Development and validation of an image biomarker to identify metabolic dysfunction associated steatohepatitis: MR-MASH score

Targeting AMPK as a potential treatment for hepatic fibrosis in MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease, and often progresses to hepatic fibrosis, cirrhosis, and liver failure. Despite its increasing prevalence, effective pharmacological treatments for MASLD-related fibrosis remain limited. Recent research has highlighted AMP-activated protein kinase (AMPK) as a key regulator of the processes that promote fibrogenesis, and AMPK activation shows potential in mitigating fibrosis. Advances in AMPK activators and deeper insights into their role in fibrotic pathways have recently revitalized interest in targeting AMPK for fibrosis treatment. This review discusses the molecular mechanisms linking AMPK to hepatic fibrosis and evaluates emerging AMPK-directed therapies. Furthermore, it addresses challenges in clinical translation. Importantly, we combine the latest mechanistic discoveries with recent therapeutic developments to provide a comprehensive perspective on AMPK as a target for hepatic fibrosis treatment.

Accuracy of Non-Invasive Imaging Techniques for the Diagnosis of MASH in Patients With MASLD: A Systematic Review

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing public health problem. The secondary stage in MASLD is steatohepatitis (MASH), the co-existence of steatosis and inflammation, a leading cause of progression to fibrosis and mortality. MASH resolution alone improves survival. Currently, MASH diagnosis is via liver biopsy. This study sought to evaluate the accuracy of imaging-based tests for MASH diagnosis, which offer a non-invasive method of diagnosis.

METHODS

Eight academic literature databases were searched and references of previous systematic reviews and included papers were checked for additional papers. Liver biopsy was used for reference standard.

RESULTS

We report on 69 imaging-based studies. There were 31 studies on MRI, 27 on ultrasound, five on CT, 13 on transient elastography, eight on controlled attenuation parameter (CAP) and two on scintigraphy. The pathological definition of MASH was inconsistent, making it difficult to compare studies. 55/69 studies (79.71%) were deemed high-risk of bias as they had no preset thresholds and no validation. The two largest groups of imaging papers were on MRI and ultrasound. AUROCs were up to 0.93 for MRE, 0.90 for MRI, 1.0 for magnetic resonance spectroscopy (MRS) and 0.94 for ultrasound-based studies.

CONCLUSIONS

Our study found that the most promising imaging tools are MRI techniques or ultrasound-based scores and confirmed there is potential to utilise these for MASH diagnosis. However, many publications are single studies without independent prospective validation. Without this, there is no clear imaging tool or score currently available that is reliably tested to diagnose MASH.

The fibrosis-4 index and its association with carotid atherosclerosis in type 2 diabetes: a cross-sectional study in China

BACKGROUND

The medical community has long been concerned about the cardiovascular disease risk in patients with type 2 diabetes. While liver fibrosis scores were originally designed for application in individuals with liver steatosis, an increasing number of studies have shown that they are also associated with cardiovascular disease risk. However, the association between Fibrosis-4 (Fib-4) in liver fibrosis scores and carotid atherosclerosis (CA) in patients with type 2 diabetes remains unclear.

OBJECTIVE

The aim of this study is to investigate the association between the Fib-4 index and CA in patients with Type 2 diabetes. Additionally, it seeks to determine whether this relationship is influenced by factors including gender, age, body mass index (BMI), hypertension, and other variables.

METHODS

Screening based on inclusion and exclusion criteria identified 2658 hospitalized patients with type 2 diabetes. Subsequently, patients were divided into three groups according to Fib-4 values (Fib-4 < 1.3, 1.3 ≤ Fib-4 < 2.67, Fib-4 ≥ 2.67). Logistic regression analysis was then applied to evaluate the association between Fib-4 and the presence of CA in type 2 diabetes. Further stratified analyses were conducted considering gender, age (using 60 years as the threshold), hypertension status, smoking, alcohol consumption, and BMI groups (using 24 kg/m2 as the threshold), aiming to investigate potential effect heterogeneity within predefined subgroups. ROC curve analysis was used to evaluate the predictive power of the Fib-4 value for CA, increased CIMT, and carotid plaques.

RESULTS

The study encompassed 2658 patients diagnosed with type 2 diabetes, comprising 1441 males and 1217 females, with an average age of 56.71 ± 10.22 years. Among them, 1736 individuals (65.3%) exhibited CA, 1243 (46.8%) had increased carotid intima-media thickness (CIMT), and 1273 (47.9%) manifested carotid plaques. Following adjustments for various factors, the prevalence of CA exhibited a progressive increase in the Fib-4 < 1.3, 1.3 ≤ Fib-4 < 2.67, and Fib-4 ≥ 2.67 groups, with statistically significant differences (P < 0.05). Moreover, the prevalence of increased CIMT and carotid plaques in the Fib-4 ≥ 2.67 group remained significantly higher than that in the Fib-4 < 1.3 group after considering various factors (P < 0.05). In the 1.3 ≤ Fib-4 < 2.67 group, subsequent to adjustments for gender, smoking, and drinking, the prevalence of increased CIMT and carotid plaques surpassed that in the Fib-4 < 1.3 group (P < 0.05). Despite further adjustments for multiple factors, the prevalence of increased CIMT and carotid plaques persisted higher than that in the Fib-4 < 1.3 group, yet the difference lacked statistical significance (P > 0.05). The results of the ROC curve analysis indicated that the AUC for Fib-4 predicting CA was 0.602 (P < 0.001, 95% CI: 0.579-0.625), while the AUC values for increased CIMT and carotid plaques were 0.561 (P < 0.001, 95% CI: 0.540-0.583) and 0.580 (P < 0.001, 95% CI: 0.558-0.601), respectively.

CONCLUSION

Elevated Fib-4 levels (Fib-4 ≥ 1.3) are positively associated with CA in patients with type 2 diabetes, including increased CIMT and the presence of carotid plaques. As such, Fib-4 may serve as a potential biomarker for the detection of CA in patients with type 2 diabetes. However, its clinical utility needs further validation, particularly in larger sample sizes and multicenter studies.

New Insights into AMPK, as a Potential Therapeutic Target in Metabolic Dysfunction-Associated Steatotic Liver Disease and Hepatic Fibrosis

AMP-activated protein kinase (AMPK) activators have garnered significant attention for their potential to prevent the progression of metabolic dysfunction-associated steatotic liver disease (MASLD) into liver fibrosis and to fundamentally improve liver function. The broad spectrum of pathways regulated by AMPK activators makes them promising alternatives to conventional liver replacement therapies and the limited pharmacological treatments currently available. In this study, we aim to illustrate the newly detailed multiple mechanisms of MASLD progression based on the multiple-hit hypothesis. This model posits that impaired lipid metabolism, combined with insulin resistance and metabolic imbalance, initiates inflammatory cascades, gut dysbiosis, and the accumulation of toxic metabolites, ultimately promoting fibrosis and accelerating MASLD progression to irreversible hepatocellular carcinoma (HCC). AMPK plays a multifaceted protective role against these pathological conditions by regulating several key downstream signaling pathways. It regulates biological effectors critical to metabolic and inflammatory responses, such as SIRT1, Nrf2, mTOR, and TGF-β, through complex and interrelated mechanisms. Due to these intricate connections, AMPK's role is pivotal in managing metabolic and inflammatory disorders. In this review, we demonstrate the specific roles of AMPK and its related pathways. Several agents directly activate AMPK by binding as agonists, while some others indirectly activate AMPK by modulating upstream molecules, including adiponectin, LKB1, and the AMP: ATP ratio. As AMPK activators can target each stage of MASLD progression, the development of AMPK activators offers immense potential to expand therapeutic strategies for liver diseases such as MASH, MASLD, and liver fibrosis.