Stool Short-Chain Fatty Acids in Critically Ill Patients with Sepsis.

Objective: To determine the concentration of stool short-chain fatty acids (SCFAs) in critically ill patients with sepsis and to compare the results between the critically ill patient and the control group.Methods: This descriptive, multicenter, observational study was conducted in five health institutions. Over a 6-month study period, critically ill patients with sepsis who were admitted to the intensive care unit (ICU) and met the inclusion criteria were enrolled, and a control, paired by age and sex, was recruited for each patient. A spontaneous stool sample was collected from each participant and a gas chromatograph coupled to a mass spectrometer (Agilent 7890/MSD 5975 C) was used to measure the concentrations SCFAs.Results: The final sample included 44 patients and 45 controls. There were no differences in the age and sex distributions between the groups (p > 0.05). According to body mass index (BMI), undernutrition was more prevalent among critically ill patients, and BMI in control subjects was most frequently classified as overweight (p = 0.024). Propionic acid, acetic acid, butyric acid, and isobutyric acid concentrations were significantly lower in the critically ill patient group than in the control group (p = 0.000). No association with outcome variables (complications, ICU stay, and discharge condition) was found in the patients, and patients diagnosed with infection on ICU admission showed significant decreases in butyric and isobutyric acid concentrations with respect to other diagnostic criteria (p < 0.05).Conclusions: The results confirm significantly lower concentrations of stool SCFAs in critically ill patients with sepsis than in control subjects. Due to its role in intestinal integrity, barrier function, and anti-inflammatory effect, maintaining the concentration of SCFAs may be important in the ICU care protocols of the critical patient.

Gut microbiota profiles in critically ill patients, potential biomarkers and risk variables for sepsis.

Critically ill patients are physiologically unstable and recent studies indicate that the intestinal microbiota could be involved in the health decline of such patients during ICU stays. This study aims to assess the intestinal microbiota in critically ill patients with and without sepsis and to determine its impact on outcome variables, such as medical complications, ICU stay time, and mortality. A multi-center study was conducted with a total of 250 peri-rectal swabs obtained from 155 patients upon admission and during ICU stays. Intestinal microbiota was assessed by sequencing the V3-V4 hypervariable regions of the 16S rRNA gene. Linear mixed models were used to integrate microbiota data with more than 40 clinical and demographic variables to detect covariates and minimize the effect of confounding factors. We found that the microbiota of ICU patients with sepsis has an increased abundance of microbes tightly associated with inflammation, such as Parabacteroides, Fusobacterium and Bilophila species. Female sex and aging would represent an increased risk for sepsis possibly because of some of their microbiota features. We also evidenced a remarkable loss of microbial diversity, during the ICU stay. Concomitantly, we detected that the abundance of pathogenic species, such as Enterococcus spp., was differentially increased in sepsis patients who died, indicating these species as potential biomarkers for monitoring during ICU stay. We concluded that particular intestinal microbiota signatures could predict sepsis development in ICU patients. We propose potential biomarkers for evaluation in the clinical management of ICU patients.

Microbiota intestinal y ácidos grasos de cadena corta en pacientes críticos / Gut Microbiota and Short-Chain Fatty Acids in Critically Ill Patients

Resumen Antecedentes: diversos estudios han mostrado cambios en la microbiota intestinal (MI) y los ácidos grasos de cadena corta (AGCC) en pacientes críticos con síndrome de respuesta inflamatoria sistémica (SRIS). Objetivo: revisar la evidencia sobre el papel de la MI y los AGCC en pacientes críticos y su modulación con prebióticos, probióticos y simbióticos. Materiales y métodos: búsqueda de artículos en bases de datos bibliográficas Pubmed, Science Direct, Ovid, Medline y Scopus, utilizando como descriptores microbiota, paciente crítico, unidad de cuidados intensivos, síndrome de respuesta inflamatoria sistémica, ácidos grasos de cadena corta, probióticos, prebióticos y simbióticos. Resultados: la MI en pacientes críticos está disminuida tanto en número de bacterias como en diversidad, lo cual puede resultar en una desregulación de la respuesta inmune sistémica ante la invasión de microorganismos patógenos. Los cambios en los AGCC en pacientes críticos se atribuyen a una disminución de bacterias anaerobias obligadas y sustratos de fermentación necesarios para su producción. La modulación de la MI con probióticos, prebióticos y simbióticos sugiere mejoría en la función intestinal. Conclusiones: la MI y los AGCC en pacientes críticos se encuentran alterados, de ahí que mantener el equilibrio en el entorno intestinal probablemente desempeñe una función clave para disminuir complicaciones y mejorar su pronóstico.

Abstract Background: Different studies have shown changes in gut microbiota and short-chain fatty acids in critically ill patients with Systemic Inflammatory Response Syndrome (SIRS). Aim: To review the evidence about the role of gut microbiota and SCFAs in critically patients and its modulation with prebiotics, probiotics and symbiotic. Materials and Methods: A search of the literature in Pubmed, Science Direct, Ovid, Medline and Scopus databases was conducted. The terms used were microbiota, critically ill, intensive care unit, systemic inflammatory response syndrome, short-chain fatty acids, prebiotics, probiotics and symbiotic. Results: The intestinal microbiota in critically ill patients is reduced in number and diversity, which can lead to dysregulation of the systemic immune response to the pathogenic invasion. Changes in SCFAs in critically ill patients are attributed to a decrease of obligate anaerobic bacteria and the fermentation substrates required for its production. The gut microbiota modulation with prebiotics, probiotics and symbiotic suggest improvement in bowel function. Conclusions: Gut microbiota and SCFAs are altered in critically ill patients; therefore, maintaining the intestinal environment is key for reducing complications and improving prognosis.

Coffee Consumption Increases the Antioxidant Capacity of Plasma and Has No Effect on the Lipid Profile or Vascular Function in Healthy Adults in a Randomized Controlled Trial.

BACKGROUND: Coffee, a source of antioxidants, has controversial effects on cardiovascular health. OBJECTIVE: We evaluated the bioavailability of chlorogenic acids (CGAs) in 2 coffees and the effects of their consumption on the plasma antioxidant capacity (AC), the serum lipid profile, and the vascular function in healthy adults. METHODS: Thirty-eight men and 37 women with a mean ± SD age of 38.5 ± 9 y and body mass index of 24.1 ± 2.6 kg/m(2) were randomly assigned to 3 groups: a control group that did not consume coffee or a placebo and 2 groups that consumed 400 mL coffee/d for 8 wk containing a medium (MCCGA; 420 mg) or high (HCCGA; 780 mg) CGA content. Both were low in diterpenes (0.83 mg/d) and caffeine (193 mg/d). Plasma caffeic and ferulic acid concentrations were measured by GC, and the plasma AC was evaluated with use of the ferric-reducing antioxidant power method. The serum lipid profile, nitric oxide (NO) plasma metabolites, vascular endothelial function (flow-mediated dilation; FMD), and blood pressure (BP) were evaluated. RESULTS: After coffee consumption (1 h and 8 wk), caffeic and ferulic acid concentrations increased in the coffee-drinking groups, although the values of the 2 groups were significantly different (P < 0.001); caffeic and ferulic acid concentrations were undetectable in the control group. At 1 h after consumption, the plasma AC in the control group was significantly lower than the baseline value (-2%) and significantly increased in the MCCGA (6%) and HCCGA (5%) groups (P < 0.05). After 8 wk, no significant differences in the lipid, FMD, BP, or NO plasma metabolite values were observed between the groups. CONCLUSIONS: Both coffees, which contained CGAs and were low in diterpenes and caffeine, provided bioavailable CGAs and had a positive acute effect on the plasma AC in healthy adults and no effect on blood lipids or vascular function. The group that did not drink coffee showed no improvement in serum lipid profile, FMD, BP, or NO plasma metabolites. This trial was registered at registroclinico.sld.cu as RPCEC00000168.