Hispaglabridin B, a constituent of liquorice identified by a bioinformatics and machine learning approach, relieves protein-energy wasting by inhibiting forkhead box O1

Lobetyolin Alleviates Ferroptosis of Skeletal Muscle in 5/6 Nephrectomized Mice via Activation of Hedgehog-GLI1 Signaling

BACKGROUND

Muscle wasting increases morbidity and mortality and is related to chronic kidney disease (CKD) and dialysis. It is still unclear whether ferroptosis occurs during this progression and whether it is a potential intervention target for the treatment of CKD-related muscle injury.

PURPOSE

The objective is to identify potential compounds for treating ferroptosis and muscle wasting and explore the potential mechanisms in vivo/in vitro.

METHODS

Initially, we explored whether ferroptosis is present in the skeletal muscle of 5/6 nephrectomized (NPM) mice via RNA-Seq analysis, TUNEL staining, Oil red O staining, MDA/GSH/GSSG level detection and real-time quantitative PCR (qPCR). Subsequently, utilizing our established molecular phenotyping strategy, we screened potential traditional Chinese herb-derived compounds for alleviation of muscle wasting and ferroptosis. HE staining, Oil red O staining, TUNEL staining, immunofluorescence staining, MDA/GSH/GSSG level detection, Fe level detection, western blotting and qPCR were applied to assess the effects of the identified compound on muscle wasting and ferroptosis and explore the potential mechanism. Furthermore, RNA-Seq analysis, ChIP-Seq analysis and further experiments in vitro were performed to determine the role of Hedgehog signaling in the effect of Lobetyolin (LBT) on ferroptosis.

RESULTS

In NPM mice, skeletal muscle dysfunction, lipogenesis, reduced GSH/GSSG ratio, decreased GSH content, increased MDA production and and higher levels of ferroptosis markers were observed. LBT treatment (30 mg/kg or 50 mg/kg) significantly alleviates skeletal muscle injury by inhibiting ferroptosis. Additionally, in an in vitro investigation, C2C12 cells exposed to Indolyl sulfate (IS) induced ferroptosis and LBT treatment (20 μM and 50 μM) protected C2C12 from such injury, consistent with the results from the in vivo analysis. Furthermore, it was found LBT increased the levels of protein involving Hedgehog signaling pathway (SMO and GLI1), and rescue analysis revealed that this pathway played a crucial role in the regulation of ferroptosis. Further experiments demonstrated that LBT upregulated a series of suppressors of ferroptosis by activating Gli1 transcription.

CONCLUSION

LBT alleviates CKD-induced muscle injury by inhibiting ferroptosis through activation of the Hedgehog signaling pathway.

A molecular phenotypic screen reveals that lobetyolin alleviates cardiac dysfunction in 5/6 nephrectomized mice by inhibiting osteopontin

BACKGROUND

Cardiovascular diseases are the major cause of mortality in patients with advanced chronic kidney diseases. The predominant abnormality observed among this population is cardiac dysfunction secondary to myocardial remodelings, such as hypertrophy and fibrosis, emphasizing the need to develop potent therapies that maintain cardiac function in patients with end-stage renal disease.

AIMS

To identify potential compounds and their targets as treatments for cardiorenal syndrome type 4 (CRS) using molecular phenotyping and in vivo/in vitro experiments.

METHODS

Gene expression was assessed using bioinformatics and verified in animal experiments using 5/6 nephrectomized mice (NPM). Based on this information, a molecular phenotyping strategy was pursued to screen potential compounds. Picrosirius red staining, wheat germ agglutinin staining, Echocardiography, immunofluorescence staining, and real-time quantitative PCR (qPCR) were utilized to evaluate the effects of compounds on CRS in vivo. Furthermore, qPCR, immunofluorescence staining and flow cytometry were applied to assess the effects of these compounds on macrophages/cardiac fibroblasts/cardiomyocytes. RNA-Seq analysis was performed to locate the targets of the selected compounds. Western blotting was performed to validate the targets and mechanisms. The reversibility of these effects was tested by overexpressing Osteopontin (OPN).

RESULTS

OPN expression increased more remarkably in individuals with uremia-induced cardiac dysfunction than in other cardiomyopathies. Lobetyolin (LBT) was identified in the compound screen, and it improved cardiac dysfunction and suppressed remodeling in NPM mice. Additionally, OPN modulated the effect of LBT on cardiac dysfunction in vivo and in vitro. Further experiments revealed that LBT suppressed OPN expression via the phosphorylation of c-Jun N-terminal protein kinase (JNK) signaling pathway.

CONCLUSIONS

LBT improved CRS by inhibiting OPN expression through the JNK pathway. This study is the first to describe a cardioprotective effect of LBT and provides new insights into CRS drug discovery.

Zhen-Wu decoction and lactiflorin, an ingredient predicted by in silico modelling, alleviate uremia induced cardiac endothelial injury via Nrf2 activation

ETHNOPHARMACOLOGICAL RELEVANCE

Cardiorenal syndrome type 4 (CRS type 4), with high rates of morbidity and mortality, has become a social and economic problem worldwide over the last few decades. Zhen-Wu decoction, a traditional medicine used in East Asia, has been widely used in the treatment of cardiovascular disease and kidney disease, and has shown potential therapeutic effects for the clinical treatment of CRS type 4. However, the underlying mechanism has not been extensively explored.

AIM OF THE STUDY

The purpose of this study was to investigate the effect and underlying mechanism of Zhen-Wu decoction on uremic cardiomyopathy, offering a potential target for clinical treatment of CRS type 4.

MATERIALS AND METHODS

Five/six nephrectomized mice were utilized for experiments in vivo. The cardioprotective effects of Zhen-Wu decoction were evaluated by echocardiography and tissue staining. RNA-Seq data were used to investigate the potential pharmacological mechanism. The prediction of targets and active components was based on our previous strategy. Subsequently, the protective effect of the selected compound was verified in experiments in vitro.

RESULTS

Zhen-Wu decoction alleviated cardiac dysfunction and endothelial injury in 5/6 nephrectomized mice, and the mechanism may involve the inflammatory process and oxidative stress. The activation of the Nrf2 signaling pathway was predicted to be a potential target of Zhen-Wu decoction in protecting endothelial cells. Through our machine learning strategy, we found that lactiflorin as an ingredient in Zhen-Wu decoction, alleviates IS-induced endothelial cell injury by blocking Keap1 and activating Nrf2.

CONCLUSIONS

The present study demonstrated that Zhen-Wu decoction and lactiflorin could protect endothelial cells against oxidative stress in mice after nephrectomy by activating the Nrf2 signaling pathway.

Paeoniflorin Ameliorates Skeletal Muscle Atrophy in Chronic Kidney Disease via AMPK/SIRT1/PGC-1α-Mediated Oxidative Stress and Mitochondrial Dysfunction

Skeletal muscle atrophy is a common and serious complication of chronic kidney disease (CKD). Oxidative stress and mitochondrial dysfunction are involved in the pathogenesis of muscle atrophy. The aim of this study was to explore the effects and mechanisms of paeoniflorin on CKD skeletal muscle atrophy. We demonstrated that paeoniflorin significantly improved renal function, calcium/phosphorus disorders, nutrition index and skeletal muscle atrophy in the 5/6 nephrectomized model rats. Paeoniflorin ameliorated the expression of proteins associated with muscle atrophy and muscle differentiation, including muscle atrophy F-box (MAFbx/atrogin-1), muscle RING finger 1 (MuRF1), MyoD and myogenin (MyoG). In addition, paeoniflorin modulated redox homeostasis by increasing antioxidant activity and suppressing excessive accumulation of reactive oxygen species (ROS). Paeoniflorin alleviated mitochondrial dysfunction by increasing the activities of electron transport chain complexes and mitochondrial membrane potential. Furthermore, paeoniflorin also regulates mitochondrial dynamics. Importantly, paeoniflorin upregulated the expression of silent information regulator 1 (SIRT1), peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), and phosphorylation of AMP-activated protein kinase (AMPK). Similar results were observed in C2C12 myoblasts treated with TNF-α and paeoniflorin. Notably, these beneficial effects of paeoniflorin on muscle atrophy were abolished by inhibiting AMPK and SIRT1 and knocking down PGC-1α. Taken together, this study showed for the first time that paeoniflorin has great therapeutic potential for CKD skeletal muscle atrophy through AMPK/SIRT1/PGC-1α-mediated oxidative stress and mitochondrial dysfunction.

Glycyrrhiza glabra (Licorice): A Comprehensive Review on Its Phytochemistry, Biological Activities, Clinical Evidence and Toxicology

There are more than 30 species of Glycyrrhiza genus extensively spread worldwide. It was the most prescribed herb in Ancient Egyptian, Roman, Greek, East China, and the West from the Former Han era. There are various beneficial effects of licorice root extracts, such as treating throat infections, tuberculosis, respiratory, liver diseases, antibacterial, anti-inflammatory, and immunodeficiency. On the other hand, traditional medicines are getting the attraction to treat many diseases. Therefore, it is vital to screen the medicinal plants to find the potential of new compounds to treat chronic diseases such as respiratory, cardiovascular, anticancer, hepatoprotective, etc. This work comprehensively reviews ethnopharmacological uses, phytochemistry, biological activities, clinical evidence, and the toxicology of licorice, which will serve as a resource for future clinical and fundamental studies. An attempt has been made to establish the pharmacological effect of licorice in different diseases. In addition, the focus of this review article is on the molecular mechanism of licorice extracts and their four flavonoids (isoliquiritigenin, liquiritigenin, lichalocone, and glabridin) pharmacologic activities. Licorice could be a natural alternative for current therapy to exterminate new emerging disorders with mild side effects. This review will provide systematic insights into this ancient drug for further development and clinical use.

Single-cell transcriptomic analyses of cardiac immune cells reveal that Rel-driven CD72-positive macrophages induce cardiomyocyte injury

AIMS

The goal of our study was to investigate the heterogeneity of cardiac macrophages (CMφs) in mice with transverse aortic constriction (TAC) via single-cell sequencing and identify a subset of macrophages associated with heart injury.

METHODS AND RESULTS

We selected all CMφs from CD45+ cells using single-cell mRNA sequencing data. Through dimension reduction, clustering and enrichment analyses, CD72hi CMφs were identified as a subset of proinflammatory macrophages. The pseudotime trajectory and ChIP-Seq analyses identified Rel as the key transcription factor that induces CD72hi CMφ differentiation. Rel KD and Rel-/- bone marrow chimera mice subjected to TAC showed features of mitigated cardiac injury, including decreased levels of cytokines and ROS, which prohibited cardiomyocyte death. The transfer of adoptive Rel-overexpressing monocytes and CD72hi CMφ injection directly aggravated heart injury in the TAC model. The CD72hi macrophages also exerted proinflammatory and cardiac injury effects associated with myocardial infarction (MI). In humans, patients with heart failure exhibit increased CD72hi CMφ levels following dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM).

CONCLUSION

Bone marrow-derived, Rel-mediated CD72hi macrophages play a proinflammatory role, induce cardiac injury and, thus, may serve as a therapeutic target for multiple cardiovascular diseases.

TRANSLATIONAL PERSPECTIVE

Heart failure (HF) imposes an enormous clinical and economic burden worldwide and presents limited therapeutic approaches. Given the close association between inflammation and adverse outcomes, proinflammatory immune cells are considered potential therapeutic targets for HF treatment. The present studies identified a specific macrophage subset associated with myocardial injury, which may provide an alternative approach for treating cardiovascular diseases.

Artificial Intelligence in Nutrients Science Research: A Review

Artificial intelligence (AI) as a branch of computer science, the purpose of which is to imitate thought processes, learning abilities and knowledge management, finds more and more applications in experimental and clinical medicine. In recent decades, there has been an expansion of AI applications in biomedical sciences. The possibilities of artificial intelligence in the field of medical diagnostics, risk prediction and support of therapeutic techniques are growing rapidly. The aim of the article is to analyze the current use of AI in nutrients science research. The literature review was conducted in PubMed. A total of 399 records published between 1987 and 2020 were obtained, of which, after analyzing the titles and abstracts, 261 were rejected. In the next stages, the remaining records were analyzed using the full-text versions and, finally, 55 papers were selected. These papers were divided into three areas: AI in biomedical nutrients research (20 studies), AI in clinical nutrients research (22 studies) and AI in nutritional epidemiology (13 studies). It was found that the artificial neural network (ANN) methodology was dominant in the group of research on food composition study and production of nutrients. However, machine learning (ML) algorithms were widely used in studies on the influence of nutrients on the functioning of the human body in health and disease and in studies on the gut microbiota. Deep learning (DL) algorithms prevailed in a group of research works on clinical nutrients intake. The development of dietary systems using AI technology may lead to the creation of a global network that will be able to both actively support and monitor the personalized supply of nutrients.

Arctigenin alleviates myocardial infarction injury through inhibition of the NFAT5-related inflammatory phenotype of cardiac macrophages/monocytes in mice

In this study, we screened potential natural compounds for the treatment of myocardial infarction (MI) and explored the underlying mechanisms. We built three machine learning models to screen the potential compounds. qPCR, flow cytometry, immunohistochemistry, and immunofluorescence analyses were applied to analyze the pharmacological effects of the compounds on macrophages/monocytes in vivo and in vitro. Arctigenin (AG) was selected as a candidate, and echocardiography, Masson's trichrome staining, and TUNEL staining were utilized to detect the effect of AG on MI in vivo. Transcriptome analysis and subsequent bioinformatics analyses were performed to predict the target of the selected compound. Western blot and luciferase reporter assays were used to confirm the target and mechanism of AG. The reversibility of the effects of AG were verified through overexpression of NFAT5. The results showed that AG can improve cardiac injury after MI by reducing infarct size, improving heart function, and inhibiting cardiac death. In addition, AG suppresses inflammatory macrophages/monocytes and proinflammatory cytokines in vivo and in vitro. Transcriptomic and biological experiments revealed that AG modulates macrophage polarization via the NFAT5-induced signaling pathway. Therefore, our data suggest that AG can improve MI by inhibiting the inflammatory phenotype of macrophages/monocytes through targeting of NFAT5.

Natural constituents from food sources: potential therapeutic agents against muscle wasting

Skeletal muscle wasting is highly correlated with not only reduced quality of life but also higher morbidity and mortality. Although an increasing number of patients are suffering from various kinds of muscle atrophy and weakness, there is still no effective therapy available, and skeletal muscle is considered as an under-medicated organ. Food provided not only essential macronutrients but also functional substances involved in the modulation of the physiological systems of our body. Natural constituents from commonly consumed dietary plants, either extracts or compounds, have attracted more and more attention to be developed as agents for preventing and treating muscle wasting due to their safety and effectiveness, as well as structural diversity. This review provides an overview of the mechanistic aspects of muscle wasting, and summarizes the extracts and compounds from food sources as potential therapeutic agents against muscle wasting.

Hispaglabridin B, a constituent of liquorice identified by a bioinformatics and machine learning approach, relieves protein-energy wasting by inhibiting forkhead box O1

BACKGROUND AND PURPOSE

Liquorice is the root of Glycyrrhiza glabra, which is a popular food in Europe and China that has previously shown benefits for skeletal fatigue and nutrient metabolism. However, the mechanism and active ingredients remain largely unclear. The aim of this study was to investigate the active ingredients of liquorice for muscle wasting and elucidate the underlying mechanisms.

EXPERIMENTAL APPROACH

RNA-Seq and bioinformatics analysis were applied to predict the main target of liquorice. A machine learning model and a docking tool were used to predict active ingredients. Isotope labelling experiments, immunostaining, Western blots, qRT-PCR, ChIP-PCR and luciferase reporters were utilized to test the pharmacological effects in vitro and in vivo. The reverse effects were verified through recombination-based overexpression.

KEY RESULTS

The liposoluble constituents of liquorice improved muscle wasting by inhibiting protein catabolism and fibre atrophy. We further identified FoxO1 as the target of liposoluble constituents of liquorice. In addition, hispaglabridin B (HB) was predicted as an inhibitor of FoxO1. Further studies determined that HB improved muscle wasting by inhibiting catabolism in vivo and in vitro. HB also markedly suppressed the transcriptional activity of FoxO1, with decreased expression of the muscle-specific E3 ubiquitin ligases MuRF1 and Atrogin-1.

CONCLUSIONS AND IMPLICATIONS

HB can serve as a novel natural food extract for preventing muscle wasting in chronic kidney disease and possibly other catabolic conditions.