Oral Administration of CardioAid and Lunasin Alleviates Liver Damage in a High-Fat Diet Nonalcoholic Steatohepatitis Model

A promising therapy for fatty liver disease: PCSK9 inhibitors

BACKGROUND

Fatty liver disease (FLD) poses a significant global health concern worldwide, with its classification into nonalcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD) contingent upon the presence or absence of chronic and excessive alcohol consumption. The absence of specific therapeutic interventions tailored to FLD at various stages of the disease renders its treatment exceptionally arduous. Despite the fact that FLD and hyperlipidemia are intimately associated, there is still debate over how lipid-lowering medications affect FLD. Proprotein Convertase Subtilisin/ Kexin type 9 (PCSK9) is a serine protease predominantly synthesized in the liver, which has a crucial impact on cholesterol homeostasis. Research has confirmed that PCSK9 inhibitors have prominent lipid-lowering properties and substantial clinical effectiveness, thereby justifying the need for additional exploration of their potential role in FLD.

PURPOSE

Through a comprehensive literature search, this review is to identify the relationship and related mechanisms between PCSK9, lipid metabolism and FLD. Additionally, it will assess the pharmacological mechanism and applicability of PCSK9 inhibitors (including naturally occurring PCSK9 inhibitors, such as conventional herbal medicines) for the treatment of FLD and serve as a guide for updating the treatment protocol for such conditions.

METHODS

A comprehensive literature search was conducted using several electronic databases, including Pubmed, Medline, Embase, CNKI, Wanfang database and ClinicalTrials.gov, from the inception of the database to 30 Jan 2024. Key words used in the literature search were "fatty liver", "hepatic steatosis", "PCSK9", "traditional Chinese medicine", "herb medicine", "botanical medicine", "clinical trial", "vivo", "vitro", linked with AND/OR. Most of the included studies were within five years.

RESULTS

PCSK9 participates in the regulation of circulating lipids via both LDLR dependent and independent pathways, and there is a potential association with de novo lipogenesis. Major clinical studies have demonstrated a positive correlation between circulating PCSK9 levels and the severity of NAFLD, with elevated levels of circulating PCSK9 observed in individuals exposed to chronic alcohol. Numerous studies have demonstrated the potential of PCSK9 inhibitors to ameliorate non-alcoholic steatohepatitis (NASH), potentially completely alleviate liver steatosis, and diminish liver impairment. In animal experiments, PCSK9 inhibitors have exhibited efficacy in alleviating alcoholic induced liver lipid accumulation and hepatitis. Traditional Chinese medicine such as berberine, curcumin, resveratrol, piceatannol, sauchinone, lupin, quercetin, salidroside, ginkgolide, tanshinone, lunasin, Capsella bursa-pastoris, gypenosides, and Morus alba leaves are the main natural PCS9 inhibitors. Excitingly, by inhibiting transcription, reducing secretion, direct targeting and other pathways, traditional Chinese medicine exert inhibitory effects on PCSK9, thereby exerting potential FLD therapeutic effects.

CONCLUSION

PCSK9 plays an important role in the development of FLD, and PCSK9 inhibitors have demonstrated beneficial effects on lipid regulation and FLD in both preclinical and clinical studies. In addition, some traditional Chinese medicines have improved the disease progression of FLD by inhibiting PCSK9 and anti-inflammatory and antioxidant effects. Consequently, the inhibition of PCSK9 appears to be a promising therapeutic strategy for FLD.

Sterols in Inflammatory Diseases: Implications and Clinical Utility

The characteristic steroid skeleton, with its 4-ringed 17-carbon structure, is one of the most recognizable organic compounds in biochemistry. In the presence of a hydroxyl ion bound to the third carbon, this structure is defined as a "sterol" (chemical formula: C17H28O). The hydroxyl group provides a hydrophilic site for the otherwise hydrophobic molecule, yielding an amphipathic lipid, which is a vital property for cellular function. It is crucial to remark that the term "steroid" describes a larger group of compounds that often retain the hydroxyl group but are primarily characterized by methyl groups, double bonds in the rings, and an aliphatic side-chain extending from the 17th carbon. In addition to serving various structural roles in the cellular membrane, sterols and steroids contribute to cellular and systemic functions as messengers, hormones, and regulators of several critical metabolic pathways.Sterol nomenclature is often confusing, partly due to structural complexity and partly due to the sheer number of different compounds that fall under the definition. Fortunately, the foremost sterols of interest in biochemistry are much fewer, and therefore, these lipids have been defined and studied vigorously. With the renaissance of lipid research during the 1990s and 2000s, many different metabolites of sterols, and more specifically phytosterols, were found to be associated with various diseases and conditions, including cardiovascular disease, hypercholesterolemia, cancer, obesity, inflammation, diabetes, and inborn errors of metabolism; thus, it is evident that the ever-evolving research in this field has been, and will continue to be, exceedingly productive.With respect to inflammation and inflammatory diseases, plant-based sterols (i.e., phytosterols) have gained considerable fame due to their anti-inflammatory and cholesterol-lowering effects demonstrated by experimental and clinical research. Besides, the exceptional pharmacological benefits of these sterols, which operate as antioxidant, antidiabetic, and anti-atherosclerotic agents, have been the subject of various investigations. While the underlying mechanisms necessitate further research, the possible function of phytosterols in improving health outcomes is an important topic to explore.In this regard, the current review aims to offer comprehensive information on the therapeutic potential of plant-based sterols in the context of human health, with a focus on preclinical effects, bioavailability, and clinical use.

Lunasin ameliorates glucose utilization in C2C12 myotubes and metabolites profile in diet-induced obese mice benefiting metabolic disorders

AIMS

Obesity is the main cause of low-grade inflammation and oxidation, resulting in insulin resistance. This study aimed to investigate the effects of a seed peptide lunasin on glucose utilization in C2C12 myotubes and the metabolite profiles in obese mice.

MAIN METHODS

C2C12 myotubes were challenged by palmitic acid (PA) to mimic the obese microenvironment and inflammation, cell vitality, and glucose utilization were determined. C57BL6/j mice were divided into low-fat diet (LF), high-fat diet (HF), and HF with intraperitoneally injected lunasin (HFL) groups. Glucose intolerance and metabolite profiles of the tissues were analyzed.

KEY FINDINGS

In vitro, C2C12 myotubes treated with lunasin showed decreased proinflammatory cytokines and increased cell vitality under palmitic acid conditions. Lunasin improved glucose uptake and glucose transporter 4 expression by activating insulin receptor substrate-1 and AKT phosphorylation. Next-generation sequencing revealed that lunasin regulates genes expression by promoting insulin secretion and decreasing oxidative stress. In vivo, HF mice showed increased tricarboxylic acid cycle and uric acid metabolites but decreased bile acids metabolites and specific amino acids. Lunasin intervention improved glucose intolerance and modulated metabolites associated with increased insulin sensitivity and decreased metabolic disorders.

SIGNIFICANCE

This study is the first to reveal that lunasin is a promising regulator of anti-inflammation, anti-oxidation, and glucose utilization in myotubes and ameliorating glucose uptake and metabolite profiles in obese mice, contributing to glucose homeostasis and benefiting metabolic disorders.

Decoding the role of immune T cells: A new territory for improvement of metabolic-associated fatty liver disease

Metabolic-associated fatty liver disease (MAFLD) is a new emerging concept and is associated with metabolic dysfunction, generally replacing the name of nonalcoholic fatty liver disease (NAFLD) due to heterogeneous liver condition and inaccuracies in definition. The prevalence of MAFLD is rising by year due to dietary changes, metabolic disorders, and no approved therapy, affecting a quarter of the global population and representing a major economic problem that burdens healthcare systems. Currently, in addition to the common causative factors like insulin resistance, oxidative stress, and lipotoxicity, the role of immune cells, especially T cells, played in MAFLD is increasingly being emphasized by global scholars. Based on the diverse classification and pathophysiological effects of immune T cells, we comprehensively analyzed their bidirectional regulatory effects on the hepatic inflammatory microenvironment and MAFLD progression. This interaction between MAFLD and T cells was also associated with hepatic-intestinal immune crosstalk and gut microbiota homeostasis. Moreover, we pointed out several T-cell-based therapeutic approaches including but not limited to adoptive transfer of T cells, fecal microbiota transplantation, and drug therapy, especially for natural products and Chinese herbal prescriptions. Overall, this study contributes to a better understanding of the important role of T cells played in MAFLD progression and corresponding therapeutic options and provides a potential reference for further drug development.

Phytosterols as bioactive food components against nonalcoholic fatty liver disease

Phytosterols are bioactive food components widely present in cell membranes of plants, especially in nuts and oilseeds. In recent years, many studies have shown that phytosterols possess therapeutic potentials for nonalcoholic fatty liver disease (NAFLD). This review summarizes the effects of phytosterols from in vitro and in vivo studies to lower the levels of total cholesterol (TC) and triglycerides (TG), and the evidence supporting the potential of phytosterols against NAFLD. The potential mechanisms by which phytosterols improve NAFLD may include (i) competition with cholesterol; (ii) regulation of key factors involved in cholesterol and TG metabolism; and (iii) inhibition of liver inflammation and (iv) regulation of liver fatty acid composition. In summary, phytosterols are potential natural ingredients with good safety profile against NAFLD, which deserve more future studies.

Plant-based sterols and stanols in health & disease: "Consequences of human development in a plant-based environment?"

Dietary plant sterols and stanols as present in our diet and in functional foods are well-known for their inhibitory effects on intestinal cholesterol absorption, which translates into lower low-density lipoprotein cholesterol concentrations. However, emerging evidence suggests that plant sterols and stanols have numerous additional health effects, which are largely unnoticed in the current scientific literature. Therefore, in this review we pose the intriguing question "What would have occurred if plant sterols and stanols had been discovered and embraced by disciplines such as immunology, hepatology, pulmonology or gastroenterology before being positioned as cholesterol-lowering molecules?" What would then have been the main benefits and fields of application of plant sterols and stanols today? We here discuss potential effects ranging from its presence and function intrauterine and in breast milk towards a potential role in the development of non-alcoholic steatohepatitis (NASH), cardiovascular disease (CVD), inflammatory bowel diseases (IBD) and allergic asthma. Interestingly, effects clearly depend on the route of entrance as observed in intestinal-failure associated liver disease (IFALD) during parenteral nutrition regimens. It is only until recently that effects beyond lowering of cholesterol concentrations are being explored systematically. Thus, there is a clear need to understand the full health effects of plant sterols and stanols.

Current state of art after twenty years of the discovery of bioactive peptide lunasin

Non-communicable diseases have become the medical challenge of the 21st century because of their high incidence and mortality rates. Accumulating evidence has suggested that the modulation of diet and other lifestyle habits is the best strategy for the prevention of these diseases. An increasing number of dietary compounds have been found to exert health promoting benefits beyond their nutritional effects. Among them, lunasin is considered one of the most studied bioactive peptides. Since its discovery in soybean twenty years ago, many researchers around the world have focused their studies on demonstrating the chemopreventive and chemotherapeutic activity of lunasin. Moreover, in the last years, promising protective effects of this peptide against hypercholesterolemia, obesity, metabolic syndrome and associated cardiovascular disorders, and inflammatory and immune-regulated diseases have been described. This review summarizes recent remarkable advances on the use of peptide lunasin as a potential functional ingredient to provide health benefits. Moreover, novel aspects related to the influence of lunasin's digestion and bioavailability, the mechanisms of action proposed to explain the underlying biological properties, and the incorporation of this peptide into nutritional supplements are critically discussed.

Preventive effect of trans-chalcone on non-alcoholic steatohepatitis: Improvement of hepatic lipid metabolism

Non-alcoholic steatohepatitis (NASH) is an inflammatory and progressive form of non-alcoholic fatty liver disease. However, there are no FDA-approved drugs for this condition. Lipids accumulated in NASH have a direct role in the progression of this disease. Therefore, this study for the first time explored the preventive effect of trans-chalcone on NASH through the modulation of sterol regulatory element binding protein (SREBP)-1c, SREBP-2, hepatic fatty acid synthesis (FAS) enzyme, proliferator-activated receptor (PPAR)-α, and PPAR-γ2 levels, which are involved in hepatic lipid metabolism. In this study, male rats were randomly divided into three groups (n = 7): Control, received 10% tween 80; NASH, received 10% tween 80 and 10 ml/kg high-fat emulsion (high-fat diet, HFD); and NASH + TC, received 20 mg/kg trans-chalcone and 10 ml/kg HFD. All treatments were performed by once-daily oral gavage for 6 weeks. Liver and blood samples were collected and serum levels of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol, as well as hepatic levels of SREBP-1c, SREBP-2, FAS, PPAR-α, and PPAR-γ2, were measured. Moreover, hematoxylin and eosin stained tissues were used for histological analysis. In this study, treatment of HFD-fed rats with trans-chalcone significantly reduced abnormalities in liver histology, serum levels of liver injury markers, liver index, and hepatic levels of SREBP-1c, SREBP-2, FAS, and PPAR-γ2. Furthermore, trans-chalcone significantly increased hepatic PPARα levels in these rats. Therefore, it seems that trans-chalcone protects the liver of HFD-fed rats against NASH development through reduction of SREBP-1c/ FAS- and PPAR-γ2-related lipogenesis, attenuation of SREBP-2-related cholesterol synthesis, and elevation of PPARα-related fatty acid oxidation.

Updating the research on the chemopreventive and therapeutic role of the peptide lunasin

Chronic diseases have become the medical challenge of the 21st century because of their high incidence and mortality rates. Modulation of diet and lifestyle habits is considered as the best strategy for the prevention of these disorders. Health promoting benefits beyond their nutritional effects have been described for multiple dietary compounds. Among these compounds, the peptide lunasin is considered as one of the most promising. Naturally present in soybean, lunasin has been extensively studied in the last two decades because of its potential against chronic diseases such as cancer, cardiovascular and immunological disorders. The purpose of this article is to summarise the evidence on the presence of lunasin in soybean and derived foods, and its bioavailability once it is orally ingested. The protective and therapeutic effects of this peptide against cancer, oxidative stress, inflammation, and high cholesterol levels as well as the molecular mechanisms of action involved in these effects are also described in this review. © 2017 Society of Chemical Industry.