Artesunate protects against surgery-induced knee arthrofibrosis by activating Beclin-1-mediated autophagy via inhibition of mTOR signaling

Artesunate attenuates skin hypertrophic scar formation by inhibiting fibroblast activation and EndMT of vascular endothelial cells

Background Hypertrophic scarring is an abnormal condition involving excessive fibroblast activation, aberrant extracellular matrix deposition, and persistent inflammation. Current treatments have limited efficacy and potential adverse effects, necessitating the development of new approaches. Purpose In this study, we investigated the effects of artesunate (ART) on hypertrophic scar (HS) formation and explored the underlying cellular and molecular mechanisms. Methods ART was local injected in rabbit ear HS model to study its effect on HS formation. Cell viability was assessed using the CCK8 assay. Cell proliferation and targeted protein expression were detected by flow cytometry, immunofluorescence and immunohistochemistry staining. Scratch assays were performed to evaluate cell migration, while western blotting analysis was used to detect changes in protein expression. Results Local injection of ART significantly reduced scar protrusion and thickness, improved the immune microenvironment, and attenuated collagen deposition. ART suppressed fibroblast activation, endothelial-mesenchymal transition (EndMT), and angiogenesis in HS tissues. In vitro, ART inhibited TGF-β1-triggered fibroblasts activation and EndMT of human umbilical vein endothelial cells. Mechanistically, ART attenuated the activation of PI3K/AKT/mTOR and TGF-β/Smad pathways in both fibroblasts and human umbilical vein endothelial cells. Notably, the mTOR activator 740 Y-P reversed the fibrosis-inhibiting effects of ART in vitro and in vivo, highlighting the critical and intriguing role of PI3K/AKT/mTOR signaling in mediating the effects of ART. Furthermore, we first uncovered a crosstalk between PI3K/AKT/mTOR and TGF-β/Smad pathways, wherein PI3K/AKT/mTOR inactivation by ART partially contributed to the inhibition of TGF-β/Smad signaling. Conclusion In addition to fibroblast activation, our findings first demonstrate that ART effectively mitigates HS formation by modulating the immune microenvironment and inhibiting EndMT and fibroblast activation. These results provide new perspectives into the development of HS and underscore the promising potential of ART as a therapeutic option for debilitating condition.

Artesunate-multiple pharmacological effects beyond treating malaria

Artesunate, a semisynthetic derivative of artemisinin, is not only recommended as the first-line drug for treating severe malaria but is also a significant member of Artemisinin-based Combination Therapies (ACTs), used in combination with other artemisinin derivatives for treating uncomplicated malaria. Beyond its potent anti-malarial activity, artesunate has garnered considerable attention for its pharmacological effects, which encompass broad-spectrum anti-tumor, anti-viral, and anti-inflammatory properties. It has collectively demonstrated superior drug tolerance, low toxicity, and mild side effects in cell line experiments in vitro, experimental animal models, and clinical drug researches, as a monotherapy or in combination with other agents. Investigating the pharmacological effects of artesunate will facilitate the exploration of novel drug applications and enhance the comprehensive clinical applications.

Extracorporeal Shock Wave and Melatonin Alleviate Joint Capsule Fibrosis after Knee Trauma in Rats by Regulating Autophagy

BACKGROUND

Joint contracture is a common clinical problem affecting joint function. Capsule fibrosis plays a pivotal role in the progression of joint contracture. Previous studies have reported that autophagy plays a regulatory role in visceral fibrosis.

OBJECTIVE

This study aimed to investigate whether extracorporeal shock wave therapy (ESWT) and melatonin alleviate joint capsule fibrosis in rats with extended knee joint contracture by regulating autophagy.

METHODS

A rat traumatic knee joint extension contracture model was made. Then, the rats were treated with ESWT, melatonin, ESWT + melatonin, or ESWT + melatonin + mTOR agonist for 4 weeks. The range of motion (ROM) of the knee joints was measured. Joint capsules were collected and observed for pathological changes by H&E and Masson staining. LC3B protein expression was evaluated by immunofluorescence staining. TGF-β1, MMP-1, Col-Ⅰ, Col-Ⅲ, LC3, ATG7, Beclin1, p-AMPK, p-mTOR and p-ULK1 protein expressions were measured by Western blot assay.

RESULTS

The intervention groups had significantly improved ROM of knee joint (P < 0.05), significantly improved pathological changes on HE and Masson staining, significantly decreased protein expressions of TGF-β1, MMP-1, Col-Ⅰ, Col-Ⅲ and pmTOR (P < 0.05), and significantly increased protein expressions of LC3B, LC3II/LC3I ratio, ATG7, Beclin1, p-AMPK, and p-ULK1 (P < 0.05). Among these groups, the effects demonstrated by the ESWT + melatonin group were the best. With the mTOR agonist supplement, the therapeutic effects of extracorporeal shock waves and melatonin were significantly reduced.

CONCLUSION

ESWT plus melatonin alleviated knee joint capsule fibrosis in rats by regulating autophagy.

Artesunate: A potential drug for the prevention and treatment from hepatitis to hepatocellular carcinoma

Liver cancer represents a multifactorial, multistage, and intricately progressive malignancy. Over the past decade, artesunate (ART), initially renowned for its anti-malarial efficacy, has been the focus of over 3000 studies uncovering its diverse pharmacological actions, including anti-inflammatory, immunoregulatory, metabolic regulatory, anti-fibrotic, and anti-cancer properties. This review highlights ART's role in the multistep progression from hepatitis to cancer and its underlying regulatory mechanisms, revealing signal transducer and activator of transcription 3 (STAT3) and ferroptosis (a novel form of programmed cell death) as promising therapeutic targets. ART demonstrates efficacy in inhibiting hepatitis virus infections, modulating inflammation, and facilitating recovery from inflammatory processes. During stages of hepatic fibrosis or cirrhosis, ART reverses fibrotic and cirrhotic changes by suppressing hepatic stellate cell activity, regulating inflammatory pathways, inhibiting hematopoietic stem cell proliferation, and inducing ferroptosis. Additionally, ART hinders hepatocellular carcinoma (HCC) cell proliferation, invasion, and metastasis, induces apoptosis and autophagy, combats drug resistance, and enhances chemosensitivity. Collectively, ART exhibits multi-step actions across multiple targets and signaling pathways, highlighting its potential as a clinical candidate for the prevention and treatment of liver cancer, from hepatitis and hepatic fibrosis to advanced HCC.

Target NF-κB p65 for preventing posttraumatic joint contracture in rats

RelA/p65 is as a crucial component of the nuclear factor κB (NF-κB) signaling pathway that has a significant impact on various fibrotic diseases. However, its role in the fibrosis of tissues surrounding the joint after traumatic injury remains unclear. In this study, rats were divided into three groups: non-operated control (NC) group, p65-siRNA treated (siRNA-p65) group, and negative siRNA treated (siRNA-neg) group. Then, 10 μL (10 nmol) of p65-siRNA was injected into the joint of the siRNA-p65 group. Meanwhile, 10 μL of negative siRNA was administered to the knee joint of the operated siRNA-neg group for comparison. The rats in the NC group did not receive surgery or drug intervention. After 4 weeks of right knee fixation in each group, X-ray measurements revealed significantly reduced degree of knee flexion contracture following p65-siRNA treatment (siRNA-neg: 77.73° ± 2.799°; siRNA-p65: 105.7° ± 2.629°, p < 0.0001). Histopathological examination revealed that the number of dense fibrous connective tissues decreased following p65-siRNA inhibition. Western blot analysis revealed significantly different expression levels of fibrosis-related proteins between the siRNA-p65 and siRNA-neg groups. Immunohistochemical analysis revealed a reduction in the average number of myofibroblasts in the siRNA-p65 group compared with that in the siRNA-neg group. Thus, intra-articular p65-siRNA injection could attenuate fibroblast activation and fibrosis-related protein production, suppress periarticular tissue fibrosis, and prevent joint contracture by downregulating the NF-κB p65 pathway. Statement of clinical significance: Intra-articular injection of p65-siRNA could reduce myofibroblast proliferation and fibrosis-related protein expression by downregulating the NF-κB p65 pathway, inhibit periarticular tissue fibrosis, and prevent joint adhesion, which represents a potential therapy in the prevention of joint fibrosis following traumatic injury.

Artesunate Exerts Organ- and Tissue-Protective Effects by Regulating Oxidative Stress, Inflammation, Autophagy, Apoptosis, and Fibrosis: A Review of Evidence and Mechanisms

The human body comprises numerous organs and tissues operating in synchrony, it facilitates metabolism, circulation, and overall organismal function. Consequently, the well-being of our organs and tissues significantly influences our overall health. In recent years, research on the protective effects of artesunate (AS) on various organ functions, including the heart, liver, brain, lungs, kidneys, gastrointestinal tract, bones, and others has witnessed significant advancements. Findings from in vivo and in vitro studies suggest that AS may emerge as a newfound guardian against organ damage. Its protective mechanisms primarily entail the inhibition of inflammatory factors and affect anti-fibrotic, anti-aging, immune-enhancing, modulation of stem cells, apoptosis, metabolic homeostasis, and autophagy properties. Moreover, AS is attracting a high level of interest because of its obvious antioxidant activities, including the activation of Nrf2 and HO-1 signaling pathways, inhibiting the release of reactive oxygen species, and interfering with the expression of genes and proteins associated with oxidative stress. This review comprehensively outlines the recent strides made by AS in alleviating organismal injuries stemming from various causes and protecting organs, aiming to serve as a reference for further in-depth research and utilization of AS.

Pharmacological prevention of arthrofibrosis: a systematic review

BACKGROUND AND AIMS

Arthrofibrosis is a complication of intra-articular knee surgery which is caused by intra-articular fibrosis. To date, several preventive therapies for arthrofibrosis have been reported. This systematic review aims to summarize current knowledge about pharmacological arthrofibrosis prevention.

METHODS

A systematic literature search was conducted in Medline, Web of Science, and Cochrane library using the search term 'Arthrofibrosis AND prevention'. Subsequently, articles reporting the effects of a preventive pharmacological intervention against arthrofibrosis were included in this review.

RESULTS

16 studies investigated the pharmacological prevention of arthrofibrosis of which 13 were conducted in animal models. Several drugs improved the range of motion (ROM) in animal models. Bevacizumab (ROM +39.4 degrees), nonsteroidal anti-inflammatory drugs (ROM +18.0-31.2 degrees), and rosiglitazone (ROM +19.5 degrees) significantly increased the ROM. Artesunate, mitomycin c, bevacizumab, hyaloglide, and botulinum toxin A significantly reduced adhesion scores. None of the drugs tested in humans improved the functional outcomes after joint arthroplasty. Methodological differences limited the ability to compare outcomes and, due to poor reporting of methodology, many studies had an unclear risk of bias.

CONCLUSION

This review identified several drugs as potential candidates for arthrofibrosis prevention. These drugs modulate inflammation or alter the activity of fibroblasts. Most studies are conducted in experimental animal models and none of these results are currently translated into a clinical application. Moreover, the methodology and route of administration varied between studies. Nor were dose dependency studies conducted. Future studies should adopt a standardized approach to determine the effects of preventive pharmacological interventions on arthrofibrosis.

Artesunate-loaded solid lipid nanoparticles resist esophageal squamous cell carcinoma by inducing Ferroptosis through inhibiting the AKT/mTOR signaling

Esophageal squamous cell carcinoma (ESCC) is a severe malignancy with high incidence and mortality rate in China, while the application of standard chemotherapeutic drugs for ESCC meets the barriers of high toxicity and multiple drug resistance (MDR). In recent years, the anticancer effects of artesunate (ART), a Chinese medicine monomer have gained extensive attentions due to its characteristics of low toxicity, high potency, and reversal of MDR. In this study, we develop the artesunate-loaded solid lipid nanoparticles (SLNART) to overcome the poor water solubility and bioavailability of ART, further improving the efficiency of ART on ESCC treatment. Especially mentioned, SLNART is shown to present marked inhibitory effects on ESCC development based on the induction of ferroptosis by two pathways included upregulating TFR to increase Fe2+ ions and inhibiting the AKT/mTOR signaling to downregulate GPX4. Collectively, this study is the first to pave a promising approach for ESCC therapy based on a strategy of developing SLNART to induce ferroptosis by mediating Fe2+ ions and AKT/mTOR signaling.

Human Infrapatellar Fat Pad Mesenchymal Stem Cell-Derived Extracellular Vesicles Inhibit Fibroblast Proliferation by Regulating MT2A to Reduce Knee Arthrofibrosis

Knee arthrofibrosis is one of the most serious complications of knee surgery; however, its pathogenesis is unclear, and current treatment methods have not achieved satisfactory results. Mesenchymal stem cells (MSCs) have good anti-inflammatory and antifibrotic properties, and studies have reported that human infrapatellar fat pad-derived MSCs (IPFSCs) have the advantages of strong proliferative and differentiating ability, ease of acquisition, and minimal harm to the donor. Increasing evidence has shown that MSCs function through their paracrine extracellular vesicles (EVs). Our study is aimed at exploring the effects of human IPFSC-derived EVs (IPFSC-EVs) on knee arthrofibrosis and the underlying mechanisms in vivo and in vitro. In the in vivo study, injecting IPFSC-EVs into the knee joint cavity effectively reduced surgery-induced knee arthrofibrosis in rats. In the in vitro study, IPFSC-EVs were found to inhibit the proliferation of fibroblasts in the inflammatory environment. Additionally, we screened a potential IPFSC-EV molecular target, metallothionein 2A (MT2A), using RNA sequencing. We found that silencing MT2A partially reversed the inhibitory effect of IPFSC-EVs on fibroblast proliferation in the inflammatory environment. In conclusion, IPFSC-EVs inhibit the progression of knee arthrofibrosis by regulating MT2A, which inhibits fibroblast proliferation in the inflammatory environment.

Therapeutic potential of artemisinin and its derivatives in managing kidney diseases

Artemisinin, an antimalarial traditional Chinese herb, is isolated from Artemisia annua. L, and has shown fewer side effects. Several pieces of evidence have demonstrated that artemisinin and its derivatives exhibited therapeutic effects on diseases like malaria, cancer, immune disorders, and inflammatory diseases. Additionally, the antimalarial drugs demonstrated antioxidant and anti-inflammatory activities, regulating the immune system and autophagy and modulating glycolipid metabolism properties, suggesting an alternative for managing kidney disease. This review assessed the pharmacological activities of artemisinin. It summarized the critical outcomes and probable mechanism of artemisinins in treating kidney diseases, including inflammatory, oxidative stress, autophagy, mitochondrial homeostasis, endoplasmic reticulum stress, glycolipid metabolism, insulin resistance, diabetic nephropathy, lupus nephritis, membranous nephropathy, IgA nephropathy, and acute kidney injury, suggesting the therapeutic potential of artemisinin and its derivatives in managing kidney diseases, especially the podocyte-associated kidney diseases.

Biochemical markers of postsurgical knee arthrofibrosis: A systematic review

Introduction

Postsurgical knee arthrofibrosis is a common complication associated with pain and limited range of motion. Although the mechanism is unclear, many biochemical and genetic markers have been identified within arthrofibrotic knees. The purpose of this systematic review is to synthesize the many biochemical and genetic markers that have been associated with surgery-induced knee arthrofibrosis in order to better guide future therapeutic endeavors.

Methods

A thorough search of literature was conducted on April 27, 2022. Seventeen studies met inclusion criteria for this systematic review. Inclusion criteria for this study were as follows: title or abstract discussed biochemical and genetic markers associated with postoperative knee arthrofibrosis, study design included human and/or animal subjects.

Results

A wide variety of genetic biomarkers (mRNA), proteins/enzymes, and cytokines were identified in both animal models and human subjects with postsurgical knee arthrofibrosis. These included various extracellular matrix-encoding mRNA sequences, matrix metalloproteinases, proteins and mRNA sequences involved in Transforming Growth Factor-β signaling, and interleukin-family cytokines to name just a few.

Conclusion

There are many biomarkers found in postsurgical arthrofibrotic knees. TGF-β, and mRNA/proteins that participate in TGF-β signaling (i.e., LOX, SERPINE1, PAI-1/Akt/mTOR, BMP-2), appear to be particularly common. Future comparative studies should aim to determine which of these are most relevant, and therefore, worthwhile therapeutic targets.

Artemisinin derivative SM934 in the treatment of autoimmune and inflammatory diseases: therapeutic effects and molecular mechanisms

Artemisinin and its derivatives are the well-known anti-malarial drugs derived from a traditional Chinese medicine. In addition to antimalarial, artemisinin and its derivatives possess distinguished anti-cancer, anti-oxidant, anti-inflammatory and anti-viral activities, but the poor solubility and low bioavailability hinder their clinical application. In the last decades a series of new water-soluble and oil-soluble derivatives were synthesized. Among them, we have found a water-soluble derivative β-aminoarteether maleate (SM934) that exhibits outstanding suppression on lymphocytes proliferation in immunosuppressive capacity and cytotoxicity screening assays with 35-fold higher potency than dihydroartemisinin. SM934 displays significant therapeutic effects on various autoimmune and inflammatory diseases, including systemic lupus erythematosus, antiphospholipid syndrome nephropathy, membranous nephropathy, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and dry eye disease. Here, we summarize the immunomodulatory effects, anti-inflammatory, anti-oxidative and anti-fibrosis activities of SM934 in disease-relevant animal models and present the probable pharmacological mechanisms involved in its therapeutic efficacy. This review also delineates a typical example of natural product-based drug discovery, which might further vitalize natural product exploration and development in pharmacotherapy.

Human outgrowth knee fibroblasts from patients undergoing total knee arthroplasty exhibit a unique gene expression profile and undergo myofibroblastogenesis upon TGFβ1 stimulation

Arthrofibrosis is characterized by excessive extracellular matrix (ECM) deposition that results in restricted joint motion after total knee arthroplasties (TKAs). Currently, treatment options are limited. Therefore, an in vitro model of knee-related myofibroblastogenesis is valuable to facilitate investigation of the arthrofibrotic process, diagnostic and therapeutic options. In this study, we obtained intraoperative posterior capsule (PC), quadriceps tendon (QT), and suprapatellar pouch (SP) tissues from the knees of four patients undergoing primary TKAs for osteoarthritis. From these tissues, we isolated primary cells by the outgrowth method and subsequently characterized these cells in the absence and presence of the pro-myofibroblastic cytokine, transforming growth factor beta 1 (TGFβ1). Light microscopy of knee outgrowth cells revealed spindle-shaped cells, and immunofluorescence (IF) analysis demonstrated staining for the fibroblast-specific markers TE-7 and vimentin (VIM). These knee outgrowth fibroblasts differentiated readily into myofibroblasts as reflected by enhanced α-smooth muscle actin (ACTA2) mRNA and protein expression and increased mRNA expression of collagen type 1 (COL1A1) and type 3 (COL3A1) with collagenous matrix deposition in the presence of TGFβ1. Outgrowth knee fibroblasts were more sensitive to TGFβ1-mediated myofibroblastogenesis than adipose-derived mesenchymal stromal/stem cells (MSCs). While outgrowth knee fibroblasts isolated from three anatomical regions in four patients exhibited similar gene expression, these cells are distinct from other fibroblastic cell types (i.e., Dupuytren's fibroblasts) as revealed by RNA-sequencing. In conclusion, our study provides an in vitro myofibroblastic model of outgrowth knee fibroblasts derived from patients undergoing primary TKA that can be utilized to study myofibroblastogenesis and assess therapeutic strategies for arthrofibrosis.

Recent Advances in the Therapeutic Efficacy of Artesunate

Artesunate, a semisynthetic artemisinin derivative, is well-known and used as the first-line drug for treating malaria. Apart from treating malaria, artesunate has also been found to have biological activity against a variety of cancers and viruses. It also exhibits antidiabetic, anti-inflammatory, anti-atherosclerosis, immunosuppressive activities, etc. During its administration, artesunate can be loaded in liposomes, alone or in combination with other therapeutic agents. Administration routes include intragastrical, intravenous, oral, and parenteral. The biological activity of artesunate is based on its ability to regulate some biological pathways. This manuscript reports a critical review of the recent advances in the therapeutic efficacy of artesunate.

Luteolin alleviates inorganic mercury-induced kidney injury via activation of the AMPK/mTOR autophagy pathway

Inorganic mercury is a ubiquitous toxic pollutant in the environment. Exposure to inorganic mercury can cause various poisonous effects, including kidney injury. However, no safe and effective treatment for kidney injury caused by inorganic mercury has been found and used. Luteolin (Lut) possesses various beneficial bioactivities. Here, our research aims to investigate the protective effect of Lut on renal injury induced by mercury chloride (HgCl₂) and identify the underlying autophagy regulation mechanism. Twenty-eight 6-8 weeks old Wistar rats were randomly assigned to four groups: control, HgCl₂, HgCl₂ + Lut, and Lut. We performed the determination of oxidative stress and renal function indicators, histopathological analysis, the terminal deoxynucleotidyl transferase-mediated deoxyuracil nucleoside triphosphate nick-end labeling assay to detect apoptosis, western blot detection of autophagy-related protein levels, and atomic absorption method to detect mercury content. Our results showed that Lut ameliorated oxidative stress, apoptosis and restored the autophagy and renal function caused by HgCl₂ in rats. Concretely, the level of nuclear factor E2-related factor, renal adenosine monophosphate-activated protein kinase (AMPK) expression, and autophagy regulation-related proteins levels were down-regulated, and the mammalian target of rapamycin (mTOR) expression was up-regulated by HgCl₂ treatment. However, Lut treatment reversed the above changes. Notably, Lut reduced the accumulation of HgCl₂ in the kidneys and promoted the excretion of HgCl₂ through urine. Collectively, our results demonstrate that Lut can attenuate inorganic mercury-induced renal injury via activating the AMPK/mTOR autophagy pathway. Therefore, Lut may be a potential biological medicine to protect against renal damage induced by HgCl₂.

The immunosuppressive activity of artemisinin-type drugs towards inflammatory and autoimmune diseases

The sesquiterpene lactone artemisinin from Artemisia annua L. is well established for malaria therapy, but its bioactivity spectrum is much broader. In this review, we give a comprehensive and timely overview of the literature regarding the immunosuppressive activity of artemisinin-type compounds toward inflammatory and autoimmune diseases. Numerous receptor-coupled signaling pathways are inhibited by artemisinins, including the receptors for interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), β3-integrin, or RANKL, toll-like receptors and growth factor receptors. Among the receptor-coupled signal transducers are extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), AKT serine/threonine kinase (AKT), mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK) kinase (MEK), phospholipase C γ1 (PLCγ), and others. All these receptors and signal transduction molecules are known to contribute to the inhibition of the transcription factor nuclear factor κ B (NF-κB). Artemisinins may inhibit NF-κB by silencing these upstream pathways and/or by direct binding to NF-κB. Numerous NF-κB-regulated downstream genes are downregulated by artemisinin and its derivatives, for example, cytokines, chemokines, and immune receptors, which regulate immune cell differentiation, apoptosis genes, proliferation-regulating genes, signal transducers, and genes involved in antioxidant stress response. In addition to the prominent role of NF-κB, other transcription factors are also inhibited by artemisinins (mammalian target of rapamycin [mTOR], activating protein 1 [AP1]/FBJ murine osteosarcoma viral oncogene homologue [FOS]/JUN oncogenic transcription factor [JUN]), hypoxia-induced factor 1α (HIF-1α), nuclear factor of activated T cells c1 (NF-ATC1), Signal transducers and activators of transcription (STAT), NF E2-related factor-2 (NRF-2), retinoic-acid-receptor-related orphan nuclear receptor γ (ROR-γt), and forkhead box P-3 (FOXP-3). Many in vivo experiments in disease-relevant animal models demonstrate therapeutic efficacy of artemisinin-type drugs against rheumatic diseases (rheumatoid arthritis, osteoarthritis, lupus erythematosus, arthrosis, and gout), lung diseases (asthma, acute lung injury, and pulmonary fibrosis), neurological diseases (autoimmune encephalitis, Alzheimer's disease, and myasthenia gravis), skin diseases (dermatitis, rosacea, and psoriasis), inflammatory bowel disease, and other inflammatory and autoimmune diseases. Randomized clinical trials should be conducted in the future to translate the plethora of preclinical results into clinical practice.

Overexpression of laminin α4 facilitates proliferation and migration of fibroblasts in knee arthrofibrosis by targeting canonical Shh/Gli1 signaling

Aim: Pathologic hyperplasia of fibroblast is responsible for the progression of intraarticular fibrosis. Laminin α4 (LAMA4), a subunit of laminin macromolecule family, was found to be overexpressed in various fibrotic tissues. However, the role of LAMA4 in knee arthrofibrosis remains elusive. Therefore, the aim of this study was to investigate the effect and mechanism of LAMA4 on fibroblast proliferation and migration. Materials and methods: Following knee surgery, LAMA4 expression was detected in intraarticular fibrous tissues in rabbits at week 2 and week 4, respectively. In lentivirus-mediated LAMA4-overexpressed fibroblasts, cellular proliferation was assessed by EdU labeling and cell cycle analysis, cellular migration was evaluated using Transwell assay, and the expressions of key components in Shh/Gli1 signaling were detected by qRT-PCR, western blot and immunofluorescence analysis. Additionally, canonical Shh cascade was further blocked in LAMA4-overexpressed fibroblasts by cyclopamine, and the changes in cellular proliferation and migration were investigated. Results: LAMA4 expression was positively correlated with the severity of knee arthrofibrosis. Functional studies demonstrated that LAMA4 overexpression facilitated proliferation, cell cycle progression and migration in fibroblasts. Mechanically, LAMA4 activated the canonical Shh/Gli1 signaling and promoted the nuclear translocation of Gli1 to upregulate expression of genes associated with cellular proliferation and migration. Intriguingly, blockage of Shh/Gli1 signaling with cyclopamine reversed the promoting effects of LAMA4 on proliferation and migration of fibroblasts. Conclusions: LAMA4 positively regulated cellular proliferation and migration in fibroblasts via activating the Shh/Gli1 signaling. LAMA4/Shh/Gli1 signaling axis might be a potential therapeutic target for the prevention of surgery-induced intraarticular fibrosis.

Artesunate alleviates diabetic retinopathy by activating autophagy via the regulation of AMPK/SIRT1 pathway

CONTEXT

Artesunate (ART), an antimalarial drug, possesses the ability to induce autophagy and exhibits a protective effect on diabetes.

OBJECTIVE

This study aimed to evaluate the effects of ART on diabetic retinopathy (DR) and to explore the underlying mechanisms.

METHODS

Rats with streptozotocin-induced DR were given intravitreal injection of ART.

RESULTS

ART administration inhibited the increase in retinal thickness and prevented blood-retinal barrier in diabetic rats. Further, vascular leukocyte adherence, microglial activation, inflammatory cytokine, and ROS production in the retinas of diabetic rats were also inhibited by ART. Additionally, ART enhanced autophagy in the retinas of diabetic rats as demonstrated by up-regulated Beclin-1 expression and LC3II/I ratio and down-regulated p62. ART also activated AMP-activated protein kinase (AMPK)/sensor class III histone deacetylase sirtuin 1 (SIRT1) pathway.

CONCLUSIONS

ART, as an autophagy activator, has therapeutic potential in DR treatment.

Artemisinin and artemisinin derivatives as anti-fibrotic therapeutics

Fibrosis is a pathological reparative process that can occur in most organs and is responsible for nearly half of deaths in the developed world. Despite considerable research, few therapies have proven effective and been approved clinically for treatment of fibrosis. Artemisinin compounds are best known as antimalarial therapeutics, but they also demonstrate antiparasitic, antibacterial, anticancer, and anti-fibrotic effects. Here we summarize literature describing anti-fibrotic effects of artemisinin compounds in in vivo and in vitro models of tissue fibrosis, and we describe the likely mechanisms by which artemisinin compounds appear to inhibit cellular and tissue processes that lead to fibrosis. To consider alternative routes of administration of artemisinin for treatment of internal organ fibrosis, we also discuss the potential for more direct oral delivery of Artemisia plant material to enhance bioavailability and efficacy of artemisinin compared to administration of purified artemisinin drugs at comparable doses. It is our hope that greater understanding of the broad anti-fibrotic effects of artemisinin drugs will enable and promote their use as therapeutics for treatment of fibrotic diseases.

Prenatal dexamethasone exposure caused fetal rats liver dysplasia by inhibiting autophagy-mediated cell proliferation

As a synthetic glucocorticoid, dexamethasone has been widely used in the clinical treatment of premature birth and related pregnant diseases, but its clinical use is still controversial due to developmental toxicity. This study aimed to confirm the proliferation inhibitory effect of pregnant dexamethasone exposure (PDE) on fetal liver development and elucidate its molecular mechanism. In vitro studies, we found that dexamethasone inhibited hepatocyte proliferation through autophagy activated by glucocorticoid receptor (GR)-forkhead protein O1 (FOXO1) pathway. Subsequently, in vivo, we confirmed in a PDE rat model that male fetal liver proliferation was inhibited, and the expression of the GR-FOXO1 pathway and autophagy were increased. Taken together, PDE induces autophagy by activating the GR-FOXO1 pathway, which leads to fetal liver proliferation inhibition and dysplasia in offspring rats. This study confirmed that dexamethasone activates cell autophagy in utero through the GR-FOXO1 pathway, thereby inhibiting hepatocyte proliferation and liver development, which provides theoretical basis for understanding the developmental toxicity of dexamethasone and guiding the rational clinical use.

Artesunate Impairs Growth in Cisplatin-Resistant Bladder Cancer Cells by Cell Cycle Arrest, Apoptosis and Autophagy Induction

Cisplatin, which induces DNA damage, is standard chemotherapy for advanced bladder cancer (BCa). However, efficacy is limited due to resistance development. Since artesunate (ART), a derivative of artemisinin originating from Traditional Chinese Medicine, has been shown to exhibit anti-tumor activity, and to inhibit DNA damage repair, the impact of artesunate on cisplatin-resistant BCa was evaluated. Cisplatin-sensitive (parental) and cisplatin-resistant BCa cells, RT4, RT112, T24, and TCCSup, were treated with ART (1-100 µM). Cell growth, proliferation, and cell cycle phases were investigated, as were apoptosis, necrosis, ferroptosis, autophagy, metabolic activity, and protein expression. Exposure to ART induced a time- and dose-dependent significant inhibition of tumor cell growth and proliferation of parental and cisplatin-resistant BCa cells. This inhibition was accompanied by a G0/G1 phase arrest and modulation of cell cycle regulating proteins. ART induced apoptos is by enhancing DNA damage, especially in the resistant cells. ART did not induce ferroptosis, but led to a disturbance of mitochondrial respiration and ATP generation. This impairment correlated with autophagy accompanied by a decrease in LC3B-I and an increase in LC3B-II. Since ART significantly inhibits proliferative and metabolic aspects of cisplatin-sensitive and cisplatin-resistant BCa cells, it may hold potential in treating advanced and therapy-resistant BCa.

NUCKS promotes cell proliferation and suppresses autophagy through the mTOR-Beclin1 pathway in gastric cancer

Background

Nuclear casein kinase and cyclin-dependent kinase substrate (NUCKS), a novel gene first reported in 2001, is a member of the high mobility group (HMG) family. Although very little is known regarding the biological roles of NUCKS, emerging clinical evidence suggests that the NUCKS protein can be used as a biomarker and therapeutic target in various human ailments, including several types of cancer.

Methods

We first assessed the potential correlation between NUCKS expression and gastric cancer prognosis. Then functional experiments were conducted to evaluate the effects of NUCKS in cell proliferation, cell cycle, apoptosis and autophagy. Finally, the roles of NUCKS on gastric cancer were examined in vivo.

Results

We found that NUCKS was overexpressed in gastric cancer patients with poor prognosis. Through manipulating NUCKS expression, it was observed to be positively associated with cell proliferation in vitro and in vivo. NUCKS knockdown could induce cell cycle arrest and apoptosis. Then further investigation indicated that NUCKS knockdown could also significantly induce a marked increase in autophagy though the mTOR-Beclin1 pathway, which could be was rescued by NUCKS restoration. Moreover, silencing Beclin1 in NUCKS knockdown cells or adding rapamycin in NUCKS-overexpressed cells also confirmed these results.

Conclusions

Our findings revealed that NUCKS functions as an oncogene and an inhibitor of autophagy in gastric cancer. Thus, the downregulation or inhibition of NUCKS may be a potential therapeutic strategy for gastric cancer.

Artesunate reverses LPS tolerance by promoting ULK1-mediated autophagy through interference with the CaMKII-IP3R-CaMKKβ pathway

The progress of sepsis is increasingly recognized by the transition from early hyperinflammation to long term immunosuppression, which is characterized in innate immune cells by diminished responsiveness termed as lipopolysaccharide (LPS) tolerance. In this study, we investigated the ability of the antimalarial drug artesunate to reverse LPS tolerance and explored the underlying mechanisms. Initially, we detected a dramatic decline in autophagy accompanied by decreased cytokine production and impaired bacterial clearance by LPS tolerant macrophages. Then we demonstrated that artesunate restored cytokine production and enhanced bacterial clearance by inducing autophagy. Moreover, artesunate caused greater suppression of inhibitory phosphorylation than of activating phosphorylation of Unc-51 like autophagy activating kinase 1 (ULK1), a kinase that is essential for initiating autophagy through the inhibition of excessive AMP-activated protein kinase (AMPK) activation. This effect was shown to be achieved by suppression of Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) phosphorylation, resulting in reduction of the inositol 1,4,5-triphate receptor (IP3R) dependent Ca²⁺ release from the endoplasmic reticulum (ER) and inhibiting the overactive CaMKKβ-AMPK cascade. Administration of artesunate also upregulated autophagy and reversed the tolerant status in LPS tolerant mice. In summary, our findings reveal a novel immunopharmacological action of artesunate to reverse LPS tolerance by restoring autophagy. Our results may also indicate the significance of autophagy induction for treating immunosuppression in sepsis.

The combination of artesunate and carboplatin exerts a synergistic anti-tumour effect on non-small cell lung cancer

Carboplatin (CBP) is a widely used targeted anticancer therapeutic drug; however, multi-drug resistance induced by the accumulation of CBP eventually causes diseases progression. The anti-malarial drug artesunate (ART) also exerts anticancer effects in various cancers; however, the combined effect of ART and CBP on non-small cell lung cancer (NSCLC) remains unclear. In the present study, the NSCLC cell line A549 was pretreated with various concentrations of CBP, ART and gemcitabine (GEM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were conducted to detect cell viability. Cell apoptosis was evaluated by both flow cytometry and TUNEL apoptotic assay. The expression profiles of cell cycle-related proteins and apoptotic proteins were determined by western blot. Cell clone numbers were visualized using crystal violet staining. Here, we found that both CBP and ART suppressed cell viability, and promoted cell apoptosis, and the combined application of ART and CBP at a lower concentration exhibited synergistic effects. Specifically, the combination of ART and CBP at a lower concentration suppressed cell clone numbers, promoted cell cycle arrest at the G₂ /M phase, and induced the expression of the cell cycle and apoptosis-related proteins BAX, p21, p53, and Caspase-3, while decreasing Bcl-2 and Cyclin B1 expression. Based on these results, we concluded that combined application of ART and CBP exerts synergistic anti-tumour effects on NSCLC by enhancing cell apoptosis in a mitochondria-dependent manner.