Coordination-driven assembly of catechol-modified chitosan for the kidney-specific delivery of salvianolic acid B to treat renal fibrosis

Shen Shuai II recipe improves renal hypoxia to attenuate renal injury in 5/6 renal ablation/infarction rats and effect evaluation using blood oxygenation level-dependent functional magnetic resonance imaging

Background: Renal hypoxia plays a key role in the progression of chronic kidney disease (CKD). Shen Shuai II Recipe (SSR) has shown good results in the treatment of CKD as a common herbal formula. This study aimed to explore the effect of SSR on renal hypoxia and injury in CKD rats. Methods: Twenty-five Wistar rats underwent 5/6 renal ablation/infarction (A/I) surgery were randomly divided into three groups: 5/6 (A/I), 5/6 (A/I) + losartan (LOS), and 5/6 (A/I) + SSR groups. Another eight normal rats were used as the Sham group. After 8-week corresponding interventions, blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) was performed to evaluate renal oxygenation in all rats, and biochemical indicators were used to measure kidney and liver function, hemoglobin, and proteinuria. The expression of fibrosis and hypoxia-related proteins was analyzed using immunoblotting examination. Results: Renal oxygenation, evaluated by BOLD-fMRI as cortical and medullary T2* values (COT2* and MET2*), was decreased in 5/6 (A/I) rats, but increased after SSR treatment. SSR also downregulated the expression of hypoxia-inducible factor-1α (HIF-1α) in 5/6 (A/I) kidneys. With the improvement of renal hypoxia, renal function and fibrosis were improved in 5/6 (A/I) rats, accompanied by reduced proteinuria. Furthermore, the COT2* and MET2* were significantly positively correlated with the levels of creatinine clearance rate (Ccr) and hemoglobin, but negatively associated with the levels of serum creatinine (SCr), blood urea nitrogen (BUN), serum cystatin C (CysC), serum uric acid (UA), 24-h urinary protein (24-h Upr), and urinary albumin:creatinine ratio (UACR). Conclusion: The degree of renal oxygenation reduction is correlated with the severity of renal injury in CKD. SSR can improve renal hypoxia to attenuate renal injury in 5/6 (A/I) rats of CKD.

A quantitative review of nanotechnology-based therapeutics for kidney diseases

Kidney-specific nanocarriers offer a targeted approach to enhance therapeutic efficacy and reduce off-target effects in renal treatments. The nanocarriers can achieve organ or cell specificity via passive targeting and active targeting mechanisms. Passive targeting capitalizes on the unique physiological traits of the kidney, with factors like particle size, charge, shape, and material properties enhancing organ specificity. Active targeting, on the other hand, achieves renal specificity through ligand-receptor interactions, modifying nanocarriers with molecules, peptides, or antibodies for receptor-mediated delivery. Nanotechnology-enabled therapy targets diseased kidney tissue by modulating podocytes and immune cells to reduce inflammation and enhance tissue repair, or by inhibiting myofibroblast differentiation to mitigate renal fibrosis. This review summarizes the current reports of the drug delivery systems that have been tested in vivo, identifies the nanocarriers that may preferentially accumulate in the kidney, and quantitatively compares the efficacy of various cargo-carrier combinations to outline optimal strategies and future research directions. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Delivery of sorafenib by myofibroblast-targeted nanoparticles for the treatment of renal fibrosis

Fibrosis is an excessive accumulation of the extracellular matrix within solid organs in response to injury and a common pathway that leads functional failure. No clinically approved agent is available to reverse or even prevent this process. Herein, we report a nanotechnology-based approach that utilizes a drug carrier to deliver a therapeutic cargo specifically to fibrotic kidneys, thereby improving the antifibrotic effect of the drug and reducing systemic toxicity. We first adopted in vitro-in vivo combinatorial phage display technology to identify peptide ligands that target myofibroblasts in mouse unilateral ureteral obstruction (UUO)-induced fibrotic kidneys. We then engineered lipid-coated poly(lactic-co-glycolic acid) nanoparticles (NPs) with fibrotic kidney-homing peptides on the surface and sorafenib, a potent antineoplastic multikinase inhibitor, encapsulated in the core. Sorafenib loaded in the myofibroblast-targeted NPs significantly reduced the infiltration of α-smooth muscle actin-expressing myofibroblasts and deposition of collagen I in UUO-treated kidneys and enhanced renal plasma flow measured by Technetium-99m mercaptoacetyltriglycine scintigraphy. This study demonstrates the therapeutic potential of the newly identified peptide fragments as anchors to target myofibroblasts and represents a strategic advance for selective delivery of sorafenib to treat renal fibrosis. SIGNIFICANCE STATEMENT: Renal fibrosis is a pathological feature accounting for the majority of issues in chronic kidney disease (CKD), which may progress to end-stage renal disease (ESRD). This manuscript describes a myofibroblast-targeting drug delivery system modified with phage-displayed fibrotic kidney-homing peptides. By loading the myofibroblast-targeting nanoparticles (NPs) with sorafenib, a multikinase inhibitor, the NPs could suppress collagen synthesis in cultured human myofibroblasts. When given intravenously to mice with UUO-induced renal fibrosis, sorafenib loaded in myofibroblast-targeting NPs significantly ameliorated renal fibrosis. This approach provides an efficient therapeutic option to renal fibrosis. The myofibroblast-targeting peptide ligands and nanoscale drug carriers may be translated into clinical application in the future.

Shen Shuai Ⅱ Recipe attenuates renal fibrosis in chronic kidney disease by improving hypoxia-induced the imbalance of mitochondrial dynamics via PGC-1α activation

BACKGROUND

Shen Shuai Ⅱ Recipe (SSR) is an effective Chinese herbal formula for the treatment of patients with chronic kidney disease (CKD) in the clinic and significantly improves 5/6 ablation and infarction (A/I) surgery-induced renal interstitial fibrosis (RIF) and intrarenal hypoxia in rats. However, the underlying molecular mechanisms need further elucidation.

PURPOSE

This study aims to investigate the renoprotective mechanisms of SSR in vivo and in vitro.

METHODS

CKD model was induced in rats with 5/6 (A/I) surgery. 4 weeks later, rats were treated with vehicle or SSR or Fenofibrate by daily gavage. In vitro, HK2 cells exposed to hypoxia (1% O2) were treated with SSR in the presence or absence of 100 μM MitoTEMPO or 10 μM Mitochondrial Fusion Promoter M1. The effects of SSR on RIF, mitochondrial dynamics, oxidative metabolism, and mitochondrial ROS (mtROS) were determined by immunoblotting, colorimetric, and fluorometric assays according to the experimental protocols. Furthermore, to explore the mechanisms of SSR against RIF, HK2 cells of PGC-1α or MFN2 knockdown under hypoxic stimulation were treated with 400 μg/ml of SSR and (or) 1 μM of ZLN005.

RESULTS

The results showed that treatment with SSR significantly improved mitochondrial morphology and function, up-regulated the expression of PGC-1α protein, and inhibited the production of mtROS in 5/6 (A/I) kidneys and hypoxia-treated HK2 cells, which may be closely correlated with its anti-RIF effect. In addition, compared to wild-type HK2 cells, the roles of SSR in improving mitochondrial dynamics and energy metabolism were greatly diminished in HK2 cells of PGC-1α knockdown under hypoxic exposure. More importantly, compared to ZLN005 or SSR combined with ZLN005 treatment, MFN2-deficient HK2 cells exhibited the increased protein levels of FN, α-SMA, TGF-β1 and cleaved IL-1β in response to hypoxic stimulation.

CONCLUSION

SSR exerted the renoprotective effects by improving mitochondrial dynamics under hypoxic condition via PGC-1α activation.

Cross-Linked Supramolecular Polymer Networks Constructed by Pillar[5]arene-Based Host–Guest Recognition and Coordination/Oxidation of Catechol

In this work, two cross-linked supramolecular polymers are prepared by pillar[5]arene-based molecular recognition and coordination/oxidation of catechol. In addition, two supramolecular glues are obtained at high concentrations of the cross-linked...

Tongluo Yishen Decoction Ameliorates Renal Fibrosis via Regulating Mitochondrial Dysfunction Induced by Oxidative Stress in Unilateral Ureteral Obstruction Rats

Tongluo Yishen (TLYS) decoction is an herb that is extensively applied for the treatment of chronic kidney disease (CKD) in traditional Chinese medicine. In this study, 37 different dominant chemical constituents of TLYS were identified. Rats with unilateral ureteral obstruction (UUO) were used as animal models, and TLYS decoction was administered orally for 14 days. TLYS decoction reduced the levels of renal function indicators, serum creatinine levels and blood urea nitrogen levels and alleviated renal pathological changes. Gene Ontology (GO) and KEGG pathway analyses of RNA sequencing data showed that TLYS decoction had significant effects on biological processes, cellular components and molecular functions in UUO rats and that the phagosome (a membrane source in the early stages of autophagy), lysosome (an important component of autolysosome), and oxidation pathways (which contribute to mitochondrial function) might be related to the antifibrotic effects of TLYS decoction. Moreover, we found significant mitochondrial function impairment, including a decreased mitochondrial membrane potential (MMP) and an imbalance in mitochondrial dynamics, excessive oxidative stress, and activation of Pink1/Parkin-mediated mitophagy in UUO rats. Treatment with TLYS decoction significantly increased the MMP, normalized mitochondrial dynamics and ameliorated renal injury. Moreover, TLYS alleviated the mitophagy clearance deficiency. In conclusion, our study showed that TLYS decoction can ameliorate mitochondrial dynamics by reducing oxidative stress and regulating mitophagy, thereby relieving renal injury, protecting renal function, and reducing renal fibrosis. This study provides support for the application of and further research on TLYS decoction.

Therapeutic and delivery strategies of phytoconstituents for renal fibrosis

Chronic kidney disease (CKD) is one of the most common diseases endangering human health and life. By 2030, 14 per 100,000 people may die from CKD. Renal fibrosis (RF) is an important intermediate link and the final pathological change during CKD progression to the terminal stage. Therefore, identifying safe and effective treatment methods for RF has become an important goal. In 2018, the World Health Organization introduced traditional Chinese medicine into its effective global medical program. Various phytoconstituents that affect the RF process have been extracted from different plants. Here, we review the potential therapeutic capabilities of active phytoconstituents in RF treatment and discuss how phytoconstituents can be structurally modified or combined with other ingredients to enhance efficiency and reduce toxicity. We also summarize phytoconstituent delivery strategies to overcome renal barriers and improve bioavailability and targeting.

Natural Glycan Derived Biomaterials for Inflammation Targeted Drug Delivery

Inflammation is closely related to a variety of fatal or chronic diseases. Hence, targeting inflammation provides an alternative approach to improve the therapeutic outcome of diseases such as solid tumors, neurological diseases, and metabolic diseases. Polysaccharides are natural components with immune regulation, anti-virus, anti-cancer, anti-inflammation, and anti-oxidation activities. Herein, this review highlights recent progress in the polysaccharide-based drug delivery systems for achieving inflammation targeting and its related disease treatment. Moreover, the chemical modification and the construction of polysaccharide materials for drug delivery are discussed in detail.

Exploring the mechanisms underlying the therapeutic effect of Salvia miltiorrhiza in diabetic nephropathy using network pharmacology and molecular docking

The mechanisms underlying the therapeutic effect of Salvia miltiorrhiza (SM) on diabetic nephropathy (DN) were examined using a systematic network pharmacology approach and molecular docking. The Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was used to screen active ingredients of SM. Targets were obtained using the SwissTargetPrediction and TCMSP databases. Proteins related to DN were retrieved from the GeneCards and DisGeNET databases. A protein–protein interaction (PPI) network was constructed using common SM/DN targets in the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database. The Metascape platform was used for Gene Ontology (GO) function analysis, and the Cytoscape plug-in ClueGO was used for Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Molecular docking was performed using iGEMDOCK and AutoDock Vina software. Pymol and LigPlos were used for network mapping. Sixty-six active ingredients and 189 targets of SM were found. Sixty-four targets overlapped with DN-related proteins. The PPI network revealed that AKT serine/threonine kinase 1 (AKT1), VEGFA, interleukin 6 (IL6), TNF, mitogen-activated protein kinase 1 (MAPK1), tumor protein p53 (TP53), epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3), mitogen-activated protein kinase 14 (MAPK14), and JUN were the ten most relevant targets. GO and KEGG analyses revealed that the common targets of DN and SM were mainly involved in advanced glycation end-products, oxidative stress, inflammatory response, and immune regulation. Molecular docking revealed that potential DN-related targets, including tumor necrosis factor (TNF), NOS2, and AKT1, more stably bound with salvianolic acid B than with tanshinone IIA. In conclusion, the present study revealed the active components and potential molecular therapeutic mechanisms of SM in DN and provides a reference for the wide application of SM in clinically managing DN.

Targeted Drug Delivery Systems for Kidney Diseases

Kidney diseases have gradually become a global health burden. Along with the development of nanotechnology, many hybrids or nanomaterials have been utilized to promote treatment efficiency with negligible side effects. These therapeutic agents have been successfully applied in many fields. In particular, some efforts have also been made to ameliorate the treatment of kidney diseases through targeted delivery nanomaterials. Though most of the delivery systems have not yet been transmitted into clinical use or even still at an early stage, they have shown great potential in carrying immunosuppressants like tacrolimus and triptolide, antioxidants, or siRNAs. Excitingly, some of them have achieved significant treatment effectiveness and reduced systemic side effect in kidney disease animal models. Here, we have reviewed the recent advances and presented nanotherapeutic devices designed for kidney targeted delivery.

Salvianolic Acid B Protects Against Fatty Acid-Induced Renal Tubular Injury via Inhibition of Endoplasmic Reticulum Stress

Background/Aims: Obesity-related kidney disease is associated with elevated levels of saturated free fatty acids (SFA). SFA lipotoxicity in tubular cells contributes to significant cellular apoptosis and injury. Salvianolic acid B (SalB) is the most abundant bioactive molecule from Radix Salviae Miltiorrhizae. In this study, we investigated the effect of SalB on SFA-induced renal tubular injury and endoplasmic reticulum (ER) stress, in vivo and in vitro. Methods: C57BL/6 mice were assigned to five groups: a control group with normal diet (Nor), high-fat diet group (HFD), and HFD with three different SalB treatment doses, low (SalBL; 3 mg/kg), medium (SalBM; 6.25 mg/kg), and high (SalBH; 12.5 mg/kg) doses. SalB was intraperitoneally injected daily for 4 weeks after 8 weeks of HFD. After 12 weeks, mice were sacrificed and kidneys and sera were collected. Apoptosis and ER stress were induced in human proximal tubule epitelial (HK2) cells by palmitic acid (PA, 0.6 mM), tunicamycin (TM, 1 μg/ml), or thapsigargin (TG, 200 nM) in vitro. Results: C57BL/6 mice fed a high-fat diet (HFD) for 12 weeks exhibited increased apoptosis (Bax and cleaved caspase-3) and ER stress (BIP, P-eIF2α, ATF4, CHOP, ATF6, IRE1α, and XBP1s) markers expression in the kidney, compared with control mice, which were remarkably suppressed by SalB treatment. In vitro studies showed that PA (0.6 mM) induced apoptosis and ER stress in cultured HK2 cells. SalB treatment attenuated all the adverse effects of PA. However, SalB failed to inhibit TM or TG-induced ER stress in HK2 cells. Conclusion: The study indicated that SalB may play an important role in obesity-related kidney injury via mediating SFA-induced ER stress.

Pharmacological Effects of Salvianolic Acid B Against Oxidative Damage

Salvianolic acid B (Sal B) is one of the main active ingredients of Salvia miltiorrhiza, with strong antioxidant effects. Recent findings have shown that Sal B has anti-inflammatory, anti-apoptotic, anti-fibrotic effects and can promote stem cell proliferation and differentiation, and has a beneficial effect on cardiovascular and cerebrovascular diseases, aging, and liver fibrosis. Reactive oxygen species (ROS) include oxygen free radicals and oxygen-containing non-free radicals. ROS can regulate cell proliferation, survival, death and differentiation to regulate inflammation, and immunity, while Sal B can scavenge oxygen free radicals by providing hydrogen atoms and reduce the production of oxygen free radicals and oxygen-containing non-radicals by regulating the expression of antioxidant enzymes. The many pharmacological effects of Sal B may be closely related to its elimination and inhibition of ROS generation, and Nuclear factor E2-related factor 2/Kelch-like ECH-related protein 1 may be the core link in its regulation of the expression of antioxidant enzyme to exert its antioxidant effect. What is confusing and interesting is that Sal B exhibits the opposite mechanisms in tumors. To clarify the specific target of Sal B and the correlation between its regulation of oxidative stress and energy metabolism homeostasis will help to further understand its role in different pathological conditions, and provide a scientific basis for its further clinical application and new drug development. Although Sal B has broad prospects in clinical application due to its extensive pharmacological effects, the low bioavailability is a serious obstacle to further improving its efficacy in vivo and promoting clinical application. Therefore, how to improve the availability of Sal B in vivo requires the joint efforts of many interdisciplinary subjects.

Chemical characterisation and quantification of the major constituents in the Chinese herbal formula Jian-Pi-Yi-Shen pill by UPLC-Q-TOF-MS/MS and HPLC-QQQ-MS/MS

INTRODUCTION

Jian-Pi-Yi-Shen pill (JPYSP) is a Chinese medicine formula developed for the treatment of anaemic patients with chronic kidney disease (CKD).

OBJECTIVE

To investigate the chemical profile of JPYSP in the treatment of renal anaemia.

METHODS

A method coupling ultra-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) was established to characterise the chemical constituents present in JPYSP. Subsequently, a high-performance liquid chromatography method coupled with triple-quadrupole tandem mass spectrometry (HPLC-QQQ-MS/MS) was developed to quantify the major constituents from the identified compounds related to the treatment of CKD and anaemia.

RESULTS

A total of 71 compounds were tentatively identified from JPYSP, including saponins, flavonoids, sesquiterpenoids, coumarins, phenylpropanoids, anthranones, anthraquinones, tannins, phenolic acids and others. Amongst them, 12 compounds (i.e. astragaloside IV, calycosin, calycosin 7-O-glucoside, salvianolic acid A, rosmarinic acid, rhein, liquiritin, formononetin, atractylenolide I, dioscin, tanshinone IIA, and acteoside) were further quantified simultaneously by HPLC-QQQ-MS/MS.

CONCLUSION

The newly developed approach is suitable for the chemical profiling analysis and quality control of JPYSP, and could lead to additional pharmacodynamic studies involving the components of JPYSP.

Possible applications of salvianolic acid B against different cancers

Cancer is the second death causing disease worldwide after cardiovascular abnormalities. The difficulty in treating tumor cells with more precise targeted interventions and recurrence of cancer after treatment may pose great difficulty in developing sustainable therapeutic regimens. These limitations have prompted the need to explore several compounds with ability to cease tumor growth while at the same time induce apoptosis of tumor cells. Several studies have emphasized the use of natural compounds as antitumor agents due to their high efficacy against cancer cells and low toxicity in normal cells. Salvianolic acid B (SAB), a naturally occurring phenolic compound extracted from the radix of Chinese herb Salvia miltiorrhiza can induce apoptosis in different types of tumor cells. It can be used to treat cardiovascular and neurodegenerative disorders, hepatic fibrosis, and cancers. Several studies have shown that SAB can mitigate tumorigenesis by modulating MAPK, PI3K/AKT, and NF-ĸB signaling pathways. It also sensitizes the tumor cells to different anti-cancer agents by reversing the multi-drug resistance mechanisms found in tumor cells. This review summarizes the studies showing antitumor potential of SAB in different types of cancer cell lines, animal models and highlights the possible mechanisms through which SAB can induce apoptosis, inhibit growth and metastasis in tumor cells. Moreover, the possible role of nano-technological approaches to induce targeted delivery of SAB to eradicate tumor cells has been also discussed.

Salvianolic acid B attenuates epithelial-mesenchymal transition in renal fibrosis rats through activating Sirt1-mediated autophagy

Renal fibrosis is a kind of progressive kidney disease leading to end-stage renal damage. Epithelial-mesenchymal transition (EMT) is one of the crucial features of renal fibrosis. Salvianolic acid B (SalB), isolated from traditional Chinese medicine Radix Salviae miltiorrhizae, has been proved to be suitable for renal protection. The aims of this study are to investigate the pharmacological effects of SalB on renal fibrosis and explore the underlying mechanisms. In vivo, our study showed that SalB could improve kidney dysfunction and reduce the expression of EMT-related proteins, including fibronectin (FN), α-smooth muscle actin (α-SMA) and transforming growth factor-β (TGF-β). In addition, SalB activated autophagy and up-regulated the expression of Sirt1. In vitro, our study showed that SalB reversed EMT in TGF-β1-induced human kidney proximal tubular epithelial cells (HK-2 cells). Further mechanism studies showed that the inhibition of Sirt1 and autophagy could reverse the protective effect of SalB on the EMT process in TGF-β1-induced HK-2 cells. Taken together, this study demonstrated that SalB attenuates EMT in the process of renal fibrosis through activating Sirt1-mediated autophagy, and Sirt1 could be a key target for treatment of renal fibrosis.

Chemical and pharmacological research on the polyphenol acids isolated from Danshen: A review of salvianolic acids

Danshen, the dried root of Salvia miltiorrhiza Bge, is a common medicinal herb in Traditional Chinese Medicine, which has been used for the treatment of a number of diseases for thousands of years. More than 2000 years ago, the Chinese early pharmacy monograph "Shennong Materia Medica" recorded that Danshen could be used for the treatment of gastrointestinal diseases, cardiovascular diseases, certain gynecological diseases, etc. Since then, Danshen has been widely used clinically in many different prescriptions for many different diseases, especially for the treatment of cardiovascular diseases. Nowadays, many pharmacological studies about the water-soluble components from Danshen have been reported, especially salvianolic acids. It turned out that salvianolic acids showed strong anti-lipid peroxidation and anti-thrombic activities, and among them, SalAA and SalAB were the most potent. This review focused on the achievements in research of salvianolic acids regarding their bioactivities and pharmacological effects. These studies not only shed light on the water-soluble active components of Danshen and their mechanisms at the molecular level, but also provided theoretical information for the development of new medicines from Danshen for the treatment of cardiovascular and cerebrovascular diseases, inflammatory diseases, metabolic diseases, etc.

Design and optimization strategies for the development of new drugs that treat chronic kidney disease

Introduction: Chronic kidney disease (CKD) is characterized by increased risks of progression to end-stage kidney disease requiring dialysis and cardiovascular mortality, predicted to be among the five top causes of death by 2040. Only the design and optimization of novel strategies to develop new drugs to treat CKD will contain this trend. Current therapy for CKD includes nonspecific therapy targeting proteinuria and/or hypertension and cause-specific therapies for diabetic kidney disease, autosomal dominant polycystic kidney disease, glomerulonephritides, Fabry nephropathy, hemolytic uremic syndrome and others.Areas covered: Herein, the authors review the literature on new drugs under development for CKD as well as novel design and development strategies.Expert opinion: New therapies for CKD have become a healthcare priority. Emerging therapies undergoing clinical trials are testing expanded renin-angiotensin system blockade with double angiotensin receptor/endothelin receptor blockers, SGLT2 inhibition, and targeting inflammation, the immune response, fibrosis and the Nrf2 transcription factor. Emerging therapeutic targets include cell senescence, complement activation, Klotho expression preservation and microbiota. Novel approaches include novel model systems that can be personalized (e.g. organoids), unbiased systems biology-based identification of new therapeutic targets, drug databases that speed up drug identification and repurposing, nanomedicines that improve drug delivery and RNA targeting to expand the number of targetable proteins.

Therapeutic potential of NaoXinTong Capsule on the developed diabetic nephropathy in db/db mice

The current treatment for diabetic nephropathy (DN) is still limited. NaoXinTong Capsule (NXT) is a Chinese Medicine prescribed to patients with cardiovascular disease. It can also ameliorate metabolic syndromes in patients indicating its anti-diabetic properties. Herein we report the therapeutic effects of NXT on the developed DN. The db/db diabetic mice at ˜12 weeks old, the age with DN at middle/advanced stages, were treated with NXT for 12 weeks. We found NXT treatment reduced diabetes-induced hyperglycemia and dyslipidemia, thereby substantially reduced DN progress. In the kidney, NXT reduced mesangial matrix expansion and glomerulosclerosis by inhibiting extracellular matrix accumulation through activation of matrix metalloproteinase 2/9 and inactivating transforming growth factor β1 expression. NXT reduced podocyte injury by reducing renal inflammation and expression of adhesion molecules. Mechanically, NXT potently activated AMPKα in multiple tissues thereby enhancing energy metabolism. In the liver, NXT increased glucokinase expression and insulin sensitivity by increasing insulin receptor substrate 1/2 and protein kinase B (AKT) 1/2 expression/phosphorylation. In skeletal muscle, NXT activated expression of glucose transporter type 4, AKT, glycogen synthase and peroxisome proliferator activated receptor α/γ. In adipose tissue, NXT reduced fatty acid synthase while activating hormone-sensitive lipase expression. Taken together, our study demonstrates that NXT reduced progress of the developed DN by ameliorating glucose, lipid and energy metabolism, maintaining renal structural and functional integrity. Our study also indicates the potential application of NXT for DN treatment in clinics.

Flow Behavior Prior to Crosslinking: The Need for Precursor Rheology for Placement of Hydrogels in Medical Applications and for 3D Bioprinting

Hydrogels - water swollen cross-linked networks - have demonstrated considerable promise in tissue engineering and regenerative medicine applications. However, ambiguity over which rheological properties are needed to characterize these gels before crosslinking still exists. Most hydrogel research focuses on the performance of the hydrogel construct after implantation, but for clinical practice, and for related applications such as bioinks for 3D bioprinting, the behavior of the pre-gelled state is also critical. Therefore, the goal of this review is to emphasize the need for better rheological characterization of hydrogel precursor formulations, and standardized testing for surgical placement or 3D bioprinting. In particular, we consider engineering paste or putty precursor solutions (i.e., suspensions with a yield stress), and distinguish between these differences to ease the path to clinical translation. The connection between rheology and surgical application as well as how the use of paste and putty nomenclature can help to qualitatively identify material properties are explained. Quantitative rheological properties for defining materials as either pastes or putties are proposed to enable easier adoption to current methods. Specifically, the three-parameter Herschel-Bulkley model is proposed as a suitable model to correlate experimental data and provide a basis for meaningful comparison between different materials. This model combines a yield stress, the critical parameter distinguishing solutions from pastes (100-2000 Pa) and from putties (>2000 Pa), with power law fluid behavior once the yield stress is exceeded. Overall, successful implementation of paste or putty handling properties to the hydrogel precursor may minimize the surgeon-technology learning time and ultimately ease incorporation into current practice. Furthermore, improved understanding and reporting of rheological properties will lead to better theoretical explanations of how materials affect rheological performances, to better predict and design the next generation of biomaterials.

Salvianolic Acids: Potential Source of Natural Drugs for the Treatment of Fibrosis Disease and Cancer

Salvianolic acids, the most effective and abundant compounds extracted from Salvia miltiorrhiza (Danshen), are well known for its good anti-oxidative activity. Danshen has been extensively used as a traditional medicine to treat cardiovascular-related diseases in China and other Asian countries for hundreds of years. Recently, more and more studies have demonstrated that salvianolic acids also have a good effect on the alleviation of fibrosis disease and the treatment of cancer. In vivo and in vitro experiments have demonstrated that salvianolic acids can modulate signal transduction within fibroblasts and cancer cells. It is discovered that the cancer treatment of salvianolic acids is not only because salvianolic acids promote the apoptosis of cancer cells, but also due to the inhibition of cancer-associated epithelial-mesenchymal transition processes. In this article, we review a variety of studies focusing on the comprehensive roles of salvianolic acids in the treatment of fibrosis disease and cancer. These perspectives on the therapeutic potential of salvianolic acids highlight the importance of these compounds, which could be the novel and attractive drugs for fibrosis disease and cancer.

Remarkable Amplification of Polyethylenimine-Mediated Gene Delivery Using Cationic Poly(phenylene ethynylene)s as Photosensitizers

Conjugated polymers can serve as good photosensitizers in biomedical applications. However, it remains unknown whether they are phototoxic to the supercoiled structure of DNA in improving gene delivery by the photochemical internalization (PCI) strategy, which complicates the application of conjugated polymers in gene delivery. In this work, we introduced a trace amount of cationic poly(phenylene ethynylene)s (cPPEs) into the polymeric shell of branched polyethylenimine (BPEI)/DNA complexes, studied the photosensitization of singlet oxygen by cPPEs, and confirmed that the supercoiled DNA is undamaged by the singlet oxygen generated by the photoexcitation of cPPEs. By taking advantage of the cPPE-mediated PCI effect, we report that the addition of the trace amount of cPPEs to the outer shell of the BPEI/DNA polyplexes could greatly amplify the transfection of gene green fluorescent protein on tumor cells with the efficiency from 14 to 86% without decreasing the cell viabilities, well solving the problem with a poor transfection capability of BPEI under low DNA-loading conditions. Our strategy to employ conjugated polymers as photosensitizing agents in gene delivery systems is simple, safe, efficient, and promising for broad applications in gene delivery areas.