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Cell Communication and Signaling : CCS Aug 2023Short-chain fatty acids (SCFAs) are the main metabolites produced by bacterial fermentation of dietary fibre in the gastrointestinal tract. The absorption of SCFAs is... (Review)
Review
Short-chain fatty acids (SCFAs) are the main metabolites produced by bacterial fermentation of dietary fibre in the gastrointestinal tract. The absorption of SCFAs is mediated by substrate transporters, such as monocarboxylate transporter 1 and sodium-coupled monocarboxylate transporter 1, which promote cellular metabolism. An increasing number of studies have implicated metabolites produced by microorganisms as crucial executors of diet-based microbial influence on the host. SCFAs are important fuels for intestinal epithelial cells (IECs) and represent a major carbon flux from the diet, that is decomposed by the gut microbiota. SCFAs play a vital role in multiple molecular biological processes, such as promoting the secretion of glucagon-like peptide-1 by IECs to inhibit the elevation of blood glucose, increasing the expression of G protein-coupled receptors such as GPR41 and GPR43, and inhibiting histone deacetylases, which participate in the regulation of the proliferation, differentiation, and function of IECs. SCFAs affect intestinal motility, barrier function, and host metabolism. Furthermore, SCFAs play important regulatory roles in local, intermediate, and peripheral metabolisms. Acetate, propionate, and butyrate are the major SCFAs, they are involved in the regulation of immunity, apoptosis, inflammation, and lipid metabolism. Herein, we review the diverse functional roles of this major class of bacterial metabolites and reflect on their ability to affect intestine, metabolic, and other diseases. Video Abstract.
Topics: Fatty Acids, Volatile; Butyrates; Propionates; Gastrointestinal Tract; Apoptosis
PubMed: 37596634
DOI: 10.1186/s12964-023-01219-9 -
Circulation Research Sep 2022Preeclampsia is one of the leading causes of maternal and perinatal morbidity and is characterized by hypertension, inflammation, and placental dysfunction. Gut...
BACKGROUND
Preeclampsia is one of the leading causes of maternal and perinatal morbidity and is characterized by hypertension, inflammation, and placental dysfunction. Gut microbiota plays key roles in inflammation and hypertension. However, its roles and mechanisms in preeclampsia have not been fully elucidated.
METHODS
16S rRNA gene sequencing and targeted metabolomics were conducted on stool samples from 92 preeclamptic patients and 86 normal late-pregnant women. Then, fecal microbiota transplantation and in vitro and in vivo functional experiments were performed to explore the roles and mechanisms of gut microbiota in preeclampsia development.
RESULTS
We revealed the gut microbiota dysbiosis in preeclamptic patients, including significant reductions in short-chain fatty acid-producing bacteria and short-chain fatty acids. The gut microbiota of preeclamptic patients significantly exacerbated pathologies and symptoms of preeclamptic rats, whereas the gut microbiota of healthy pregnant women had significant protective effects. , propionate, or butyrate significantly alleviated the symptoms of preeclamptic rats. Mechanistically, they significantly promoted autophagy and M2 polarization of macrophages in placental bed, thereby suppressing inflammation. Propionate also significantly promoted trophoblast invasion, thereby improved spiral arterial remodeling. Additionally, we identified a marker set consisting of , , and short-chain fatty acids that could accurately diagnose preeclampsia.
CONCLUSIONS
Our study revealed that gut microbiota dysbiosis is an important etiology of preeclampsia. Gut microbiota and their active metabolites have great potential for the treatment and diagnosis of preeclampsia. Our findings enrich the gut-placenta axis theory and contribute to the development of microecological products for preeclampsia.
Topics: Animals; Dysbiosis; Fatty Acids, Volatile; Female; Humans; Hypertension; Inflammation; Macrophages; Placenta; Pre-Eclampsia; Pregnancy; Propionates; RNA, Ribosomal, 16S; Rats; Trophoblasts
PubMed: 35950704
DOI: 10.1161/CIRCRESAHA.122.320771 -
European Heart Journal Feb 2022Atherosclerotic cardiovascular disease (ACVD) is a major cause of mortality and morbidity worldwide, and increased low-density lipoproteins (LDLs) play a critical role... (Randomized Controlled Trial)
Randomized Controlled Trial
AIMS
Atherosclerotic cardiovascular disease (ACVD) is a major cause of mortality and morbidity worldwide, and increased low-density lipoproteins (LDLs) play a critical role in development and progression of atherosclerosis. Here, we examined for the first time gut immunomodulatory effects of the microbiota-derived metabolite propionic acid (PA) on intestinal cholesterol metabolism.
METHODS AND RESULTS
Using both human and animal model studies, we demonstrate that treatment with PA reduces blood total and LDL cholesterol levels. In apolipoprotein E-/- (Apoe-/-) mice fed a high-fat diet (HFD), PA reduced intestinal cholesterol absorption and aortic atherosclerotic lesion area. Further, PA increased regulatory T-cell numbers and interleukin (IL)-10 levels in the intestinal microenvironment, which in turn suppressed the expression of Niemann-Pick C1-like 1 (Npc1l1), a major intestinal cholesterol transporter. Blockade of IL-10 receptor signalling attenuated the PA-related reduction in total and LDL cholesterol and augmented atherosclerotic lesion severity in the HFD-fed Apoe-/- mice. To translate these preclinical findings to humans, we conducted a randomized, double-blinded, placebo-controlled human study (clinical trial no. NCT03590496). Oral supplementation with 500 mg of PA twice daily over the course of 8 weeks significantly reduced LDL [-15.9 mg/dL (-8.1%) vs. -1.6 mg/dL (-0.5%), P = 0.016], total [-19.6 mg/dL (-7.3%) vs. -5.3 mg/dL (-1.7%), P = 0.014] and non-high-density lipoprotein cholesterol levels [PA vs. placebo: -18.9 mg/dL (-9.1%) vs. -0.6 mg/dL (-0.5%), P = 0.002] in subjects with elevated baseline LDL cholesterol levels.
CONCLUSION
Our findings reveal a novel immune-mediated pathway linking the gut microbiota-derived metabolite PA with intestinal Npc1l1 expression and cholesterol homeostasis. The results highlight the gut immune system as a potential therapeutic target to control dyslipidaemia that may introduce a new avenue for prevention of ACVDs.
Topics: Animals; Apolipoproteins E; Atherosclerosis; Cholesterol; Cholesterol, LDL; Humans; Intestinal Absorption; Mice; Mice, Inbred C57BL; Mice, Knockout; Propionates
PubMed: 34597388
DOI: 10.1093/eurheartj/ehab644 -
Cell Mar 2020Short-chain fatty acids are processed from indigestible dietary fibers by gut bacteria and have immunomodulatory properties. Here, we investigate propionic acid (PA) in...
Short-chain fatty acids are processed from indigestible dietary fibers by gut bacteria and have immunomodulatory properties. Here, we investigate propionic acid (PA) in multiple sclerosis (MS), an autoimmune and neurodegenerative disease. Serum and feces of subjects with MS exhibited significantly reduced PA amounts compared with controls, particularly after the first relapse. In a proof-of-concept study, we supplemented PA to therapy-naive MS patients and as an add-on to MS immunotherapy. After 2 weeks of PA intake, we observed a significant and sustained increase of functionally competent regulatory T (Treg) cells, whereas Th1 and Th17 cells decreased significantly. Post-hoc analyses revealed a reduced annual relapse rate, disability stabilization, and reduced brain atrophy after 3 years of PA intake. Functional microbiome analysis revealed increased expression of Treg-cell-inducing genes in the intestine after PA intake. Furthermore, PA normalized Treg cell mitochondrial function and morphology in MS. Our findings suggest that PA can serve as a potent immunomodulatory supplement to MS drugs.
Topics: Adult; Aged; Disease Progression; Feces; Female; Humans; Immunomodulation; Male; Middle Aged; Multiple Sclerosis; Neurodegenerative Diseases; Propionates; T-Lymphocytes, Regulatory; Th17 Cells
PubMed: 32160527
DOI: 10.1016/j.cell.2020.02.035 -
Skin Therapy Letter Jan 2022The pathogenesis of acne is multifactorial and involves inflammation, bacterial dysbiosis, and androgen stimulation. Existing systemic therapies target hormonal pathways...
The pathogenesis of acne is multifactorial and involves inflammation, bacterial dysbiosis, and androgen stimulation. Existing systemic therapies target hormonal pathways to mitigate acne lesions; however, their use is limited to the female population and associated with systemic adverse effects. Clascoterone is the first topical therapy to target the hormonal pathogenesis of acne approved to treat acne vulgaris. In two identical phase 3 trials, clascoterone showed favorable efficacy over placebo in treating acne, with higher treatment success and a greater reduction in acne lesions. Large scale trials are required to assess the efficacy of clascoterone against its comparators and in combination with existing acne therapies; however, results from the current phase 3 trials support the therapeutic value of clascoterone, suggesting that this novel topical androgen inhibitor represents a valuable addition to the catalogue of acne therapy.
Topics: Acne Vulgaris; Administration, Topical; Cortodoxone; Female; Humans; Propionates; Treatment Outcome
PubMed: 35081302
DOI: No ID Found -
Military Medical Research Aug 2022Wear particles-induced osteolysis is a major long-term complication after total joint arthroplasty. Up to now, there is no effective treatment for wear particles-induced...
BACKGROUND
Wear particles-induced osteolysis is a major long-term complication after total joint arthroplasty. Up to now, there is no effective treatment for wear particles-induced osteolysis except for the revision surgery, which is a heavy psychological and economic burden to patients. A metabolite of gut microbiota, short chain fatty acids (SCFAs), has been reported to be beneficial for many chronic inflammatory diseases. This study aimed to investigate the therapeutic effect of SCFAs on osteolysis.
METHODS
A model of inflammatory osteolysis was established by applying CoCrMo alloy particles to mouse calvarium. After two weeks of intervention, the anti-inflammatory effects of SCFAs on wear particle-induced osteolysis were evaluated by Micro-CT analysis and immunohistochemistry staining. In vitro study, lipopolysaccharide (LPS) primed bone marrow-derived macrophages (BMDMs) and Tohoku Hospital Pediatrics-1 (THP-1) macrophages were stimulated with CoCrMo particles to activate inflammasome in the presence of acetate (C2), propionate (C3), and butyrate (C4). Western blotting, Enzyme-linked immunosorbent assay, and immunofluorescence were used to detect the activation of NLRP3 inflammasome. The effects of SCFAs on osteoclasts were evaluate by qRT-PCR, Western blotting, immunofluorescence, and tartrate-resistant acid phosphatase (TRAP) staining. Additionally, histone deacetylase (HDAC) inhibitors, agonists of GPR41, GPR43, and GPR109A were applied to confirm the underlying mechanism of SCFAs on the inflammasome activation of macrophages and osteoclastogenesis.
RESULTS
C3 and C4 but not C2 could alleviate wear particles-induced osteolysis with fewer bone erosion pits (P < 0.001), higher level of bone volume to tissue volume (BV/TV, P < 0.001), bone mineral density (BMD, P < 0.001), and a lower total porosity (P < 0.001). C3 and C4 prevented CoCrMo alloy particles-induced ASC speck formation and nucleation-induced oligomerization, suppressing the cleavage of caspase-1 (P < 0.05) and IL-1β (P < 0.05) stimulated by CoCrMo alloy particles. C3 and C4 also inhibited the generation of Gasdermin D-N-terminal fragment (GSDMD-NT) to regulate pyroptosis. Besides, C3 and C4 have a negative impact on osteoclast differentiation (P < 0.05) and its function (P < 0.05), affecting the podosome arrangement and morphologically normal podosome belts formation.
CONCLUSION
Our work showed that C3 and C4 are qualified candidates for the treatment of wear particle-induced osteolysis.
Topics: Alloys; Animals; Butyrates; Humans; Inflammasomes; Macrophages; Mice; Osteogenesis; Osteolysis; Propionates; Pyroptosis
PubMed: 35996168
DOI: 10.1186/s40779-022-00404-0 -
Microbiome Feb 2023Gut homeostasis, including intestinal immunity and microbiome, is essential for cognitive function via the gut-brain axis. This axis is altered in high-fat diet...
BACKGROUND
Gut homeostasis, including intestinal immunity and microbiome, is essential for cognitive function via the gut-brain axis. This axis is altered in high-fat diet (HFD)-induced cognitive impairment and is closely associated with neurodegenerative diseases. Dimethyl itaconate (DI) is an itaconate derivative and has recently attracted extensive interest due to its anti-inflammatory effect. This study investigated whether intraperitoneal administration of DI improves the gut-brain axis and prevents cognitive deficits in HF diet-fed mice.
RESULTS
DI effectively attenuated HFD-induced cognitive decline in behavioral tests of object location, novel object recognition, and nesting building, concurrent with the improvement of hippocampal RNA transcription profiles of genes associated with cognition and synaptic plasticity. In agreement, DI reduced the damage of synaptic ultrastructure and deficit of proteins (BDNF, SYN, and PSD95), the microglial activation, and neuroinflammation in the HFD-fed mice. In the colon, DI significantly lowered macrophage infiltration and the expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) in mice on the HF diet, while upregulating the expression of immune homeostasis-related cytokines (IL-22, IL-23) and antimicrobial peptide Reg3γ. Moreover, DI alleviated HFD-induced gut barrier impairments, including elevation of colonic mucus thickness and expression of tight junction proteins (zonula occludens-1, occludin). Notably, HFD-induced microbiome alteration was improved by DI supplementation, characterized by the increase of propionate- and butyrate-producing bacteria. Correspondingly, DI increased the levels of propionate and butyrate in the serum of HFD mice. Intriguingly, fecal microbiome transplantation from DI-treated HF mice facilitated cognitive variables compared with HF mice, including higher cognitive indexes in behavior tests and optimization of hippocampal synaptic ultrastructure. These results highlight the gut microbiota is necessary for the effects of DI in improving cognitive impairment.
CONCLUSIONS
The present study provides the first evidence that DI improves cognition and brain function with significant beneficial effects via the gut-brain axis, suggesting that DI may serve as a novel drug for treating obesity-associated neurodegenerative diseases. Video Abstract.
Topics: Mice; Animals; Diet, High-Fat; Brain-Gut Axis; Obesity; Propionates; Cognitive Dysfunction; Cytokines; Butyrates; Mice, Inbred C57BL
PubMed: 36810115
DOI: 10.1186/s40168-023-01471-8 -
Molecules (Basel, Switzerland) Jan 2021Worldwide obesity is a public health concern that has reached pandemic levels. Obesity is the major predisposing factor to comorbidities, including type 2 diabetes,... (Review)
Review
Worldwide obesity is a public health concern that has reached pandemic levels. Obesity is the major predisposing factor to comorbidities, including type 2 diabetes, cardiovascular diseases, dyslipidemia, and non-alcoholic fatty liver disease. The common forms of obesity are multifactorial and derive from a complex interplay of environmental changes and the individual genetic predisposition. Increasing evidence suggest a pivotal role played by alterations of gut microbiota (GM) that could represent the causative link between environmental factors and onset of obesity. The beneficial effects of GM are mainly mediated by the secretion of various metabolites. Short-chain fatty acids (SCFAs) acetate, propionate and butyrate are small organic metabolites produced by fermentation of dietary fibers and resistant starch with vast beneficial effects in energy metabolism, intestinal homeostasis and immune responses regulation. An aberrant production of SCFAs has emerged in obesity and metabolic diseases. Among SCFAs, butyrate emerged because it might have a potential in alleviating obesity and related comorbidities. Here we reviewed the preclinical and clinical data that contribute to explain the role of butyrate in this context, highlighting its crucial contribute in the diet-GM-host health axis.
Topics: Acetates; Animals; Butyrates; Dietary Fiber; Energy Metabolism; Fatty Acids, Volatile; Gastrointestinal Microbiome; Humans; Obesity; Propionates; Protective Agents
PubMed: 33525625
DOI: 10.3390/molecules26030682 -
The Journal of Experimental Medicine Oct 2022Microbial dysbiosis in the skin has been implicated in the pathogenesis of atopic dermatitis (AD); however, whether and how changes in the skin microbiome initiate skin...
Microbial dysbiosis in the skin has been implicated in the pathogenesis of atopic dermatitis (AD); however, whether and how changes in the skin microbiome initiate skin inflammation, or vice versa, remains poorly understood. Here, we report that the levels of sebum and its microbial metabolite, propionate, were lower on the skin surface of AD patients compared with those of healthy individuals. Topical propionate application attenuated skin inflammation in mice with MC903-induced AD-like dermatitis by inhibiting IL-33 production in keratinocytes, an effect that was mediated through inhibition of HDAC and regulation of the AhR signaling pathway. Mice lacking sebum spontaneously developed AD-like dermatitis, which was improved by topical propionate application. A proof-of-concept clinical study further demonstrated the beneficial therapeutic effects of topical propionate application in AD patients. In summary, we have uncovered that the dysregulated sebum-microbial metabolite-IL-33 axis might play an initiating role in AD-related skin inflammation, thereby highlighting novel therapeutic strategies for the treatment of AD.
Topics: Animals; Dermatitis, Atopic; Disease Models, Animal; Inflammation; Interleukin-33; Keratinocytes; Mice; Propionates; Sebum; Skin
PubMed: 35977109
DOI: 10.1084/jem.20212397 -
Nature Metabolism Apr 2022The alteration of metabolic pathways is a critical strategy for cancer cells to attain the traits necessary for metastasis in disease progression. Here, we find that...
The alteration of metabolic pathways is a critical strategy for cancer cells to attain the traits necessary for metastasis in disease progression. Here, we find that dysregulation of propionate metabolism produces a pro-aggressive signature in breast and lung cancer cells, increasing their metastatic potential. This occurs through the downregulation of methylmalonyl coenzyme A epimerase (MCEE), mediated by an extracellular signal-regulated kinase 2-driven transcription factor Sp1/early growth response protein 1 transcriptional switch driven by metastatic signalling at its promoter level. The loss of MCEE results in reduced propionate-driven anaplerotic flux and intracellular and intratumoral accumulation of methylmalonic acid, a by-product of propionate metabolism that promotes cancer cell invasiveness. Altogether, we present a previously uncharacterized dysregulation of propionate metabolism as an important contributor to cancer and a valuable potential target in the therapeutic treatment of metastatic carcinomas.
Topics: Humans; Methylmalonic Acid; Neoplasms; Phenotype; Propionates; Signal Transduction
PubMed: 35361954
DOI: 10.1038/s42255-022-00553-5