Short-chain Fatty Acids In Patients Research Articles

Expression and clinical significance of short-chain fatty acids in patients with intrahepatic cholestasis of pregnancy.

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver condition that typically arises in the middle and late stages of pregnancy. Short-chain fatty acids (SCFAs), prominent metabolites of the gut microbiota, have significant connections with various pregnancy complications, and some SCFAs hold potential for treating such complications. However, the metabolic profile of SCFAs in patients with ICP remains unclear. To investigate the metabolic profiles and differences in SCFAs present in the maternal and cord blood of patients with ICP and determine the clinical significance of these findings. Maternal serum and cord blood samples were collected from both patients with ICP (ICP group) and normal pregnant women (NP group). Targeted metabolomics was used to assess the SCFA levels in these samples. Significant differences in maternal SCFAs were observed between the ICP and NP groups. Most SCFAs exhibited a consistent declining trend in cord blood samples from the ICP group, mirroring the pattern seen in maternal serum. Correlation analysis revealed a positive correlation between maternal serum SCFAs and cord blood SCFAs [r (Pearson) = 0.88, P = 7.93e-95]. In both maternal serum and cord blood, acetic and caproic acids were identified as key metabolites contributing to the differences in SCFAs between the two groups (variable importance for the projection > 1). Receiver operating characteristic analysis demonstrated that multiple SCFAs in maternal blood have excellent diagnostic capabilities for ICP, with caproic acid exhibiting the highest diagnostic efficacy (area under the curve = 0.97). Compared with the NP group, significant alterations were observed in the SCFAs of maternal serum and cord blood in the ICP group, although they displayed distinct patterns of change. Furthermore, the SCFA levels in maternal serum and cord blood were significantly positively correlated. Notably, certain maternal serum SCFAs, specifically caproic and acetic acids, demonstrated excellent diagnostic efficiency for ICP.

Systematic review of the association between short chain fatty acids and allergic diseases.

We performed a systematic review to investigate the current evidence on the association between allergic diseases and short chain fatty acids (SCFAs), which are microbially produced and suggested as one mechanism on how gut microbiome affects the risk of allergic diseases. Medline, Embase and Web of Science were searched from data inception until September 2022. We identified 37 papers, of which 17 investigated prenatal or early childhood SCFAs and the development of allergic diseases in childhood, and 20 assessed SCFAs in patients with pre-existing allergic diseases. Study design, study populations, outcome definition, analysis method and reporting of the results varied between papers. Overall, there was some evidence showing that the three main SCFAs (acetate, propionate and butyrate) in the first few years of life had a protective effect against allergic diseases, especially for atopic dermatitis, wheeze or asthma and IgE-mediated food allergy in childhood. The association between each SCFA and allergic disease appeared to be different by disease and the age of assessment. Further research that can determine the potentially timing specific effect of each SCFA will be useful to investigate how SCFAs can be used in treatment or in prevention against allergic diseases.

Targeted metabolomics reveals plasma short-chain fatty acids are associated with metabolic dysfunction-associated steatotic liver disease

BackgroundAlterations in the production of short-chain fatty acids (SCFAs) may reflect disturbances in the gut microbiota and have been linked to metabolic dysfunction-associated steatotic liver disease (MASLD). We assessed plasma SCFAs in patients with MASLD and healthy controls.MethodsFasting venous blood samples were collected and eight SCFAs were measured using gas chromatography-tandem mass spectrometry (GC-MS/MS). Relative between-group differences in circulating SCFA concentrations were estimated by linear regression, and the relation between SCFA concentrations, MASLD, and fibrosis severity was investigated using logistic regression.ResultsThe study includes 100 patients with MASLD (51% with mild/no fibrosis and 49% with significant fibrosis) and 50 healthy controls. Compared with healthy controls, MASLD patients had higher plasma concentrations of propionate (21.8%, 95% CI 3.33 to 43.6, p = 0.02), formate (21.9%, 95% CI 6.99 to 38.9, p = 0.003), valerate (35.7%, 95% CI 4.53 to 76.2, p = 0.02), and α-methylbutyrate (16.2%, 95% CI 3.66 to 30.3, p = 0.01) but lower plasma acetate concentrations (− 30.0%, 95% CI − 40.4 to − 17.9, p < 0.001). Among patients with MASLD, significant fibrosis was positively associated with propionate (p = 0.02), butyrate (p = 0.03), valerate (p = 0.03), and α-methylbutyrate (p = 0.02). Six of eight SCFAs were significantly increased in F4 fibrosis.ConclusionsIn the present study, SCFAs were associated with MASLD and fibrosis severity, but further research is needed to elucidate the potential mechanisms underlying our observations and to assess the possible benefit of therapies modulating gut microbiota.

[Changes in the synthesis of short-chain fatty acids under the influence of various factors in healthy people and patients with type 2 diabetes mellitus].

Short-chain fatty acids (SCFAs) are an important link in the maintenance and normalization of some important body functions. Recently, the metabolic component of the SCFAs effects has also been actively studied; the effect on body weight, insulin resistance and glycemia is of particular interest in the context of the prevention and treatment of carbohydrate metabolism disorders. In this regard, it is relevant to study the characteristics of SCFAs' production in patients with impaired carbohydrate metabolism, mainly with type 2 diabetes mellitus (T2DM). The purpose of the research was to study the modern data on the synthesis peculiarities of SCFAs in healthy people and patients with impaired carbohydrate metabolism. Material and methods. The data of domestic and foreign literature presented in PubMed, Google Scholar, ResearchGate, Elsevier, eLibrary, CyberLeninka databases, published mainly over the past 10 years, have been analyzed. Results. According to the concept of the philometabolic nucleus, bacteria of certain species, which are of the greatest importance compared to the rest, are responsible for the synthesis of specific SCFAs. The gut microbiota (GM) has the property of plasticity - the ability to change its composition under the influence of various factors. Most studies describe the effect of GM and its metabolites on the carbohydrate metabolism, but an equally important aspect of this process is the effect of carbohydrate metabolism disorders on GM and its functional activity. In case of disorders of carbohydrate metabolism, some altered components of homeostasis negatively affect GM and its production of SCFAs. As a result, the total amount and variety of SCFAs decrease, which exacerbate the imbalance in relation to carbohydrate metabolism. There is evidence that in patients with T2DM, the concentration of butyrate, which has a positive effect on insulin resistance, body weight, fasting glycemia and postprandial glycemia, decreases. The concentration of propionate and acetate, which didn't show such a pronounced positive effect in studies on carbohydrate metabolism, on the contrary, increases. Conclusion. The production of SCFAs by GM representatives depends on many factors, such as nutrition, physical activity, medication intake and the presence of chronic diseases. Numerous studies have confirmed the difference in the characteristics of the production of SCFAs in patients with T2DM and healthy people. The study of the peculiarities of GM metabolism in patients with T2DM is a tool in understanding the basics of therapy and lifestyle correction in both patients with T2DM and healthy people in order to prevent disorders of carbohydrate metabolism.

Effects of acupuncture on gut microbiota and short-chain fatty acids in patients with functional constipation: a randomized placebo-controlled trial.

Objective: To comprehensively evaluate the effect of acupuncture on gut microbiota, identify specific microbes closely related to the clinical efficacy of acupuncture, and explored the role of short-chain fatty acids (SCFAs). Methods: A randomized placebo-controlled trial was conducted with 80 FC patients and 28 healthy controls (HCs). FC patients randomly received 16 acupuncture (n = 40) or sham acupuncture (n = 40) sessions over 4weeks; HCs received no treatment. The change in the proportion of patients with mean weekly complete spontaneous bowel movements (CSBMs) was considered as the primary outcome measure. Moreover, the composition and the predictive metabolic function of the gut microbiota from feceal samples were analyzed by 16S rRNA gene sequencing, while feceal SCFAs were identified via gas chromatography-mass spectrometry (GC-MS). Results: Compared to sham acupuncture, acupuncture significantly increased the proportion of CSBM responders, and improved spontaneous bowel movements (SBMs), straining, stool consistency, and quality of life. Moreover, Sequencing of 16S rRNA genes revealed that acupuncture improved β-diversity and restored the composition of gut microbiota. Specifically, the abundance of beneficial bacteria such as g_Lactobacillus increased while that of pathogenic bacteria such as g_Pseudomonas decreased after acupuncture, which were significantly correlated with alleviated symptoms. Moreover, ten microbes including g_Coprobacter, g_Lactobacillus, and g_Eubacterium_coprostanoligenes_group might be considered acupuncture-specific microbes, and formed a stable interaction network. Additionally, GC-MS analysis indicated that acupuncture increased the content of butyrate acid in the gut, which was positively correlated with an increase in defecation frequency and a decrease in acupuncture-related pathogens. Finally, acupuncture specific-microbes including g_Coprobacter, g_Lactobacillus, g_Pseudomonas, g_Eubacterium_coprostanoligenes_group, g_Erysipelotrichaceae_UCG.003, g_Prevotellaceae_UCG.001, and g_Rolstonia could accurately predict the clinical efficacy of acupuncture (AUC = 0.918). Conclusion: Acupuncture could effectively improve clinical symptoms in FC patients, and was associated with gut microbiota reshaping and increased butyrate acid levels. Moreover, key microbial genera such as g_Coprobacter and g_Lactobacillus was predictive of acupuncture efficacy in treating FC. Future studies are required to validate the causal relationship between key microbial genera and acupuncture clinical efficacy, and should explore further metabolic pathways for designing personalized treatment strategies. Clinical Trial Registration: http://www.chictr.org.cn, Identifier: ChiCTR2100048831.

Altered levels of fecal short-chain fatty acids are associated with subclinical inflammation and worse cognitive performance in patients with schizophrenia

Schizophrenia is a multi-systemic disorder that is associated with lipid profile disturbances, altered glucose homeostasis and subclinical inflammation. It has been proposed that dysfunction of the gut-brain axis might underlie these alterations. Short-chain fatty acids (SCFAs) are considered to play a pivotal role in the gut-brain axis. In this study, we aimed to compare fecal levels of SCFAs in patients with schizophrenia and healthy controls (HCs), taking into consideration their relationship with common peripheral blood alterations observed in schizophrenia. The study included 100 stable outpatients with schizophrenia and 55 HCs. The levels of SCFAs (acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, and lactic acid) in fecal samples were measured. Also, lipid profile together with the levels of C-reactive protein, glucose and insulin were determined. The levels of isovaleric acid were significantly higher in patients with schizophrenia after co-varying for age, sex, and the adherence to the Mediterranean diet. Moreover, there were significant positive correlations of the levels of valeric acid, isovaleric acid and CRP in patients with schizophrenia. In this group of participants, higher levels of isovaleric acid were associated with significantly lower scores of delayed memory after adjustment for potential covariates and interactions with CRP levels. Our results indicate that individuals with schizophrenia show altered levels of isovaleric acid that might be associated with impairments of delayed memory. The association with cognitive impairments might be independent of interactions with immune-inflammatory processes. Longitudinal and experimental studies are needed to test causal mechanisms of observed correlations.

The profile of key gut microbiota members and short-chain fatty acids in patients with sepsis

Sepsis is a complex clinical disorder with heterogeneous etiological factors. Given its high mortality rate, it is considered a global health issue. Recently, the link between gut microbiota and their metabolites, especially short-chain fatty acids, in the pathophysiology of sepsis has been reported. However, there are few findings to confirm this relationship. This study aimed to evaluate some key gut microbiota members, pathogenic bacteria, and short-chain fatty acids in non-ICU patients with sepsis caused by bacteremia compared to a control group. In this case-control study, 45 stool samples from patients with sepsis and 15 healthy persons were collected from October 2021 to August 2022 in Tabriz, Iran. The position of some gut microbiota members and the main short-chain fatty acids concentration were assessed in the two groups by the Q-PCR and the high-performance liquid chromatography system. Faecalibacterium prausnitzii and Bifidobacterium sp. As bacterial with protective features in non-ICU patients with sepsis decreased significantly. Moreover, the concentrations of acetic acid and propionic acid significantly decreased in this group compared to the healthy volunteers. In contrast, the pathogenic bacteria members such as Enterobacteriaceae and Bacteroides sp. Increased significantly in the patients compared to the healthy individuals. The concentration of butyric acid decreased in the patients, but this change was not significant in the two groups. Protective and immune functions of F. prausnitzii and Bifidobacterium sp., as well as acetate and propionate, are evident. In this investigation, this profile was significantly reduced in non-ICU patients with sepsis compared to the control group.

Features of gut microbiota and short-chain fatty acids in patients with first-episode depression and their relationship with the clinical symptoms.

To compare the differences in gut microbiota and short-chain fatty acids (SCFAs; metabolites of gut microbiota) in the serum of patients with first-episode depression and the healthy population and to analyze the relationship between gut microbiota and metabolite SCFAs and the clinical symptoms of major depressive disorder (MDD). A total of 45 patients with first-episode depression and 22 healthy volunteers were chosen to complete relevant scale evaluations, and feces samples and venous blood samples were collected. The 16S RNA method was used to analyze the intestinal microflora and the characteristics of serum SCFAs detection by ELISA kit, as well as the intestinal flora, SCFAs content and their correlation with MDD clinical indicators. The abundance of Akkermansia, Megamonas, Prevotellaceae NK3B31 group, and butyrate-producing bacteria, Lachnospira, Subdoligranulum, Blautia, and Dialister, and acetate-producing bacteria, Streptococcus, in the gut microbiota of the MDD group was lower than that in the control (C) group. The abundance of Parasutterella in the MDD group was higher than that in the C group. Dialister negatively correlated with all measured clinical symptoms (r < 0, P < 0.05). The serum SCFA content in the MDD group was higher than that in the C group, and the content positively correlated with the Hamilton anxiety scale scores (r = 0.584, P < 0.05). The results demonstrated that the MDD group differed from the C group in terms of gut microbiota and SCFAs in the serum and that the change in certain intestinal bacteria might participate in the pathogenic mechanism of MDD.

Association of plasma propionate concentration with coronary artery disease in a large cross-sectional study.

Microbiome has been linked to the pathogenesis of coronary artery disease (CAD) but data providing direct evidence for an association of short-chain fatty acids (SCFA) with CAD are lacking. This study aimed to evaluate the role of propionate, the most important SCFA in patients with CAD. We performed a cross-sectional study enrolling patients admitted for invasive coronary angiography in two university hospitals in Germany. Patients with known or suspected CAD and risk factors for cardiovascular disease were prospectively recruited. Blood sampling was performed after overnight fasting and before invasive procedures. Measurement of propionate was performed by liquid chromatography. The study included 1,253 patients (median [IQR], 67 [58-76] years; 799 men [64%]). A total of 739 had invasively confirmed CAD with at least one coronary artery stenosis ≥50% and 514 had exclusion of CAD. CAD patients had significant lower levels of propionate (median 5.75 μM, IQR, 4.1-7.6) compared to the non-CAD groups 6.53 μM (4.6-8.6, p < 0.001). Multivariate linear regression analysis revealed an odds ratio of 0.94 (CI 0.90-0.98, p = 0.002) for propionate as predictor of CAD. The odds ratio was further decreased to 0.45 (CI 0.31-0.65, p < 0.001) when comparing patients in the lowest quartile of propionate with those with higher levels of propionate. The study provides large-scale in vivo data for the association of propionate to manifest coronary artery disease, independent of other traditional cardiovascular risk factors.

Short-chain fatty acids in patients with schizophrenia and ultra-high risk population.

Individuals who experience the prodromal phase of schizophrenia (SCZ), a common and complex psychiatric disorder, are referred to as ultra-high-risk (UHR) individuals. Short-chain fatty acid (SCFA) is imperative in the microbiota-gut-brain axis and brain function. Accumulating amount of evidence shows the connections between psychiatric disorders and SCFAs. This study aims to explore the underlying roles SCFAs play in SCZ by investigating the association of alterations in SCFAs concentrations with common cognitive functions in both the SCZ and UHR populations. The study recruited 59 SCZ patients (including 15 participants converted from the UHR group), 51 UHR participants, and 40 healthy controls (HC) within a complete follow-up of 2 years. Results of cognitive functions, which were assessed by utilizing HVLT-R and TMT, and serum concentrations of SCFAs were obtained for all participants and for UHR individuals at the time of their conversion to SCZ. Fifteen UHR participants converted to SCZ within a 2-year follow-up. Valeric acid concentration levels were lower in both the baseline of UHR individuals whom later converted to SCZ (p = 0.046) and SCZ patients (p = 0.036) than the HC group. Additionally, there were lower concentrations of caproic acid in the baseline of UHR individuals whom later transitioned to SCZ (p = 0.019) and the UHR group (p = 0.016) than the HC group. Furthermore, the caproic acid levels in the UHR group are significantly positively correlated with immediate memory (r = 0.355, p = 0.011) and negatively correlated with TMT-B (r = -0.366, p = 0.009). Significant differences in levels of acetic acid, butyric acid and isovaleric acid were absent among the three groups and in UHR individuals before and after transition to SCZ. Our study suggests that alterations in concentrations of SCFAs may be associated with the pathogenesis and the cognitive impairment of schizophrenia. Further researches are warranted to explore this association. The clinical implications of our findings were discussed.

Intestinal disorders after acute diarrhea in young children and their coprological predictors

Background. After acute diarrhea in young children, intestinal disturbances and even chronic functional intestinal diseases may occur. To date, no pathogenetically based criteria have been found that would indicate the probability of chronic intestinal disorders, just as the mechanisms of their occurrence after acute diarrhea have not been fully elucidated. The objective: to evaluate the frequency and nature of bowel disorders in children of the younger age group within 6 months after a stay in hospital for acute diarrhea and to establish their relationship with coprological indicators — fecal calprotectin (FCР), the content of carbohydrates (reducing substances, RS), lactic acid (LA) and short-chain fatty acids (SCFA) — acetic, propionic and fatty (butyric). Materials and methods. The study involved 47 children aged 6–24 months who were hospitalized for acute diarrhea. Acute enterocolitis (group I) was diagnosed in 18 patients and was caused by Campylobacter jejuni in 12 cases, Escherichia coli O-18 and Escherichia coli O-44 in 3, Salmonella enteritidis in 2 and Yersinia enterocolitica in one case. Rotaviral gastroenteritis (group II) was diagnosed in 11 patients. Another 11 children had acute symptomatic (parenteral) diarrhea (group III) against the background of intestinal infection — acute otitis, pneumonia, pyelonephritis. In 7 children, diarrhea was classified as functional digestive disorder (group IV). Routine clinical tests were supplemented with an examination of feces for the presence of intestinal parasites, Clostridium difficile A/B toxins, adenoviruses, human hemoglobin, RS, FCP, SCFA and LA. Results. Six-month follow-up established that 14 of 18 children in group I had permanent or temporary loose stools. These complaints in 13 cases were combined with episodes of abdominal pain similar to intestinal colic. The same complaints were much less frequent in children of group II (6 and 3 of 11, respectively), group III (4 and 2 of 11) and group IV (only in 2 of 7 children). The rank correlation analysis did not reveal any significant relationships between the intensity and duration of complaints and FCP, RS, LA, and SCFA in patients of groups I and II. On the contrary, in group III, there were multiple correlations of complaints with FCP, RS, LA, and SCFA. In group IV, the association of loose stools with an increase in LA and acetic acid has been found. Conclusions. According to the 6-month follow-up, 57 % of young children with acute diarrhea complained of loose stools and/or recurrent abdominal pain after discharge from the hospital. Most often, intestinal disorders were detected in children who had acute bacterial enterocolitis. There were no correlations between the intensity of post-infectious (bacterial or viral) disorders with FCP, RS, LA and SCFA during hospitalization. In contrast, such associations were numerous in children with symptomatic (parenteral) and functional diarrhea. It was suggested that the studied coprological parameters can be used to predict the state of the intestine after acute diarrhea.

Relationship between the humoral link of immunity, cytokine regulation with short-chain fatty acids in patients with inflammatory bowel diseases

Background. The pathogenesis of chronic inflammatory bowel disease (IBD) is still not fully clarified. Modern research is aimed at studying the state of humoral immunity, production and intestinal absorption of short-chain fatty acids (SCFA). The purpose was to assess the state of the humoral part of immunity, cytokine regulation and the content of short-chain fatty acids in the feces of patients with IBD. Materials and methods. The study, which was carried out at the Department of Intestinal Diseases of the Institute of Gastroenterology of the National Academy of Medical Sciences of Ukraine, involved 34 patients with IBD: groupI— those with ulcerative colitis (UC) (n=25), group II— individuals with Crohn’s disease (n=9). Determination of fecal SCFA, level of CD22+ lymphocytes, immunoglobulins A, M, G, interleukin-10 and TNF-α was determined. Results. There was a decrease in the humoral level of immunity, increase in the content of propionic (C3) acid (p&lt;0.001) and a decrease in acetic (C2) (p&lt;0.001) and butyric (C4) (p&lt;0.001) acids in the coprofiltrate of patients with IBD. The level of TNF-α was significantly higher in patients with mild UC (13.3 times, p&lt;0.05), in patients with moderate UC (17.4 times, p&lt;0.05) and in patients with Severe UC (19.4 times, p &lt;0.05) compared with its level in the control group; it was found that in the group of patients with severe UC there was a significant decrease in the content of butyric acid (C4) in 2.8 times relative to the control group (p&lt;0,01). Conclusions. In our study, a relationship was established between the level of humoral immunity, cytokine regulation and the content of FFA in feces, which may indicate the participation of intestinal metabolites in the activation of human immunity.

Clinical significance of the determination of fecal short-chain fatty acids in patients with nonalcoholic fatty liver disease

Clinical significance of the determination of fecal short-chain fatty acids in patients with nonalcoholic fatty liver disease

Parkinson's Disease Is Associated with Impaired Gut-Blood Barrier for Short-Chain Fatty Acids.

Short-chain fatty acids (SCFAs) produced by gut microbiota are reduced in feces but paradoxically increased in plasma of patients with Parkinson's disease (PD), which may stem from intestinal wall leakage. Gut function should be taken into consideration when conducting microbial-metabolite research. The objective was to investigate synchronous changes of SCFAs in feces and plasma of patients with PD, taking constipation as a confounder to better disentangle the SCFA metabolism exclusively associated with PD. The concentrations of fecal and plasma SCFAs in 33 healthy control subjects and 95 patients with PD were measured using liquid and gas chromatography mass spectrometry, respectively. Patients with PD were divided into patients with PD without constipation (n=35) and patients with PD with constipation (n=60). Gut-blood barrier (GBB) permeability was assessed by plasma/fecal ratio of SCFA concentrations and fecal α1-antitrypsin concentration. Patients with PD displayed decreased concentrations of fecal acetic, propionic, and butyric acid and increased concentrations of plasma acetic and propionic acid. Fecal acetic, isobutyric, and isovaleric acid were lower and plasma acetic and propionic acid were higher in patients with PD with constipation than in patients with PD without constipation. Constipation aggravated GBB permeability in patients with PD. Combined fecal and plasma SCFAs could discriminate patients with PD from healthy control subjects. Fecal SCFAs, except propionic acid, were negatively correlated with disease severity, while plasma acetic, propionic, and valeric acid showed a positive correlation. Our study showed alterations of fecal and plasma SCFAs in patients with PD that were associated with an impaired GBB and might be aggravated by constipation. © 2022 International Parkinson and Movement Disorder Society.

Characterization of short-chain fatty acids in patients with ulcerative colitis: a meta-analysis

BackgroundStudies investigating the changes in short-chain fatty acids (SCFAs) in patients with ulcerative colitis (UC) have yielded inconsistent results. We performed a meta-analysis of studies that investigated the alterations in different SCFAs among UC patients to assess their role in the development of UC.MethodsThree databases were searched for relevant studies published as of April 2021. Results are presented as standardized mean difference (SMD) with 95% confidence interval (95% CI).ResultsEleven studies were included in the meta-analysis. Compared to healthy subjects, UC patients had significantly lower concentrations of total SCFAs (SMD = − 0.88, 95%CI − 1.44, − 0.33; P < 0.001), acetate (SMD = − 0.54, 95% CI − 0.91, − 0.17; P = 0.004), propionate, (SMD = − 0.37, 95% CI − 0.66, − 0.07; P = 0.016), and valerate (SMD = − 0.91, 95% CI − 1.45, − 0.38; P < 0.001). On subgroup analysis based on disease status, patients with active UC had reduced concentrations of acetate (SMD = − 1.83, 95% CI − 3.32, − 0.35; P = 0.015), propionate (SMD = − 2.51, 95% CI − 4.41, − 0.61; P = 0.009), and valerate (SMD = − 0.91, 95% CI − 1.45, − 0.38; P < 0.001), while UC patients in remission had similar concentrations with healthy subjects. Patients with active UC had lower butyrate level (SMD = − 2.09, 95% CI − 3.56, − 0.62; P = 0.005) while UC patients in remission had higher butyrate level (SMD = 0.71, 95% CI 0.33, 1.10; P < 0.001) compared with healthy subjects.ConclusionUC patients had significantly decreased concentrations of total SCFAs, acetate, propionate, and valerate compared with healthy subjects. In addition, inconsistent changes of certain special SCFAs were observed in UC patients with different disease status.

Fecal Levels of Lactic, Succinic and Short-Chain Fatty Acids in Patients with Ulcerative Colitis and Crohn Disease: A Pilot Study.

Intestinal dysbiosis plays a crucial role in the development of inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC). The importance of bacterial metabolites, such as short-chain fatty acids (SCFAs), succinic and lactic acids, as well as environmental factors that affect their production in the course of IBD, remains unclear. The aim of this study was to evaluate a profile of organic acids in the stool of CD and UC patients with different disease activity. We assessed a correlation between used medications, patient’s diet, and SCFA levels. A total of 35 adult patients were included in the study. We did not observe significant differences in the levels of organic acids between the CD and UC groups, irrespective of disease activity, and a control group. However, propionic acid levels were higher in IBD patients who received trimebutine vs. those who did not (p = 0.031). Higher isobutyric acid levels were observed in patients treated with biological drugs compared with those without such treatment (p = 0.014). No significant correlations were found between organic acid levels and the frequency of dietary fiber consumption. Our results reveal a new link between medication use and organic acid levels in patients with IBD.

Короткоцепочечные жирные кислоты: роль в развитии синдрома раздраженного кишечника

В статье рассматриваются вопросы патогенеза синдрома раздраженного кишечника. Проведен короткий анализ вероятных факторов развития синдрома раздраженного кишечника. Отдельно рассмотрена роль кишечной микрофлоры и вклад короткоцепочечных жирных кислот в процессы, происходящие при синдроме раздраженного кишечника. Проанализованы исследования различных авторов относительно короткоцепочечных жирных кислот. Показаны результаты собственных исследований, в которых опеределялось содержание в кале короткоцепочечных жирных кислот у больных с синдромом раздраженного кишечника. Было выявлено существенное повышение содержания короткоцепочечных жирных кислот, особенно при диарейной форме синдрома раздраженного кишечника.

Характеристика состояния кишечной микрофлоры и содержания короткоцепочечных жирных кислот у больных с синдромом раздраженного кишечника

В статье рассматриваются вопросы, связанные с кишечной микрофлорой и короткоцепочечными жирными кислотами у больных с синдромом раздраженного кишечника. Установлено, что концентрация уксусной, пропионовой, масляной кислот в кале выше у больных с синдромом раздраженного кишечника с диареей по сравнению с больными без диарейного синдрома. У 83,3–88,9 % больных с различными формами синдрома раздраженного кишечника наблюдаются дисбиотические изменения; у пациентов с диарейной формой чаще отмечается пониженное содержание бифидобактерий и, особенно, лактобактерий. Отмечается определенная взаимозависимость между концентрацией короткоцепочечных жирных кислот и содержанием бифидобактерий, лактобактерий, кандидозной и условно-патогенной флоры.

Altered synthesis of genes associated with short-chain fatty acids in the gut of patients with atrial fibrillation

BackgroundThe gut microbiota provides health benefits in humans by producing short-chain fatty acids (SCFAs), whose deficiency causes multiple disorders and inflammatory diseases. However, gut bacteria producing SCFAs in patients with atrial fibrillation (AF), an arrhythmia with increasing prevalence, have not been reported. To investigate major gut microbial organisms related to SCFA synthesis, SCFAs-associated KEGG orthologues (KOs), enzymatic genes, and potential producers were examined according to metagenomic data-mining in a northern Chinese cohort comprising 50 non-AF control and 50 AF patients.ResultsCompared with non-AF controls, individuals with AF had marked differences in microbial genes involved in SCFA-related synthesis, including 125 KOs and 5 SCFAs-related enzymatic genes. Furthermore, there were 10 species that harbored SCFA-synthesis related enzymatic genes, and were markedly decreased in the gut of AF patients. Notably, discriminative features about SCFA-synthesis related function, including 8 KOs (K01752, K01738, K00175, K03737, K01006, K01653, K01647 and K15023), 4 genes (menI, tesB, yciA and CO dehydrogenase acetyl-CoA synthase complex) and 2 species (Coprococcus catus and Firmicutes bacterium CAG:103), were selected as key factors based on LASSO analysis. Furthermore, PLS-SEM analysis showed that 72.8 and 91.14 % of the overall effects on gut microbiota diversity and key species on AF, respectively, were mediated by the key KOs. Meanwhile, 46.31 % of the total effects of SCFA-synthesis related function on left atrial enlargement was mediated by hsCRP. Upon incorporation of clinical properties in AF, the KO score was still significantly associated with AF incidence (OR = 0.004, P = 0.001).ConclusionsThe current study revealed that dysbiotic gut microbiota in AF is coupled with disrupted SCFA-synthesis related genes, characterized by decreased abundances of KEGG orthologues, synthesis enzymatic genes and harboring species.

Features of dysbiotic changes of the large intestine and indicators of short-chain fatty acids in patients with chronic inflammatory bowel disease depending on the nutritional status

Features of dysbiotic changes of the large intestine and indicators of short-chain fatty acids in patients with chronic inflammatory bowel disease depending on the nutritional status