Immunomodulatory poly(L-lactic acid) nanofibrous membranes promote diabetic wound healing by inhibiting inflammation, oxidation and bacterial infection.

Background: Given the significant impact on human health, it is imperative to develop novel treatment approaches for diabetic wounds, which are prevalent and serious complications of diabetes. The diabetic wound microenvironment has a high level of reactive oxygen species (ROS) and an imbalance between proinflammatory and anti-inflammatory cells/factors, which hamper the healing of chronic wounds. This study aimed to develop poly(L-lactic acid) (PLLA) nanofibrous membranes incorporating curcumin and silver nanoparticles (AgNPs), defined as PLLA/C/Ag, for diabetic wound healing. Methods: PLLA/C/Ag were fabricated via an air-jet spinning approach. The membranes underwent preparation and characterization through various techniques including Fourier-transform infrared spectroscopy, measurement of water contact angle, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, assessment of in vitro release of curcumin and Ag+, testing of mechanical strength, flexibility, water absorption and biodegradability. In addition, the antioxidant, antibacterial and anti-inflammatory properties of the membranes were evaluated in vitro, and the ability of the membranes to heal wounds was tested in vivo using diabetic mice. Results: Loose hydrophilic nanofibrous membranes with uniform fibre sizes were prepared through air-jet spinning. The membranes enabled the efficient and sustained release of curcumin. More importantly, antibacterial AgNPs were successfully reduced in situ from AgNO3. The incorporation of AgNPs endowed the membrane with superior antibacterial activity, and the bioactivities of curcumin and the AgNPs gave the membrane efficient ROS scavenging and immunomodulatory effects, which protected cells from oxidative damage and reduced inflammation. Further results from animal studies indicated that the PLLA/C/Ag membranes had the most efficient wound healing properties, which were achieved by stimulating angiogenesis and collagen deposition and inhibiting inflammation. Conclusions: In this research, we successfully fabricated PLLA/C/Ag membranes that possess properties of antioxidants, antibacterial agents and anti-inflammatory agents, which can aid in the process of wound healing. Modulating wound inflammation, these new PLLA/C/Ag membranes serve as a novel dressing to enhance the healing of diabetic wounds.

Ultrastrong and High Thermal Insulating Porous High-Entropy Ceramics up to 2000 °C.

High mechanical load-carrying capability and thermal insulating performance are crucial to thermal-insulation materials under extreme conditions. However, these features are often difficult to achieve simultaneously in conventional porous ceramics. Here, for the first time, it is reported a multiscale structure design and fast fabrication of 9-cation porous high-entropy diboride ceramics via an ultrafast high-temperature synthesis technique that can lead to exceptional mechanical load-bearing capability and high thermal insulation performance. With the construction of multiscale structures involving ultrafine pores at the microscale, high-quality interfaces between building blocks at the nanoscale, and severe lattice distortion at the atomic scale, the materials with an ≈50% porosity exhibit an ultrahigh compressive strength of up to ≈337 MPa at room temperature and a thermal conductivity as low as ≈0.76 W m-1 K-1. More importantly, they demonstrate exceptional thermal stability, with merely ≈2.4% volume shrinkage after 2000 °C annealing. They also show an ultrahigh compressive strength of ≈690 MPa up to 2000 °C, displaying a ductile compressive behavior. The excellent mechanical and thermal insulating properties offer an attractive material for reliable thermal insulation under extreme conditions.

Ferroptosis: an important player in the inflammatory response in diabetic nephropathy.

Diabetic nephropathy (DN) is a chronic inflammatory disease that affects millions of diabetic patients worldwide. The key to treating of DN is early diagnosis and prevention. Once the patient enters the clinical proteinuria stage, renal damage is difficult to reverse. Therefore, developing early treatment methods is critical. DN pathogenesis results from various factors, among which the immune response and inflammation play major roles. Ferroptosis is a newly discovered type of programmed cell death characterized by iron-dependent lipid peroxidation and excessive ROS production. Recent studies have demonstrated that inflammation activation is closely related to the occurrence and development of ferroptosis. Moreover, hyperglycemia induces iron overload, lipid peroxidation, oxidative stress, inflammation, and renal fibrosis, all of which are related to DN pathogenesis, indicating that ferroptosis plays a key role in the development of DN. Therefore, this review focuses on the regulatory mechanisms of ferroptosis, and the mutual regulatory processes involved in the occurrence and development of DN and inflammation. By discussing and analyzing the relationship between ferroptosis and inflammation in the occurrence and development of DN, we can deepen our understanding of DN pathogenesis and develop new therapeutics targeting ferroptosis or inflammation-related regulatory mechanisms for patients with DN.

Circular RNAs: An emerging precise weapon for diabetic nephropathy diagnosis and therapy.

Diabetic nephropathy (DN) is a prevalent chronic microvascular complication associated with diabetes mellitus and represents a major cause of chronic kidney disease and renal failure. Current treatment strategies for DN primarily focus on symptom alleviation, lacking effective approaches to halt or reverse DN progression. Circular RNA (circRNA), characterized by a closed-loop structure, has emerged as a novel non-coding RNA regulator of gene expression, attributed to its conservation, stability, specificity, and multifunctionality. Dysregulation of circRNA expression is closely associated with DN progression, whereby circRNA impacts kidney cell injury by modulating cell cycle, differentiation, cell death, as well as influencing the release of inflammatory factors and stromal fibronectin expression. Consequently, circRNA is considered a predictive biomarker and a potential therapeutic target for DN. This review provides an overview of the latest research progress in the classification, functions, monitoring methods, and databases related to circRNA. The paper focuses on elucidating the impact and underlying mechanisms of circRNA on kidney cells under diabetic conditions, aiming to offer novel insights into the prevention, diagnosis, and treatment of DN.

RIPK1 and RIPK3 inhibitors: potential weapons against inflammation to treat diabetic complications.

Diabetes mellitus is a metabolic disease that is characterized by chronic hyperglycemia due to a variety of etiological factors. Long-term metabolic stress induces harmful inflammation leading to chronic complications, mainly diabetic ophthalmopathy, diabetic cardiovascular complications and diabetic nephropathy. With diabetes complications being one of the leading causes of disability and death, the use of anti-inflammatories in combination therapy for diabetes is increasing. There has been increasing interest in targeting significant regulators of the inflammatory pathway, notably receptor-interacting serine/threonine-kinase-1 (RIPK1) and receptor-interacting serine/threonine-kinase-3 (RIPK3), as drug targets for managing inflammation in treating diabetes complications. In this review, we aim to provide an up-to-date summary of current research on the mechanism of action and drug development of RIPK1 and RIPK3, which are pivotal in chronic inflammation and immunity, in relation to diabetic complications which may be benefit for explicating the potential of selective RIPK1 and RIPK3 inhibitors as anti-inflammatory therapeutic agents for diabetic complications.

Research progress on multiple cell death pathways of podocytes in diabetic kidney disease.

Diabetic kidney disease (DKD) is the main cause of end-stage renal disease, and its clinical manifestations are progressive proteinuria, decreased glomerular filtration rate, and renal failure. The injury and death of glomerular podocytes are the keys to DKD. Currently, a variety of cell death modes have been identified in podocytes, including apoptosis, autophagy, endoplasmic reticulum (ER) stress, pyroptosis, necroptosis, ferroptosis, mitotic catastrophe, etc. The signaling pathways leading to these cell death processes are interconnected and can be activated simultaneously or in parallel. They are essential for cell survival and death that determine the fate of cells. With the deepening of the research on the mechanism of cell death, more and more researchers have devoted their attention to the underlying pathologic research and the drug therapy research of DKD. In this paper, we discussed the podocyte physiologic role and DKD processes. We also provide an overview of the types and specific mechanisms involved in each type of cell death in DKD, as well as related targeted therapy methods and drugs are reviewed. In the last part we discuss the complexity and potential crosstalk between various modes of cell death, which will help improve the understanding of podocyte death and lay a foundation for new and ideal targeted therapy strategies for DKD treatment in the future.

Development of a Chimeric Protein BiPPB-mIFNγ-tTßRII for Improving the Anti-Fibrotic Activity in Vivo by Targeting Fibrotic Liver and Dual Inhibiting the TGF-ß1/Smad Signaling Pathway.

Excessive production of transforming growth factor ß1 (TGF-ß1) in activated hepatic stellate cells (aHSCs) promotes liver fibrosis by activating the TGF-ß1/Smad signaling pathway. Thus, specifically inhibiting the pro-fibrotic activity of TGF-ß1 in aHSCs is an ideal strategy for treating liver fibrosis. Overexpression of platelet-derived growth factor ß receptor (PDGFßR) has been demonstrated on the surface of aHSCs relative to normal cells in liver fibrosis. Interferon-gamma peptidomimetic (mIFNγ) and truncated TGF-ß receptor type II (tTßRII) inhibit the TGF-ß1/Smad signaling pathway by different mechanisms. In this study, we designed a chimeric protein by the conjugation of (1) mIFNγ and tTßRII coupled via plasma protease-cleavable linker sequences (FNPKTP) to (2) PDGFßR-recognizing peptide (BiPPB), namely BiPPB-mIFNγ-tTßRII. This novel protein BiPPB-mIFNγ-tTßRII was effectively prepared using Escherichia coli expression system. The active components BiPPB-mIFNγ and tTßRII were slowly released from BiPPB-mIFNγ-tTßRII by hydrolysis using the plasma protease thrombin in vitro. Moreover, BiPPB-mIFNγ-tTßRII highly targeted to fibrotic liver tissues, markedly ameliorated liver morphology and fibrotic responses in chronic liver fibrosis mice by both inhibiting the phosphorylation of Smad2/3 and inducing the expression of Smad7. Meanwhile, BiPPB-mIFNγ-tTßRII markedly reduced the deposition of collagen fibrils and expression of fibrosis-related proteins in acute liver fibrosis mice. Furthermore, BiPPB-mIFNγ-tTßRII showed a good safety performance in both liver fibrosis mice. Taken together, BiPPB-mIFNγ-tTßRII improved the in vivo anti-liver fibrotic activity due to its high fibrotic liver-targeting potential and the dual inhibition of the TGF-ß1/Smad signaling pathway, which may be a potential candidate for targeting therapy on liver fibrosis.

Application of recombinant TGF-ß1 inhibitory peptide to alleviate isoproterenol-induced cardiac fibrosis.

Cardiac fibrosis is a remodeling process of the cardiac interstitium, characterized by abnormal metabolism of the extracellular matrix, excessive accumulation of collagen fibers, and scar tissue hyperplasia. Persistent activation and transdifferentiation into myofibroblasts of cardiac fibroblasts promote the progression of fibrosis. Transforming growth factor-ß1 (TGF-ß1) is a pivotal factor in cardiac fibrosis. Latency-associated peptide (LAP) is essential for activating TGF-ß1 and its binding to the receptor. Thus, interference with TGF-ß1 and the signaling pathways using LAP may attenuate cardiac fibrosis. Recombinant full-length and truncated LAP were previously constructed, expressed, and purified. Their effects on cardiac fibrosis were investigated in isoproterenol (ISO)-induced cardiac fibroblasts (CFs) and C57BL/6 mice. The study showed that LAP and tLAP inhibited ISO-induced CF activation, inflammation, and fibrosis, improved cardiac function, and alleviated myocardial injury in ISO-induced mice. LAP and tLAP alleviated the histopathological alterations and inhibited the elevated expression of inflammatory and fibrosis-related markers in cardiac tissue. In addition, LAP and tLAP decreased the ISO-induced elevated expression of TGF-ß, αvß3, αvß5, p-Smad2, and p-Smad3. The study indicated that LAP and tLAP attenuated ISO-induced cardiac fibrosis via suppressing TGF-ß/Smad pathway. This study may provide a potential approach to alleviate cardiac fibrosis. KEY POINTS: • LAP and tLAP inhibited ISO-induced CF activation, inflammation, and fibrosis. • LAP and tLAP improved cardiac function and alleviated myocardial injury, inflammation, and fibrosis in ISO-induced mice. • LAP and tLAP attenuated cardiac fibrosis via suppressing TGF-ß/Smad pathway.

Severe pigeon paramyxovirus 1 infection in a human case with probable post-COVID-19 condition.

Pigeon paramyxovirus 1 (PPMV-1) is an antigenic host variant of avian paramyxovirus 1. Sporadic outbreaks of PPMV-1 infection have occurred in pigeons in China; however, few cases of human PPMV-1 infection have been reported. The purpose of this article is to report a case of severe human PPMV-1 infection in an individual with probable post-COVID-19 syndrome (long COVID) who presented with rapidly progressing pulmonary infection. The patient was a 66-year-old man who was admitted to the intensive care unit 11 days after onset of pneumonia and recovered 64 days after onset. PPMV-1 was isolated from the patient's sputum and in cloacal smear samples from domesticated pigeons belonging to the patient's neighbour. Residual severe acute respiratory syndrome coronavirus 2 was detected in respiratory and anal swab samples from the patient. Sequencing analyses revealed that the PPMV-1 genome belonged to genotype VI.2.1.1.2.2 and had the 112RRQKRF117 motif in the cleavage site of the fusion protein, which is indicative of high virulence. This case of cross-species transmission of PPMV-1 from a pigeon to a human highlights the risk of severe PPMV-1 infection in immunocompromised patients, especially those with long COVID. Enhanced surveillance for increased risk of severe viral infection is warranted in this population.

Engineered fibrotic liver-targeted truncated transforming growth factor ß receptor type II variant for superior anti-liver fibrosis therapy.

Truncated transforming growth factor ß receptor type II (tTßRII) is a promising anti-liver fibrotic candidate because it serves as a trap for binding excessive TGF-ß1 by means of competing with wild type TßRII (wtTßRII). However, the widespread application of tTßRII for the treatment of liver fibrosis has been limited by its poor fibrotic liver-homing capacity. Herein, we designed a novel tTßRII variant Z-tTßRII by fusing the platelet-derived growth factor ß receptor (PDGFßR)-specific affibody ZPDGFßR to the N-terminus of tTßRII. The target protein Z-tTßRII was produced using Escherichia coli expression system. In vitro and in vivo studies showed that Z-tTßRII has a superior specific fibrotic liver-targeting potential via the engagement of PDGFßR-overexpressing activated hepatic stellate cells (aHSCs) in liver fibrosis. Moreover, Z-tTßRII significantly inhibited cell migration and invasion, and downregulated fibrosis- and TGF-ß1/Smad pathway-related protein levels in TGF-ß1-stimiluated HSC-T6 cells. Furthermore, Z-tTßRII remarkably ameliorated liver histopathology, mitigated the fibrosis responses and blocked TGF-ß1/Smad signaling pathway in CCl4-induced liver fibrotic mice. More importantly, Z-tTßRII exhibits a higher fibrotic liver-targeting potential and stronger anti-fibrotic effects than either its parent tTßRII or former variant BiPPB-tTßRII (PDGFßR-binding peptide BiPPB modified tTßRII). In addition, Z-tTßRII shows no significant sign of potential side effects in other vital organs in liver fibrotic mice. Taken together, we conclude that Z-tTßRII with its a high fibrotic liver-homing potential, holds a superior anti-fibrotic activity in liver fibrosis in vitro and in vivo, which may be a potential candidate for targeted therapy for liver fibrosis.

Ferroptosis, necroptosis and cuproptosis: Novel forms of regulated cell death in diabetic cardiomyopathy.

Diabetes is a common chronic metabolic disease, and its incidence continues to increase year after year. Diabetic patients mainly die from various complications, with the most common being diabetic cardiomyopathy. However, the detection rate of diabetic cardiomyopathy is low in clinical practice, and targeted treatment is lacking. Recently, a large number of studies have confirmed that myocardial cell death in diabetic cardiomyopathy involves pyroptosis, apoptosis, necrosis, ferroptosis, necroptosis, cuproptosis, cellular burial, and other processes. Most importantly, numerous animal studies have shown that the onset and progression of diabetic cardiomyopathy can be mitigated by inhibiting these regulatory cell death processes, such as by utilizing inhibitors, chelators, or genetic manipulation. Therefore, we review the role of ferroptosis, necroptosis, and cuproptosis, three novel forms of cell death in diabetic cardiomyopathy, searching for possible targets, and analyzing the corresponding therapeutic approaches to these targets.

A Cyclopentanone Compound Attenuates the Over-Accumulation of Extracellular Matrix and Fibrosis in Diabetic Nephropathy via Downregulating the TGF-ß/p38MAPK Axis.

Excessive accumulation of the extracellular matrix (ECM) is a crucial pathological process in chronic kidney diseases, such as diabetic nephropathy, etc. The underlying mechanisms of how to decrease ECM deposition to improve diabetic nephropathy remain elusive. The present study investigated whether cyclopentanone compound H8 alleviated ECM over-deposition and fibrosis to prevent and treat diabetic nephropathy. HK-2 cell viability after treatment with H8 was measured by an MTT assay. ECM alterations and renal fibrosis were identified in vitro and in vivo. A pharmacological antagonist was used to detect associations between H8 and the p38 mitogen-activated protein kinase (p38MAPK) signaling pathway. H8 binding was identified through computer simulation methods. Studies conducted on high glucose and transforming growth factor ß1 (TGF-ß1)-stimulated HK-2 cells revealed that the p38MAPK inhibitor SB 202190 and H8 had similar pharmacological effects. In addition, excessive ECM accumulation and fibrosis in diabetic nephropathy were remarkably improved after H8 administration in vivo and in vitro. Finally, the two molecular docking models further proved that H8 is a specific p38MAPK inhibitor that forms a hydrogen bond with the LYS-53 residue of p38MAPK. The cyclopentanone compound H8 alleviated the over-deposition of ECM and the development of fibrosis in diabetic nephropathy by suppressing the TGF-ß/p38MAPK axis.

The mechanisms of ferroptosis and its role in alzheimer's disease.

Alzheimer's disease (AD) accounts for two-thirds of all dementia cases, affecting 50 million people worldwide. Only four of the more than 100 AD drugs developed thus far have successfully improved AD symptoms. Furthermore, these improvements are only temporary, as no treatment can stop or reverse AD progression. A growing number of recent studies have demonstrated that iron-dependent programmed cell death, known as ferroptosis, contributes to AD-mediated nerve cell death. The ferroptosis pathways within nerve cells include iron homeostasis regulation, cystine/glutamate (Glu) reverse transporter (system xc-), glutathione (GSH)/glutathione peroxidase 4 (GPX4), and lipid peroxidation. In the regulation pathway of AD iron homeostasis, abnormal iron uptake, excretion and storage in nerve cells lead to increased intracellular free iron and Fenton reactions. Furthermore, decreased Glu transporter expression leads to Glu accumulation outside nerve cells, resulting in the inhibition of the system xc- pathway. GSH depletion causes abnormalities in GPX4, leading to excessive accumulation of lipid peroxides. Alterations in these specific pathways and amino acid metabolism eventually lead to ferroptosis. This review explores the connection between AD and the ferroptosis signaling pathways and amino acid metabolism, potentially informing future AD diagnosis and treatment methodologies.

Recombinant truncated latency-associated peptide alleviates liver fibrosis in vitro and in vivo via inhibition of TGF-ß/Smad pathway.

BACKGROUND: Liver fibrosis is a progressive liver injury response. Transforming growth factor ß1 (TGF-ß1) is oversecreted during liver fibrosis and promotes the development of liver fibrosis. Therapeutic approaches targeting TGF-ß1 and its downstream pathways are essential to inhibit liver fibrosis. The N-terminal latency-associated peptide (LAP) blocks the binding of TGF-ß1 to its receptor. Removal of LAP is critical for the activation of TGF-ß1. Therefore, inhibition of TGF-ß1 and its downstream pathways by LAP may be a potential approach to affect liver fibrosis. METHODS: Truncated LAP (tLAP) plasmids were constructed. Recombinant proteins were purified by Ni affinity chromatography. The effects of LAP and tLAP on liver fibrosis were investigated in TGF-ß1-induced HSC-T6 cells, AML12 cells and CCl4-induced liver fibrosis mice by real time cellular analysis (RTCA), western blot, real-time quantitative PCR (RT-qPCR), immunofluorescence and pathological staining. RESULTS: LAP and tLAP could inhibit TGF-ß1-induced AML12 cells inflammation, apoptosis and EMT, and could inhibit TGF-ß1-induced HSC-T6 cells proliferation and fibrosis. LAP and tLAP could attenuate the pathological changes of liver fibrosis and inhibit the expression of fibrosis-related proteins and mRNAs in CCl4-induced liver fibrosis mice. CONCLUSION: LAP and tLAP could alleviate liver fibrosis in vitro and in vivo via inhibition of TGF-ß/Smad pathway. TLAP has higher expression level and more effective anti-fibrosis activity compared to LAP. This study may provide new ideas for the treatment of liver fibrosis.

11ß-HSD1 Inhibitor Alleviates Non-Alcoholic Fatty Liver Disease by Activating the AMPK/SIRT1 Signaling Pathway.

We investigated the effect of an 11ß-HSD1 inhibitor (H8) on hepatic steatosis and its mechanism of action. Although H8, a curcumin derivative, has been shown to alleviate insulin resistance, its effect on non-alcoholic fatty liver disease (NAFLD) remains unknown. Rats were fed a high-fat diet (HFD) for 8 weeks, intraperitoneally injected with streptozotocin (STZ) to induce NAFLD, and, then, treated with H8 (3 or 6 mg/kg/day) or curcumin (6 mg/kg/day) for 4 weeks, to evaluate the effects of H8 on NAFLD. H8 significantly alleviated HFD+STZ-induced lipid accumulation, fibrosis, and inflammation as well as improved liver function. Moreover, 11ß-HSD1 overexpression was established by transfecting animals and HepG2 cells with lentivirus, carrying the 11ß-HSD1 gene, to confirm that H8 improved NAFLD, by reducing 11ß-HSD1. An AMP-activated protein kinase (AMPK) inhibitor (Compound C, 10 µM for 2 h) was used to confirm that H8 increased AMPK, by inhibiting 11ß-HSD1, thereby restoring lipid metabolic homeostasis. A silencing-related enzyme 1 (SIRT1) inhibitor (EX572, 10 µM for 4 h) and a SIRT1 activator (SRT1720, 1 µM for 4 h) were used to confirm that H8 exerted anti-inflammatory effects, by elevating SIRT1 expression. Our findings demonstrate that H8 alleviates hepatic steatosis, by inhibiting 11ß-HSD1, which activates the AMPK/SIRT1 signaling pathway.

Heparan sulfate proteoglycans-mediated targeted delivery of TGF-ß1-binding peptide to liver for improved anti-liver fibrotic activity in vitro and in vivo.

Elevated expressions of transforming growth factor ß1 (TGF-ß1) have been implicated in the pathogenesis of liver fibrosis, thus attenuating the excessive TGF-ß1's activity by TGF-ß1-binding peptide is an ideal strategy for the treatment of liver fibrosis. However, the application of small peptide as a pharmaceutical agent is obstacle due to difficult preparation and non-selective delivery. The I-plus sequences of circumsporozoite protein (CSP-I) possesses high affinity for heparan sulfate proteoglycans, which are primarily located on liver tissues. TGF-ß1-binding peptide P15 holds specific ability of binding to TGF-ß1. In this study, we describe an approach to efficiently preparing liver-targeting peptide P15-CSP-I, which is conjugation of the sequences of P15 to the N-terminus of CSP-I, from the cleavage of biological macromolecule SUMO-tagged P15-CSP-I. In vitro and ex vivo binding assay showed that P15-CSP-I specifically targeted to the hepatocytes and liver tissues. Moreover, P15-CSP-I inhibited cell proliferation, migration and invasion, and decreased fibrosis-related proteins expression in TGF-ß1-activated HSCs in vitro. Furthermore, P15-CSP-I ameliorated liver morphology and decreased the fibrosis responses in vivo. Taken together, P15-CSP-I may be a potential candidate for targeting therapy on liver fibrosis due to its high efficient preparation, specific liver-targeting potential and improved anti-liver fibrotic activity.

Prokaryotic expression, purification and evaluation of anti-cardiac fibrosis activity of recombinant TGF-ß latency associated peptide.

BACKGROUND: Cardiac fibrosis refers to the abnormal accumulation of extracellular matrix in the heart, which leads to the formation of cardiac scars. It causes systolic and diastolic dysfunction, and ultimately leads to cardiac dysfunction and arrhythmia. TGF-ß1 is an important regulatory factor involved in cardiac fibrosis. Studies have shown that the N-terminal latency associated peptide (LAP) must be removed before TGF-ß1 is activated. We hypothesize that recombinant LAP may inhibit cardiac fibrosis induced by TGF-ß1. To evaluate anti-cardiac fibrosis activity of recombinant LAP, an experimental study was carried out and is reported here. METHODS: The pET28a-LAP plasmid was constructed and transformed into E. coli C43 (DE3) competent cells. The recombinant LAP protein was purified by Ni affinity chromatography. The cells were treated with TGF-ß1 at different concentrations for 24 h. The expression of α-SMA was detected by Western blot. RTCA was used to detect the effect of recombinant LAP on the proliferation of H9C2 cells induced by 10 ng/mL TGF-ß1. To detect the effect of LAP on the expression of fibrosis-related proteins, H9C2 cells were treated with 10 ng/mL TGF-ß1 for 24 h, then added 60 µg/mL recombinant LAP for 48 h. The LAP group was treated with 60 µg/mL recombinant LAP alone. The LAP pre-protection group was treated with 10 ng/mL TGF-ß1 and 60 µg/mL recombinant LAP at the same time. Western blot and immunofluorescence were used to detect the expression of α-SMA, collagen I and fibronectin and p-Smad2. RESULTS: The recombinant LAP was prokaryotic expressed and purified. 10 ng/mL was determined as the optimal working concentration of TGF-ß1 to induce H9C2 cells fibrosis. RTCA results showed that 60 µg/mL LAP could effectively inhibit the proliferation of H9C2 cells induced by TGF-ß1. Immunofluorescence results showed that compared with the control group, the fluorescence intensities of α-SMA, collagen I and FN increased significantly after TGF-ß1 treatment. The fluorescence intensities in the TGF-ß1+LAP group decreased significantly. Western blot results showed that 60 µg/mL LAP could inhibit the increase of α-SMA, collagen I and FN expression in H9C2 cells induced by TGF-ß1. Compared with the control, the LAP alone group has no significant difference in α-SMA and p-Smad2 expression level. The expression of α-SMA and p-Smad2 in the TGF-ß1 model group was significantly increased compared with the control group. Compared with the TGF-ß1 group, both TGF-ß1+LAP group and LAP pre-protection group significantly reduced the increase in α-SMA and p-Smad2 levels. CONCLUSIONS: Recombinant LAP was prokaryotic expressed and purified. The results showed that recombinant LAP can inhibit the cell proliferation and expression increase of α-SMA, collagen I, fibronectin and p-Smad2 in H9C2 cells induced by TGF-ß1. These results suggested that recombinant LAP might inhibit TGF-ß1-induced fibrosis of H9C2 cells through the TGF-ß/Smad pathway.

Targeted truncated TGF-ß receptor type II delivery to fibrotic liver by PDGFß receptor-binding peptide modification for improving the anti-fibrotic activity against hepatic fibrosis in vitro and in vivo.

Truncated transforming growth factor-ß receptor type II (tTßRII) is a promising anti-fibrotic candidate because it attenuates excessive transforming growth factor-ß1 (TGF-ß1) and then blocks TGF-ß1 activity in hepatic fibrosis. However, its use has been greatly limited due to the fact that it is expensive to chemically synthesize and it does not specifically target to the lesion site. In this study, we describe that platelet-derived growth factor ß receptor (PDGFßR)-binding peptide BiPPB modified tTßRII (BiPPB-tTßRII) was prepared from the cleavage of SUMO-BiPPB-tTßRII by digestion with SUMO-specific protease. Moreover, compared to the unmodified tTßRII, the target protein BiPPB-tTßRII not only highly specific targeted activated hepatic stellate cells (HSCs) and fibrotic liver tissue, but also significantly inhibited the protein levels of fibrosis-related genes in TGF-ß1-induced HSC-T6 cells and CCl4-induced liver fibrosis in mice. Furthermore, BiPPB-tTßRII markedly ameliorated liver morphology, fibrotic responses and the damage of liver function in fibrosis animal. More importantly, BiPPB-tTßRII showed a much lesser extent in binding to quiescent HSCs and non-fibrotic liver tissue. Taken together, our results suggested that the target protein BiPPB-tTßRII, with its high specific fibrotic liver-targeting potential and its improved anti-fibrotic activity in liver fibrosis, may be a potential therapeutic agent for liver fibrosis.

Mesenchymal Stem Cells: An Overview of Their Potential in Cell-Based Therapy for Diabetic Nephropathy.

Diabetic nephropathy (DN) is a devastating complication associated with diabetes mellitus, and it is the leading cause of end-stage renal diseases (ESRD). Over the last few decades, numerous studies have reported the beneficial effects of stem cell administration, specifically mesenchymal stem or stromal cells (MSCs), on tissue repair and regeneration. MSC therapy has been considered a promising strategy for ameliorating the progression of DN largely based on results obtained from several preclinical studies and recent Phase I/II clinical trials. This paper will review the recent literature on MSC treatment in DN. In addition, the roles and potential mechanisms involved in MSC treatment of DN will be summarized, which may present much needed new drug targets for this disease. Moreover, the potential benefits and related risks associated with the therapeutic action of MSCs are elucidated and may help in achieving a better understanding of MSCs.

Diverse clinical processes of 16 COVID-19 cases who concentrated infection in the same workplace in Beijing, China: An observational study.

ABSTRACT: Since December 2019, an outbreak of COVID-19 sweeping the world. Understanding the clinical and SARS-CoV-2 dynamic changes of mild and ordinary patients of COVID-19, so as to provide basis for the prevention and control of COVID-19.On February 1st, 2020, 16 SARS-CoV-2 RNA positive patients diagnosed in the same site in Beijing. The patients symptoms, signs, medication, and SARS-CoV-2 results were recorded.Of the 16 patients, 12 were female. Although they were infected at the same time in the same workplace, their clinical processes were very different and can be roughly divided into three different types: persistent sputum positive, persistent stool positive and persistent both positive. In 7 patients with mild clinical manifestations, the median days of SARS-CoV-2 RNA negative conversion in sputum samples were significantly later than those with obvious lung injury (27 days [range: 18 to 36]; 17 days, [range 6 to 25], P = .021). The negative conversion of SARS-CoV-2 RNA in stool was significant later than in sputum.There were various clinical manifestations after SARS-CoV-2 infection, even if they were infected by the same source of infection in the same place. The presence of SARS-CoV-2 virus RNA in stool samples was longer than that in respiratory tract.