Histological grading evaluation of non-alcoholic fatty liver disease after bariatric surgery: a retrospective and longitudinal observational cohort study

Correlation analysis of dynamic changes of abdominal fat during rapid weight loss after bariatric surgery: A prospective magnetic resonance imaging study

OBJECTIVE

The factors related to the changes in the liver and abdominal adipose tissue during the rapid weight loss after bariatric surgery remain uncertain.

METHODS

This study included 44 participants who had undergone sleeve gastrectomy. The study aimed to analyze changes and correlations of body weight (BW), laboratory tests, and magnetic resonance imaging (MRI) indicators of the liver and abdominal adipose tissue conducted before and after bariatric surgery at 1, 3, and 6 months.

RESULTS

Following a rapid weight loss within 6 months of surgery, there was a concurrent decrease in blood glucose, blood lipids, and fat content of the liver and abdomen and the changes showed a correlation. The change of BW (ΔBW) was positively correlated with the change of hepatic proton density fat fraction (ΔPDFF) in one and three months after surgery and was positively correlated with the change of abdominal visceral fat area (ΔAVFA) in six months after surgery, (P<0.05). In one month after surgery, ΔPDFF was positively correlated with the change of aspartate aminotransferase (ΔAST), change of alanine aminotransferase (ΔALT), and change of triglyceride glucose (ΔTYG) index (P<0.05). ΔPDFF was positively correlated with the change of hepatic native T1 values (P<0.001) and was moderately negatively correlated with the change of hepatic apparent diffusion coefficient (ΔADC) values in three months after surgery (P<0.05).

CONCLUSION

ΔBW can serve as an indirect indicator for evaluating changes in liver fat fraction at 1 and 3 months after bariatric surgery and indicative of changes in visceral fat 6 months after surgery. ΔPDFF was positively correlated with ΔAST, ΔALT and ΔTYG index in 1 months after surgery.

Bariatric intervention improves metabolic dysfunction-associated steatohepatitis in patients with obesity: A systematic review and meta-analysis

BACKGROUND/AIMS

Bariatric intervention has been reported to be an effective way to improve metabolic dysfunction-associated steatotic liver disease (MASLD) in obese individuals. The current systemic review aimed to assess the changes in MRI-determined hepatic proton density fat fraction (MRI-PDFF) and nonalcoholic fatty liver disease activity score (NAS) after bariatric surgery or intragastric balloon/gastric banding in MASLD patients with obesity.

METHODS

We searched various databases including PubMed, OVID Medline, EMBASE, and Cochrane Library. Primary outcomes were the changes in intrahepatic fat on MRI-PDFF and histologic features of metabolic dysfunction-associated steatohepatitis (MASH).

RESULTS

Thirty studies with a total of 3,134 patients were selected for meta-analysis. Bariatric intervention significantly reduced BMI (ratio of means, 0.79) and showed 72% reduction of intrahepatic fat on MRI-PDFF at 6 months after bariatric intervention (ratio of means, 0.28). Eight studies revealed that NAS was reduced by 60% at 3-6 months compared to baseline, 40% at 12-24 months, and 50% at 36-60 months. Nineteen studies revealed that the proportion of patients with steatosis decreased by 44% at 3-6 months, 37% at 12-24 months, and 29% at 36-60 months; lobular inflammation by 36% at 12-24 months and 51% at 36-60 months; ballooning degeneration by 38% at 12-24 months; significant fibrosis (≥F2) by 18% at 12-24 months and by 17% at 36-60 months after intervention.

CONCLUSION

Bariatric intervention significantly improved MRI-PDFF and histologic features of MASH in patients with obesity. Bariatric intervention might be the effective alternative treatment option for patients with MASLD who do not respond to lifestyle modification or medical treatment.

Recompensation in MASLD-related cirrhosis via metabolic bariatric surgery

The prognosis of patients with decompensated cirrhosis is poor, with significantly increased liver-related mortality rates. With the rising tide of decompensated cirrhosis associated with metabolic dysfunction-associated steatotic liver disease (MASLD), the role of metabolic bariatric surgery (MBS) in achieving hepatic recompensation is garnering increasing attention. However, the complexity of preoperative assessment, the risk of postoperative disease recurrence, and the potential for patients to experience surgical complications of the MBS present challenges. In this opinion article we analyze the potential of MBS to induce recompensation in MASLD-related cirrhosis, discuss the mechanisms by which MBS may affect recompensation, and compare the characteristics of different MBS procedures; we highlight the therapeutic potential of MBS in MASLD-related cirrhosis recompensation and advocate for research in this complex area.

Berberine Effects in Pre-Fibrotic Stages of Non-Alcoholic Fatty Liver Disease-Clinical and Pre-Clinical Overview and Systematic Review of the Literature

Non-alcoholic fatty liver disease (NAFLD) is the predominant cause of chronic liver conditions, and its progression is marked by evolution to non-alcoholic steatosis, steatohepatitis, cirrhosis related to non-alcoholic steatohepatitis, and the potential occurrence of hepatocellular carcinoma. In our systematic review, we searched two databases, Medline (via Pubmed Central) and Scopus, from inception to 5 February 2024, and included 73 types of research (nine clinical studies and 64 pre-clinical studies) from 2854 published papers. Our extensive research highlights the impact of Berberine on NAFLD pathophysiology mechanisms, such as Adenosine Monophosphate-Activated Protein Kinase (AMPK), gut dysbiosis, peroxisome proliferator-activated receptor (PPAR), Sirtuins, and inflammasome. Studies involving human subjects showed a measurable reduction of liver fat in addition to improved profiles of serum lipids and hepatic enzymes. While current drugs for NAFLD treatment are either scarce or still in development or launch phases, Berberine presents a promising profile. However, improvements in its formulation are necessary to enhance the bioavailability of this natural substance.

Liver fat content assessed by conventional B-mode ultrasound and metabolic profile in non-diabetic patients: Implications for clinical practice

Introduction

Several studies have demonstrated a positive correlation between severe hepatic steatosis and metabolic alterations; however, few studies have addressed the potential association between different grades of steatosis and clinical patterns in a non-diabetic population.

Methods

We conducted a cross-sectional study of 223 non-diabetic individuals. The severity of steatosis was assessed using B-mode ultrasound. We analyzed lipid and glucose profiles according to the severity of hepatic steatosis. Estimated glomerular filtration rate (eGFR) values were also recorded to investigate the potential impact of steatosis on kidney function.

Results

Patients with steatosis were found to have higher insulinemia and mean values of fasting plasma glucose compared to patients without steatosis. A significant decrease in high-density lipoprotein level was observed only in patients with severe or moderate steatosis. All grades of steatosis were associated with increased triglyceride levels, which were more significant in severe steatosis. Subgroup analysis by body mass index demonstrated a significant difference between lean patients with steatosis and lean patients without steatosis for triglycerides (p = 0.002) and high-density lipoprotein levels (p = 0.019). Finally, patients diagnosed with steatosis demonstrated a higher prevalence of estimated glomerular filtration rate < 90 ml/min.

Conclusion

The degree of steatosis diagnosed at ultrasound may predict glucose or lipid metabolism disorders and a decline in kidney function in a non-diabetic population.

Bariatric Surgery and Metabolic Dysfunction-Associated Fatty Liver Disease: a 2022 Update

Non-alcoholic fatty liver disease (NAFLD) has been recently termed metabolic dysfunction-associated fatty liver disease (MAFLD) to address the strong association with the metabolic syndrome. The prevalence of MAFLD is significantly increased in obese individuals and treatment of obesity is currently the cornerstone of management of MAFLD. Bariatric and metabolic surgery nowadays emerges as a key therapeutic strategy for the treatment of the MAFLD. This review aims to provide an update on the novel studies reporting the outcomes of bariatric surgery on the spectrum of MAFLD, from hepatic steatosis to cirrhosis.

Reliability of Non-invasive Liver Fibrosis Assessment Tools Versus Biopsy in Pre- and Post-bariatric Surgery Patients with Non-alcoholic Fatty Liver Disease

PURPOSE

Liver biopsy (LBx) remains the gold standard to assess fibrosis in non-alcoholic fatty liver disease (NAFLD). Biochemical markers are also useful, but their reliability is not clear in patients with morbid obesity. We assessed the performance of six non-invasive fibrosis assessment tools before and after bariatric surgery (BSx) using LBx.

MATERIALS AND METHODS

This is a cross-sectional and prospective cohort study. LBx was performed at the time of BSx and 12-month post-operatively and assessed using the Brunt system. Clinical and biochemical measurements were collected at the same time points and six non-invasive fibrosis assessment tools were calculated.

RESULTS

One hundred seventy patients had BSx; 79.4% female; age was 46.6 ± 9.8 years, and BMI was 48.6 ± 7.5 kg/m². From liver histology, 88% had F0-F2 and 11.2% F3-F4. At BSx, aspartate aminotransferase to platelet ratio index (APRI) and FIB-4 had better accuracy (0.86 and 0.88) with specificity of 96.6% and 94.0% and negative predictive values (NPV) of 88.9% and 93.7%. However, sensitivity (6.7% and 40.0%) and positive predictive values (PPV) (20.0% and 46.2%) were low. Twelve months post-surgery (n = 54), 88.9% of patients had F0-F2 and 11.1% had F3-F4. Fibrosis-4 index (FIB-4) and NAFLD fibrosis score (NFS) had the best accuracy (0.79 and 0.77) with specificity of 83.7% and 86.9% and NPV of 92.3% and 86.9%. However, sensitivity (25% and 0%) and PPV (12.5% and 0%) were low.

CONCLUSION

Overall, FIB-4, APRI, and NFS showed similar performances with higher accuracy, specificity, and NPV. Sensitivity and PPV were low. These tests are more useful at excluding advanced fibrosis.

Comparative effectiveness of medical treatment vs. metabolic surgery for histologically proven non-alcoholic steatohepatitis and fibrosis: a matched network meta-analysis

Background

Non-alcoholic steatohepatitis (NASH) comprises a major healthcare problem affecting up to 30% of patients with obesity and the associated risk for cardiovascular and liver-related mortality. Several new drugs for NASH-treatment are currently investigated. No study thus far directly compared surgical and non-surgical therapies for NASH. This network meta-analysis compares for the first time the effectiveness of different therapies for NASH using a novel statistical approach.

Methods

The study was conducted according to the PRISMA guidelines for network meta-analysis. PubMed, CENTRAL and Web of Science were searched without restriction of time or language using a validated search strategy. Studies investigating therapies for NASH in adults with liver biopsies at baseline and after at least 12 months were selected. Patients with liver cirrhosis were excluded. Risk of bias was assessed with ROB-2 and ROBINS-I-tools. A novel method for population-adjusted indirect comparison to include and compare single-arm trials was applied. Main outcomes were NASH-resolution and improvement of fibrosis.

Results

Out of 7,913 studies, twelve randomized non-surgical studies and twelve non-randomized surgical trials were included. NASH-resolution after non-surgical intervention was 29% [95% confidence interval (CI): 23-40%] and 79% (95% CI: 72-88%) after surgery. The network meta-analysis showed that surgery had a higher chance of NASH-resolution than medication [odds ratio (OR) =2.68; 95% CI: 1.44-4.97] while drug treatment was superior to placebo (OR =2.24; 95% CI: 1.55-3.24). Surgery (OR =2.18; 95% CI: 1.34-3.56) and medication (OR =1.79; 95% CI: 1.39-2.31) were equally effective to treat fibrosis compared to placebo without difference between them. The results did not change when only new drugs specifically developed for the treatment of NASH were included.

Conclusions

Metabolic surgery has a higher effectiveness for NASH-therapy than medical therapy while both were equally effective regarding improvement of fibrosis. Trials directly comparing surgery with medication must be urgently conducted. Patients with NASH should be informed about surgical treatment options.

Comparison of reader agreement, correlation with liver biopsy, and time-burden sampling strategies for liver proton density fat fraction measured using magnetic resonance imaging in patients with obesity: a secondary cross-sectional study

Background

The magnetic resonance imaging (MRI)-based proton density fat fraction (PDFF) has become popular for quantifying liver fat content. However, the variability of the region-of-interest (ROI) sampling strategy may result in a lack of standardisation of this technology. In an effort to establish an accurate and effective PDFF measurement scheme, this study assessed the pathological correlation, the reader agreement, and time-burden of different sampling strategies with variable ROI size, location, and number.

Methods

Six-echo spoiled gradient-recalled-echo magnitude-based fat quantification was performed for 50 patients with obesity, using a 3.0-T MRI scanner. Two readers used different ROI sampling strategies to measure liver PDFF, three times. Intra-reader and inter-reader agreement was evaluated using intra-class correlation coefficients and Bland‒Altman analysis. Pearson correlations were used to assess the correlation between PDFFs and liver biopsy. Time-burden was recorded.

Results

For pathological correlations, the correlations for the strategy of using three large ROIs in Couinaud segment 3 (S3 3L-ROI) were significantly greater than those for all sampling strategies at the whole-liver level (P < 0.05). For inter-reader agreement, the sampling strategies at the segmental level for S3 3L-ROI and using three large ROIs in Couinaud segment 6 (S6 3L-ROI) and the sampling strategies at the whole-liver level for three small ROIs per Couinaud segment (27S-ROI), one large ROI per Couinaud segment (9L-ROI), and three large ROIs per Couinaud segment (27S-ROI) had limits of agreement (LOA) < 1.5%. For intra-reader agreement, the sampling strategies at the whole-liver level for 27S-ROI, 9L-ROI, and 27L-ROI had both intraclass coefficients > 0.995 and LOAs < 1.5%. The change in the time-burden was the largest (100.80 s) when 9L-ROI was changed to 27L-ROI.

Conclusions

For hepatic PDFF measurement without liver puncture biopsy as the gold standard, and for general hepatic PDFF assessment, 9L-ROI sampling strategy at the whole-liver level should be used preferentially. For hepatic PDFF with liver puncture biopsy as the gold standard, 3L-ROI sampling strategy at the puncture site segment is recommended.

Bariatric Surgery Improves Nonalcoholic Fatty Liver Disease: Systematic Review and Meta-Analysis

PURPOSE

Bariatric surgery has been uncovered to relieve nonalcoholic fatty liver disease (NAFLD) in patients with obesity, while current studies have neutral or opposite results. This systematic review and meta-analysis aimed to evaluate the effects of bariatric surgery on NAFLD in patients with obesity.

MATERIALS AND METHODS

PubMed, Embase, Cochrane Central, and Web of Science databases were performed to obtain publications containing comparison results of liver biopsy before and after bariatric surgery in obesity. Primary outcomes were biopsy-confirmed remission of NAFLD and NAFLD activity scores. Secondary outcomes were liver function. This study was registered with PROSPERO, CRD42021240346.

RESULTS

Thirty-seven studies were included. After bariatric surgery, a biopsy-confirmed resolution of steatosis was improved in 56% of patients, ballooning degeneration in 49%, inflammation in 45%, and fibrosis in 25%. Bariatric surgery significantly decreased mean NAFLD activity scores. RYGB achieved the most obviously improvements in steatosis, and SG attained the most notably ameliorations in fibrosis. The percentage of patients with improved steatosis and hepatic fibrosis in Asian countries was higher than non-Asian countries. The reduction of ALT and AST was 11.95U/L and 6.44 U/L after surgery.

CONCLUSION

Our study has revealed that bariatric surgery brought out significantly resolution of NAFLD in individuals with obesity. RYGB and SG have been proved to be of benefit to many hepatic parameters, and the improvement of liver steatosis and fibrosis, particularly in Asian countries. It is strongly suggested that bariatric surgery should be considered as a novel treatment for NAFLD.

Improvement of Type 2 Diabetes Mellitus and Attenuation of NAFLD Are Associated with the Success of Obesity Therapy

Obesity and type 2 diabetes mellitus (T2D) represent important comorbidities of the metabolic syndrome, which are associated with non-alcoholic fatty liver disease (NAFLD)-related hepatic fibrosis. In total, 160 morbidly obese patients-81 following a low-calorie formula diet (LCD) program and 79 undergoing bariatric surgery (Roux-en-Y gastric bypass, RYGB)-were examined for anthropometric and metabolic parameters at base-line and during 12 months of weight loss, focusing on a putative co-regulation of T2D parameters and liver fibrosis risk. High NAFLD fibrosis scores (NFS) before intervention were associated with elevated HbA1c levels and T2D. Loss of weight and body fat percentage (BFL) were associated with improved glucose and lipid metabolism and reduced risk of NAFLD-related fibrosis, with particularly beneficial effects by RYGB. Both T2D improvement and NFS decrease were positively associated with high BFL. A highly significant correlation of NFS reduction with BFL was restricted to male patients while being absent in females, accompanied by generally higher BFL in men. Overall, the data display the relation of BFL, T2D improvement, and reduced NAFLD-related fibrosis risk during weight loss in morbidly obese individuals induced by diet or RYGB. Furthermore, our data suggest a considerable sexual dimorphism concerning the correlation of fat loss and improved risk of liver fibrosis.

The relationship between Lipocalin-2 level and hepatic steatosis in obese patients with NAFLD after bariatric surgery

BACKGROUND

Lipocalin-2 (LCN2) has a critical effect on obesity as well as its associated comorbidities. The present study focused on analyzing serum LCN2 levels of obese patients with nonalcoholic fatty liver disease (NAFLD) and on determining relationship of hepatic steatosis improvement with LCN2 levels after laparoscopic sleeve gastrectomy (LSG).

METHODS

This work enrolled ninety patients with obesity and NAFLD. Twenty-three of them underwent LSG. Anthropometric and biochemical parameters and serum LCN2 levels were determined at baseline and those at 6-month post-LSG. Controlled attenuation parameter (CAP) measured by FibroScan was adopted for evaluating hepatic steatosis.

RESULTS

Among severe obesity patients, serum LCN2 levels were significantly increased (111.59 ± 51.16 ng/mL vs. 92.68 ± 32.68 ng/mL, P = 0.035). The CAP value was higher indicating higher liver fat content (360.51 ± 45.14 dB/m vs. 340.78 ± 45.02 dB/m, P = 0.044). With regard to surgical patients, liver function, glucose, and lipid levels were significantly improved after surgery. Serum LCN2 levels significantly decreased (119.74 ± 36.15 ng/mL vs. 87.38 ± 51.65 ng/mL, P = 0.001). Decreased CAP indicated a significant decrease in liver fat content (358.48 ± 46.13 dB/m vs. 260.83 ± 69.64 dB/m, P < 0.001). The decrease in LCN2 levels was significantly related to the reduced hepatic fat content and improvement in steatosis grade after adjusting for gender, age, and BMI decrease.

CONCLUSIONS

Serum LCN2 levels are related to obesity and NAFLD. The decreased serum LCN2 levels could be an indicator of hepatic steatosis improvement.

Genetic Polymorphisms and Clinical Features in Diabetic Patients With Fatty Liver: Results From a Single-Center Experience in Southern Italy

Genetic background may be involved in the promotion and progression of non-alcoholic fatty liver disease (NAFLD). Previous studies have suggested that the single nucleotide polymorphisms (SNPs) may be associated with the specific clinical features in the patients with hepatic steatosis; however, data on the patients with diabetes from Southern Italy are lacking. We enrolled 454 patients and 260 of them had type 2 diabetes. We studied the PNPLA3 rs738409, LPIN1 rs13412852, KLF6 rs3750861, SOD2 rs4880, TM6SF2 rs58542926, and ZNF624 rs12603226 SNPs and their distribution in the study population. Lipid profile, liver stiffness, and kidney function were also studied to understand the potential role of the SNPs in the development of clinical phenotypes. No differences were observed in the distribution of polymorphisms between the diabetic and non-diabetic subjects. Carriers of risk allele G for PNPLA3 rs738409 SNP showed a lower mean value of serum triglycerides and a higher liver stiffness. Risk allele for KLF6 rs3750861 and SOD2 rs4880 polymorphism had a lower estimated glomerular filtration rate (eGFR) value, whereas no differences in the glucose and glycated hemoglobin level were observed in the subgroups by the different genotypes. Genetic polymorphisms are useful to identify the patients at higher risk of development of liver fibrosis and lower eGFR values in the patients with diabetes and NAFLD. Their use in clinical practice may help the clinicians to identify the patients who require a more strict follow-up program.

Differences between current clinical guidelines for screening, diagnosis and management of nonalcoholic fatty liver disease and real-world practice: a targeted literature review

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease and is associated with obesity and metabolic comorbidities. Liver steatosis can progress to nonalcoholic steatohepatitis (NASH) exhibiting a relevant risk of fibrosis and ultimately liver failure. To date, no approved treatment for NASH to reduce its clinical and humanistic burden has been developed.

AREAS COVERED

We undertook a literature review to identify English language, national and international clinical guidelines for NAFLD regarding diagnosis, assessment and management, and determined their points of agreement and difference. Additionally, we investigated published literature relating to real-world management of NAFLD and NASH.

EXPERT OPINION

National (China, England/Wales, Italy, the USA) and international society (Asia-Pacific, Europe, World Gastroenterology Organization) guidelines were identified and analyzed. All guidelines addressed identifying and diagnosing subjects with likely NAFLD, as well as assessment and management of individuals with risk factors for advanced disease, including fibrosis. Real-world practice reveals widespread suboptimal awareness and implementation of guidelines. In the absence of proven therapeutics, such gaps risk failure to recognize patients in need of specialist care and monitoring, highlighting the need for clear, easy-to-apply care pathways to aid in reducing the clinical and humanistic burden of NAFLD and NASH.

Bariatric surgery for non-alcoholic fatty liver disease in individuals with obesity (Base-NAFLD): protocol of a prospective multicenter observational follow-up study

BACKGROUND

Bariatric surgery may be indicated in patients with nonalcoholic fatty liver disease (NAFLD) to achieve and maintain the degree of weight loss required to ensure therapeutic effects. However, bariatric surgery is still underrecognized in the treatment of NAFLD, including its inflammatory subtype, nonalcoholic steatohepatitis (NASH). Moreover, there is a lack of follow-up outcome data on different types of bariatric surgery in patients with NAFLD. This study aims to adequately assess the effect of bariatric surgery on NAFLD remission in obese patients.

METHODS

This prospective multicentre observational follow-up study will include 142 obese patients with NAFLD scheduled to undergo one of the following surgical procedures: sleeve gastrostomy, Roux-en-Y gastric bypass, and one anastomosis gastric bypass. The primary outcome is the complete remission rate of NAFLD one year postoperatively, which is defined by liver fat fraction < 5% on magnetic resonance imaging; the secondary outcomes includes (i) changes in NASH and liver fibrosis biopsy findings, (ii) changes in body weight and abdominal adipose weight, (iii) resolution of obesity-related comorbidities, and (iv) incidence of adverse events. A long-term follow-up related to this study will also be conducted.

DISCUSSION

This study will provide a necessary and preliminary foundation for the early identification and targeted treatment of patients with NAFLD who can be referred for bariatric surgery, as indicated for management of obesity and metabolic disease.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04366999. Registered 21 April 2020. ( https://clinicaltrials.gov/ct2/show/NCT04366999 ).

Diabetic fibrosis

Diabetes-associated morbidity and mortality is predominantly due to complications of the disease that may cause debilitating conditions, such as heart and renal failure, hepatic insufficiency, retinopathy or peripheral neuropathy. Fibrosis, the excessive and inappropriate deposition of extracellular matrix in various tissues, is commonly found in patients with advanced type 1 or type 2 diabetes, and may contribute to organ dysfunction. Hyperglycemia, lipotoxic injury and insulin resistance activate a fibrotic response, not only through direct stimulation of matrix synthesis by fibroblasts, but also by promoting a fibrogenic phenotype in immune and vascular cells, and possibly also by triggering epithelial and endothelial cell conversion to a fibroblast-like phenotype. High glucose stimulates several fibrogenic pathways, triggering reactive oxygen species generation, stimulating neurohumoral responses, activating growth factor cascades (such as TGF-β/Smad3 and PDGFs), inducing pro-inflammatory cytokines and chemokines, generating advanced glycation end-products (AGEs) and stimulating the AGE-RAGE axis, and upregulating fibrogenic matricellular proteins. Although diabetes-activated fibrogenic signaling has common characteristics in various tissues, some organs, such as the heart, kidney and liver develop more pronounced and clinically significant fibrosis. This review manuscript summarizes current knowledge on the cellular and molecular pathways involved in diabetic fibrosis, discussing the fundamental links between metabolic perturbations and fibrogenic activation, the basis for organ-specific differences, and the promises and challenges of anti-fibrotic therapies for diabetic patients.

Liver biopsy in the quantitative assessment of liver fibrosis in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) is a major cause of liver fibrosis/cirrhosis and liver-related mortality. Despite emergence of noninvasive tests, liver biopsy remains the mainstay for the diagnosis and assessment of disease severity and chronicity. Accurate detection and quantification of liver fibrosis with architectural localization are essential for assessing the severity of NAFLD and its response to antifibrotic therapy in clinical trials. Conventional histological scoring systems for liver fibrosis are semiquantitative. Collagen proportionate area is morphometric by measuring the percentage of fibrosis on a continuous scale but is limited by the absence of architectural input. Ultra-fast laser microscopy, e.g., second harmonic generation (SHG) imaging, has enabled in-depth analysis of fibrillary collagen based on intrinsic optical signals. Quantification and calculation of different detailed variables of collagen fibers can be used to establish algorithm-based quantitative fibrosis scores (e.g. qFibrosis, q-FPs) in NAFLD. Artificial intelligence is being explored to further develop quantitative fibrosis scoring methods. SHG microscopy should be considered the new gold standard for the quantitative assessment of liver fibrosis, reaffirming the pivotal role of the liver biopsy in NAFLD, at least for the near-future. The ability of SHG-derived algorithms to intuitively detect subtle nuances in liver fibrosis changes over a continuous scale should be employed to redress the efficacy endpoint for fibrosis in NASH clinical trials. The current decrease by 1-point or more in fibrosis stage may not be realistic for the evaluation of therapeutic response to antifibrotic drugs in relatively short-term trials.

Modifications of IGF2 and EGFR plasma protein concentrations in NAFLD patients after bariatric surgery

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is strictly associated with the epidemic of obesity and is becoming the most prevalent liver disease worldwide. In severe obesity, bariatric surgery (BS) is the most effective treatment not only for obesity but also for the associated metabolic co-morbidities, NAFLD, among others. To date, noninvasive diagnostic/prognostic methods cannot evaluate hepatic improvements following surgery.

OBJECTIVES

We aimed to measure plasma level of insulin-growth factor-2 protein (IGF2) and epithermal growth factor receptor (EGFR), and to assess their relationship with clinical and biochemical parameters during the 12 months follow-up.

METHODS

Demographic, clinical-biochemical data, and plasma IGF2 and EGFR were measured in 69 patients preoperatively (T0) and 6 and 12 months (T6M and T12M, respectively) after BS. Liver biopsy was performed at T0. Relationships between IGF2, EGFR, and several biochemical parameters were performed using Pearson or Spearman correlation analysis.

RESULTS

IGF2 plasma level increases during follow-up, passing from 2.5 (1.8-15.5) at baseline to 13.3 (8.6-19.1) at T12M, p < 0.001. Conversely, EGFR showed a not significant reduction. At T12M, the plasma level of both markers was comparable to those of lean subjects. The clinical-biochemical parameters (BMI, glycated hemoglobin, HOMA-IR) also return to the normal range at T12M. Correlation analysis demonstrated that IGF2 was significantly associated with total bilirubin, direct bilirubin, and albumin at T0 while with blood glucose, ALT, GGT, and AST/ALT ratio at T6M and T12M.

CONCLUSIONS

IGF2 plasma levels increase after bariatric surgery, and these changes are associated with the modification of hepatic biochemical parameters, even if other clinic or metabolic improvements cannot be excluded.