Progress in drug delivery system for fibrosis therapy

ROS-responsive injectable hydrogels loaded with exosomes carrying miR-4500 reverse liver fibrosis

The reversal of liver fibrosis requires effective strategies to reduce oxidative stress and inhibition of hepatic stellate cell (HSC) activation. MiR-4500 regulates pathological angiogenesis and collagen mRNA stability, with the potential to inhibit fibrosis. Herein, we explored the inhibition of HSC activation in vitro by exosomes (Exos) carrying miR-4500 and encapsulated ExosmiR-4500 in an intelligent injectable hydrogel with biological activity and reactive oxygen species (ROS) responsiveness for application in oxidative stress environments. Briefly, reversible boronic ester bonds were integrated into gelatin-based hydrogels through dynamic crosslinking of quaternized chitosan (QCS) and 4-carboxyphenylboronic acid (CPBA)-modified gelatin. The QCS-CPBA-Gelatin (QCG) hydrogel scavenged excess ROS from the local microenvironment and released ExosmiR-4500 through the dissociation of boronic ester bonds, providing a favorable microenvironment and in situ sustained-release drug delivery system for ExosmiR-4500. The results showed that QCG@ExosmiR-4500 hydrogel has biocompatibility, biodegradability, and slow-release ability, which could effectively clear ROS and inhibit HSC activation and pathological angiogenesis in vitro and in vivo. Furthermore, transcriptome analysis suggests that the pharmacological mechanism of the QCG@ExosmiR-4500 hydrogel is mainly related to anti-oxidation, anti-angiogenesis, anti-fibrosis processes, and signaling pathways. Thus, our study demonstrates that an intelligently responsive ExosmiR-4500 delivery system based on injectable hydrogels is a promising strategy for the treatment of liver fibrosis.

The application and prospects of drug delivery systems in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease primarily affecting elderly individuals aged >65 years and has a poor prognosis. No effective treatment is currently available for IPF. The two antipulmonary fibrosis drugs nintedanib and pirfenidone approved by the FDA in the United States have somewhat decelerated IPF progression. However, the side effects of these drugs can lead to poor patient tolerance and compliance with the medications. Researchers have recently developed various methods for IPF treatment, such as gene silencing and pathway inhibitors, which hold great promise in IPF treatment. Nevertheless, the nonselectivity and nonspecificity of drugs often affect their efficacies. Drug delivery systems (DDS) are crucial for delivering drugs to specific target tissues or cells, thereby minimizing potential side effects, enhancing drug bioavailability, and reducing lung deposition. This review comprehensively summarizes the current state of DDS and various delivery strategies for IPF treatment (e.g., nano-delivery, hydrogel delivery, and biological carrier delivery) to completely expound the delivery mechanisms of different drug delivery carriers. Subsequently, the advantages and disadvantages of different DDS are fully discussed. Finally, the challenges and difficulties associated with the use of different DDS are addressed so as to accelerate their rapid clinical translation.

Dual-ligand-functionalized nanostructured lipid carriers as a novel dehydrocavidine delivery system for liver fibrosis therapy

BACKGROUND

Liver fibrosis is a common stage of various chronic liver diseases, often developing into liver cirrhosis, and even liver cancer. Activated hepatic stellate cells (aHSCs) have been shown to promote the development of liver fibrosis. Therefore, dual-targeted combination therapy for liver may be an effective strategy for the treatment of liver fibrosis.

PURPOSE

In this study, the novel nanostructured lipid carriers (GA&GalNH2-DC-NLCs) were prepared for Dehydrocavidine (DC), glycyrrhetinic acid (GA) and galactose-PEG2000-NH2 (GalNH2) were selected as targeted ligand-modified nanostructured lipid carriers (NLCs), which enables dual-targeting to the liver for the treatment of liver fibrosis.

STUDY DESIGN

To study the targeting effect of GA&GalNH2-DC-NLCs on liver and its therapeutic effect on liver fibrosis, we established aHSC-T6 cell model and rat model of liver fibrosis for study.

RESULTS

GA&GalNH2-DC-NLCs promoted drug liver targeting efficiency and apoptosis rate by upregulating the expression of Bax. It showed that compared with no and/or GA-modified NLCs and GalNH2-modified NLCs, GA&GalNH2-DC-NLCs exhibited less extracellular matrix (ECM) deposition, induced apoptosis of aHSCs, and stronger anti-fibrosis effects in vivo. This may be due the fact that GA or GalNH2-modifified NLCs simultaneously block HSCs activation and inhibit the IL-6/STAT3 pathway.

CONCLUSION

GA&GalNH2-DC-NLCs is thus a potential strategy for liver fibrosis treatment.

Aggregation-Induced Emission CN-Based Nanoparticles to Alleviate Hypoxic Liver Fibrosis via Triggering HSC Ferroptosis and Enhancing Photodynamic Therapy

Hypoxia can lead to liver fibrosis and severely limits the efficacy of photodynamic therapy (PDT). Herein, carbon nitride (CN)-based hybrid nanoparticles (NPs) VPSGCNs@TSI for light-driven water splitting were utilized to solve this problem. CNs were doped with selenide glucose (Se-glu) to enhance their red/NIR region absorption. Then, vitamin A-poly(ethylene glycol) (VA-PEG) fragments and aggregation-induced emission (AIE) photosensitizers TSI were introduced into Se-glu-doped CN NPs (VPSGCNs) to construct VPSGCNs@TSI NPs. The introduction of VA-PEG fragments enhanced the targeting of the NPs to activated hepatic stellate cells (HSCs) and reduced their toxicity to ordinary liver cells. VPSGCN units could trigger water splitting to generate O2 under 660 nm laser irradiation, improve the hypoxic environment of the fibrosis site, downregulate HIF-1α expression, and activate HSC ferroptosis via the HIF-1α/SLC7A11 pathway. In addition, generated O2 could also increase the reactive oxygen species (ROS) production of TSI units in a hypoxic environment, thereby completely reversing hypoxia-triggered PDT resistance to enhance the PDT effect. The combination of water-splitting materials and photodynamic materials showed a 1 + 1 > 2 effect in increasing oxygen levels in liver fibrosis, promoting ferroptosis of activated HSCs and reversing PDT resistance caused by hypoxia.

An updated review of the pharmacological effects and potential mechanisms of hederagenin and its derivatives

Hederagenin (HG) is a natural pentacyclic triterpenoid that can be isolated from various medicinal herbs. By modifying the structure of HG, multiple derivatives with superior biological activities and safety profiles have been designed and synthesized. Accumulating evidence has demonstrated that HG and its derivatives display multiple pharmacological activities against cancers, inflammatory diseases, infectious diseases, metabolic diseases, fibrotic diseases, cerebrovascular and neurodegenerative diseases, and depression. Previous studies have confirmed that HG and its derivatives combat cancer by exerting cytotoxicity, inhibiting proliferation, inducing apoptosis, modulating autophagy, and reversing chemotherapy resistance in cancer cells, and the action targets involved mainly include STAT3, Aurora B, KIF7, PI3K/AKT, NF-κB, Nrf2/ARE, Drp1, and P-gp. In addition, HG and its derivatives antagonize inflammation through inhibiting the production and release of pro-inflammatory cytokines and inflammatory mediators by regulating inflammation-related pathways and targets, such as NF-κB, MAPK, JAK2/STAT3, Keap1-Nrf2/HO-1, and LncRNA A33/Axin2/β-catenin. Moreover, anti-pathogen, anti-metabolic disorder, anti-fibrosis, neuroprotection, and anti-depression mechanisms of HG and its derivatives have been partially elucidated. The diverse pharmacological properties of HG and its derivatives hold significant implications for future research and development of new drugs derived from HG, which can lead to improved effectiveness and safety profiles.

Prospective therapeutics for intestinal and hepatic fibrosis

Currently, there are no effective therapies for intestinal and hepatic fibrosis representing a considerable unmet need. Breakthroughs in pathogenesis have accelerated the development of anti-fibrotic therapeutics in recent years. Particularly, with the development of nanotechnology, the harsh environment of the gastrointestinal tract and inaccessible microenvironment of fibrotic lesions seem to be no longer considered a great barrier to the use of anti-fibrotic drugs. In this review, we comprehensively summarize recent preclinical and clinical studies on intestinal and hepatic fibrosis. It is found that the targets for preclinical studies on intestinal fibrosis is varied, which could be divided into molecular, cellular, and tissues level, although little clinical trials are ongoing. Liver fibrosis clinical trials have focused on improving metabolic disorders, preventing the activation and proliferation of hepatic stellate cells, promoting the degradation of collagen, and reducing inflammation and cell death. At the preclinical stage, the therapeutic strategies have focused on drug targets and delivery systems. At last, promising remedies to the current challenges are based on multi-modal synergistic and targeted delivery therapies through mesenchymal stem cells, nanotechnology, and gut-liver axis providing useful insights into anti-fibrotic strategies for clinical use.

Elevated Levels of Plasma Collagen Triple Helix Repeat Containing 1 (CTHRC1) Is Strongly Associated with eGFR and Albuminuria in Chronic Kidney Disease

Background: Chronic kidney disease (CKD) has various etiologies, making it impossible to fully understand its complex pathophysiology. Elevated levels of plasma creatinine, proteinuria, and albuminuria and declined eGFR are traits observed in CKD patients. The current study attempts to highlight the collagen triple helix repeat containing 1 (CTHRC1) protein as a putative blood biomarker for CKD in addition to existing recognized indicators of CKD progression. Methods: A total of 26 CKD patients and 18 healthy controls were enrolled in this study. Clinical characteristics and complete blood and biochemical analyses were collected, and human ELISA kits were used to detect possible CKD biomarkers. Results: The study’s findings showed that CTHRC1 correlates with key clinical markers of kidney function such as 24 h urine total protein, creatinine, urea, and uric acid. In addition, CTHRC1 demonstrated a strong significant difference (p ≤ 0.0001) between the CKD and control group. Conclusions: Our research demonstrates that the plasma level of CTHRC1 can distinguish between those with CKD and healthy patients. Plasma CTHRC1 levels may aid in the diagnosis of CKD given the current state of knowledge, and these results call for further investigation in a wider, more diverse patient group.

The well-developed actin cytoskeleton and Cthrc1 expression by actin-binding protein drebrin in myofibroblasts promote cardiac and hepatic fibrosis

Fibrosis is mainly triggered by inflammation in various tissues, such as heart and liver tissues, and eventually leads to their subsequent dysfunction. Fibrosis is characterized by the excessive accumulation of extracellular matrix proteins (e.g., collagens) produced by myofibroblasts. The well-developed actin cytoskeleton of myofibroblasts, one of the main features differentiating them from resident fibroblasts in tissues under inflammatory conditions, contributes to maintaining their ability to produce excessive extracellular matrix proteins. However, the molecular mechanisms via which the actin cytoskeleton promotes the production of fibrosis-related genes in myofibroblasts remain unclear. In this study, we found, via single-cell analysis, that developmentally regulated brain protein (drebrin), an actin-binding protein, was specifically expressed in cardiac myofibroblasts with a well-developed actin cytoskeleton in fibrotic hearts. Moreover, our immunocytochemistry analysis revealed that drebrin promoted actin cytoskeleton formation and myocardin-related transcription factor-serum response factor signaling. Comprehensive single-cell analysis and RNA-Seq revealed that the expression of collagen triple helix repeat containing 1 (Cthrc1), a fibrosis-promoting secreted protein, was regulated by drebrin in cardiac myofibroblasts via myocardin-related transcription factor-serum response factor signaling. Furthermore, we observed the profibrotic effects of drebrin exerted via actin cytoskeleton formation and the Cthrc1 expression regulation by drebrin in liver myofibroblasts (hepatic stellate cells). Importantly, RNA-Seq demonstrated that drebrin expression levels increased in human fibrotic heart and liver tissues. In summary, our results indicated that the well-developed actin cytoskeleton and Cthrc1 expression due to drebrin in myofibroblasts promoted cardiac and hepatic fibrosis, suggesting that drebrin is a therapeutic target molecule for fibrosis.

Effect of Pheretima aspergillum on reducing fibrosis: A systematic review and meta-analysis

Background: Pheretima aspergillum (common name: Earthworm, Chinese name: dilong) has been used in traditional Chinese medicine for thousands of years. Recently, a few scientific studies have investigated the antifibrotic effects of Dilong extract (DE) and produced controversial results. We conducted a meta-analysis to make an informed decision on the antifibrotic effects of Dilong extract. Methods: The studies on antifibrotic effects of Dilong extract published until July 2022 in the scientific databases [PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), VIP database for Chinese Technical Periodicals, SinoMed and WanFang database] were reviewed. The RevMan 5.4.1 software was used for standardized mean difference (SMD) analysis. Two researchers independently reviewed all the studies, and their quality was assessed using the Cochrane risk of bias tool. Results: A total of 325 studies were found in the scientific databases; however, only 13 studies met the criteria for analysis. Dilong extract treatment was associated with antifibrotic effects via inhibiting the transforming growth factor beta 1 (TGF-β1, SMD = -3.16, 95% CI: -4.18, -2.14, p < .00001) and alpha-smooth muscle actin (α-SMA: SMD = -2.57, 95% CI: -3.47, -1.66, p < .00001). Conclusion: Dilong extract effectively reduces tissue fibrosis; thus, further scientific studies should be conducted to investigate and develop it for clinical use. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022357141.

Long non-coding RNA lnc-CHAF1B-3 promotes renal interstitial fibrosis by regulating EMT-related genes in renal proximal tubular cells

Renal interstitial fibrosis (RIF) is a common pathological manifestation of chronic kidney diseases. Epithelial-mesenchymal transition (EMT) of tubular epithelial cells is considered a major cause of RIF. Although long non-coding RNAs (lncRNAs) are reportedly involved in various pathophysiological processes, the roles and underlying molecular mechanisms of lncRNAs in the progression of RIF are poorly understood. In this study, we investigated the function of lncRNAs in RIF. Microarray assays showed that expression of the lncRNA lnc-CHAF1B-3 (also called claudin 14 antisense RNA 1) was significantly upregulated in human renal proximal tubular cells by both transforming growth factor-β1 (TGF-β1) and hypoxic stimulation, accompanied with increased expression of EMT-related genes. Knockdown of lnc-CHAF1B-3 significantly suppressed TGF-β1-induced upregulated expression of collagen type I alpha 1, cadherin-2, plasminogen activator inhibitor-1, snail family transcriptional repressor I (SNAI1) and SNAI2. Quantitative reverse transcriptase PCR analyses of paraffin-embedded kidney biopsy samples from IgA nephropathy patients revealed lnc-CHAF1B-3 expression was correlated positively with urinary protein levels and correlated negatively with estimated glomerular filtration rate. In situ hybridization demonstrated that lnc-CHAF1B-3 is expressed only in proximal tubules. These findings suggest lnc-CHAF1B-3 affects the progression of RIF by regulating EMT-related signaling. Thus, lnc-CHAF1B-3 is a potential target in the treatment of RIF.

Design, synthesis and biological evaluation studies of novel anti-fibrosis agents bearing sulfoxide moiety

Fibrosis, a chronic disease with high morbidity and mortality, is mainly characterized by excessive accumulation of extracellular matrix (ECM). At present, pathogenesis of fibrosis is incompletely understood, and there is an urgent need to develop safe and effective drugs. In this study, we designed and synthesized a series of novel small-molecule compounds through structural modification and fragment hybridization. Among them, a potential anti-fibrosis drug compd.1 was founded to be able to dose-dependently down-regulate ACTA2 and CTGF mRNA levels in human hepatic stellate cells (LX-2) treated with TGF-β. In addition, compd.1 significantly improved the bridging fibrosis and collagen content in the CCl4-induced liver fibrosis mice model. Moreover, compd.1 reduced lung inflammation and fibrotic area in bleomycin-induced pulmonary fibrosis mice model. These findings suggested that compd.1 is a promising candidate for further anti-fibrosis researches, and extended chemical space might help us to explore better anti-fibrosis drug.

Conformationally Restricted Dipeptide-Based Nanoparticles for Delivery of siRNA in Experimental Liver Cirrhosis

Liver cirrhosis is a major health problem with multiple associated complications. The presently available drug delivery systems showed moderate site-specific delivery of antifibrotic molecules to the diseased liver; therefore, research on more effective and selective delivery systems in the context of liver cirrhosis remains a necessity in clinical investigation. The aim of the present study was to develop a peptide-based targeted nanocarrier to deliver an oligonucleotide to the hepatic sinusoidal and perivascular regions of the cirrhotic liver. We have synthesized and characterized a conformationally restricted targeted pentapeptide (RΔFRGD), which contains an unnatural amino acid, α,β-dehydrophenylalanine (ΔF). The RΔFRGD self-assembled into spherical nanoparticles (NPs) and was characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Next, we investigated the delivery potential of the pentapeptide-based NPs to make a stable complex with a well-established small interference RNA and studied its site-specific delivery in experimental liver cirrhosis. We used siNR4A1 of the orphan nuclear receptor 4A1 (NR4A1), a well-known regulatory checkpoint for controlling liver fibrosis. Peptide NPs and their complex with siNR4A1 showed high biocompatibility against various mammalian cell lines. Hepatic tissue biodistribution analysis illustrated that targeted NPs predominantly accumulated in the cirrhotic liver compared to normal rats, specifically in sinusoidal and perivascular areas. A significant downregulation of the NR4A1 mRNA expression (-70%) andlower levels of the NR4A1/GAPDH ratio (-55%) were observed in the RΔFRGD-siNR4A1 nanocomplex-treated group in comparison to the RΔFRGD-vehicle group (RΔFRGD-Veh) at the gene and protein levels, respectively. In addition, in vivo inhibition of NR4A1 produced a significant aggravation in hepatic fibrosis compared with siRNA-vehicle-treated rats (+41% in the MT stain). The novel pentapeptide-based targeted delivery system can be further evaluated and validated for therapeutic purposes in various pathological conditions.

D-Carvone Attenuates CCl4-Induced Liver Fibrosis in Rats by Inhibiting Oxidative Stress and TGF-ß 1/SMAD3 Signaling Pathway

D-carvone is a natural monoterpene found in abundance in the essential oil of aromatic medicinal plants with a wide range of pharmacological values. However, the impact of D-carvone on liver fibrosis remains unclear. This study aimed to evaluate the anti-fibrotic potential of D-carvone in a rat model of liver fibrosis and to clarify the possible underlying mechanisms. Liver fibrosis was induced in rats by carbon tetrachloride, CCl₄ (2.5 mL/kg, interperitoneally every 72 h for 8 weeks). Oral treatment of rats with D-carvone (50 mg/kg, daily) started on the 3rd week of CCl₄ administration. D-carvone significantly enhanced liver functions (ALT, AST), oxidant/antioxidant status (MDA, SOD, GSH, total antioxidant capacity; TAC), as well as histopathological changes. Moreover, D-carvone effectively attenuated the progression of liver fibrosis, evident by the decreased collagen deposition and fibrosis score by Masson trichrome staining (MT) and α-SMA protein expression. Moreover, D-carvone administration resulted in a significant downregulation of the pro-fibrogenic markers TGF-β1 and SMAD3 and upregulation of MMP9. These findings reveal the anti-fibrotic effect of D-carvone and suggest regulation of the TGF-β1/SMAD3 pathway, together with the antioxidant activity as a mechanistic cassette, underlines this effect. Therefore, D-carvone could be a viable candidate for inhibiting liver fibrosis and other oxidative stress-related hepatic diseases. Clinical studies to support our hypothesis are warranted.

Nanotechnology in Drug Delivery for Liver Fibrosis

Liver fibrosis is a reversible disease course caused by various liver injury etiologies, and it can lead to severe complications, such as liver cirrhosis, liver failure, and even liver cancer. Traditional pharmacotherapy has several limitations, such as inadequate therapeutic effect and side effects. Nanotechnology in drug delivery for liver fibrosis has exhibited great potential. Nanomedicine improves the internalization and penetration, which facilitates targeted drug delivery, combination therapy, and theranostics. Here, we focus on new targets and new mechanisms in liver fibrosis, as well as recent designs and development work of nanotechnology in delivery systems for liver fibrosis treatment.

Resolving hepatic fibrosis via suppressing oxidative stress and an inflammatory response using a novel hyaluronic acid modified nanocomplex

Hepatic fibrosis remains a serious threat to human health globally and there are no effective antifibrotic pharmacotherapeutic strategies, to date. Upon the activation of hepatic stellate cells, excess deposition of the extracellular matrix occurs, acting as a trigger that generates reactive oxygen species and an inflammatory response, thereby exacerbating the development of hepatic fibrosis and inflammation. In this study, we incorporated an idea that targets key pathways for developing novel anti-fibrosis nanomedicine. Previous studies have reported the potential of LY294002 (LY) as a PI3K/Akt inhibitor that suppresses the HSC activation and fibrosis development; however, its poor water solubility impedes further investigation. Moreover, the proliferation of HSC, severe oxidative stress and inflammatory conditions could be undermined by oridonin (ORD) treatment. Herein, we developed an HA-ORD/LY-Lips nanocomplex, where LY294002 was encapsulated into liposomes to prepare LY-Lips while ORD was conjugated with a hyaluronic acid (HA) polymer acting as a prodrug HA-ORD. The complex exerts great potential in improving the liver-targeted drug release. We adopted a series of in vitro and in vivo evaluations which demonstrate that HA-ORD/LY-Lips can significantly avert activation of hepatic stellate cells via scavenging reactive oxygen species and suppressing an inflammatory response. Our work implements a proof of concept strategy for fibrosis treatment based on the dual antioxidative and anti-inflammatory mechanisms, which may be applicable to treat liver fibrosis associated with a dysregulated inflammatory microenvironment.

Mechanotransduction in fibrosis: Mechanisms and treatment targets

To perceive and integrate the environmental cues, cells and tissues sense and interpret various physical forces like shear, tensile, and compression stress. Mechanotransduction involves the sensing and translation of mechanical forces into biochemical and mechanical signals to guide cell fate and achieve tissue homeostasis. Disruption of this mechanical homeostasis by tissue injury elicits multiple cellular responses leading to pathological matrix deposition and tissue stiffening, and consequent evolution toward pro-inflammatory/pro-fibrotic phenotypes, leading to tissue/organ fibrosis. This review focuses on the molecular mechanisms linking mechanotransduction to fibrosis and uncovers the potential therapeutic targets to halt or resolve fibrosis.

Targeting the Wnt/β-Catenin Signaling Pathway as a Potential Therapeutic Strategy in Renal Tubulointerstitial Fibrosis

The Wnt/β-catenin signaling pathway plays important roles in embryonic development and tissue homeostasis. Wnt signaling is induced, and β-catenin is activated, associated with the development and progression of renal fibrosis. Wnt/β-catenin controls the expression of various downstream mediators such as snail1, twist, matrix metalloproteinase-7, plasminogen activator inhibitor-1, transient receptor potential canonical 6, and renin-angiotensin system components in epithelial cells, fibroblast, and macrophages. In addition, Wnt/β-catenin is usually intertwined with other signaling pathways to promote renal interstitial fibrosis. Actually, given the crucial of Wnt/β-catenin signaling in renal fibrogenesis, blocking this signaling may benefit renal interstitial fibrosis. There are several antagonists of Wnt signaling that negatively control Wnt activation, and these include soluble Fzd-related proteins, the family of Dickkopf 1 proteins, Klotho and Wnt inhibitory factor-1. Furthermore, numerous emerging small-molecule β-catenin inhibitors cannot be ignored to prevent and treat renal fibrosis. Moreover, we reviewed the knowledge focusing on anti-fibrotic effects of natural products commonly used in kidney disease by inhibiting the Wnt/β-catenin signaling pathway. Therefore, in this review, we summarize recent advances in the regulation, downstream targets, role, and mechanisms of Wnt/β-catenin signaling in renal fibrosis pathogenesis. We also discuss the therapeutic potential of targeting this pathway to treat renal fibrosis; this may shed new insights into effective treatment strategies to prevent and treat renal fibrosis.