Plasma Citrulline Research Articles

Evaluation of the role of EGFR exon 19 747-750 deletion mutation and plasma amino acid profile in the development of lung cancer.

Lung cancer (LC) is the most common form of cancer in the world. Of the proteins involved in cell differentiation and proliferation, the epidermal growth factor receptor (EGFR) is among the most significant. Amino acids play a crucial role in cell physiology as metabolic regulators. The benefits of liquid biopsies are their non-invasive nature, ease of collection, and ability to depict the entire tumor's status. The present study is designed to detect the relation between the EGFR exon 19 747-750 deletion mutation and lung cancer and investigate the patterns of alterations of plasma-free amino acids (PFAA) in lung cancer patients of different histopathological types and stages as biomarkers for early detection of lung cancer. The study sample comprised 60 lung cancer patients and 60 age- and sex-matched healthy individuals as the control group. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used to examine the EGFR exon 19 747-750 deletion mutation, and an AA analyzer was used to quantify the plasma free amino acid (PFAA) profile. Compared with controls, LC patients had significantly higher levels of three AAs and significantly lower levels of fifteen AAs. Thirteen AAs varied significantly between stages I and II. In the lung cancer group, the percentage of cases of mutant EGFR exon-19 deletion increased to 30% from 13.3% in the control group. The histological forms of lung cancer did not significantly differ in this rise. Valine and citrulline plasma levels were substantially greater in the mutant than in the wild-type. Lysine, histidine, and methionine were the independent predictors of the LC group in multivariate analysis. Lung cancer development is influenced by the EGFR exon 19 747-750 deletion mutation, and the prognosis and early prediction of lung cancer are greatly affected by the amino acid profile concentrations.

Upregulation of Insulin-like Growth Factor-I in Response to Chemotherapy in Children with Acute Lymphoblastic Leukemia.

The treatment of childhood cancer is challenged by toxic side effects mainly due to chemotherapy-induced organ damage and infections, which are accompanied by severe systemic inflammation. Insulin-like growth factor I (IGF-I) is a key regulating factor in tissue repair. This study investigated associations between the circulating IGF-I levels and chemotherapy-related toxicity in pediatric acute lymphoblastic leukemia (ALL). In this prospective study, we included 114 patients (age: 1-17 years) with newly diagnosed ALL treated according to The Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol between 2013 and 2018. The patients' plasma levels of IGF-I, and the primary binding protein, IGFBP-3, were measured weekly during the first six weeks of treatment, including the induction therapy. The patients' systemic inflammation was monitored by their C-reactive protein (CRP) and interleukin (IL)-6 levels and their intestinal epithelial damage by their plasma citrulline levels. IGF-I and IGFBP-3 were converted into sex-and age-adjusted standard deviation scores (SDS) using 1621 healthy children as reference. At ALL diagnosis, IGF-I levels were decreased (median (quartiles): -1.2 SDS (-1.9 to -0.5), p = 0.001), but increased significantly following the initiation of chemotherapy, peaking on day 8 (0.0 SDS (from -0.8 to 0.7), p < 0.001). This increase correlated with the levels of CRP (rho = 0.37, p < 0.001) and IL-6 (rho = 0.39, p = 0.03) on day 15, when these markers reached maximum levels. A larger IGF-I increase from day 1 to 15 correlated with a slower recovery rate of the intestinal damage marker citrulline from day 15 to 29 (rho = -0.28, p = 0.01). Likewise, IGFBP-3 was reduced at diagnosis, followed by an increase after treatment initiation, and was highly correlated with same-day IGF-I levels. This study demonstrates a chemotherapy-induced increase in IGF-I, with a response that appears to reflect the severity of tissue damage and systemic inflammation, preceding CRP and IL-6 increases. IGF-I may have potential as an early reactive biomarker for acute toxicity in patients with ALL.

P07-12 Impaired renal function is a confounding factor in the use of plasma citrulline as a marker of intestinal toxicity in rodents

P07-12 Impaired renal function is a confounding factor in the use of plasma citrulline as a marker of intestinal toxicity in rodents

The Effects of L-citrulline Supplementation on the Athletic Performance, Physiological and Biochemical Parameters, Antioxidant Capacity, and Blood Amino Acid and Polyamine Levels in Speed-Racing Yili Horses.

The objective of this study was to evaluate the effects of pre-exercise L-citrulline supplementation on the athletic performance of Yili speed-racing horses during a high-intensity exercise. On the 20th day of the experiment, blood samples were collected at 3 h and 6 h post-supplementation to measure the amino acid and polyamine concentrations. On the 38th day of the experiment, the horses participated in a 2000 m speed race, and three distinct blood samples were gathered for assessing blood gases, hematological parameters, the plasma biochemistry, antioxidant parameters, and NO concentrations. The results indicate that the L-citrulline group showed a significant increase in the plasma citrulline and arginine concentrations. Conversely, the concentrations of alanine, serine, and threonine were significantly decreased. The glycine concentration decreased significantly, while there was a trend towards an increase in the glutamine concentration. Additionally, the levels of putrescine and spermidine in the plasma of the L-citrulline group were significantly increased. In terms of exercise performance, L-citrulline can improve the exercise performance of sport horses, significantly reduce the immediate post-race lactate levels in Yili horses, and accelerate the recovery of blood gas levels after an exercise. Furthermore, in the L-citrulline group of Yili horses, The levels of the total protein of plasma, superoxide dismutase, catalase, and lactate dehydrogenase were significantly increased both 2 h before and 2 h after the race. The total antioxidant capacity showed a highly significant increase, while the malondialdehyde content significantly decreased. In the immediate post-race period, the creatinine content in the L-citrulline group significantly increased. In conclusion, this study demonstrates that L-citrulline supplementation can influence the circulating concentrations of L-citrulline and arginine in Yili horses, enhance the antioxidant capacity, reduce lactate levels, and improve physiological and biochemical blood parameters, thereby having a beneficial effect on the exercise performance of athletic horses.

Gut microbiota and intestinal rehabilitation: a prospective childhood cohort longitudinal study of short bowel syndrome (the MIRACLS study): study protocol

IntroductionShort bowel syndrome (SBS) is the predominant cause of paediatric intestinal failure. Although life-saving, parenteral nutrition (PN) is linked to complications and may impact quality of life (QoL). Most children...

Intestinal mucositis, systemic inflammation and bloodstream infections following high-dose methotrexate treatment in childhood acute lymphoblastic leukaemia: Comparison between the NOPHO ALL 2008 protocol and the ALLTogether1 protocol.

Severe intestinal mucositis (IM) increases the risk of bloodstream infections (BSI) and inflammatory toxicity during acute lymphoblastic leukaemia (ALL) induction treatment. However, the implications of IM in subsequent ALL therapy phases after achieving remission remain unknown. This study investigated the relationship between IM (measured by plasma citrulline and the chemokine CCL20) and the development of BSI and systemic inflammation (reflected by C-reactive protein, CRP) in children with ALL during high-dose methotrexate (HDMTX) treatment, an important part of ALL consolidation therapy. The study compared patients treated according to the NOPHO ALL 2008 protocol (n = 52) and the ALLTogether1 protocol (n = 42), both with identical HDMTX procedures but different scheduling. One week post-HDMTX, citrulline dropped to median levels of 14.5 and 16.9 μM for patients treated according to the NOPHO ALL 2008 and ALLTogether1 protocols, respectively (p = 0.11). In a protocol and neutrophil count-adjusted analysis, hypocitrullinaemia (<10 μmol/L) was associated with increased odds of BSI within 3 weeks from HDMTX (OR = 26.2, p = 0.0074). Patients treated according to the NOPHO ALL 2008 protocol exhibited increased mucosal- and systemic inflammation post-HDMTX compared to patients treated according to ALLTogether1, with increased CCL20 (14.6 vs. 3.7 pg/mL, p < 0.0001) and CRP levels (10.0 vs. 1.0 mg/L, p < 0.0001). Both citrulline and CCL20 correlated with CRP for these patients (rs = -0.44, p = 0.0016 and rs = 0.35, p = 0.016, respectively). These results suggest that hypocitrullinaemia following HDMTX increases the risk of BSI, confirming previous observations from more intensive treatments. Moreover, these data indicate that the patients' vulnerability to mucositis and inflammatory toxicity after chemotherapy varies with treatment protocol.

Translating plasma citrulline concentration in clinical practice: Role of cross-sectional assessment in adult patients with short bowel syndrome

BackgroundCross-sectional plasma citrulline concentration (CIT) is considered a marker of enterocyte mass. The role of CIT in clinical practice in patients with short bowel syndrome (SBS) is not clearly defined. AimTo assess the accuracy of CIT to discriminate SBS from healthy controls (HC) and SBS with intestinal failure (SBS-IF), requiring intravenous supplementation (IVS), from SBS with intestinal insufficiency (SBS-II). MethodsCross-sectional study on unselected outpatients (31 SBS-II, 113 SBS-IF) and 19 healthy controls (HC). Demographic data, SBS characteristics, nutritional status, oral intake, intestinal fat absorption, renal function and IF severity, categorized by the volume of the required IVS, were collected at time of CIT evaluation (µmol/L). Data as mean±SD. ResultsCIT was 36.6 ± 6.0 in HC, 30.2 ± 14.0 in SBS-II and 18.8 ± 12.3 in SBS-IF (p < 0.001). CIT cutoff was 31 for the diagnosis of SBS (sensitivity 79 %, specificity 89 %), and 14 for the discrimination between SBS-IF and SBS-II (sensitivity 100 %, specificity 51 %). Wide ranges of CIT were observed in all SBS-IF severity categories. ConclusionsIn unselected SBS patients, CIT was accurate to diagnose SBS, had high sensitivity to diagnose SBS-IF but showed low specificity for SBS-II. In SBS-IF, CIT was not an accurate marker of IF severity.

Dietary protein re-alimentation following restriction improves protein deposition via changing amino acid metabolism and transcriptional profiling of muscle tissue in growing beef bulls

This study aimed to develop a compensatory growth model using growing beef cattle by changing dietary protein and to investigate the underlying mechanisms of compensatory protein deposition in muscle tissue. Twelve Charolais bulls were randomly assigned to one of two groups with two periods: 1) a control group (CON) fed a 13% crude protein (CP) diet for 6 weeks; 2) a treatment group (REC) fed a 7% CP diet for 4 weeks (restriction period) and fed a 13% CP diet in the following 2 weeks (re-alimentation period). Growth performance, digestibility, nitrogen balance, targeted metabolomics of amino acids (AA) in plasma, and transcriptional profiling in muscle tissue were analyzed. Protein restriction decreased average daily gain (ADG; P < 0.05), while protein re-alimentation increased ADG relative to the CON (P < 0.05). Compared to the CON, REC reduced retained N (P < 0.05), and protein re-alimentation increased retained N and N utilization efficiency (P < 0.05), due to reduced urinary urea, hippuric acid, and creatinine excretions (P < 0.05). Ruminal NH3-N in the REC was lower than that in the CON in the protein re-alimentation period (P < 0.05). However, there was no difference in microbial protein and plasma urea nitrogen concentrations. Dietary protein restriction decreased plasma valine and aspartic acid concentrations relative to the CON (P < 0.05), and increased proline and 3-methyl-L-histidine concentrations (P < 0.05). After dietary protein re-alimentation, REC increased plasma citrulline concentrations (P < 0.05). The transcriptional profiling revealed that REC upregulated the AA transporter SLC3A1, and protein re-alimentation downregulated SLC7A8 in the muscle cell membrane. Within the muscle cell, upregulated cytosolic arginine sensor for mTORC1 subunit 2 (CASTOR2) inhibited protein synthesis by inhibiting the mammalian target of rapamycin complex 1 phosphorylation in the protein restriction period, while DNA-damage-inducible transcript 4 (DDIT4) activated the mTOR signaling pathway and promoted protein synthesis in the protein re-alimentation period. In summary, the targeted metabolomics and transcriptomics analyses demonstrated that protein re-alimentation following restriction can promote protein synthesis and reduce muscle breakdown by regulating AA metabolism and functional transcripts related to AA transporters and the mTOR signaling pathway.

Empagliflozin increases plasma levels of citrulline, histidine, and α-aminobutyric acid in patients with type 2 diabetes: effects of a sodium-glucose co-transporter 2 inhibitor on the plasma amino acid profile

ABSTRACT Background To investigate effects of empagliflozin on plasma amino acids in people with type 2 diabetes. Research design and methods In a randomized, active-controlled, open-label trial, 58 patients with type 2 diabetes were randomized to 10 mg/day empagliflozin (n = 29) or standard treatment without empagliflozin (control group, n = 29) and treated for 12 weeks. We obtained blood samples at baseline and 12 weeks and assessed the plasma amino acid profile by liquid chromatography-mass spectrometry liquid chromatography. We also calculated the Fischer ratio (the ratio of branched-chain to aromatic amino acids). Results In the empagliflozin group but not in the control group, plasma levels of citrulline, histidine, and α-aminobutyric acid (AABA), the Fischer ratio, and serum high-molecular weight (HMW) adiponectin increased significantly (p = 0.0099, 0.0277, 0.0318, 0.0135, and 0.0304, respectively) and plasma plasminogen activator inhibitor-1 (PAI-1) decreased significantly (p = 0.0014). In the empagliflozin group, the change in plasma citrulline was positively correlated with the changes in HMW adiponectin (r = 0.488, p = 0.0084) and the Fischer ratio (r = 0.393, p = 0.0353) but negatively correlated with the change in ferritin (r= −0.533,p = 0.0051); the change in plasma histidine was negatively correlated with the change in PAI-1 (r= –0.398, p = 0.0397) and urinary albumin creatinine ratio (r= −0.478, p = 0.0088). Conclusion Empagliflozin significantly increases plasma citrulline, histidine, and AABA in people with type 2 diabetes. Clinical trial registration www.umin.ac.jp identifier is UMIN000025418.

Is plasma citrulline a good marker of hemodynamic status in malnourished patients with anorexia nervosa?

ObjectiveMalnourished patients with anorexia nervosa (AN) have lower plasma citrulline level compared to healthy controls. Citrulline is a non-essential amino-acid synthetized by the enterocyte and has functions affecting cardiovascular status. The aim of the study is to describe citrulline plasma level and to assess its relationship with hemodynamic status in a cohort of malnourished adult patients with AN. MethodsA retrospective observational study including malnourished patients with AN hospitalized between January 2018 and January 2019 for the treatment of severe malnutrition was carried out. Anthropometric measures, biochemical tests, and cardiac function indicators including doppler echocardiographic parameters were evaluated. ResultsForty-eight patients with a median age of 29 [21–35.5] years old and body mass index (BMI) of 12 [10.5–-13.4] kg/m2 were included. Median systolic blood pressure (SBP) and median diastolic blood pressure (DBP) were respectively 99 [90–110] mmHg and 68 [59–73] mmHg. Median left ventricular ejection fraction (LVEF) was at 65 [58–69] %. Plasma citrulline level was under the normal range in 58% of patients and was positively correlated with fat mass, stroke volume, and left ventricular end diastolic volume, but not BMI. ConclusionCitrulline level may be an innovative associated marker of hemodynamic status in malnourished patients with AN. Further research and prospective studies are needed to elucidate the specific pathways involved.

Role of mucositis in predicting gut microbiota composition in people with cancer.

Disruption of the precious ecosystem of micro-organisms that reside in the gut - the gut microbiota - is rapidly emerging as a key driver of the adverse side effects/toxicities caused by numerous anti-cancer agents. Although the contribution of the gut microbiota to these toxicities is understood with ever increasing precision, the cause of microbial disruption (dysbiosis) remains poorly understood. Here, we discuss current evidence on the cause(s) of dysbiosis after cancer therapy, positioning breakdown of the intestinal mucosa (mucositis) as a central cause. Dysbiosis in people with cancer has historically been attributed to extensive antibiotic use. However, evidence now suggests that certain antibiotics have minimal impacts on the microbiota. Indeed, recent evidence shows that the type of cancer therapy predicts microbiota composition independently of antibiotics. Given most anti-cancer drugs have modest effects on microbes directly, this suggests that their impact on the gut microenvironment, in particular the mucosa, which is highly vulnerable to cytotoxicity, is a likely cause of dysbiosis. Here, we outline evidence that support this hypothesis, and discuss the associated clinical implications/opportunities. The concept that mucositis dictates microbiota compositions provides two important implications for clinical practice. Firstly, it reiterates the importance of prioritising the development of novel mucoprotectants that preserve mucosal integrity, and indirectly support microbial stability. Secondly, it provides an opportunity to identify dysbiotic events and associated consequences using readily accessible, minimally invasive biomarkers of mucositis such as plasma citrulline.

The efficacy of Carbamylglutamate impacts the nutritional management of patients with N-Acetylglutamate synthase deficiency

BackgroundThe autosomal recessive disorder N-acetylglutamate synthase (NAGS) deficiency is the rarest defect of the urea cycle, with an incidence of less than one in 2,000,000 live births. Hyperammonemic crises can be avoided in individuals with NAGS deficiency by the administration of carbamylglutamate (also known as carglumic acid), which activates carbamoyl phosphatase synthetase 1 (CPS1). The aim of this case series was to introduce additional cases of NAGS deficiency to the literature as well as to assess the role of nutrition management in conjunction with carbamylglutamate therapy across new and existing cases.MethodsWe conducted retrospective chart reviews of seven cases of NAGS deficiency in the US and Canada, focusing on presentation, diagnosis, medication management, nutrition management, and outcomes.ResultsFive new and two previously published cases were included. Presenting symptoms were consistent with previous reports. Diagnostic confirmation via molecular testing varied in protocol across cases, with consecutive single gene tests leading to long delays in diagnosis in some cases. All patients responded well to carbamylglutamate therapy, as indicated by normalization of plasma ammonia and citrulline, as well as urine orotic acid in patients with abnormal levels at baseline. Although protein restriction was not prescribed in any cases after carbamylglutamate initiation, two patients continued to self-restrict protein intake. One patient experienced two episodes of hyperammonemia that resulted in poor long-term outcomes. Both episodes occurred after a disruption in access to carbamylglutamate, once due to insurance prior authorization requirements and language barriers and once due to seizure activity limiting the family’s ability to administer carbamylglutamate.ConclusionsFollow-up of patients with NAGS deficiency should include plans for illness and for disruption of carbamylglutamate access, including nutrition management strategies such as protein restriction. Carbamylglutamate can help patients with NAGS deficiency to liberalize their diets, but the maximum safe level of protein intake to prevent hyperammonemia is not yet known. Patients using this medication should still monitor their diet closely and be prepared for any disruptions in medication access, which might require immediate dietary adjustments or medical intervention to prevent hyperammonemia.

Intermediate versus morning chronotype has lower vascular insulin sensitivity in adults with obesity.

Chronotype reflects a circadian rhythmicity that regulates endothelial function. While the morning chronotype (MORN) usually has low cardiovascular disease risk, no study has examined insulin action on endothelial function between chronotypes. We hypothesized intermediate chronotypes (INT) would have lower vascular insulin sensitivity than morning chronotype (MORN). Adults with obesity were classified per Morningness-Eveningness Questionnaire (MEQ) as either MORN (n = 27, 22 female, MEQ = 63.7 ± 4.7, 53.8 ± 6.7 years, 35.3 ± 4.9 kg/m2) or INT (n = 29, 23 female, MEQ = 48.8 ± 6.7, 56.6 ± 9.0 years, 35.7 ± 6.1 kg/m2). A 120 min euglycaemic-hyperinsulinaemic clamp (40 mU/m2/min, 90 mg/dl) was conducted to assess macrovascular insulin sensitivity via brachial artery flow-mediated dilation (%FMD; conduit artery), post-ischaemic flow velocity (resistance arteriole), as well as microvascular insulin sensitivity via contrast-enhanced ultrasound [e.g. microvascular blood volume (perfusion)]. Fasting plasma arginine and citrulline, as well as fasting and clamp-derived plasma endothelin-1 and nitrate/nitrite, were assessed as surrogates of vasoconstriction and nitric oxide-mediated vasodilation. Aerobic fitness (VO2max) and body composition (dual-energy X-ray absorptiometry) were also collected. MORN had a higher VO2max compared with INT (p < .01), although there was no difference in fat mass. While fasting FMD was similar between groups, insulin lowered FMD corrected to shear stress and microvascular blood volume in INT compared with MORN after co-varying for VO2max (both p ≤ .02). INT also had a lower fasting nitrate (p = .03) and arginine (p = .07). Higher MEQ correlated with elevated FMD (r = 0.33, p = .03) and lower post-ischaemic flow velocity (r = -0.33, p = .03) as well as shear rate (r = -0.36, p = .02) at 120 min. When measured during the morning, INT had a lower vascular insulin sensitivity than MORN. Additional work is needed to understand endothelial function differences among chronotypes to optimize cardiovascular disease risk reduction.

Correlates of Plasma Citrulline, a Potential Marker of Enterocyte Mass, among Children with Stunting: A Cross-Sectional Study in Uganda

BackgroundEnvironmental enteric dysfunction (EED) is associated with stunting. Citrulline, produced in mature enterocytes, may be a valuable biomarker of small intestinal enterocyte mass in the context of EED. ObjectivesWe aimed to explore the correlates of plasma citrulline (p-cit) in children with stunting. MethodsIn a cross-sectional study using baseline data from the community-based MAGNUS (milk affecting growth, cognition and the gut in child stunting) trial (ISRCTN13093195), we explored potential correlates of p-cit in Ugandan children with stunting aged 12–59 mo. Using linear regression in univariate and multivariate models, we explored associations with socioeconomics, diet, micronutrient status, and water, sanitation, and hygiene characteristics. The influence of covariates age, fasting, and systemic inflammation were also explored. ResultsIn 750 children, the mean ± standard deviation age was 32.0 ± 11.7 mo, and height-for-age z-score was –3.02 ± 0.74. P-cit, available for 730 children, differed according to time fasted and was 20.7 ± 8.9, 22.3 ± 10.6 and 24.2 ± 13.1 μmol/L if fasted <2, 2–5 and >5 h, respectively. Positive correlates of p-cit were age [0.07; 95% confidence interval (CI): 0.001, 0.15 μmol/L] and log10 serum insulin-like growth factor-1 (8.88; 95% CI: 5.09, 12.67 μmol/L). With adjustment for systemic inflammation, the association with serum insulin-like growth factor-1 reduced (4.98; 95% CI: 0.94, 9.03 μmol/L). Negative correlates of p-cit included food insecurity, wet season (–3.12; 95% CI: –4.97, –1.26 μmol/L), serum C-reactive protein (–0.15; 95% CI: –0.20, –0.10 μmol/L), serum α1-acid glycoprotein (–5.34; 95% CI: –6.98, –3.70 μmol/L) and anemia (–1.95; 95% CI: –3.72, –0.18 μmol/L). Among the negatively correlated water, sanitation, and hygiene characteristics was lack of soap for handwashing (–2.53; 95% CI: –4.82, –0.25 μmol/L). Many associations attenuated with adjustment for inflammation. ConclusionsMany of the correlates of p-cit are characteristic of populations with a high EED prevalence. Systemic inflammation is strongly associated with p-cit and is implicated in EED and stunting. Adjustment for systemic inflammation attenuates many associations, reflecting either confounding, mediation, or both. This study highlights the complex interplay between p-cit and systemic inflammation.

Plasma citrulline levels in patients with short Bowel syndrome

Plasma citrulline levels in patients with short Bowel syndrome

Self-emulsifying drug delivery systems (SEDDS) disrupt the gut microbiota and trigger an intestinal inflammatory response in rats

Self-emulsifying drug delivery systems (i.e. SEDDS, SMEDDS and SNEDDS) are widely employed as solubility and bioavailability enhancing formulation strategies for poorly water-soluble drugs. Despite the capacity for SEDDS to effectively facilitate oral drug absorption, tolerability concerns exist due to the capacity for high concentrations of surfactants (typically present within SEDDS) to induce gastrointestinal toxicity and mucosal irritation. With new knowledge surrounding the role of the gut microbiota in modulating intestinal inflammation and mucosal injury, there is a clear need to determine the impact of SEDDS on the gut microbiota. The current study is the first of its kind to demonstrate the detrimental impact of SEDDS on the gut microbiota of Sprague-Dawley rats, following daily oral administration (100 mg/kg) for 21 days. SEDDS comprising a lipid phase (i.e. Type I, II and III formulations according to the Lipid Formulation Classification Scheme) induced significant changes to the composition and diversity of the gut microbiota, evidenced through a reduction in operational taxonomic units (OTUs) and alpha diversity (Shannon’s index), along with statistically significant shifts in beta diversity (according to PERMANOVA of multi-dimensional Bray-Curtis plots). Key signatures of gut microbiota dysbiosis correlated with the increased expression of pro-inflammatory cytokines within the jejunum, while mucosal injury was characterised by significant reductions in plasma citrulline levels, a validated biomarker of enterocyte mass and mucosal barrier integrity. These findings have potential clinical ramifications for chronically administered drugs that are formulated with SEDDS and stresses the need for further studies that investigate dose-dependent effects of SEDDS on the gastrointestinal microenvironment in a clinical setting.

PSV-29 Plasma Citrulline Is Strongly Correlated with Jejunum and Ileum Citrulline Concentrations in Pigs at Weaning

Abstract Pigs at weaning are abruptly exposed to numerous stressors that negatively affect gut health. While the term gut health lacks a clear definition, it is best measured by its key functions, including nutrient digestion, absorption, and metabolism, mucosal immunity, and barrier function. The gut is the main endogenous source of citrulline, a potential biomarker of gut function. The objective of this study was to determine the relationship between plasma and intestinal concentrations of citrulline and citrulline precursors in pigs. Pigs (initial BW = 7,233 ± 683 g) were either weaned at 21 d age and euthanized at 23 d age (W; n = 9) or were not weaned, remained with the sow, and euthanized at 23 d age (NW; n = 9). At euthanasia, blood, jejunum, and ileum tissue was collected and snap-frozen in liquid nitrogen; segments of mid jejunum and distal ileum were collected for morphological analysis. Plasma and tissue glutamine (Gln), glutamate (Glu), proline (Pro), ornithine (Orn), and citrulline (Cit) concentrations were determined by reverse-phase HPLC following pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. Data were analyzed with the generalized linear mixed model and correlation procedures of SAS (version 9.4). Pearson correlation coefficients between 0.50 and 0.69 were considered as moderate, between 0.70 and 0.89 as strong, and between 0.90 to 1 as very strong. Jejunum villus height was reduced in W compared with NW pigs (370 versus 246 ± 18 µm; P &amp;lt; 0.001), whereas ileum villus height was not different between NW and W pigs (257 versus 215 ± 27 µm; P = 0.27). Among precursors for gut Cit synthesis, plasma Pro was strongly correlated with jejunum Pro (r = 0.83; P &amp;lt; 0.001) and very strongly correlated with ileum Pro (r = 0.91; P &amp;lt; 0.001). Plasma Glu was moderately correlated with ileum Glu (r = 0.58; P = 0.014), but not with jejunum Glu (r = 0.18, P = 0.48), whereas plasma Gln was moderately correlated with ileum Gln (r = 0.57; P = 0.016) and strongly correlated with jejunum Gln (r = 0.80; P &amp;lt; 0.001). Plasma Orn was strongly correlated with both jejunum Orn (r = 0.73; P &amp;lt; 0.001) and ileum Orn (r = 0.78; P &amp;lt; 0.001). Plasma Cit was strongly correlated with jejunum Cit (r = 0.77; P &amp;lt; 0.001) and very strongly correlated with ileum Cit (r = 0.95; P &amp;lt; 0.001). Plasma Cit can be used to estimate gut Cit content and may be predictive of gut function in nursery pigs undergoing weaning stress.

Clinical and genetic analysis of 26 Chinese patients with neonatal intrahepatic cholestasis due to citrin deficiency

BackgroundNeonatal intrahepatic cholestasis due to citrin deficiency (NICCD) is an autosomal recessive disorder caused by SLC25A13 genetic mutations. We retrospectively analyzed 26 Chinese infants with NICCD (years 2014-2022) in Quanzhou City. MethodsThe plasma citrulline (CIT) concentration analyzed by tandem mass spectrometry (MS/MS), biochemical parameters and molecular analysis results are presented. ResultsTwelve genotypes were discovered. The relationship between the CIT concentration and genotype is uncertain. In total, 8 mutations were detected, with 4 variations, c.851_854delGTAT, c.615 + 5G > A, c.1638_1660dup and IVS16ins3kb, constituting the high-frequency mutations. Specifically, we demonstrated 2 patients with NICCD combined with another inborn errors of metabolism (IEM). Patient No. 22 possessed compound heterozygous mutations of c.615 + 5G > A and c.790G > A in the SLC25A13 gene accompanied by compound heterozygous variations of c.C259T and c.A155G in the PTS gene. Additionally, Patient No. 26 carried c.51C > G and c.760C > T in the SLC22A5 gene as well as c.615 + 5G > A and IVS16ins3kb in the SLC25A13 gene. ConclusionsWe report a case of the simultaneous occurrence of primary carnitine deficiency (PCD) and NICCD.

Plasma citrulline concentration and plasma LPS detection among critically ill patients a prospective observational study

PurposeGut can be a source of sepsis but sepsis itself can induce gut dysfunction. We aimed to study whether plasma citrulline, a marker of enterocyte mass, was correlated with plasma lipopolysaccharide, a potential marker of bacterial translocation among critically ill patients. Materials and methodsCritically ill patients admitted to the ICU. Plasma citrulline and plasma LPS concentration and activity were measured at ICU admission. Patients were compared according to the presence of sepsis at ICU admission. Results109 critically ill patients, with SOFA score 8 [6–12], were prospectively included. Sixty six patients (61%) had sepsis at ICU admission. There was no correlation between plasma citrulline concentration and plasma LPS concentration or activity. However, sepsis at ICU admission was associated with a lower plasma citrulline concentration (13.4 μmol.L−1 vs 21.3 μmol.L−1, p = 0.02). Plasma LPS activity was significantly higher among patients with abdominal sepsis compared to patients with extra-abdominal sepsis (1.04 EU/mL vs 0.63, p = 0.01). ConclusionsPlasma citrulline is not associated with the level of plasma LPS but is strongly decreased among septic patients. Detection of LPS is ubiquitous among critically ill patients but abdominal sepsis is associated with increased plasma LPS activity compared to extra-abdominal sepsis.

Enteral L-citrulline supplementation in preterm infants is safe and effective in increasing plasma arginine and citrulline levels-a pilot randomized trial.

Deficiencies of citrulline and arginine have been associated with adverse outcomes in preterm-infants and data regarding enteral supplementation in preterm infants is limited. This randomized -trial [NCT03649932] included 42 preterm infants (gestational age ≤33 weeks) randomized to receive enteral L-citrulline in low (100 mg/kg/day), medium (200 mg/kg/day) and high-dose (300 mg/kg/day) groups for 7 days. Plasma citrulline and arginine levels were obtained pre-and-post supplementation and efficacy was determined by a significant increase in levels after supplementation. A p < 0.05 was considered significant. Safety monitoring included blood-pressure-monitoring as well as complications and death during hospitalization. A total of 40/42 (95%) of the recruits completed the 7-day supplementation with no adverse events. Plasma-citrulline levels increased significantly in all three groups while plasma-arginine levels increased significantly in the high-dose group. Enteral L-citrulline supplementation in preterm infants is safe and effective in increasing plasma citrulline and arginine levels. NCT03649932 https://clinicaltrials.gov/ct2/show/NCT03649932 .