S-allyl-glutathione improves experimental liver fibrosis by regulating Kupffer cell activation in rats

Selenium nanoparticles: Properties, preparation methods, and therapeutic applications

Selenium nanoparticles (SeNPs) are a unique type of nano-sized elemental selenium that have recently found wide application in biomedicine. It has been shown that the properties of SeNPs can be varied by different fabrication methods. Moreover, SeNPs have various therapeutic effects in medical applications due to their excellent biological and adaptable physical properties. At the same time, SeNPs can be used as a carrier medium for various therapeutic substances, which can bring out the full curative effects of the drugs. In this review, the differences in bioactivity properties of SeNPs prepared from different substances were reviewed; the therapeutic effects and mechanisms of SeNPs in cancer, inflammation, neurodegenerative diseases, diabetes, reproductive diseases, cardiovascular diseases, and other diseases were discussed; and the importance of the development of SeNPs was further emphasized.

Single-cell transcriptome reveals effects of semaglutide on non-cardiomyocytes of obese mice

Non-cardiomyocytes (nonCMs) play an important part in cardiac fibrosis pathophysiology, but the underlying molecular pathways are unknown. Semaglutide has cardioprotective properties, but it is still unclear whether it helps with cardiac fibrosis and what the processes are. The goal of this study is to use single cell transcriptomics approaches to investigate the molecular mechanism of semaglutide's cardioprotective action in obese mice. We found 15 non-CMs, with fibroblasts making up the majority of them. We found eight DEGs that altered significantly following semaglutide treatment by screening for differentially expressed genes (DEGs). DEGs were shown to have biological activities primarily related to extracellular matrix and collagen synthesis and distribution, with Serpinh1 and Pcolce expression being the most dramatically altered. Serpinh1 and Pcolce were mostly found in fibroblasts, which play a key role in the fibrosis of the heart. Furthermore, we discovered that semaglutide lowered cardiac collagen content and alleviated obesity-induced ventricular wall hypertrophy. As a result, our findings show that Serpinh1 and Pcolce, which are expressed by fibroblasts, may play a role in the development of obese cardiac fibrosis. By reducing Serpinh1 and Pcolce expression and delaying cardiac fibrosis, semaglutide may have a cardioprotective effect.

Macrophage Polarization and Its Role in Liver Disease

Macrophages are important immune cells in innate immunity, and have remarkable heterogeneity and polarization. Under pathological conditions, in addition to the resident macrophages, other macrophages are also recruited to the diseased tissues, and polarize to various phenotypes (mainly M1 and M2) under the stimulation of various factors in the microenvironment, thus playing different roles and functions. Liver diseases are hepatic pathological changes caused by a variety of pathogenic factors (viruses, alcohol, drugs, etc.), including acute liver injury, viral hepatitis, alcoholic liver disease, metabolic-associated fatty liver disease, liver fibrosis, and hepatocellular carcinoma. Recent studies have shown that macrophage polarization plays an important role in the initiation and development of liver diseases. However, because both macrophage polarization and the pathogenesis of liver diseases are complex, the role and mechanism of macrophage polarization in liver diseases need to be further clarified. Therefore, the origin of hepatic macrophages, and the phenotypes and mechanisms of macrophage polarization are reviewed first in this paper. It is found that macrophage polarization involves several molecular mechanisms, mainly including TLR4/NF-κB, JAK/STATs, TGF-β/Smads, PPARγ, Notch, and miRNA signaling pathways. In addition, this paper also expounds the role and mechanism of macrophage polarization in various liver diseases, which aims to provide references for further research of macrophage polarization in liver diseases, contributing to the therapeutic strategy of ameliorating liver diseases by modulating macrophage polarization.

Hepatic macrophages: Key players in the development and progression of liver fibrosis

Hepatic fibrosis is a common pathological process involving persistent liver injury with various etiologies and subsequent inflammatory responses that occur in chronic liver diseases. If left untreated, liver fibrosis can progress to liver cirrhosis, hepatocellular carcinoma and eventually, liver failure. Unfortunately, to date, there is no effective treatment for liver fibrosis, with the exception of liver transplantation. Although the pathophysiology of liver fibrosis is multifactorial and includes the activation of hepatic stellate cells, which are known to drive liver fibrogenesis, hepatic macrophages have emerged as central players in the development of liver fibrosis and regression. Hepatic macrophages, which consist of resident macrophages (Kupffer cells) and monocyte-derived macrophages, have been shown to play an intricate role in the initiation of inflammatory responses to liver injury, progression of fibrosis, and promotion of fibrosis resolution. These features have made hepatic macrophages uniquely attractive therapeutic targets in the fight against hepatic fibrosis. In this review, we synthesised the literature to highlight the functions and regulation of heterogeneity in hepatic macrophages. Furthermore, using the existing findings, we attempt to offer insights into the molecular mechanisms underlying the phenotypic switch from fibrogenic macrophages to restorative macrophages, the regulation of heterogeneity, and modes of action for hepatic macrophages. A better understanding of these mechanisms may guide the development of novel anti-fibrotic therapies (eg macrophage subset-targeted treatments) to combat liver fibrosis in the future.

Inhibition of glutathione and s-allyl glutathione on pancreatic lipase: Analysis through in vitro kinetics, fluorescence spectroscopy and in silico docking

Inhibition of pancreatic lipase (PL) is considered one of the important therapeutic interventions against obesity. In the present study, the inhibition of porcine (mammalian) PL (PPL) by two tripeptides glutathione (GSH) and s-allyl glutathione (SAG) was studied. In vitro kinetic analysis was done to determine the inhibition of GSH and SAG against PPL. The binding of GSH and SAG with PPL was elucidated by fluorescence spectroscopy analysis. Docking and molecular dynamics (MD) simulation analysis was carried out to understand the intermolecular interaction between both GSH and SAG with PPL as well as human PL (HPL). Both GSH and SAG inhibited PPL in mixed non-competitive manner. The IC₅₀ value for GSH and SAG against PPL was found to be 2.97 and 6.4 mM, respectively. Both GSH and SAG quenched the intrinsic fluorescence of PPL through static quenching that is through forming complex with the PPL. SAG and GSH interacted with amino acids involved in catalysis of both PPL and HPL. MD simulation showed interactions of SAG and GSH with both PPL and HPL were stable. These results would lead to the further studies and application of GSH and SAG against obesity through inhibition of PL.

Suberoylanilide hydroxamic acid alleviates orthotopic liver transplantation‑induced hepatic ischemia‑reperfusion injury by regulating the AKT/GSK3β/NF‑κB and AKT/mTOR pathways in rat Kupffer cells

Multiple mechanisms are involved in regulating hepatic ischemia-reperfusion injury (IRI), in which Kupffer cells (KCs), which are liver-resident macrophages, play critical roles by regulating inflammation and the immune response. Suberoylanilide hydroxamic acid (SAHA), a pan-histone deacetylase inhibitor, has anti-inflammatory effects and induces autophagy. To investigate whether SAHA ameliorates IRI and the mechanisms by which SAHA exerts its effects, an orthotopic liver transplantation (OLT) rat model was established after treatment with SAHA. The results showed that SAHA effectively ameliorated OLT-induced IRI by reducing M1 polarization of KCs through inhibition of the AKT/glycogen synthase kinase (GSK)3β/NF-κB signaling pathway. Furthermore, the present study found that SAHA upregulates autophagy 5 protein (ATG5)/LC3B in KCs through the AKT/mTOR signaling pathway and inhibition of autophagy by knockdown of ATG5 in KCs partly impaired the protective effect of SAHA on IR-injured liver. Therefore, the current study demonstrated that SAHA reduces M1 polarization of KCs by inhibiting the AKT/GSK3β/NF-κB pathway and upregulates autophagy in KCs through the AKT/mTOR signaling pathway, which both alleviate OLT-induced IRI. The present study revealed that SAHA may be a novel treatment for the amelioration of OLT-induced IRI.

Natural Sulfur-Containing Compounds: An Alternative Therapeutic Strategy against Liver Fibrosis

Liver fibrosis is a pathophysiologic process involving the accumulation of extracellular matrix proteins as collagen deposition. Advanced liver fibrosis can evolve in cirrhosis, portal hypertension and often requires liver transplantation. At the cellular level, hepatic fibrosis involves the activation of hepatic stellate cells and their transdifferentiation into myofibroblasts. Numerous pro-fibrogenic mediators including the transforming growth factor-β1, the platelet-derived growth factor, endothelin-1, toll-like receptor 4, and reactive oxygen species are key players in this process. Knowledge of the cellular and molecular mechanisms underlying hepatic fibrosis development need to be extended to find novel therapeutic strategies. Antifibrotic therapies aim to inhibit the accumulation of fibrogenic cells and/or prevent the deposition of extracellular matrix proteins. Natural products from terrestrial and marine sources, including sulfur-containing compounds, exhibit promising activities for the treatment of fibrotic pathology. Although many therapeutic interventions are effective in experimental models of liver fibrosis, their efficacy and safety in humans are largely unknown. This review aims to provide a reference collection on experimentally tested natural anti-fibrotic compounds, with particular attention on sulfur-containing molecules. Their chemical structure, sources, mode of action, molecular targets, and pharmacological activity in the treatment of liver disease will be discussed.

Gastric cancer and Hedgehog signaling pathway: emerging new paradigms

Ever since its initial discovery in Drosophila, hedgehog signaling has been linked to foregut development, The mammalian genome expresses three Hedgehog paralogues, sonic hedgehog (Shh), Indian Hedgehog, and desert hedgehog. In the mucosa of the embryonic and adult foregut, Shh expression is the highest. It has now become clear that hedgehog signaling is of pivotal importance in gastric homeostasis. Aberrant activation of hedgehog signaling is associated with a range of pathological consequences including various cancers. Also in gastric cancer, clinical and preclinical data support a role of Hedgehog signaling in neoplastic transformation, and gastrointestinal cancer development, also through cancer stroma interaction. Technological advance are facilitating monitoring Hedgehog signaling broadening options for the more efficient screening of individuals predisposed to eventually developing gastric cancer and targeting Hedgehog signaling may provide opportunities for prophylactic therapy once atrophic gastritis develops. Nevertheless, convincing evidence that Hedgehog antagonists are of clinically useful in the context of gastric cancer is still conspicuously lacking. Here we analyze review the role of Hedgehog in gastric physiology and the potential usefulness of targeting Hedgehog signaling in gastric cancer.

Macrophage colony-stimulating factor increases hepatic macrophage content, liver growth, and lipid accumulation in neonatal rats

Signaling via the colony-stimulating factor 1 receptor (CSF1R) controls the survival, differentiation, and proliferation of macrophages. Mutations in CSF1 or CSF1R in mice and rats have pleiotropic effects on postnatal somatic growth. We tested the possible application of pig CSF1-Fc fusion protein as a therapy for low birth weight (LBW) at term, using a model based on maternal dexamethasone treatment in rats. Neonatal CSF1-Fc treatment did not alter somatic growth and did not increase the blood monocyte count. Instead, there was a substantial increase in the size of liver in both control and LBW rats, and the treatment greatly exacerbated lipid droplet accumulation seen in the dexamethasone LBW model. These effects were reversed upon cessation of treatment. Transcriptional profiling of the livers supported histochemical evidence of a large increase in macrophages with a resident Kupffer cell phenotype and revealed increased expression of many genes implicated in lipid droplet formation. There was no further increase in hepatocyte proliferation over the already high rates in neonatal liver. In conclusion, treatment of neonatal rats with CSF1-Fc caused an increase in liver size and hepatic lipid accumulation, due to Kupffer cell expansion and/or activation rather than hepatocyte proliferation. Increased liver macrophage numbers and expression of endocytic receptors could mitigate defective clearance functions in neonates. NEW & NOTEWORTHY This study is based on extensive studies in mice and pigs of the role of CSF1/CSF1R in macrophage development and postnatal growth. We extended the study to neonatal rats as a possible therapy for low birth weight. Unlike our previous studies in mice and pigs, there was no increase in hepatocyte proliferation and no increase in monocyte numbers. Instead, neonatal rats treated with CSF1 displayed reversible hepatic steatosis and Kupffer cell expansion.