Acetate Levels Research Articles

5-aminosalicylic acid alleviates colitis and protects intestinal barrier function by modulating gut microbiota in mice.

5-aminosalicylic acid (5-ASA) is widely used in the treatment of ulcerative colitis (UC), but its anti-inflammatory mechanism is complex and has not been fully understood. DSS model was used to test the effect of 5-ASA. Tight junction and Ki-67 were detected by western blot, immunofluorescence, and immunohistochemistry or qPCR. 16S rRNA gene sequencing of gut microbiota and subsequent bioinformatics and statistical analysis were performed to identify the specific bacteria which were associated with the treatment effect of 5-ASA. GC-MS was performed to test short-chain fatty acids (SCFAs). Antibiotic-treated mice were used to demonstrate the key role of endogenous gut microbiota. Here, we found that 5-ASA alleviated dextran sulfate sodium (DSS)-induced colitis in mice. Moreover, 5-ASA significantly repaired the intestinal barrier. At the molecular level, 5-ASA markedly raised the expression of tight junction proteins including JAM-A and occludin and cell proliferation marker Ki-67 in mice. In addition, bacterial 16S rRNA gene sequencing and bioinformatics analysis showed that 5-ASA significantly modulated the DSS-induced gut bacterial dysbiosis. In detail, it stimulated the growth of protective bacteria belonging to Faecalibaculum and Dubosiella, which were negatively correlated with colitis parameters, and blocked the expansion of pro-inflammatory bacteria such as Escherichia-Shigella and Oscillibacter, which were positively correlated with colitis in mice. Meanwhile, 5-ASA increased the cecal acetate level. Most notably, 5-ASA was no longer able to treat colitis and reverse gut barrier dysfunction in antibiotic-treated mice that lacked endogenous gut microbiota. Our data suggested that the anti-inflammatory activity of 5-ASA required the inherent intestinal flora, and the gut microbiota was a potential and effective target for the treatment of ulcerative colitis.

Lycium barbarum arabinogalactan inhibits Escherichia coli and improves Lactobacillus plantarum growth in a defined microbial model of human gut microbiome

Arabinogalactan from Lycium barbarum (LBP-3) is the major biological activity component and contributes to maintaining intestinal immune homeostasis by targeting gut microbiota and their metabolites. However, it is still a big challenge to know the specific ecological microbe-metabolite interaction regulated by LBP-3 due to the host complex diet webs and lots of unidentified intestinal bacteria. Therefore, the present study constructed a defined microbial consortium, composing of symbiotic Bacteroides caccae, Phocaeicola vulgatus, B. thetaiotaomicron, B. uniformis, B. ovatus, Lactobacillus plantarum and Escherichia coli in vitro, to investigate the impact of LBP-3 on the interactions of species and their metabolites. The utilization of LBP-3 by the defined microbial consortium of 7 intestinal species was 22.5%. Full-length 16S rRNA analysis demonstrated that LBP-3 significantly modulated the composition of synthetic bacterial community, especially inhibiting the level of opportunistic pathogenic E. coli and improving the relative abundance of probiotic L. plantarum and all Bacteroidetes species except B. ovatus. LBP-3 remarkedly influenced 27 differential metabolites, mainly belong to amino acids, peptides and analogues (37.04%) and carboxylic acid and derivatives (7.41%). Moreover, targeted metabolomics revealed that the levels of acetate, propionate, tryptophan and 5-methylthioadenosine were improved by LBP-3. In addition, LBP-3 modulated the pathways of tryptophan metabolism, cysteine and methionine metabolism, and biosynthesis of siderophore group nonribosomal peptides. Notably, some amino acids (e.g., proline and glutamate) and their related metabolic pathways (e.g., arginine and proline metabolism) altered by LBP-3 were significantly correlated with the levels of species, such as B. uniformis, P. vulgatus, and B. thetaiotaomicron.

Dried Fruit, Acetate, and Asthma: A Mediation Mendelian Randomization Analysis

Background Asthma is a common chronic condition with increasing prevalence. Diet, including dried fruit consumption, has been linked to asthma risk, but the mechanisms remain unclear. This study investigates how dried fruit consumption affects asthma risk, focusing on acetate as a potential mediator. Methods We used Mendelian Randomization (MR) to analyze the relationships between dried fruit intake, acetate levels, and asthma. We applied three MR methods—Inverse-Variance Weighted (IVW), Weighted Median (WM), and MR-Egger—to determine causal effects. Results Dried fruit intake was inversely associated with asthma risk (IVW: β=-0.506, p = 0.0135) and positively associated with acetate levels (IVW: β = 0.269, p < 0.0001). Higher acetate levels were also linked to lower asthma risk (IVW: β=-0.361, p < 0.0001). Mediation analysis showed that acetate mediates approximately 19.22% of the effect of dried fruit on asthma risk. Conclusion Dried fruit consumption reduces asthma risk, partly through increasing acetate levels. This acetate-mediated pathway accounts for about 20% of the effect, suggesting potential for dietary strategies in asthma prevention and management. Further research could enhance the understanding and applicability of these findings.

Comprehensive assessment of fragrance profiles in peony flowers through HS-GC-IMS and metabolic pathway analysis

This study addresses the identification and comparison of volatile organic compounds (VOCs) in different peony varieties to elucidate their distinct aroma profiles and the common VOCs that constitute the unique fragrance of peony flowers, laying a foundation for breeding high-quality peony varieties and developing related products. Headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) was employed to analyze and differentiate the VOCs of eight peony varieties: TAOXI, ZIHELIAN, BAITIANE, YAOHUANG, DAFUGUI, DAOJIN, HONGXIUQIU, and MANAOPAN. The study identified 87 VOCs, revealing significant differences in VOC compositions among the samples. Notably, BAITIANE displayed distinct differences in both color and VOC composition compared to the other seven varieties. It exhibited uniquely high levels of butanoic acid-M, butanoic acid-D, hexanal-D, ethanol-D, and ethyl acetate. Twelve key differential VOCs were identified as having significant impacts: ethanol-D, hexanal-D, (e)-2-hexenal-D, (e)-2-hexenal-M, hexanal-M, butanoic acid-M, acetic acid-D, acetic acid-M, butanoic acid-D, ethyl acetate, thiophene, and dimethyl sulfide. KEGG pathway analysis highlighted the roles of xenobiotics biodegradation, terpenoid metabolism, and amino acid metabolism in VOC biosynthesis. The findings are significant for the breeding of fragrant peony varieties and the development of floral-based products. The findings provide theoretical support for breeding new horticultural flower varieties and developing commercial peony products, enhancing the understanding of floral scent chemistry, and offering valuable information for the perfumery, floral food processing, and related industries.

Regulatory‐based classification of rums: a chemometric and machine learning analysis

SummaryThe Industria Licorera de Caldas (ILC) stands as a major liquor factory in Colombia, specialising in the production of various rum types including Tradicional, Juan de la Cruz, Carta de Oro, and Reserva Especial. These rums, as congeneric drinks, are known for their rich content of volatile compounds that define their sensory characteristics. To be commercialised, each rum batch must comply with Colombian standard NTC278 which defines rigorous assessment of congener content and various physicochemical parameters. Thus, the ILC has accumulated a vast amount of data over the years. This study conducts a comprehensive analysis of ILC rums, using chemometric techniques and machine‐learning classification models such as PCA, KNN, LDA, and RF. The aim was to distinguish between rum types based on parameters specified for standard compliance, streamlining the process without the need for additional or extensive new methodologies. As a result, through PCA data exploration, it was revealed that acetaldehyde, ethyl acetate, and isobutanol levels are instrumental in differentiating rum variants. Similarly, all classification models achieved accuracy levels exceeding 0.83 and precision surpassing 0.93. These findings pave the way for further research in the development of an ILC‐specific sensor for rapid and reliable liquor authenticity testing.

An Automated Sprinkler Cooling System Effectively Alleviates Heat Stress in Dairy Cows.

(1) Background: Heat stress detrimentally restricted economic growth in dairy production. In particular, the cooling mechanism of the spraying system effectively reduced both environmental and shell temperatures. This study was designed to investigate the underlying modulatory mechanism of an automatic cooling system in alleviating heat-stressed dairy cows. (2) Methods: A total of 1208 multiparous dairy cows was randomly allocated into six barns, three of which were equipped with automatic sprinklers (SPs), while the other three were considered the controls (CONs). Each barn was considered a replicate. (3) Results: Body temperatures and milk somatic cell counts significantly decreased, while DMI, milk yield, and milk fat content significantly increased under SP treatment. Rumen fermentability was enhanced, embodied by the increased levels of total VFA, acetate, propionate, and butyrate after SP treatment. The rumen microbiota results showed the relative abundances of fiber-degrading bacteria, including the Fibrobacters, Saccharofermentans, Lachnospira, Pseudobutyrivibrio, Selenomonas, and Succinivibrio, which significantly increased after receiving the SP treatment. (4) Conclusions: This study demonstrated that SP effectively alleviated heat stress and improved production performances and milk quality through modulating the rumen microbiota composition and fermentation function of dairy cows.

Integrated Analysis of Metabolomics, Flavoromics, and Transcriptomics for Evaluating New Varieties of Amomum villosum Lour.

Amomum villosum Lour. (A. villosum) is the original plant of the medicinal and culinary spice Amomi Fructus (Sharen) and is an important economic crop in the Lingnan region of China. During the cultivation and production of A. villosum, prolonged reliance on single asexual reproduction has exacerbated the degradation of its varieties, leading to inconsistent yields and quality. Building upon earlier cultivar selection efforts, this study provides a comprehensive evaluation of two newly bred A. villosum varieties (A11 and A12) from perspectives including plant traits, product characteristics, active ingredients, and multi-omics analysis. It was found that A12 plants display enhanced robustness, more aromatic fruits, higher yields, and elevated levels of bornyl acetate, A11 shows the advantage of a high camphor content, and the different metabolites and differentially expressed genes of the two varieties were significantly enriched in multiple metabolic pathways. Additionally, A12 contained more terpenoids and substances with aromatic odors such as sweet, fruity, floral, and green. Furthermore, a key gene (Wv_032842) regulating the acetylation of bornyl was discovered, and its significantly higher expression, in A12. In conclusion, this study has a guiding significance for the evaluation of germplasm resources and the breeding of excellent varieties of A. villosum.

Propyl acetate protects intestinal barrier during parenteral nutrition in mice and Caco-2 cells.

Gut microbiota dysbiosis induces intestinal barrier damage during parenteral nutrition (PN). However, the underlying mechanisms remain unclear. This study aimed to investigate gut microbiota dysbiosis, luminal short-chain fatty acids, and autophagy in a mouse model and how these short-chain fatty acids regulate autophagy. Eight-week-old male specific-pathogen-free mice were randomly divided into a Chow group (standard diet and intravenous normal saline infusion) and a PN group (continuous infusion of PN nutrient solution) for 7 days. Caco-2 cells were also treated with intestinal rinse solutions from Chow and PN mouse models. Compared with the Chow group, the PN group exhibited increased Proteobacteria and decreased Firmicutes, correlating with decreased propyl acetate. In the PN group, intestinal tissue exhibited elevated adenosine monophosphate-activated protein kinase (AMPK) phosphorylation, LC3II protein levels, and Atg3 and Atg7 messenger RNA levels. P62 protein levels were decreased, indicating an increase of autophagy flux in the PN group. In the Caco-2 cell model, cells treated with PN solution plus propyl acetate exhibited increased Claudin-1 and occluding along with decreased interleukin-6 and tumor necrosis factor α compared with those treated with PN solution alone. Propyl acetate addition inhibited the AMPK-mammalian target of rapamycin (mTOR) pathway, mitigating the excessive autophagy induced by the PN intestinal rinse solution in Caco-2 cells. PN led to a significant reduction in propyl acetate levels in the intestine, excessive activation of autophagy, and barrier dysfunction. Propyl acetate inhibited excessive autophagy via the AMPK/mTOR signaling pathway and protected the intestinal barrier during PN.

Response of anammox to organics with different degradation characteristics and exposure time: Performance, sludge characteristics and bacterial community

The effects of typical organic compounds including easily degradable organic matters sodium acetate, yeast and methanol, and refractory organic matter (ROM) humic acid on anaerobic ammonium oxidation (anammox) systems in short-term and medium-term exposure time were studied. During short-term experiments, nitrogen removal activity (NRA) was inhibited at sodium acetate level of 150 mg L−1 total organic carbon (TOC) and methanol level of 30–150 mg L−1 TOC, but humic acid and yeast (≤150 mg L−1 TOC) enhanced nitrogen removal in anammox systems. The greatest NRA of 30.10 mg TN g−1 VSS h−1 was recorded at yeast level of 90 mg L−1 TOC. In medium-term experiments, organics significantly inhibited the nitrogen removal ability. As a ROM, humic acid enhanced sludge aggregation and biological diversity, but decreased the bioactivity and extracellular polymeric substances levels. Due to the endogenous denitrification, the relative abundance of anammox bacteria (AnAOB) was decreased. Candidatus Kuenenia is still dominant in sludge with methanol and humid acid, but AnAOB are not dominant due to the addition of sodium acetate and yeast. This research would be beneficial for the full-scale application of the anammox process in treating real wastewater with organics and ammonia.

Acetate enables metabolic fitness and cognitive performance during sleep disruption

Sleep is essential for overall health, and its disruption is linked to increased risks of metabolic, cognitive, and cardiovascular dysfunctions; however, the molecular mechanisms remain poorly understood. This study investigated how sleep disturbances contribute to metabolic imbalance and cognition impairment using a chronic sleep fragmentation (SF) mouse model. SF mice exhibited impaired cognition, glucose metabolism, and insulin sensitivity compared with controls. We identified increased acetate levels in hypothalamic astrocytes as a defensive response in SF mice. Through acetate infusion or astrocyte-specific Acss1 deletion to elevate acetate levels, we observed mitigated metabolic and cognitive impairments in SF mice. Mechanistically, acetate binds and activates pyruvate carboxylase, thereby restoring glycolysis and the tricarboxylic acid cycle. Among individuals most commonly affected by SF, patients with obstructive sleep apnea exhibited elevated acetate levels when coupled with type 2 diabetes. Our study uncovers the protective effect of acetate against sleep-induced metabolic and cognitive impairments.

Metabolic Profiles of the Gut Microbiota in Patients with Different Stages of Metabolism Dysfunction-Associated Fatty Liver Disease

Aim: to study the metabolic activity of the intestinal microbiota depending on the stage of metabolic dysfunction-associated fatty liver disease (MAFLD). Materials and methods. The study included 85 patients with MAFLD (27 patients with steatosis without steatohepatitis and fibrosis, 42 patients with steatohepatitis, 16 patients with cirrhosis as an outcome of MAFLD, Child — Pugh class A–B) and 20 healthy people who formed the control group. The level and spectrum of short-chain fatty acids (SCFA) were determined by gas-liquid chromatography. Results. It was found that patients with MAFLD at the stage of steatosis and cirrhosis of the liver have unidirectional changes in the metabolic activity of the intestinal microbiota. We established a decrease in the absolute concentrations of SCFA — their total content, the level of acetate, propionate, butyrate, a decrease in the level of isoacids. The SCFA profiles showed an increase in the proportion of acetate and a decrease in propionate and butyrate. Moreover, changes in the named parameters of SCFAs are aggravated with progression to liver cirrhosis. At the stage of steatohepatitis, we identified two subgroups of patients with different levels of metabolic activity of the microbiota. Patients whose microbiota metabolism for SCFA production was high had correspondingly elevated SCFA levels. And, on the contrary, patients in whom the metabolic activity of the microbiota was reduced were characterized by a steady decrease in SCFAs and disease progression to liver cirrhosis. In the study, we showed an inverse correlation between the calculated prognostic indices of NFS and FIB-4, elastography values with the total level of SCFA, the level of acetate, propionate, butyrate. Thus, a decrease in the content of SCFA for patients with MAFLD can be considered as a prognostic marker of an unfavorable course of liver disease.

High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy of Paired Clinical Liver Tissue Samples from Hepatocellular Cancer and Surrounding Region.

The global burden of liver cancer is increasing. Timely diagnosis is important for optimising the limited available treatment options. Understanding the metabolic consequences of hepatocellular carcinoma (HCC) may lead to more effective treatment options. We aimed to document metabolite differences between HCC and matched surrounding tissues of varying aetiology, obtained at the time of liver resection, and to interpret metabolite changes with clinical findings. High-resolution magic angle spinning nuclear magnetic resonance (HRMAS-NMR) spectroscopy analyses of N = 10 paired HCC and surrounding non-tumour liver tissue samples were undertaken. There were marked HRMAS-NMR differences in lipid levels in HCC tissue compared to matched surrounding tissue and more subtle changes in low-molecular-weight metabolites, particularly when adjusting for patient-specific variability. Differences in lipid-CH3, lipid-CH2, formate, and acetate levels were of particular interest. The obvious differences in lipid content highlight the intricate interplay between metabolic adaptations and cancer cell survival in the complex microenvironment of liver cancer. Differences in formate and acetate might relate to bacterial metabolites. Therefore, documentation of metabolites in HCC tissue according to histology findings in patients is of interest for personalised medicine approaches and for tailoring targeted treatment strategies.

Imperata cylindrica polysaccharide ameliorates intestinal dysbiosis and damage in hyperuricemic nephropathy

In this study, a combination of adenine and potassium oxonate was utilized to establish a hyperuricemic nephropathy (HN) mouse model, aiming to elucidate the effect through which Imperata Cylindrica polysaccharide (ICPC-a) ameliorates HN. In HN mice, an elevation in the abundance of Erysipelatoclostridium, Enterococcus, Prevotella, and Escherichia-Shigella was observed, whereas Lactobacillus and Bifidobacterium declined. Additionally, the systemic reductions in the levels of acetate, propionate, and butyrate, along with a significant increase in indole content, were noted. HN mice demonstrated intestinal barrier impairment, as evidenced by diminished mRNA expression of ZO-1, Occludin, and Claudin-1 and increased Mmp-9 levels. The pro-inflammatory factors IL-6, IL-17, TNF-α, IFN-γ, and COX-2 were overexpressed. Subsequent gavage intervention with ICPC-a markedly mitigated the inflammatory response and ameliorated colon tissue damage. ICPC-a effectively regulated the abundance of gut microbiota and their metabolites, including short-chain fatty acids (SCFAs), bile acids (BAs), and indole, promoting the correction of metabolic and gut microbiota imbalances in HN mice. These findings underscored the capacity of ICPC-a as a prebiotic to modulate gut microbiota and microbial metabolites, thereby exerting a multi-pathway and multi-targeted therapeutic effect on HN.

Characteristics of stachyose-induced effects on gut microbiota and microbial metabolites in vitro associated with obesity in children.

Childhood obesity presents a serious health concern associated with gut microbiota alterations. Dietary interventions targeting the gut microbiota have emerged as promising strategies for managing obesity in children. This study aimed to elucidate the impact of stachyose (STS) supplementation on the gut microbiota composition and metabolic processes in obese children. Fecal samples were collected from 40 obese children (20 boys and 20 girls) aged between 6 and 15 and in vitro fermentation was conducted with or without the addition of STS, respectively, followed by 16S rRNA amplicon sequencing and analysis of short-chain fatty acids (SCFAs) and gases. Notably, our results revealed that STS supplementation led to significant alterations in gut microbiota composition, including an increase in the abundance of beneficial bacteria such as Bifidobacterium and Faecalibacterium, and a decrease in harmful bacteria including Escherichia-Shigella, Parabacteroides, Eggerthella, and Flavonifractor. Moreover, STS supplementation resulted in changes in SCFAs production, with significant increases in acetate levels and reductions in propionate and propionate, while simultaneously reducing the generation of gases such as H2S, H2, and NH3. The Area Under the Curve (AUC)-Random Forest algorithm and PICRUSt 2 were employed to identify valuable biomarkers and predict associations between the gut microbiota, metabolites, and metabolic pathways. The results not only contribute to the elucidation of STS's modulatory effects on gut microbiota but also underscore its potential in shaping metabolic activities within the gastrointestinal environment. Furthermore, our study underscores the significance of personalized nutrition interventions, particularly utilizing STS supplementation, in the management of childhood obesity through targeted modulation of gut microbial ecology and metabolic function.

Metabolomic and transcriptomic integration reveals the mechanism of aroma formation as strawberries naturally turn colors while ripening

Aroma is an important indicator of fruit flavor, but mechanisms of aroma formation in strawberries (Fragaria spp.) during natural ripening are still not clear. In this study, aroma compounds in strawberry cultivars were analyzed using gas chromatography–mass spectrometry (GC–MS). Richly creamy strawberry cultivars in particular expressed high levels of vanillin acetate and coumarin (up-regulated by 12.6- and 9.8-fold, respectively), while the aroma-free cultivars were dominated by differential changes in terpenes and alcohols. Further research using liquid chromatography-mass spectrometry (LC-MS) and RNA-Seq indicated that the activation of the phenylpropanoid biosynthesis and alpha-linolenic acid metabolic pathways constituted the key to formation of aroma compounds in creamy strawberry cultivars. The results of this study not only provide a well-defined database to detect aroma compounds in different strawberry cultivars but also explore the underlying mechanisms of creamy aroma formation in strawberries.

Fermentation Performances and Aroma Contributions of Selected Non-Saccharomyces Yeasts for Cherry Wine Production.

This study evaluates the fermentation performances of non-Saccharomyces strains in fermenting cherry must from Italian cherries unsuitable for selling and not intended to be consumed fresh, and their effects on the chemical composition of the resulting wine. Fermentation trials in 100 and 500 mL of must were carried out to select 21 strains belonging to 11 non-Saccharomyces species. Cherry wines obtained by six select strains were chemically analyzed for fixed and volatile compounds. Quantitative data were statistically analyzed by agglomerative hierarchical clustering, partial least squared discriminant analysis, and principal component analysis. Wines revealed significant differences in their composition. Lactic acid and phenylethyl acetate levels were very high in wines produced by Lachancea and Hanseniaspora, respectively. Compared to S. cerevisiae wine, non-Saccharomyces wines had a lower content of fatty acid ethyl esters 4-vinyl guaiacol and 4-vinyl phenol. The multivariate analysis discriminated between wines, demonstrating the different contributions of each strain to aroma components. Specifically, all wines from non-Saccharomyces strains were kept strictly separate from the control wine. This study provided comprehensive characterization traits for non-conventional strains that enhance the aroma complexity of cherry-based wine. The use of these yeasts in cherry wine production appears promising. Further investigation is required to ascertain their suitability for larger-scale fermentation.

Characteristics and Functions of Dominant Yeasts Together with Their Applications during Strong-Flavor Baijiu Brewing.

Yeasts are pivotal brewing microbes that are associated with the flavor and quality of Chinese baijiu, yet research on dominant yeasts in strong-flavor baijiu brewing remains limited. In this study, Saccharomyces cerevisiae, Pichia kudriavzevii, and Kazachstania bulderi were identified as predominated yeasts in strong-flavor baijiu. Each strain showed distinct characteristics in ethanol resistance, thermal tolerance, and lactic acid tolerance, severally. S. cerevisiae FJ1-2 excelled in ethanol and ethyl ester production, P. kudriavzevii FJ1-1 in ethyl acetate, and K. bulderi FJ1-3 in lactic acid generation. Subsequently, the reinforced Fuqu of each yeast were severally prepared for application in baijiu brewing to verify their functions. Results revealed that the relative abundance of fortified yeast in each group rose. Pichia, Kazachstania, and Saccharomyces emerged as the core microbe for each group, respectively, by co-occurrence network analysis, influencing the microbiota to regulate flavor substances. In short, P. kudriavzevii FJ1-1 enhanced ethyl acetate. K. bulderi FJ1-3 improved ethyl caproate production and decreased levels of ethyl acetate and higher alcohols by modulating yeast community between Pichia and Saccharomyces. This is a systematic endeavor to study the functions of yeasts of strong-flavor baijiu, providing a solid basis for improving baijiu quality.

NMR-Based Metabolomics of Blood Serum in Predicting Response to Induction Chemotherapy in Head and Neck Cancer-A Preliminary Approach.

The role of induction chemotherapy (iCHT) in locally advanced head and neck squamous cell carcinoma (LA-HNSCC) is still to be established due to high toxicity and variable response rates. The aim of this retrospective study is to use NMR-based serum metabolomics to predict the response rates to iCHT from the pretreatment samples. The studied group consisted of 46 LA-HNSCC patients treated with iCHT. The response to the treatment was evaluated by the clinical, fiberoptic, and radiological examinations made before and after iCHT. The proton nuclear magnetic resonance (1H NMR) serum spectra of the samples collected before iCHT were acquired with a 400 MHz spectrometer and were analyzed using multivariate and univariate statistical methods. A significant multivariate model was obtained only for the male patients. The treatment-responsive men with >75% primary tumor regression after iCHT showed pretreatment elevated levels of isoleucine, alanine, glycine, tyrosine, N-acetylcysteine, and the lipid compounds, as well as decreased levels of acetate, glutamate, formate, and ketone bodies compared to those who did not respond (regression of the primary tumor <75%). The results indicate that the nutritional status, capacity of the immune system, and the efficiency of metabolism related to protein synthesis may be prognostic factors for the response to induction chemotherapy in male HNSCC patients. However, larger studies are required that would validate the findings and could contribute to the development of more personalized treatment protocols for HNSCC patients.

Supplementation of yeast culture to low-fishmeal diets improves growth, intestinal health, and heat stress resistance in juvenile Chinese mitten crab (Eriocheir sinensis)

Yeast culture (YC), a microecological product derived from yeast fermentation, can enhance animal growth, health, and resistance to heat stress. However, its impact on the economically significant crustacean Eriocheir sinensis has not been demonstrated. This study investigated the effects of low-fishmeal YC on the growth, intestinal health, and heat stress resistance of juvenile Chinese mitten crabs. Crabs (0.72 ± 0.01 g) were distributed across 42 tanks, and 40 crabs were randomly maintained per tank in six replicates. The crabs were fed a control diet (35% fish meal) or six YC concentrations (15% fish meal; 0, 0.8, 1.6, 2.4, 3.2, or 4.0 g/kg) for 56 days. After sample collection, the remaining crabs were subjected to a 72-h heat stress challenge at 32 °C. A moderate-yield YC diet significantly improved weight gain, specific growth rate, and digestive enzyme activities (α-amylase, trypsin, and lipase) compared to those of crabs fed a 15% fishmeal diet without YC. Notably, the diet with 3.2 g/kg YC supplementation was performed as well as crabs fed a 35% fishmeal diet. YC also enhanced intestinal morphology in the low-fishmeal diet group and reduced oxidative damage by increasing the expression of genes related to the peritrophic membrane and tight junction proteins. Furthermore, YC supplementation diversified the intestinal microbiota, significantly increased the abundance of Firmicutes and the genus Shewanella, increased acetate and butyrate levels and decreased the abundance of Proteobacteria. Correlation analysis revealed that weight gain and specific growth rate were associated with most digestive activity and intestinal health indicators. Following heat stress challenge, YC protected against oxidative stress and enhanced serum immunity at elevated temperatures. This study indicated that incorporating YC in low-fishmeal diets significantly increases juvenile crab growth, improves intestinal health, and mitigates oxidative stress induced by temperature elevation. The optimal YC concentration was determined to be 2.71 g/kg through regression analysis.

Chitosan alleviates symptoms of Parkinson's disease by reducing acetate levels, which decreases inflammation and promotes repair of the intestinal barrier and blood-brain barrier.

Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse model of Parkinson's disease and found that it effectively reduced dopamine neuron injury, neurotransmitter dopamine release, and motor symptoms. These neuroprotective effects of chitosan were related to bacterial metabolites, specifically short-chain fatty acids, and chitosan administration altered intestinal microbial diversity and decreased short-chain fatty acid production in the gut. Furthermore, chitosan effectively reduced damage to the intestinal barrier and the blood-brain barrier. Finally, we demonstrated that chitosan improved intestinal barrier function and alleviated inflammation in both the peripheral nervous system and the central nervous system by reducing acetate levels. Based on these findings, we suggest a molecular mechanism by which chitosan decreases inflammation through reducing acetate levels and repairing the intestinal and blood-brain barriers, thereby alleviating symptoms of Parkinson's disease.