Hepatic steatosis depresses alpha-1-antitrypsin levels in human and rat acute pancreatitis

Fatty Liver, Statin Therapy, and the Risk of Hypertriglyceridemic Acute Pancreatitis: A Retrospective Study

OBJECTIVES

Identifying patients with severe hypertriglyceridemia (HTG) who are prone to developing hypertriglyceridemic pancreatitis (HTGP) is essential for facilitating preventative interventions. This research aims to explore which part of the HTG patients is easy to develop into HTGP.

MATERIALS AND METHODS

An observational cohort study was conducted in patients with serum triglycerides (TGs) ≥ 5.65 mmol/L. Propensity score matching (PSM) and logistic regression were used to adjust for potential confounding factors. Receiver operating characteristic (ROC) curves were applied to evaluate the predictive potential for HTGP.

RESULTS

A total of 283 patients were included finally with a PSM cohort consisting of 55 HTGP matched with 77 non-HTGP. In multivariate logistic regression analysis, fatty liver (FL) (odds ratio, 2.535; P = 0.019) showed statistically significant association with HTGP, whereas statin use was correlated with a lower rate of HTGP (odds ratio, 0.203; P = 0.009). Finally, the ROC analysis showed that the TGs threshold thought to be causal of HTGP in patients with FL was significantly lower (9.31 vs 14.67 mmol/L) than that in patients without FL.

CONCLUSIONS

Although with lower TGs levels, patients with FL are much more prone to generate HTGP, and our findings suggest a potential role of statin as protective agents against HTGP.

Nonalcoholic fatty liver disease aggravates acute pancreatitis through bacterial translocation and cholesterol metabolic dysregulation in the liver and pancreas in mice

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for severe acute pancreatitis (AP). The underlying mechanism remains unclear. We sought to determine how bacterial translocation and cholesterol metabolism in the liver and pancreas affect the severity of AP in NAFLD mice.

METHODS

C57BL/6N mice were fed on a high-fat diet (HFD) to generate the NAFLD model, and mice in the control group were provided with a normal diet (ND). After being anesthetized with ketamine/xylazine, mice got a retrograde infusion of taurocholic acid sodium into the pancreatic duct to induce AP, and sham operation (SO) was used as control. Serum amylase and Schmidt's pathological score system were used to evaluate AP severity. Bacterial loads, total cholesterol level, and cholesterol metabolic-associated molecules [low-density lipoprotein receptor (LDLR) and ATP-binding cassette transporter A1 (ABCA1)] were analyzed in the liver and pancreas.

RESULTS

Compared with the ND-AP group, mice in the HFD-AP group had severer pancreatitis, manifested with higher serum amylase levels and higher AP pathologic scores, especially the inflammation and hemorrhage scores. Compared with the HFD-SO group and ND-AP group, bacterial loads in the liver and pancreas were significantly higher in the HFD-AP group. Mice in the HFD-AP group showed a decreased LDLR expression and an increased ABCA1 expression in the pancreas, although there was no significant difference in pancreas total cholesterol between the HFD-AP group and the ND-AP group.

CONCLUSIONS

NAFLD aggravates AP via increasing bacterial translocation in the liver and pancreas and affecting pancreas cholesterol metabolism in mice.

Metabolic-associated fatty liver disease is associated with acute pancreatitis with more severe course: Post hoc analysis of a prospectively collected international registry

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is a proven risk factor for acute pancreatitis (AP). However, NAFLD has recently been redefined as metabolic-associated fatty liver disease (MAFLD). In this post hoc analysis, we quantified the effect of MAFLD on the outcomes of AP.

METHODS

We identified our patients from the multicentric, prospective International Acute Pancreatitis Registry of the Hungarian Pancreatic Study Group. Next, we compared AP patients with and without MAFLD and the individual components of MAFLD regarding in-hospital mortality and AP severity based on the revised Atlanta classification. Lastly, we calculated odds ratios (ORs) with 95% confidence intervals (CIs) using multivariate logistic regression analysis.

RESULTS

MAFLD had a high prevalence in AP, 39% (801/2053). MAFLD increased the odds of moderate-to-severe AP (OR = 1.43, CI: 1.09-1.89). However, the odds of in-hospital mortality (OR = 0.89, CI: 0.42-1.89) and severe AP (OR = 1.70, CI: 0.97-3.01) were not higher in the MAFLD group. Out of the three diagnostic criteria of MAFLD, the highest odds of severe AP was in the group based on metabolic risk abnormalities (OR = 2.68, CI: 1.39-5.09). In addition, the presence of one, two, and three diagnostic criteria dose-dependently increased the odds of moderate-to-severe AP (OR = 1.23, CI: 0.88-1.70, OR = 1.38, CI: 0.93-2.04, and OR = 3.04, CI: 1.63-5.70, respectively) and severe AP (OR = 1.13, CI: 0.54-2.27, OR = 2.08, CI: 0.97-4.35, and OR = 4.76, CI: 1.50-15.4, respectively). Furthermore, in patients with alcohol abuse and aged ≥60 years, the effect of MAFLD became insignificant.

CONCLUSIONS

MAFLD is associated with AP severity, which varies based on the components of its diagnostic criteria. Furthermore, MAFLD shows a dose-dependent effect on the outcomes of AP.

Mechanisms linking hypertriglyceridemia to acute pancreatitis

Hypertriglyceridemia (HTG) is a metabolic disorder, defined when serum or plasma triglyceride concentration (seTG) is >1.7 mM. HTG can be categorized as mild to very severe groups based on the seTG value. The risk of acute pancreatitis (AP), a serious disease with high mortality and without specific therapy, increases with the degree of HTG. Furthermore, even mild or moderate HTG aggravates AP initiated by other important etiological factors, including alcohol or bile stone. This review briefly summarizes the pathophysiology of HTG, the epidemiology of HTG-induced AP and the clinically observed effects of HTG on the outcomes of AP. Our main focus is to discuss the pathophysiological mechanisms linking HTG to AP. HTG is accompanied by an increased serum fatty acid (FA) concentration, and experimental results have demonstrated that these FAs have the most prominent role in causing the consequences of HTG during AP. FAs inhibit mitochondrial complexes in pancreatic acinar cells, induce pathological elevation of intracellular Ca²⁺ concentration, cytokine release and tissue injury, and reduce the function of pancreatic ducts. Furthermore, high FA concentrations can induce respiratory, kidney, and cardiovascular failure in AP. All these effects may contribute to the observed increased AP severity and frequent organ failure in patients. Importantly, experimental results suggest that the reduction of FA production by lipase inhibitors can open up new therapeutic options of AP. Overall, investigating the pathophysiology of HTG-induced AP or AP in the presence of HTG and determining possible treatments are needed.

The investigation of the frequency of the alpha-1-antitrypsin phenotype in patients with liver cirrhosis

OBJECTIVES

Alpha-1-antitrypsin (AAT) has different phenotypes. Evidence suggests that the abundance of each of these phenotypes may be associated with a disease. The purpose of this study was to evaluate the frequency of AAT phenotypes in patients with liver cirrhosis as well as in healthy individuals.

METHODS

In this study, 42 patients with liver cirrhosis were selected. The results of the previous research done by the researcher on healthy individuals were used to construct the control group. After obtaining informed consent, 5 mL of fasting venous blood sample was taken, and phenotypes were analyzed by isoelectric focusing. Data were analyzed using Chi-square and Fisher's exact tests at a significant level of 0.05.

RESULTS

The results of this study indicated that all 42 healthy subjects had an MM allele (100%). However, among 42 patients, 35 (83.3%) had an MM allele, 5 (11.9%) had an MS allele, and 2 (4.8%) had MZ allele. The difference between the two groups was significant (p=0.02). There was no difference between men and women in the allele type (p=0.557).

CONCLUSIONS

This study revealed that MS and MZ alleles were observed only in patients with liver cirrhosis, and none of these alleles were found in healthy subjects. Therefore, MS and MZ alleles can be further investigated as risk factors for liver cirrhosis.

Therapeutic Potential of Alpha-1 Antitrypsin in Type 1 and Type 2 Diabetes Mellitus

Alpha-1 antitrypsin (AAT) has established anti-inflammatory and immunomodulatory effects in chronic obstructive pulmonary disease but there is increasing evidence of its role in other inflammatory and immune-mediated conditions, like diabetes mellitus (DM). AAT activity is altered in both developing and established type 1 diabetes mellitus (T1DM) as well in established type 2 DM (T2DM). Augmentation therapy with AAT appears to favorably impact T1DM development in mice models and to affect β-cell function and inflammation in humans with T1DM. The role of AAT in T2DM is less clear, but AAT activity appears to be reduced in T2DM. This article reviews these associations and emerging therapeutic strategies using AAT to treat DM.

The undiagnosed disease burden associated with alpha-1 antitrypsin deficiency genotypes

Alpha-1 antitrypsin deficiency (AATD), mainly due to the PI*ZZ genotype in SERPINA1, is one of the most common inherited diseases. Since it is associated with a high disease burden and partially prevented by smoking cessation, identification of PI*ZZ individuals through genotyping could improve health outcomes.

We examined the frequency of the PI*ZZ genotype in individuals with and without diagnosed AATD from UK Biobank, and assessed the associations of the genotypes with clinical outcomes and mortality. A phenome-wide association study (PheWAS) was conducted to reveal disease associations with genotypes. A polygenic risk score (PRS) for forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio was used to evaluate variable penetrance of PI*ZZ.

Among 458 164 European-ancestry participants in UK Biobank, 140 had the PI*ZZ genotype and only nine (6.4%, 95% CI 3.4–11.7%) of them were diagnosed with AATD. Those with PI*ZZ had a substantially higher odds of COPD (OR 8.8, 95% CI 5.8–13.3), asthma (OR 2.0, 95% CI 1.4–3.0), bronchiectasis (OR 7.3, 95%CI 3.2–16.8), pneumonia (OR 2.7, 95% CI 1.5–4.9) and cirrhosis (OR 7.8, 95% CI 2.5–24.6) diagnoses and a higher hazard of mortality (2.4, 95% CI 1.2–4.6), compared to PI*MM (wildtype) (n=398 424). These associations were stronger among smokers. PheWAS demonstrated associations with increased odds of empyema, pneumothorax, cachexia, polycythaemia, aneurysm and pancreatitis. Polygenic risk score and PI*ZZ were independently associated with FEV₁/FVC <0.7 (OR 1.4 per 1-sd change, 95% CI 1.4–1.5 and OR 4.5, 95% CI 3.0–6.9, respectively).

The important underdiagnosis of AATD, whose outcomes are partially preventable through smoking cession, could be improved through genotype-guided diagnosis.

Only 6.4% of those with genotype-defined alpha-1 antitrypsin deficiency had been diagnosed with this serious disease in UK Biobank. Genotype-guided diagnosis could help to identify the thousands of people in the UK with this partially preventable disease. https://bit.ly/3dMu5Ng

Fatty Liver Disease and Non-Alcoholic Fatty Liver Disease Worsen the Outcome in Acute Pancreatitis: A Systematic Review and Meta-Analysis

The prevalence of fatty liver disease (FLD) and that of non-alcoholic fatty liver disease (NAFLD) share some risk factors known to exacerbate the course of acute pancreatitis (AP). This meta-analysis aimed to investigate whether FLD or NAFLD carry a higher risk of untoward outcomes in AP. In accordance with PRISMA guidelines, we performed a systematic search in seven medical databases for cohort studies that compared the outcomes of AP for the presence of FLD or NAFLD, and we calculated pooled odds ratio (OR) or weighted mean difference (WMD) with 95% confidence interval (CI). We included 13 articles in our meta-analysis. AP patients with FLD were more likely to die (5.09% vs 1.89%, OR = 3.56, CI = 1.75-7.22), develop severe AP (16.33% vs 7.87%, OR = 2.67, CI = 2.01-3.56), necrotizing pancreatitis (34.83% vs 15.75%, OR = 3.08, CI = 2.44-3.90) and had longer in-hospital stay (10.8 vs 9.2 days, WMD = 1.46, OR = 0.54-2.39). Patients with NAFLD were more likely to have severe AP and longer hospital stay. Both FLD and NAFLD proved to be independent risk factors of a more severe disease course (OR = 3.68, CI = 2.16-6.29 and OR = 3.39, CI = 1.52-7.56 for moderate/ severe vs. mild AP, respectively). FLD and NAFLD worsen the outcomes of AP, which suggests that incorporating FLD or NAFLD into prognostic scoring systems of AP outcomes might improve the prediction of severity and contribute to a more individualized patient care.

S100A9 as a novel diagnostic and prognostic biomarker in human gastric cancer

Objective: The morbidity and mortality of gastric cancer (GC) is high, but there are lack of the biomarkers for early diagnosis and progression of GC. We aimed to identify a novel biomarker for the growth and progression of GC.Methods: The Cancer Genome Atlas (TCGA) database including 352 eligible patients was used to screen candidate genes related to the prognosis of GC. A proteomics analysis of Chinese Human Proteome Sketches (CHPS) including 84 eligible sample tissues was conducted to further identify candidate biomarkers. A series of in vitro assays were performed to investigate the functions of candidate proteins in GC. Next, to verify whether the candidate oncogene was associated with gastric carcinogenesis, we screened its expression levels using samples from 200 patients with chronic atrophic gastritis (CAG), intestinal metaplasia (IM), dysplasia, or GC and healthy controls.Results: According to the analyses of the TCGA database and CHPS, we found that S100A9 may be associated with the prognosis of GC. The results of proliferation, wound-healing and invasion assays, immunohistochemistry (IHC) and western blot showed that high levels of S100A9 in tissues were significantly associated with GC aggressiveness and a poor prognosis (p < .05). Furthermore, we found that the expression of S100A9 increased gradually during the process of gastric carcinogenesis (p < .05). The diagnostic sensitivity and specificity of S100A9 as a biomarker for early GC were 61.4% and 81.3%, respectively.Conclusions: This study reveals that S100A9 may be a novel biomarker for the early diagnosis and prognosis of GC patients.

Relationships between Metabolic Comorbidities and Occurrence, Severity, and Outcomes in Patients with Acute Pancreatitis: A Narrative Review

Background. The population of patients with acute pancreatitis treated by the staff at our department of gastroenterology includes those with mild and self-limited disease ranging to those with severe and fatal disease. Early diagnosis and accurate prediction of the severity and outcome of this disease, which is commonly seen by our department, is important for a successful outcome. Metabolic comorbidities (e.g., diabetes mellitus, fatty liver, obesity, and metabolic syndrome) are relevant to the severity and progression of many diseases. The objective of this review was to examine clinical relationships between metabolic comorbidities and occurrence, severity, and outcome of acute pancreatitis.

Fatty liver disease is associated with the severity of acute pancreatitis:A systematic review and meta-analysis

BACKGROUND

Fatty liver (FL) has been positively associated with the risk of acute pancreatitis (AP), but whether FL is associated with the severity of AP remains unknown. To this, a meta-analysis was conducted to assess the effect of FL on severity and outcomes of AP.

METHOD

We searched PubMed, EMBASE and the Cochrane library to identify all eligible studies (up to June 2017). We pooled the odds ratios (ORs) or weighted mean differences (WMD) from individual studies using a random-effects model to investigate associations between FL and the prognosis of AP.

RESULT

Four studies were included in the meta-analysis, including a total of 805 patients with fatty liver-related acute pancreatitis (FLAP) and 1026 patients with non fatty liver-related acute pancreatitis (NFLAP). The incidences of moderately severe AP (MSAP) (OR = 2.72, 95%CI: 1.82-4.05, P < 0.001) and severe AP (SAP) (OR = 3.57, 95%CI: 2.06-6.18, P < 0.001) were statistically significantly higher in FLAP group than those in NFLAP group. Taking obesity into consideration, a higher rate of MSAP and SAP were also found in patients with FL, no matter whether they were obese or not. Furthermore, mortality (OR = 4.16, 95%CI: 2.57-6.73, P < 0.001), systemic inflammatory response syndrome (SIRS) (OR = 2.82, 95%CI: 2.3-3.47, P < 0.001) and local complications were also statistically significantly higher in the FLAP group than in NFLAP group.

CONCLUSION

Fatty liver is associated with the severity of acute pancreatitis.

Nonalcoholic Fatty Liver Disease Aggravated the Severity of Acute Pancreatitis in Patients

Background and Aim

The incidence of nonalcoholic fatty liver disease (NAFLD) as a metabolic disease is increasing annually. In the present study, we aimed to explore the influence of NAFLD on the severity of acute pancreatitis (AP).

Methods

The severity of AP was diagnosed and analyzed according to the 2012 revised Atlanta Classification. Outcome variables, including the severity of AP, organ failure (all types of organ failure), and systemic inflammatory response syndrome (SIRS), were compared for patients with and without NAFLD.

Results

Six hundred and fifty-six patients were enrolled in the study and were divided into two groups according to the presence or absence of NAFLD. The non-NAFLD group contained 278 patients and the main etiology in this group was gallstone. The NAFLD group consisted of 378 patients and the main etiology was hyperlipidemia. The incidence of mild AP, moderately severe AP, and severe AP was 77.30%, 18.3%, and 4.3% in the non-NAFLD group and 58.2%, 33.9%, and 7.9% in the NAFLD group, respectively. There were significant differences between the two groups according to the severity of AP (P ≤ 0.001). In addition, the Ranson and BISAP scores as well as the incidence of SIRS and organ failure in the NAFLD group were higher than those in the non-NAFLD group (all P < 0.05). The patients were further divided into non-NAFLD, mild-NAFLD, and moderate-severe NAFLD (M+S-NAFLD) groups. The results showed that the severity of AP increased gradually from the non-NAFLD group to the M+S-NAFLD group. In addition, the incidence rates of SIRS and organ failure showed an upward trend with the aggravation of fatty liver severity. Multivariate logistic analysis showed that patients with NAFLD, especially those with M+S-NAFLD, had higher risks of SIRS and organ failure.

Conclusions

Compared with non-NAFLD, NAFLD has a clinically relevant impact on the severity of AP and may be an early prognostic parameter for patients with AP.

Hepatic steatosis in participants in a program of low-dose CT screening for lung cancer

OBJECTIVE

Determine the frequency of moderate-to-severe hepatic steatosis (HS) in asymptomatic participants in a low-dose CT (LDCT) screening program for lung cancer, to identify risk factors, and develop recommendations.

METHODS

Baseline LDCT scans of the chest of 170 participants in an IRB-approved study between August 2011 and April 2016 were reviewed. Demographic variables, comorbidities, and liver function tests were documented. Hepatic and splenic attenuation values hounsfield unit (HU) were measured. Regression analyses were performed.

RESULTS

Average liver attenuation was 57.6HU (standard deviation (SD) 9.3) and average liver/spleen (L/S) ratio was 1.3 (SD 0.3). Liver attenuation was <40HU for 9 (5.3%), liver/spleen (L/S) ratio <0.8 for 6 (3.5%), and either <40HU or L/S ratio <0.8 for 9 (5.3%). Male sex (p=0.004), diabetes (p=0.0005), emphysema (p=0.03), and high BMI (p=0.0006) were significant predictors of HS. Aspartate aminotransferase (p=0.0018) and alanine aminotransferase (p=0.012) were negatively correlated with liver attenuation. Reduced serum levels of alpha-1-antitrypsin may be a common factor of emphysema and HS.

CONCLUSION

LDCT can detect HS in asymptomatic participants with frequencies similar to previous reports. If liver attenuation is below 40HU and/or L/S ratio below 0.8, further evaluation of HS to the primary care physician or liver specialist is recommended.

Impact of Fatty Liver on Acute Pancreatitis Severity

Aim. Acute pancreatitis is typically a mild disease, but some patients develop severe courses. Fatty liver changes are seen in patients with acute pancreatitis, but its clinical significance has not been well-studied. We aimed to investigate the relationship between fatty liver and the severity of acute pancreatitis. Methods. Unenhanced CT images of patients with acute pancreatitis were retrospectively reviewed by a radiologist, and mean hepatic and splenic attenuation was measured in Hounsfield units (HU). Fatty liver was defined as mean hepatic/splenic HU < 1. Results. Among 200 patients, fatty liver was found in 67 (33.5%) and nonfatty liver in 133 (66.5%). Compared with patients without fatty liver, the severity of pancreatitis and levels of serum C-reactive protein were higher in fatty liver patients. The prevalence of local complications, persistent organ failure, and mortality were also higher in patients with fatty liver. Even after adjusting for age, sex, body mass index, and cause of pancreatitis, fatty liver was significantly associated with moderately severe or severe acute pancreatitis. Conclusions. Fatty liver may play a prognostic role in acute pancreatitis. Fatty liver could be incorporated into future predictive scoring models.

RNA sequence analysis of rat acute experimental pancreatitis with and without fatty liver: a gene expression profiling comparative study

Fatty liver (FL) is one of the risk factors for acute pancreatitis and is also indicative of a worse prognosis as compared to acute pancreatitis without fatty liver (AP). The aim of the present study was to analyze, at the hepatic level, the differentially expressed genes (DEGs) between acute pancreatitis with fatty liver (APFL) rats and AP rats. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analyses of these DEGs indicated that PPARα signalling pathway and fatty acid degradation pathway may be involved in the pathological process of APFL, which indicated that fatty liver may aggravate pancreatitis through these pathways. Moreover, the excessive activation of JAK/STAT signaling pathway and toll-like receptor signaling pathway was also found in APFL group as shown in heat map. In conclusion, the inhibition of PPARα signaling pathway and the fatty acid degradation pathway may lead to the further disorder of lipid metabolism, which can aggravate pancreatitis.