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Bacteroides cellulosilyticus-derived 2-hydroxyphenylacetic acid rectifies hepatic lipid homeostasis in MASLD by targeting the PPARγ-CD36 axis.

The gut microbiota plays an important role in the occurrence and development of metabolic dysfunction-associated steatotic liver disease (MASLD), but the specific molecular mechanisms involved have not been fully elucidated. In this study, human cohort studies were performed to identify that the relative abundance of Bacteroides cellulosilyticus (B. cellulosilyticus) was significantly decreased in patients with MASLD. Through the integration of metagenomic and metabolomic analyses, it was confirmed that B. cellulosilyticus and its metabolite 2-hydroxyphenylacetic acid (2HPAA) are key factors regulating the occurrence and development of MASLD. Single-cell sequencing and lipidomic analyses revealed that 2HPAA can enter the liver through the enterohepatic circulation to exert regulatory effects. Specifically, 2HPAA inhibits the peroxisome proliferator-activated receptor γ (PPARγ) signaling pathway, thereby suppressing the expression of the fatty acid transporter CD36. Meanwhile, 2HPAA regulates lipid metabolism in hepatocytes by significantly enhancing palmitate conversion efficiency and inhibiting CD36 palmitoylation. This dual regulatory effect on CD36 expression and palmitoylation can reduce lipid accumulation in hepatocytes and ultimately alleviate MASLD progression. These findings reveal the mechanism by which B. cellulosilyticus and 2HPAA alleviate MASLD by targeting the PPARγ-CD36 pathway. This work provides a new perspective for the study of gut microbiota-host interactions in regulating liver diseases.

PPAR gamma

Acetic acid-induced translational repression involves eIF2B body formation and Ded1 sequestration into stress granules in yeast.

Elucidating the physiological impact of acetic acid stress and the corresponding yeast responses is essential for advancing fundamental biology and improving industrial alcoholic fermentation. Despite numerous genome-wide studies, information on the effects of acetic acid stress on yeast translational regulation remains limited. We found that a sublethal concentration of acetic acid (35 mM, 0.2% v/v) causes translational repression, accompanied by the formation of eIF2B bodies and the phosphorylation of eIF2α, both of which are involved in the regulation of translation initiation. Acetic acid also caused the sequestration of Ded1, a DEAD-box RNA helicase crucial for translation initiation, into stress granules. Removal of acetic acid restored translational activity and the proper localization of eIF2B and Ded1, indicating the reversibility of acetic acid-induced translational repression. Furthermore, when yeast cells were pretreated with 0.05% acetic acid, translational repression under subsequent 0.2% acetic acid stress was attenuated in wild-type cells but not in hrk1Δ cells. This indicates that Hrk1, a Pma1 activator, is required to sufficiently enhance tolerance to acetic acid-induced translational repression. These findings provide novel insights into the physiological effects of acetic acid stress on translational activity and translation-related factors in yeast cells.

Saccharomyces cerevisiae

Effect of a 6-month low-carbohydrate diet on the circulating fatty acid composition in patients with type 2 diabetes: a secondary analysis of an open-label randomized controlled trial.

BACKGROUND: Circulating fatty acid profiles are linked to cardiovascular disease risk and mortality. Short-term interventions suggest that low-carbohydrate diets (LCDs) promote cardioprotective shifts in circulating fatty acids in obesity. OBJECTIVES: We examined whether a 6-mo, non-calorie-restricted, LCD high in fat similarly improves circulating fatty acid composition in adults with type 2 diabetes. METHODS: In an open-label, randomized, controlled trial, 71 individuals with type 2 diabetes were randomly assigned 2:1 to an LCD [maximum of 20 E% (energy per cent) carbohydrates] or a control diet (50-60 E% carbohydrates) for 6 mo with no restriction in energy intake. The prespecified secondary outcomes were the mean difference in change between groups in serum phospholipid fatty acids in weight percentage (wt%) measured by gas chromatography and reported as 95% confidence intervals (CIs) and significance adjusted for multiple comparisons (q value). RESULTS: LCD reduced total saturated [-0.6 (CI: -0.9, -0.2)] and monounsaturated fatty acids [-0.9 (CI: -1.4, -0.3)] and increased total polyunsaturated fatty acids [1.3 (CI: 0.6, 2.0)] compared with the control diet (all q < 0.05). Importantly, LCD reduced palmitoleic acid (16:1n-7) [-0.13 (CI: -0.21, -0.06)], a marker of de novo lipogenesis, by 23% and dihomo-&#x3b3;-linolenic acid (20:3n-6) [-0.38 (CI: -0.67, -0.09)] by 12%, whereas it increased arachidonic acid (20:4n-6) [1.1 (CI: 0.3, 2.0)] by 9% compared with the control diet (all q < 0.05). Moreover, the LCD improved estimated desaturase activities by lowering stearoyl-coenzyme A desaturase 1 [-0.5 (CI: -0.7, -0.2)] and &#x394;6 desaturase [-0.6 (CI: -0.9, -0.2)] and increasing &#x394;5 desaturase [1.05 (CI: 0.3, 1.79)] activities, respectively (all q < 0.01). These changes occurred despite a 2.6-fold higher intake of saturated fatty acids in the LCD group. CONCLUSIONS: A 6-mo, non-calorie-restricted LCD modified the circulating composition of fatty acids in adults with type 2 diabetes in a manner consistent with a potentially favorable cardioprotective profile. This trial was registered at www. CLINICALTRIALS: gov as NCT03068078.

Humans

Associations of red blood cell fatty acids with personality traits: 10-year follow-up in the Kibbutzim Family Study (KFS).

BACKGROUND: The ability of hostility and type-A personality to predict cardiovascular outcomes makes understanding antecedents of these personality traits an important public health objective. OBJECTIVES: This study aimed to examine whether blood-measured fatty acids (the exposure) are associated with hostility and type-A personality (the outcome), while accounting for lifestyle, sociodemographic factors, and polygenic background. METHODS: Personality traits, sociodemographic, and lifestyle data were obtained in 1992-1993 from 452 family members living in kibbutz settlements in Israel (visit 1) and remeasured 8 to 10 y later in 379 individuals (visit 2). Red blood cell (RBC) fatty acid concentrations were determined in visit 1 by gas chromatography. Longitudinal associations of visit 1 fatty acids with visit 2 personality traits were examined using linear models, before and after controlling for baseline personality scores. The contribution of environmental factors to personality scores beyond heritability was estimated by variance decomposition. RESULTS: In longitudinal analysis, 1% increase in visit 1 total n-6 (&#x3c9;-6) fatty acid was associated with a 0.328-unit decrease in visit 2 type-A score [95% confidence interval (CI): -0.571, -0.085]. After adjustment for baseline personality levels, the association was slightly attenuated (&#x3b2;= -0.204; CI: -0.399, -0.009). One percent higher total n-6 was also associated with 1.119 units lower visit 2 hostility score (CI: -2.777, 0.038; P = 0.055). Finally, independent of the genetic contribution (32%-38% of adjusted variability in hostility and type-A personality), 1% increase in total n-3 and total n-6 was associated with 2.539 (CI: -3.907, -1.171) and 0.201 (CI: -0.365, -0.037) units lower hostility and type-A scores, respectively. CONCLUSIONS: Higher RBC total n-6 fatty acid concentrations are associated with lower type-A personality scores. After adjustment for baseline personality levels, the associations between total n-6 and hostility and between total n-3 and hostility are attenuated. These findings support further investigation of the relationship between fatty acid biology and personality traits using study designs better suited to causal inference.

Humans

Bempedoic Acid and First and Recurrent Limb Outcomes in Statin-Intolerant Patients With Peripheral Artery Disease: Insights From the CLEAR Outcomes Trial.

BACKGROUND: Patients with peripheral artery disease (PAD) are at high risk of major adverse limb events (MALE) and major adverse cardiovascular events (MACE). Recently, bempedoic acid was shown to reduce MACE in primary and secondary prevention patients. Whether bempedoic acid reduces the risk of MALE in patients with PAD is unknown. METHODS: CLEAR Outcomes (Cholesterol Lowering via Bempedoic Acid [ETC1002], an ACL-Inhibiting Regimen) randomized 13&#x2009;970 patients to bempedoic acid 180 mg or placebo from December 22, 2016, to August 14, 2019. The trial primary end point was MACE-4, defined as death resulting from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization. A clinical history of PAD was reported by investigators at baseline. Two blinded vascular medicine specialists independently adjudicated MALE, including adverse events indicating worsening PAD symptoms leading to revascularization, chronic limb-threatening ischemia, and acute limb ischemia. Outcomes were assessed as time to first event and total (including recurrent) events with a negative binomial approach. RESULTS: A total of 1624 of the enrolled patients (mean&#xb1;SD age, 63.9&#xb1;9.9 years; 915 [56.3%] female) had PAD at baseline. In patients with PAD in the placebo group, 69 (8.3%) had MALE over a median of 40.6 months, with rate of recurrent events of 4.0%/y. Bempedoic acid reduced the risk of MALE by 36% (hazard ratio, 0.64 [95% CI, 0.44-0.93]; P=0.018). Bempedoic acid reduced total MALE by 45% (relative risk, 0.55 [95% CI, 0.35-0.85]; P=0.007). First MACE-4 or MALE was reduced overall by 13% (hazard ratio, 0.87 [95% CI, 0.80-0.95]) with consistent effects with PAD (hazard ratio, 0.82 [95% CI, 0.64-1.04]) and without PAD (hazard ratio, 0.87 [95% CI, 0.79-0.86]; Pinteraction=NS) but not statistically significant within the PAD subgroup alone. Total MACE-4 or MALE was reduced (relative risk, 0.81 [95% CI, 0.73-0.90]) overall with consistent effects in PAD (relative risk, 0.71 [95% CI, 0.54-0.95]) and without PAD (relative risk, 0.82 [95% CI, 0.73-0.92]; Pinteraction=NS). CONCLUSIONS: Patients with PAD are at high risk of MALE and MACE. Bempedoic acid reduces both MACE and MALE in patients with atherosclerotic vascular disease, with notable absolute benefits in patients with PAD. These findings support (1) the importance of lowering low-density lipoprotein cholesterol in patients with PAD to reduce overall vascular risk and (2) the benefits of bempedoic acid in this population.

Humans

Bone progression in multiple myeloma: Benefit of zoledronic acid for patients achieving at least Very Good Partial Response and prognostic value of bone turnover markers.

The Magnolia study demonstrated that continuation of zoledronic acid (ZOL) beyond 2&#x2009;years reduces the risk of progressive bone disease (PBD) in patients with multiple myeloma (MM). This follow-up study investigated the effects of ZOL in patients achieving very good partial response (VGPR) compared to patients who did not and whether bone turnover markers could identify patients at an increased risk of PBD following treatment cessation. Two Magnolia trial subgroups were analysed: patients with VGPR or better after 2&#x2009;years of ZOL, randomized to either continued treatment or observation, and patients randomized to observation in whom serial bone markers (C-terminal cross-linked telopeptide of type I collagen [CTX], procollagen type I N-terminal propeptide [P1NP], bone-specific alkaline phosphatase [BAP], tartrate-resistant acid phosphatase isoform 5b [TRAcP]) were measured for up to 4&#x2009;years. Continued monthly ZOL beyond 2&#x2009;years significantly reduced the risk of PBD (hazard ratio 0.40; 95% confidence interval [CI] 0.16-0.92) in patients with VGPR or better (subgroup 1). After ZOL discontinuation, bone markers increased gradually. Elevated CTX (&#x2265;0.30&#x2009;&#x3bc;g/L) and TRAcP (&#x2265;4&#x2009;U/L) levels were associated with increased 6-month PBD risk (29% and 15% respectively) (subgroup 2). Continuation of ZOL beyond 2&#x2009;years seems to reduce skeletal progression risk in patients achieving VGPR or better. Elevated CTX or TRAcP levels may help identify patients who could benefit from re-initiating ZOL.

Humans

Efficacy and safety of split-dose ultra-low-volume polyethylene glycol with ascorbic acid versus sodium picosulfate with magnesium citrate for bowel preparation: a systematic review and meta-analysis.

Colonoscopy remains the gold standard for early detection and prevention of colorectal cancer, with adequate bowel cleansing being pivotal for its success. This systematic review aims to evaluate the efficacy and safety of split-dose ultra-low-volume polyethylene glycol (PEG) with ascorbic acid (Asc) versus sodium picosulfate magnesium citrate for bowel preparation. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a comprehensive literature search across Embase, PubMed, Web of Science, and Scopus from inception to July 2025. Data analysis was conducted using R version 4.2.2 (31 October 2022) and RStudio version 2022.07.2 (2009-2022, RStudio, Inc.) Our literature search yielded six eligible studies involving 3285 patients. Our findings indicate no significant differences in overall and right-sided colon adequate cleansing rates between the two regimens: risk ratio: 1.05, 95% confidence interval (CI): 0.99-1.12, P &#x2005;=&#x2005;0.1082; and risk ratio: 1.03, 95% CI: 0.99-1.08, P &#x2005;=&#x2005;0.1755, respectively. However, PEG + Asc demonstrated a significantly lower rate of vomiting compared to sodium picosulfate magnesium citrate (risk ratio: 2.58, 95% CI: 0.94-2.78, P &#x2005;=&#x2005;0.0008), suggesting better tolerability. Other secondary outcomes, including nausea, abdominal pain, and overall Boston Bowel Preparation Scale scores, did not show significant differences. The quality of the evidence varied across the outcomes. Our results support the comparable efficacy of both bowel preparation agents while highlighting PEG + Asc's potential advantages in tolerability. Our findings suggest that the choice between these two preparations can be tailored to the specific patient, considering their preferences or previous experiences, although some caution is advised in interpreting these findings.

Humans

Proteomic characterization of the acquired enamel pellicle under acidic challenges at early and mature formation stages.

OBJECTIVES: This study aimed to characterize acquired enamel pellicle (AEP) proteomic changes after exposure to citric acid (CA) and hydrochloric acid (HCl) under different pellicle formation times (3 and 120&#x202f;min) in the same volunteers. DESIGN: Nine healthy volunteers participated in this randomized crossover in vivo study. The AEP was allowed to form for 3 or 120&#x202f;min and subsequently exposed for 10&#x202f;s to deionized water (control), 1% CA (pH 2.5), or 0.01&#x202f;M HCl (pH 2.0). Pellicle samples were collected, followed by protein extraction, tryptic digestion, and analysis by nanoliquid chromatography (nanoLC) coupled to mass spectrometry (MS) with MSE (data-independent acquisition; nanoLC-MS&#x1d31;). Label-free quantitative proteomics were performed for relative quantification using t-test (p&#x202f;<&#x202f;0.05). RESULTS: At 120&#x202f;min, CA exposure markedly reduced several typical AEP proteins, especially acidic proline-rich proteins (PRPs). Conversely, basic PRPs were upregulated, suggesting acid-resistance protein signature. At 3&#x202f;min, basal-layer proteins (PRPs, cystatins, histatins and mucins) were more abundant. Hemoglobins increased 6-8-fold (up to 150-fold in 3&#x202f;min control), suggesting association with early pellicle formation and an acid-resistant protein signature. CA exposures for 120&#x202f;min also upregulated typical AEP proteins (PRPs, mucins, cystatins, immunoglobulins), while HCl exposure depleted albumins and lactotransferrin. CONCLUSION: Intrinsic and extrinsic acids induce distinct proteomic signatures in the AEP. Hemoglobin and PRPs appear consistently enriched in the early pellicle layer, reflecting an initial acid-resistant protein signature. These findings provide new insights into the molecular remodeling of the AEP following intrinsic and extrinsic acid exposure, highlighting proteins potentially involved in early-stage pellicle formation.

Humans

Prophylactic folinic acid prevents pemetrexed myelosuppression: A randomized trial toward safer treatment with chemotherapy in non-small cell lung cancer.

Background Pemetrexed is a cornerstone in advanced non-small cell lung cancer treatment. Although generally well tolerated, severe myelosuppression occurs in 26% of patients. Preventing chemotherapy-associated toxicity has become increasingly important with the introduction of osimertinib combined with pemetrexed-based chemotherapy. Due to substantial toxicity, this regimen is often not administered to frail patients. Folinic acid prophylaxis can mitigate pemetrexed-induced toxicity, however its preventive use has not been routinely studied. We aimed to investigate the efficacy of folinic acid prophylaxis to reduce myelosuppression. Methods Fifty patients treated with pemetrexed were randomized (1:1) to receive pemetrexed with or without oral folinic acid prophylaxis on days 2-4 after each chemotherapy cycle. The primary endpoint was absolute neutrophil count (ANC) after the first chemotherapy cycle. Secondary endpoints included ANC after the second cycle, grade neutropenia, treatment efficacy, renal function and incidence of dose modifications. Results Twenty-four patients received folinic acid and twenty-six served as controls. Higher ANC were observed in the folinic acid group after the first cycle (median 3.79; IQR 2.22-4.93 vs. 1.85; IQR 1.43-3.78; p.

Humans

Phentermine/Topiramate in Obese, Diabetic Uric Acid Stone Formers: An Open-Label Randomized Feasibility Trial.

PURPOSE: The purpose of this study was to determine whether medical treatment of obesity, diabetes, and low urine pH with combination phentermine/topiramate affects uric acid (UA) kidney stone burden. MATERIALS AND METHODS: Participants with obesity, diabetes mellitus, normal renal function, urine pH < 5.8, and stone analysis &#x2265; 80% UA were block randomized (2:1 ratio) to phentermine 18.75 mg/topiramate 100 mg vs pragmatic controls for an 18-month, prospective, open-label feasibility study with dose escalation. The primary outcome was change in CT stone volume. Secondary outcomes included medication adherence; patient safety; and change in anthropometrics, laboratory studies, and body composition. RESULTS: Nineteen participants (age 62.1 &#xb1; 9.8 years; 68% male; mean BMI = 36.3 &#xb1; 2.9 kg/m2) were randomized, and 15 completed the study with 73% pill adherence and no serious adverse events. Stone volume by intention-to-treat analysis fell by 52% in the intervention group and rose by 8.6% in the control group (P = .10), with per-protocol analysis demonstrating statistically significant stone volume reduction (P = .02). At study end and compared with means of controls, the intervention group had greater weight loss (-10.2 vs +2.9 kg), reduction in hemoglobin A1c levels (-0.2 vs +0.5), lower 24-hour urine citrate (309 &#xb1; 81 vs 951 &#xb1; 782 mg), and lower UA supersaturation (0.7 &#xb1; 1.1 vs 1.8 &#xb1; 1.0), along with higher 24-hour urine pH (6.2 &#xb1; 0.5 vs 5.5 &#xb1; 0.4) and calcium phosphate supersaturation (0.9 &#xb1; 0.8 vs 0.2 &#xb1; 0.1; all P < .05). CONCLUSIONS: Among obese participants with diabetes mellitus and UA nephrolithiasis, phentermine/topiramate was well tolerated and demonstrated significant stone burden reductions by per-protocol analysis. The intervention group also had greater weight loss, higher urinary pH, and lower hemoglobin A1c and urinary citrate levels. These data provide a framework to study the impact of this novel alternative UA therapy on a wider range of patients with obesity and diabetes.

Aged

Integrated genomic and biochemical diagnosis of a novel homozygous start-loss variant in AKR1D1 associated with neonatal cholestasis.

INTRODUCTION: Congenital bile acid synthesis defects are rare autosomal recessive disorders that typically present in early infancy with cholestasis, progressive liver dysfunction, and, in severe cases, acute liver failure. These conditions may mimic other metabolic diseases detected in newborn screening, complicating early diagnosis. The AKR1D1 gene encodes &#x394;4-3-oxosteroid 5&#x3b2;-reductase, a key enzyme in primary bile acid synthesis, and pathogenic variants cause bile acid synthesis defect type 2 (OMIM #235555). CASE DESCRIPTION: We report a 3-month-old male infant with severe neonatal cholestasis and a history of elevated tyrosine levels in newborn screening. Pregnancy was high risk and unmonitored, with birth outside a hospital. Parental consanguinity was first-degree. Early metabolic evaluation showed transient normalization of tyrosine levels, but subsequent analyses revealed recurrent hyper-tyrosinemia. Urinary organic acids showed increased 4-hydroxyphenyl metabolites, with absent succinylacetone, excluding tyrosinemia type I. Progressive cholestasis developed, accompanied by coagulopathy, hyperbilirubinemia, hyperammonemia, and markedly elevated alpha-fetoprotein. Imaging revealed no structural liver abnormalities. Clinical exome sequencing identified a novel homozygous start-loss variant in AKR1D1, likely abolishing functional enzyme production. Metabolic studies confirmed increased urinary excretion of 3-oxocholenoic acids consistent with abnormal bile acid synthesis and supporting a diagnosis of bile acid synthesis defect type 2. Oral cholic acid therapy led to stabilization and improvement in clinical and biochemical parameters. DISCUSSION/CONCLUSION: This case illustrates the diagnostic complexity of neonatal cholestasis, particularly when initial metabolic findings suggest alternative etiologies. It highlights the importance of newborn screening as a tool for broader diagnostic suspicion and the critical role of early molecular diagnosis and multidisciplinary care. Timely recognition and targeted therapy can improve outcomes, prevent liver transplantation, and enable accurate genetic counseling, especially in consanguineous families.

Humans

Recovery of polysaccharides from marc and pomace through sequential extractions assisted by ultrasound, enzymes and acid maceration.

This study evaluated the pilot-scale recovery of polysaccharides from Vitis vinifera pomace/marc using sequential extraction strategies combining high-power ultrasound (UAE), enzymes (EAE), and acid maceration (AAE). Laboratory-scale trials identified optimal conditions for enzyme dosage and liquid/solid ratio (L/S). Pilot-scale trials demonstrated that the extraction sequence and the processing byproducts influenced extraction efficiency, total soluble polysaccharide in the extract (TSP), and polysaccharide composition. Post-maceration at pH&#xa0;3.2, with/without the maximum enzyme dose after UAE in a L/S of 1.3/1, improved structural polysaccharide extraction from Viura pomace, while Tempranillo marc showed better recovery of pectic families and TSP with UAE&#xa0;+&#xa0;EAE. Separating grape pomace extract (UAE) from the post-maceration stage at pH&#xa0;3.2 produced two extracts: E1, with higher yield (19.9%), enriched in structural polysaccharides and oligosaccharides, and E2, enriched in high and medium molecular weight pectic polysaccharides (58.03%), a low degree of esterification (17.1%) and more complex rhamnogalacturan structures.

Polysaccharides

Tranexamic acid in spontaneous&#x2002;intracerebral&#x2002;hemorrhage: an updated systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Tranexamic acid (TXA) is a well-established antifibrinolytic medication in the general population. However, its efficacy and safety for patients with spontaneous intracerebral hemorrhage (ICH) remain inconclusive. Consequently, we conducted a systematic review and meta-analysis to assess the effectiveness and safety of TXA for spontaneous ICH. METHODS: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) following established methodological standards. Our search encompassed eight electronic databases from inception to April 25, 2024. The primary outcome was a reduction in all-cause mortality. The secondary outcomes included improvements in functional independence, neurological impairment, activities of daily living, and reduction in hematoma expansion (HE). Fixed-effects or random-effects model&#xa0;were performed for pooled data where eligible. RESULTS: A total of 9 RCTs that initially enrolled 3,124 patients were included. There were no significant differences observed concerning all-cause mortality (RR, 1.03; 95% CI [0.89-1.18]), hematoma expansion (RR, 0.90; 95% CI [0.80-1.00]), improvement of functional independence (RR, 1.02; 95% CI [0.92-1.12], neurological impairment (MD, -0.88 [95% CI, -2.22-0.45]), or activities in daily living (MD, -0.83 [95% CI, -29.25-12.59]). The pooled data indicated that TXA for ICH was associated with a decrease in hematoma volume from baseline (MD, -1.74; 95% CI [-2.47 to -1.02]). No significant difference in adverse events was observed between the TXA group and the control group. CONCLUSIONS: In summary, TXA does not affect all-cause mortality, functional outcomes, or neurological impairment, nor does it reduce HE, despite reducing hematoma volulume. TXA use for ICH requires careful clinical consideration.

Humans

Multiomic insights into fungal polylactic acid degradation: Metabolic adaptation and hydrolytic mechanisms of Sporobolomyces pararoseus.

Polylactic acid (PLA), a biodegradable polyester from renewable resources, is a sustainable alternative to petrochemical plastics. However, its environmental degradation is inefficient naturally, requiring specific microbial activities. While bacterial PLA-degrading mechanisms are well documented, fungal degrading systems-particularly their molecular mechanisms-are underexplored.We isolated Sporobolomyces pararoseus ZRQ01 from the gut microbiota of PLA-fed mealworms. This fungal strain noticeably degraded PLA in PLA-containing medium supplemented with 2% glucose. Biodegradation assays revealed 22.8% loss of the PLA film weight after 35&#xa0;days of incubation, and scanning electron microscopy confirmed extensive surface erosion and pore formation. Integrated transcriptomic and proteomic analyses, together with the reference genome of S. pararoseus ZRQ01, revealed that S. pararoseus ZRQ01 upregulates hydrolytic enzymes at both transcript and protein levels to cleave PLA into lactic acid. After lactic acid is transferred into S. pararoseus ZRQ01 cells by monocarboxylate transporters with increased abundance, it is assimilated by pathways of pyruvate metabolism and the TCA cycle with increased protein abundance. Intriguingly, upregulation of genes in autophagy-related and MAPK signaling pathways underscores an adaptive stress response potentially supporting cellular homeostasis and degradation-related gene expression. Our results highlight S. pararoseus ZRQ01's metabolic potential for bioremediation and offer insights into fungal bioplastic degradation pathways.

Polyesters

Carboxyl group number and acidity of organic acids regulate structural reorganization and low glycemic index in cassava pyrodextrins via molecular interactions.

Transforming high-glycemic cassava starch into functional dietary fiber via pyrodextrinization is a promising way to valorize tuber crops, yet the molecular mechanisms catalyzed by organic acids with different carboxyl numbers and acidity remain unclear. This study investigates how carboxyl number and acidity of acetic acid (AA), tartaric acid (TA), and citric acid (CA) affect structural reorganization and low glycemic properties of cassava pyrodextrins. Compared with AA, TA, and CA with stronger acidity and more carboxyl groups promoted more extensive hydrolysis, transglycosylation, repolymerization, and esterification. These changes increased indigestible glycosidic linkages and the branching degree, while reducing molecular weight. Molecular docking confirmed stronger hydrogen-bonding interactions between TA/CA and starch chains. Furthermore, TA- and CA-catalyzed pyrodextrins exhibited superior anti-digestive properties with resistant starch up to 54.26% and an estimated glycemic index as low as 42.46, highlighting the critical role of carboxyl numbers and acidities in modulating the functionality of pyrodextrins.

Manihot

Improved comprehensive profiling of fecal bile acids through chemical derivatization combined with HPLC-MS/MS analysis.

Bile acids (BAs) facilitate the digestion and absorption of fats and influence lipid and glucose homeostasis, making them potential therapeutic targets for obesity and related metabolic disorders. The liver and intestinal microbiota modify BAs structurally, generating diverse chemical forms and isomers. Comprehensive profiling of the BA pool is critical for understanding their key biological functions and as a therapeutic approach for related diseases. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) is usually chosen as the preferred method for BA detection due to the complex chemical structures, the wide range of actual concentrations and the complexity of fecal sample matrices. However, free BAs are difficult to ionize, resulting in low detection signals and a lack of characteristic structural fragments to assist in structural identification. In this method, the labeling reagent (2-aminoethyl) trimethylammonium (AETMA) is employed to label the carboxyl group of BAs. Compared with underivatized BAs, the detection sensitivity of unconjugated BAs was enhanced by 25-180 fold, while that of conjugated BAs increased by 6-160 fold. It also generates unique fragment ions and enhances MS response, facilitating the discovery of potential BAs. Methodological parameters were validated using 38 BAs as representatives. Through methodological validation, it was verified that the precision, recovery, matrix effect and stability parameters of the method met acceptable criteria. We also identified 61 confirmed BAs and 55 additional candidate BAs in human pooled fecal samples. It has been successfully applied to fecal BA analysis in obese populations, providing valuable insights into potential therapeutic strategies for obesity.

Tandem Mass Spectrometry

Fatty acids and breast cancer: Epidemiology, subtype-specific metabolism, immune regulation, and clinical translation.

Fatty acids (FAs) are bioactive dietary and metabolic molecules that participate in membrane architecture, energy homeostasis, inflammatory signaling, gene regulation and immune function, all of which intersect with breast cancer (BC) risk, progression and treatment response. In this narrative review we integrate epidemiological, clinical, translational and mechanistic evidence on the role of FAs in BC. Saturated, monounsaturated, trans- and polyunsaturated FAs (PUFAs) are treated as distinct biological exposures rather than interchangeable measures of total fat intake. Similarly, evidence from dietary assessment, circulating biomarkers, erythrocyte membrane composition, adipose tissue stores and tumor lipid signatures is interpreted separately, because each captures exposure and biology at a different level. BC subtypes differ in FA synthesis, uptake, oxidation, storage and remodeling: luminal tumors are frequently linked to hormone-regulated lipogenesis, human epidermal growth factor receptor 2 (HER2)-positive tumors to growth-factor-driven lipid metabolism, and triple-negative tumors to exogenous FA uptake, inflammatory lipid mediators and ferroptosis-related vulnerabilities. FA-derived mediators also shape immune-cell polarization, cytokine signaling and the tumor microenvironment, and dietary FAs may reshape the gut microbiota; the fiber-derived short-chain FAs it produces, distinct from dietary FAs, likewise help regulate immune and inflammatory tone. Clinical data suggest possible roles for fat-quality modification and selected n-3 PUFA interventions, but findings are heterogeneous and not yet sufficient to support routine biomarker-guided precision onco-nutrition. Candidate biomarkers, such as erythrocyte n-6:n-3 composition, require prospective validation before clinical implementation. FA biology thus represents a modifiable but complex axis in BC prevention, tumor biology and supportive care.

Humans

Probiotic supplementation improves body composition, lipid profiles, and fatty acid metabolism in combat sports athletes during the weight reduction phase.

PURPOSE: Pre-competition weight control for combat sports athletes may alter body composition and fatty acid metabolism. Probiotics have shown potential to regulate overall metabolism; however, their specific effects on fatty acid metabolism during weight control in athletes remain unclear. METHODS: Thirty-two combat sports athletes participating in the 4-week weight reduction period were assigned to either the probiotic group (Group E) or the placebo group (Group C). Body composition, lipid profiles, and fatty acid metabolism were measured before and after the 4-week weight reduction phase. RESULTS: All the athletes experienced a decrease in body weight, body mass index (BMI), body fat percentage, and muscle mass following the 4-week weight loss intervention. Notably, a more significant reduction in body fat percentage (p&#x2009;<&#x2009;0.05) was observed, along with lower levels of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), specifically in Group E. Weight loss intervention resulted in increased levels of short-chain fatty acids (SCFAs), specifically acetic acid, propionic acid, and butyric acid. Notably, Group E exhibited higher mean values for SCFAs compared to Group C (p&#x2009;<&#x2009;0.05). Additionally, the serum levels of &#x3b3;-linolenic acid and 8,11,14-eicosatrienoic acid were significantly reduced in Group E (p&#x2009;<&#x2009;0.05). In contrast, the majority of free fatty acids (FFAs) showed significant increases, with greater magnitudes of change observed in Group C (p&#x2009;<&#x2009;0.05). CONCLUSION: Probiotic supplementation can improve body composition, enhance SCFAs levels, and decrease circulating FFAs in combat sports athletes, suggesting that probiotics may have a beneficial impact on pre-competition weight management. TRIAL REGISTRATION NUMBER: chiCTR2400079908 (Reg Date:2024-01-16).

Humans