Lipid Disorders and Metabolic-Associated Fatty Liver Disease

Cytoskeleton regulates lipid droplet fusion and lipid storage by controlling lipid droplet movement

Lipid droplets (LDs) are highly dynamic organelles that maintain cellular lipid homeostasis through size and number control. In adipose tissue, CIDEC plays a crucial role in LD fusion and lipid homeostasis. However, the regulatory factors and mechanisms of LD fusion remain largely unknown. Here, we established a high-throughput LD phenotypic screen on a compound library consisting of 2010 small molecules, and identified 11 cytoskeleton inhibitors that negatively regulate LD size. Using specific inhibitors against each of the three types of cytoskeleton, our data showed that the disruption of microtubules and microfilaments but not intermediate filaments limits CIDEC-mediated LD fusion and growth by reducing LD movement and LD-LD contact. The collective effect of microtubule inhibitors results in a small LD phenotype which favors lipolysis upon activation of cAMP-PKA pathway in adipocytes. Our findings demonstrate that cytoskeleton is involved in the process of LD fusion and growth, indicating their role in lipid storage metabolism. One-Sentence Summary: Cytoskeleton regulates lipid droplet fusion and lipid storage.

Association of advanced lung cancer inflammation index with all-cause and cardiovascular mortality in metabolic dysfunction associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), is a growing global health concern due to its rising prevalence and association with hepatic and cardiovascular diseases. This study aimed to assess the prognostic value of the Advanced Lung Cancer Inflammation Index (ALI)-a combined indicator of nutritional and inflammatory status-in predicting all-cause and cardiovascular mortality in MASLD patients.Data were drawn from MASLD-diagnosed adults (≥ 18 years) in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, with mortality tracked until December 31, 2019. ALI was calculated for each participant, and its relationship with long-term mortality was analyzed using multivariable Cox regression, restricted cubic spline (RCS) regression, and subgroup analyses. Additionally, the mediating role of biological age, including Klemera-Doubal method biological age (KDM BA) and homeostatic model assessment (HD), was assessed in this relationship through mediation analysis. Among 7,534 MASLD patients, higher ALI quintiles were significantly associated with reduced all-cause (aHR = 0.591, P = 0.004) and cardiovascular mortality (aHR = 0.393, P = 0.026). A nonlinear relationship was observed between ALI and mortality outcomes (P < 0.001). Subgroup analysis indicated ALI's stronger predictive value in older adults (≥ 60), females, and lifelong non-smokers. Mediation analysis showed that KDM BA and HD partially mediated the ALI-mortality relationship (34.02% and 37.87% for all-cause mortality; 37.60% and 58.69% for cardiovascular mortality, respectively). Higher values of the ALI are associated with reduced all-cause and cardiovascular mortality in patients with MASLD, with biological age serving as a partial mediator. Improved nutritional and inflammatory status enhances the prognosis of MASLD patients.

Effect of midlife exercise on lipid metabolism in aging mice: comparable to lifelong exercise, better than ceasing midlife exercise

This study examines the effects of continuous versus interrupted lifelong exercise on lipid metabolism in naturally aging male BALB/c mice. Five-week-old male BALB/c mice were randomly assigned to five groups: young control group (YC), natural ageing control group (AC), exercise cessation group (DE), middle-aged commencing exercise group (ME), and lifelong exercise group (LE). Moderate Intensity Continuous Training exercise sessions were conducted three times per week, with each session lasting 50 min; after exercise interventions until 72 weeks of age, the following parameters were measured: body morphology, exercise capacity, blood lipid, liver fat content, liver function, expression of liver lipid metabolism-related genes and endoplasmic reticulum stress-related genes, and activities of liver metabolism enzymes. The results suggest that advancing age leads to disrupted lipid processing, reduced hepatic performance, and increased endoplasmic reticular tension. Compared with the AC group, the ME and LE cohorts showed reduced serum lipids, whereas the LE group exhibited elevated high-density lipoprotein cholesterol (HDL-C) levels (P < 0.05). Post-exercise reductions were observed in hepatic total cholesterol and free fatty acid (FFA). Moreover, the exercises mitigated age-related hepatic impairments and diminished susceptibility towards cirrhosis despite higher aspartate aminotransferase (AST) and lower albumin (ALB) levels being evident within the DE cohort (P < 0.05). Exercise demonstrates the potential to mitigate age-related abnormalities in lipid metabolism. Middle-aged commencing and lifelong exercise interventions are more effective in alleviating lipid abnormalities than exercise cessation in middle age. This disparity in efficacy can be attributed to differences in regulating endoplasmic reticulum stress, enhancing liver lipid oxidation capacity, and reducing lipid synthesis ability. Notably, middle-aged individuals commencing exercise yield similar outcomes in regulating aging-associated abnormal lipid metabolism compared to the lifelong exercise group. This highlights the importance of initiating exercise in middle age, as it remains beneficial even if lifelong commitment is unfeasible, so exercise initiation in midlife is still beneficial. However, to prevent liver lipid metabolism disorders later in life, the earlier exercise initiation, the better.

The therapeutic potential of different mesenchymal stem cells and their derived exosomes in metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease is a metabolic disease with an increasing incidence. Its pathogenesis involves the interaction of multiple factors. There is currently no specific treatment, so early prevention and treatment are crucial. Mesenchymal stem cells are a type of cell with the ability to self-renew and differentiate in multiple directions. They have a wide range of sources, including umbilical cords, bone marrow, and fat, and have various biological functions such as anti-inflammation, immune regulation, anti-oxidation, and inhibition of fibrosis. They have shown significant potential in the treatment of non-alcoholic fatty liver disease. In recent years, mesenchymal stem cells derived exosomes have been shown to be rich in bioactive substances, and to be involved in intercellular communication, regulating metabolism, reducing inflammatory responses, improving lipid metabolism, inhibiting fibrosis, and other processes that contribute to the treatment of metabolic dysfunction-associated steatotic liver disease. Mesenchymal stem cells and mesenchymal stem cell-derived exosomes play an important role in the pathogenesis and treatment of metabolic dysfunction-associated steatotic liver disease and provide new potential and direction for the treatment of Metabolic dysfunction-associated steatotic liver disease. This article reviews the role and effects of mesenchymal stem cells and mesenchymal stem cell-derived exosomes from different sources in Metabolic dysfunction-associated steatotic liver disease and discusses their prospects as potential therapeutic strategies.

The Asian Pacific association for the study of the liver clinical practice guidelines for the diagnosis and management of metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD) affects over one-fourth of the global adult population and is the leading cause of liver disease worldwide. To address this, the Asian Pacific Association for the Study of the Liver (APASL) has created clinical practice guidelines focused on MAFLD. The guidelines cover various aspects of the disease, such as its epidemiology, diagnosis, screening, assessment, and treatment. The guidelines aim to advance clinical practice, knowledge, and research on MAFLD, particularly in special groups. The guidelines are designed to advance clinical practice, to provide evidence-based recommendations to assist healthcare stakeholders in decision-making and to improve patient care and disease awareness. The guidelines take into account the burden of clinical management for the healthcare sector.

GPR120 exacerbates the immune-inflammatory response in chicken liver by mediating acetochlor induced macrophage M1 polarization

Acetochlor is a widely used and highly effective herbicide. Its overuse poses significant threats to biosecurity and ecological integrity, particularly affecting free-ranging birds. Data on its impact, especially mechanisms of liver toxicity in chickens, are lacking. Thus, we established an animal-cell-animal model to explore intrinsic mechanisms at multiple levels. We found that acetochlor exposure caused liver cell swelling, inflammatory cell accumulation, and lipid deposition. Transcriptomic analyses revealed that differential gene were mainly enriched in hepatic immune, inflammatory, and programmed cell death pathways. We next focused on the gene GPR120, conducting transfection and agonism experiments in LMH, HD11, and co-cultured cells. Acetochlor significantly increased ROS accumulation, activated the NLRP3 inflammasome, and which induced PANoptosis. HD11 cells exhibited M1 polarization with upregulated pro-inflammatory factors. Silencing GPR120 exacerbated cellular damage and immune responses, whereas its agonist, GSK7A, dramatically reduced macrophage M1 polarization and mitigated immune damage to LMH cells. Finally, we returned to animal studies, adding Omega-3-a known GPR120 agonist-to the diet. Omega-3 effectively reversed acetochlor-induced hepatitis and PANoptosis. Given that acetochlor residues pose potential threats to ecosystems and avian health, it is crucial to strengthen residue control, conduct risk assessments, and explore targeted pathways and nutritional supplementation to counteract these negative impacts.

Chronic fat consumption affects metabolic aspects of murine physiology and influences ovarian follicle atresia

Saturated fat has been linked to cardiovascular diseases, leading to an increase in polyunsaturated fat consumption. The aim of the present study was to investigate the effects of three fat sources (coconut oil, lard and soybean oil) on metabolic and reproductive parameters in heterogenic mice. Female Swiss mice (5-6 weeks old; n = 9/group) were divided into four experimental groups: control (CC), coconut oil (CO), lard (LA), and soybean oil (SO), and were orally given 0.6 mL of the corresponding fat daily for 6 weeks to further investigate morphological, biochemical, and molecular parameters. SO females showed the highest glucose intolerance (P < 0.05), and all experimental groups were highly insulin resistant, with no statistical differences among them (P > 0.05). Moreover, all fat supplemented groups presented increased proportion in bile ducts, and CO and SO females presented higher LDL-cholesterol levels compared to CC (P < 0.05). Regarding reproductive parameters, estrous cycle alterations were observed mainly in the SO group, showing extended luteal phase duration (longer diestrus), and higher numbers of atretic follicles per area compared to the CC females (P < 0.05). Furthermore, higher proportion of active Casp-3 positive cells in the granulosa layers of preantral follicles were observed in the LA compared to the CO group (P < 0.05). The gene expression data revealed downregulation of Igf1r and Acvr1 in SO, upregulation of Igf1r in LA and Lhcgr in CO compared to CC females (P < 0.05). Thus, excessive fat intake may have deleterious effects on metabolism and reproductive function, but lard may be the least harmful source.

TMEM106B deficiency leads to alterations in lipid metabolism and obesity in the TDP-43Q331K knock-in mouse model

The TMEM106B gene, encoding a lysosomal membrane protein, is closely linked with brain aging and neurodegeneration. TMEM106B has been identified as a risk factor for several neurodegenerative diseases characterized by aggregation of the RNA-binding protein TDP-43, including frontotemporal lobar degeneration (FTLD) and limbic-predominant age-related TDP-43 encephalopathy (LATE). To investigate the role of TMEM106B in TDP-43 proteinopathy, we ablated TMEM106B in the TDP-43Q331K knock-in mouse line, which expresses an ALS-linked TDP-43 mutation at endogenous levels. We found that TMEM106B deficiency leads to glial activation, Purkinje cell loss, and behavioral deficits in TDP-43Q331K mice without inducing typical TDP-43 pathology. Interestingly, ablation of TMEM106B results in significant body weight gain, increased fat deposition, and hepatic triglyceride (TG) accumulation in TDP-43Q331K mice. In addition, lipidomic and transcriptome analysis shows a profound alteration in lipid metabolism in the liver of TDP-43Q331KTmem106b-/- mice. Our studies reveal a novel function of TMEM106B and TDP-43 in lipid metabolism and provide new insights into their roles in neurodegeneration.

Dapansutrile Regulates Mitochondrial Oxidative Stress and Reduces Hepatic Lipid Accumulation in Diabetic Mice

(1) Background: Hepatic lipid accumulation is the initial factor in metabolic-associated fatty liver disease (MAFLD) in type 2 diabetics, leading to accelerated liver damage. The NOD-like receptor protein 3 (NLRP3) inflammasome plays a critical role in this process. Dapansutrile (DAPA) is a novel NLRP3 inflammasome inhibitor; however, its effect on ectopic lipid accumulation in the liver remains unclear. This study aimed to investigate the therapeutic effect of DAPA on hepatic lipid accumulation in a diabetic mouse model and its potential mechanisms. (2) Methods: The effects of DAPA on hepatic ectopic lipid deposition and liver function under metabolic stress were evaluated in vivo using db/db and high-fat diet (HFD) + streptozotocin (STZ) mouse models. Additionally, the role and mechanism of DAPA in cellular lipid deposition, mitochondrial oxidative stress, and inflammation were assessed in HepG2 cells treated with free fatty acids (FFA) and DAPA. (3) Results: Our findings indicated that DAPA treatment improved glucose and lipid metabolism in diabetic mice, particularly addressing liver heterotopic lipid deposition and insulin resistance. DAPA treatment also ameliorated lipid accumulation and mitochondrial-related functions and inflammation in HepG2 cells through the NLRP3-Caspase-1 signaling axis. (4) Conclusions: Targeting NLRP3 with DAPA may represent a novel therapeutic approach for diabetes-related fatty liver diseases.

The association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and hepatic steatosis and liver fibrosis among US adults based on NHANES

Recently, the non-high-density to high-density lipoprotein cholesterol ratio (NHHR) has gained growing attention as an indicator for predicting diseases associated with lipid metabolism. Hepatic steatosis and fibrosis are tightly associated lipid metabolism. Our study aims to analyze the correlations among NHHR, hepatic steatosis, and fibrosis. This study analysed data from 14,578 adults in the US National Health and Nutrition Examination Survey (2005-2018). The degree of hepatic steatosis was measured through the Fatty Liver Index (FLI), while liver fibrosis severity was evaluated with the Fibrosis-4 (FIB-4) index. Multivariate linear regression assessed the association between NHHR and the FLI and FIB-4 score. Smooth curve describing the relationship between NHHR and FLI or FIB-4. Additionally, a two-part linear regression model adopted in order to more accurately account for the nonlinear relationship, with threshold effects estimated through its two components. To confirm the robustness of the findings, interaction tests and subgroup analyses were conducted. The multivariate logistic regression analysis demonstrated a significantly positive correlation of lnNHHR with FLI across all three models. In Model 3, the association was (β = 11.14, 95%CI:10.38,11.90). Curve fitting indicated a nonlinear relationship. The positive correlation between lnNHHR and FLI persists across gender, BMI, and physical activity groups. Nevertheless, a notable negative correlation between lnNHHR and FIB-4 was observed in all three models. In Model 3, the relationship between lnNHHR and FIB-4 was as follows: (β = -0.20; 95% CI: -0.22, -0.17). Curve fitting revealed a V-shaped relationship, with threshold effect analysis identifying a breakpoint at 1.51. Above this threshold, the relationship was found to be statistically insignificant (p-value = 0.424). Receiver operating characteristic (ROC) curve analysis demonstrated that NHHR exhibited better predictive performance for MASLD compared to non-HDL-C, HDL-C, and LDL-C/HDL-C. The current study's findings suggest that elevated levels of NHHR correlate with a greater risk of hepatic steatosis among adults in the U.S. Our findings imply that NHHR may be a valuable tool in improving MASLD prevention strategies in the general population.

Association between atherogenic index of plasma and infertility: a cross-sectional study based on U.S. women

BACKGROUND

A wealth of evidence indicates that dyslipidemia is associated with endothelial dysfunction, oxidative stress, and inflammation, each of which can impair reproductive function and lead to infertility. The Atherogenic Index of Plasma (AIP) is an innovative lipid biomarker that combines the triglyceride to high-density lipoprotein cholesterol (HDL-C) ratio, providing a more in-depth evaluation of lipid metabolism. This biomarker synthesizes discrete lipid disruptions into a single value, surpassing isolated lipid indicators' diagnostic value. The primary goal of our study was to explore the link between AIP and the incidence of infertility.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) spanning 2013-2018 were subjected to cross-sectional examination. The AIP is determined through the logarithmic transformation (base 10) of the triglyceride-to-HDL-C ratio. To uncover the connection between AIP and infertility, a suite of analytical techniques was employed, encompassing weighted multiple logistic regression, stratified analyses, spline curve modeling, and determination of cutoff values.

RESULTS

Among the 1,191 participants, with a weighted mean age of 31.89 years, 12.09% were diagnosed as infertile. The multivariate-adjusted odds ratios for infertility occurrence across the AIP quartiles were 1.00 (reference), 1.96 (95% CI: 1.10-3.49), 2.62 (95% CI: 1.48-4.63), and 2.38 (95% CI: 1.31-4.32), respectively. Subgroup examinations suggest that the association between AIP and infertility remains robust and is not substantially altered by factors including age, marital status, economic status, tobacco use, alcohol intake, and body mass index. Curve fitting and threshold analyses have indicated a positive nonlinear relationship between AIP and infertility, as well as a relatively stable incidence of infertility within the AIP range from -0.21 to 0.22.

CONCLUSIONS

Incorporating an assessment of AIP into the clinical evaluation could potentially refine the accuracy of risk estimation for infertility patients.

Proximity Ligation Induced DNAzyme Motor Cooperating with Exponential Amplification Reaction for Accurate Low-Density Lipoprotein (LDL) Detection

Low-density lipoprotein (LDL) is intricately associated with numerous clinical conditions, including dyslipidemia and metabolic-associated fatty liver disease (MAFLD), and its serum concentration is crucial for diagnostic purposes. However, the sensitive and accurate analysis of "intact" LDL is a significant difficulty, as conventional approaches typically focus solely on the detection of cholesterol or surface proteins of LDL. We developed a proximity ligation-induced DNAzyme motor that facilitates an outstanding amplification reaction for the precise and sensitive detection of LDL through the simultaneous recognition of the target ApoB and cholesterol. This technique facilitates the direct and accurate quantification of the concentration of "intact" LDL particles, as opposed to assessing the cholesterol content or ApoB protein inside LDL. The elevated amplification efficiency of the exponential amplification reaction, in conjunction with the trans-cleavage activity of the Cas14a1/crRNA complex, facilitates sensitive LDL detection with a low limit of detection of 6.12 mg/dL. The unique properties of the proposed method offer significant advantages in selectivity, stability, and sensitivity, rendering it extremely appropriate for diagnostics in MAFLD.

Inter-organ metabolic interaction networks in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a multisystem metabolic disorder, marked by abnormal lipid accumulation and intricate inter-organ interactions, which contribute to systemic metabolic imbalances. NAFLD may progress through several stages, including simple steatosis (NAFL), non-alcoholic steatohepatitis (NASH), cirrhosis, and potentially liver cancer. This disease is closely associated with metabolic disorders driven by overnutrition, with key pathological processes including lipid dysregulation, impaired lipid autophagy, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and local inflammation. While hepatic lipid metabolism in NAFLD is well-documented, further research into inter-organ communication mechanisms is crucial for a deeper understanding of NAFLD progression. This review delves into intrahepatic networks and tissue-specific signaling mediators involved in NAFLD pathogenesis, emphasizing their impact on distal organs.

Elevated GGT to HDL ratio as a marker for the risk of NAFLD and liver fibrosis

This study investigated the association between NAFLD and liver fibrosis and the ratio of gamma-glutamyl transferase to high-density lipoprotein cholesterol (GGT/HDL-C). In this cross-sectional study, we included 4764 subjects who participated in the National Health and Nutrition Examination Survey (NHANES) during 2017-2018. Adjusted multivariate logistic regression analysis was utilized to evaluate the relationships between GGT/HDL-C levels and NAFLD, fatty liver degree, and liver fibrosis. The non-linear link between NAFLD and the GGT/HDL-C ratio was examined using generalized additive models. There was a non-linear association between GGT/HDL-C and the risk of NAFLD, and all regression models demonstrated a strong relationship between GGT/HDL-C levels and the risk of liver fibrosis, the degree of hepatic steatosis, and the prevalence of NAFLD. Subgroup analyses revealed a significant correlation between the risk of NAFLD and the GGT/HDL-C ratio among Mexican Americans and young people in the 20-40 age range. The receiver operating characteristic (ROC) study showed that GGT/HDL-C was a more accurate predictor of NAFLD than GGT or HDL-C alone. In the U.S. population, an increased risk of NAFLD, the severity of hepatic steatosis, and the risk of liver fibrosis are independently correlated with an elevated GGT/HDL-C ratio.

Comparison of Risk Factors Between Lean and Nonlean Metabolic Dysfunction-Associated Steatotic Liver Disease in Individuals With Type 2 Diabetes: A Multicenter Study

OBJECTIVE

A multicenter study in patients with type 2 diabetes mellitus (T2DM) was performed to assess the differences of liver steatosis and fibrosis between lean and nonlean individuals.

METHODS

Patients with T2DM from 16 centers were recruited and underwent transient elastography examination for diagnosis of liver steatosis and fibrosis. Clinical information, such as diabetes status, serum lipids profiles, and inflammatory markers, were collected. Potential risk factors of liver steatosis and fibrosis in lean (body mass index [BMI] < 23 kg/m2) and nonlean (BMI ≥ 23 kg/m2) groups were analyzed.

RESULTS

A total of 1762 patients were included. The prevalence of liver steatosis and fibrosis in the lean group was 44.7% and 23.4%, respectively. The prevalence of hypertension and cardiovascular disease was higher in lean patients when compared with nonlean group. Lean patients with liver steatosis or fibrosis were older, had longer diabetes duration, lower levels of homeostatic model assessment for insulin resistance and serum lipids. The BMI, visceral fat area, and triglyceride were among the most significant correlators of liver steatosis for both nonlean and lean patients. However, lipid profiles were different between the two groups. Besides, insulin resistance, BMI, and lipid levels were not observed to be associated with fibrosis in the lean group.

CONCLUSION

In lean patients with T2DM, liver steatosis and fibrosis were less associated with insulin resistance. Risk factors of liver steatosis were different between lean and nonlean patients, indicating the necessity of risk stratification and tailored management strategies.

Application and mechanism of Chinese herb medicine in the treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver condition closely associated with metabolic syndrome, with its incidence rate continuously rising globally. Recent studies have shown that the development of NAFLD is associated with insulin resistance, lipid metabolism disorder, oxidative stress and endoplasmic reticulum stress. Therapeutic strategies for NAFLD include lifestyle modifications, pharmacological treatments, and emerging biological therapies; however, there is currently no specific drug to treat NAFLD. However Chinese herb medicine (CHM) has shown potential in the treatment of NAFLD due to its unique therapeutic concepts and methods for centuries in China. This review aims to summarize the pathogenesis of NAFLD and some CHMs that have been shown to have therapeutic effects on NAFLD, thus enriching the scientific connotation of TCM theories and facilitating the exploration of TCM in the treatment of NAFLD.

Role of MMP-2 and MMP-9 in the Relationship between Inflammation, Fibrosis, and Apoptosis during Progression of Non-Alcoholic Fatty Liver Disease and Diagnostic Significance of Plasma Levels of Their Active Forms

MMP-2 and MMP-9 play an important role in pathogenesis of chronic liver diseases, participating in the processes of inflammation and fibrosis. Their role in progression of non-alcoholic fatty liver disease (NAFLD) is poorly understood. Analysis of MMP-2, -9 levels in the blood plasma of patients with different forms of NAFLD [liver steatosis (LS) and non-alcoholic steatohepatitis (NASH) of weak (-WA), moderate (MA), high (-HA) activity without pronounced fibrosis] was performed. Correlations between the levels of MMP-2, -9 and mRNA of the genes MMP2, MMP9, ADAM17, NLRP3, caspase 3 activity in peripheral blood leukocytes (PBL), TNFα, IL-6, sIL-6R, cytokeratin-18 fragments in plasma were assessed. In steatosis, the levels of MMP2 gene mRNA in PBL and MMP-2 in plasma are lower than in the control, and expression of the NLRP3 gene in PBL is increased relative to other groups. In the NASH-WA, the level of MMP-9 is higher than in the control, in LS, and in NASH-MA, which could be associated with activation of inflammation during transformation of LS into NASH. The plasma level of MMP-9 over 389.50 pg/ml has been shown to be diagnostically significant for identification of NASH-WA among the patients with steatosis (AUC ROC = 0.818, 95% CI = 0.689-0.948, p < 0.001). In NAFLD, the level of MMP-9 could be associated not only with inflammation, but also with apoptosis. ADAM17 probably plays a certain role in this regard. In the advanced NASH, hepatocyte apoptosis is increased, the level of caspase 3 activity in PBL is increased, the level of MMP-9 in the blood is reduced to the level of the control and LS. In the NASH-HA, the level of mRNA of the ADAM17 gene in PBL is increased compared to the control, NASH-WA, and NASH-MA. Thus, MMP-2 and MMP-9 are involved in pathogenesis of NAFLD already at the early stages and their level in blood could be associated with the presence and severity of inflammation in the liver parenchyma.

Metabolic-Associated Fatty Liver Disease: The Influence of Oxidative Stress, Inflammation, Mitochondrial Dysfunctions, and the Role of Polyphenols

Metabolic-Associated Fatty Liver Disease (MAFLD) is a clinical-pathological scenario that occurs due to the accumulation of triglycerides in hepatocytes which is considered a significant cause of liver conditions and contributes to an increased risk of death worldwide. Even though the possible causes of MAFLD can involve the interaction of genetics, hormones, and nutrition, lifestyle (diet and sedentary lifestyle) is the most influential factor in developing this condition. Polyphenols comprise many natural chemical compounds that can be helpful in managing metabolic diseases. Therefore, the aim of this review was to investigate the impact of oxidative stress, inflammation, mitochondrial dysfunction, and the role of polyphenols in managing MAFLD. Some polyphenols can reverse part of the liver damage related to inflammation, oxidative stress, or mitochondrial dysfunction, and among them are anthocyanin, baicalin, catechin, curcumin, chlorogenic acid, didymin, epigallocatechin-3-gallate, luteolin, mangiferin, puerarin, punicalagin, resveratrol, and silymarin. These compounds have actions in reducing plasma liver enzymes, body mass index, waist circumference, adipose visceral indices, lipids, glycated hemoglobin, insulin resistance, and the HOMA index. They also reduce nuclear factor-KB (NF-KB), interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α), blood pressure, liver fat content, steatosis index, and fibrosis. On the other hand, they can improve HDL-c, adiponectin levels, and fibrogenesis markers. These results show that polyphenols are promising in the prevention and treatment of MAFLD.

Role of RIPK3 in lipid metabolism and postnatal overfeeding-induced metabolic disorders in mice

Postnatal overfeeding can increase the long-term risk of metabolic disorders, such as obesity, but the underlying mechanisms remain unclear and treatment approaches are limited. Receptor-interacting protein kinase 3 (RIPK3) is associated with several metabolic diseases. We investigated the effects of RIPK3 on neonatal overfeeding-related metabolic disorders. On postnatal day 3, litter sizes were adjusted to 9-10 (normal litters, NL) or 2-3 (small litters, SL) mice per dam to mimic postnatal overfeeding. After weaning, NL and SL mouse were fed normal diet. We generated an adeno-associated virus (AAV) carrying short hairpin RNA (shRNA) against Ripk3 and an empty vector as a control. The NL and SL groups were treated intravenously with 1×1012 vector genome of AAV vectors at week 6. The SL group showed a higher body weight than the NL group from week 3 of age through adulthood. At weeks 6 and 13, the SL group exhibited impaired glucose and insulin tolerance, RIPK3 up-regulation, and lipid accumulation in liver and adipose tissues. In the SL group, the genes involved in lipid synthesis and lipolysis were increased, whereas fatty acid β-oxidation-related genes were weakened in adipose tissue and liver. At week 13, AAV-shRNA-Ripk3 ameliorated adipose tissue hypertrophy, hepatic steatosis, insulin resistance, and dysregulated lipid metabolism in the adipose tissue and liver of SL mice. These findings support a novel mechanism underlying the pathogenesis of postnatal overfeeding-related metabolic disorders and suggest potential therapeutic targets.

Navigating the Link Between Non-alcoholic Fatty Liver Disease/Non-alcoholic Steatohepatitis and Cardiometabolic Syndrome

The global prevalence of non-alcoholic fatty liver disease (NAFLD) is nearly 25% and is increasing rapidly. The spectrum of liver damage in NAFLD ranges from simple steatosis to non-alcoholic steatohepatitis, characterised by the presence of lobular inflammation and hepatocyte ballooning degeneration, with or without fibrosis, which can further develop into cirrhosis and hepatocellular carcinoma. Not only is NAFLD a progressive liver disease, but numerous pieces of evidence also point to extrahepatic consequences. Accumulating evidence suggests that patients with NAFLD are also at increased risk of cardiovascular disease (CVD); in fact, CVDs are the most common cause of mortality in patients with NAFLD. Obesity, type 2 diabetes and higher levels of LDL are common risk factors in both NAFLD and CVD; however, how NAFLD affects the development and progression of CVD remains elusive. In this review, we comprehensively summarise current data on the key extrahepatic manifestations of NAFLD, emphasising the possible link between NAFLD and CVD, including the role of proprotein convertase substilisin/kenin type 9, extracellular vesicles, microbiota, and genetic factors.

Metabolic Dysfunction-associated Fatty Liver Disease: An Urgent Call for Global Action

There has been an exponential increase in the global prevalence of fatty liver disease in recent years in association with the obesity pandemic worldwide. 'Metabolic dysfunction-associated fatty liver disease', the new terminology adopted by an international panel of experts in 2020 to largely replace the old term 'non-alcoholic fatty liver disease', has now been accepted by most hepatologists and diabetologists across the globe. The term metabolic dysfunction-associated fatty liver disease was created to better reflect the metabolicand liver-specific manifestations and complications of fatty liver disease. It is important to disseminate our current understanding of this enigmatic disease among the global scientific fraternity. Recent publications, including articles from the latest issue of Endocrinology & Metabolism Clinics of North America, are attempting to fill this knowledge gap.

Accurate and sensitive low-density lipoprotein (LDL) detection based on the proximity ligation assisted rolling circle amplification (RCA)

Metabolic-associated fatty liver disease (MAFLD) is one of the leading causes of mortality from chronic diseases worldwide, and it is strongly linked to dyslipidemia. Dyslipidemia typically presents as an elevated concentration of low density lipoprotein (LDL). Hence, accurate quantification of LDL particles is crucial for predicting the risks of cardiovascular illnesses. Nevertheless, conventional techniques can merely provide indirect measurements of LDL particle concentrations through the detection of cholesterol or proteins within LDL particles, and they often require significant effort and time. Therefore, an accurate and effective method for identifying intact LDL particles is highly desired. We have devised a method that allows for the measurement of LDL concentration without the need for isolation. This method relies on proximity ligation rolling circle amplification (RCA). This technique enables the direct and precise measurement of the concentration of "actual" LDL particles, rather than measuring the cholesterol content inside LDL. It has a detection limit of 7.3 μg dL-1, which also meets the requirements for analyzing lipoproteins in clinical samples. Hence, this platform exhibits immense potential in clinical applications and health management.

Paxillin family proteins Hic-5 and LPXN promote lipid storage by regulating the ubiquitination degradation of CIDEC

Many metabolic diseases are caused by disorders of lipid homeostasis. CIDEC, a lipid droplet (LD)-associated protein, plays a critical role in controlling LD fusion and lipid storage. However, regulators of CIDEC remain largely unknown. Here, we established a homogeneous time-resolved fluorescence (HTRF)-based high-throughput screening method and identified LPXN as a positive regulatory candidate for CIDEC. LPXN and Hic-5, the members of the Paxillin family, are focal adhesion adaptor proteins that contribute to the recruitment of specific kinases and phosphatases, cofactors, and structural proteins, participating in the transduction of extracellular signals into intracellular responses. Our data showed that Hic-5 and LPXN significantly increased the protein level of CIDEC and enhanced CIDEC stability not through triacylglycerol synthesis and FAK signaling pathways. Hic-5 and LPXN reduced the ubiquitination of CIDEC and inhibited its proteasome degradation pathway. Furthermore, Hic-5 and LPXN enlarged LDs and promoted lipid storage in adipocytes. Therefore, we identified Hic-5 and LPXN as novel regulators of CIDEC. Our current findings also suggest intervention with Hic-5 and LPXN might ameliorate ectopic fat storage by enhancing the lipid storage capacity of white adipose tissues.