Light-triggered NO-releasing nanoparticles for treating mice with liver fibrosis

Targeted delivery of polymeric NO-donor micelles to hepatic stellate cells for restoration of liver function and inhibition of hepatic fibrosis

Liver fibrosis is a prevalent liver disease associated with significant morbidity, and the activation of hepatic stellate cells (HSCs) serves as the primary causative factor driving the progression of liver fibrosis. However, capillarization of liver sinusoidal endothelial cells (LSECs) induced by hepatic fibrosis can reduce nitric oxide (NO) production and bioavailability, which consequently loses the ability to retain HSCs dormant, leading to amplified HSCs activation. Herein, an elaborate micelle (VN-M@BN) loaded with benazepril (BN) was constructed by self-assembly of polymeric NO donor, aiming for the controlled release of NO in liver fibrosis lesions thereby impeding the progression of liver fibrosis. VN-M@BN with the vitamin A (VA) ligand modification was designed to target HSCs for efficient liver fibrosis inhibition. Controlled NO release significantly downregulated α-smooth muscle actin (α-SMA) and induced apoptosis of activated HSCs, thus enhancing the inhibition effects of BN towards HSCs. Furthermore, the in suit antifibrotic treatment results confirmed that VN-M@BN possessed good circulatory stability and targetability to liver fibrotic tissues, thereby effectively ameliorating the collagen deposition and fibrosis process in damaged liver tissues. The NO-based targeted nanodrug system enabled precise delivery of therapeutic drugs to activated HSCs, thereby synergizing the efficacy in treating liver fibrosis with minimal adverse effects.

Nano-encapsulation of drugs to target hepatic stellate cells: Toward precision treatments of liver fibrosis

Liver fibrosis is characterized by excessive extracellular matrix (ECM) deposition triggered by hepatic stellate cells (HSCs). As central players in fibrosis progression, HSCs are the most important therapeutic targets for antifibrotic therapy. However, owing to the limitations of systemic drug administration, there is still no suitable and effective clinical treatment. In recent years, nanosystems have demonstrated expansive therapeutic potential and evolved into a clinical modality. In liver fibrosis, nanosystems have undergone a paradigm shift from targeting the whole liver to locally targeted modifying processes. Nanomedicine delivered to HSCs has significant potential in managing liver fibrosis, where optimal management would benefit from targeted delivery, personalized therapy based on the specific site of interest, and minor side effects. In this review, we present a brief overview of the role of HSCs in the pathogenesis of liver fibrosis, summarize the different types of nanocarriers and their specific delivery applications in liver fibrosis, and highlight the biological barriers associated with the use of nanosystems to target HSCs and approaches available to solve this issue. We further discuss in-depth all the molecular target receptors overexpressed during HSC activation in liver fibrosis and their corresponding ligands that have been used for drug or gene delivery targeting HSCs.

Dual-Targeting Macrophages and Hepatic Stellate Cells by Modified Albumin Nanoparticles for Liver Cirrhosis Treatment

Hepatic cirrhosis has become a global public health concern with high mortality and currently lacks effective clinical treatment methods. Activation of hepatic stellate cells (HSCs) and the large number of macrophages infiltrating into the liver play a critical role in the development of liver cirrhosis. This study developed a novel modified nanoparticle system (SRF-CS-PSA NPs) in which Sorafenib (SRF) was encapsulated by palmitic acid-modified albumin (PSA) and further modified with chondroitin sulfate (CS). These modifications enabled the SRF-CS-PSA NPs to effectively target hepatic stellate cells (HSCs) and macrophages. SRF-CS-PSA NPs showed uniform particle size distribution of approximately 120 nm and high loading efficiency of up to 99.5% and can be taken up by HSCs and macrophages via CD44 and SR-A receptors, respectively. In a mouse model of liver cirrhosis, SRF-CS-PSA NPs demonstrated superior targeting and inhibition of HSCs and macrophages, effectively reversing the process of liver cirrhosis. Overall, our study demonstrates the potential of SRF-CS-PSA NPs as a targeted therapy for liver cirrhosis, with promising clinical applications.

Controlled siRNA Release of Nanopolyplex for Effective Targeted Anticancer Therapy in Animal Model

Introduction

Spatiotemporally controlled release of siRNA for anti-tumor therapy poses significant challenges. Near-infrared (NIR) light, known for its exceptional tissue penetration and minimal tissue invasiveness, holds promise as a viable exogenous stimulus for inducing controlled siRNA release in vivo. However, the majority of light-responsive chemical bonds exhibit absorption wavelengths in the ultraviolet (UV) or short-wavelength visible light range.

Methods

To achieve NIR-controlled siRNA release, the study synthesized a UV-sensitive triblock copolymer cRGD-poly(ethylene glycol)-b-poly(aspartic acid ester-5-(2'-(dimethylamino)ethoxy)-2-nitrobenzyl alcohol)-b-polyphenylalanine, abbreviated as cRGD-PEG-PAsp(EDONB)-PPHE. This copolymer is composed of a cRGD-capped PEG block (cRGD-PEG), a poly(aspartate) block modified with cationic moieties through UV-cleavable 2-nitrobenzyl ester bonds [PAsp(EDONB)], and a hydrophobic polyphenylalanine block (PPHE). The cationic amphiphilic polymer cRGD-PEG-PAsp(EDONB)-PPHE can assemble with hydrophobic upconversion nanoparticles (UCNPs) to form a cationic micelle designated as T-UCNP, which subsequently complexes with siRNA to create the final nanopolyplex T-si/UCNP. siRNA-PLK1 was employed to prepare T-PLK1/UCNP nanopolyplex for anti-tumor therapy.

Results

T-PLK1/UCNP not only exhibited outstanding tumor cell targeting through cRGD modification but also achieved 980 nm NIR-controlled PLK1 gene silencing. This was achieved by utilizing the encapsulated UCNPs to convert NIR into UV light, facilitating the cleavage of 2-nitrobenzyl ester bonds. As a result, there was a significant suppression of tumor growth.

Conclusion

The UCNPs-encapsulated nanopolyplex T-si/UCNP, capable of co-delivering siRNA and UCNPs, enables precise NIR-controlled release of siRNA at the tumor site for cancer RNAi therapy. This nanopolyplex can enhance the controllability and safety of RNAi therapy for tumors, and it also holds the potential to serve as a platform for achieving controlled release and activation of other drugs, such as mRNA and DNA.

Liver fibrosis: pathological features, clinical treatment and application of therapeutic nanoagents

Liver fibrosis is a reversible damage-repair response, the pathological features of which mainly include damage to hepatocytes, sinusoid capillarization, hepatic stellate cells activation, excessive accumulation of extracellular matrix and inflammatory response. Although some treatments (including drugs and stem cell therapy) for these pathological features have been shown to be effective, more clinical trials are needed to confirm their effectiveness. In recent years, nanomaterials-based therapies have emerged as an innovative and promising alternative to traditional drugs, being explored for the treatment of liver fibrosis diseases. Natural nanomaterials (including extracellular vesicles) and synthetic nanomaterials (including inorganic nanomaterials and organic nanomaterials) are developed to facilitate drug targeting delivery and combination therapy. In this review, the pathological features of liver fibrosis and the current anti-fibrosis drugs in clinical trials are briefly introduced, followed by a detailed introduction of the therapeutic nanoagents for the precise delivery of anti-fibrosis drugs. Finally, the future development trend in this field is discussed.

The Combination of Sinusoidal Perfusion Enhancement and Apoptosis Inhibition by Riociguat Plus a Galactose-PEGylated Bilirubin Multiplexing Nanomedicine Ameliorates Liver Fibrosis Progression

Chronic liver injury and continuous wound healing lead to extracellular matrix (ECM) deposition and liver fibrosis. The elevated production of reactive oxygen species (ROS) in the liver leads to the apoptosis of hepatocytes and the activation of hepatic stellate cells (HSCs). In the current study, we describe a combination strategy of sinusoidal perfusion enhancement and apoptosis inhibition enabled by riociguat together with a tailor-designed galactose-PEGylated bilirubin nanomedicine (Sel@GBRNPs). Riociguat enhanced sinusoidal perfusion and decreased the associated ROS accumulation and inflammatory state of the fibrotic liver. Concurrently, hepatocyte-targeting galactose-PEGylated bilirubin scavenged excessive ROS and released encapsulated selonsertib. The released selonsertib inhibited apoptosis signal-regulating kinase 1 (ASK1) phosphorylation to alleviate apoptosis in hepatocytes. The combined effects on ROS and hepatocyte apoptosis attenuated the stimulation of HSC activation and ECM deposition in a mouse model of liver fibrosis. This work provides a novel strategy for liver fibrosis treatment based on sinusoidal perfusion enhancement and apoptosis inhibition.

Restoration of Sinusoid Fenestrae Followed by Targeted Nanoassembly Delivery of an Anti-Fibrotic Agent Improves Treatment Efficacy in Liver Fibrosis

During the onset of liver fibrosis, capillarized liver sinusoidal endothelial cells (LSECs) limit substance exchange between the blood and the Disse space, further accelerating hepatic stellate cell (HSCs) activation and fibrosis progression. Limited accessibility of therapeutics to the Disse space is often overlooked and remains a major bottleneck for HSCs-targeted therapy in liver fibrosis. Here, an integrated systemic strategy for liver fibrosis treatment is reported, utilizing pretreatment with the soluble guanylate cyclase stimulator, riociguat, followed by insulin growth factor 2 receptor-mediated targeted delivery of the anti-fibrosis agent, JQ1, via peptide-nanoparticles (IGNP-JQ1). The riociguat reversed the liver sinusoid capillarization to maintain a relatively normal LSECs porosity, thus facilitating the transport of IGNP-JQ1 through the liver sinusoid endothelium wall and enhancing the accumulation of IGNP-JQ1 in the Disse space. IGNP-JQ1 is then selectively taken up by activated HSCs, inhibiting their proliferation and decreasing collagen deposition in the liver. The combined strategy results in significant fibrosis resolution in carbon tetrachloride-induced fibrotic mice as well as methionine-choline-deficient-diet-induced nonalcoholic steatohepatitis (NASH) mice. The work highlights the key role of LSECs in therapeutics transport through the liver sinusoid. The strategy of restoring LSECs fenestrae by riociguat represents a promising approach for liver fibrosis treatment.

Insights on drug and gene delivery systems in liver fibrosis

Complications of the liver are amongst the world's worst diseases. Liver fibrosis is the first stage of liver problems, while cirrhosis is the last stage, which can lead to death. The creation of effective anti-fibrotic drug delivery methods appears critical due to the liver's metabolic capacity for drugs and the presence of insurmountable physiological impediments in the way of targeting. Recent breakthroughs in anti-fibrotic agents have substantially assisted in fibrosis; nevertheless, the working mechanism of anti-fibrotic medications is not fully understood, and there is a need to design delivery systems that are well-understood and can aid in cirrhosis. Nanotechnology-based delivery systems are regarded to be effective but they have not been adequately researched for liver delivery. As a result, the capability of nanoparticles in hepatic delivery was explored. Another approach is targeted drug delivery, which can considerably improve efficacy if delivery systems are designed to target hepatic stellate cells (HSCs). We have addressed numerous delivery strategies that target HSCs, which can eventually aid in fibrosis. Recently genetics have proved to be useful, and methods for delivering genetic material to the target place have also been investigated where different techniques are depicted. To summarize, this review paper sheds light on the most recent breakthroughs in drug and gene-based nano and targeted delivery systems that have lately shown useful for the treatment of liver fibrosis and cirrhosis.

Enhanced Solubility and Biological Activity of Dexibuprofen-Loaded Silica-Based Ternary Solid Dispersions

The current study was designed to formulate ternary solid dispersions (TSDs) of dexibuprofen (Dex) by solvent evaporation to augment the solubility and dissolution profile, in turn providing gastric protection and effective anti-inflammatory activity. Initially, nine formulations (S1 to S9) of binary solid dispersions (BSDs) were developed. Formulation S1 comprising a 1:1 weight ratio of Dex and Syloid 244FP^® was chosen as the optimum BSD formulation due to its better solubility profile. Afterward, 20 TSD formulations were developed using the optimum BSD. The formulation containing Syloid 244FP^® with 40% Gelucire 48/16^® (S18) and Poloxamer 188^® (S23) successfully enhanced the solubility by 28.23 and 38.02 times, respectively, in pH 6.8, while dissolution was increased by 1.99- and 2.01-fold during the first 5 min as compared to pure drug. The in vivo gastroprotective study in rats suggested that the average gastric lesion index was in the order of pure Dex (8.33 ± 2.02) > S1 (7 ± 1.32) > S18 (2.17 ± 1.61) > S23 (1.83 ± 1.04) > control (0). The in vivo anti-inflammatory study in rats revealed that the percentage inhibition of swelling was in the order of S23 (71.47 ± 2.16) > S18 (64.8 ± 3.79) > S1 (54.14 ± 6.78) > pure drug (18.43 ± 2.21) > control (1.18 ± 0.64) after 6 h. ELISA results further confirmed the anti-inflammatory potential of the developed formulation, where low levels of IL-6 and TNF alpha were reported for animals treated with S23. Therefore, S23 could be considered an effective formulation that not only enhanced the solubility and bioavailability but also reduced the gastric irritation of Dex.

Heavy metal toxicity in plants and the potential NO-releasing novel techniques as the impending mitigation alternatives

Environmental pollutants like heavy metals are toxic, persistent, and bioaccumulative in nature. Contamination of agricultural fields with heavy metals not only hampers the quality and yield of crops but also poses a serious threat to human health by entering the food chain. Plants generally cope with heavy metal stress by regulating their redox machinery. In this context, nitric oxide (NO) plays a potent role in combating heavy metal toxicity in plants. Studies have shown that the exogenous application of NO donors protects plants against the deleterious effects of heavy metals by enhancing their antioxidative defense system. Most of the studies have used sodium nitroprusside (SNP) as a NO donor for combating heavy metal stress despite the associated concerns related to cyanide release. Recently, NO-releasing nanoparticles have been tested for their efficacy in a few plants and other biomedical research applications suggesting their use as an alternative to chemical NO donors with the advantage of safe, slow and prolonged release of NO. This suggests that they may also serve as potential candidates in mitigating heavy metal stress in plants. Therefore, this review presents the role of NO, the application of chemical NO donors, potential advantages of NO-releasing nanoparticles, and other NO-release strategies in biomedical research that may be useful in mitigating heavy metal stress in plants.

Recent advances in upconversion nanoparticle-based nanocomposites for gas therapy

Gas therapy has attracted wide attention for the treatment of various diseases. However, a controlled gas release is highly important for biomedical applications. Upconversion nanoparticles (UCNPs) can precisely convert the long wavelength of light to ultraviolet/visible (UV/Vis) light in gas therapy for the controlled gas release owing to their unique upconversion luminescence (UCL) ability. In this review, we mainly summarized the recent progress of UCNP-based nanocomposites in gas therapy. The gases NO, O2, H2, H2S, SO2, and CO play an essential role in the physiological and pathological processes. The UCNP-based gas therapy holds great promise in cancer therapy, bacterial therapy, anti-inflammation, neuromodulation, and so on. Furthermore, the limitations and prospects of UCNP-based nanocomposites for gas therapy are also discussed.

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.

Multiplexing Nanodrug Ameliorates Liver Fibrosis via ROS Elimination and Inflammation Suppression

Liver fibrosis is the leading risk factor for hepatocellular carcinoma. Both oxidative stress and inflammation promote the progression of liver fibrosis, but existing therapeutic strategies tend to focus solely on one issue. Additionally, targeting of pathological microstructures is often neglected. Herein, an esterase-responsive carbon quantum dot-dexamethasone (CD-Dex) is developed for liver fibrosis therapy to simultaneously target pathological microstructures, scavenge reactive oxygen species (ROS), and suppress inflammation. Hepatocyte-targeting CD-Dex can efficiently eliminate the intrahepatic ROS, thereby inhibiting the activation of Kupffer cells, preventing further inflammation progression. Moreover, released dexamethasone (Dex) also suppresses inflammatory response by inhibiting the infiltration of inflammatory cells. Antifibrotic experiments demonstrate that CD-Dex significantly alleviates liver injury and collagen deposition, consequently preventing the progression of liver fibrosis. Taken together, these findings suggest that via ROS elimination and inflammation suppression, the newly developed multiplexing nanodrug exhibits great potential in liver fibrosis therapy.

Therapeutic and diagnostic targeting of fibrosis in metabolic, proliferative and viral disorders

Fibrosis is a common denominator in many pathologies and crucially affects disease progression, drug delivery efficiency and therapy outcome. We here summarize therapeutic and diagnostic strategies for fibrosis targeting in atherosclerosis and cardiac disease, cancer, diabetes, liver diseases and viral infections. We address various anti-fibrotic targets, ranging from cells and genes to metabolites and proteins, primarily focusing on fibrosis-promoting features that are conserved among the different diseases. We discuss how anti-fibrotic therapies have progressed over the years, and how nanomedicine formulations can potentiate anti-fibrotic treatment efficacy. From a diagnostic point of view, we discuss how medical imaging can be employed to facilitate the diagnosis, staging and treatment monitoring of fibrotic disorders. Altogether, this comprehensive overview serves as a basis for developing individualized and improved treatment strategies for patients suffering from fibrosis-associated pathologies.

Harnessing X-Ray Energy-Dependent Attenuation of Bismuth-Based Nanoprobes for Accurate Diagnosis of Liver Fibrosis

Timely detection of liver fibrosis by X-ray computed tomography (CT) can prevent its progression to fatal liver diseases. However, it remains quite challenging because conventional CT can only identify the difference in density instead of X-ray attenuation characteristics. Spectral CT can generate monochromatic imaging to specify X-ray attenuation characteristics of the scanned matter. Herein, an X-ray energy-dependent attenuation strategy originated from bismuth (Bi)-based nanoprobes (BiF3 @PDA@HA) is proposed for the accurate diagnosis of liver fibrosis. Bi element in BiF3 @PDA@HA can exhibit characteristic attenuation depending on different levels of X-ray energy via spectral CT, and that is challenging for conventional CT. In this study, selectively accumulating BiF3 @PDA@HA nanoprobes in the hepatic fibrosis areas can significantly elevate CT value for 40 Hounsfield units on 70 keV monochromatic images, successfully differentiating from healthy livers and achieving the diagnosis of liver fibrosis. Furthermore, the enhancement produced by the BiF3 @PDA@HA nanoprobes in vivo increases as the monochromatic energy decreases from 70 to 40 keV, optimizing the conspicuity of the diseased areas. As a proof of concept, the strategically designed nanoprobes with energy-dependent attenuation characteristics not only expand the scope of CT application, but also hold excellent potential for precise imaging-based disease diagnosis.

Advantages and challenges in nanomedicines for chronic liver diseases: A hepatologist's perspectives

Chronic liver diseases (CLD) are responsible for significant morbidity and mortality worldwide. CLD patients are at a high risk of developing progressive liver fibrosis, cirrhosis, hepatocellular carcinoma (HCC), and subsequent liver failure. To date, there is no specific and effective therapies exist for patients with various forms of CLD. The application of nanotechnology has emerged as a rapidly developing area of interest for the safe and target-specific delivery of poorly aqueous soluble hepatoprotective agents and nucleic acids (siRNA/miRNAs) in CLD. The nanoparticle combination improves bioavailability and plasma stability of drugs with poor aqueous solubility. However, the extent of successful functional delivery of nanoparticles into hepatocytes is often surprisingly low. High Kupffer cells interaction reduces the nanomedicine efficacy. During fibrosis, the extracellular matrix accumulation in the perisinusoidal space restricts nanoparticle delivery to hepatocytes. The availability and uptake of nanoparticles exposure to different cells in the liver microenvironment is as Kupffer cells > sinusoidal endothelial cells > HSCs > hepatocytes. The most widely used strategy to reduce nanoparticles and macrophages interaction is to coat the particle surface with polyethylene glycol. The cationic charged nanoparticles have increased hepatocyte delivery by increased cellular interaction by disrupting the endosomal system via their pH buffering capacity. The immune clearance and toxicity of nanoparticles are mainly unpredictable. Therefore, more elaborate knowledge on exact cellular uptake and intracellular accumulation, trafficking, and endosomal sorting of nanoparticle is the need of the hour to improve the rational carrier design.