Fatty Acid Binding Protein Research Articles

Probiotics may alleviate intestinal damage induced by cardiopulmonary bypass in children.

Intestinal ischaemia-reperfusion injury induced by cardiopulmonary bypass causes intestinal epithelial barrier dysfunction, leading to dysbiosis and bacterial translocation. We conducted a randomized prospective study with 2 objectives: (i) to investigate epithelial barrier dysfunction and bacterial translocation induced by cardiopulmonary bypass and changes in the gut microbiota and (ii) to verify whether probiotics can improve these conditions. Between 2019 and 2020, patients 0-15 years old scheduled to undergo cardiac surgery using cardiopulmonary bypass were enrolled and randomly allocated to 2 groups: the intervention group received probiotics and the control group did not receive probiotics. We analysed the microbiota in faeces and blood, organic acid concentrations in faeces, plasma intestinal fatty acid-binding protein and immunological responses. Eighty-two patients were enrolled in this study. The characteristics of the patients were similar in both groups. The total number of obligate anaerobes was higher in the intervention group than in the control group after postoperative day 7. We identified 4 clusters within the perioperative gut microbiota, and cluster changes showed a corrective effect of probiotics on dysbiosis after postoperative day 7. Organic acid concentrations in faeces, incidence of bacterial translocation, intestinal fatty acid-binding protein levels and immunological responses, except for interleukin -17A, were not markedly different between the 2 groups. Administration of probiotics was able to correct dysbiosis but did not sufficiently alleviate the intestinal damage induced by cardiopulmonary bypass. More effective methods should be examined to prevent disturbances induced by cardiac surgery using cardiopulmonary bypass. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000037174 UMIN000035556.

Markers of intestinal barrier damage in patients with chronic insomnia disorder.

Insomnia disorder stands out as one of the prevalent clinical sleep and psychiatric disorders. Prior research has unequivocally demonstrated variations in the diversity and abundance of gut microbiota among individuals with insomnia disorder. These alterations may play a direct or indirect role in the onset and progression of insomnia disorder by compromising the integrity of the intestinal barrier. This study aims to evaluate the impairment of the intestinal barrier in individuals with insomnia disorder by scrutinizing the serum functionality of this barrier. 45 patients with chronic insomnia disorder and 30 matched healthy volunteers were meticulously selected based on inclusion criteria. ELISA technology was employed to measure serum levels of diamine oxidase (DAO), D-lactic acid (D-LA), intestinal fatty acid binding protein (I-FABP), and endothelin (ET). Spearman correlation analysis was used to explore the relationship between intestinal mucosal markers and clinical characteristics. Data were analyzed using SPSS 26.0. Compared to the healthy control group, the insomnia disorder group exhibited significantly elevated scores on subjective mood and sleep scales (GAD-7, PHQ-9, HAMA, HAMD, PSQI, and ISI) (P < 0.05). Overnight PSG indicated a notable increase in bed time, total wake time, sleep onset latency, and wake after sleep onset in individuals with insomnia disorder. Additionally, there was a decrease in sleep efficiency and alterations in sleep structure (increased proportion of N1 and N3 stages, prolonged N1 stage) (P < 0.05). The chronic insomnia disorder group displayed significantly reduced concentrations of serum DAO, D-LA, I-FABP, and ET (P < 0.05). Furthermore, significant positive correlations were identified between intestinal epithelial barrier markers and sleep efficiency, while negative correlations were found with wake after sleep onset, total wake time, PSQI, HAMA, and HAMD. Additionally, D-LA levels were significantly positively correlated with ET concentrations. Individuals with chronic insomnia disorder manifest disruptions in sleep structure, heightened susceptibility to anxiety and depressive moods, and impaired intestinal barrier function. These findings suggest that the occurrence and development of insomnia disorder may be linked to the impairment of the intestinal barrier.

Gut permeability is associated with lower insulin sensitivity in youth living with perinatally-acquired HIV.

The relationships between alterations in the intestinal barrier, and bacterial translocation with the development of metabolic complications in youth with perinatally-acquired HIV (YPHIV) have not been investigated. The PHACS Adolescent Master Protocol enrolled YPHIV across 15 U.S. sites, including Puerto Rico, from 2007-2009. For this analysis, we included YPHIV with HIV viral load ≤1000 c/mL, with at least one measurement of homeostatic assessment of insulin resistance (HOMA-IR) or non-high density lipoprotein (non-HDLc) between baseline and year 3 and plasma levels of intestinal fatty-acid binding protein (I-FABP), lipopolysaccharide binding protein (LBP), and zonulin levels at baseline. We fit linear regression models using generalized estimating equations to assess the association of baseline log10 gut markers with log10 HOMA-IR and non-HDLc at all timepoints. HOMA-IR or non-HDLc was measured in 237, 189, and 170 PHIV at baseline, Yr2, and Yr3, respectively. At baseline, median age (Q1, Q3) was 12 yrs (10, 14), CD4 count was 762 cells/mm3 (574, 984); 90% had HIV RNA <400 c/mL. For every 10-fold higher baseline I-FABP, HOMA-IR dropped 0.85-fold at baseline and Yr2. For a 10-fold higher baseline zonulin, there was a 1.35-fold increase in HOMA-IR at baseline, 1.23-fold increase in HOMA-IR at Yr2, and 1.20-fold increase in HOMA-IR at Yr3 in adjusted models. For a 10-fold higher baseline LBP, there was a 1.23-fold increase in HOMA-IR at baseline in the unadjusted model, but this was slightly attenuated in the adjusted model. Zonulin was associated with non-HDLc at baseline, but not for the other time points. Despite viral suppression, intestinal damage may influence downstream insulin sensitivity in YPHIV.

Alcohol-Associated Liver Disease Outcomes: Critical Mechanisms of Liver Injury Progression.

Alcohol-associated liver disease (ALD) is a substantial cause of morbidity and mortality worldwide and represents a spectrum of liver injury beginning with hepatic steatosis (fatty liver) progressing to inflammation and culminating in cirrhosis. Multiple factors contribute to ALD progression and disease severity. Here, we overview several crucial mechanisms related to ALD end-stage outcome development, such as epigenetic changes, cell death, hemolysis, hepatic stellate cells activation, and hepatic fatty acid binding protein 4. Additionally, in this review, we also present two clinically relevant models using human precision-cut liver slices and hepatic organoids to examine ALD pathogenesis and progression.

Gut barrier dysfunction and the risk of ICU-acquired bacteremia- a case–control study

BackgroundImpaired intestinal barrier function can enable passage of enteric microorganisms into the bloodstream and lead to nosocomial bloodstream infections during critical illness. We aimed to determine the relative importance of gut translocation as a source for ICU-acquired enterococcal bacteremia of unknown origin.MethodsWe conducted a nested case–control study in two mixed medical-surgical tertiary ICUs in the Netherlands among patients enrolled between 2011 and 2018. We selected 72 cases with ICU-acquired bacteremia due to enterococci (which are known gastrointestinal tract commensals) and 137 matched controls with bacteremia due to coagulase-negative staphylococci (CoNS) (which are of non-intestinal origin). We measured intestinal fatty acid-binding protein, trefoil factor-3, and citrulline 48 h before bacteremia onset. A composite measure for Gut Barrier Injury (GBI) was calculated as the sum of standardized z-scores for each biomarker plus a clinical gastrointestinal failure score.ResultsNo single biomarker yielded statistically significant differences between cases and controls. Median composite GBI was higher in cases than in controls (0.58, IQR − 0.36–1.69 vs. 0.32, IQR − 0.53–1.57, p = 0.33) and higher composite measures of GBI correlated with higher disease severity and ICU mortality (p < 0.001). In multivariable analysis, higher composite GBI was not significantly associated with increased occurrence of enterococcal bacteremia relative to CoNS bacteremia (adjusted OR 1.12 95% CI 0.93–1.34, p = 0.22).ConclusionsWe could not demonstrate an association between biomarkers of gastrointestinal barrier dysfunction and an increased occurrence of bacteremia due to gut compared to skin flora during critical illness, suggesting against bacterial translocation as a major vector for acquisition of nosocomial bloodstream infections in the ICU.

Single-cell sequencing analysis and multiple machine-learning models revealed the cellular crosstalk of dendritic cells and identified FABP5 and KLRB1 as novel biomarkers for psoriasis.

Psoriasis is an immune-mediated disorder influenced by environmental factors on a genetic basis. Despite advancements, challenges persist, including the diminishing efficacy of biologics and small-molecule targeted agents, alongside managing recurrence and psoriasis-related comorbidities. Unraveling the underlying pathogenesis and identifying valuable biomarkers remain pivotal for diagnosing and treating psoriasis. We employed a series of bioinformatics (including single-cell sequencing data analysis and machine learning techniques) and statistical methods to integrate and analyze multi-level data. We observed the cellular changes in psoriatic skin tissues, screened the key genes Fatty acid binding protein 5 (FABP5) and The killer cell lectin-like receptor B1 (KLRB1), evaluated the efficacy of six widely prescribed drugs on psoriasis treatment in modulating the dendritic cell-associated pathway, and assessed their overall efficacy. Finally, RT-qPCR, immunohistochemistry, and immunofluorescence assays were used to validate. The regulatory influence of dendritic cells (DCs) on T cells through the CD70/CD27 signaling pathway may emerge as a significant facet of the inflammatory response in psoriasis. Notably, FABP5 and KLRB1 exhibited up-regulation and co-localization in psoriatic skin tissues and M5-induced HaCaT cells, serving as potential biomarkers influencing psoriasis development. Our study analyzed the impact of DC-T cell crosstalk in psoriasis, elucidated the characterization of two biomarkers, FABP5 and KLRB1, in psoriasis, and highlighted the promise and value of tofacitinib in psoriasis therapy targeting DCs.

Biomarkers and predictors of postoperative necrotizing enterocolitis in neonates with duct-dependent congenital heart defects undergoing cardiac surgery: a cohort study

The development of necrotizing enterocolitis (NEC) in neonates with duct-dependent congenital heart defects (CHD) who underwent cardiac surgery is accompanied by high mortality. Analysis of predictors is necessary for understanding the pathophysiology of NEC and development of approaches for prevention to achieve favorable outcomes of cardiac surgery. The purpose of the study was to develop a prognostic model for predicting the development of NEC after cardiac surgery in neonates with duct-dependent CHD. Methods. A prognostic cohort study was performed that included full-term neonates with duct-dependent CHD who underwent cardiac surgery at the Almazov National Medical Research Center from January 2021 to September 2023. The outcome was the development/absence of stage IB-III NEC in the postoperative period. Biomarkers of NEC (intestinal fatty acid binding protein (i-FABP, ng/ml), claudin-3 (CLDN3, ng/ml), calprotectin (CALPR, ng/ml), ischemia modified albumin (IMA, ng/ml), vascular endothelial growth factor A (VEGF A, pg/ml)) were measured by ELISA in the blood serum before cardiac surgery and 12-14 hours after surgery. We also analyzed clinical characteristics of neonates, C-reactive protein levels, complete blood count, abdominal ultrasound, ejection fraction (EF, Teicholtz) in the preoperative and postoperative periods, surgical parameters, P(v-a)CO2/C(a-v)O2 upon arrival from the operating room, vasoactive inotropic score (VIS) and arterial blood lactate levels in the first 24 hours after surgery. The association between predictors and the development of NEC after cardiac surgery was assessed using univariate and multivariate logistic regression analysis. Internal validation of the model was performed using 10-fold cross-validation. Results. During the observation period, 187 neonates underwent surgical treatment of duct-dependent CHD, of which 32 children developed stage IB-III NEC in the postoperative period (17.1%), two neonates required surgical treatment of NEC (6.3%). After meeting the non-inclusion and exclusion criteria, two groups of patients were formed: a main group (30 neonates who developed stages IB-III NEC in the postoperative period, of which stage III NEC was in one neonate) and a comparison group (40 neonates without NEC). Groups were comparable by types of CHD. Predictors associated with NEC (univariate analysis): intrauterine growth retardation (IUGR), formula feeding before surgery, high levels of IMA before on the first postoperative day (POD), procedures performed before surgery (Rashkind procedure/valvuloplasty/stenting), lower EF in in the early postoperative period, a higher maximum level of VIS in the first 24 hours after surgery, as well as a higher level of IR in the superior mesenteric artery (SMA) and thickening of the intestinal wall on the first postoperative day (POD) Independent preoperative predictors of NEC (AUC of model 0.885, specificity 0.867): IUGR (OR 32.2 (1.4-730.3), p=0.029), formula feeding (OR 12.6 (2.6-60.2), p=0.002), IMA level before surgery (OR 1.03 (1.01-1.04), p=0.004), CLDN3 level before surgery (OR 0.5 (0.3-0.9), p=0.013). Independent early postoperative predictors of NEC: IMA level on 12-14 hour after surgery (OR 1.02 (1.01-1.03), p=0.030), P(v-a)CO2/C(a-v)O2 immediately after surgery (OR 2.3 (1.2-4.4), p=0.008), IR&gt;0.93 in SMA (OR 7.2 (1.6-32.4), p=0.011) and thickness of intestinal wall by ultrasound on POD 1 (OR 4.9 (1.3-19.2), p=0.021). Adding of VEGF A level (12-14 hour after surgery, negatively associated with NEC) to the model increased the specificity, but the predictor was not significant. AUC of postoperative model 0.862, specificity 0.800. The final model included preoperative (IUGR, formula feeding) and postoperative predictors (IMA, P(v-a)CO2/C(a-v)O2, IR of SMA&gt;0.93, intestinal wall thickness), AUC=0.921, specificity 0.83. Conclusion. The identified predictors indirectly indicate the role of hypoxia in the pathophysiology of NEC in term neonates with duct-dependent CHD. Breast milk feeding/mixed feeding in the preoperative period may help reduce the risk of NEC in the postoperative period. Low levels of CLDN3 before surgery were associated with the development of NEC, but the interpretation of the result is controversial.

Recent Advances on Small-Molecule Inhibitors of Lipocalin-like Proteins.

Lipid transfer proteins (LTPs) are crucial players in nonvesicular lipid trafficking. LTPs sharing a lipocalin lipid transfer domain (lipocalin-like proteins) have a wide range of biological functions, such as regulating immune responses and cell proliferation, differentiation, and death as well as participating in the pathogenesis of inflammatory, metabolic, and neurological disorders and cancer. Therefore, the development of small-molecule inhibitors targeting these LTPs is important and has potential clinical applications. Herein, we summarize the structure and function of lipocalin-like proteins, mainly including retinol-binding proteins, lipocalins, and fatty acid-binding proteins and discuss the recent advances on small-molecule inhibitors for these protein families and their applications in disease treatment. The findings of our Perspective can provide guidance for the development of inhibitors of these LTPs and highlight the challenges that might be faced during the procedures.

Endari treatment ameliorates sickle cell-related disruption in intestinal barrier functions and is associated with prolonged survival in sickle cell mice

ABSTRACT Background Endari (L-glutamine) is a conditional amino acid that reduces the frequency of vaso-occlusive crisis (VOC) in sickle cell disease (SCD). Aim To investigate whether Endari could ameliorate intestinal barrier function and improve survival outcomes in SCD. Methods We treated female Townes SCD mice with Endari and evaluated their intestinal barrier functions by measuring the recovery of orally administered fluorescein isothiocyanate (FITC)-conjugated dextran 4 kDa in serum, and serum intestinal fatty acid binding proteins (iFABP) and lipopolysaccharide (LPS) concentrations by ELISA. We also explored the impact the Endari has on the survival of the SCD mice that underwent repeated experimentally-induced VOC. Results Compared to SCD mice treated with water only, Endari-treated mice showed improved intestinal barrier functions, with decrease in the barrier permeability and reduction in the translocation of lipopolysaccharides from the intestinal lumen into the circulation. These changes occurred after only 4 weeks of Endari treatment. Improved intestinal barrier function was also associated with prolonged survival in Endari-treated SCD mice after repeated experimentally-induced VOC. Conclusion Our findings provide the evidence supporting the beneficial effects of Enadri in improving intestinal barrier function and associated survival outcomes in SCD.

Abstract 5451: FOXC2 influences EMT-induced stem cell properties through regulation of FABP4 in breast cancer

Abstract Cancer stem cells (CSCs) pose a significant clinical challenge due to their inherent resistance to therapies and prevalence in cancer recurrence. CSCs have the ability for self-renewal and to adapt to different microenvironments during dissemination and seeding into distal organs, and these properties are critical in metastasis. We and others have shown that epithelial to mesenchymal transition (EMT) drives the acquisition of stem cell properties, particularly via the forkhead box protein C2 (FOXC2) transcription factor. FOXC2 is a master regulator of EMT and is necessary for the induction and maintenance of CSC properties. Importantly, FOXC2 is not expressed in most adult tissues except adipocytes, in which it dictates several aspects of lipid metabolism. Additionally, metabolic changes during EMT can equip cancer cells with enhanced survival mechanisms during tumor progression and metastasis. We hypothesized that FOXC2 regulates metabolism in EMT-induced cells, facilitating stem cell properties and metastatic competence. To determine the downstream metabolic genes regulated by FOXC2 and that enhance stemness properties in cancer cells, we performed gene expression profiling and identified fatty acid binding protein 4 (FABP4), which is known to be involved in lipid metabolism, especially in adipocytes and macrophages. We demonstrate that inhibition of FOXC2 expression using shRNA in EMT-induced cells markedly reduces FABP4 expression. In agreement with this, we found that the overexpression of FOXC2 expression rescues the expression of FABP4. In addition, FOXC2 binds to the FABP4 promoter and regulates its expression suggesting that FABP4 is a direct target of FOXC2. We demonstrate that both lipid uptake and CSC formation is inhibited in a dose-dependent manner using a FABP4-specific small molecule inhibitor. Additional experiments are underway to assess the role of FABP4 in CSC formation in vivo and in contributions to metastasis, using our small molecule inhibitor in mouse models of metastatic breast cancer. Overall, our data indicate that FABP4 is a key regulator of stemness in breast cancer cells and targeting the FOXC2—FABP4 axis may provide therapeutic benefits for breast cancer. This work also provides insights into the metabolic shifts that occur during EMT and CSC formation, which warrants further investigation into these mechanisms. Citation Format: Breanna R. Demestichas, Vinita Shivakumar, Esmeralda Ramirez-Peña, Joseph Taube, Petra den Hollander, Sendurai A. Mani. FOXC2 influences EMT-induced stem cell properties through regulation of FABP4 in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5451.

Abstract 4466: Omega-3 fatty acid-induced ferroptosis in 4T1 breast cancer through CD36/FABP5 axis

Abstract Mammalian cells utilize energy from many different sources, and fatty acids are one of these sources. Dietary fats contain various structures of fatty acids, each impacting cell lipid metabolism in unique ways. Omega-3 fatty acids are known to induce breast cancer cell death through ferroptosis. However, the specific molecular mechanisms by which omega-3 fatty acids trigger ferroptosis have yet to be fully elucidated. Fatty acid binding proteins (FABPs) constitute a family of evolutionarily conserved lipid chaperones, facilitating the transport and utilization of fatty acids within cells. Notably, FABP5 is highly expressed in breast cancer, especially in the most aggressive form, triple-negative breast cancer. We hypothesized that FABP5 acts as a lipid sensor, mediating the ferroptosis induced by omega-3 fatty acids in triple-negative breast cancer cells. To test this, we created Fabp5 stable knockout cell lines in 4T1 and MDA-MB-231, two commonly used triple-negative breast cancer cell lines, using CRISPR/Cas9 technology. When treated with docosapentaenoic acid (DPA), these Fabp5-knockout cells exhibited reduced ferroptosis compared to their wild-type counterparts. Interestingly, blocking the surface protein CD36, either with inhibitors or antibodies, also reduced DPA-induced ferroptosis. Furthermore, mutations in Fabp5 decreased maximal mitochondrial respiration in both 4T1 and MDA-MB-231 cells, suggesting a crucial role for FABP5 in mediating oxygen consumption and reactive oxygen species (ROS) production during DPA-induced ferroptosis. Additionally, mice fed a high-fat diet rich in omega-3 fatty acids showed reduced tumor size and lung metastasis. Collectively, our data indicate that FABP5 is a key molecular sensor mediating oxygen consumption and ROS production, thus contributing to ferroptosis induced by omega-3 fatty acids in triple-negative breast cancer. Citation Format: Anthony Avellino, Jiaqing Hao, Matthew Yorek, Jian yu, Bing Li. Omega-3 fatty acid-induced ferroptosis in 4T1 breast cancer through CD36/FABP5 axis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4466.

Abstract 5910: Developing a novel humanized anti-FABP4 antibody for breast cancer treatment

Abstract Circulating levels of adipocyte fatty acid binding protein (A-FABP, also known as FABP4) are linked with metabolic dysregulation. Our previous study demonstrated that high serum levels of FABP4 increased the risk of breast cancer, indicating that circulating FABP4 could be a potential therapeutic target for this disease. In this study, we generated mouse monoclonal antibodies (mAb) against FABP4 by immunizing C57BL/6 mice with recombinant human FABP4. After screening over 1300 hybridoma clones, we identified an FABP4 neutralizing mAb, named 12G2, which inhibited breast cancer growth in various mouse models. To facilitate clinical application, we engineered chimeric and humanized variants of the 12G2 mAb. Notably, the humanized variant, 12G2-variant 9 (12G2-vt9), effectively inhibited mammary tumor growth and progression by reducing the activity of FABP4/ALDH1 in different breast cancer mouse models. Our findings suggest that 12G2-Vt9 is a promising neutralizing mAb targeting FABP4-mediated cancer stemness through ALDH1 signaling, offering potential as a targeted therapeutic antibody for the clinical treatment of breast cancer. Citation Format: Jiaqing Hao, Matthew Yorek, Jian yu, Anthony Avellino, Bing Li. Developing a novel humanized anti-FABP4 antibody for breast cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5910.

Abstract 766: Effects of supplemental calcium and vitamin D on circulating biomarkers of gut barrier function in colorectal adenoma patients: A randomized controlled trial

Abstract Introduction: Recent experimental evidence shows that intestinal barrier disruption initiates colon inflammation, which may promote colorectal carcinogenesis. In experimental models, vitamin D and calcium improved gut barrier function; however, this has not been assessed in humans. Method: To test the effects of supplemental calcium and vitamin D3 on circulating biomarkers of intestinal mucosal damage (intestinal fatty-acid binding protein, IFABP) and exposure to bacterial products due to impaired gut barrier (lipopolysaccharide-binding protein, LBP), we conducted an “adjunct biomarker study” to a larger 11-center, randomized, placebo-controlled, partial 2 × 2 factorial chemoprevention clinical trial, the Vitamin D/Calcium Polyp Prevention Study. Participants were randomized into four different treatment groups: placebo, 1,200 mg/day calcium, 1,000 IU/day vitamin D3, and 1,200 mg/day calcium plus 1,000 IU/day vitamin D3. Circulating concentrations of LBP and IFABP were measured at baseline and 1-year follow-up using the Meso Scale Discovery electrochemiluminescence assays in a subset of 118 participants included in the adjunct biomarker study. Result: Following one year of vitamin D3 treatment, in the vitamin D3 plus calcium and vitamin D3 groups versus placebo and calcium groups, LBP decreased 10% (316 ng/ml; P=0.23) and IFABP 18% (77 ng/ml; P=0.06). A similar decrease of 20% (P=0.10) was observed for IFABP, but not LBP, in the vitamin D3 plus calcium versus the calcium group. There were no appreciable biomarker changes with calcium treatment. In stratified analyses, we found possible effect modifications by baseline serum 25-OH-vitamin D, total calcium intake, body mass index, and interleukin 6 (IL-6) concentration on estimated vitamin D3 treatment effects on LBP and/or IFABP. Conclusion: These preliminary results are consistent with vitamin D’s potential protective effects on intestinal mucosal barrier and support further research of vitamin D against gut barrier disruption and colorectal neoplasms. Citation Format: Sangji Lee, Veronika Fedirko, Roberd M. Bostick, Bradley Pearce, Elizabeth L. Barry, Robin E. Rutherford, March E. Seabrook. Effects of supplemental calcium and vitamin D on circulating biomarkers of gut barrier function in colorectal adenoma patients: A randomized controlled trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 766.

Expression of Placental Lipid Transporters in Pregnancies Complicated by Gestational and Type 1 Diabetes Mellitus.

The objective of the study was to assess the expression of proteins responsible for placental lipid transport in term pregnancies complicated by well-controlled gestational (GDM) and type 1 diabetes mellitus (PGDM). A total of 80 placental samples were obtained from patients diagnosed with PGDM (n = 20), GDM treated with diet (GDMG1, n = 20), GDM treated with diet and insulin (GDMG2, n = 20), and a non-diabetic control group (n = 20). Umbilical and uterine artery blood flows were assessed by means of ultrasound in the period prior to delivery and computer-assisted quantitative morphometry of immunostained placental sections was performed to determine the expression of selected proteins. The morphometric analysis performed for the vascular density-matched placental samples demonstrated a significant increase in the expression of fatty acid translocase (CD36), fatty acid binding proteins (FABP1, FABP4 and FABP5), as well as a decrease in the expression of endothelial lipase (EL) and fatty acid transport protein (FATP4) in the PGDM-complicated pregnancies as compared to the GDMG1 and control groups (p < 0.05). No significant differences with regard to the placental expression of lipoprotein lipase (LPL) and FATP6 protein between GDM/PGDM and non-diabetic patients were noted. Maternal pre-pregnancy weight, body mass index, placental weight as well as the expression of LPL and FABP4 were selected by the linear regression model as the strongest contributors to the fetal birth weight. To conclude, in placentas derived from pregnancies complicated by well-controlled PGDM, the expression of several lipid transporters, including EL, CD36, FATP4, FABP1, FABP4 and FABP5, is altered. Nonetheless, only LPL and FABP4 were significant predictors of the fetal birth weight.

Stellera chamaejasme L. extract inhibits adipocyte differentiation through activation of the extracellular signal-regulated kinase pathway.

Stellera chamaejasme L. (SCL) is a perennial herb with demonstrated bioactivities against inflammation and metabolic dysfunction. Adipocyte differentiation is a critical regulator of metabolic homeostasis and a promising target for the treatment of metabolic diseases, so we examined the effects of SCL on adipogenesis. A methanol extract of SCL dose-dependently suppressed intracellular lipid accumulation in adipocyte precursors cultured under differentiation induction conditions and reduced expression of the adipogenic transcription factors PPARγ and C/EBPα as well as the downstream lipogenic genes fatty acid binding protein 4, adiponectin, fatty acid synthase, and stearoyl-CoA desaturase. The extract also promoted precursor cell proliferation and altered expression of the cell cycle regulators cyclin-dependent kinase 4, cyclin E, and cyclin D1. In addition, SCL extract stimulated extracellular signal-regulated kinase (ERK) phosphorylation, while pharmacological inhibition of ERK effectively blocked the inhibitory effects of SCL extract on preadipocyte differentiation. These results suggest that SCL extract contains bioactive compounds that can suppress adipogenesis through modulation of the ERK pathway.

Analysis of the types and functions of CD34+ cells in full-thickness skin defect wounds of normal mice and diabetic mice by single-cell RNA sequencing

Objective: To analyze the types and functions of CD34+ cells in full-thickness skin defect wounds of normal mice and diabetic mice by single-cell RNA sequencing. Methods: This study was an experimental study. The CD34+ cell lineage tracing mouse was produced, and the visualization of CD34+ cells under the fluorescent condition was realized. Six male CD34+ cell lineage tracing mice aged 7-8 weeks (designated as diabetic group) were intraperitoneally injected with streptozotocin to establish a diabetic model, and full-thickness skin defect wounds were prepared on their backs when they reached 13 weeks old. Another 6 male CD34+ cell lineage tracing mice aged 13 weeks (designated as control group) were also subjected to full-thickness skin defect wounds on their backs. On post-injury day (PID) 4, wound tissue was collected from 3 mice in control group and 2 mice in diabetic group, and digested to prepare single-cell suspensions. CD34+ cells were screened using fluorescence-activated cell sorting, followed by single-cell RNA sequencing. The Seurat 4.0.2 program in the R programming language was utilized for dimensionality reduction, visualization, and cell clustering analysis of CD34+ cell types, and to screen and annotate the marker genes for each CD34+ cell subpopulation. Kyoto encyclopedia of genes and genomes (KEGG) and gene ontology (GO) enrichment analysis was performed to analyze the differentially expressed genes (DEGs) of CD34+ fibroblasts (Fbs), smooth muscle cells (SMCs), keratinocytes (KCs), and chondrocyte-like cells (CLCs) in the wound tissue of two groups of mice for exploring cellular functions. Results: On PID 4, CD34+ cells in the wound tissue of both groups of mice were consisted of 7 cell types, specifically endothelial cells, Fbs, KCs, macrophages, T cells, SMCs, and CLCs. Among these, Fbs were further classified into 5 subpopulations. Compared with those in control group, the proportions of CD34+ endothelial cells, Fbs subpopulation 1, Fbs subpopulation 4, KCs, and CLCs in the wound tissue of mice were increased in diabetic group, while the proportions of CD34+ Fbs subpopulation 2, Fbs subpopulation 3, and SMCs were decreased. The marker genes for annotating CD34+ CLCs, endothelial cells, Fbs subpopulation 1, Fbs subpopulation 2, Fbs subpopulation 3, Fbs subpopulation 4, Fbs subpopulation 5, KCs, macrophages, SMCs, and T cells were respectively metastasis-associated lung adenocarcinoma transcript 1, fatty acid binding protein 4, Gremlin 1, complement component 4B, H19 imprinted maternally expressed transcript, Dickkopf Wnt signaling pathway inhibitor 2, fibromodulin, keratin 5, CD74 molecule, regulator of G protein signaling 5, and inducible T-cell co-stimulator molecule. KEGG and GO enrichment analysis revealed that, compared with those in control group, DEGs with significant differential expression (SDE) in CD34+ Fbs from the wound tissue of mice in diabetic group on PID 4 were significantly enriched in terms related to inflammatory response, extracellular matrix (ECM) organization, regulation of cell proliferation, and aging (with Pvalues all <0.05), DEGs with SDE in CD34+ SMCs were significantly enriched in terms related to cell migration, apoptotic process, positive regulation of transcription, and phagosome (with P values all <0.05), DEGs with SDE in CD34+ KCs were significantly enriched in terms related to mitochondrial function, transcription, and neurodegenerative diseases (with P values all <0.05), and DEGs with SDE in CD34+ CLCs were significantly enriched in terms related to rhythm regulation, ECM, and viral infection (with P values all <0.05). Conclusions: CD34+ cells display high heterogeneity in the healing process of full-thickness skin defect wounds in both normal mice and diabetic mice. The significantly enriched functions of DEGs with SDE in CD34+ cell subpopulations in the wound tissue of the two mouse groups are closely related to the wound healing process.

Perfluorooctanoic acid inhibits cell proliferation through mitochondrial damage

Grown evidence has shown that the liver and reproductive organs were the main target organs of perfluorooctanoic acid (PFOA). Herein, we studied a toxic mechanism of PFOA using HeLa Chang liver epithelial cells. When incubated with PFOA for 24 h or 48 h, cell proliferation was inhibited in a concentration- and time-dependent fashion, but interestingly, the feature of dead cells was not notable. Mitochondrial volume was increased with concentration and time, whereas the mitochondrial membrane potential and produced ATP amounts were significantly reduced. Autophagosome-like vacuoles and contraction of the mitochondrial inner membrane were observed in PFOA-treated cells. The expression of acetyl CoA carboxylase (ACC) and p-ACC proteins rapidly decreased, and that of mitochondrial dynamics–related proteins increased. The expression of solute carrier family 7 genes, ChaC glutathione-specific gamma-glutamylcyclotransferase 1, and 5S ribosomal RNA gene was up-regulated the most in cells exposed to PFOA for 24 h, and the KEGG pathway analysis revealed that PFOA the most affected metabolic pathways and olfactory transduction. More importantly, PPAR alpha, fatty acid binding protein 1, and CYP450 family 1 subfamily A member 1 were identified as the target proteins for binding between PFOA and cells. Taken together, we suggest that disruption of mitochondrial integrity and function may contribute closely to PFOA-induced cell proliferation inhibition.

Positive effects of low-dose S-ketamine on preventing myocardial injury after thoracoscopic lobectomy in patients aged 70 to 85

ObjectiveTo investigate the effects of low-dose S-ketamine on marker of myocardial injury (BNP, hs-cTnT and HFABP) after thoracoscopic lobectomy in patients aged 70 to 85.MethodsOne hundred patients (four cases excluded) aged 70–85 years, with body mass index 18–24 kg·m−2 and American Society of Anesthesiologists physical status II–III, scheduled for elective lobectomy from April 2022 to April 2023, were selected. The patients were divided into two groups by a random number table method, namely, the low-dose S-ketamine combined with GDFT group (group S) and the control group (group C), with 48 cases in each group. In group S, a low dose of S-ketamine (0.2 mg/kg) was given 1 min before intubation, and the maintenance dose was 0.12 mg·kg−1·h−1. Fluid therapy, guided by cardiac index (CI), changes in stroke volume (△SV), and other dynamic indicators, was used for rehydration during the operation. Group C was given the same amount of normal saline (0.2 mg/kg) 1 min before intubation, and the same rehydration therapy was adopted during the operation. The mean arterial pressure (MAP) and heart rate (HR) of the two groups were observed and recorded immediately after entering the operating room (T0), immediately after intubation (T1), immediately after the beginning of one-lung ventilation (OLV) (T2), immediately after the beginning of surgery (T3), immediately after the end of OLV (T4), and at the end of surgery (T5). The intraoperative fluid intake and output and the use of vasoactive drugs were recorded. The plasma levels of heart-type fatty acid–binding protein (HFABP), high-sensitivity troponin T (hs-cTnT), brain natriuretic peptide (BNP), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) were recorded 24 h before operation and 24 and 48 h after operation. Visual analogue scale (VAS) pain scores at rest were recorded at 2 (V1), 6 (V2), 12 (V3), 24 (V4), and 48 h (V5) after operation, and the occurrence of myocardial ischemia during hospitalization was noted.ResultsCompared with group C, MAP was significantly higher at T1–T5 in group S (P < 0.05), and the plasma concentrations of IL-6, IL-8, TNF-α, BNP, hs-cTnT, and HFABP were significantly lower at 24 and 48 h after operation (P < 0.05). The VAS pain scores at 2, 6, 12, 24, and 48 h after operation, the number of effective patient-controlled intravenous analgesia (PCIA) compressions, and the total number of PCIA compressions within 48 h after operation were significantly decreased (P < 0.05). Compared with group C, The hospitalization days, and the incidence of postoperative myocardial ischemia in group S were lower (P < 0.05). There were no significant intergroup differences in urine volume, extubation time, the incidence of postoperative atrial fibrillation, bleeding volume, colloid infusion volume, total fluid infusion volume, and the incidence of rescue analgesia.ConclusionsLow-dose S-ketamine can reduce the levels of hs-cTnT, HFABP, and BNP in older patients after pulmonary lobectomy, which has a positive effect on preventing myocardial injury.Trial registrationThis study was registered on CHICTR (registration No. ChiCTR2300074475). Date of registration: 08/08/2023.

O242: Prolonged subnormothermic acellular machine perfusion of human kidneys

Abstract Introduction Prolonged periods of ex vivo perfusion are required to effectively deliver regenerative therapies directly to a kidney before transplantation. This provides time to start repair processes and reduce the likelihood of early graft dysfunction. The aim of this study was to assess the capability of extending the preservation interval using subnormothermic acelllular machine perfusion (SNAP). Methods After a period of static cold storage, 12 human kidneys declined for transplantation were perfused with an oxygenated human serum albumin-based solution at 32°C for 6, 12 or 24h (n=4 per group). After preservation all kidneys were reperfused with a red blood cell-based solution at 37°C for 4h for assessment. Results Functional parameters remained stable during SNAP in all kidneys. However, the perfusate flow rate was significantly lower in the 24h group (24h 166±45, 12h 266±45, 6h 214±36 mL/min/100g; P=0.008). After reperfusion, levels of urinary neutrophil gelatinase-associated lipocalin (uNGAL), insulin-like growth factor binding protein 7 (IGFBP7) and liver-type fatty acid-binding protein (L-FABP) were similar between groups (P&amp;gt;0.05). Levels of oxygen consumption were significantly lower in 24h kidneys compared to 12h (24h 1.45±0.86, 12h 4.3±1.78 mL/min/100g; P=0.0294). Histological evaluation showed a preserved renal morphology in all kidneys, except for the 24h group which showed a mild increase in tubular and endothelial damage. Conclusion This study demonstrated that human kidneys can be successfully preserved with SNAP for up to 12h. There was some evidence of additional ischaemic injury in the 24h SNAP kidneys which warrants further investigation.

Causal association between cardiovascular proteins and membranous nephropathy: a bidirectional Mendelian randomization.

Multiple circulating proteins have been reported to participate in human diseases. However, the association between cardiovascular proteins and membranous nephropathy (MN) remained profoundly elusive. A bidirectional Mendelian randomization (MR) analysis was conducted to explore the causal correlation between ninety cardiovascular proteins and MN. Genome-wide association study (GWAS) data of cardiovascular proteins and MN were all from European research. Inverse variance weighted (IVW) was used as the main approach. Moreover, MR-Egger, weighted median, weighted mode, and simple mode were also performed. Cochrane's Q test, MR-Egger, and MR-PRESSO were conducted for sensitivity analysis. According to IVW method, fatty acid-binding protein and thrombomodulin (TM) were identified as risk factors for MN, while a protective role was detected in tissue-type plasminogen activator. Additionally, MN was associated with an elevated level of macrophage colony-stimulating factor 1, stem cell factor, TM, and tissue factor. Reversely, MN was also correlated with a downregulated level of beta-nerve growth factor, Cathepsin D, hepatocyte growth factor, interleukin-6 receptor subunit alpha, macrophage colony-stimulating factor 1, and myeloperoxidase. In the sensitivity analysis, no significant pleiotropy and heterogeneity was detected. This was the first study to reveal the causal association between cardiovascular proteins and MN. These specific cardiovascular proteins could be novel biomarkers for MN, and is helpful for timely identify the risk of other diseases that might result from MN. However, further clinical studies are needed to confirm our results.