. The aim of our study was to evaluate the influence of butyric acid+inulin supplements on gut microbiota changes (the gut microbiota composition, abundance of metabolic pathways, and gut resistome) caused by H. pylori eradication therapy.

MATERIALS AND METHODS

Twenty two H. pylori-positive patients, aged 19 to 64 years, were enrolled in the study and randomized into two treatment groups, as follows: (1) ECAB-14 (n = 11), with esomeprazole 20 mg, clarithromycin 500 mg, amoxicillin 1000 mg, and bismuthate tripotassium dicitrate 240 mg, twice daily, per os, for 14 days, and (2), ECAB-Z-14 (n = 11), with esomeprazole 20 mg, clarithromycin 500 mg, amoxicillin 1000 mg, and bismuthate tripotassium dicitrate 240 mg, twice daily, along with butyric acid+inulin (Zacofalk), two tablets daily, each containing 250 mg of butyric acid, and 250 mg of inulin, per os, for 14 days. Fecal samples were collected from each subject prior to eradication therapy (time point I), after the end of eradication therapy (time point II), and a month after the end of eradication therapy (time point III). The total DNA from the fecal samples was isolated for whole genome sequencing using the Illumina NextSeq 500 platform. Qualitative and quantitative changes in gut microbiota were assessed, including alpha and beta diversity, functional potential and antibiotic resistance gene profiling.

RESULTS

Gut microbiota alpha diversity significantly decreased compared with the baseline immediately after eradication therapy in both treatment groups (ECAB-14 and ECAB-Z-14). This diversity reached its baseline in the ECAB-Z-14 treatment group a month after the end of eradication therapy. However, in the ECAB-14 treatment arm, a reduction in the Shannon index was observed up to a month after the end of H. pylori eradication therapy. Fewer alterations in the gut microbiota functional potential were observed in the ECAB-Z-14 treatment group. The abundance of genes responsible for the metabolic pathway associated with butyrate production decreased only in the ECAB-14 treatment group. The prevalence of antibiotic-resistant genes in the gut microbiota increased significantly in both treatment groups by the end of treatment. However, more severe alterations were noted in the ECAB-14 treatment group.

CONCLUSIONS

H. pylori eradication therapy leads to taxonomic changes, a reduction in the alpha diversity index, and alterations in the functional potential of the gut microbiota and gut resistome. Taking butyric acid+inulin supplements during H. pylori eradication therapy could help maintain the gut microbiota in its initial state and facilitate its recovery after H. pylori eradication.

Gut microbiota dynamics interacting with gastrointestinal evacuation of Apostichopus japonicus: novel insights into promising strategies for environmental improvement

As an important input of environmental micropollutants into aquaculture environment, feed is now considered to be a critical factor in shaping gastrointestinal evacuation characteristics of animals. We analyzed the gastrointestinal evacuation characteristics and gut bacteria of Apostichopus japonicus within 30 h after feeding in recirculating aquaculture system (RAS) and explored the evacuation mechanism interacting by bacteria. The Gauss model was the most precise gastrointestinal evacuation curve, and 80% of gastrointestinal evacuation time was 27.81 h after feeding. Linear discriminant analysis effect size analysis revealed that gut microbial abundance associated significantly with time (P < 0.05), and 42 biomarkers that could predict gastrointestinal evacuation were totally detected, such as Lutibacter and Vibrio. Biomarkers at 25 h after feeding were related to harmful bacteria. A dynamic response between gastrointestinal content ratio and gut microbial abundance was detected. Taken together, we could discharge sewage about 25 h after feeding and carry out the next round of feeding activities.

Oral Cardiac Drug-Gut Microbiota Interaction in Chronic Heart Failure Patients: An Emerging Association

Regardless of the currently proposed best medical treatment for heart failure patients, the morbidity and mortality rates remain high. This is due to several reasons, including the interaction between oral cardiac drug administration and gut microbiota. The relation between drugs (especially antibiotics) and gut microbiota is well established, but it is also known that more than 24% of non-antibiotic drugs affect gut microbiota, altering the microbe's environment and its metabolic products. Heart failure treatment lies mainly in the blockage of neuro-humoral hyper-activation. There is debate as to whether the administration of heart-failure-specific drugs can totally block this hyper-activation, or whether the so-called intestinal dysbiosis that is commonly observed in this group of patients can affect their action. Although there are several reports indicating a strong relation between drug-gut microbiota interplay, little is known about this relation to oral cardiac drugs in chronic heart failure. In this review, we review the contemporary data on a topic that is in its infancy. We aim to produce scientific thoughts and questions and provide reasoning for further clinical investigation.

Bioactives and their roles in bone metabolism of osteoarthritis: evidence and mechanisms on gut-bone axis

Bioactives significantly modify and maintain human health. Available data suggest that Bioactives might play a beneficial role in chronic inflammatory diseases. Although promised, defining their mechanisms and opting to weigh their benefits and limitations is imperative. Detailed mechanisms by which critical Bioactives, including probiotics and prebiotics such as dietary lipids (DHA, EPA, alpha LA), vitamin D, polysaccharides (fructooligosaccharide), polyphenols (curcumin, resveratrol, and capsaicin) potentially modulate inflammation and bone metabolism is limited. Certain dietary bioactive significantly impact the gut microbiota, immune system, and pain response via the gut-immune-bone axis. This narrative review highlights a recent update on mechanistic evidence that bioactive is demonstrated demonstrated to reduce osteoarthritis pathophysiology.

The Rosetta Stone of interactions of mucosa and associated bacteria in the gastrointestinal tract

PURPOSE OF REVIEW

Gut microbiota-mucosa-epithelial cells co-exist in an intricate three-way relationship that underpins gut homeostasis, and ultimately influences health and disease conditions. The O-glycans of mucin glycoproteins have been uncovered as a centrepiece of this system, although understanding the phenomena at play at the molecular level has been challenging and subject to significant traction over the last years. The purpose of this review is to discuss the recent advances in the phenomena that mediate microbiota and mucus multidirectional interactions in the human gut.

RECENT FINDINGS

The mucus biosynthesis and degradation by both commensal and pathogenic bacteria is under tight regulation and involves hundreds of carbohydrate-active enzymes (CAZy) and transporters. The fucosylation of O-glycans from mucin-2 seems to dictate binding by pathogenic species and to influence their virulence. Less clear is the influence of O-glycans in quorum sensing and biofilm formation. We have reviewed the advances in the in vitro models available to recreate the phenomena that capture the physiological context of the intestinal environment, emphasising models that include mucus and other aspects relevant to the physiological context.

SUMMARY

The recent findings highlight the importance of merging advances in analytical (glycans analysis) and omics techniques along with original robust in vitro models that enable to deconstruct part of the high complexity of the living gut and expand our understanding of the microbes-mucosa relationships and their significance in health and disease.

Single-Cell Hemoprotein Diet Changes Adipose Tissue Distributions and Re-Shapes Gut Microbiota in High-Fat Diet-Induced Obese Mice

We have previously observed that feeding with single-cell hemoprotein (heme-SCP) in dogs (1 g/day for 6 days) and broiler chickens (1 ppm for 32 days) increased the proportion of lactic acid bacteria in the gut while reducing their body weights by approximately 1~2%. To define the roles of heme-SCP in modulating body weight and gut microbiota, obese C57BL/6N mice were administered varied heme-SCP concentrations (0, 0.05, and 0.5% heme-SCP in high fat diet) for 28 days. The heme-SCP diet seemed to restrain weight gain till day 14, but the mice gained weight again later, showing no significant differences in weight. However, the heme-SCP-fed mice had stiffer and oilier bodies compared with those of the control mice, which had flabby bodies and dull coats. When mice were dissected at day 10, the obese mice fed with heme-SCP exhibited a reduction in subcutaneous fat with an increase in muscle mass. The effect of heme-SCP on the obesity-associated dyslipidemia tended to be corroborated by the blood parameters (triglyceride, total cholesterol, and C-reactive protein) at day 10, though the correlation was not clear at day 28. Notably, the heme-SCP diet altered gut microbiota, leading to the proliferation of known anti-obesity biomarkers such as Akkermansia, Alistipes, Oscillibacter, Ruminococcus, Roseburia, and Faecalibacterium. This study suggests the potential of heme-SCP as an anti-obesity supplement, which modulates serum biochemistry and gut microbiota in high-fat diet-induced obese mice.

The Impact of Chronic Stress Related to COVID-19 on Eating Behaviors and the Risk of Obesity in Children and Adolescents

During the COVID-19 pandemic, an increase in the incidence of overweight and obesity in children was observed. It appears that unhealthy food choices, an unbalanced diet, and a sedentary lifestyle, as well as experiencing stress related to the pandemic, may be contributing to this disturbing trend. Chronic stress is a significant factor contributing to eating disorders and obesity in youngsters, involving medical, molecular, and psychological elements. Individuals under chronic stress often focus on appearance and weight, leading to negative body image and disrupted relationships with food, resulting in unhealthy eating behaviors. Chronic stress also impacts hormonal balance, reducing the satiety hormone leptin and elevating the appetite-stimulating hormone ghrelin, fostering increased hunger and uncontrolled snacking. Two systems, the hypothalamic-pituitary-adrenal axis and the sympathetic system with the adrenal medulla, are activated in response to stress, causing impaired secretion of noradrenaline and cortisol. Stress-related obesity mechanisms encompass oxidative stress, neuroinflammation, insulin resistance, and neurohormonal and neurotransmission disorders. Stress induces insulin resistance, elevating obesity risk by disrupting blood sugar regulation and fat storage. Stress also affects the gut microbiome, potentially influencing chronic inflammation and metabolic processes linked to obesity. In conclusion, chronic stress is a multifaceted risk factor for eating disorders and obesity in children, necessitating a comprehensive understanding of effective preventive and intervention strategies amid the escalating prevalence of childhood overweight and obesity.

Pediococcus acidilactici (pA1c®) alleviates obesity-related dyslipidemia and inflammation in Wistar rats by activating beta-oxidation and modulating the gut microbiota

Due to the importance of the gut microbiota in the regulation of energy homeostasis, probiotics have emerged as an alternative therapy to ameliorate obesity-related disturbances, including cholesterol metabolism dysregulation, dyslipidemia and inflammation. Therefore, the objectives of this study were to evaluate the effect of the probiotic strain Pediococcus acidilactici (pA1c®) on the regulation of adiposity, cholesterol and lipid metabolism, inflammatory markers and gut microbiota composition in diet-induced obese rats. Twenty-nine four-week-old male Wistar rats were divided into three groups: rats fed a control diet (CNT group, n = 8), rats fed a high fat/high sucrose diet (HFS group, n = 11), and rats fed a HFS diet supplemented with pA1c® (pA1c®group, n = 10). Organs and fat depots were weighed, and different biochemical parameters were analysed in serum. Gene expression analyses in the adipose tissue were conducted using real-time quantitative-PCR. Faecal microbiota composition was evaluated using 16S metagenomics. Animals supplemented with pA1c® exhibited a lower proportion of visceral adiposity, a higher proportion of muscle, an improvement in the total-cholesterol/HDL-cholesterol ratio and a decrease in the total cholesterol, triglyceride and aspartate aminotransaminase (AST) serum levels, together with a decrease in several inflammation-related molecules. The expression of key genes related to adipose (Adipoq, Cebpa and Pparg) and glucose (Slc2a1 and Slc2a4) metabolism in the adipose tissue was normalized by pA1c®. Moreover, it was demonstrated that pA1c® supplementation activated fatty acid β-oxidation in the adipose tissue and the liver. Metagenomics demonstrated the presence of pA1c® in the faecal samples, an increase in alpha diversity, an increase in the abundance of beneficial bacteria, and a decrease in the abundance of harmful micro-organisms, including the Streptococcus genus. Thus, our data suggest the potential of pA1c® in the prevention of obesity-related disturbances including hypercholesterolemia, hypertriglyceridemia, inflammation and gut microbiota dysbiosis.

Metabolic Syndrome: A Narrative Review from the Oxidative Stress to the Management of Related Diseases

Metabolic syndrome (MS) is a growing disorder affecting thousands of people worldwide, especially in industrialised countries, increasing mortality. Oxidative stress, hyperglycaemia, insulin resistance, inflammation, dysbiosis, abdominal obesity, atherogenic dyslipidaemia and hypertension are important factors linked to MS clusters of different pathologies, such as diabesity, cardiovascular diseases and neurological disorders. All biochemical changes observed in MS, such as dysregulation in the glucose and lipid metabolism, immune response, endothelial cell function and intestinal microbiota, promote pathological bridges between metabolic syndrome, diabesity and cardiovascular and neurodegenerative disorders. This review aims to summarise metabolic syndrome's involvement in diabesity and highlight the link between MS and cardiovascular and neurological diseases. A better understanding of MS could promote a novel strategic approach to reduce MS comorbidities.

Improvement in Cutaneous Conditions Can Benefit Some Health Conditions in the Elderly

As we are aging, a number of cutaneous and extracutaneous disorders will be developed. Although the pathogenesis of these aging-associated disorders is not clear yet, abnormalities in the skin are linked to some aging-associated disorders at least to some extent. Inflammatory dermatoses such as psoriasis and atopic dermatitis predispose to the development of cardiovascular diseases, obesity and type 2 diabetes. In addition, both chronologically aged skin and individuals with some aging-associated systemic conditions display altered epidermal function, such as reduced stratum corneum hydration levels, which can provoke cutaneous inflammation. Because aged skin exhibits higher expression levels of inflammatory cytokines, which play a pathogenic role in a variety of aging-associated health condition, the association of the skin with some aging-associated disorders is likely mediated by inflammation. This postulation is supported by the evidence that improvement in either epidermal function or inflammatory dermatoses can mitigate some aging-associated disorders such as mild cognitive impairment and insulin sensitivity. This perspective discusses the association of the skin with aging-associated disorders and highlights the potential of improvement in cutaneous conditions in the management of some health conditions in the elderly.

Short-term use of ceftriaxone sodium leads to intestinal barrier disruption and ultrastructural changes of kidney in SD rats

OBJECTIVE

Antibiotic treatments are known to disturb gut microbiota, but their effects on the mucosal barrier and extraintestinal diseases are rarely discussed. The aim of this study was to evaluate and visualize the impact of antibiotics on colonic mucus and the microbial community, and to assess whether intestinal dysbacteriosis is involved in the pathogenesis and progression of extraintestinal diseases in vivo.

MATERIALS AND METHODS

Twenty-one SD rats were randomly assigned into three groups followed by different experimental treatments. The albumin-creatinine ratio, urinary protein and occult blood semi-quantified test were tested. Fecal samples were collected at different time points (0,4, and 12 weeks) for 16S rRNA gene sequencing. Colon and kidney specimens were examined using light microscopy and transmission electron microscopy (TEM) to identify morphological changes.

RESULTS

Ceftriaxone intervention for one week did not cause any symptoms of diarrhea or weight loss, but the alpha and beta diversities of gut microbiota decreased quickly and significantly, a lower Firmicutes/Bacteroidetes (F/B) ratio was observed. At week 12, although the alpha and beta diversities increased to a level similar to that of the control (CON) group, LEfSe analysis indicated that the microbial community composition still differed significantly in each group. In addition, KEGG metabolic prediction revealed different metabolic functions in each group. TEM examination of colon revealed that dramatic morphological changes were observed in the ceftriaxone (Cef) group, wherein microvilli were misaligned and shortened significantly and morphologically intact bacteria were seen on the epithelial cell surface. TEM examination of kidneys from the Cef group showed characteristic glomerular changes in the form of widely irregularly thickened glomerular basement membrane (GBM) and foot process fusion or effacement; mild thickening of the GBM and foot process fusion was detected when ceftriaxone and Resatorvid (TAK242, an inhibitor of TLR4 signaling) are used together in the ceftriaxone + TAK242 (TAK) group.

CONCLUSIONS

Short-term use of ceftriaxone induced dynamic changes of gut microbiota and lead to intestinal barrier disruption and ultrastructural changes of kidneys in the SD rats. Moreover, interference with the TLR4-dependent signaling pathway can alleviate the damage to the intestinal barrier and kidney.

Why Does Your Uterus Become Malignant? The Impact of the Microbiome on Endometrial Carcinogenesis

The aim of this review was to describe the uterine microbiome composition that has been analyzed so far and describe potential pathways in the carcinogenesis of the endometrium. The microbiome in the uterine environment is involved in apoptosis and proliferation during the menstruation cycle, pregnancy maintenance, and immune system support. However, bacteria in the uterus could stimulate inflammation, which when chronic results in malignancy. An altered gut microbiota initiates an inflammatory response through microorganism-associated molecular patterns, which leads to intensified steroidogenesis in the ovaries and cancers. Moreover, intestinal bacteria secreting the enzyme β-glucuronidase may increase the level of circulating estrogen and, as a result, be influential in gynecological cancers. Both the uterine and the gut microbiota play a pivotal role in immune modulation, which is why there is a demand for further investigation from both the diagnostic and the therapeutic perspectives.

The gut microbiome in the fight against obesity: The potential of dietary factors

Obesity as a global public health burden has experienced a drastic growing trend recently. The management of obesity is challenging because of its complex etiology, and various factors are involved in its development, such as genetic and environmental factors. Different approaches are available to treat and/or manage obesity, including diet, physical activity, lifestyle changes, medications, and surgery. However, some of these approaches have inherent limitations and are closely associated with adverse effects. Therefore, probing into a novel/safe approach to treat and/or manage obesity is of fundamental importance. One such approach gaining renewed interest is the potential role of gut microbiota in obesity and its effectiveness in treating this condition. However, there is a dearth of comprehensive compilation of data on the potential role of the gut microbiome in obesity, particularly regarding dietary factors as a therapeutic approach. Therefore, this review aims to provide an updated overview of the role of gut microbiota in obesity, further highlighting the importance of dietary factors, particularly diet, prebiotics, and probiotics, as potential complementary and/or alternative therapeutic options. Moreover, the association of gut microbiota with obese or lean individuals has also been discussed.

The epithelial barrier: The gateway to allergic, autoimmune, and metabolic diseases and chronic neuropsychiatric conditions

Since the 1960 s, our health has been compromised by exposure to over 350,000 newly introduced toxic substances, contributing to the current pandemic in allergic, autoimmune and metabolic diseases. The "Epithelial Barrier Theory" postulates that these diseases are exacerbated by persistent periepithelial inflammation (epithelitis) triggered by exposure to a wide range of epithelial barrier-damaging substances as well as genetic susceptibility. The epithelial barrier serves as the body's primary physical, chemical, and immunological barrier against external stimuli. A leaky epithelial barrier facilitates the translocation of the microbiome from the surface of the afflicted tissues to interepithelial and even deeper subepithelial locations. In turn, opportunistic bacterial colonization, microbiota dysbiosis, local inflammation and impaired tissue regeneration and remodelling follow. Migration of inflammatory cells to susceptible tissues contributes to damage and inflammation, initiating and aggravating many chronic inflammatory diseases. The objective of this review is to highlight and evaluate recent studies on epithelial physiology and its role in the pathogenesis of chronic diseases in light of the epithelial barrier theory.

Berberine interacts with gut microbiota and its potential therapy for polycystic ovary syndrome

Berberine (BBR) is an isoquinoline alkaloid extracted from Chinese medicinal plants showing a tight correlation with gut microbiota. Polycystic ovary syndrome (PCOS) is a prevalent reproductive and endocrine disorder syndrome among women of childbearing age. Dysbiosis, the imbalance of intestinal microorganisms, is a potential factor that takes part in the pathogenesis of PCOS. Recent evidence indicates that berberine offers promise for treating PCOS. Here, we review the recent research on the interaction between berberine and intestinal microorganisms, including the changes in the structure of gut bacteria, the intestinal metabolites after BBR treatment, and the effect of gut microbiota on the bioavailability of BBR. We also discuss the therapeutic effect of BBR on PCOS in terms of gut microbiota and its potential mechanisms.

Eight Weeks of Bifidobacterium lactis BL-99 Supplementation Improves Lipid Metabolism and Sports Performance through Short-Chain Fatty Acids in Cross-Country Skiers: A Preliminary Study

(1) Background: Probiotics in the form of nutritional supplements are safe and potentially useful for strategic application among endurance athletes. Bifidobacterium animalis lactis BL-99 (BL-99) was isolated from the intestines of healthy Chinese infants. We combined plasma-targeted metabolomics and fecal metagenomics to explore the effect of 8 weeks of BL-99 supplementation on cross-country skiers' metabolism and sports performance. (2) Methods: Sixteen national top-level male cross-country skiers were recruited and randomly divided into a placebo group (C) and a BL-99 group (E). The participants took the supplements four times/day (with each of three meals and at 21:00) consistently for 8 weeks. The experiment was conducted in a single-blind randomized fashion. The subject's dietary intake and total daily energy consumption were recorded. Blood and stool samples were collected before and after the 8-week intervention, and body composition, muscle strength, blood biochemical parameters, plasma-targeted metabolomic data, and fecal metagenomic data were then analyzed. (3) Results: The following changes occurred after 8 weeks of BL-99 supplementation: (a) There was no significant difference in the average total daily energy consumption and body composition between the C and E groups. (b) The VO2max and 60°/s and 180°/s knee joint extensor strength significantly increased in both the C and E groups. By the eighth week, the VO2max and 60 s knee-joint extensor strength were significantly higher in the E group than in the C group. (c) The triglyceride levels significantly decreased in both the C and E groups. In addition, the LDL-C levels significantly decreased in the E group. (d) The abundance of Bifidobacterium animalis increased two-fold in the C group and forty-fold in the E group. (e) Plasma-targeted metabolomic analysis showed that, after eight weeks of BL-99 supplementation, the increases in DHA, adrenic acid, linoleic acid, and acetic acid and decreases in glycocholic acid and glycodeoxycholic acid in the E group were significantly higher than those in the C group. (f) Spearman correlation analysis showed that there was a significant positive correlation between Bifidobacterium animalis' abundance and SCFAs, PUFAs, and bile acids. (g) There was a significant correlation between the most significantly regulated metabolites and indicators related to sports performance and lipid metabolism. (4) Conclusions: Eight weeks of BL-99 supplementation combined with training may help to improve lipid metabolism and sports performance by increasing the abundance of Bifidobacterium, which can promote the generation of short-chain fatty acids and unsaturated fatty acids, and inhibit the synthesis of bile acids.

Targeting gut-liver axis by dietary lignans ameliorate obesity: evidences and mechanisms

An imbalance between energy consumption and energy expenditure causes obesity. It is characterized by increased adipose accumulation and accompanied by chronic low-grade inflammation. Many studies have suggested that the gut microbiota of the host mediates the relationship between high-fat diet consumption and the development of obesity. Diet and nutrition of the body are heavily influenced by gut microbiota. The alterations in the microbiota in the gut may have effects on the homeostasis of the host's energy levels, systemic inflammation, lipid metabolism, and insulin sensitivity. The liver is an important organ for fat metabolism and gut-liver axis play important role in the fat metabolism. Gut-liver axis is a bidirectional relationship between the gut and its microbiota and the liver. As essential plant components, lignans have been shown to have different biological functions. Accumulating evidences have suggested that lignans may have lipid-lowering properties. Lignans can regulate the level of the gut microbiota and their metabolites in the host, thereby affecting signaling pathways related to fat synthesis and metabolism. These signaling pathways can make a difference in inhibiting fat accumulation, accelerating energy metabolism, affecting appetite, and inhibiting chronic inflammation. It will provide the groundwork for future studies on the lipid-lowering impact of lignans and the creation of functional meals based on those findings.

Mediterranean diet and olive oil, microbiota, and obesity-related cancers. From mechanisms to prevention

Olive oil (OO) is the main source of added fat in the Mediterranean diet (MD). It is a mix of bioactive compounds, including monounsaturated fatty acids, phytosterols, simple phenols, secoiridoids, flavonoids, and terpenoids. There is a growing body of evidence that MD and OO improve obesity-related factors. In addition, obesity has been associated with an increased risk for several cancers: endometrial, oesophageal adenocarcinoma, renal, pancreatic, hepatocellular, gastric cardia, meningioma, multiple myeloma, colorectal, postmenopausal breast, ovarian, gallbladder, and thyroid cancer. However, the epidemiological evidence linking MD and OO with these obesity-related cancers, and their potential mechanisms of action, especially those involving the gut microbiota, are not clearly described or understood. The goals of this review are 1) to update the current epidemiological knowledge on the associations between MD and OO consumption and obesity-related cancers, 2) to identify the gut microbiota mechanisms involved in obesity-related cancers, and 3) to report the effects of MD and OO on these mechanisms.

Neuroinflammation: A Modifiable Pathway Linking Obesity, Alzheimer's disease, and Depression

Obesity, depression and Alzheimer's disease (AD) are three major interrelated modern health conditions with complex relationships. Early-life depression may serve as a risk factor for AD, while late-life depression may be a prodrome of AD. Depression affects approximately 23% of obese individuals, and depression itself raises the risk of obesity by 37%. Mid-life obesity independently increases AD risk, while late-life obesity, particularly metabolically healthy obesity, may offer protection against AD pathology. Chronic inflammation serves as a key mechanism linking obesity, AD, and depression, encompassing systemic inflammation from metabolic disturbances, immune dysregulation through the gut microbiome, and direct interactions with amyloid pathology and neuroinflammation. In this review, we explore the biological mechanisms of neuroinflammation in relation to obesity, AD, and depression. We assess the efficacy of therapeutic interventions targeting neuroinflammation and discuss current and future radiological imaging initiatives for studying neuroinflammation. By comprehending the intricate interplay among depression, obesity, and AD, especially the role of neuroinflammation, we can advance our understanding and develop innovative strategies for prevention and treatment.

The impact of MIF deficiency on alterations of fecal microbiota in C57BL/6 mice induced by Trichinella spiralis infection

Trichinellosis caused by Trichinella spiralis (T. spiralis) is a major food-borne parasitic zoonosis worldwide. Prevention of trichinellosis is an effective strategy to improve patient quality of life. Macrophage migration inhibitory factor (MIF) is closely related to the occurrence and development of several parasitic diseases. Studying the impact of MIF deficiency (Mif-/- ) on the alterations in host fecal microbiota due to T. spiralis infection may contribute to proposing a novel dual therapeutic approach for trichinellosis. To reveal the diversity and differences in fecal microbial composition, feces were collected from T. spiralis-uninfected and T. spiralis-infected wild-type (WT) and MIF knockout (KO) C57BL/6 mice at 0, 7, 14, and 35 days post-infection (dpi), and the samples were sent for 16S rRNA amplicon sequencing on the Illumina NovaSeq platform. Flow cytometry was used to determine the expression levels of IFN-γ and IL-4 in the CD4+ /CD8+  T-cell sets of mouse spleens. The results showed that operational taxonomic unit (OTU) clustering, relative abundance of microbial composition, alpha diversity, and beta diversity exhibited significant changes among the eight groups. The LEfSe analysis selected several potential biomarkers at the genus or species level, including Akkermansia muciniphila, Lactobacillus murinus, Coprococcus catus, Firmicutes bacterium M10_2, Parabacteroides sp. CT06, and Bacteroides between the KTs and WTs groups. The predicted bacterial functions of the fecal microbiota were mainly involved in metabolism, such as the metabolism of carbohydrates, amino acids, energy, cofactors, vitamins, nucleotides, glycans, and lipids. Flow cytometry revealed an increased CD3+ CD8- /CD3+ CD8+  T-cell ratio and increased IFN-γ and IL-4 levels in CD3+ CD8- T-cell sets from WT and MIF KO mice at 7 dpi. The results indicated that both MIF KO and infection time have a significant influence on the CD3+ CD8- IFN-γ+ and CD3+ CD8- IL-4+ response in mice after T. spiralis. In conclusion, this research showed alterations of the fecal microbiota and immune response in both WT and MIF KO mice before and after T. spiralis infection. These results revealed a potential role of MIF in regulating the pathogenesis of trichinellosis related to the intestinal microbiota. Importantly, the selected potential biomarkers combined with MIF will also offer a novel therapeutic approach to treat trichinellosis in the future.

The Effects of Dietary Chromium Supplementation along with Discontinuing a High-Fat Diet on the Microbial Enzymatic Activity and the Production of SCFAs in the Faeces of Rats

The present study assessed the changes in faecal microbial activity in obese Wistar rats fed high-fat or low-fat diets supplemented with various forms of chromium (picolinate or nanoparticles). The 18-week study was divided into two phases: an introductory period (9 weeks; obesity status induction via a high-fat diet) and an experimental period (9 weeks; maintained on a high-fat diet or switched to a low-fat diet and Cr supplementation). During the experimental period (10-18 weeks of feeding), samples of fresh faeces were collected on chosen days. The bacterial enzymatic activity and short-chain fatty acids (SCFAs) concentration were assessed to characterise the dynamism of the changes in faecal microbial metabolic activity under the applied dietary treatments. The results indicated that faecal microbial metabolic activity displayed several adaptation mechanisms in response to modifications in dietary conditions, and a beneficial outcome resulted from a pro-healthy dietary habit change, that is, switching from a high-fat to a low-fat diet. Dietary supplementation with chromium nanoparticles further modulated the aforementioned microbial activity, i.e., diminished the extracellular and total enzymatic activities, while the effect of chromium picolinate addition was negligible. Both the high-fat diet and the addition of chromium nanoparticles reduced SCFA concentrations and increased the faecal pH values.

Prebiotic effect of poly-D-3-hydroxybutyrate prevents dyslipidemia in obese mice

Obesity is a global health problem caused by genetic, environmental, and psychological factors and is associated with various health disorders. As such, there is a growing focus on the prevention of obesity and related diseases. The gut microbiota plays a crucial role in these diseases and has become a therapeutic target. Prebiotics, such as poly-d-3-hydroxybutyric acid (PHB), have gained attention for their potential to alter the gut microbiota, promote beneficial bacterial growth, and alleviate obesity. In this study, we examined the prebiotic effects of PHB in obese mice. We found that, in C57BL/6N mice, PHB reduced blood lipid levels. Analysis of the intestinal microflora also revealed an increase in short-chain fatty acid-producing bacteria. When PHB was administered to obese mice, subcutaneous fat and dyslipidemia were reduced, and the number of beneficial bacteria in the intestinal microflora increased. Furthermore, fatty degradation and oxidative stress were suppressed in the liver. PHB regulates gut bacterial changes related to obesity and effectively inhibits dyslipidemia, suggesting that it could be a prebiotic agent for curing various obesity-related diseases. In summary, PHB increases the beneficial gut microbiota, leading to an alleviation of obesity-associated dyslipidemia.

Fecal Microbiota Transplantation from Aged Mice Render Recipient Mice Resistant to MPTP-Induced Nigrostriatal Degeneration Via a Neurogenesis-Dependent but Inflammation-Independent Manner

Accumulating data support a crucial role of gut microbiota in Parkinson's disease (PD). However, gut microbiota vary with age and, thus, will affect PD in an age-dependent, but unknown manner. We examined the effects of fecal microbiota transplantation (FMT) pretreatment, using fecal microbiota from young (7 weeks) or aged mice (23 months), on MPTP-induced PD model. Motor function, pathological changes, striatal neurotransmitters, neuroinflammation, gut inflammation and gut permeability were examined. Gut microbiota composition and metabolites, namely short-chain fatty acids (SCFAs), were analyzed. Neurogenesis was also evaluated by measuring the number of doublecortin-positive (DCX+) neurons and Ki67-positive (Ki67+) cells in the hippocampus. Expression of Cd133 mRNA, a cellular stemness marker, in the hippocampus was also examined. Mice who received FMT from young mice showed MPTP-induced motor dysfunction, and reduction of striatal dopamine (DA), dopaminergic neurons and striatal tyrosine hydroxylase (TH) levels. Interestingly and unexpectedly, mice that received FMT from aged mice showed recovery of motor function and rescue of dopaminergic neurons and striatal 5-hydroxytryptamine (5-HT), as well as decreased DA metabolism after MPTP challenge. Further, they showed improved metabolic profiling and a decreased amount of fecal SCFAs. High-throughput sequencing revealed that FMT remarkably reshaped the gut microbiota of recipient mice. For instance, levels of genus Akkermansia and Candidatus Saccharimonas were elevated in fecal samples of recipient mice receiving aged microbiota (AM + MPTP mice) than YM + MPTP mice. Intriguingly, both young microbiota and aged microbiota had no effect on neuroinflammation, gut inflammation or gut permeability. Notably, AM + MPTP mice showed a marked increase in DCX+ neurons, as well as Ki67+ cells and Cd133 expression in the hippocampal dentate gyrus (DG) compared to YM + MPTP mice. These results suggest that FMT from aged mice augments neurogenesis, improves motor function and restores dopaminergic neurons and neurotransmitters in PD model mice, possibly through increasing neurogenesis.

Partially defatted rather than native poppy seeds beneficially alter lipid metabolism in rats fed a high-fat diet

Partially defatted poppy seeds, a by-product of poppy oil cold pressing, could be an interesting dietary supplement for obesity management. The aim of this study was to compare the effects of dietary supplementation with a small amount of native or partially defatted poppy seeds on gastrointestinal function and lipid metabolism in rats fed a high-fat diet. The defatted poppy seeds had, among others, lower fat content and higher fibre and protein content than native poppy seeds. The rats fed with a high-fat diet were characterised by severe metabolic disorders, especially in the liver, and poppy seeds were unable to prevent them. However, depending on the seed form, dietary supplementation with poppy seeds differentially affected the microbial and endogenous lipid metabolism in rats. In the distal intestine, both dietary seed forms stimulated microbial acetate production, and the supplementation with partially defatted poppy seeds additionally inhibited isobutyrate and isovalerate formation, which indicates a reduction in putrefaction. Both dietary seed forms increased cholesterol accumulation in the liver. Only dietary supplementation with partially defatted poppy seeds attenuated visceral fat and hepatic triglyceride accumulations and lowered blood triglyceride concentrations, and at the transcriptional level, the inhibition of SREBP-1c, which upregulates genes responsible for de novo lipogenesis, was additionally observed in this organ. In conclusion, a low and regular consumption of partially defatted poppy seeds may be beneficial in managing obesity-related disorders.

Associations of Adherence to the 2018 World Cancer Research Fund and the American Institute for Cancer Research Dietary Recommendations with Gut Microbiota and Inflammation Levels

BACKGROUND

Whether the World Cancer Research Fund and the American Institute for Cancer Research (WCRF/AICR) dietary recommendations affect the gut microbiota and inflammatory status remains unclear. We examined the association of dietary adherence scores to the WCRF/AICR with gut microbiota and inflammation in a cross-sectional setting.

METHODS

The WCRF/AICR diet adherence scores were calculated for 151 participants (adenoma 97, non-adenoma 54) from 7-day dietary records. The gut microbiota was analyzed by 16S rRNA gene sequencing of fecal samples. The levels of inflammatory biomarkers in both blood (i.e., IL-6, IL-8, IgA, IgM, and IgG) and fecal samples (i.e., FCP) were evaluated in 97 colorectal adenoma patients who had blood samples available. Multivariable linear regression analyses were conducted to examine the association of individual and total dietary adherence scores with gut microbiota and inflammatory biomarker levels.

RESULTS

Participants with higher adherence had lower relative abundance of Proteobacteria (β = -0.041, 95%CI: -0.073, -0.009), Enterobacteriaceae (β = -0.035, 95%CI: -0.067, -0.003), and unidentified Enterobacteriaceae at the genus level (β = -0.029, 95%CI: -0.055, -0.003) compared to those with lower adherence. Plant-based food intake was positively correlated with increased abundance of Phascolarctobacterium (β = 0.013, 95%CI: 0.001, 0.026). Restricting fast food was linked to high abundance of Bacteroidaceae (β = 0.149, 95%CI: 0.040, 0.257) and Bacteroides (β = 0.149, 95%CI: 0.040, 0.257). Limiting sugary drinks was associated with reduced abundance of Lachnospiraceae (β = -0.155, 95%CI: -0.292, -0.018). Plant-based food intake (β = -0.251, 95%CI: -0.450, -0.052) and restriction of fast food (β = -0.226, 95%CI: -0.443, -0.008) were associated with reduced IGG levels in men. Alcohol restriction was linked to lower IL-6 (β = -7.095, 95%CI: -11.286, -2.903) and IL-8 (β = -7.965, 95%CI: -14.700, -1.230) levels in women, but with higher IL-6 (β = 0.918, 95%CI: 0.161, 1.675) levels in men.

CONCLUSIONS

Our findings support the association of adherence to the WCRF/AICR diet with gut microbiota and inflammation. These results need to be validated in additional prospective or interventional studies.

A multicenter double-blind, placebo-controlled randomized trial to evaluate the safety and efficacy of bovine colostrum in the treatment of severe alcoholic hepatitis (SAH)

BACKGROUND

Severe alcoholic hepatitis (SAH) is associated with high mortality. Numerous studies and meta-analysis have reported that corticosteroids reduce the 28-day mortality in SAH, but not the 6-month mortality. Therefore, newer treatments for SAH need to be studied. A pilot study from our group had recently treated ten patients with SAH with bovine colostrum (BC) [20 g thrice in a day for 8 weeks] and prednisolone. This therapy improved the biological functions and 3-month mortality. However, as more and more data showed the failure of corticosteroids to improve the 3- and 6-month mortality, especially in patients with high mDF and MELD scores, we planned this trial to study the safety and efficacy of BC (without corticosteroids) in the treatment of SAH.

METHOD

This is a multicenter, parallel, double-blind, randomized (1:1) placebo-controlled trial, which will enroll 174 patients with SAH from 5 academic centers in the India. Patients will receive freeze-dried BC or placebo by random 1:1 allocation for 4 weeks. The primary outcome measure is survival at 3 months. The secondary outcome measures are survival at 1 month, change in mDF and MELD scores, change in endotoxin and cytokines (alpha TNF, IL6, and IL8) levels, number of episodes of sepsis [pneumonia, spontaneous bacterial peritonitis (SBP), cellulitis, urinary tract infection (UTI)] from baseline to 4 weeks.

DISCUSSION

This study will evaluate the safety and efficacy of bovine colostrum in improving the survival of patients with SAH.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02473341. Prospectively registered on June 16, 2015.

Gut microbiota in heart failure and related interventions

Heart failure (HF) is a sophisticated syndrome with structural or functional impairment of ventricular filling or ejection of blood, either causing symptoms and signs or being asymptomatic. HF is a major global health issue affecting about 64.3 million people worldwide. The gut microbiota refers to the complex ecosystem of microorganisms, mainly bacteria, in the gut. Studies have revealed that the gut microbiota is associated with many diseases ranging from neurodegenerative diseases to inflammatory bowel disease and cardiovascular diseases. The gut hypothesis of HF suggests that low cardiac output and systemic circulation congestion would cause insufficient intestinal perfusion, leading to ischemia and intestinal barrier dysfunction. The resulting bacterial translocation would contribute to inflammation. Recent studies have refined the hypothesis that changes of metabolites in the gut microbiota have a close relationship with HF. Thus, the gut microbiota has emerged as a potential therapeutic target for HF due to both its critical role in regulating host physiology and metabolism and its pivotal role in the development of HF. This review article aims to provide an overview of the current understanding of the gut microbiota's involvement in HF, including the introduction of the gut hypothesis of HF, its association with HF progression, the potential mechanisms involved mediated by the gut microbiota metabolites, and the impact of various interventions on the gut microbiota, including dietary interventions, probiotic therapy, fecal microbiota transplantation, antibiotics, and so on. While the gut hypothesis of HF is refined with up-to-date knowledge and the gut microbiota presents a promising target for HF therapy, further research is still needed to further understand the underlying mechanisms between gut microbiota and HF, the efficacy of these interventions, and contribute to the health of HF patients.

Effect of the oil from the fatty tissues of Crocodylus siamensis on gut microbiome diversity and metabolism in mice

Dietary fat can alter host metabolism and gut microbial composition. Crocodile oil (CO) was extracted from the fatty tissues of Crocodylus siamensis. CO, rich in monounsaturated- and polyunsaturated fatty acids, has been reported to reduce inflammation, counter toxification, and improve energy metabolism. The aim of this study was to investigate the effect of CO on gut microbiota (GM) in laboratory mice as well as the accompanying metabolic changes in the animals. Forty-five C57BL/6 male mice were randomly divided into five groups and orally administrated either sterile water (control [C]); 1 or 3% (v/w) CO (CO-low [CO-L] and CO-high [CO-H], respectively); or 1 or 3% (v/w) palm oil (PO-low and PO-high, respectively) for 11 weeks. Body weight gain, food intake, energy intake, blood glucose levels, and blood lipid profiles were determined. Samples from colon tissue were collected and the 16S rRNA genes were pyrosequenced to clarify GM analyses. The results showed that there were no differences in body weight and blood glucose levels. Food intake by the mice in the CO-L and CO-H groups was statistically significantly less when compared to that by the animals in the C group. However, neither CO treatment had a statistically significant effect on calorie intake when compared to the controls. The CO-H exhibited a significant increase in serum total cholesterol and low-density lipoprotein but showed a downward trend in triglyceride levels compared to the control. The GM analyses revealed that both CO treatments have no significant influence on bacterial diversity and relative abundance at the phylum level, whereas increases of Choa1 and abundance-based coverage estimator indexes, distinct β-diversity, and Proteobacteria abundance were observed in the PO-high group compared with the C group. Furthermore, the abundance of Azospirillum thiophilum and Romboutsia ilealis was significantly higher in the CO-L and CO-H groups which could be associated with energy metabolic activity. Thus, CO may be an alternative fat source for preserving host metabolism and gut flora.

Gut microbes predominantly act as living beneficial partners rather than raw nutrients

Animals and their gut microbes mutually benefit their health. Nutrition plays a central role in this, directly influencing both host and microbial fitness and the nature of their interactions. This makes nutritional symbioses a complex and dynamic tri-system of diet-microbiota-host. Despite recent discoveries on this field, full control over the interplay among these partners is challenging and hinders the resolution of fundamental questions, such as how to parse the gut microbes' effect as raw nutrition or as symbiotic partners? To tackle this, we made use of the well-characterized Drosophila melanogaster/Lactiplantibacillus plantarum experimental model of nutritional symbiosis to generate a quantitative framework of gut microbes' effect on the host. By coupling experimental assays and Random Forest analysis, we show that the beneficial effect of L. plantarum strains primarily results from the active relationship as symbionts rather than raw nutrients, regardless of the bacterial strain. Metabolomic analysis of both active and inactive bacterial cells further demonstrated the crucial role of the production of beneficial bacterial metabolites, such as N-acetylated-amino-acids, as result of active bacterial growth and function. Altogether, our results provide a ranking and quantification of the main bacterial features contributing to sustain animal growth. We demonstrate that bacterial activity is the predominant and necessary variable involved in bacteria-mediated benefit, followed by strain-specific properties and the nutritional potential of the bacterial cells. This contributes to elucidate the role of beneficial bacteria and probiotics, creating a broad quantitative framework for host-gut microbiome that can be expanded to other model systems.

Aflatoxin B1 Induces Inflammatory Liver Injury via Gut Microbiota in Mice

Aflatoxin B₁ (AFB₁), a potent food-borne hepatocarcinogen, is the most toxic aflatoxin that induces liver injury in humans and animals. Species-specific sensitivities of aflatoxins cannot be fully explained by differences in the metabolism of AFB₁ between animal species. The gut microbiota are critical in inflammatory liver injury, but it remains to reveal the role of gut microbiota in AFB₁-induced liver injury. Here, mice were gavaged with AFB₁ for 28 days. Then, the modulation of gut microbiota, colonic barrier, and liver pyroptosis and inflammation were analyzed. To further verify the direct role of gut microbiota in AFB₁-induced liver injury, mice were treated with antibiotic mixtures (ABXs) to deplete the microbiota, and fecal microbiota transplantation (FMT) was conducted. The treatment of AFB₁ in mice altered gut microbiota composition, such as increasing the relative abundance of Bacteroides, Parabacteroides, and Lactobacillus, inducing colonic barrier dysfunction and promoting liver pyroptosis. In ABX-treated mice, AFB₁ had little effect on the colonic barrier and liver pyroptosis. Notably, after FMT, in which the mice were colonized with gut microbiota from AFB₁-treated mice, colonic barrier dysfunction, and liver pyroptosis and inflammation were obliviously identified. We proposed that the gut microbiota directly participated in AFB₁-induced liver pyroptosis and inflammation. These results provide new insights into the mechanisms of AFB₁ hepatotoxicity and pave a window for new targeted interventions to prevent or reduce AFB₁ hepatotoxicity.