Development and Progression of Non-Alcoholic Fatty Liver Disease: The Role of Advanced Glycation End Products

Pathophysiology of diabetic hepatopathy and molecular mechanisms underlying the hepatoprotective effects of phytochemicals

Patients with diabetes are at risk for liver disorders including glycogen hepatopathy, non-alcoholic fatty liver disease, cirrhosis, and hepatic fibrosis. The pathophysiological mechanisms behind diabetic hepatopathy are complex, some of them include fatty acid accumulation, increased reactive oxygen species, increased advanced glycation end-products, hyperactivity of polyol pathways, increased apoptosis and necrosis, and promotion of fibrosis. A growing number of studies have shown that herbal extracts and their active phytochemicals have antihyperglycemic properties and beneficial effects on diabetic complications. The current review, for the first time, focused on herbal agents that showed beneficial effects on diabetic hepatopathy. For example, animal studies have shown that Moringa oleifera and Morus alba improve liver function in both type-1 and type-2 diabetes. Also, evidence from clinical trials suggests that Boswellia serrata, Juglans regia, Melissa officinalis, Portulaca oleracea, Silybum marianum, Talapotaka Churna, and Urtica dioica reduce serum liver enzymes in diabetic patients. The main active ingredient of these plants to protect the liver seems to be phenolic compounds such as niazirin, chlorogenic acid, resveratrol, etc. Mechanisms responsible for the hepatoprotective activity of herbal agents include improving glucose metabolism, restoring adipokines levels, antioxidant defense, and anti-inflammatory activity. Several signaling pathways are involved in hepatoprotective effects of herbal agents in diabetes, such as phosphoinositide 3-kinase, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase.

Inflammatory signaling in NASH driven by hepatocyte mitochondrial dysfunctions

Liver steatosis, inflammation, and variable degrees of fibrosis are the pathological manifestations of nonalcoholic steatohepatitis (NASH), an aggressive presentation of the most prevalent chronic liver disease in the Western world known as nonalcoholic fatty liver (NAFL). Mitochondrial hepatocyte dysfunction is a primary event that triggers inflammation, affecting Kupffer and hepatic stellate cell behaviour. Here, we consider the role of impaired mitochondrial function caused by lipotoxicity during oxidative stress in hepatocytes. Dysfunction in oxidative phosphorylation and mitochondrial ROS production cause the release of damage-associated molecular patterns from dying hepatocytes, leading to activation of innate immunity and trans-differentiation of hepatic stellate cells, thereby driving fibrosis in NASH.

A model of hepatic steatosis with declined viability and function in a liver-organ-on-a-chip

Nonalcoholic fatty liver disease (NAFLD) begins with benign steatosis caused by ectopic storage of triacylglycerols in the liver. Persistent steatosis, in combination with other genetic and environmental factors, leads to nonalcoholic steatohepatitis (NASH) characterized by functional impairment, inflammation, and fibrosis. However, it remains unclear how persistent steatosis directly contributes to the progression of NAFLD, which may represent a therapeutic target. The organ-on-a-chip (OOC) has emerged as a new culture platform to recapitulate human pathological conditions under which drug candidates can be screened. Here, we developed a simple OOC steatosis model using the Mimetas OrganoPlate with a human liver cell line, HepG2. Treating the HepG2 OOCs with fatty acid overload induced steatosis within 24 h. Moreover, persistent steatosis for 6 days impaired OOC viability and hepatic function, as measured by a WST-8 assay and albumin production, respectively. Lastly, the HepG2 OOCs were exposed to drugs being tested in clinical trials for NAFLD/NASH during the 6-day period. Pioglitazone improved the OOC viability while elafibranor reduced the steatosis in association with reduced viability and albumin production. In conclusion, we show that the HepG2 steatosis OOC model is a useful tool on which the efficacy and toxicity of various therapeutic candidates can be tested.

Aging, oxidative stress and degenerative diseases: mechanisms, complications and emerging therapeutic strategies

Aging accompanied by several age-related complications, is a multifaceted inevitable biological progression involving various genetic, environmental, and lifestyle factors. The major factor in this process is oxidative stress, caused by an abundance of reactive oxygen species (ROS) generated in the mitochondria and endoplasmic reticulum (ER). ROS and RNS pose a threat by disrupting signaling mechanisms and causing oxidative damage to cellular components. This oxidative stress affects both the ER and mitochondria, causing proteopathies (abnormal protein aggregation), initiation of unfolded protein response, mitochondrial dysfunction, abnormal cellular senescence, ultimately leading to inflammaging (chronic inflammation associated with aging) and, in rare cases, metastasis. RONS during oxidative stress dysregulate multiple metabolic pathways like NF-κB, MAPK, Nrf-2/Keap-1/ARE and PI3K/Akt which may lead to inappropriate cell death through apoptosis and necrosis. Inflammaging contributes to the development of inflammatory and degenerative diseases such as neurodegenerative diseases, diabetes, cardiovascular disease, chronic kidney disease, and retinopathy. The body's antioxidant systems, sirtuins, autophagy, apoptosis, and biogenesis play a role in maintaining homeostasis, but they have limitations and cannot achieve an ideal state of balance. Certain interventions, such as calorie restriction, intermittent fasting, dietary habits, and regular exercise, have shown beneficial effects in counteracting the aging process. In addition, interventions like senotherapy (targeting senescent cells) and sirtuin-activating compounds (STACs) enhance autophagy and apoptosis for efficient removal of damaged oxidative products and organelles. Further, STACs enhance biogenesis for the regeneration of required organelles to maintain homeostasis. This review article explores the various aspects of oxidative damage, the associated complications, and potential strategies to mitigate these effects.

Blood Endotoxin Levels as Biomarker of Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Growing evidence supports a role of gut-derived metabolites in nonalcoholic fatty liver disease (NAFLD), but the relation of endotoxin levels with gut permeability and NAFLD stage remains unclear. This systematic review with meta-analysis aims to provide further insights.

METHODS

PubMed, Embase, and Cochrane Library were searched for studies published until January 2022 assessing blood endotoxins in patients with NAFLD. Meta-analyses and univariate/multivariate meta-regression, as well as correlation analyses, were performed for endotoxin values and potential relationships to disease stage, age, sex, parameters of systemic inflammation, and metabolic syndrome, as well as liver function and histology.

RESULTS

Forty-three studies were included, of which 34 were used for meta-analyses. Blood endotoxin levels were higher in patients with simple steatosis vs liver-healthy controls (standardized mean difference, 0.86; 95% confidence interval, 0.62-1.11) as well as in patients with nonalcoholic steatohepatitis vs patients with nonalcoholic fatty liver/non-nonalcoholic steatohepatitis (standardized mean difference, 0.81; 95% confidence interval, 0.27-1.35; P = .0078). Consistently, higher endotoxin levels were observed in patients with more advanced histopathological gradings of liver steatosis and fibrosis. An increase of blood endotoxin levels was partially attributed to a body mass index rise in patients with NAFLD compared with controls. Nevertheless, significant increases of blood endotoxin levels in NAFLD retained after compensation for differences in body mass index, metabolic condition, or liver enzymes. Increases in blood endotoxin levels were associated with increases in C-reactive protein concentrations, and in most cases, paralleled a rise in markers for intestinal permeability.

CONCLUSION

Our results support blood endotoxin levels as relevant diagnostic biomarker for NAFLD, both for disease detection as well as staging during disease progression, and might serve as surrogate marker of enhanced intestinal permeability in NAFLD. Registration number in Prospero: CRD42022311166.

Dietary Nε-(carboxymethyl)lysine is a trigger of non-alcoholic fatty liver disease under high-fat consumption

The irreversible glycation of proteins produces advanced glycation end products (AGEs) which are triggered to bind the receptor for AGE (RAGE), thereby activating mitogen-activated protein kinase/nuclear factor-κB signaling pathway and stimulating proinflammatory cytokines, ultimately leading to chronic disorders. In this study, we focus the promoting effect of Nε-carboxymethyl-lysine (CML), one of the most dietary AGEs, on non-alcoholic fatty liver disease (NAFLD) and evaluated NAFLD-related biomarkers. Oxidative stress and hepatic steatosis were assessed in oleic acid (OA)-induced HepG2 cells. Using OA-induced HepG2 cells, we show that CML results in oxidative stress and steatosis and drives major changes in hepatic lipid metabolism. Administration of CML exacerbated NAFLD-related symptoms by increasing body and liver weight gain, serum alanine aminotransferase and lipid levels, and insulin resistance in mild high-fat diet-induced mice. Moreover, hepatic histological analysis data, such as staining, western blotting, and RNA-seq, indicate that CML aggravates NAFLD in association with activation of the de novo lipogenesis pathway, consistent with the in vitro assays. Our findings could contribute to model studies related to the prevention and treatment of NAFLD progression due to excessive consumption of dietary AGEs.

Plasma pentosidine as a useful biomarker of sarcopenia, low gait speed, and mortality in patients with cirrhosis

Purpose

The accumulation of advanced glycation end products (AGEs) is associated with various diseases and age-related impairments, including loss of muscle mass and function. We investigated the association between plasma pentosidine, which is one of the AGEs, and sarcopenia, low gait speed, and mortality in patients with cirrhosis.

Methods

This retrospective study divided 128 patients with cirrhosis into three groups by 25th and 75th quartiles of baseline plasma pentosidine levels: low (L)-, intermediate (I)-, and high (H)-pentosidine (Pen) groups. Sarcopenia was diagnosed following the Japan Society of Hepatology criteria. Low gait speed was defined as <0.8 m/s. The cumulative survival rates were compared between the three groups. Cox proportional hazards regression analysis was performed to identify independent factors associated with mortality.

Results

Of the 128 patients, 40 (31.3%) and 34 (26.6%) had sarcopenia and low gait speed, respectively. The prevalence of sarcopenia and low gait speed significantly increased stepwise with increasing plasma pentosidine levels, with the highest in the H-Pen group (59.4% [19/32] and 56.3% [18/32], respectively) and lowest in the L-Pen group (18.8% [6/32] and 6.3% [2/32], respectively). Multivariate analysis identified plasma pentosidine levels as a significant and independent factor associated with sarcopenia (odds ratio [OR], 1.07; p = 0.036) and low gait speed (OR, 1.06; p = 0.036), with the cutoff levels of 0.0792 μg/mL (sensitivity/specificity, 0.600/0.773) and 0.0745 μg/mL (sensitivity/specificity, 0.735/0.691), respectively. The cumulative survival rates were significantly lower in the H-Pen group than in the L-Pen (hazard ratio [HR], 11.7; p = 0.001) and I-Pen (HR, 4.03; p < 0.001) groups. Plasma pentosidine levels were identified as a significant and independent prognostic factor (HR, 1.07; p < 0.001).

Conclusion

Plasma pentosidine levels are associated with sarcopenia, low gait speed, and mortality and may serve as a useful surrogate biomarker for these clinical events in patients with cirrhosis.

Benefits of Combining Sonchus brachyotus DC. Extracts and Synbiotics in Alleviating Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease, commonly abbreviated to NAFLD, is a pervasive ailment within the digestive system, exhibiting a rising prevalence, and impacting individuals at increasingly younger ages. Those afflicted by NAFLD face a heightened vulnerability to the onset of profound liver fibrosis, cardiovascular complications, and malignancies. Currently, NAFLD poses a significant threat to human health, and there is no approved therapeutic treatment for it. Recent studies have shown that synbiotics, which regulate intestinal microecology, can positively impact glucolipid metabolism, and improve NAFLD-related indicators. Sonchus brachyotus DC., a Chinese herb, exhibits hepatoprotective and potent antioxidant properties, suggesting its potential therapeutic use in NAFLD. Our preclinical animal model investigation suggests that the synergy between Sonchus brachyotus DC. extracts and synbiotics is significantly more effective in preventing and treating NAFLD, compared to the isolated use of either component. As a result, this combination holds the potential to introduce a fresh and encouraging therapeutic approach to addressing NAFLD.

Comparison of the diagnostic performance of twelve noninvasive scores of metabolic dysfunction-associated fatty liver disease

BACKGROUND

The absence of distinct symptoms in the majority of individuals with metabolic dysfunction-associated fatty liver disease (MAFLD) poses challenges in identifying those at high risk, so we need simple, efficient and cost-effective noninvasive scores to aid healthcare professionals in patient identification. While most noninvasive scores were developed for the diagnosis of nonalcoholic fatty liver disease (NAFLD), consequently, the objective of this study was to systematically assess the diagnostic ability of 12 noninvasive scores (METS-IR/TyG/TyG-WC/TyG-BMI/TyG-WtHR/VAI/HSI/FLI/ZJU/FSI/K-NAFLD) for MAFLD.

METHODS

The study recruited eligible participants from two sources: the National Health and Nutrition Examination Survey (NHANES) 2017-2020.3 cycle and the database of the West China Hospital Health Management Center. The performance of the model was assessed using various metrics, including area under the receiver operating characteristic curve (AUC), net reclassification index (NRI), integrated discrimination improvement (IDI), decision curve analysis (DCA), and subgroup analysis.

RESULTS

A total of 7398 participants from the NHANES cohort and 4880 patients from the Western China cohort were included. TyG-WC had the best predictive power for MAFLD risk in the NHANES cohort (AUC 0.863, 95% CI 0.855-0.871), while TyG-BMI had the best predictive ability in the Western China cohort (AUC 0.903, 95% CI 0.895-0.911), outperforming other models, and in terms of IDI, NRI, DCA, and subgroup analysis combined, TyG-WC remained superior in the NAHANES cohort and TyG-BMI in the Western China cohort.

CONCLUSIONS

TyG-BMI demonstrated satisfactory diagnostic efficacy in identifying individuals at a heightened risk of MAFLD in Western China. Conversely, TyG-WC exhibited the best diagnostic performance for MAFLD risk recognition in the United States population. These findings suggest the necessity of selecting the most suitable predictive models based on regional and ethnic variations.

NIS2+™, an optimisation of the blood-based biomarker NIS4® technology for the detection of at-risk NASH: A prospective derivation and validation study

BACKGROUND & AIMS

NIS4® is a blood-based non-invasive test designed to effectively rule in/rule out at-risk non-alcoholic steatohepatitis (NASH), defined as non-alcoholic fatty liver disease activity score ≥4 and significant fibrosis (stage ≥2), among patients with metabolic risk factors. Robustness of non-invasive test scores across characteristics of interest including age, type 2 diabetes mellitus, and sex, and optimised analytical aspects are critical for large-scale implementation in clinical practice. We developed and validated NIS2+™, an optimisation of NIS4®, specifically designed to improve score robustness.

METHODS

A well-balanced training cohort (n = 198) included patients from the GOLDEN-505 trial. The validation (n = 684) and test (n = 2,035) cohorts included patients from the RESOLVE-IT trial. Well-matched subgroups were created to avoid potential confounding effects during modelling and analysis of score robustness. Models were trained using logistic regressions for at-risk NASH detection and compared using Bayesian information criteria. Performance of NIS2+™ was compared with that of NIS4®, Fibrosis-4, and alanine aminotransferase using area under the receiver operating characteristic curve, and robustness was analysed through score distribution.

RESULTS

Using the training cohort to compare all combinations of NIS4® biomarkers, NIS2 (miR-34a-5p, YKL-40) was identified as the best combination of parameters. To correct for the sex effect on miR-34a-5p (validation cohort), sex and sex ∗ miR-34a-5p parameters were added, creating NIS2+™. In the test cohort, NIS2+™ exhibited a statistically higher area under the receiver operating characteristic curve (0.813) vs. NIS4® (0.792; p = 0.0002), Fibrosis-4 (0.653; p <0.0001), and alanine aminotransferase (0.699; p <0.0001). NIS2+™ scores were not affected by age, sex, BMI, or type 2 diabetes mellitus status, providing robust clinical performances irrespective of patient characteristics.

CONCLUSION

NIS2+™ constitutes a robust optimisation of NIS4® technology for the detection of at-risk NASH.

IMPACT AND IMPLICATIONS

The development of non-invasive tests for accurate, large-scale detection of patients with at-risk non-alcoholic steatohepatitis (NASH; defined as NASH with non-alcoholic fatty liver disease activity score ≥4 and fibrosis stage ≥2) - who are at higher risk for disease progression and for developing liver-related life-threatening outcomes - is critical for identifying this patient population in the clinical setting and improving the screening process of NASH clinical trials. We report the development and validation of NIS2+™, a diagnostic test designed as an optimisation of NIS4® technology, a blood-based panel currently used to detect at-risk NASH in patients with metabolic risk factors. NIS2+™ showed improved performance for the detection of at-risk NASH compared with NIS4® and other non-invasive liver tests that was not impacted by patients' characteristics of interest, such as age, sex, type 2 diabetes mellitus, BMI, dyslipidaemia, and hypertension. This makes NIS2+™ a robust and reliable tool for the diagnosis of at-risk NASH among patients with metabolic risk factors, and an effective candidate for large-scale implementation in clinical practice and clinical trials.

The polysaccharides from Auricularia auricula alleviate non-alcoholic fatty liver disease via modulating gut microbiota and bile acids metabolism

The polysaccharides from Auricularia auricula (AAPs), containing a large number of O-acetyl groups that are related to the physiological and biological properties, seem to be potential prebiotics like other edible fungus polysaccharides. In the present study, therefore, the alleviating effects of AAPs and deacetylated AAPs (DAAPs, prepared from AAPs by alkaline treatment) on nonalcoholic fatty liver disease (NAFLD) induced by high-fat and high-cholesterol diet combined with carbon tetrachloride were investigated. The results revealed that both AAPs and DAAPs could effectively relieve liver injury, inflammation and fibrosis, and maintain intestinal barrier function. Both AAPs and DAAPs could modulate the disorder of gut microbiota and altered the composition of gut microbiota with enrichment of Odoribacter, Lactobacillus, Dorea and Bifidobacterium. Further, the alteration of gut microbiota, especially enhancement of Lactobacillus and Bifidobacterium, was contributed to the changes of bile acids (BAs) profile with increased deoxycholic acid (DCA). Farnesoid X receptor could be activated by DCA and other unconjugated BAs, which participated the BAs metabolism and alleviated the cholestasis, then protected against hepatitis in NAFLD mice. Interestingly, it was found that the deacetylation of AAPs negatively affected the anti-inflammation, thereby reducing the health benefits of A. auricula-derived polysaccharides.

NAFLD and nutraceuticals: a review of completed phase III and IV clinical trials

Background

Nonalcoholic Fatty Liver Disease (NAFLD) has become a significant public health concern, affecting approximately one-fourth of the population. Despite its prevalence, no FDA-approved drug treatments specifically target NAFLD.

Aim

To provide a review of clinical trials investigating the use of herbal remedies and dietary supplements in NAFLD management, utilizing the ClinicalTrials.gov database.

Methods

This review evaluates the current evidence by examining completed phase III and IV clinical trials registered on ClinicalTrials.gov. An exhaustive search was performed on April 17, 2023, using the terms "Nonalcoholic Fatty Liver Disease" and "NAFLD." Two independent reviewers appraised eligible trials based on pre-defined inclusion and exclusion criteria.

Results

An initial search yielded 1,226 clinical trials, with 12 meeting the inclusion criteria after filtration. The majority of trials focused on Omega-3 fatty acids (20.0%) and vitamin D (26.7%), followed by caffeine, chlorogenic acid, ginger, phosphatidylcholine, Trigonella Foenum-graecum seed extract, vitamin C, and vitamin E (each 6.7%). Most studies were Phase 3 (75.0%) and used a parallel assignment model (91.7%). Quadruple masking was the most prevalent technique (58.3%), and Iran was the leading country in terms of trial locations (25.0%). These interventions constitute two herbal interventions and nine supplement interventions.

Conclusion

This reveals a diverse range of nutraceuticals, with Omega-3 fatty acids and vitamin D being predominant in the management of NAFLD. The global distribution of trials highlights the widespread interest in these therapeutics. However, more rigorous, large-scale trials are needed to establish safety, efficacy, and optimal dosages.

AGER1 deficiency-triggered ferroptosis drives fibrosis progression in nonalcoholic steatohepatitis with type 2 diabetes mellitus

Hyperglycemia is an independent risk factor for the rapid progression of nonalcoholic steatohepatitis (NASH) to liver fibrosis with an incompletely defined mechanism. Ferroptosis is a novel form of programmed cell death that has been identified as a pathogenic mechanism in various diseases. However, the role of ferroptosis in the development of liver fibrosis in NASH with type 2 diabetes mellitus (T2DM) is unclear. Here, we observed the histopathological features of the progression of NASH to liver fibrosis as well as hepatocyte epithelial-mesenchymal transition (EMT) in a mouse model of NASH with T2DM and high-glucose-cultured steatotic human normal liver (LO2) cells. The distinctive features of ferroptosis, including iron overload, decreased antioxidant capacity, the accumulation of reactive oxygen species, and elevated lipid peroxidation products, were confirmed in vivo and in vitro. Liver fibrosis and hepatocyte EMT were markedly alleviated after treatment with the ferroptosis inhibitor ferrostatin-1. Furthermore, a decrease in the gene and protein levels of AGE receptor 1 (AGER1) was detected in the transition from NASH to liver fibrosis. Overexpression of AGER1 dramatically reversed hepatocyte EMT in high-glucose-cultured steatotic LO2 cells, whereas the knockdown of AGER1 had the opposite effect. The mechanisms underlying the phenotype appear to be associated with the inhibitory effects of AGER1 on ferroptosis, which is dependent on the regulation of sirtuin 4. Finally, in vivo adeno-associated virus-mediated AGER1 overexpression effectively relieved liver fibrosis in a murine model. Collectively, these findings suggest that ferroptosis participates in the pathogenesis of liver fibrosis in NASH with T2DM by promoting hepatocyte EMT. AGER1 could reverse hepatocyte EMT to ameliorate liver fibrosis by inhibiting ferroptosis. The results also suggest that AGER1 may be a potential therapeutic target for the treatment of liver fibrosis in patients with NASH with T2DM. Chronic hyperglycemia is associated with increased advanced glycation end products, resulting in the downregulation of AGER1. AGER1 deficiency downregulates Sirt4, which disturbs key regulators of ferroptosis (TFR-1, FTH, GPX4, and SLC7A11). These lead to increased iron uptake, decreasing the antioxidative capacity and enhanced lipid ROS production, ultimately leading to ferroptosis, which further promotes hepatocyte epithelial-mesenchymal transition and fibrosis progression in NASH with T2DM.

Histological features of non-alcoholic fatty liver disease revealed in response to mixed vehicle emission exposure and consumption of a high-fat diet in wildtype C57Bl/6 male mice

Non-alcoholic fatty liver disease (NAFLD) is currently plaguing the population at pandemic proportions and is expected to become more prevalent over the next decade. Recent epidemiological studies have demonstrated a correlation between the manifestation of NAFLD and ambient air pollution levels, which is exacerbated by other risk factors, such as diabetes, dyslipidemia, obesity, and hypertension. Exposure to airborne particulate matter has also been associated with inflammation, hepatic lipid accumulation, oxidative stress, fibrosis, and hepatocyte injury. While prolonged consumption of a high-fat (HF) diet is associated with NAFLD, little is known regarding the effects of inhaled traffic-generated air pollution, a ubiquitous environmental pollutant, on the pathogenesis of NAFLD. Therefore, we investigated the hypothesis that exposure to a mixture of gasoline and diesel engine emissions (MVE), coupled with the concurrent consumption of a HF diet, promotes the development of a NAFLD phenotype within the liver. Three-month-old male C57Bl/6 mice were placed on either a low-fat or HF diet and exposed via whole-body inhalation to either filtered (FA) air or MVE (30 µg PM/m³ gasoline engine emissions + 70 µg PM/m³ diesel engine emissions) 6 hr/day for 30 days. Histology revealed mild microvesicular steatosis and hepatocyte hypertrophy in response to MVE exposure alone, compared to FA controls, yielding a classification of "borderline NASH" under the criteria of the modified NAFLD active score (NAS) system. As anticipated, animals on a HF diet exhibited moderate steatosis; however, we also observed inflammatory infiltrates, hepatocyte hypertrophy, and increased lipid accumulation, with the combined effect of HF diet and MVE exposure. Our results indicate that inhalation exposure to traffic-generated air pollution initiates hepatocyte injury and further exacerbates lipid accumulation and hepatocyte injury induced by the consumption of a HF diet, thereby contributing to the progression of NAFLD-related pathologies.

Matrix disequilibrium in Alzheimer's disease and conditions that increase Alzheimer's disease risk

Alzheimer's Disease (AD) and related dementias are a leading cause of death globally and are predicted to increase in prevalence. Despite this expected increase in the prevalence of AD, we have yet to elucidate the causality of the neurodegeneration observed in AD and we lack effective therapeutics to combat the progressive neuronal loss. Throughout the past 30 years, several non-mutually exclusive hypotheses have arisen to explain the causative pathologies in AD: amyloid cascade, hyper-phosphorylated tau accumulation, cholinergic loss, chronic neuroinflammation, oxidative stress, and mitochondrial and cerebrovascular dysfunction. Published studies in this field have also focused on changes in neuronal extracellular matrix (ECM), which is critical to synaptic formation, function, and stability. Two of the greatest non-modifiable risk factors for development of AD (aside from autosomal dominant familial AD gene mutations) are aging and APOE status, and two of the greatest modifiable risk factors for AD and related dementias are untreated major depressive disorder (MDD) and obesity. Indeed, the risk of developing AD doubles for every 5 years after ≥ 65, and the APOE4 allele increases AD risk with the greatest risk in homozygous APOE4 carriers. In this review, we will describe mechanisms by which excess ECM accumulation may contribute to AD pathology and discuss pathological ECM alterations that occur in AD as well as conditions that increase the AD risk. We will discuss the relationship of AD risk factors to chronic central nervous system and peripheral inflammation and detail ECM changes that may follow. In addition, we will discuss recent data our lab has obtained on ECM components and effectors in APOE4/4 and APOE3/3 expressing murine brain lysates, as well as human cerebrospinal fluid (CSF) samples from APOE3 and APOE4 expressing AD individuals. We will describe the principal molecules that function in ECM turnover as well as abnormalities in these molecular systems that have been observed in AD. Finally, we will communicate therapeutic interventions that have the potential to modulate ECM deposition and turnover in vivo.

Dietary advanced glycation end products are associated with an increased risk of non-alcoholic fatty liver disease in Iranian adults

BACKGROUND

Dietary advanced glycation end products(AGEs) may contribute to increased inflammation and oxidative stress as risk factors for chronic diseases such as liver disease. In the current study, we aimed to examine the possible association of dietary AGEs with the odds of non-alcoholic fatty liver disease (NAFLD) in Iranian adults.

METHODS

A total of 675 participants (225 newly diagnosed NAFLD cases and 450 controls), aged  20-60 years, were recruited for this case-control study. Nutritional data were measured using a validated food frequency questionnaire, and dietary AGEs were determined for all participants. An ultrasound scan of the liver performed the detection of NAFLD in participants of the case group without alcohol consumption and other causes of hepatic disorders. We used logistic regression models, adjusted for potential confounders, to estimate the odds ratios(ORs) and 95% confidence interval(CI) of NAFLD across tertiles of dietary AGEs.

RESULTS

Mean ± SD age and body mass index of the participants were 38.13 ± 8.85 years and 26.85 ± 4.31 kg/m², respectively. The median(IQR) of dietary AGEs in participants was 3262(2472-4301). In the sex and age-adjusted model, the odds of NAFLD were increased across tertiles of dietary AGEs intake(OR:16.48;95%CI:9.57-28.40, P_trend<0.001). Also, in the final model, after controlling for confounding effects of BMI, smoking, physical activity, marital status, socio-economic status, and energy intake, the odds of NAFLD were increased across tertiles of dietary AGEs intake(OR:12.16; 95%CI:6.06-24.39, P_trend<0.001).

CONCLUSION

Our results showed that greater adherence to dietary pattern with high dietary AGEs intake was significantly related to increased odds of NAFLD.

Placebo Adverse Events in Non-alcoholic Steatohepatitis Clinical Trials: A Pooled Analysis of 2,944 Participants

INTRODUCTION

In the absence of an effective treatment for non-alcoholic steatohepatitis (NASH), a randomized, placebo-controlled trial (RCT) remains the current gold standard study design in NASH. As NASH is a largely asymptomatic disease, the side effects of potential therapies require careful evaluation, therefore a pooled rate of the adverse events (AEs) in placebo-treated patients serves as a useful comparator for safety. Therefore, we performed a systematic review and meta-analysis to estimate the rate of AEs among participants in the placebo arm of NASH RCTs.

METHODS

Medline, Embase and Cochrane Central Register of Controlled Trials were searched to include clinical trials in phase 2-4 NASH RCTs with placebo treatment arms. A pooled proportions of AEs were analyzed using a generalized linear mixed model with Clopper-Pearson intervals.

RESULTS

A total of 41 RCTs (2,944 participants on placebo) were included in this meta-analysis. A total of 68% (confidence interval [CI] 55%-77%) of participants on placebo experienced an AE, 7.8% (5.7%-10%) experienced serious AEs and 3.1% (CI: 1.9%-5.1%) experienced AEs leading to discontinuation. A significantly higher proportion of participants experienced serious AEs in phase 3 studies compared to in phase 2 studies ( P < 0.01) and in pharmaceutical funded studies as compared to studies which were federal-funded studies ( P < 0.01). An analysis of clinical trials evaluating bile acid modulating agents determined that 10% (CI: 5.5%-18%) of participants receiving placebo developed pruritus.

DISCUSSION

The present study summarizes the AEs with NASH placebo. Among participants in the placebo arm in NASH, two-third experienced an AE, and nearly 10% experienced a serious AE.

Fermented Soybean Paste Attenuates Biogenic Amine-Induced Liver Damage in Obese Mice

Biogenic amines are cellular components produced by the decarboxylation of amino acids; however, excessive biogenic amine production causes adverse health problems. The relationship between hepatic damage and biogenic amine levels in nonalcoholic fatty liver disease (NAFLD) remains unclear. In this study, mice were fed a high-fat diet (HFD) for 10 weeks to induce obesity, presenting early-stage of NAFLD. We administered histamine (20 mg/kg) + tyramine (100 mg/kg) via oral gavage for 6 days to mice with HFD-induced early-stage NAFLD. The results showed that combined histamine and tyramine administration increased cleaved PARP-1 and IL-1β in the liver, as well as MAO-A, total MAO, CRP, and AST/ALT levels. In contrast, the survival rate decreased in HFD-induced NAFLD mice. Treatment with manufactured or traditional fermented soybean paste decreased biogenically elevated hepatic cleaved PARP-1 and IL-1β expression and blood plasma MAO-A, CRP, and AST/ALT levels in HFD-induced NAFLD mice. Additionally, the biogenic amine-induced reduction in survival rate was alleviated by fermented soybean paste in HFD-induced NAFLD mice. These results show that biogenic amine-induced liver damage can be exacerbated by obesity and may adversely affect life conservation. However, fermented soybean paste can reduce biogenic amine-induced liver damage in NAFLD mice. These results suggest a beneficial effect of fermented soybean paste on biogenic amine-induced liver damage and provide a new research perspective on the relationship between biogenic amines and obesity.

PNPLA3 genotypes modify the adverse effect of the total energy intake on high-risk nonalcoholic steatohepatitis development

BACKGROUND

The relationship between diet and risk genotypes in nonalcoholic steatohepatitis (NASH) development and fibrosis progression in patients with nonalcoholic fatty liver disease (NAFLD) remains unclear.

OBJECTIVE

We aimed to investigate the effects of diet on NASH development and fibrosis progression in patients with NAFLD stratified by the PNPLA3 genotype.

METHODS

We performed a prospective study in a cohort of patients with biopsy-confirmed NAFLD. Histologic deterioration was obtained using serial transient elastography at every 1 or 2 y. The primary outcome was fibrosis progression, and the secondary outcome was development of high-risk NASH, defined as FibroScan-aspartate aminotransferase score ≥0.67 during the follow-up of patients with nonalcoholic fatty liver at the baseline. Dietary intake was evaluated using a semiquantitative food frequency questionnaire.

RESULTS

The primary outcome was observed in 42 (29.0%) of the 145 patients during a median follow-up of 49 mo; neither the total energy intake nor each macronutrient intake significantly affected the primary outcome occurrence. Conversely, the total energy intake (HR per 1-SD: 3.03; 95% CI: 1.31, 7.01) and the PNPLA3 rs738409 genotype [HR per 1 risk allele (G): 2.06; 95% CI: 1.11, 3.83)] were independent risk factors for high-risk NASH. The significant interaction between the total energy intake and PNPLA3 genotype was noted in developing high-risk NASH (P = 0.044). As the number of PNPLA3 risk alleles decreased, the effect of the total energy intake on high-risk NASH increased; the HR per 1-SD increment in total energy intake was 1.52 (95% CI: 0.42, 5.42), 3.54 (95% CI: 1.23, 10.18), and 8.27 (95% CI: 1.20, 57.23) for the GG, CG, and CC genotypes, respectively.

CONCLUSIONS

The total energy intake adversely affected the development of high-risk NASH in patients with biopsy-confirmed NAFLD. The effect was more prominent in patients without the PNPLA3 risk allele, highlighting the importance of personalized dietary interventions in NAFLD treatment.

Efficacy of curcumin plus piperine co-supplementation in moderate-to-high hepatic steatosis: A double-blind, randomized, placebo-controlled clinical trial

Non-alcoholic Fatty Liver Disease (NAFLD) is a global health problem that can progress to steatohepatitis and cirrhosis. The aim of this study was to determine the effect of curcumin + piperine on cardiometabolic risk factors, as well as hepatic steatosis and fibrosis in NAFLD patients with moderate-to-high hepatic steatosis. Patients diagnosed with moderate-to-high NAFLD by liver sonography were randomized to either curcumin + piperine (500 mg/day curcumin plus 5 mg/day piperine) for 12 weeks (n = 30) or placebo groups (n = 30). Liver fibroscan, anthropometric measurements, dietary intake, physical activity, blood pressure, lipid profile, high-sensitivity C-reactive protein, fasting blood glucose (FBG), and liver enzymes were assessed at baseline and after 12 weeks of follow-up. Intention-to-treat analysis was undertaken. Curcumin + piperine decreased waist circumference (p = 0.026), systolic blood pressure (p = 0.001), total cholesterol (p = 0.004), low-density lipoprotein-cholesterol (p = 0.006), FBG (p = 0.002), alanine transaminase (p = 0.007) and aspartate transaminase (p = 0.012) compared with placebo. However, fibroscan measurement did not differ between curcumin + piperine and placebo groups (p > 0.05). Fibroscan measurement as a marker of NAFLD improvement did not differ after 12 weeks of curcumin + piperine; however, curcumin + piperine may be considered as an adjunct therapy to improve anthropometric measures, blood pressure, lipid profile, blood glucose, and liver function in NAFLD patients.

Contribution of Trimethylamine N-Oxide (TMAO) to Chronic Inflammatory and Degenerative Diseases

Trimethylamine N-oxide (TMAO) is a metabolite produced by the gut microbiota and has been mainly associated with an increased incidence of cardiovascular diseases (CVDs) in humans. There are factors that affect one's TMAO level, such as diet, drugs, age, and hormones, among others. Gut dysbiosis in the host has been studied recently as a new approach to understanding chronic inflammatory and degenerative diseases, including cardiovascular diseases, metabolic diseases, and Alzheimer's disease. These disease types as well as COVID-19 are known to modulate host immunity. Diabetic and obese patients have been observed to have an increase in their level of TMAO, which has a direct correlation with CVDs. This metabolite is attributed to enhancing the inflammatory pathways through cholesterol and bile acid dysregulation, promoting foam cell formation. Additionally, TMAO activates the transcription factor NF-κB, which, in turn, triggers cytokine production. The result can be an exaggerated inflammatory response capable of inducing endoplasmic reticulum stress, which is responsible for various diseases. Due to the deleterious effects that this metabolite causes in its host, it is important to search for new therapeutic agents that allow a reduction in the TMAO levels of patients and that, thus, allow patients to be able to avoid a severe cardiovascular event. The present review discussed the synthesis of TMAO and its contribution to the pathogenesis of various inflammatory diseases.

G protein-coupled receptor 39 alleviates mitochondrial dysfunction and hepatocyte lipid accumulation via SIRT1/Nrf2 signaling

OBJECTIVE

Data in the GEO database (GSE63067) showed that G protein-coupled receptor 39 (GPR39) was down-regulated in tissues from patients with non-alcoholic fatty liver disease (NAFLD). It was intended to explore the mechanism of GPR39 in NAFLD.

METHODS

HepG2 cells were treated with a mixture of oleic acid and palmitic acid (OA/PA) to mimic NAFLD cell models. The level of GPR39 and the functions of GPR39 on cellular oxidative stress, lipid accumulation, the SIRT1/Nrf2 signaling and mitochondrial dysfunction were assessed. To verify the mediation of the SIRT1 signaling pathway in GPR39 regulation, cells were subjected to SIRT1 inhibitor EX-527 treatment. Afterwards, the abovementioned aspects of cells were all determined.

RESULTS

GPR39 presented a downward trend in response to OA/PA. GPR39 overexpression could suppress oxidative stress, lipid accumulation and activate the SIRT1/Nrf2 signaling. GPR39 overexpression likewise alleviated mitochondrial dysfunction, whereas EX-527 treatment disturbed the effects of GPR39 overexpression on these aspects.

CONCLUSION

The present study found that GPR39 reduced oxidative stress and maintained mitochondrial homeostasis in a cellular model of NAFLD, a process mediated by SIRT1/Nrf2 signaling.

Terpenoids: Natural Compounds for Non-Alcoholic Fatty Liver Disease (NAFLD) Therapy

Natural products have been the most productive source for the development of drugs. Terpenoids are a class of natural active products with a wide range of pharmacological activities and therapeutic effects, which can be used to treat a variety of diseases. Non-alcoholic fatty liver disease (NAFLD), a common metabolic disorder worldwide, results in a health burden and economic problems. A literature search was conducted to obtain information relevant to the treatment of NAFLD with terpenoids using electronic databases, namely PubMed, Web of Science, Science Direct, and Springer, for the period 2011-2021. In total, we found 43 terpenoids used in the treatment of NAFLD. Over a dozen terpenoid compounds of natural origin were classified into five categories according to their structure: monoterpenoids, sesquiterpenoids, diterpenoids, triterpenoids, and tetraterpenoids. We found that terpenoids play a therapeutic role in NAFLD, mainly by regulating lipid metabolism disorder, insulin resistance, oxidative stress, and inflammation. The AMPK, PPARs, Nrf-2, and SIRT 1 pathways are the main targets for terpenoid treatment. Terpenoids are promising drugs and will potentially create more opportunities for the treatment of NAFLD. However, current studies are restricted to animal and cell experiments, with a lack of clinical research and systematic structure-activity relationship (SAR) studies. In the future, we should further enrich the research on the mechanism of terpenoids, and carry out SAR studies and clinical research, which will increase the likelihood of breakthrough insights in the field.

Excessive gluconeogenesis causes the hepatic insulin resistance paradox and its sequelae

Background

Hepatic insulin signaling suppresses gluconeogenesis but promotes de novo lipid synthesis. Paradoxically, hepatic insulin resistance (HIR) enhances both gluconeogenesis and de novo lipid synthesis. Elucidation of the etiology of this paradox, which participates in the pathogenesis of non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, the metabolic syndrome and hepatocellular carcinoma, has not been fully achieved.

Scope of review

This article briefly outlines the previously proposed hypotheses on the etiology of the HIR paradox. It then discusses literature consistent with an alternative hypothesis that excessive gluconeogenesis, the direct effect of HIR, is responsible for the aberrant lipogenesis. The mechanisms involved therein are explained, involving de novo synthesis of fructose and uric acid, promotion of glutamine anaplerosis, and induction of glucagon resistance. Thus, gluconeogenesis via lipogenesis promotes hepatic steatosis, a component of NAFLD, and dyslipidemia. Gluconeogenesis-centred mechanisms for the progression of NAFLD from simple steatosis to non-alcoholic steatohepatitis (NASH) and fibrosis are suggested. That NAFLD often precedes and predicts type 2 diabetes is explained by the ability of lipogenesis to cushion against blood glucose dysregulation in the earlier stages of NAFLD.

Major conclusions

HIR-induced excessive gluconeogenesis is a major cause of the HIR paradox and its sequelae. Such involvement of gluconeogenesis in lipid synthesis rationalizes the fact that several types of antidiabetic drugs ameliorate NAFLD. Thus, dietary, lifestyle and pharmacological targeting of HIR and hepatic gluconeogenesis may be a most viable approach for the prevention and management of the HIR-associated network of diseases.

Alcoholic Liver Disease Is Associated with Elevated Plasma Levels of Novel Advanced Glycation End-Products: A Preliminary Study

Elucidating the biochemical mechanisms associated with the progression of alcoholic liver disease (ALD) to more advanced stages such as alcoholic hepatitis (AH) remains an important clinical and scientific challenge. Several hypotheses point to the involvement of advanced glycation end-products (AGEs) in alcohol-associated liver injuries. Recently, we determined the structure of a synthetic, melibiose-derived AGE (MAGE), which was an analog of the novel AGE subgroup AGE10. The primary objective of our study was to determine whether AGE10 was associated with alcoholic hepatitis. The secondary objective was to provide a diagnostic accuracy of AGE10 in AH. To achieve this objective, we examined the plasma levels of AGE10 in 65 healthy individuals and 65 patients with AH. The AGE10 level was measured using a competitive ELISA. Our study confirmed that patients with AH had significantly higher plasma concentrations of AGE10 compared with healthy controls (184.5 ± 71.1 μg/mL and 123.5 ± 44.9 μg/mL, respectively; p < 0.001). In addition, AGE10 showed an acceptable performance as a diagnostic marker of AH, with an AUC of 0.78. In conclusion, AH was associated with elevated levels of novel advanced glycation end-product AGE10.

Discussing the role of circular RNA in the pathogenesis of non-alcoholic fatty liver disease and its complications

Circular RNAs (circRNAs) are class of non-coding RNA, which are characterized by a covalently closed loop structure. Functionally they can act on cellular physiology, notably by sponging microRNAs (miR), regulating gene expression or interacting with binding protein. To date, circRNAs might represent an interesting, underexploited avenue for new target discovery for therapeutic applications, especially in the liver. The first characteristic of non-alcoholic fatty liver disease (NAFLD) is hepatic cholesterol accumulation, followed by its advanced form of the affection, nonalcoholic steatohepatitis (NASH), due to the occurrence of lobular inflammation, irreversible fibrosis, and in some cases hepatocellular carcinoma (HCC). Therefore, studies have investigated the importance of the dysregulation of circRNAs in the onset of metabolic disorders. In this review, we summarize the potential role of circRNAs in the development of metabolic diseases associated with the liver such as NAFLD or NASH, and their potential to become therapeutic strategies for these pathologies.

Combination of LC-Q-TOF-MS/MS, network pharmacology, and nanoemulsion approaches identifies active compounds of two Artemisia species responsible for tackling early diabetes-related metabolic complications in the liver

INTRODUCTION

The chronicity of advanced glycation end-products (AGEs) imparts various damages resulting in metabolic dysfunction and diseases involving inflammation and oxidative stress. The use of plant extracts is of high interest in complementary medicine. Yet, extracts are multicomponent mixtures, and difficult to pinpoint their exact mechanism.

OBJECTIVES

We hypothesise that network pharmacology and bioinformatics can help experimental findings depict the exact active components and mechanism of action by which they induce their effects. Additionally, the toxicity and variability can be lowered and standardised with proper encapsulation methods.

METHODOLOGY

Here, we propose the formulation of phytoniosomes encapsulating two Artemisia species (Artemisia dracunculus and Artemisia absinthium) to mitigate AGEs and their induced cell redox dysregulation in the liver. Extracts from different solvents were identified via liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS/MS). Phytoniosomes were explored for their anti-glycating effect and modulation of AGE-induced damages in THLE-2 liver cells. Network pharmacology tools were used to identify possible targets and signalling pathways implicated.

RESULTS

Data demonstrated that A. absinthium phytoniosomes had a significant anti-AGE effect comparable to reference molecules and higher than A. dracunculus. They were able to restore cell dysfunction through the restoration of tumour necrosis alpha (TNF-α), interleukin 6 (IL-6), nitric oxide, and total antioxidant capacity. Phytoniosomes were able to protect cells from apoptosis by decreasing caspase 3 activity. Network pharmacology and bioinformatic analysis confirmed the induction of the effect via Akt-PI3K-MAPK and AGE-RAGE signalling pathways through quercetin and luteolin actions.

CONCLUSION

The current report highlights the potential of Artemisia phytoniosomes as strong contenders in AGE-related disease therapy.

Accuracy of Ultrasonography vs. Elastography in Patients With Non-alcoholic Fatty Liver Disease: A Systematic Review

Ultrasonography and elastography are the most widely used imaging modalities for diagnosing non-alcoholic fatty liver disease. This study aimed to assess and compare the diagnostic accuracy in patients with non-alcoholic fatty liver disease/non-alcoholic steatohepatitis. This systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search was done for the past seven years using Pubmed, Pubmed Central, Cochrane, and Google Scholar databases on Jun 29, 2022. Studies were included based on the following predefined criteria: observational studies, randomized controlled trial (RCT), comparative studies, studies using liver biopsy or MRI proton density fat fraction (MRI PDFF) as a reference standard, ultrasonography, and elastography with measures of their diagnostic accuracy like sensitivity (SN), specificity (SP), area under the receiver operating characteristic (AUROC) curve, and English language. The data were extracted on a predefined template. The final twelve eligible studies were assessed using the quality assessment of diagnostic accuracy tool (QUADS-2). Most studies focused on elastography techniques, and the remaining focused on quantitative ultrasonography methods like the controlled attenuation parameter (CAP) and attenuation coefficient (AC). Only one study was available for the evaluation of qualitative ultrasonography. MRI was generally found superior to other diagnostic tests for determining liver stiffness through magnetic resonance elastography (MRE) and steatosis through MRI PDFF. Data assessing the comparative diagnostic accuracy of the two tests were inconclusive.

Cyclodipeptides: From Their Green Synthesis to Anti-Age Activity

Cyclodipeptides (CDPs) or diketopiperazines (DKPs) are often found in nature and in foodstuff and beverages and have attracted great interest for their bioactivities, biocompatibility, and biodegradability. In the laboratory, they can be prepared by green procedures, such as microwave-assisted cyclization of linear dipeptides in water, as performed in this study. In particular, five CDPs were prepared and characterized by a variety of methods, including NMR and ESI-MS spectroscopies and single-crystal X-ray diffraction (XRD), and their cytocompatibility and anti-aging activity was tested in vitro, as well as their ability to penetrate the different layers of the skin. Although their mechanism of action remains to be elucidated, this proof-of-concept study lays the basis for their future use in anti-age cosmetic applications.

Atherogenic Index of Plasma in Non-Alcoholic Fatty Liver Disease: Systematic Review and Meta-Analysis

(1) Background: Approximately a billion people worldwide are affected by NAFLD, which places a high clinical burden and financial cost on society. Liver biopsy is the gold standard for diagnosing NAFLD, but its invasivity limits the early diagnosis of NAFLD. Hence, it is important to look for alternate techniques in detecting and diagnosing NAFLD. NAFLD is associated with atherosclerosis. The purpose of this study was to assess the effectiveness of the atherogenic index of plasma (AIP) as a non-invasive modality for predicting NAFLD. (2) Methods: A search using electronic databases PubMed, EMBASE, and Scopus was carried out to find observational studies, looking at research that had been published up until the date of 11 May 2022. The included studies' quality, risk of bias, and internal validity were evaluated using the QUADAS-2 quality assessment tool. The key summary outcomes were the mean difference (MD) and area under the curve (AUC). (3) Results: A total of eight studies (81,178 participants) were included in our review, while 17% of the included participants had NAFLD. A sex distribution of 57.8% men and 42.2% women was observed. The AIP between NAFLD and the controls was not significant (MD 0.212 [95% CI 0.231-0.655]). A significant MD in AIP between the males and females with NAFLD was observed (MD 0.246 [95% CI 0.098-0.395]). The AIP predicted NAFLD with an AUC of 0.764 as well as in males (AUC 0.761) and females (AUC 0.733). (4) Conclusions: There was a substantial MD in the AIP between both sexes, but there was no significant difference in the AIP values between patients with NAFLD and the controls. The AIP is a reliable biomarker for the diagnosis of NAFLD since its ability to predict the development of NAFLD was comparable to that of the other biomarkers.

Identification of a potent NAFLD drug candidate for controlling T2DM-mediated inflammation and secondary damage in vitro and in vivo

Accumulation of glucose/sugar results in the formation of reactive di-carbonyl compounds such as MGO and GO that interact with several amino acids and proteins to form toxic advanced glycation end products (AGEs). Induction of AGEs breakdown can control symptoms and severity in T2DM and other related complications like NAFLD where AGEs are the key players. Therefore, an AGE cross-link breaker has been suggested for preventing the onset/progression of NAFLD. In this study, we reported novel synthetic naphthalene-2-acyl thiazolium derivatives (KHAGs). Among synthesized KHAG derivatives, we observed that a novel KHAG-04, a 1,4-dimethoxynaphthalen-2-acyl thiazolium salt which is an analog of alagebrium, dramatically cleaves MGO/GO-AGE cross-links, and it also inhibited inflammation by lowering the level of nitric oxide production and IL-1β and TNF-α secretion in LPS and/or MGO-AGE–activated macrophage. Moreover, it also reduced FFA and MGO-AGE–induced lipogenesis in Hep-G2 cells. In mice, KHAG-04 significantly reduced the level of glyoxal in the liver, which was induced by DMC. Furthermore, KHAG-04 treatment significantly reduced blood glucose levels, lipid accumulation, and inflammation in the NAFLD/T2DM animal model. Novel KHAG-04–mediated induction of AGEs breakdown could be the possible reason for its anti-inflammatory, antihyperglycemic, and anti-lipidemic effects in cells and NAFLD in the T2DM animal model, respectively. Further research might explore the pharmacological efficacy and usefulness and consider the ability of this compound in the treatment strategy against various models of NAFLD in T2DM where MGO/GO-AGEs play a key role in the pathogenesis.

Artemisia alleviates AGE-induced liver complications via MAPK and RAGE signaling pathways modulation: a combinatorial study

Artemisia herba-alba (AHA) is a traditionally used plant to treat various diseases, including diabetes and metabolic dysfunctions. Plant extracts are generally explored empirically without a deeper assessment of their mechanism of action. Here, we describe a combinatorial study of biochemical, molecular, and bioinformatic (metabolite-protein pharmacology network) analyses to elucidate the mechanism of action of AHA and shed light on its multilevel effects in the treatment of diabetes-related advanced glycation end-products (AGE)-induced liver damages. The extract's polyphenols and flavonoids content were measured and then identified via LC-Q-TOF-MS/MS. Active compounds were used to generate a metabolite-target interaction network via Swiss Target Prediction and other databases. The extract was tested for its antiglycation and aggregation properties. Next, THLE-2 liver cells were challenged with AGEs, and the mechanistic markers were measured [TNF-α, IL-6, nitric oxide, total antioxidant capacity, lipid peroxidation (LPO), and caspase 3]. Metabolite and network screening showed the involvement of AHA in diabetes, glycation, liver diseases, aging, and apoptosis. Experimental confirmation showed that AHA inhibited protein modification and AGE formation. Additionally, AHA reduced inflammatory mediators (IL-6, TNFα), oxidative stress markers (NO, LPO), and apoptosis (Caspase 3). On the other hand, cellular total antioxidant capacity was restored to normal levels. The combinatorial study showed that AHA regulates AGE-induced liver damages through MAPK-AKT and AGE-RAGE signaling pathways. This report highlights the combination of experimental and network pharmacology for the exact elucidation of AHA mechanism of action as a multitarget option in the therapy of diabetes and AGEs-related diseases.

Angiotensin Converting Enzyme-2 Therapy Improves Liver Fibrosis and Glycemic Control in Diabetic Mice With Fatty Liver

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and is frequently associated with type 2 diabetes. However, there is no specific medical therapy to treat this condition. Angiotensin-converting enzyme 2 (ACE2) of the protective renin angiotensin system generates the antifibrotic peptide angiotensin-(1-7) from profibrotic angiotensin II peptide. In this study, we investigated the therapeutic potential of ACE2 in diabetic NAFLD mice fed a high-fat (20%), high-cholesterol (2%) diet for 40 weeks. Mice were given a single intraperitoneal injection of ACE2 using an adeno-associated viral vector at 30 weeks of high-fat, high-cholesterol diet (15 weeks after induction of diabetes) and sacrificed 10 weeks later. ACE2 significantly reduced liver injury and fibrosis in diabetic NAFLD mice compared with the control vector injected mice. This was accompanied by reductions in proinflammatory cytokine expressions, hepatic stellate cell activation, and collagen 1 expression. Moreover, ACE2 therapy significantly increased islet numbers, leading to an increased insulin protein content in β-cells and plasma insulin levels with subsequent reduction in plasma glucose levels compared with controls. Conclusion: We conclude that ACE2 gene therapy reduces liver fibrosis and hyperglycemia in diabetic NAFLD mice and has potential as a therapy for patients with NAFLD with diabetes.

A promising antifibrotic drug, pyridoxamine attenuates thioacetamide-induced liver fibrosis by combating oxidative stress, advanced glycation end products, and balancing matrix metalloproteinases

Liver fibrosis is a common chronic hepatic disease. This study was done to examine the effect of pyridoxamine against thioacetamide-induced hepatic fibrosis. Animals were divided into four groups (1) control group; (2) Thioacetamide group (200 mg/kg, i.p.) twice a week for eight weeks; (3) Pyridoxamine-treated group treated with pyridoxamine (100 mg/kg/day, i.p.) for eight weeks; (4) Thioacetamide and pyridoxamine group, in which pyridoxamine was given (100 mg/kg/day, i.p.) during thioacetamide injections. Thioacetamide treatment resulted in hepatic dysfunction manifested by increased serum levels of bilirubin, gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Oxidative stress was noted by increased hepatic lipid peroxidation and decreased glutathione (GSH). Increased concentrations of total nitrite/nitrate, advanced glycation end products (AGEs), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), matrix metalloproteinases (MMP-2&9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were noticed in hepatic tissues. Immunostaining sections also revealed overexpression of MMP-2, MMP-9 and collagen IV. Liver fibrosis was confirmed by severe histopathological changes. Pyridoxamine improved the assessed parameters. Moreover, histopathological and immunohistological studies supported the ability of pyridoxamine to reduce liver fibrosis. The findings of the present study provide evidence that pyridoxamine is a novel target for the treatment of liver fibrosis.

Liraglutide inhibits receptor for advanced glycation end products (RAGE)/reduced form of nicotinamide-adenine dinucleotide phosphate (NAPDH) signaling to ameliorate non-alcoholic fatty liver disease (NAFLD) in vivo and vitro

The study was designed to investigate the effects of liraglutide and reveal its action mechanism associated with RAGE/NAPDH in NAFLD. The liver tissue was collected for HE, Masson, and ROS staining. Apoptosis levels were detected through TUNEL staining and ROS levels were evaluated through ROS staining. The expression levels of c-Jun N-terminal kinase (JNK) and transforming growth factor-β (TGF-β) were detected through Western blot. JNK and the expression of Collagenα1, Collagenα2 and connective tissue growth factor (CTGF) were detected through RT-qPCR and Western blot and the expression in mouse liver stellate cells (JS-1) cells were evaluated through immunofluorescence staining. We detected the effects of liraglutide on NAFLD in high-fat diet (HFD)-fed mice. Liraglutide treatment improved bridging fibrosis and liver function, as well as lessening ROS levels and the protein levels of RAGE, NOX1, NOX2 and NOX4. In PA and H2O2-induced AML12 cells, liraglutide treatment was able to decrease cell apoptosis, ROS levels and the levels of inflammatory factors including tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, while it effects were reversed by the induction of RAGE overexpression or NOX2 overexpression. In JS-1 cells treated with medium culturing AML12 cells, liraglutide markedly suppressed cell proliferation and activation, while RAGE overexpression or NOX2 overexpression blunted these effects of liraglutide. Taken together, liraglutide exerts a protective role in improving liver injury caused by HFD, which could be related to decreased apoptosis and oxidative stress of liver cells, as well as decreased proliferation and activation of hepatic stellate cells through RAGE/NOX2.

MAFLD/NAFLD Biopsy-Free Scoring Systems for Hepatic Steatosis, NASH, and Fibrosis Diagnosis

Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as nonalcoholic fatty liver disease, is the most prevalent liver disorder worldwide. Historically, its diagnosis required biopsy, even though the procedure has a variable degree of error. Therefore, new non-invasive strategies are needed. Consequently, this article presents a thorough review of biopsy-free scoring systems proposed for the diagnosis of MAFLD. Similarly, it compares the severity of the disease, ranging from hepatic steatosis (HS) and nonalcoholic steatohepatitis (NASH) to fibrosis, by contrasting the corresponding serum markers, clinical associations, and performance metrics of these biopsy-free scoring systems. In this regard, defining MAFLD in conjunction with non-invasive tests can accurately identify patients with fatty liver at risk of fibrosis and its complications. Nonetheless, several biopsy-free scoring systems have been assessed only in certain cohorts; thus, further validation studies in different populations are required, with adjustment for variables, such as body mass index (BMI), clinical settings, concomitant diseases, and ethnic backgrounds. Hence, comprehensive studies on the effects of age, morbid obesity, and prevalence of MAFLD and advanced fibrosis in the target population are required. Nevertheless, the current clinical practice is urged to incorporate biopsy-free scoring systems that demonstrate adequate performance metrics for the accurate detection of patients with MAFLD and underlying conditions or those with contraindications of biopsy.

Association Between Triglyceride-Glucose Index and Risk of Metabolic Dysfunction-Associated Fatty Liver Disease: A Cohort Study

OBJECTIVE

Insulin resistance (IR) is a major factor involved in the pathogenesis of metabolic dysfunction-associated fatty liver disease (MAFLD). Triglyceride-glucose (TyG) index, an easily detected surrogate marker of IR, has not been explored sufficiently on its relationship with incident MAFLD risk. This study sought to investigate the association of baseline TyG index with the risk of MAFLD in a Chinese cohort.

METHODS

This health check-up cohort was constructed with eligible 2056 Chinese from a community. The TyG index was calculated as ln (fasting triglyceride [mg/dL]×fasting glucose [mg/dL]/2). Cox proportion hazard models were used to evaluate the longitudinal association between baseline TyG index and the risk of MAFLD.

RESULTS

During an average follow-up of 2.5 ± 0.5 years, about 12.8% of the subjects developed MAFLD, and the incidence of MAFLD trended to increase with the quartile TyG index (P _trend < 0.05). After adjusting for all confounders, TyG index was independently correlated with the risk of incident MAFLD (HR = 1.784, 95% CI = 1.383-2.302, P < 0.001), and the risk of MAFLD in the highest quartile of TyG index was two times higher than that in the lowest quartile (95% CI = 1.377-2.992, P = 0.001). The restricted cubic spline analysis showed that the relationship between TyG index and the risk of MAFLD was linear in males (P for total < 0.001; P for non-linearity = 0.746), but nonlinear in females (P for non-linearity = 0.040).

CONCLUSION

A high baseline TyG index was independently associated with a high risk of incident MAFLD, and we might develop the strategy of MAFLD prevention based on the TyG index.

Pharmacodynamic Evaluation of the Gexia Zhuyu Decoction in the Treatment of NAFLD and the Molecular Mechanism Underlying the TRPM4 Pathway Regulation

Nonalcoholic fatty liver disease (NAFLD) is a clinicopathological syndrome of abnormal lipid deposition in the liver mediated by nonalcohol intake. The Gexia Zhuyu decoction, a classic traditional Chinese medicine compound, is widely used in the clinical treatment of NAFLD. However, its specific efficacy and underlying mechanisms have not been elucidated yet. This study aimed to quantitatively evaluate the efficacy of the Gexia Zhuyu decoction using pharmacodynamics and to explore its molecular mechanisms in conjunction with proteomics. High-fat diets and methionine choline-deficient diets were used to induce various NAFLD progression stages in mouse models. The effects of oral Gexia Zhuyu decoction administration on NAFLD were evaluated by measuring the serum and liver indicators of the treated mice before and after drug intervention and by comparing the changes in liver tissue. Liver TRPM4 mRNA and protein levels were measured using reverse transcription-polymerase chain reaction and Western blotting, respectively. Experimental data showed that serum ALT, AST, and liver triglyceride (TG) levels in each disease stage group of drug intervention mice decreased, and high-density lipoprotein (HDL) and superoxide dismutase (SOD) levels increased. Liver TG levels decreased after drug intervention in the liver fibrosis mice, but serum TG levels increased. Furthermore, cellular fatty changes, inflammatory changes, and fibrous tissue proliferation were all relieved. The TRPM4 protein and mRNA levels in the liver tissue were decreased, and the microRNA (miRNA)-24 expression was increased. The Gexia Zhuyu decoction has a clear therapeutic effect at each stage of NAFLD. It likely acts by altering miRNA-24 expression and regulating the target TRPM4 protein pathway to achieve NAFLD treatment.

Increased Urinary Levels of Pentosidine Measured by a Newly Developed Enzyme-Linked Immunosorbent Assay Are Independently Correlated with Fracture After Fall

Although we have found that increased serum levels of glyceraldehyde-derived advanced glycation end products (AGEs) are associated with numerous aging-related disorders, it remains unclear which structurally distinct AGEs could be a reliable biomarker of the healthy life-threatening disorders. Since pentosidine is produced by glyceraldehyde, we measured here urinary pentosidine levels with a newly developed enzyme-linked immunosorbent assay (ELISA) kit, which requires no pretreatment with acid hydrolysis and heat, and examined their correlations with geriatric syndrome, such as musculoskeletal disease, frailty, and cognitive impairment, in a general population. Multiple regression analysis revealed that female, age, history of fracture after fall, and taking medication for diabetes were independent correlates of log urine pentosidine-to-creatinine ratio (R² = 0.190). When gender-adjusted log urine pentosidine-to-creatinine ratio stratified by smile frequency grade was compared using analysis of covariance, urine pentosidine-to-creatinine ratio was significantly decreased according to the increase in smile frequency. Our present findings suggest that measurement of urine pentosidine-to-creatinine ratio by a newly developed ELISA kit may be useful for identifying high-risk patients for fall-related fractures.

Fructose Consumption and Hepatocellular Carcinoma Promotion

Hepatocellular carcinoma (HCC) accounts for 85% of primary liver cancer, the third most common cause of cancer-related deaths worldwide. Its incidence has been increasing in both men and women. In Western countries, high-calorie diets, mainly rich in carbohydrates such as fructose, represent a significant concern due to their repercussions on the population’s health. A high-fructose diet is related to the development of Metabolic-Associated Fatty Liver Disease (MAFLD), formerly named Non-Alcoholic Fatty Liver Disease (NAFLD), and the progression of HCC as it potentiates the lipogenic pathway and the accumulation of lipids. However, fructose metabolism seems to be different between the stages of the disease, carrying out a metabolic reprogramming to favor the proliferation, inflammation, and metastatic properties of cancer cells in HCC. This review focuses on a better understanding of fructose metabolism in both scenarios: MAFLD and HCC.

Comparison of metabolic fate, target organs, and microbiota interactions of free and bound dietary advanced glycation end products

Increased intake of Western diets and ultra-processed foods is accompanied by increased intake of advanced glycation end products (AGEs). AGEs can be generated exogenously in the thermal processing of food and endogenously in the human body, which associated with various chronic diseases. In food, AGEs can be divided into free and bound forms, which differ in their bioavailability, digestion, absorption, gut microbial interactions and untargeted metabolites. We summarized the measurements and contents of free and bound AGE in foods. Moreover, the ingestion, digestion, absorption, excretion, gut microbiota interactions, and metabolites and metabolic pathways between free and bound AGEs based on animal and human studies were compared. Bound AGEs were predominant in most of the selected foods, while beer and soy sauce were rich in free AGEs. Only 10%-30% of AGEs were absorbed into the systemic circulation when orally administered. The excretion of ingested free and bound AGEs was approximately 90% and 60%, respectively. Dietary free CML has a detrimental effect on gut microbiota composition, while bound AGEs have both detrimental and beneficial impacts. Free and bound dietary AGEs changed amino acid metabolism, energy metabolism and carbohydrate metabolism. And besides, bound dietary AGEs altered vitamin metabolism, and glycerolipid metabolism.

Collagen crosslinking: effect on structure, mechanics and fibrosis progression

Biophysical properties of extracellular matrix (ECM), such as matrix stiffness, viscoelasticity and matrix fibrous structure, are emerging as important factors that regulate progression of fibrosis and other chronic diseases. The biophysical properties of the ECM can be rapidly and profoundly regulated by crosslinking reactions in enzymatic or non-enzymatic manners, which further alter the cellular responses and drive disease progression. In-depth understandings of crosslinking reactions will be helpful to reveal the underlying mechanisms of fibrosis progression and put forward new therapeutic targets, whereas related reviews are still devoid. Here, we focus on the main crosslinking mechanisms that commonly exist in a plethora of chronic diseases (e.g. fibrosis, cancer, osteoarthritis) and summarize current understandings including the biochemical reaction, the effect on ECM properties, the influence on cellular behaviors, and related studies in disease model establishment. Potential pharmaceutical interventions targeting the crosslinking process and relevant clinical studies are also introduced. Limitations of pharmaceutical development may be due to the lack of systemic investigations related to the influence on crosslinking mechanism from micro to macro level, which are discussed in the last section. We also propose the unclarified questions regarding crosslinking mechanisms and potential challenges in crosslinking-targeted therapeutics development.

Advanced glycation end product intake during pregnancy and offspring allergy outcomes: A Prospective cohort study

BACKGROUND

Associations have been shown between concurrent assessment of dietary intake of advanced glycation end products (AGEs) and childhood allergic outcomes. We examined the association between maternal AGEs intake and development of offspring asthma, wheeze, atopic dermatitis, allergic rhinitis and food allergies, and sought to determine whether the intake of AGEs was associated with cord sera cytokines/chemokines.

METHODS

Pregnant women ≥16 years were recruited in the Healthy Start study, a prospective pre-birth cohort from Colorado (N = 1410). The analysis included 962 dyads with adequate diet (≥2 recalls) and allergy outcome details. AGEs intake was estimated for each mother by matching intakes reported using 24-h dietary recalls during pregnancy to a reference database of commonly consumed foods' AGEs values. Child diagnoses of asthma and allergies up to 8 years were obtained from electronic medical records. Cord sera cytokines and chemokines were analysed in a subset (N = 462) of children.

RESULTS

The median [IQR] AGEs intake for the overall sample was 11,919 kU/day [8293, 16,573]. Unadjusted analysis showed a positive association between maternal AGEs intake in pregnancy and rhinitis up to 8 years of age (HR = 1.03; 95% CI: 1.01, 1.06), but the association was attenuated and no longer significant in adjusted models (HR = 1.01; 95% CI: 0.98, 1.04). Both adjusted and unadjusted models showed no associations between AGEs intake in pregnancy and any of the other outcomes (p > .05). There were no significant associations between any cytokine or chemokine measured and AGEs intake or any of the outcomes studied (p > .05).

CONCLUSION

The study showed that maternal AGEs intake was not associated with offspring asthma and allergy outcomes. AGEs exposure during pregnancy may not have the same impact on child development as postnatal exposure.

Human Pluripotent Stem Cell-Derived Hepatocyte-Like Cells and Organoids for Liver Disease and Therapy

Liver disease is a global health issue that has caused an economic burden worldwide. Organ transplantation is the only effective therapy for end-stage liver disease; however, it has been hampered by a shortage of donors. Human pluripotent stem cells (hPSCs) have been widely used for studying liver biology and pathology as well as facilitating the development of alternative therapies. hPSCs can differentiate into multiple types of cells, which enables the generation of various models that can be applied to investigate and recapitulate a range of biological activities in vitro. Here, we summarize the recent development of hPSC-derived hepatocytes and their applications in disease modeling, cell therapy, and drug discovery. We also discuss the advantages and limitations of these applications and critical challenges for further development.

Aging Induces Hepatic Oxidative Stress and Nuclear Proteomic Remodeling in Liver from Wistar Rats

Aging is a continuous, universal, and irreversible process that determines progressive loss of adaptability. The liver is a critical organ that supports digestion, metabolism, immunity, detoxification, vitamin storage, and hormone signaling. Nevertheless, the relationship between aging and the development of liver diseases remains elusive. In fact, although prolonged fasting in adult rodents and humans delays the onset of the disease and increases longevity, whether prolonged fasting could exert adverse effects in old organisms remains incompletely understood. In this work, we aimed to characterize the oxidative stress and nuclear proteome in the liver of 3-month- and 24-month-old male Wistar rats upon 36 h of fasting and its adaptation in response to 30 min of refeeding. To this end, we analyzed the hepatic lipid peroxidation levels (TBARS) and the expression levels of genes associated with fat metabolism and oxidative stress during aging. In addition, to gain a better insight into the molecular and cellular processes that characterize the liver of old rats, the hepatic nuclear proteome was also evaluated by isobaric tag quantitation (iTRAQ) mass spectrometry-based proteomics. In old rats, aging combined with prolonged fasting had great impact on lipid peroxidation in the liver that was associated with a marked downregulation of antioxidant genes (Sod2, Fmo3, and Cyp2C11) compared to young rats. Besides, our proteomic study revealed that RNA splicing is the hepatic nuclear biological process markedly affected by aging and this modification persists upon refeeding. Our results suggest that aged-induced changes in the nuclear proteome could affect processes associated with the adaptative response to refeeding after prolonged fasting, such as those involved in the defense against oxidative stress.

Advanced Glycation End-Products in Common Non-Infectious Liver Diseases: Systematic Review and Meta-Analysis

BACKGROUND

Excessive intake of fructose, glucose and alcohol is associated with the development of non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD). At the same time, these dietetic factors create an environment favorable for the generation of advanced glycation end-products. For this reason, advanced glycation end-products (AGEs) are hypothesized to play role in the development of NAFLD and ALD. In this systematic review and meta-analysis, we explore the relationship between NAFLD and ALD with AGE levels, including their diagnostic accuracy.

METHODS

The systematic review and meta-analysis has been pre-registered with PROSPERO (CRD42021240954) and was performed in accordance with the PRISMA guidelines. Meta-analyses were performed using the meta R package.

RESULTS

We have obtained 11 studies meeting our inclusion criteria, reporting data on 1844 participants (909 with NAFLD, 169 with ALD and 766 healthy controls). NAFLD was associated with significantly higher AGE fluorescence and serum N-(carboxyethyl)lysine (CEL) levels. Patients with alcoholic cirrhosis had significantly higher levels of N-(carboxymethyl)lysine (CML). Only individual studies examined AGEs in the context of their diagnostic accuracy. AGE fluorescence distinguished low and moderate steatosis with an AUC of 0.76. The ratio of CML, CEL and pentosidine to a soluble variant of the AGE receptor differentiated patients with NAFLD from healthy controls with high AUC (0.83-0.85). Glyceraldehyde-derived AGE separated non-alcoholic fatty liver (NAFL) from non-alcoholic steatohepatitis (NASH) with acceptable performance (AUC 0.78).

CONCLUSIONS

In conclusion, NAFLD and ALD are associated with significantly higher levels of several AGEs. More research is needed to examine the diagnostic accuracy of AGEs, however individual studies show that AGEs perform well in distinguishing NAFL from NASH.