3D analysis of microvasculature in murine liver fibrosis models using synchrotron radiation-based microtomography

Schisantherin D from Schisandra chinensis (Turcz.) Baill. exhibits anti-liver fibrosis capacity via modulating ETBR involved signaling, an in vitro and in vivo study

Excess levels of chemical hepatotoxicants (alcohol, aflatoxin B1), oxidative drugs (acetaminophen) and some cytokines (ET-1, TGF-β1) can induce chronic or acute liver injury. After these, the severe hepatic disease, especially the liver fibrosis (LF) occurs without taking measures, which brings threat to human health. The dibenzocyclooctadiene lignans of S. chinensis (SCDLs) were found to act as the hepatoprotective components via blocking endothelin B receptor (ETBR). While study on its anti-LF mechanisms especially for its refined compound of schisantherin D (SC-D) is still a lack. So this study aims to investigate the anti-fibrosis effect of SC-D with in vitro and in vivo assays. Bioinformatics analysis revealed the close relations of ETBR to Smad2, Smad3, Nrf2, etc. in LF-related signaling pathways (such as TGF-β/Smad and Nrf2/ARE). Histopathological staining on livers showed the recovery trend in SC-D treated LF mice. SC-D also modulated expressions of ETBR and fibrosis or anti-oxidative related proteins (such as TIMP1, p-Smad2/3, Nrf2, Smad7, etc.) in LF mice livers. Serum levels of TNF-α, COLI, ALT, AST and LDH in SC-D treated mice were also downregulated compared with LF mice, and upregulated expression of GSH. In vitro studies, SC-D also modulated expressions of LF-related proteins to the normal tendency in LX-2 cell, while weakened its anti- LX-2 proliferation effect by transfections of si-Smad7 or si-Nrf2. Accordingly the anti-LF approach of SC-D showed relations with modulating ETBR linked fibrosis and anti-oxidative related signaling. Also, Smad7 and Nrf2 might be the key factors for SC-D mediated anti-LF effect.

Effectiveness of cell- and colony stimulating factor-based therapy for liver cirrhosis: a network meta-analysis of randomized controlled trials

BACKGROUND AIMS

Cirrhosis is the 11th leading cause of death worldwide. Because of the limitations of liver transplantation, cell- and granulocyte colony-stimulating factor (G-CSF)-based therapies are considered potential treatment methods. This work analyzes the effectiveness of cell- and G-CSF-based therapies by network meta-analysis.

METHODS

A literature search was performed in four databases from inception to September 10, 2021. Registered randomized controlled trials (RCTs) evaluating cell-based therapies and/or G-CSF-based therapies for cirrhosis patients were included. Traditional and network meta-analyses were analyzed in terms of survival, model for end-stage liver disease (MELD) score, Child-Turcotte-Pugh (CTP) score, alanine aminotransferase levels and aspartate aminotransferase levels.

RESULTS

Twenty-four studies were included in this analysis. The results showed that G-CSF-based therapies (odds ratio [OR], 2.38, 95% confidence interval [CI], 1.49-3.79, P < 0.01) and cell-based therapies (OR, 1.54, 95% CI, 1.00-2.40, P = 0.048) improved the transplantation-free survival rate compared with standard medical treatment. Network analysis results showed that G-CSF combined with erythropoietin (EPO) and growth hormone (GH) had a therapeutic advantage, and cell-based therapy with mononuclear cell (MNC) hepatic artery injection and intravenous mesenchymal stem cells (MSCs) combined with G-CSF also had a relative advantage in terms of survival outcome. For the MELD score, G-CSF plus GH and MSC portal vein injection had relative advantages. G-CSF plus GH and G-CSF plus EPO had advantages in terms of CTP scores. The included strategies demonstrated no obvious improvement in liver injury indicators.

CONCLUSIONS

Cell-based therapy has potential therapeutic effects for liver cirrhosis. Among cell-based therapies, intravenous MSCs and hepatic artery injection of MNCs have advantageous therapeutic effects. The use of G-CSF was also noted in regimens that improved survival outcomes. However, more well-designed, large-scale RCTs are needed to confirm this conclusion.

Multiscale reconstruction of various vessels in the intact murine liver lobe

The liver contains a variety of vessels and participates in miscellaneous physiological functions. While past studies generally focused on certain hepatic vessels, we simultaneously obtained all the vessels and cytoarchitectural information of the intact mouse liver lobe at single-cell resolution. Here, taking structural discrepancies of various vessels into account, we reconstruct and visualize the portal vein, hepatic vein, hepatic artery, intrahepatic bile duct, intrahepatic lymph of an intact liver lobe and peribiliary plexus in its selected local areas, providing a technology roadmap for studying the fine hepatic vascular structures and their spatial relationship, which will help research into liver diseases and evaluation of medical efficacies in the future.

Use of the volume-averaged Murray's deviation method for the characterization of branching geometry in liver fibrosis: a preliminary study on vascular circulation

Background

Vascular changes in liver fibrosis can result in increased intrahepatic vascular resistance and impaired blood circulation. This can hinder the recovery from fibrosis and may eventually lead to portal hypertension, a major cirrhosis complication. This report proposed a volume-averaged Murray's deviation method to characterize intrahepatic circulation in the liver during fibrosis and its subsequent regression via X-ray phase-contrast computed tomography (PCCT).

Methods

Liver fibrosis was induced in 24 Sprague-Dawley rats by exposure to carbon tetrachloride (CCl₄) for up to 10 weeks, after which, spontaneous regression commenced and continued until week 30. High-resolution three-dimensional (3D) imaging of the livers was performed with PCCT. The values of Murray's deviation based on the volume-averaged and the conventional diameter-based methods were compared. After that, the intrahepatic circulation at different stages of fibrosis was evaluated using the volume-averaged method. The increase in collagen during liver fibrosis was assessed by pathological analyses.

Results

A comparison of the 2 methods showed that with an increase in the number of diameter measurements, the value of Murrary's deviation obtained using the diameter-based method gradually approaches those of the volume-averaged method, with minimal variations. The value of Murray's deviation increased with the development of fibrosis. After reversal, the value rapidly decreased and approached that of the normal state in both the main branches (1.05±0.17, 1.17±0.21, 1.34±0.18, and 1.17±0.19 in the normal, moderate, severe, and regressive groups, respectively; P<0.05 between the severe group and other groups) and the small branches (1.05±0.09, 1.42±0.48, 1.79±0.57, and 1.18±0.28 in the normal, moderate, severe, and regressive group, respectively; P<0.05 between adjacent groups). An analysis of Murray's deviation and the pathological results showed that the vascular circulation in this disease model was consistent with the progression and recovery from fibrosis.

Conclusions

This study showed the validity of the volume-averaged method for calculating Murray's deviation and demonstrated that it could accurately evaluate the blood circulation state of the liver during fibrosis and its subsequent regression. Thus, the volume-averaged method of calculating Murray's deviation may be an objective and valuable staging criterion to evaluate intrahepatic circulation during liver fibrosis.

Alternative Vascularization Mechanisms in Tumor Resistance to Therapy

Simple Summary

Tumors rely on blood vessels to grow and metastasize. Malignant tumors can employ different strategies to create a functional vascular network. Tumor cells can use normal processes of vessel formation but can also employ cancer-specific mechanisms, by co-opting normal vessels present in tissues or by turning themselves into vascular cells. These different types of tumor vessels have specific molecular and functional characteristics that profoundly affect tumor behavior and response to therapies, including drugs targeting the tumor vasculature (antiangiogenic therapies). In this review, we discuss how vessels formed by different mechanisms affect the intrinsic sensitivity of tumors to therapy and, on the other hand, how therapies can affect tumor vessel formation, leading to resistance to drugs, cancer recurrence, and treatment failure. Potential strategies to avoid vessel-mediated resistance to antineoplastic therapies will be discussed.

Abstract

Blood vessels in tumors are formed through a variety of different mechanisms, each generating vessels with peculiar structural, molecular, and functional properties. This heterogeneity has a major impact on tumor response or resistance to antineoplastic therapies and is now emerging as a promising target for strategies to prevent drug resistance and improve the distribution and efficacy of antineoplastic treatments. This review presents evidence of how different mechanisms of tumor vessel formation (vasculogenesis, glomeruloid proliferation, intussusceptive angiogenesis, vasculogenic mimicry, and vessel co-option) affect tumor responses to antiangiogenic and antineoplastic therapies, but also how therapies can promote alternative mechanisms of vessel formation, contributing to tumor recurrence, malignant progression, and acquired drug resistance. We discuss the possibility of tailoring treatment strategies to overcome vasculature-mediated drug resistance or to improve drug distribution and efficacy.