Alpha-Linolenic Acid Alleviates Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice

Dietary α-linolenic acid supplementation enhances resistance to Salmonella Typhimurium challenge in chickens by altering the intestinal mucosal barrier integrity and cecal microbes

Salmonella is an important foodborne pathogen. Given the ban on the use of antibiotics during the egg-laying period in China, finding safe and effective alternatives to antibiotics to reduce Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) infections in chickens is essential for the prevention and control of this pathogen and the protection of human health. Numerous studies have shown that unsaturated fatty acids have a positive effect on intestinal inflammation and resistance to infection by intestinal pathogens. Here we investigated the protective effect of α-linolenic acid (ALA) against S. Typhimurium infection in chickens and further explored its mechanism of action. We added different proportions of ALA to the feed and observed the effect of ALA on S. Typhimurium colonization using metagenomic sequencing technology and physiological index measurements. The role of gut flora on S. Typhimurium colonization was subsequently verified by fecal microbiota transplantation (FMT). We found that ALA protects chickens from S. Typhimurium infection by reducing intestinal inflammation through remodeling the gut microbiota, up-regulating the expression of ileocecal barrier-related genes, and maintaining the integrity of the intestinal epithelium. Our data suggest that supplementation of feed with ALA may be an effective strategy to alleviate S. Typhimurium infection in chickens.

Current Knowledge on the Preparation and Benefits of Cruciferous Vegetables as Relates to In Vitro, In Vivo, and Clinical Models of Inflammatory Bowel Disease

Inflammatory bowel disease is a chronic condition with a significant economic and social burden. The disease is complex and challenging to treat because it involves several pathologies, such as inflammation, oxidative stress, dysbiosis, and intestinal damage. The search for an effective treatment has identified cruciferous vegetables and their phytochemicals as potential management options for inflammatory bowel disease because they contain prebiotics, probiotics, and anti-inflammatory and antioxidant metabolites essential for a healthy gut. This critical narrative style review provides a robust insight into the pharmacological effects and benefits of crucifers and their documented bioactive compounds in in vitro and in vivo models, as well as clinical inflammatory bowel disease. The review highlights the significant impact of crucifer preparation and the presence of glucosinolates, isothiocyanates, flavonoids, and polyphenolic compounds, which are essential for the anti-inflammatory and antioxidative benefits of cruciferous vegetables, as well as their ability to promote the healthy microbial community and maintain the intestinal barrier. This review may serve as a viable nutritional guide for future research on methods and features essential to developing experiments, preventions, and treatments for inflammatory bowel disease. There is limited clinical information and future research may utilize current innovative tools, such as metabolomics, for adequate knowledge and effective translation into clinical therapy.

The genus Actinidia Lindl. (Actinidiaceae): A comprehensive review on its ethnobotany, phytochemistry, and pharmacological properties

ETHNOPHARMACOLOGICAL RELEVANCE

Actinidia Lindl. belongs to the family Actinidiaceae. Plants of this genus are popularly known as kiwifruits and are traditionally used to treat a wide range of ailments associated with digestive disorders, rheumatism, kidney problems, cardiovascular system, cancers, dyspepsia, hemorrhoids, and diabetes among others.

AIM

This review discusses the ethnobotanical uses, phytochemical profile, and known pharmacological properties of Actinidia plants, to understand their connotations and provide the scientific basis for future studies.

MATERIALS AND METHODS

The data were obtained by surveying journal articles, books, and dissertations using various search engines such as Google Scholar, PubMed, Science Direct, Springer Link, and Web of Science. The online databases; World Flora Online, Plants of the World Online, International Plant Names Index, and Global Biodiversity Information Facility were used to confirm the distribution and validate scientific names of Actinidia plants. The isolated metabolites from these species were illustrated using ChemBio Draw ultra-version 14.0 software.

RESULTS

Ten (10) species of Actinidia genus have been reported as significant sources of traditional medicines utilized to remedy diverse illnesses. Our findings revealed that a total of 873 secondary metabolites belonging to different classes such as terpenoids, phenolic compounds, alcohols, ketones, organic acids, esters, hydrocarbons, and steroids have been isolated from different species of Actinidia. These compounds were mainly related to the exhibited antioxidant, antimicrobial, anti-inflammatory, antidiabetic, antiproliferative, anti-angiogenic, anticinoceptive, anti-tumor, and anticancer activities.

CONCLUSION

This study assessed the information related to the ethnobotanical uses, phytochemical compounds, and pharmacological properties of Actinidia species, which indicate that they possess diverse bioactive metabolites with interesting bioactivities. Actinidia plants have great potential for applications in folklore medicines and pharmaceuticals due to their wide ethnomedicinal uses and biological activities. Traditional uses of several Actinidia species are supported by scientific evidences, qualifying them as possible modern remedies for various ailments. Nonetheless, the currently available data has several gaps in understanding the herbal utilization of most Actinidia species. Thus, further research into their toxicity, mechanisms of actions of the isolated bioactive metabolites, as well as scientific connotations between the traditional medicinal uses and pharmacological properties is required to unravel their efficacy in therapeutic potential for safe clinical application.

Gut microbiota-related metabolite alpha-linolenic acid mitigates intestinal inflammation induced by oral infection with Toxoplasma gondii

BACKGROUND

Oral infection with cysts is the main transmission route of Toxoplasma gondii (T. gondii), which leads to lethal intestinal inflammation. It has been widely recognized that T. gondii infection alters the composition and metabolism of the gut microbiota, thereby affecting the progression of toxoplasmosis. However, the potential mechanisms remain unclear. In our previous study, there was a decrease in the severity of toxoplasmosis after T. gondii α-amylase (α-AMY) was knocked out. Here, we established mouse models of ME49 and Δα-amy cyst infection and then took advantage of 16S rRNA gene sequencing and metabolomics analysis to identify specific gut microbiota-related metabolites that mitigate T. gondii-induced intestinal inflammation and analyzed the underlying mechanism.

RESULTS

There were significant differences in the intestinal inflammation between ME49 cyst- and Δα-amy cyst-infected mice, and transferring feces from mice infected with Δα-amy cysts into antibiotic-treated mice mitigated colitis caused by T. gondii infection. 16S rRNA gene sequencing showed that the relative abundances of gut bacteria, such as Lactobacillus and Bacteroides, Bifidobacterium, [Prevotella], Paraprevotella and Macellibacteroides, were enriched in mice challenged with Δα-amy cysts. Spearman correlation analysis between gut microbiota and metabolites indicated that some fatty acids, including azelaic acid, suberic acid, alpha-linolenic acid (ALA), and citramalic acid, were highly positively correlated with the identified bacterial genera. Both oral administration of ALA and fecal microbiota transplantation (FMT) decreased the expression of pro-inflammatory cytokines and restrained the MyD88/NF-κB pathway, which mitigated colitis and ultimately improved host survival. Furthermore, transferring feces from mice treated with ALA reshaped the colonization of beneficial bacteria, such as Enterobacteriaceae, Proteobacteria, Shigella, Lactobacillus, and Enterococcus.

CONCLUSIONS

The present findings demonstrate that the host gut microbiota is closely associated with the severity of T. gondii infection. We provide the first evidence that ALA can alleviate T. gondii-induced colitis by improving the dysregulation of the host gut microbiota and suppressing the production of pro-inflammatory cytokines via the MyD88/NF-κB pathway. Our study provides new insight into the medical application of ALA for the treatment of lethal intestinal inflammation caused by Toxoplasma infection. Video Abstract.

Fatty acids and lipid mediators in inflammatory bowel disease: from mechanism to treatment

Inflammatory Bowel Disease (IBD) is a chronic, relapsing inflammatory disorder of the gastrointestinal tract. Though the pathogenesis of IBD remains unclear, diet is increasingly recognized as a pivotal factor influencing its onset and progression. Fatty acids, essential components of dietary lipids, play diverse roles in IBD, ranging from anti-inflammatory and immune-regulatory functions to gut-microbiota modulation and barrier maintenance. Short-chain fatty acids (SCFAs), products of indigestible dietary fiber fermentation by gut microbiota, have strong anti-inflammatory properties and are seen as key protective factors against IBD. Among long-chain fatty acids, saturated fatty acids, trans fatty acids, and ω-6 polyunsaturated fatty acids exhibit pro-inflammatory effects, while oleic acid and ω-3 polyunsaturated fatty acids display anti-inflammatory actions. Lipid mediators derived from polyunsaturated fatty acids serve as bioactive molecules, influencing immune cell functions and offering both pro-inflammatory and anti-inflammatory benefits. Recent research has also highlighted the potential of medium- and very long-chain fatty acids in modulating inflammation, mucosal barriers, and gut microbiota in IBD. Given these insights, dietary intervention and supplementation with short-chain fatty acids are emerging as potential therapeutic strategies for IBD. This review elucidates the impact of various fatty acids and lipid mediators on IBD and delves into potential therapeutic avenues stemming from these compounds.

Improved colonic inflammation by nervonic acid via inhibition of NF-κB signaling pathway of DSS-induced colitis mice

BACKGROUND

Nervonic acid (C24:1^∆15, 24:1 ω-9, cis-tetracos-15-enoic acid; NA), a long-chain monounsaturated fatty acid, plays an essential role in prevention of metabolic diseases, and immune regulation, and has anti-inflammatory properties. As a chronic, immune-mediated inflammatory disease, ulcerative colitis (UC) can affect the large intestine. The influences of NA on UC are largely unknown.

PURPOSE

The present study aimed to decipher the anti-UC effect of NA in the mouse colitis model. Specifically, we wanted to explore whether NA can regulate the levels of inflammatory factors in RAW264.7 cells and mouse colitis model.

METHODS

To address the above issues, the RAW264.7 cell inflammation model was established by lipopolysaccharide (LPS), then the inflammatory factors tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β (IL-1β), and Interleukin-10 (IL-10) were detected by Enzyme-linked immunosorbent assay (ELISA). The therapeutic effects of NA for UC were evaluated using C57BL/6 mice gavaged dextran sodium sulfate (DSS). Hematoxylin and eosin (H&E) staining, Myeloperoxidase (MPO) kit assay, ELISA, immunofluorescence assay, and LC-MS/MS were used to assess histological changes, MPO levels, inflammatory factors release, expression and distribution of intestinal tight junction (TJ) protein ZO-1, and metabolic pathways, respectively. The levels of proteins involved in the nuclear factor kappa-B (NF-κB) pathway in the UC were investigated by western blotting and RT-qPCR.

RESULTS

In vitro experiments verified that NA could reduce inflammatory response and inhibit the activation of key signal pathways associated with inflammation in LPS-induced RAW264.7 cells. Further, results from the mouse colitis model suggested that NA could restore intestinal barrier function and suppress NF-κB signal pathways to ameliorate DSS-induced colitis. In addition, untargeted metabolomics analysis of NA protection against UC found that NA protected mice from colitis by regulating citrate cycle, amino acid metabolism, pyrimidine and purine metabolism.

CONCLUSION

These results suggested that NA could ameliorate the secretion of inflammatory factors, suppress the NF-κB signaling pathway, and protect the integrity of colon tissue, thereby having a novel role in prevention or treatment therapy for UC. This work for the first time indicated that NA might be a potential functional food ingredient for preventing and treating inflammatory bowel disease (IBD).

Perilla frutescens: A traditional medicine and food homologous plant

Perilla frutescens, an annual herb of the Labiatae family, has been cultivated in China for more than 2000 years. P. frutescens is the one of the first medicinal and edible plant published by the Ministry of Health. Its leaves, stems and seeds can be used as medicine and edible food. Because of the abundant nutrients and bioactive components in this plant, P. frutescens has been studied extensively in medicine, food, health care and chemical fields with great prospects for development. This paper reviews the cultivation history, chemical compositions and pharmacological activities of P. frutescens, which provides a reference for the development and utilization of P. frutescens resources.

Novel evaluation indicators of MOG35∼55 induced experimental autoimmune encephalomyelitis in C57BL/6J mice

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS), characterized by demyelinating neuropathy. Despite a long period of research on the immune mechanisms involved in CNS diseases, the etiology of MS remains unknown. MS may present with different clinical and pathological manifestations due to the involvement of different pathogenic processes, including balance and mobility disorders, psychiatric abnormalities, and intestinal dysfunction. We used an animal model of MS, experimental autoimmune encephalomyelitis (EAE), to assess clinical symptoms of MS with the aim of creating new indicators for the assessment of EAE. Our results show that EAE mice develop severe bone loss, anxiety-like moods, and intestinal inflammation in addition to clinical phenomena such as inflammatory infiltration and demyelination of the spinal cord. Our new indicators aim to provide a more comprehensive assessment of MS to avoid the pitfalls of a single intervention and also to provide a more systematic assessment of the effectiveness of drugs used to treat MS.

Comprehensive analysis of microbiome, metabolome and transcriptome revealed the mechanisms of Moringa oleifera polysaccharide on preventing ulcerative colitis

This study aimed to investigate the protective effect of Moringa oleifera polysaccharide (MOP) on ulcerative colitis (UC) and explore its mechanism through the combined analysis of microbiome, metabolome and transcriptome. A UC model in mice was established using dextran sulphate sodium. After a 21-day experiment, results showed that MOP could inhibit the weight loss and disease activity index in UC mice. The intervention of MOP decreased the expression of inflammatory cytokines and promoted the secretion of tight junctions. MOP could promote the growth of probiotics such as Lachnospiraceae_NK4A136, Intestinimonas and Bifidobacterium in UC mice. The results of metabolomic and transcriptomic analysis indicated that MOP could regulated the metabolism of polyunsaturated fatty acid and PPAR, TLR and TNF signalling pathways might play important roles in the process. Altogether, MOP could be used as a functional food to prevent UC.

Dietary α-Linolenic Acid-Rich Flaxseed Oil Ameliorates High-Fat Diet-Induced Atherosclerosis via Gut Microbiota-Inflammation-Artery Axis in ApoE−/− Mice

Atherosclerosis (AS) is closely associated with abnormally chronic low-grade inflammation and gut dysbiosis. Flaxseed oil (FO) rich in omega-3 polyunsaturated fatty acids (PUFAs), which are mainly composed of alpha-linolenic acid (ALA, 18:3 omega-3), has been demonstrated to exhibit pleiotropic benefits in chronic metabolic diseases. However, the impact of dietary ALA-rich FO on AS and its associated underlying mechanisms remain poorly understood. Thus, the present study was designed as two phases to investigate the effects in atherosclerotic Apolipoprotein E (ApoE)^−/− mice. In the initial portion, the ApoE^−/− mice were randomly allocated to three groups: control group (CON), model group (MOD), and FO-fed model group (MOD/FO) and were treated for 12 weeks. The second phase used antibiotic (AB)-treated ApoE^−/− mice were divided into two groups: AB-treated model group (AB/MOD) and FO-fed AB-treated model group (AB/FO). In the results, the dietary ALA-rich FO administration ameliorated atherosclerotic lesion, as well as the parameters of AS (body weights (BWs) and the total bile acids (TBA). Chronic systemic/vascular inflammatory cytokines and in situ macrophages (Mψs) were reduced with FO intervention. In addition, the FO improved the gut integrity and permeability by decreasing the plasma lipopolysaccharide (LPS). Moreover, gut dysbiosis and metabolites [short-chain fatty acids (SCFAs) and bile acids (BAs)] in AS were modulated after FO treatment. Intriguingly, during an AB-treated condition, a significantly weakened amelioration of FO-treated on AS proposed that the intestinal microbiota contributed to the FO effects. A correlation analysis showed close relationships among gut bacteria, metabolites, and inflammation. Collectively, these results suggested that the dietary ALA-rich FO ameliorated the AS in ApoE^−/− mice via the gut microbiota-inflammation-artery axis.

Advances in Research on Chemical Constituents and Their Biological Activities of the Genus Actinidia

Kiwi, a fruit from plants of the genus Actinidia, is one of the famous fruits with thousand years of edible history. In the past twenty years, a great deal of research has been done on the chemical constituents of the Actinidia species. A large number of secondary metabolites including triterpenoids, flavonoids, phenols, etc. have been identified from differents parts of Actinidia plants, which exhibited significant in vitro and in vivo pharmacological activities including anticancer, anti-inflammatory, neuroprotective, anti-oxidative, anti-bacterial, and anti-diabetic activities. In order to fully understand the chemical components and biological activities of Actinidia plants, and to improve their further research, development and utilization, this review summarizes the compounds extracted from different parts of Actinidia plants since 1959 to 2020, classifies the types of constituents, reports on the pharmacological activities of relative compounds and medicinal potentials.

The review of alpha-linolenic acid: Sources, metabolism, and pharmacology

α-linolenic acid (ALA, 18:3n-3) is a carboxylic acid composed of 18 carbon atoms and three cis double bonds, and is an essential fatty acid indispensable to the human body. This study aims to systematically review related studies on the dietary sources, metabolism, and pharmacological effects of ALA. Information on ALA was collected from the internet database PubMed, Elsevier, ResearchGate, Web of Science, Wiley Online Library, and Europe PMC using a combination of keywords including "pharmacology," "metabolism," "sources." The following findings are mainly contained. (a) ALA can only be ingested from food and then converted into eicosapentaenoic acid and docosahexaenoic acid in the body. (b) This conversion process is relatively limited and affected by many factors such as dose, gender, and disease. (c) Pharmacological research shows that ALA has the anti-metabolic syndrome, anticancer, antiinflammatory, anti-oxidant, anti-obesity, neuroprotection, and regulation of the intestinal flora properties. (d) There are the most studies that prove ALA has anti-metabolic syndrome effects, including experimental studies and clinical trials. (e) The therapeutic effect of ALA will be affected by the dosage. In short, ALA is expected to treat many diseases, but further high quality studies are needed to firmly establish the clinical efficacy of ALA.

Anti-inflammatory effect of Perilla frutescens seed oil rich in omega-3 fatty acid on dextran sodium sulfate-induced colitis in mice

Background and purpose

Ulcerative colitis is a chronic inflammatory bowel disease that involves diffused inflammation of the large intestine. Omega-3 fatty acid (FA) has been known to regulate the inflammatory response associated with ulcerative colitis pathogenesis. Perilla frutescens is a valuable source of omega-3 FA and α-linolenic acid (ALA) contained in its seed oil. Therefore, the aim of this study was to evaluate the anti-inflammatory effect of Perilla seed oil (PSO) on colitis induced by dextran sulfate sodium (DSS) in a mouse model.

Experimental approach

PSO was extracted using a cold-pressed extractor and FA composition of PSO was analyzed by GC-MS. Acute colitis in mice was induced with 3% DSS in drinking water for 7 days. Some mice were treated with PSO (20, 100, 200 mg/kg BW) for 3 weeks before the DSS administration. Sulfasalazine was used as a positive control. The clinical features, histopathologic, serum, and gene expression of proinflammatory cytokines in the colon were assessed.

Finding/Results

PSO contained the highest proportion of ALA (61.51%). Furthermore, PSO pretreatment evidently reduced body weight loss, diminished diarrhea, gross bleeding, and DSS-induced colon shortening. PSO pretreatment attenuated histopathological changes in response to DSS-induced colitis. PSO pretreatment also markedly decreased inflammatory response in serum and the colon tissue of DSS-induced mice.

Conclusion and implication

ALA in PSO is suggested to be mainly responsible for the reduction of DSS-induced colitis through suppressing inflammatory markers. PSO could be further developed as a functional health supplement, which would be beneficial for anti-inflammation in the colonic mucosa.

Bioactive Lipids and Their Derivatives in Biomedical Applications

Lipids, which along with carbohydrates and proteins are among the most important nutrients for the living organism, have a variety of biological functions that can be applied widely in biomedicine. A fatty acid, the most fundamental biological lipid, may be classified by length of its aliphatic chain, and the short-, medium-, and long-chain fatty acids and each have distinct biological activities with therapeutic relevance. For example, short-chain fatty acids have immune regulatory activities and could be useful against autoimmune disease; medium-chain fatty acids generate ketogenic metabolites and may be used to control seizure; and some metabolites oxidized from long-chain fatty acids could be used to treat metabolic disorders. Glycerolipids play important roles in pathological environments, such as those of cancers or metabolic disorders, and thus are regarded as a potential therapeutic target. Phospholipids represent the main building unit of the plasma membrane of cells, and play key roles in cellular signaling. Due to their physical properties, glycerophospholipids are frequently used as pharmaceutical ingredients, in addition to being potential novel drug targets for treating disease. Sphingolipids, which comprise another component of the plasma membrane, have their own distinct biological functions and have been investigated in nanotechnological applications such as drug delivery systems. Saccharolipids, which are derived from bacteria, have endotoxin effects that stimulate the immune system. Chemically modified saccharolipids might be useful for cancer immunotherapy or as vaccine adjuvants. This review will address the important biological function of several key lipids and offer critical insights into their potential therapeutic applications.