Search Results (88)

Background: Obese women have a significantly higher risk of bearing breast tumors that are resistant to therapies and are associated with poorer prognoses/treatment outcomes. Breast cancer-promoting action of obesity is often attributed to elevated levels of insulin, glucose, inflammatory mediators, and misbalanced estrogen production in adipose tissue under obese conditions. Metabolic endotoxemia, characterized by chronic presence of extremely low levels of bacterial endotoxin (lipopolysaccharide [LPS]) in the circulation, is a less explored obesity-associated factor. Results: Here, utilizing in vitro and in vivo models of breast carcinoma (BC), we report that subclinical levels of LPS typical for metabolic endotoxemia enhance the malignant phenotype of breast cancer cells and accelerate breast tumor progression. Conclusions: Our study, while focusing primarily on the direct effects of metabolic endotoxemia on breast tumor progression, also suggests that metabolic endotoxemia can contribute to obesity–breast cancer link. Thus, our findings add novel mechanistic insights into how obesity-associated metabolic changes, particularly metabolic endotoxemia, modulate the biological and clinical behavior of breast carcinoma. In turn, understanding of the mechanistic aspects underlying the association between obesity and breast cancer could help inform better strategies to reduce BC risk in an increasingly obese population and to suppress the breast cancer-promoting consequences of excess adiposity. Full article

Prion diseases are classically attributed to the accumulation of protease-resistant prion protein (PrP^Sc); however, recent evidence suggests that alternative misfolded prion conformers and systemic inflammatory factors may also contribute to neurodegeneration. This study investigated whether recombinant moPrP^Res, generated by incubating wild-type mouse PrP^C with bacterial lipopolysaccharide (LPS), can induce prion-like disease in FVB/N female mice, whether LPS alone causes neurodegeneration, and how LPS modulates disease progression in mice inoculated with the Rocky Mountain Laboratory (RML) strain of prions. Wild-type female FVB/N mice were randomized into six subcutaneous treatment groups: saline, LPS, moPrP^Res, moPrP^Res + LPS, RML, and RML + LPS. Animals were monitored longitudinally for survival, body weight, and clinical signs. Brain tissues were analyzed histologically and immunohistochemically for vacuolar degeneration, PrP^Sc accumulation, reactive astrogliosis, and amyloid-β plaque deposition. Recombinant moPrP^Res induced a progressive spongiform encephalopathy characterized by widespread vacuolation and astrogliosis, yet with no detectable PrP^Sc by Western blot or immunohistochemistry. LPS alone triggered a distinct neurodegenerative phenotype, including cerebellar amyloid-β plaque accumulation and terminal-stage spongiosis, with approximately 40% mortality by the end of the study. Co-administration of moPrP^Res and LPS resulted in variable regional pathology and intermediate survival (50% at 750 days post-inoculation). Interestingly, RML + LPS co-treatment led to earlier clinical onset and mortality compared to RML alone; however, vacuolation levels were not significantly elevated and, in some brain regions, were reduced. These results demonstrate that chronic endotoxemia and non-infectious misfolded PrP conformers can independently or synergistically induce key neuropathological hallmarks of prion disease, even in the absence of classical PrP^Sc. Targeting inflammatory signaling and toxic prion intermediates may offer novel therapeutic strategies for prion and prion-like disorders. Full article

Endotoxemia often leads to microcirculatory derangement. In six sevoflurane anaesthetized Beagle dogs, we investigated the effects of 1 mg/kg of Escherichia coli lipopolysaccharide endotoxin intravenous and blood pressure (mean arterial pressure of 65 mmHg versus 85 mmHg) on microcirculation assessed on buccal mucosa using side stream dark field microscopy. Dogs were afterwards resuscitated with fluids and noradrenaline. We investigated dose requirements of noradrenaline with or without dexmedetomidine. Microcirculatory parameters, and markers of sepsis (cardiac output, mixed venous oxygen saturation, carbon dioxide gap, and lactate) were analysed before endotoxemia, after endotoxemia, after a 30 mL/kg of Ringer’s acetate fluid bolus, and during noradrenaline +/− dexmedetomidine infusion, after a second fluid bolus, and a second time after vasopressor treatment in a cross-over fashion. Endotoxemia and mean arterial pressure had no statistically significant effect on microcirculation; however, endotoxemia resulted in a decrease in cardiac output. Dexmedetomidine neither improved microcirculation nor reduced noradrenaline requirements. Full article

Background: Type 2 diabetes mellitus (T2DM) represents a major global health burden, with prevalence rates escalating due to rapid urbanization, economic growth, and the obesity epidemic. Despite intensive research, the underlying molecular mechanisms remain incompletely understood, with emerging evidence suggesting multifactorial origins involving genetic, epigenetic, lifestyle, and environmental factors. Methods: This review synthesizes current epidemiological data on T2DM prevalence, risk factors, and demographic patterns from 1990 to 2017, and discusses projected trends through 2030. We examine the role of intestinal barrier dysfunction and gut microbiota dysbiosis in T2DM pathogenesis, highlighting key mechanistic insights. Furthermore, we analyze recent findings on the role of butyrate, a major short-chain fatty acid, in preserving gut integrity and its potential therapeutic effects on metabolic health. Results: Global T2DM prevalence has risen markedly across all age groups, with particularly high rates in Western Europe and Pacific Island nations. Disruption of the intestinal barrier (“leaky gut”) and gut microbiota alterations contribute significantly to systemic inflammation and insulin resistance, which are pivotal features in T2DM development. Butyrate plays a central role in maintaining epithelial barrier function, modulating immune responses, and regulating glucose metabolism. Preclinical studies have demonstrated that sodium butyrate supplementation improves gut integrity, reduces systemic endotoxemia, and ameliorates metabolic parameters. Emerging clinical evidence suggests benefits of sodium butyrate, particularly when combined with prebiotic fibers, in improving glycemic control and reducing inflammatory markers in T2DM patients. Conclusions: Gut barrier integrity and microbiota composition are critical factors in T2DM pathogenesis. Sodium butyrate shows promise as a complementary therapeutic agent in T2DM management, although further large-scale, long-term clinical trials are required to confirm its efficacy and safety. Targeting gut health may represent a novel strategy for the prevention and treatment of T2DM. Full article

Background/Objectives: Childhood obesity is a growing global concern linked to metabolic disorders such as nonalcoholic fatty liver disease (NAFLD). Small intestinal bacterial overgrowth (SIBO) may exacerbate these conditions by promoting systemic inflammation and metabolic dysfunction. This review evaluates the prevalence of SIBO in obese children, its association with inflammatory and metabolic markers, and the efficacy of diagnostic and therapeutic strategies. Methods: A systematic search of PubMed, Scopus, and Web of Science (2010–present) was conducted using Boolean operators: (‘small intestinal bacterial overgrowth’ OR ‘SIBO’) AND ‘prevalence’ AND (‘low-grade inflammatory markers’ OR ‘metabolic status’) AND ‘gut microbiome’ AND ‘dysbiosis’ AND ‘obese children’. Results: The data show that SIBO is frequently observed in obese pediatric populations and is associated with gut dysbiosis, impaired nutrient absorption, and reduced production of short-chain fatty acids. These changes contribute to increased intestinal permeability, endotoxemia, and chronic low-grade inflammation. Several microbial taxa have been proposed as biomarkers and therapeutic targets. Diagnostic inconsistencies persist, but treatments such as probiotics, prebiotics, dietary interventions, and selective antibiotics show potential, pending further validation. Conclusions: Early identification and treatment of SIBO with tailored strategies may help reduce metabolic complications and improve outcomes in children with obesity. Full article

Cirrhotic cardiomyopathy (CCM) is a diagnostic entity defined as cardiac dysfunction (diastolic and/or systolic) in patients with liver cirrhosis, in the absence of overt cardiac disorder. Pathogenically, CCM stems from a combination of systemic and local hepatic factors that, through hemodynamic and neurohormonal changes, affect the balance of cardiac function and lead to its remodeling. Vascular changes in cirrhosis, mostly driven by portal hypertension, splanchnic vasodilatation, and increased cardiac output alongside maladaptively upregulated feedback systems, lead to fluid accumulation, venostasis, and cardiac dysfunction. Autocrine and endocrine proinflammatory cytokines (TNF-alpha, IL-6), as well as systemic endotoxemia stemming from impaired intestinal permeability, contribute to myocardial remodeling and fibrosis, which further compromise the contractility and relaxation of the heart. Additionally, relative adrenal insufficiency is often present in cirrhosis, further potentiating cardiac dysfunction, ultimately leading to the development of CCM. Considering its subclinical course, CCM diagnosis remains challenging. It relies mostly on stress echocardiography or advanced imaging techniques such as speckle-tracking echocardiography. Currently, there is no specific treatment for CCM, as it vastly overlaps with the treatment of heart failure. Diuretics play a central role. The role of non-selective beta-blockers in treating portal hypertension is established; however, their role in CCM remains somewhat controversial as their effect on prognosis is unclear. However, our group still advocates them as essential tools in optimizing the neurohumoral pathologic axis that perpetuates CCM. Other targeted therapies with direct anti-inflammatory and antioxidative effects still lack sufficient evidence for wide approval. This is not only a review but also a comprehensive distillation of the insights from practicing clinical hepatologists and other specialties engaged in advanced approaches to treating liver disease and its sequelae. Full article

The gut–kidney axis represents the complex interactions between the gut microbiota and kidney, which significantly impact the progression of chronic kidney disease (CKD) and overall patient health. In CKD patients, imbalances in the gut microbiota promote the production of uremic toxins, such as indoxyl sulfate and p-cresyl sulfate, which impair renal function and contribute to systemic inflammation. Mechanisms like endotoxemia, immune activation and oxidative stress worsen renal damage by activating pro-inflammatory and oxidative pathways. Insights into these mechanisms highlight the impact of gut-derived metabolites, bacterial translocation, and immune response changes on kidney health, suggesting new potential approaches for CKD treatment. Clinical applications, such as dietary interventions, prebiotics, probiotics and fecal microbiota transplantation, are promising in adjusting the gut microbiota to alleviate CKD symptoms and slow disease progression. Current research highlights the clinical relevance of the gut–kidney axis, but further study is essential to clarify these mechanisms’ diagnostic biomarkers and optimize therapeutic interventions. This review emphasizes the importance of an integrated approach to CKD management, focusing on the gut microbiota as a therapeutic target to limit kidney injury. Full article

Systemic inflammatory response syndrome (SIRS) in donkeys is observed to be secondary to colic, diarrhea or pleuropneumonia, among other disorders. Horses with SIRS develop secondary disturbances such as hyperlipemia, laminitis, disseminated intravascular coagulopathy, and hemodynamic and cardiac derangements, which impair their prognosis and increase the mortality rate. In donkeys, no information is available on the effect of experimentally induced endotoxemia in the cardiovascular system. Acute experimental endotoxemia was induced by lipopolysaccharide (LPS) infusion in six healthy adult non-pregnant jennies. Physical signs, arterial (systolic, diastolic and mean) and central venous pressure were monitored during 360 min. Cardiac troponin I (cTnI) concentrations were measured in blood samples, and echocardiography was performed. LPS infusion caused an increase in cTnI, hypotension and diminution of central venous pressure, cardiac dysfunction, with a decrease in stroke volume (SV), cardiac output (CO) and cardiac index, and impairment of ultrasonographic ventricular function parameters. Intravenous meloxicam administration prevented the cTnI increase, hypotension, diminution of SV and CO, and changes in ultrasonographic parameters related to ventricular dysfunction. Thus, meloxicam could be proposed as an effective therapeutical option to control the hemodynamic and cardiac derangements observed in donkeys with SIRS. Full article

Preeclampsia (PE) is a serious complication of pregnancy linked to endothelial dysfunction and an imbalance in the gut microbiota. While Akkermansia muciniphila (AKK) has shown promise in alleviating PE symptoms, the use of live bacteria raises safety concerns. This study explored the potential of pasteurized A. muciniphila (pAKK) as a safer alternative for treating PE, focusing on its effects on endothelial function and metabolic regulation. A PE mouse model was induced via the nitric oxide synthase inhibitor L-NAME, followed by treatment with either pAKK or live AKK. Fecal metabolomic profiling was performed via liquid chromatography–tandem mass spectrometry (LC-MS/MS), and in vivo and in vitro experiments were used to assess the effects of pAKK on endothelial function and metabolic pathways. pAKK exhibited therapeutic effects comparable to those of live AKK in improving L-NAME-induced PE-like phenotypes in mice, including enhanced gut barrier function and reduced endotoxemia. pAKK also promoted placental angiogenesis by restoring endothelial nitric oxide synthase (eNOS) activity and nitric oxide (NO) production. The in vitro experiments further confirmed that pAKK alleviated L-NAME-induced NO reduction and endothelial dysfunction in human umbilical vein endothelial cells (HUVECs). Metabolomic analysis revealed that both pAKK and live AKK reversed metabolic disturbances in PE by modulating key metabolites and pathways related to unsaturated fatty acid biosynthesis, folate, and linoleic acid metabolism. As a postbiotic, pAKK may support existing treatments for preeclampsia by improving gut barrier function, restoring endothelial function, and regulating metabolic dysregulation, offering a safer alternative to live bacteria. These findings highlight the potential clinical value of pAKK as an adjunctive therapy in managing PE. Full article

Type 2 diabetes (T2D) is a chronic metabolic disorder with a heterogeneous etiology encompassing societal and behavioral risk factors in addition to genetic and environmental susceptibility. The cardiovascular consequences of diabetes account for more than two-thirds of mortality among people with T2D. Not only does T2D shorten life expectancy, but it also lowers quality of life and is associated with extremely high health expenditures since diabetic complications raise both direct and indirect healthcare costs. An increasing body of research indicates a connection between T2D and gut microbial traits, as numerous alterations in the intestinal microorganisms have been noted in pre-diabetic and diabetic individuals. These include pro-inflammatory bacterial patterns, increased intestinal permeability, endotoxemia, and hyperglycemia-favoring conditions, such as the alteration of glucagon-like peptide-1 (GLP-1) secretion. Restoring microbial homeostasis can be very beneficial for preventing and co-treating T2D and improving antidiabetic therapy outcomes. This review summarizes the characteristics of a “diabetic” microbiota and the metabolites produced by microbial species that can worsen or ameliorate T2D risk and progression, suggesting gut microbiota-targeted strategies to restore eubiosis and regulate blood glucose. Nutritional supplementation, diet, and physical exercise are known to play important roles in T2D, and here their effects on the gut microbiota are discussed, suggesting non-pharmacological approaches that can greatly help in diabetes management and highlighting the importance of tailoring treatments to individual needs. Full article

The present study involved seven horses in a randomized crossover clinical trial to evaluate the effect of lidocaine on horses with induced endotoxemia. Horses received intravenous lidocaine (1.5 mg/kg bolus, followed by 0.05 mg/kg bwt/min) or placebo (0.9% sodium chloride at the same manner) one hour before LPS administration (0.03 μg/kg, IV infusion over 30 min). We monitored clinic and hematologic parameters, abdominal auscultation, ultrasound, and pain over time. No relevant clinical differences existed between treatments regarding peristalsis, abdominal pain, or any other parameters before and after endotoxemia induction. These findings do not support the clinical use of lidocaine to mitigate abdominal pain and intestinal hypomotility promoted by endotoxemia in horses. Full article

Sepsis is a complex disorder caused by a dysregulated host response to infection, with high levels of morbidity and mortality. Treatment aimed to modulate immune response and maintain vascular function is still one of the major clinical challenges. This study was designed to test the effect of the small molecule 1-Piperidine Propionic Acid (1-PPA) as molecular targeted agent to block protease-activated receptor 2 (PAR2), one of the major modulators of inflammatory response in LPS-induced experimental endotoxemia. In the THP-1 cell line, LPS-induced cytokine expression was inhibited by 1-PPA in a dose-dependent manner. In LPS-injected mice, treatment with 1-PPA was effective in reducing mortality and sepsis-related symptoms and improved cardiac function parameters. After 6 h from LPS injection, a significant decrease in IL-6, IL-1β, and IL-10 was observed in the lung tissue of 1-PPA-treated mice, compared to controls. In these mice, a significant decrease in vasoactive molecules, especially kininogen-1, was also observed, mainly in the liver. Histopathological analysis confirmed typical features of sepsis in different organs and these findings were markedly reduced in mice treated with 1-PPA. These data demonstrate the effectiveness of 1-PPA in protecting the whole organism from sepsis-induced damage. Full article

Low-grade endotoxemia by lipopolysaccharide (LPS) has been detected in COVID-19 and could favor thrombosis via eliciting a pro-inflammatory and pro-coagulant state. The aim of this study was to analyze the mechanism accounting for low-grade endotoxemia and its relationship with oxidative stress and clotting activation thrombosis in COVID-19. We measured serum levels of sNOX2-dp, zonulin, LPS, D-dimer, and albumin in 175 patients with COVID-19, classified as having or not acute respiratory distress syndrome (ARDS), and 50 healthy subjects. Baseline levels of sNOX2-dp, LPS, zonulin, D-dimer, albumin, and hs-CRP were significantly higher in COVID-19 compared to controls. In COVID-19 patients with ARDS, sNOX2-dp, LPS, zonulin, D-dimer, and hs-CRP were significantly higher compared to COVID-19 patients without ARDS. Conversely, concentration of albumin was lower in patients with ARDS compared with those without ARDS and inversely associated with LPS. In the COVID-19 cohort, the number of patients with ARDS progressively increased according to sNOX2-dp and LPS quartiles; a significant correlation between LPS and sNOX2-dp and LPS and D-dimer was detected in COVID-19. In a multivariable logistic regression model, LPS/albumin levels and D-dimer predicted thrombotic events. In COVID-19 patients, LPS is significantly associated with a hypercoagulation state and disease severity. In vitro, LPS can increase endothelial oxidative stress and coagulation biomarkers that were reduced by the treatment with albumin. In conclusion, impaired gut barrier permeability, increased NOX2 activation, and low serum albumin may account for low-grade endotoxemia and may be implicated in thrombotic events in COVID-19. Full article

Aging, an independent risk factor for cardiometabolic diseases, refers to a progressive deterioration in physiological function, characterized by 12 established hallmarks. Vascular aging is driven by endothelial dysfunction, telomere dysfunction, oxidative stress, and vascular inflammation. This study investigated whether aged gut microbiome promotes vascular aging and metabolic impairment. Fecal microbiome transfer (FMT) was conducted from aged (>75 weeks old) to young C57BL/6 mice (8 weeks old) for 6 weeks. Wire myography was used to evaluate endothelial function in aortas and mesenteric arteries. ROS levels were measured by dihydroethidium (DHE) staining and lucigenin-enhanced chemiluminescence. Vascular and intestinal telomere function, in terms of relative telomere length, telomerase reverse transcriptase expression and telomerase activity, were measured. Systemic inflammation, endotoxemia and intestinal integrity of mice were assessed. Gut microbiome profiles were studied by 16S rRNA sequencing. Some middle-aged mice (40–42 weeks old) were subjected to chronic metformin treatment and exercise training for 4 weeks to evaluate their anti-aging benefits. Six-week FMT impaired glucose homeostasis and caused vascular dysfunction in aortas and mesenteric arteries in young mice. FMT triggered vascular inflammation and oxidative stress, along with declined telomerase activity and shorter telomere length in aortas. Additionally, FMT impaired intestinal integrity, and triggered AMPK inactivation and telomere dysfunction in intestines, potentially attributed to the altered gut microbial profiles. Metformin treatment and moderate exercise improved integrity, AMPK activation and telomere function in mouse intestines. Our data highlight aged microbiome as a mechanism that accelerates intestinal and vascular aging, suggesting the gut-vascular connection as a potential intervention target against cardiovascular aging and complications. Full article

Metabolic endotoxemia (ME) is associated with bacterial lipopolysaccharide (LPS, endotoxin) and increased levels of saturated fatty acids (SFAs) in the bloodstream, causing systemic inflammation. ME usually accompanies obesity and a diet rich in fats, especially SFAs. Numerous studies confirm the effect of ME-related endotoxin on microglial activation. Our study aimed to assess lipid metabolism and immune response in microglia pre-stimulated with TNFα (Tumor Necrosis Factor α) and then with endotoxin and palmitic acid (PA). Using ELISA, we determined cytokines IL-1β, IL-10, IL-13 (interleukin-1β, -10, -13, and TGFβ (Transforming Growth Factor β) in the culture medium from microglial cells stimulated for 24 h with TNFα and then treated with LPS (10 ng/mL) and PA (200 µM) for 24 h. HMC3 (Human Microglial Cells clone 3) cells produced negligible amounts of IL-1β, IL-10, and IL-13 after stimulation but secreted moderate levels of TGFβ. Changes in lipid metabolism accompanied changes in TREM2 (Triggering Receptor Expressed on Myeloid Cells 2) expression. HMC3 stimulation with endotoxin increased TREM2 expression, while PA treatment decreased it. Endotoxin increased ceramide levels, while PA increased triglyceride levels. These results indicated that pre-stimulation of microglia with TNFα significantly affects its interactions with LPS and PA and modulates lipid metabolism, which may lead to microglial activation silencing and neurodegeneration. Full article