Efficacy of serum leucine-rich alpha-2 glycoprotein in predicting findings of Crohn's disease small bowel lesion in capsule endoscopy.

Background/Aims: Small bowel capsule endoscopy (SBCE) is an evaluation method for small bowel (SB) lesions in Crohn's disease (CD). However, the relationship between SBCE findings and the serological biomarker leucine-rich alpha-2 glycoprotein (LRG) remains unclear. We aimed to establish appropriate cutoff values of LRG to predict the presence of SB lesions in CD through SBCE. Methods: Patients with CD with SB lesions who had undergone SBCE and LRG measurements 1 month before and after the SBCE were included. The LRG values for ulcers ≥0.5 cm and other inflammatory lesions noted in SBCE were determined using the Youden Index, and the sensitivity and specificity were calculated. Additionally, the correlation between the SBCE scores (CD Activity in Capsule Endoscopy) and LRG values was evaluated. Results: Forty patients without active colorectal lesions were included in the study. When the cutoff value of LRG for SB ulcers ≥ 0.5 cm was set at 14 µg/mL, the sensitivity was 92.3%, specificity was 81.5%, positive predictive value (PPV) was 70.6%, and negative predictive value (NPV) was 95.7%. In contrast, an LRG cutoff value of 12 µg/mL without inflammatory findings had a sensitivity of 91.7%, specificity of 82.1%, PPV of 68.8%, and NPV of 95.8%. CD Activity in Capsule Endoscopy correlated well with LRG values (Spearman's rank correlation coefficient ρ = 0.681, P< 0.001). Conclusions: An LRG cutoff value of 14 µg/mL may be useful in predicting the presence of SB ulcers ≥ 0.5 cm, and an LRG cutoff value of 12 µg/mL may be useful in predicting the absence of SB inflammatory findings.

Increased level of serum leucine-rich-alpha-2-glycoprotein 1 in patients with clear cell renal cell carcinoma.

BACKGROUND: Currently, no useful serum markers exist for clear cell renal cell carcinoma (ccRCC), making early detection challenging as diagnosis relies solely on imaging tests. Radiation exposure is also a concern due to multiple required CT examinations during treatment. Renal cell carcinoma (RCC) histological types include ccRCC and non-clear cell RCC (non-ccRCC); however, treatment response to medications varies which necessitates accurate differentiation between the two. Therefore, we aimed to identify a novel serum marker of RCC. Increased LRG1 expression in the serum has been demonstrated in multiple cancer types. However, the expression of LRG1 expression in the serum and cancer tissues of patients with RCC has not been reported. Since ccRCC is a hypervascular tumor and LRG1 is capable of accelerating angiogenesis, we hypothesized that the LRG1 levels may be related to ccRCC. Therefore, we examined LRG1 expression in sera from patients with RCC. METHODS: Using an enzyme-linked immunosorbent assay, serum levels of leucine-rich-alpha-2-glycoprotein 1 (LRG1) were measured in 64 patients with ccRCC and 22 patients non-ccRCC who underwent radical or partial nephrectomy, as well as in 63 patients without cancer. RESULTS: Median values of serum LRG1 and their inter-quartile ranges were 63.2 (42.8-94.2) µg/mL in ccRCC, 23.4 (17.7-29.6) µg/mL in non-ccRCC, and 36.0 (23.7-56.7) µg/mL in patients without cancer, respectively (ccRCC vs. non-ccRCC or patients without cancer: P < 0.001). C-reactive protein (CRP) levels (P = 0.002), anemia (P = 0.037), hypercalcemia (P = 0.023), and grade (P = 0.031) were independent predictors of serum LRG1 levels in ccRCC. To assess diagnostic performance, the area under the receiver operating characteristic curve of serum LRG1 was utilized to differentiate ccRCC from non-cancer and non-ccRCC, with values of 0.73 (95% CI, 0.64-0.82) and 0.91 (95% CI, 0.82-0.96), respectively. CONCLUSIONS: LRG1 served as a serum marker associated with inflammation, indicated by CRP, anemia, hypercalcemia, and malignant potential in ccRCC. Clinically, serum LRG1 levels may assist in differentiating ccRCC from non-ccRCC with excellent diagnostic accuracy.

Leucine-rich alpha-2-glycoprotein 1 affects bone destruction via IL-6 in mouse periodontitis model.

OBJECTIVE: To investigate the production of leucine-rich α-2-glycoprotein-1 (LRG1) in periodontitis patients and its effectiveness as a new diagnostic marker for periodontitis. SUBJECTS AND METHODS: In vitro experiments were conducted to analyze LRG1 mRNA expression in human gingival epithelial cells and fibroblasts via quantitative real-time PCR. In vivo experiments were conducted to analyze LRG1 localization in periodontitis patients. The correlation between the serum LRG1 levels and alveolar bone resorption in the mouse periodontitis model was also investigated. RESULTS: A positive correlation existed between the periodontal inflamed surface area and serum LRG1 levels (Spearman's rank correlation coefficient: 0.60). LRG1 mRNA expression in human gingival epithelial cells and fibroblasts was upregulated by Porphyromonas gingivalis stimulation or tumor necrosis factor-α stimulation. Interleukin-6 in human gingival epithelial cells and fibroblasts induced the production of LRG1 and transforming growth factor-ß. LRG1 levels in the periodontal tissue and serum in the periodontitis model were higher than those in control mice. LRG1 local administration resulted in alveolar bone resorption, whereas the administration of interleukin-6R antibody inhibited bone resorption. CONCLUSIONS: LRG1 levels in serum and periodontal tissue are upregulated in periodontitis and are implicated in periodontal tissue destruction through interleukin-6 production.

Prognostic potency of plasma LRG1 measurement at multiple time points in acute ischemic stroke patients.

Objective: This study aimed to investigate the prognostic potency of LRG1 in acute ischemic stroke (AIS) patients. Methods: Plasma LRG1 levels were detected at admission and on days 3, 7 and 30 in 150 AIS patients. Results: LRG1 positively correlated with total cholesterol (p = 0.016), triglycerides (p = 0.046), C-reactive protein (p < 0.001), TNF-α (p = 0.001) and IL-6 (p = 0.004). After admission, LRG1 showed a decreasing trend (p < 0.001). Interestingly, LRG1 levels at admission (p = 0.014), day 3 (p = 0.027), day 7 (p = 0.008) and day 30 (p = 0.002) were higher in patients with modified Rankin scale score ≥2 versus those with scores <2. The LRG1 levels at day 7 (p = 0.032) and day 30 (p = 0.023) were higher in patients with recurrence versus no recurrence. Conclusion: LRG1 correlates with blood lipids, inflammation and short-term prognosis of AIS.

Relation between LRG1 and CD4+ T cells, cognitive impairment and neurological function in patients with acute ischemic stroke.

Objective: To assess the relationship between LRG1 and CD4+ T cells, cognitive impairment and neurological function in acute ischemic stroke (AIS). Methods: Plasma LRG1 was detected by ELISA in 175 patients with AIS at baseline, day (D) 1, D7, month (M) 1 and M3. Results: LRG1 was negatively related to Th2 and Treg cells and positively linked to Th17 (all p < 0.05). LRG1 increased from baseline to D1, then decreased until M3 (p < 0.001). LRG1 at each assessment point was increased in patients with cognitive impairment or poor neurological function at M3 versus those without (all p < 0.05). Conclusion: LRG1 is linked to decreased Th2 and Tregs, increased Th17, cognitive impairment and nonideal neurological function recovery in patients with AIS.

Significance of Serum Leucine-rich Alpha-2 Glycoprotein as a Diagnostic Marker in Pediatric Inflammatory Bowel Disease.

Serum leucine-rich alpha-2 glycoprotein (LRG) has been utilized for adult inflammatory bowel disease (IBD); however, its efficacy in pediatric IBD remains unknown. The aim of this study was to compare the diagnostic accuracy of serum LRG for pediatric IBD with that of current inflammatory markers, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). This retrospective case-control study included pediatric patients, aged <16 years, who underwent colonoscopy and/or esophagogastroduodenoscopy between April 2017 and March 2022. All eligible patients were divided into two groups: patients with IBD, diagnosed with ulcerative colitis and Crohn's disease, and non-IBD controls. The optimal cut-off value of serum LRG for IBD diagnosis was determined from receiver operating characteristic analysis, and diagnostic accuracy of serum LRG was compared to serum ESR and CRP. A total of 53 patients (24 with IBD and 29 non-IBD controls) met the inclusion criteria. The cut-off value of serum LRG for IBD diagnosis was determined to be 19.5 µg/ml. At this cut-off value, serum LRG had a positive predictive value (PPV) of 0.80 and negative predictive value (NPV) of 0.88. In contrast, PPV and NPV were 0.78 and 0.70 for serum ESR and 0.82 and 0.72 for serum CRP, respectively. Serum LRG can be a potential diagnostic marker for pediatric IBD, with higher diagnostic accuracy than that of the conventional serum markers ESR and CRP.

Systemic interrogation of immune-oncology-related proteins in patients with locally advanced prostate cancer undergoing androgen deprivation and intensity-modulated radiotherapy.

PURPOSE: The primary objective was to establish whether blood-based leucine-rich alpha-2-glycoprotein (LRG1) can predict outcomes in patients with locally advanced prostate cancer undergoing androgen-deprivation therapy (ADT) and radiotherapy (RT) and to determine how it may relate to 92 immune-oncology (I-O)-related proteins in this setting. METHODS: Baseline blood level of LRG1 from patients treated with ADT and RT enrolled in the CuPCa (n = 128) and IMRT (n = 81) studies was measured using ELISA. A longitudinal cohort with matched blood samples from start of ADT, start of RT, and end of RT protocol from 47 patients from the IMRT cohort was used to establish levels of I-O proteins by high-multiplexing Proximal Extension Assay by Olink Proteomics. Statistical analyses using Kaplan-Meier, Cox regression, and LIMMA analyses were applied to predict the prognostic value of LRG1 and its correlation to I-O proteins. RESULTS: High baseline levels of LRG1 predicted a low frequency of treatment failure in patients undergoing ADT + RT in both the CuPCa and the IMRT cohorts. LRG1 was moderately correlated with CD4, IL6, and CSF1. We identified I-O proteins predicting metastatic failure (MF) at different timepoints. CONCLUSION: LRG1 biomarker is associated with I-O proteins and can be used to improve stratification and monitoring of prostate cancer patients undergoing ADT + RT. This work will require further in-depth analyses in independent cohorts with treatment outcome data.

Combination of leucine-rich alpha-2 glycoprotein and fecal markers detect Crohn's disease activity confirmed by balloon-assisted enteroscopy.

BACKGROUND/AIMS: Endoscopic activity confirmed by enteroscopy is associated with poor clinical outcome in Crohn's disease (CD). We investigated which of the existing biomarkers best reflects endoscopic activity in CD patients including the small bowel, and whether their combined use can improve accuracy. METHODS: One hundred and four consecutive patients with ileal and ileocolonic type CD who underwent balloon-assisted enteroscopy (BAE) from October 2021 to August 2022 were enrolled, with clinical and laboratory data prospectively collected and analyzed. RESULTS: Hemoglobin, platelet count, C-reactive protein, leucine-rich alpha-2 glycoprotein (LRG), fecal calprotectin, and fecal hemoglobin all showed significant difference in those with ulcers found on BAE. LRG and fecal calprotectin showed the highest areas under the curve (0.841 and 0.853) for detecting ulcers. LRG showed a sensitivity of 78% and specificity of 80% at a cutoff value of 13 µg/mL, whereas fecal calprotectin showed a sensitivity of 91% and specificity of 67% at a cutoff value of 151 µg/g. Dual positivity for LRG and fecal calprotectin, as well as LRG and fecal hemoglobin, both predicted ulcers with an improved specificity of 92% and 100%. A positive LRG or fecal calprotectin/hemoglobin showed an improved sensitivity of 96% and 91%. Positivity for LRG and either of the fecal biomarkers was associated with increased risk of hospitalization, surgery, and relapse. CONCLUSIONS: The biomarkers LRG, fecal calprotectin, and fecal hemoglobin can serve as noninvasive and accurate tools for assessing activity in CD patients confirmed by BAE, especially when used in combination.

The evaluation of salivary leucine-rich alpha-2 glycoprotein (LRG) and C-reactive protein (CRP) in humans with periodontal health or periodontal disease.

OBJECTIVE: The purpose of the present research is to evaluate the salivary levels of leucine-rich alpha-2 glycoprotein (LRG) and C-reactive protein (CRP) in periodontal health and disease (gingivitis and stage III periodontitis) and also to compare the discriminative efficiencies of both biomarkers in periodontal disease. BACKGROUND: LRG is a new acute-phase protein whose functions are still being investigated. LRG and CRP are both biomarkers that are increased by inflammation. No clinical study has yet investigated the comparison of the level of LRG and CRP in periodontal health, gingivitis and periodontitis in saliva samples. METHODS: A total of 60 individuals, including 20 periodontally healthy (control group/group C), 20 with gingivitis (group G), and 20 with Stage III periodontitis (group P), who were systemically healthy and non-smokers, participated in this study. Periodontal charts were used for recording clinical periodontal parameters and saliva LRG and CRP levels were measured by ELISA. Analyzing the area under the curve (AUC) was performed by the receiver-operating characteristics curve. RESULTS: Salivary levels of LRG and CRP were significantly higher in disease groups than in group C (p < .05). Positive statistically significant correlations were observed between both biomarkers and clinical parameters (p < .05). There was also a strong positive correlation between two biomarkers (p < .05). In distinguishing periodontal disease from periodontal health, LRG (AUC = 0.833) and CRP (AUC = 0.826) were found to have similar accuracy (p = .923). CONCLUSION: LRG and CRP may be useful and similarly effective biomarkers in the diagnosis of periodontal diseases based on the findings of this study.

Appropriate leucine-rich α-2 glycoprotein cut-off value for Japanese patients with ulcerative colitis.

BACKGROUND: It has been suggested that serum leucine-rich α-2 glycoprotein (LRG) could be a novel monitoring biomarker for the assessment of disease activity in inflammatory bowel disease. In particular, the relationship between LRG levels and the endoscopically assessed activity of ulcerative colitis (UC) has become a matter of interest. AIM: To clarify appropriate LRG cut-off values for the prediction of endoscopic and histologic remission in Japanese patients with UC. METHODS: This was a cross-sectional, single-center, observational study of Japanese patients with UC. Among 213 patients with UC, in whom LRG was measured from September 2020 to February 2022, we recruited 30 patients for whom a total colonoscopy and measurements of LRG and C-reactive protein (CRP) were performed on the same day. We retrospectively analyzed correlations between the LRG and CRP levels and endoscopic indices, including the Mayo endoscopic subscore and UC endoscopic index of severity. RESULTS: Correlations between the LRG values and the Mayo endoscopic subscore or UC endoscopic index of severity were significant (r = 0.754, P < 0.0001; r = 0.778, P < 0.0001, respectively). There were also significant correlations between CRP levels and Mayo endoscopic subscore or UC endoscopic index of severity (r = 0.599, P = 0.0005; r = 0.563, P = 0.0012, respectively), although the correlation coefficients were higher for LRG. The LRG cut-off value for predicting endoscopic remission was 13.4 µg/mL for a Mayo endoscopic subscore of 0 [area under the curve (AUC): 0.871; 95% confidence interval (CI): 0.744-0.998], and 13.4 µg/mL for an UC endoscopic index of severity of 0 or 1 (AUC: 0.904; 95%CI: 0.792-1.000). CONCLUSION: LRG may be a surrogate marker for endoscopic activity in UC, with a cut-off value of around 13.4 µg/mL for endoscopically inactive disease.

Novel Utility of Leucine-Rich Alpha-2-Glycoprotein as a Biomarker in Ulcerative Colitis: A Predictor of Endoscopic Remission Independent of Symptoms.

Introduction: Leucine-rich alpha-2-glycoprotein (LRG) is a potential biomarker for disease activity and reflects mucosal healing in patients with ulcerative colitis (UC). However, only a few studies have described a detailed sensitivity analysis of LRG in predicting mucosal healing in patients. This study aimed to evaluate the association between LRG and the endoscopic activity of UC and its predictability for mucosal healing and explore the utility and clinical application of LRG. Methods: The diagnostic accuracy of biomarkers, including LRG, in predicting the endoscopic activity of UC was evaluated. All consecutive patients who underwent total colonoscopy between April 2021 and September 2022 were included. The Mayo endoscopic subscore (MES) was used for assessing endoscopic activity. Furthermore, endoscopic remission was defined as an MES of ≤1. Clinical activity was evaluated based on stool frequency and bloody stool. Receiver operating characteristic curve analysis and binary logistic regression were performed to assess the diagnostic accuracy of the biomarkers. We evaluated LRG trends and treatment response in patients with MES ≥2 who underwent induction therapy. Results: This study comprised 214 patients. The proportions of endoscopically and clinically active patients were 33.6% and 49.1%, respectively. LRG had an area under the curve (AUC) of 0.856, with a higher diagnostic accuracy than other biomarkers, such as C-reactive protein, leukocyte, neutrophil, platelet, and albumin. The cutoff value for LRG was 15.6 µg/mL (sensitivity, 72.2%; specificity, 86.6%). Using the MES, patients with higher scores had higher LRG levels than those with lower scores. The cutoff value, AUC, sensitivity, and specificity varied with a higher AUC for left-sided colitis and pancolitis than for proctitis. Logistic regression analysis showed that LRG was an independent predictor of endoscopic remission using multivariate analysis, even with the factor of clinical activity. The change ratio of LRG pre- and post-treatment was statistically significant in the higher LRG group. Conclusion: LRG reflected endoscopic activity independently, regardless of clinical symptoms. An LRG below the cutoff value could indicate a significantly low probability of endoscopic activity in asymptomatic patients, and follow-up endoscopy (not for cancer screening) may be unnecessary. Furthermore, a higher LRG level might be more useful as an indicator of treatment efficacy.

Biomarkers for Monitoring of Changes in Disease Activity in Ulcerative Colitis.

BACKGROUND: In recent years, various biomarkers of ulcerative colitis (UC) have emerged; however, few studies have simultaneously examined the utility of multiple biomarkers for monitoring disease activity. Additionally, serum leucine-rich alpha-2 glycoprotein (LRG), a new biomarker, may show a blunt response to anti-TNF antibody therapy. This prospective study explored effective biomarkers that could monitor disease activity changes in patients with UC. In addition, we examined the effect of anti-TNF antibody therapy on changes in LRG. METHODS: Blood and stool samples were collected twice from patients with UC: at baseline and at least 8 weeks later. Changes in serum LRG, interleukin (IL)-6, prealbumin (pre-Alb), high-sensitivity C-reactive protein (hs-CRP), CRP, and fecal calprotectin (FC) were measured and correlated with changes in disease activity. The relationship between anti-TNF antibody therapy and LRG levels was also examined in patients with the same disease activity. RESULTS: Forty-eight patients with UC (96 samples) were analyzed. ΔLRG and ΔIL-6 correlated strongly with the change in the partial Mayo (pMayo) score between the two time points (ΔpMayo) (r = 0.686, 0.635, respectively). In contrast, FC and IL-6 were particularly accurate predictors of clinical remission, and their area under the curves (AUCs) were significantly higher than that of CRP (AUC: 0.81, 0.76 vs. 0.50; p = 0.001, 0.005). No association was found between the administration of anti-TNF antibody preparations and the LRG values. CONCLUSIONS: Correlations were found between changes in UC disease activity and LRG, IL-6, pre-Alb, hs-CRP, CRP, and FC. LRG reflects disease activity during anti-TNF antibody therapy.

Usefulness of Serum Leucine-Rich Alpha-2 Glycoprotein as a Surrogate Marker of Small Bowel Mucosal Injury in Crohn's Disease.

Introduction: Although the importance of mucosal healing has been suggested in Crohn's disease, it is difficult to repeat endoscopy, especially for the entire small bowel. Recently, serum leucine-rich alpha-2 glycoprotein (LRG) has been used as a surrogate marker of endoscopy. However, few studies have investigated a correlation between LRG and mucosal injury of the entire small bowel. Methods: We retrospectively analyzed the clinical data of 30 patients with Crohn's disease from June 2020 to August 2022 at Yamaguchi Red Cross Hospital. All the patients were surveyed through the gastrointestinal tract by esophagogastroduodenoscopy, total colonoscopy, and capsule endoscopy (CE). Subjects with mucosal injury only in the small bowel were selected. Then, we assessed the relationship between serum biomarkers (LRG, C-reactive protein [CRP], hemoglobin, albumin) and small bowel mucosal injury scores (Lewis score [LS], Capsule Endoscopy Crohn's Disease Activity Index [CECDAI], and Crohn's Disease Activity in Capsule Endoscopy [CDACE]) calculated by CE. Results: LRG and CRP were significantly correlated with small bowel mucosal injury scores (LS, CECDAI, CDACE) (p < 0.05, Spearman's rank correlation coefficient). The degree of correlation was greater for LRG than for CRP. Conclusions: LRG is a useful surrogate marker that closely reflects small bowel mucosal injury in the entire small bowel.

Monitoring of leucine-rich alpha-2-glycoprotein and assessment by small bowel capsule endoscopy are prognostic for Crohn's disease patients.

Background and Aim: Endoscopy is important to determine the effectiveness of treatment for Crohn's disease (CD), but searching the entire small intestine is difficult. Thus, we investigated the usefulness of leucine-rich alpha-2 glycoprotein (LRG), a new biomarker for predicting mucosal activity, in evaluating the activity of CD small intestinal lesions. This will further determine whether the results of small bowel capsule endoscopy (SBCE) affect the prognosis of patients with CD. Methods: A total of 114 patients with CD who underwent SBCE were included. We analyzed the correlation between LRG and Capsule Endoscopy Crohn's Disease Activity Index (CECDAI). The cutoff value of LRG to achieve mucosal healing was calculated using the receiver operating characteristic curve. Then, we compared the presence or absence of intervention and the relapse rate of patients who could not achieve mucosal healing. Results: The CECDAI correlated with LRG. The calculated LRG value for achieving mucosal healing was ≤11.9. Ninety-one patients were in clinical remission at the time of SBCE. During the follow-up period, 17 patients relapsed. As a result of SBCE, when no treatment intervention was performed in the case of CECDAI ≥3.5, the relapse rate was significantly higher than when CECDAI <3.5 or intervention was performed in the case of CECDAI ≥3.5. Conclusions: The results reveal that LRG correlates with the activity of the entire small intestine and that SBCE assessment and therapeutic intervention can influence patient prognosis.

Serum leucine-rich alpha-2 glycoprotein in monitoring disease activity and intestinal mucosal healing for biotherapy-naïve cases with ulcerative colitis.

Background and Aim: Serum leucine-rich alpha-2 glycoprotein level has been reported to be a useful biomarker in assessing mucosal healing in patients undergoing biotherapy, where mucosal lesions caused by ulcerative colitis are difficult to assess endoscopically. However, no such reports have been reported in biotherapy-naïve cases. Methods: Sixty-eight patients with ulcerative colitis (UC) who were biotherapy-naïve at Kindai University Hospital between October 2021 and October 2022 were enrolled. We prospectively examined the correlation between leucine-rich alpha-2 glycoprotein (LRG), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and Geboes scores with clinical endoscopic activity using the Mayo endoscopic subscore (MES). Results: Mucosal healing was achieved in 39 (57%) patients. Univariate analysis revealed that the factors associated with mucosal healing were LRG (P = 0.0024), CRP (P = 0.1078), ESR (P = 0.0372), and Geboes scores (P = 0.0075). Logistic regression analysis identified LRG and Geboes scores as independent factors associated with mucosal healing assessed using MES (P = 0.0431 for LRG and P = 0.0166 for Geboes scores). Conclusion: LRG was found to be the easiest marker to monitor disease activity and mucosal inflammation in UC patients with biotherapy-naïve cases, with a performance equivalent to that of Geboes scores.

Expression of LRG-1 in mice with hypertensive renal damage and its significance. / LRG-1åœ¨é«˜è¡€åŽ‹è‚¾æŸå®³å°é¼ ä¸­çš„è¡¨è¾¾åŠå ¶æ„ä¹‰.

OBJECTIVES: Long-term elevated blood pressure may lead to kidney damage, yet the pathogenesis of hypertensive kidney damage is still unclear. This study aims to explore the role and significance of leucine-rich alpha-2-glycoprotein-1 (LRG-1) in hypertensive renal damage through detecting the levels of LRG-1 in the serum and kidney of mice with hypertensive renal damage and its relationship with related indexes. METHODS: C57BL/6 mice were used in this study and randomly divided into a control group, an angiotensin II (Ang II) group, and an Ang II+irbesartan group. The control group was gavaged with physiological saline. The Ang II group was pumped subcutaneously at a rate of 1.5 mg/(kg·d) for 28 days to establish the hypertensive renal damage model in mice, and then gavaged with equivalent physiological saline. The Ang II+irbesartan group used the same method to establish the hypertensive renal damage model, and then was gavaged with irbesartan. Immunohistochemistry and Western blotting were used to detect the expression of LRG-1 and fibrosis-related indicators (collagen I and fibronectin) in renal tissues. ELISA was used to evaluate the level of serum LRG-1 and inflammatory cytokines in mice. The urinary protein-creatinine ratio and renal function were determined, and correlation analysis was conducted. RESULTS: Compared with the control group, the levels of serum LRG-1, the expression of LRG-1 protein, collagen I, and fibronectin in kidney in the Ang II group were increased (all P<0.01). After treating with irbesartan, renal damage of hypertensive mice was alleviated, while the levels of LRG-1 in serum and kidney were decreased, and the expression of collagen I and fibronectin was down-regulated (all P<0.01). Correlation analysis showed that the level of serum LRG-1 was positively correlated with urinary protein-creatinine ratio, blood urea nitrogen, and blood creatinine level in hypertensive kidney damage mice. Serum level of LRG-1 was also positively correlated with serum inflammatory factors including TNF-α, IL-1ß, and IL-6. CONCLUSIONS: Hypertensive renal damage mice display elevated expression of LRG-1 in serum and kidney, and irbesartan can reduce the expression of LRG-1 while alleviating renal damage. The level of serum LRG-1 is positively correlated with the degree of hypertensive renal damage, suggesting that it may participate in the occurrence and development of hypertensive renal damage.

Optimal Use of Serum Leucine-Rich Alpha-2 Glycoprotein as a Biomarker for Small Bowel Lesions of Crohn's Disease.

Introduction: A large proportion of small bowel lesions in Crohn's disease (CD) may exist beyond the reach of ileocolonoscopy and there is no gold standard imaging modality to screen them, suggesting the need for optimal biomarkers. We aimed to compare the usefulness of C-reactive protein (CRP), faecal calprotectin (FC), and leucine-rich alpha-2 glycoprotein (LRG) in determining small bowel lesions of CD. Methods: This was a cross-sectional observational study. CRP, FC, and LRG were prospectively measured in patients with quiescent CD who underwent imaging examinations (capsule or balloon-assisted endoscopy, magnetic resonance enterography, or intestinal ultrasound) selected by the physician in clinical practice. Mucosal healing (MH) of the small bowel was defined as a lack of ulcers. Patients with a CD activity index >150 and active colonic lesions were excluded. Results: A total of 65 patients (27, MH; 38, small bowel inflammation) were analysed. The area under the curve (AUC) of CRP, FC, and LRG was 0.74 (95% confidence interval: 0.61-0.87), 0.69 (0.52-0.81), and 0.77 (0.59-0.85), respectively. The AUC of FC and LRG in a subgroup of 61 patients with CRP <3 mg/L (26, MH; 32, small bowel inflammation) was 0.68 (0.50-0.81) and 0.74 (0.54-0.84), respectively. The cut-off of 16 µg/mL of LRG showed the highest positive predictive value of 1.00 with specificity of 1.00, while negative predictive value was highest (0.71) with sensitivity of 0.89 at the cut-off of 9 µg/mL. Conclusion: LRG can accurately detect and/or exclude the small bowel lesions with two cut-off values.

Usefulness of Serum Leucine-rich Alpha 2 Glycoprotein in Crohn's Disease: Is There Any Difference between Small Intestine and Colonic Lesions?

Background: The usefulness of leucine-rich alpha 2 glycoprotein (LRG) to evaluate Crohn's disease (CD) activity differs among various intestinal lesions. We aimed to evaluate the association between endoscopic disease activity based on the Simple Endoscopic Score for Crohn's disease (SES-CD) and LRG level separately for small intestinal and colonic lesions. Methods: We examined the correlation between LRG level and SES-CD and performed receiver operating characteristic (ROC) analysis to determine the LRG cutoff value in 141 patients who underwent endoscopy (total 235 measurements). Furthermore, the LRG cutoff value was analyzed by comparing small intestinal and colonic lesions. Results: LRG levels were significantly higher in patients without mucosal healing than in those with mucosal healing (15.9 µg/mL vs 10.5 µg/mL, P < .0001). The LRG cutoff value for mucosal healing was 14.3 µg/mL (area under the ROC curve [AUC]: 0.80; sensitivity: 0.89; specificity: 0.63). The LRG cutoff value for patients with type L1 was 14.3 µg/mL (sensitivity: 0.91; specificity: 0.53), and that for patients with type L2 was 14.0 µg/mL (sensitivity: 0.95; specificity: 0.73). The diagnostic performance (AUC) of LRG and C-reactive protein (CRP) for mucosal healing was, respectively, 0.75 and 0.60 (P = 0.01) in patients with type L1 and 0.80 and 0.85 (P = 0.90) in patients with type L2. Conclusions: The optimal LRG cutoff value for evaluating mucosal healing in CD is 14.3 µg/mL. LRG is more useful than CRP for predicting mucosal healing in patients with type L1. The superiority of LRG to CRP differs between small intestinal and colonic lesions.

Leucine-Rich Alpha-2-Glycoprotein as a non-invasive biomarker for pediatric acute appendicitis: a systematic review and meta-analysis.

The aim of this study was to analyze the diagnostic performance of Leucine-Rich Alpha-2-Glycoprotein (LRG1) in pediatric acute appendicitis (PAA). We conducted a systematic review of the literature in the main databases of medical bibliography. Two independent reviewers selected the articles and extracted relevant data. Methodological quality was assessed using the QUADAS2 index. A synthesis of the results, standardization of the metrics and 4 random-effect meta-analyses were performed. Eight studies with data from 712 participants (305 patients with confirmed diagnosis of PAA and 407 controls) were included in this review. The random-effect meta-analysis of serum LRG1 (PAA vs control) resulted in a significant mean difference (95% CI) of 46.76 µg/mL (29.26-64.26). The random-effect meta-analysis for unadjusted urinary LRG1 (PAA vs control) resulted in a significant mean difference (95% CI) of 0.61 µg/mL (0.30-0.93). The random-effect meta-analysis (PAA vs control) for urinary LRG1 adjusted for urinary creatinine resulted in a significant mean difference (95% CI) of 0.89 g/mol (0.11-1.66).   Conlusion: Urinary LRG1 emerges as a potential non-invasive biomarker for the diagnosis of PAA. On the other hand, due to the high between-study heterogeneity, the results on serum LRG1 should be interpreted with caution. The only study that analyzed salivary LRG1 showed promising results. Further prospective studies are needed to confirm these findings. What is Known: • Pediatric acute appendicitis continues to be a pathology with a high rate of diagnostic error. • Invasive tests, although useful, are a source of stress for patients and their parents. What is New: • LRG1 emerges as a promising urinary and salivary biomarker for the noninvasive diagnosis of pediatric acute appendicitis.

Serum leucine-rich alpha-2 glycoprotein and calprotectin in children with inflammatory bowel disease: A multicenter study in Japan.

BACKGROUND AND AIM: Serum leucine-rich alpha-2 glycoprotein (LRG) and calprotectin have been studied as disease activity markers in adults with inflammatory bowel disease (IBD). We evaluated them in pediatric IBD patients. METHODS: Subjects under 17 years old undergoing care at 11 Japanese pediatric centers were retrospectively assigned to 3 groups representing Crohn's disease (CD), ulcerative colitis (UC), and normal controls (NC) with irritable bowel syndrome or no illness. Serum LRG and calprotectin were measured using commercial enzyme-linked immunosorbent assay kits. RESULTS: We enrolled 173 subjects, including 74 with CD, 77 with UC, and 22 NC. Serum LRG concentrations in active CD (median, 200 µg/mL) were significantly greater than in remission (81 µg/mL; P < 0.001) or NC (69 µg/mL; P < 0.001). Serum calprotectin concentrations in active CD (2941 ng/mL) also were significantly greater than in remission (962 ng/mL; P < 0.05) or NC (872 ng/mL; P < 0.05). Serum LRG concentrations in active UC (134 µg/mL) were significantly greater than in remission (65 µg/mL; P < 0.01) but not significantly greater than in NC (69 µg/mL); serum calprotectin concentrations in active UC (1058 ng/mL) were not significantly different from those in remission (671 ng/mL) or NC (872 ng/mL). In receiver operating characteristic analyses of LRG, calprotectin, C-reactive protein, and erythrocyte sedimentation rate for ability to distinguish active IBD from remission, CD and UC showed areas under receiver operating characteristic curves for LRG (0.77 and 0.70, respectively), exceeding those for calprotectin, C-reactive protein, or erythrocyte sedimentation rate. CONCLUSIONS: In pediatric IBD, serum LRG may better reflect disease activity than serum calprotectin, particularly in CD.