Curcumin relieved cisplatin-induced kidney inflammation through inhibiting Mincle-maintained M1 macrophage phenotype

Baicalein alleviates cisplatin-induced acute kidney injury by inhibiting ALOX12-dependent ferroptosis

BACKGROUND

In acute kidney injury (AKI), ferroptosis is the main mechanism of cell death in the renal tubular epithelium. Baicalein, a traditional Chinese medicine monomer, plays a protective role in various kidney diseases; however, the effect of baicalein on ferroptosis in AKI still needs further exploration.

PURPOSE

In this study, we explored the role of baicalein and its specific mechanism in mediating ferroptosis in cisplatin-induced AKI.

METHODS

We used a cisplatin-induced AKI model to study the effects of baicalein on renal tissue and tubular epithelial cell injury. The effects of baicalein on tubular epithelial cell ferroptosis were detected in cisplatin-induced AKI and further verified by folic acid-induced AKI. The Swiss Target Prediction online database was used to predict the possible mechanism by which baicalein regulates ferroptosis, and the specific target proteins were further verified. Molecular docking and SPR were used to further determine the binding potential of baicalein to the target protein. Finally, RNA interference (RNAi) technology and enzymatic inhibition were used to determine whether baicalein regulates ferroptosis through target proteins.

RESULTS

Baicalein alleviated cisplatin- and folic acid-induced renal dysfunction and pathological damage and improved cisplatin-induced HK2 cell injury. Mechanistically, baicalein reduced the expression of 12-lipoxygenase (ALOX12), which inhibits phospholipid peroxidation and ferroptosis in AKI. Molecular docking and SPR demonstrated direct binding between baicalein and ALOX12. Finally, we found that silencing ALOX12 had a regulatory effect similar to that of baicalein. Comparable results were also obtained with the ALOX12 inhibitor ML355.

CONCLUSION

This was the first study to confirm that baicalein regulates ferroptosis both in vitro and in vivo in cisplatin-induced AKI and to verify the regulatory effect of baicalein in folic acid-induced AKI. Our results reveal the critical role of ALOX12 in kidney damage and ferroptosis caused by cisplatin and emphasize the regulatory effect of baicalein on renal tubular epithelial cell ferroptosis mediated by ALOX12. Baicalein is an effective drug for treating AKI, and ALOX12 is a potential drug target.

Polymeric scaffold integrated with nanovesicle-entrapped curcuminoids for enhanced therapeutic efficacy

Aim: Polymeric scaffolds were developed fortified with nanovesicle-encapsulated individual curcumin (CUR) and tetrahydrocurcumin (THC) for improved therapeutic efficacy due to their low stability and efficacy in native form. Method: Nanovesicle-encapsulated individual CUR and THC were fabricated using thin-film hydration techniques and characterized. Results & conclusion: CUR/THC in native and vesicle-encapsulated form demonstrated diminished LPS-instigate nitric oxide (NO) levels in macrophage cells in a concentration-dependent demeanor. However, vesicle-encapsulated CUR/THC inhibited NO production at lower concentrations, compared with the native CUR/THC form. Furthermore, the scaffold fortified with vesicle-encapsulated CUR/THC demonstrated improved physical properties with excellent antioxidant, biocompatibility, and human keratinocyte cell proliferation ability. The results recommended that nanovesicle-encapsulated THC can be retained as a potential substitute for CUR with improved therapeutic efficacy.

Natural Products with Potential Effects on Hemorrhoids: A Review

Hemorrhoid disease is a common anorectal disorder affecting populations worldwide, with high prevalence, treatment difficulties, and considerable treatment costs. Compared to other treatment options, medical therapy for hemorrhoids offers minimal harm, more dignity to patients, and is more economical. Unfortunately, there are few chemical hemorrhoid medications available clinically, which makes the search for efficacious, cost-effective, and environmentally friendly new medication classes a focal point of research. In this context, searching for available natural products to improve hemorrhoids exhibits tremendous potential. These products are derived from nature, predominantly from plants, with a minor portion coming from animals, fungi, and algae. They have excellent coagulation pathway regulation, anti-inflammatory, antibacterial, and tissue regeneration activities. Therefore, we take the view that they are a class of potential hemorrhoid drugs, prevention products, and medication add-on ingredients. This article first reviews the factors contributing to the development of hemorrhoids, types, primary symptoms, and the mechanisms of natural products for hemorrhoids. Building on this foundation, we screened natural products with potential hemorrhoid improvement activity, including polyphenols and flavonoids, terpenes, polysaccharides, and other types.

Role of miRNAs in macrophage-mediated kidney injury

Macrophages, crucial components of the human immune system, can be polarized into M1/M2 phenotypes, each with distinct functions and roles. Macrophage polarization has been reported to be significantly involved in the inflammation and fibrosis observed in kidney injury. MicroRNA (miRNA), a type of short RNA lacking protein-coding function, can inhibit specific mRNA by partially binding to its target mRNA. The intricate association between miRNAs and macrophages has been attracting increasing interest in recent years. This review discusses the role of miRNAs in regulating macrophage-mediated kidney injury. It shows how miRNAs can influence macrophage polarization, thereby altering the biological function of macrophages in the kidney. Furthermore, this review highlights the significance of miRNAs derived from exosomes and extracellular vesicles as a crucial mediator in the crosstalk between macrophages and kidney cells. The potential of miRNAs as treatment applications and biomarkers for macrophage-mediated kidney injury is also discussed.

Therapeutic detoxification of quercetin for aflatoxin B1-related toxicity: Roles of oxidative stress, inflammation, and metabolic enzymes

Aflatoxins (AFTs), a type of mycotoxin mainly produced by Aspergillus parasiticus and Aspergillus flavus, could be detected in food, feed, Chinese herbal medicine, grain crops and poses a great threat to public health security. Among them, aflatoxin B1 (AFB1) is the most toxic one. Exposure to AFB1 poses various health risks to both humans and animals, including the development of chronic inflammatory diseases, cardiovascular diseases, neurodegenerative diseases, and cancer. The molecular mechanisms underlying these risks are intricate and dependent on specific contexts. This review primarily focuses on summarizing the protective effects of quercetin, a natural phenolic compound, in mitigating the toxic effects induced by AFB1 in both in vitro experiments and animal models. Additionally, the review explores the molecular mechanisms that underlie these protective effects. Quercetin has been demonstrated to not only have the direct inhibitory action on the production of AFTs from Aspergillus, both also possess potent ameliorative effects against AFB1-induced cytotoxicity, hepatotoxicity, and neurotoxicity. These effects are attributed to the inhibition of oxidative stress, mitochondrial dysfunction, mitochondrial apoptotic pathway, and inflammatory response. It could also directly target several metabolic enzymes (i.e., CYP3As and GSTA1) to reduce the production of toxic metabolites of AFB1 within cells, then reduce AFB1-induced cytotoxicity. In conclusion, this review highlights quercetin is a promising detoxification agent for AFB1. By advancing our understanding of the protective mechanisms offered by quercetin, we aim to contribute to the development of effective detoxification agents against AFB1, ultimately promoting better health outcomes.

SAP130 released by ferroptosis tubular epithelial cells promotes macrophage polarization via Mincle signaling in sepsis acute kidney injury

The pathological mechanism of sepsis-associated acute kidney injury (SA-AKI) is complex and involves tubular epithelial cell (TEC) death and immune cell activation. However, the interaction between tubular cell death and macrophage-mediated inflammation remains unclear. In this study, we uncovered that TEC ferroptosis was activated in SA-AKI. Increased levels of ferroptotic markers, including ferroptosis-related proteins, lipid peroxidation, malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), reactive oxygen species (ROS), and mitochondrial damage, were observed in the kidney tissue of cecum ligation and puncture (CLP) and Lipopolysaccharide (LPS)-induced SA-AKI mouse models, which were subsequently suppressed by Ferrostatin-1 (Fer-1). In vitro experiments showed that Fer-1 inhibits LPS-induced mitochondrial damage, Fe2+ accumulation, and cytosolic ROS production. Moreover, it was found that TEC ferroptosis induced by promoted macrophage-inducible C-type lectin (Mincle) and its downstream expression and M1 polarization, which was mediated by the release of spliceosome-associated protein 130 (SAP130), an endogenous ligand of Mincle, from TEC. It was confirmed in vitro that the supernatant from LPS-stimulated TECs promoted Mincle expression and M1 polarization in macrophages. Further experiments revealed that M1 macrophages aggravated TEC ferroptosis, which was offset by neutralizing SAP130 or inhibiting Mincle expression. In addition, neutralizing the circulatory SAP130 blunted kidney ferroptosis and Mincle expression, as well as macrophage infiltration in the kidney of SA-AKI mice. In conclusion, the release of SAP130 from ferroptotic TECs promoted M1 macrophage polarization by triggering Mincle/syk/NF-κB signaling, and M1 macrophages, in turn, aggravated TEC ferroptosis.

Role of renal tubular epithelial cells and macrophages in cisplatin-induced acute renal injury

Acute kidney injury (AKI) is a clinical syndrome characterized by a sudden and continuous decline in renal function. The drug cisplatin is commonly used as chemotherapy for solid tumors, and cisplatin-induced acute kidney injury (CI-AKI), which is characterized by acute tubular necrosis and inflammation, frequently occurs in tumor patients. Renal tubular epithelial cells (RTECs) are severely damaged early in this process and play an important role in renal tubular injury and the recruitment of immune cells. Macrophages are the most common infiltrating immune cells in the kidney and have a significant impact on CI-AKI and subsequent repair. This article reviews the latest research progress on the effects of RTECs and macrophages on CI-AKI and their interactions in AKI to provide a direction for identifying therapeutic targets for treating AKI.

Role of epigenetically regulated inflammation in renal diseases

In recent decades, renal disease research has witnessed remarkable advances. Experimental evidence in this field has highlighted the role of inflammation in kidney disease. Epigenetic dynamics and immunometabolic reprogramming underlie the alterations in cellular responses to intrinsic and extrinsic stimuli; these factors determine cell identity and cell fate decisions and represent current research hotspots. This review focuses on recent findings and emerging concepts in epigenetics and inflammatory regulation and their effect on renal diseases. This review aims to summarize the role and mechanisms of different epigenetic modifications in renal inflammation and injury and provide new avenues for future research on inflammation-related renal disease and drug development.

Hyperoside ameliorates cisplatin-induced acute kidney injury by regulating the expression and function of Oat1

Cisplatin is a widely used chemotherapeutic agent to treat solid tumours in clinics. However, cisplatin-induced acute kidney injury (AKI) limits its clinical application. This study investigated the effect of hyperoside (a flavonol glycoside compound) on regulating AKI.The model of cisplatin-induced AKI was established, and hyperoside was preadministered to investigate its effect on improving kidney injury.Hyperoside ameliorated renal pathological damage, reduced the accumulation of SCr, BUN, Kim-1 and indoxyl sulphate in vivo, increased the excretion of indoxyl sulphate into the urine, and upregulated the expression of renal organic anion transporter 1 (Oat1). Moreover, evaluation of rat kidney slices demonstrated that hyperoside promoted the uptake of PAH (p-aminohippurate, the Oat1 substrate), which was confirmed by transient over-expression of OAT1 in HEK-293T cells. Additionally, hyperoside upregulated the mRNA expression of Oat1 upstream regulators hepatocyte nuclear factor-1α (HNF-1α) and pregnane X receptor (PXR).These findings indicated hyperoside could protect against cisplatin-induced AKI by promoting indoxyl sulphate excretion through regulating the expression and function of Oat1, suggesting hyperoside may offer a potential tactic for cisplatin-induced AKI treatment.

Mammary Epithelial Cell-Derived Exosomal miR-221-3p Regulates Macrophage Polarization by Targeting Igf2bp2 during Mastitis

Mastitis affects the milk quality and yield and is the most expensive disease in dairy cows. Elucidation of the pathogenesis of mastitis is of great importance for disease control. As a medium of intercellular communication, exosomes play key roles in various inflammatory diseases by regulating macrophage polarization. However, the molecular factors in exosomes that mediate the intercellular communication between mammary epithelial cells and macrophages during mastitis remain to be further explored. In this study, we isolated and identified mammary epithelial cell-derived exosomes from a lipopolysaccharide (LPS)/lipoteichoic acid (LTA)-induced mastitis cell model, and we demonstrated that exosomes from LPS/LTA-stimulated mammary epithelial cells promote M1-type macrophage polarization in vivo and in vitro. Based on the results of high-throughput sequencing, we constructed a differential miRNA (microRNA) expression profile of exosomes and demonstrated that miR-221-3p was highly expressed. Furthermore, in vivo and in vitro experiments, combined with coculture experiments and fluorescence tracing, showed that high miR-221-3p expression promoted M1-type macrophage polarization, demonstrating the transcellular role of miR-221-3p. Mechanistically, dual luciferase reporter gene assays and rescue assays showed that miR-221-3p regulated macrophage polarization by targeting Igf2bp2. The results of this study will deepen our understanding of the pathogenesis of mastitis, and the molecular regulatory axis that was established in this study is expected to be a target for mastitis treatment.

Microbe-host interactions: structure and functions of Gram-negative bacterial membrane vesicles

Bacteria-host interaction is a common, relevant, and intriguing biological phenomena. The host reacts actively or passively to the bacteria themselves, their products, debris, and so on, through various defense systems containing the immune system, the bacteria communicate with the local or distal tissues of the host via their own surface antigens, secreted products, nucleic acids, etc., resulting in relationships of attack and defense, adaptation, symbiosis, and even collaboration. The significance of bacterial membrane vesicles (MVs) as a powerful vehicle for the crosstalk mechanism between the two is growing. In the recent decade, the emergence of MVs in microbial interactions and a variety of bacterial infections, with multiple adhesions to host tissues, cell invasion and evasion of host defense mechanisms, have brought MVs to the forefront of bacterial pathogenesis research. Whereas MVs are a complex combination of molecules not yet fully understood, research into its effects, targeting and pathogenic components will advance its understanding and utilization. This review will summarize structural, extraction and penetration information on several classes of MVs and emphasize the role of MVs in transport and immune response activation. Finally, the potential of MVs as a therapeutic method will be highlighted, as will future research prospects.

Leonotis ocymifolia (Burm.f.) Iwarsson aerial parts aqueous extract mitigates cisplatin-induced nephrotoxicity via attenuation of inflammation, and DNA damage

Herein, we explored the protective effect of Leonotis ocymifolia (Burm.f.) Iwarsson aerial parts extract (LO) against cisplatin (CP)-induced nephrotoxicity in rats and profiled their phytocontents. A total of 31 compounds belonging to organic and phenolic acids and their glycosides as well as flavonoids and their O- and C-glycosides were identified through LC-MS/MS. The DPPH and FRAP assays revealed that the extract had powerful antioxidant properties. The in vivo results demonstrated that administering LO extract for 30 days (40 and 80 mg/kg b. w.) significantly improved the altered renal injury markers via reducing creatinine (high dose only) and uric acid levels compared to the Cp-group. The deleterious action of cisplatin on renal oxidative stress markers (GSH, MDA, SOD, and CAT) were also mitigated by LO-pretreatment. The reduction of the inflammatory marker (IL-6), and inhibition of DNA fragmentation, highlighted the prophylactic action of LO in kidney tissue. Molecular docking followed by a 100 ns molecular dynamic simulation analyses revealed that, amongst the 31 identified compounds in LO, chlorogenic and caffeoylmalic acids had the most stable binding to IL-6. The nephroprotective effects were further confirmed by histopathological observations, which showed improvement in ultrastructural changes induced by cisplatin. The observed findings reinforce the conclusion that L. ocymifolia extract exerts nephroprotective properties, which could be related to its antioxidant and anti-inflammatory activities. Further studies are required to determine the therapeutic doses and the proper administration time.

Preparation, characterization and protective effect of chitosan - Tripolyphosphate encapsulated dihydromyricetin nanoparticles on acute kidney injury caused by cisplatin

Dihydromyricetin (DMY) is a natural dihydroflavonol compound known for its diverse pharmacological benefits. However, its limited stability and bioavailability posed significant challenges for further applications. To address these issues, in this study, an ion crosslinking method was utilized to prepare chitosan nanoparticles that were loaded with DMY. The synthesized chitosan nanoparticles (CS-DMY-NPs) were spherical in shape with particle size and ζ potential of 198.7 nm and 45.05 mV, respectively. Furthermore, in vitro release experiments demonstrated that CS-DMY-NPs had sustained release and protective effects in simulated gastric and intestinal fluids. CS-DMY-NPs exhibited better antioxidant activity by ABTS and DPPH radical scavenging activity than free DMY. In vivo study showed that CS-DMY-NPs alleviated cisplatin-induced kidney damage by inhibiting oxidative stress and proinflammatory cytokines, and had better activity compared to DMY (free). Immunofluorescence data showed that CS-DMY-NPs activated the Nrf2 signaling pathways in a dose-dependent manner to combat cisplatin-induced kidney damage. Our results demonstrate that CS-TPP has good compatibility with DMY, and CS-DMY-NPs exhibited better protective effects against cisplatin-induced acute kidney injury (AKI) than free DMY.

The role of the SGK3/TOPK signaling pathway in the transition from acute kidney injury to chronic kidney disease

Introduction: Profibrotic phenotype of renal tubular epithelial cells (TECs) featured with epithelial to mesenchymal transition (EMT) and profibrotic factors secretion, and aberrant accumulation of CD206⁺ M2 macrophages are the key points in the transition from acute kidney injury (AKI) to chronic kidney disease (CKD). Nevertheless, the underlying mechanisms involved remain incompletely understood. Serum and glucocorticoid-inducible kinase (SGK) is a serine/threonine protein kinase, required for intestinal nutrient transport and ion channels modulation. T-LAK-cell-originated protein kinase (TOPK) is a member of the mitogen activated protein kinase family, linked to cell cycle regulation. However, little is known about their roles in AKI-CKD transition. Methods: In this study, three models were constructed in C57BL/6 mice: low dose and multiple intraperitoneal injection of cisplatin, 5/6 nephrectomy and unilateral ureteral obstruction model. Rat renal tubular epithelial cells (NRK-52E) were dealt with cisplatin to induce profibrotic phenotype, while a mouse monocytic cell line (RAW264.7) were cultured with cisplatin or TGF-β1 to induce M1 or M2 macrophage polarization respectively. And co-cultured NRK-52E and RAW264.7 through transwell plate to explore the interaction between them. The expression of SGK3 and TOPK phosphorylation were detected by immunohistochemistry, immunofluorescence and western blot analysis. Results: In vivo, the expression of SGK3 and p-TOPK were gradually inhibited in TECs, but enhanced in CD206⁺ M2 macrophages. In vitro, SGK3 inhibition aggravated epithelial to mesenchymal transition through reducing the phosphorylation state of TOPK, and controlling TGF-β1 synthesis and secretion in TECs. However, SGK3/TOPK axis activation promoted CD206⁺ M2 macrophage polarization, which caused kidney fibrosis by mediating macrophage to myofibroblast transition (MMT). When co-cultured, the TGF-β1 from profibrotic TECs evoked CD206⁺ M2 macrophage polarization and MMT, which could be attenuated by SGK3/TOPK axis inhibition in macrophages. Conversely, SGK3/TOPK signaling pathway activation in TECs could reverse CD206⁺ M2 macrophages aggravated EMT. Discussion: We revealed for the first time that SGK3 regulated TOPK phosphorylation to mediate TECs profibrotic phenotype, macrophage plasticity and the crosstalk between TECs and macrophages during AKI-CKD transition. Our results demonstrated the inverse effect of SGK3/TOPK signaling pathway in profibrotic TECs and CD206⁺ M2 macrophages polarization during the AKI-CKD transition.

Potential therapeutic effects of Chinese meteria medica in mitigating drug-induced acute kidney injury

Drug-induced acute kidney injury (DI-AKI) is one of the leading causes of kidney injury, is associated with high mortality and morbidity, and limits the clinical use of certain therapeutic or diagnostic agents, such as antineoplastic drugs, antibiotics, immunosuppressants, non-steroidal anti-inflammatory drugs, and contrast media. In recent years, numerous studies have shown that many Chinese meteria medica, metabolites derived from botanical drugs, and Chinese medicinal formulas confer protective effects against DI-AKI by targeting a variety of cellular or molecular mechanisms, such as oxidative stress, inflammatory, cell necrosis, apoptosis, and autophagy. This review summarizes the research status of common DI-AKI with Chinese meteria medica interventions, including cisplatin, gentamicin, contrast agents, methotrexate, and acetaminophen. At the same time, this review introduces the metabolites with application prospects represented by ginseng saponins, tetramethylpyrazine, panax notoginseng saponins, and curcumin. Overall, this review provides a reference for the development of promising nephroprotectants.

The role of metabolic reprogramming of oxygen-induced macrophages in the dynamic changes of atherosclerotic plaques

Atherosclerosis (As) is a chronic vascular inflammatory disease. Macrophages are the most important immune cells in atherosclerotic plaques, and the phenotype of plaque macrophages shifts dynamically to adapt to changes in the plaque microenvironment. The aerobic microenvironment of early atherosclerotic plaques promotes the transformation of M2/alternatively activated macrophages mainly through oxidative phosphorylation; the anoxic microenvironment of advanced atherosclerotic plaques mainly promotes the formation of M1/classically activated macrophages through anaerobic glycolysis; and the adventitia angiogenesis of aged atherosclerotic plaques leads to an increase in the proportion of M2/M1 macrophages. Therefore, this review deeply elucidates the dynamic change mechanism of plaque macrophages and the regulation of plaque oxygen content and immune metabolism to find new targets for the treatment of As.

The Development of Dyslipidemia in Chronic Kidney Disease and Associated Cardiovascular Damage, and the Protective Effects of Curcuminoids

Chronic kidney disease (CKD) is a health problem that is constantly growing. This disease presents a diverse symptomatology that implies complex therapeutic management. One of its characteristic symptoms is dyslipidemia, which becomes a risk factor for developing cardiovascular diseases and increases the mortality of CKD patients. Various drugs, particularly those used for dyslipidemia, consumed in the course of CKD lead to side effects that delay the patient's recovery. Therefore, it is necessary to implement new therapies with natural compounds, such as curcuminoids (derived from the Curcuma longa plant), which can cushion the damage caused by the excessive use of medications. This manuscript aims to review the current evidence on the use of curcuminoids on dyslipidemia in CKD and CKD-induced cardiovascular disease (CVD). We first described oxidative stress, inflammation, fibrosis, and metabolic reprogramming as factors that induce dyslipidemia in CKD and their association with CVD development. We proposed the potential use of curcuminoids in CKD and their utilization in clinics to treat CKD-dyslipidemia.

Research progress on Mincle as a multifunctional receptor

Macrophage-induced C-type lectin (Mincle), a lipopolysaccharide-induced protein, is widely expressed on antigen-presenting cells. Mincle acts as a pattern recognition receptor that recognizes pathogen-associated molecular patterns of pathogens such as bacteria and fungi, mainly glycolipids, which induces an acquired immune response against microbial infection. Interestingly, Mincle can also identify patterns of lipid damage-associated molecule patterns released by injured cells, such as Sin3-associated protein 130 and β-glucosylceramides, which induces sterile inflammation and ultimately accelerates the progression of stroke, obesity, hepatitis, kidney injury, autoimmune diseases and tumors by promoting tissue inflammation. This article will review the various functions of Mincle, such as mediating sterile inflammation of tissues to accelerate disease progression, initiating immune responses to fight infection and promoting tumor progression.

Macrophage-derived exosomal miR-195a-5p impairs tubular epithelial cells mitochondria in acute kidney injury mice

Macrophages (Mφ) infiltration is a common characteristic of acute kidney injury (AKI). Exosomes-mediated cell communication between tubular epithelial cells (TECs) and Mφ has been suggested to be involved in AKI. Exosomes-derived from injured TECs could regulate Mφ polarization during AKI. However, little is known regarding how activated Mφ regulates kidney injury. To explore the role of activated Mφ in the AKI process, we revealed that Mφ-derived exosomes from AKI mice (Exos^AKI ) caused mitochondria damage and induced TECs injury. Then, we detected the global miRNA expression profiles of Mφ^NC and Mφ^AKI and found that among the upregulated miRNAs, miR-195a-5p, which regulates mitochondria metabolism in cancer, was significantly increased in Mφ^AKI . Due to the enrichment of miR-195a-5p in Exos^AKI , the miR-195a-5p level in the kidney was elevated in AKI mice. More interestingly, based on the high expression of pri-miR-195a-5p in kidney-infiltrated Mφ, and the reduction of miR-195a-5p in kidney after depletion of Mφ in AKI mice, we confirmed that miR-195a-5p may be produced in infiltrated Mφ, and shuttled into TECs via Exos^Mφ . Furthermore, in vitro inhibition of miR-195a-5p alleviated the effect of Exos^AKI induced mitochondrial dysfunction and cell injury. Consistently, antagonizing miR-195a-5p with a miR-195a-5p antagomir attenuated cisplatin-induced kidney injury and mitochondrial dysfunction in mice. These findings revealed that the Mφ exosomal miR-195a-5p derived from AKI mice played a critical pathologic role in AKI progression, representing a new therapeutic target for AKI.

Curcumin Improves Diabetic Cardiomyopathy by Inhibiting Pyroptosis through AKT/Nrf2/ARE Pathway

This study is aimed at exploring whether curcumin can regulate the AKT pathway, promote the transfer of Nrf2 into the nucleus, and inhibit cell pyroptosis in diabetic cardiomyopathy. Diabetic rats and cardiomyocytes were treated with curcumin to study its effect on myocardial pyroptosis. Whether curcumin can promote the transfer of Nrf2 into the nucleus through AKT pathway regulation was assessed by western blotting and immunofluorescence. The Nrf2 knockout vector and ml385 were used to block the Nrf2 pathway, and the differences between the different groups in the expression of pyroptosis protein, cell activity, and incidence of apoptosis were evaluated to verify the relationship between the effect of curcumin on pyroptosis inhibition and the Nrf2 pathway. Curcumin promoted the transfer of Nrf2 into the nucleus through the AKT pathway and increased the expression of the antioxidant factors HO-1 and GCLC. These effects reduced reactive oxygen species accumulation and mitochondrial damage in diabetic myocardium and inhibited diabetes-induced pyroptosis. However, in cardiomyocytes with a blocked Nrf2 pathway, the ability of curcumin to inhibit pyroptosis was significantly reduced, and the protective effect on the cells was lost. Curcumin can reduce the accumulation of superoxide in the myocardium through AKT/Nrf2/ARE pathway activation and inhibit pyroptosis. It also has a role in diabetic cardiomyopathy treatment. This study provides new directions for evaluating the mechanism of diabetic cardiomyopathy and treating diabetic myocardium.

Astragaloside IV Targets Macrophages to Alleviate Renal Ischemia-Reperfusion Injury via the Crosstalk between Hif-1α and NF-κB (p65)/Smad7 Pathways

(1) Background: Astragaloside IV (AS-IV) is derived from Astragalus membranous (AM), which is used to treat kidney disease. Macrophages significantly affect the whole process of renal ischemia-reperfusion (I/R). The regulation of macrophage polarization in kidneys by AS-IV was the focus. (2) Methods: Renal tubular injury and fibrosis in mice were detected by Hematoxylin and Eosin staining and Masson Trichrome Staining, separately. An ELISA and quantitative real-time polymerase chain reaction were used to explore the cytokine and mRNA expression. Western blot was used to determine protein expression and siRNA technology was used to reveal the crosstalk of signal pathways in RAW 264.7 under hypoxia. (3) Results: In the early stages of I/R injury, AS-IV reduced renal damage and macrophage infiltration. M1-associated markers were decreased, while M2 biomarkers were increased. The NF-κB (p65)/Hif-1α pathway was suppressed by AS-IV in M1. Moreover, p65 dominated the expression of Hif-1α. In the late stages of I/R injury, renal fibrosis was alleviated, and M2 infiltration also decreased after AS-IV treatment. Hif-1α expression was reduced by AS-IV, while Smad7 expression was enhanced. Hif-1α interferes with the expression of Smad7 in M2. (4) Conclusions: AS-IV promoted the differentiation of M1 to M2, relieving the proinflammatory response to alleviate the kidney injury during the early stages. AS-IV attenuated M2 macrophage infiltration to prevent kidney fibrosis during the later stages.

Low curcumin concentrations combined with blue light inhibits cutibacterium acnes biofilm-induced inflammatory response through suppressing MAPK and NF-κB in keratinocytes

BACKGROUND

Curcumin has been employed as a photosensitizer agent during photodynamic therapy (PDT). Cutibacterium acnes (C. acnes) can cause an inflammatory response in human keratinocytes; however, no research has been conducted to determine whether curcumin and its photodynamic properties can prevent this inflammatory reaction.

OBJECTIVE

We hypothesized that curcumin may control the C. acnes biofilm-induced inflammatory response in keratinocytes, either alone or in combination with blue light photodynamic therapy.

METHODS

Following C. acnes biofilm stimulation, human primary keratinocytes were treated with 20 μM curcumin solution alone or 5 μM curcumin with combined blue light irradiation. The amount of secreted protein was measured using an ELISA kit. The expression levels of Toll-like receptor 2 (TLR2) and its downstream proteins were determined using western blot.

RESULTS

Treatment with 20 μM curcumin, but not 5 μM curcumin, reduced the inflammatory response to C. acnes biofilms in keratinocytes by blocking the TLR2/MAPK/NF-κB pathway. Interestingly, 5 μM curcumin combined with blue light also reduced the C. acnes biofilm-induced inflammation indicated above by blocking the TLR2/MAPK/NF-κB pathway.

CONCLUSION

Curcumin alone, in sufficient concentrations, or low-concentration curcumin with blue light had anti-inflammatory activity on keratinocytes stimulated by C. acnes biofilms through inhibition of MAPK and NF-κB signaling pathways by downregulating TLR2 expression.

Curcumin-Nicotinate Attenuates Hippocampal Synaptogenesis Dysfunction in Hyperlipidemia Rats by the BDNF/TrkB/CREB Pathway: Involving Idol/LDLR Signaling to Eliminate Aβ Deposition

Hyperlipidemia has been demonstrated to evoke Alzheimer disease (AD) pathologies such as Amyloid-β (Aβ) deposition and synaptogenesis dysfunction in the hippocampus. Curcumin gives protection against anti-amyloid properties and synaptogenesis dysfunction. Curcumin-Nicotinate (CurTn), a new type of curcumin derivative, ameliorates cognitive impairment by rescuing autophagic flux in the CA1 hippocampus of diabetic rats. However, whether Curtn possesses an antagonistic effect on AD-related pathologies in the hippocampus induced by hyperlipidemia remains ill-defined. The present study aims to investigate whether CurTn alleviates synaptogenesis dysfunction by promoting the activation of brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB)/cAMP-response element binding protein (CREB) signaling and whether the underlying fundamental mechanism involves the elimination of Aβ deposition due to Idol/low-density lipoprotein receptor (LDLR) signaling in the hippocampus of high-fat diet (HFD)-induced hyperlipidemia rats. The results demonstrated that CurTn not only improved synaptogenesis dysfunction in the hippocampus of HFD rats, as evidenced by the increases in the expressions of synapse-related proteins postsynaptic density protein 95 (PSD-95), synapsin-1, and Glutamate receptor 1 (GluR1), but also activated BDNF/TrkB/CREB signaling, as evidenced by the elevation of the expressions of BDNF, pTrkB, and CREB. Moreover, CurTn modulated the Idol/LDLR pathway in the hippocampus of HFD rats, as evidenced by the decreased expression of Idol and the increased expression of LDLR. Furthermore, CurTn eliminated the deposition of Aβ, as evidenced by the reduction in the content of Aβ40 and Aβ42. These results reveal that CurTn may attenuate synaptogenesis dysfunction by activating BDNF/TrkB/CREB signaling, as the possible result of the modulation of Idol/LDLR signaling to eliminate Aβ deposition in the hippocampus of HFD rats.

A biomimetic double network hydrogel ameliorates renal fibrosis and promotes renal regeneration

Acute kidney injury (AKI) and chronic kidney disease (CKD) are serious global public health issues. Both interconnect closely, and AKI-CKD transition significantly increases the morbidity of CKD and inevitably progresses to end stage renal disease. However, with the current drug delivery system it is hard to achieve precise delivery and apply it to clinical practice due to the local fibrotic milieu of the AKI-CKD transition procedure. Consequently, new treatment options to halt or even reverse AKI-CKD transition are urgently needed. Curcumin and Ac-SDKP were proved to be capable of ameliorating renal injury and restoring renal biological function. However, due to the water-insolubility, poor absorption and ease of degradation features, their utilization based on traditional drug delivery systems was still confined to the laboratory. A new approach for the targeted delivery of curcumin and Ac-SDKP into kidneys is needed. Hydrogels, owing to their capability of targeted-drug delivery and bio-favorable nature, emerge as a promising resolution. Herein, we developed a bioinspired double network hydrogel scaffold loaded with curcumin and N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) to explore the feasibility of drug-loaded hydrogels for treatment of AKI-CKD transition. This double network hydrogel (GCS) was prepared based on gelatin and curcumin-zinc with polydopamine (DOPA) coating and then immobilized with Ac-SDKP on the surface. The prepared hydrogels possessed appropriate porosity, suitable mechanical properties, and excellent biocompatibility. In vitro, the GCS hydrogel was demonstrated to be pro-angiogenic, anti-oxidative and anti-fibrotic. In vivo, after the GCS hydrogel was implanted into partially nephrectomized rat kidneys, local renal fibrosis was observed to be improved significantly, and neo-blood vessels and neonatal renal tubules appeared around the implanted area. We speculated that the GCS hydrogel could ameliorate renal fibrosis and injury significantly and stimulate regeneration in situ. Taken together, this study demonstrated the promising potential of this bioinspired hydrogel scaffold for renal injury repair and renal regeneration.

Asian Pigeonwing Plants (Clitoria ternatea) Synergized Mesenchymal Stem Cells by Modulating the Inflammatory Response in Rats with Cisplatin-Induced Acute Kidney Injury

Acute kidney injury is a heterogeneous set of disorders distinguished by a sudden decrease in the glomerular filtration rate, which is evidenced by an increase in the serum creatinine concentration or oliguria and categorized by stage and cause. It is an ever-growing health problem worldwide, with no reliable treatment. In the present study, we evaluated the role of Clitoria ternatea combined with mesenchymal stem cells in treating cisplatin-induced acute kidney injury in rats. Animals were challenged with cisplatin, followed by 400 mg/kg of Asian pigeonwing extract and/or mesenchymal stem cells (106 cells/150 g body weight). Kidney functions and enzymes were recorded, and histopathological sectioning was also performed. The expression profile of IL-1β, IL-6, and caspase-3 was assessed using the quantitative polymerase chain reaction. The obtained data indicated that mesenchymal stem cells combined with the botanical extract modulated the creatinine uric acid and urea levels. Cisplatin increased the level of malondialdehyde and decreased the levels of both superoxide dismutase and glutathione; however, the dual treatment was capable of restoring the normal levels. Furthermore, all treatments modulated the IL-6, IL-1β, and caspase-3 gene expression profiles. The obtained data shed some light on adjuvant therapy using C. ternatea and mesenchymal stem cells in treating acute kidney injury; however, further investigations are required to understand these agents’ synergistic mechanisms fully. The total RNA was extracted from the control, the positive control, and all of the therapeutically treated animals. The expression profiles of the IL-6, IL-1β, and caspase-3 genes were evaluated using the real-time polymerase chain reaction. Cisplatin treatment caused a significant upregulation in IL-6. All treatments could mitigate the IL-6-upregulating effect of cisplatin, with the mesenchymal stem cell treatment being the most effective. The same profile was observed in the IL-1β and caspase-3 genes, except that the dual treatment (mesenchymal stem cells and the botanical extract) was the most effective in ameliorating the adverse effect of cisplatin; it downregulated caspase-3 expression better than the positive control.

Aflatoxin B1 Toxicity and Protective Effects of Curcumin: Molecular Mechanisms and Clinical Implications

One of the most significant classes of mycotoxins, aflatoxins (AFTs), can cause a variety of detrimental outcomes, including cancer, hepatitis, aberrant mutations, and reproductive issues. Among the 21 identified AFTs, aflatoxin B1 (AFB1) is the most harmful to humans and animals. The mechanisms of AFB1-induced toxicity are connected to the generation of excess reactive oxygen species (ROS), upregulation of CYP450 activities, oxidative stress, lipid peroxidation, apoptosis, mitochondrial dysfunction, autophagy, necrosis, and inflammatory response. Several signaling pathways, including p53, PI3K/Akt/mTOR, Nrf2/ARE, NF-κB, NLRP3, MAPKs, and Wnt/β-catenin have been shown to contribute to AFB1-mediated toxic effects in mammalian cells. Curcumin, a natural product with multiple therapeutic activities (e.g., anti-inflammatory, antioxidant, anticancer, and immunoregulation activities), could revise AFB1-induced harmful effects by targeting these pathways. Therefore, the potential therapeutic use of curcumin against AFB1-related side effects and the underlying molecular mechanisms are summarized. This review, in our opinion, advances significant knowledge, sparks larger discussions, and drives additional improvements in the hazardous examination of AFTs and detoxifying the application of curcumin.

Hederagenin ameliorates cisplatin-induced acute kidney injury via inhibiting long non-coding RNA A330074k22Rik/Axin2/β-catenin signalling pathway

BACKGROUND

Acute kidney injury (AKI), a kidney disease with high morbidity and mortality, is characterized by a dramatic decline in renal function. Hederagenin (HDG), a pentacyclic triterpenoid saponin isolated from astragalus membranaceus, has been shown to have significant anti-inflammatory effects on various diseases. However, the effects of HDG on renal injury and inflammation in AKI has not been elucidated.

METHODS

In this research, mice model of AKI was established by intraperitoneal injection of cisplatin in vivo, the inflammatory model of renal tubular epithelial cells was established by LPS stimulation in vitro, and HDG was used to intervene in vitro and in vivo models. Transcriptome sequencing was used to analyze the alterations of LncRNA and mRNA expression in AKI model and LncRNA-A330074k22Rik (A33) knockdown cells, respectively. Renal in situ electrotransfer knockdown plasmid was used to establish mice model of AKI with low expression of A33 in kidney.

RESULTS

The results showed that HDG effectively alleviate cisplatin-induced kidney injury and inflammation in mice. Transcriptome sequencing results showed that multiple LncRNAs in kidney of AKI model exhibited significant changes, among which LncRNA-A33 had the most obvious change trend. Subsequent results showed that A33 was highly expressed in kidney of AKI mice and LPS-induced renal tubular cells. After in situ renal electroporation knockdown plasmid down-regulated A33 in kidney of AKI mice, it was found that inhibition of A33 could significantly relieve cisplatin-induced kidney injury and inflammation of AKI, while HDG could effectively suppress the expression of A33 in vitro and in vivo, respectively. Subsequently, transcriptome sequencing was again used to analyze the changes in mRNA expression of renal tubular cells after A33 knockdown by siRNA. The results showed that a large number of inflammation-related signaling pathways were down-regulated, Axin2 and its downstream β-catenin signal were significantly inhibited. Cell recovery test showed that HDG inhibited Axin2/β-catenin signal by down-regulating A33, and improved kidney injury and inflammation of AKI.

CONCLUSION

Taken together, HDG significantly ameliorated cisplatin-induced kidney injury through LncRNA-A330074k22Rik/Axin2/β-catenin signal axis, which providing a potential therapeutic approach for the treatment of AKI.

Review of potential medical treatments for middle ear cholesteatoma

Middle ear cholesteatoma (MEC), is a destructive, and locally invasive lesion in the middle ear driven by inflammation with an annual incidence of 10 per 100,000. Surgical extraction/excision remains the only treatment strategy available and recurrence is high (up to 40%), therefore developing the first pharmaceutical treatments for MEC is desperately required. This review was targeted at connecting the dysregulated inflammatory network of MEC to pathogenesis and identification of pharmaceutical targets. We summarized the numerous basic research endeavors undertaken over the last 30+ years to identify the key targets in the dysregulated inflammatory pathways and judged the level of evidence for a given target if it was generated by in vitro, in vivo or clinical experiments. MEC pathogenesis was found to be connected to cytokines characteristic for Th1, Th17 and M1 cells. In addition, we found that the inflammation created damage associated molecular patterns (DAMPs), which further promoted inflammation. Similar positive feedback loops have already been described for other Th1/Th17 driven inflammatory diseases (arthritis, Crohn’s disease or multiple sclerosis). A wide-ranging search for molecular targeted therapies (MTT) led to the discovery of over a hundred clinically approved drugs already applied in precision medicine. Based on exclusion criteria designed to enable fast translation as well as efficacy, we condensed the numerous MTTs down to 13 top drugs. The review should serve as groundwork for the primary goal, which is to provide potential pharmaceutical therapies to MEC patients for the first time in history.

Role of curcumin in the treatment of acute kidney injury: research challenges and opportunities

BACKGROUND

Acute kidney injury (AKI) is a common complication in clinical inpatients, and it continues a high morbidity and mortality rate despite many clinical treatment measures. AKI is triggered by infections, surgery, heavy metal exposure and drug side effects, but current chemical drugs often fall short of expectations for AKI treatment and have toxic side effects. Therefore, finding new interventions and treatments, especially of natural origin, is of remarkable clinical significance and application. The herbal monomer curcumin is a natural phenolic compound extracted from the plant Curcuma longa and showed various biological activities, including AKI. Furthermore, recent studies have shown that curcumin restores renal function by modulating the immune system and the release of inflammatory mediators, scavenging oxygen free radicals, reducing apoptosis and improving mitochondrial dynamics. However, curcumin has a low bioavailability, which limits its clinical application. For this reason, it is essential to investigate the therapeutic effects and molecular mechanisms of curcumin in AKI, as well as to improve its bioavailability for curcumin formulation development and clinical application.

PURPOSE

This review summarizes the sources, pharmacokinetics, and limitations in the clinical application of curcumin and explores methods to optimize its bioavailability using nanotechnology. In particular, the therapeutic effects and molecular mechanisms of curcumin on AKI are highlighted to provide a theoretical basis for AKI treatment in clinical practices.

METHODS

This review was specifically searched by means of a search of three databases (Web of Science, PubMed and Science Direct), till December 2021. Search terms were "Curcumin", "Acute kidney injury", "AKI", " Pharmacokinetics", "Mitochondria" and "Nano formulations". The retrieved data followed PRISMA criteria (preferred reporting items for systematic review) RESULTS: Studies have shown that curcumin responded to AKI-induced renal injury and restored renal tubular epithelial cell function by affecting multiple signaling pathways in AKI models induced by factors such as cisplatin, lipopolysaccharide, ischemia/reperfusion, gentamicin and potassium dichromate. Curcumin was able to affect NF-κB signaling pathway and reduce the expression of IL-1β, IL-6, IL-8 and TNF-α, thus preventing renal inflammatory injury. In the prevention of renal tubular oxidative damage, curcumin reduced ROS production by activating the activity of Nrf2, HO-1 and PGC-1α. In addition, curcumin restored mitochondrial homeostasis by upregulating OPA1 and downregulating DRP1 expression, while reducing apoptosis by inhibiting the caspase-3 apoptotic pathway. In addition, due to the low bioavailability and poor absorption of curcumin in vivo, curcumin nanoformulations including nanoparticles, liposomes, and polymeric micelles are formulated to improve the bioavailability.

CONCLUSION

This review provides new ideas for the use of curcumin in the prevention and treatment of AKI by modulating the molecular targets of several different cellular signaling pathways.

Curcumin alleviates aristolochic acid nephropathy based on SIRT1/Nrf2/HO-1 signaling pathway

Aristolochic acid I (AA-I), presenting in a variety of natural medicinal plants, which could cause tubular epithelial cell injury. Curcumin (CUR), a polyphenolic substance isolated from turmeric, is a natural antioxidant. The aim of this experiment was to investigate whether CUR attenuated AA-I-induced renal injury in rats through the SIRT1/Nrf2/HO-1 signaling pathway. SD rats were treated with AA-I (10 mg/kg) or/and CUR (200 mg/kg) for 28 days to assess the protective effect of CUR on AA-I-induced renal injury in vivo. NRK-52E cells were treated with AA-I (40 μ M) or/and CUR (20 μ M) for 24 h in vitro. The intervention pathway of CUR against oxidative stress injury induced by AA-I was assessed by observing pathological changes, oxidative stress status, apoptosis and the expression of SIRT1/Nrf2/HO-1 signaling pathway-related factors. The results showed that AA-I exposure increased the contents of BUN, Cr, KIM-1, NGAL, ALT and AST in serum. It increased the content of MDA, decreased the activities of SOD, GST, GSH and the content of ATP in renal tissue. Pathological changes such as inflammatory cell infiltration and mitochondrial injury occurred in renal tissue. AA-I exposure resulted in a substantial rise in the levels of BAX, Ccaspase-9, Cleaved Caspase-9, Caspase-3, Cleaved Caspase-3 and a significant decrease in mRNA and protein expression levels of Bcl-2, SIRT1, Nrf2, NQO1, HO-1 and Keap1. However, these changes were reversed by CUR intervention. In summary, AA-I exposure caused mitochondrial dysfunction and triggered apoptosis through the oxidative stress pathway. However, CUR could reduce AA-I-induced renal injury by activating the SIRT1/Nrf2/HO-1 signaling pathway.

(9S,13R)-12-oxo-phytodienoic acid attenuates inflammation by inhibiting mPGES-1 and modulating macrophage polarization via NF-κB and Nrf2/HO-1 pathways

Non-steroidal anti-inflammatory drugs (NSAIDs) relieve inflammation by suppressing prostaglandin E₂/cyclooxygenase 2 (PGE₂/COX-2) with cardiovascular and gastrointestinal bleeding risk. Theoretically, suppressing PGE₂ through inhibiting the terminal synthase microsomal prostaglandin E₂ synthase-1 (mPGES-1) instead of upstream COX-2 is ideal for inflammation. Here, (9S,13R)-12-oxo-phytodienoic acid (AA-24) extracted from Artemisia anomala was first screened as an anti-inflammatory candidate and decreased inducible nitric oxide synthase (iNOS), nitric oxide (NO), mPGES-1, and PGE₂ without affecting COX-1/2, thromboxane A₂ (TXA₂) and prostaglandin I₂ (PGI₂). Besides, AA-24 suppressed the differentiation of M0 macrophages to M1 phenotype but enhanced it to M2 phenotype, blocked the activation of NF-κB pathway, and increased the activation of Nrf2 and heme oxygenase-1 (HO-1). Moreover, AA-24 selectively inhibited mPGES-1 and reduced inflamed paw edema in carrageenan-induced mice. In conclusion, AA-24 attenuates inflammation by inhibiting mPGES-1 and modulating macrophage polarization via the NF-κB and Nrf2/HO-1 pathways and could be a promising candidate for developing anti-inflammatory drugs.

Study of the Osteoimmunomodulatory Properties of Curcumin-Modified Copper-Bearing Titanium

Peri-implantitis can lead to implant failure. In this study, curcumin (CUR) was modified onto the copper-bearing titanium alloy (Cu-Ti) with the assistance of polydopamine (PDA) in order to study the bone immune response and subsequent osteogenesis. FE-SEM, XPS and water contact angle were utilized to characterize the coating surface. Bone marrow mesenchymal stem cells (BMSCs) and macrophages were cultured separately and together onto the CUR modified Cu-Ti. Cell activity, expression of relative genes and proteins, cell migration ability, and fluorescence staining of cells were performed. CUR modification slightly increased the activation of M1-type and M2-type cells under physiological conditions. In the inflammation state, CUR inhibited the overexpression of M1 macrophages and induced M2-type differentiation. In addition, the modification itself could provoke the expression of osteoblastic-related genes of BMSCs, while promoting the osteogenic differentiation of BMSCs through the activation of macrophages in both physiological and inflammatory states. The BMSCs migration was increased, the expression of osteogenic-related genes and proteins was up-regulated, and alkaline phosphatase activity (ALP) was increased. Thus, the modification of CUR can promote the osteointegration effect of Cu-Ti by bone immunomodulation and may, in addition, improve the success rate of implants.

Nephrotoxicity in cancer treatment: An update

It has been estimated that nearly 80% of anticancer drug-treated patients receive potentially nephrotoxic drugs, while the kidneys play a central role in the excretion of anticancer drugs. Nephrotoxicity has long been a serious complication that hampers the effectiveness of cancer treatment and continues to influence both mortality and length of hospitalization among cancer patients exposed to either conventional cytotoxic agents or targeted therapies. Kidney injury arising from anticancer drugs tends to be associated with preexisting comorbidities, advanced cancer stage, and the use of concomitant non-chemotherapeutic nephrotoxic drugs. Despite the prevalence and impact of kidney injury on therapeutic outcomes, the field is sorely lacking in an understanding of the mechanisms driving cancer drug-induced renal pathophysiology, resulting in quite limited and largely ineffective management of anticancer drug-induced nephrotoxicity. Consequently, there is a clear imperative for understanding the basis for nephrotoxic manifestations of anticancer agents for the successful management of kidney injury by these drugs. This article provides an overview of current preclinical research on the nephrotoxicity of cancer treatments and highlights prospective approaches to mitigate cancer therapy-related renal toxicity.

Drug Candidates for Autoimmune Diseases

Most of the immunosuppressive drugs used in the clinic to prevent organ rejection or to treat autoimmune disorders were originally isolated from fungi or bacteria. Therefore, in addition to plants, these are valuable sources for identification of new potent drugs. Many side effects of established drugs limit their usage and make the identification of new immunosuppressants necessary. In this review, we present a comprehensive overview of natural products with potent anti-inflammatory activities that have been tested successfully in different models of chronic inflammatory autoimmune diseases. Some of these candidates already have passed first clinical trials. The anti-inflammatory potency of these natural products was often comparable to those of established drugs, and they could be used at least in addition to standard therapy to reduce their dose to minimize unwanted side effects. A frequent mode of action is the inhibition of classical inflammatory signaling pathways, such as NF-κB, in combination with downregulation of oxidative stress. A drawback for the therapeutic use of those natural products is their moderate bioavailability, which can be optimized by chemical modifications and, in addition, further safety studies are necessary. Altogether, very interesting candidate compounds exist which have the potential to serve as starting points for the development of new immunosuppressive drugs.

Isoliquiritin Ameliorates Cisplatin-Induced Renal Proximal Tubular Cell Injury by Antagonizing Apoptosis, Oxidative Stress and Inflammation

Acute kidney injury (AKI) is a clinical syndrome characterized by morbidity, mortality, and cost. Cis-diamminedichloroplatinum (cisplatin) is a chemotherapeutic agent used to treat solid tumors and hematological malignancies, but its side effects, especially nephrotoxicity, limit its clinical application. Isoliquiritin (ISL), one of the major flavonoid glycoside compounds in licorice, has been reported to have anti-apoptotic, antioxidant, and anti-inflammatory activities. However, the effect and mechanism of ISL on cisplatin-induced renal proximal tubular cell injury remain unknown. In this study, mouse proximal tubular cells (mPTCs) and human proximal tubule epithelial cells (HK2) were administered increasing concentrations of ISL from 7.8125 to 250 μM. Moreover, mPTC and HK2 cells were pretreated with ISL for 6–8 h, followed by stimulation with cisplatin for 24 h. CCK-8 assay was performed to evaluate the cell viability. Apoptosis and reactive oxygen species (ROS) of cells were measured by using flow cytometer and western blotting. Our results showed that ISL had no obvious effect on cell viability. ISL decreased cisplatin-induced cell injury in a dose-dependent manner. ISL also protected against cisplatin-induced cell apoptosis. Meanwhile, the enhanced protein levels of Bax, cleaved caspase-3/caspase-3 ratio, levels of Pp-65/p-65, levels of IL-6, and the production of ROS induced by cisplatin were significantly attenuated by ISL treatment. Moreover, ISL markedly increased the protein levels of Bcl-2 and SOD2, which were reduced by cisplatin stimulation. These results showed that ISL ameliorated cisplatin-induced renal proximal tubular cell injury by antagonizing apoptosis, oxidative stress and inflammation.

Driving role of macrophages in transition from acute kidney injury to chronic kidney disease

Acute kidney injury (AKI), characterized by acute renal dysfunction, is an increasingly common clinical problem and an important risk factor in the subsequent development of chronic kidney disease (CKD). Regardless of the initial insults, the progression of CKD after AKI involves multiple types of cells, including renal resident cells and immune cells such as macrophages. Recently, the involvements of macrophages in AKI-to-CKD transition have garnered significant attention. Furthermore, substantial progress has also been made in elucidating the pathophysiological functions of macrophages from the acute kidney to repair or fibrosis. In this review, we highlight current knowledge regarding the roles and mechanisms of macrophage activation and phenotypic polarization, and transdifferentiation in the development of AKI-to-CKD transition. In addition, the potential of macrophage-based therapy for preventing AKI-to-CKD transition is also discussed.

Curcumin-Injected Musca domestica Larval Hemolymph: Cecropin Upregulation and Potential Anticancer Effect

Over recent decades, much attention has been given to imply the natural products in cancer therapy alone or in combination with other established procedures. Insects have a rich history in traditional medicine across the globe, which holds promise for the future of natural product drug discovery. Cecropins, peptides produced by insects, are components of a defense system against infections and are well known to exert antimicrobial and antitumor capabilities. The present study aimed to investigate, for the first time, the role of curcumin in enhancing the anticancer effect of Musca domestica larval hemolymph. Third larval instars of M. domestica were injected with curcumin and the hemolymph was picked at 4, 8, and 24 h post-curcumin injection. M. domestica cecropin A (MdCecA) was evaluated in control and injected larval hemolymphs. The cytotoxicity on breast cancer cell lines (MCF-7) and normal Vero cells was assessed to be comparable to control larval hemolymph. Curcumin-injected larval hemolymphs exhibited significant cytotoxicity with respect to the uninjected ones against MCF-7; however, Vero cells showed no cytotoxicity. The IC50 was 106 ± 2.9 and 388 ± 9.2 μg/mL for the hemolymphs of injected larvae at 4 and 8 h, respectively, while the control larval hemolymph revealed the IC50 of >500 μg/mL. For mechanistic anticancer evaluation, concentrations of 30, 60, and 100 μg/mL of curcumin-injected larval hemolymphs were examined. A significant G2/M cell cycle arrest was observed, confirming the anti-proliferative properties of hemolymphs over the tested concentrations. The MdCecA transcripts were significantly (p < 0.05) upregulated at 4 and 8 h post-injection, while a significant downregulation was observed after 24 h. Cecropin quantification by LC−MS revealed that MdCecA peptides have the highest expression in the hemolymph of the treated larvae at 8 h relative to the control group. The upregulation of cecropin expression at mRNA and protein levels may be attributed to the curcumin stimulation and linked to the increased cytotoxicity toward the cancer cell line. In conclusion, the results suggest that the apoptotic and anti-proliferative effects of M. domestica hemolymph on MCF-7 cells following the curcumin injection can be used as a natural candidate in future pharmaceutical industries.

Water extract of Cayratia albifolia C.L.Li root relieves zymosan A-induced inflammation by restraining M1 macrophage polarization

BACKGROUND

Cayratia albifolia C.L.Li (CAC) is a traditional Chinese herbal medicine used to treat inflammatory diseases. Our laboratory has firstly reported that the water extract from CAC relieved lipopolysaccharide (LPS)-induced inflammation, however stronger evidence is still needed to prove its anti-inflammatory effects and the mechanisms involved are also ambiguous.

PURPOSE

This study sought to provide more evidence for the application of CAC in alleviating infectious inflammation and disclose novel pharmacological mechanisms.

METHODS

Mice were injected with zymA into their paws or peritoneal cavities, and then treated with CAC. ELISA, immunofluorescence and flow cytometry were performed to detect the cytokines (IL-1β, IL-6, TNF-α and IL-10) generation, the cell infiltration, and the CD86 or CD206 expression of macrophages. Then in vitro assays were performed on bone marrow-derived macrophages (BMDMs) and peritoneal macrophages (PMs) to detect their expression of iNOS, arg-1 and the cytokines above. On mechanisms, western blotting (WB), electrophoretic mobility shift assay (EMSA) and flow cytometry were carried out to measure NF-κB transcriptional activity, mitochondrial bioactivity and the mTORC1 activation when BMDMs were stimulated by zymA and treated with CAC. Finally, the chemical components consisted in the extract were analyzed by LC-MS.

RESULTS

200 mg/kg CAC clearly inhibited zymA induced mouse paw edema and reduced the contents of IL-1β, IL-6 and TNF-α rather than IL-10 in local tissues. CAC also reduced CD86 but not CD206 in macrophages in situ. Through in vitro experiments, it was discovered that CAC reduced the protein and mRNA levels of IL-1β, IL-6 and TNF-α, and also inhibited iNOS expression, but showed no influence on IL-10 and arg-1 in macrophages. We found CAC reduced NF-κB transcriptional activity, down-regulated mitochondrial membrane potential and ROS levels, and inhibited mTORC1 activity. Finally, we identified 15 major compounds in the extract, among which 4-guanidinobutyric acid and kynurenic acid were the most abundant.

CONCLUSION

This study provides further evidence that CAC significantly reduces zymA induced infectious inflammation. In addition, this novel data revealed that CAC restrained M1 rather than promoting M2 macrophages polarization via multi-target inhibitory effects, based on its potentially active components.

Astragalus mongholicus Bunge and Panax notoginseng formula (A&P) improves renal mesangial cell damage in diabetic nephropathy by inhibiting the inflammatory response of infiltrated macrophages

BACKGROUND

Diabetic nephropathy (DN) is one of the main causes of end-stage renal disease with scantly effective treatment. Numerous evidences indicated that macrophages play an important role in the occurrence and pathogenesis of DN by secreting inflammatory cytokines. Mincle is mainly expressed in macrophages and promotes kidney inflammation and damage of acute kidney injury. However, the role of Mincle in DN is unclear. In this study, we aim to investigate the effect of Mincle-related macrophage inflammation on DN, and whether it can be identified as the therapeutic target for Astragalus mongholicus Bunge and Panax notoginseng Formula (A&P), a widely used Chinese herbal decoction for DN treatment.

METHODS

In vivo experiments high-fat and high-sugar diet and streptozotocin was used to establish a diabetic nephropathy model, while in vitro experiments inflammation model was induced by high-glucose in mouse Bone Marrow-Derived Macrophages (BMDM) cells and mouse mesangial (MES) cells. Kidney pathological staining is used to detect kidney tissue damage and inflammation, Western blotting, Real-time PCR and ELISA are performed to detect Mincle signaling pathway related proteins and inflammatory cytokines.

RESULTS

Mincle was mainly expressed in infiltrated macrophage of DN kidney, and was significant decreased after A&P administration. The in vitro experiments also proved that A&P effectively down-regulated the expression of Mincle in macrophage stimulated by high glucose. Meanwhile, the data demonstrated that A&P can reduce the activation of NFκB, and the expression and secretion of inflammatory cytokines in DN kidney or BMDM cells. Notably, we set up a co-culture system to conform that BMDM cells can aggravate the inflammatory response of mesangial (MES) cells under high glucose stimulation. Furthermore, we found that the anti-injury role of A&P in MES cells was dependent on inhibition of the Mincle in macrophage.

CONCLUSION

In summary, our study found that A&P is effective in reducing renal pathological damage and improving renal function and inflammation in diabetic nephropathy by a mechanism mainly related to the inhibition of the Mincle/Card9/NFκB signaling pathway.

A novel mechanism for NLRP3 inflammasome activation

The NLRP3 inflammasome, as an important component of the innate immune system, plays vital roles in various metabolic disorders. It has been reported that the NLRP3 inflammasome can be activated by a broad range of distinct stimuli, such as K⁺ efflux, mitochondrial dysfunction, lysosomal disruption and trans-Golgi disassembly, etc. However, there has been no well-established model for NLRP3 inflammasome activation so far, especially the underlying mechanisms for mitochondria in NLRP3 inflammasome activation remain elusive. Given that K⁺ efflux is a widely accepted nexus for triggering activation of NLRP3 inflammasome in most previous studies, we sought to elucidate the role of mitochondria in K⁺ efflux-induced NLRP3 inflammasome activation. Here, we demonstrated that inflammation activation by LPS evoked the expression of genes that involved in mitochondrial biogenesis and mitophagy, subsequently mitochondrial mass and mitochondrial membrane potential were also elevated, suggesting the contribution of mitochondria in inflammatory responses. Moreover, we inhibited mitochondrial biogenesis by silencing Tfam and genetic ablation of Tfam abolished the NLRP3 inflammasome activation induced by K⁺ efflux via release of mitochondrial DNA (mtDNA), as deprivation of cellular mtDNA by EtBr treatment could reverse inflammasome activation induced by K⁺ efflux. Collectively, we reveal that mtDNA release induced by K⁺ efflux in macrophages activates NLRP3 inflammasome, and propose that mitochondria may serve as a potential therapeutic target for NLRP3 inflammasome-related diseases.

Natural products: potential treatments for cisplatin-induced nephrotoxicity

Cisplatin is a clinically advanced and highly effective anticancer drug used in the treatment of a wide variety of malignancies, such as head and neck, lung, testis, ovary, breast cancer, etc. However, it has only a limited use in clinical practice due to its severe adverse effects, particularly nephrotoxicity; 20%–35% of patients develop acute kidney injury (AKI) after cisplatin administration. The nephrotoxic effect of cisplatin is cumulative and dose dependent and often necessitates dose reduction or withdrawal. Recurrent episodes of AKI result in impaired renal tubular function and acute renal failure, chronic kidney disease, uremia, and hypertensive nephropathy. The pathophysiology of cisplatin-induced AKI involves proximal tubular injury, apoptosis, oxidative stress, inflammation, and vascular injury in the kidneys. At present, there are no effective drugs or methods for cisplatin-induced kidney injury. Recent in vitro and in vivo studies show that numerous natural products (flavonoids, saponins, alkaloids, polysaccharide, phenylpropanoids, etc.) have specific antioxidant, anti-inflammatory, and anti-apoptotic properties that regulate the pathways associated with cisplatin-induced kidney damage. In this review we describe the molecular mechanisms of cisplatin-induced nephrotoxicity and summarize recent findings in the field of natural products that undermine these mechanisms to protect against cisplatin-induced kidney damage and provide potential strategies for AKI treatment.

Mechanistic insights into the renoprotective role of curcumin in cisplatin-induced acute kidney injury: network pharmacology analysis and experimental validation

Cisplatin-induced acute kidney injury (CP-AKI) is a severe complication in patients receiving CP chemotherapy. However, effective therapies for CP-AKI are currently lacking. Curcumin (CUR), a natural polyphenol, is extracted from the rhizome of turmeric and has been reported to have nephroprotective activity. However, the role of CUR in CP-AKI remains unclear. This study aimed to explore the mechanism of CUR in CP-AKI by combining a network pharmacology approach with experimental validations. The analysis revealed 176 potential targets of CUR based on the HERB database and 1,286 related targets of CP-AKI from the GeneCards, DrugBank, and OMIM databases. Further, 106 common targets of CUR against CP-AKI were obtained, and these common targets constructed a protein-protein interaction (PPI) network. In addition, the core targets were screened from the PPI network using Cytoscape. Molecular docking revealed that CUR displayed the best binding to AKT1. Gene Ontology (GO) analysis indicated that the primary biological processes of CUR against CP-AKI included cellular response to chemical stress and apoptotic regulation. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis suggested that the PI3K-Akt signaling pathway was most significantly enriched in CUR against CP-AKI. Western blotting and flow cytometry showed that CUR inhibited apoptosis induced by CP by activating the Akt signaling pathway in human kidney tubular epithelial cells (HK-2). Altogether, our findings demonstrated that CUR alleviated apoptosis by activating the Akt signaling pathway in CP-AKI in vitro. These data provide a scientific basis for future investigations into the clinical application of CUR against CP-AKI.

Recent advancement on development of drug-induced macrophage polarization in control of human diseases

Macrophages, an important part of human immune system, possess a high plasticity and heterogeneity (macrophage polarization) as classically activated macrophages (M1) and alternatively activated macrophages (M2), which exert pro-inflammatory/anti-tumor and anti-inflammatory/pro-tumor effects, respectively. Thus, drug development in induction of macrophage polarization could be used to treat different human diseases. This review summarizes the recent advancement on modulation of macrophage polarization and its related molecular mechanisms induced by a number of agents. Research on the anti-inflammatory drugs to regulate the macrophage polarization accounts for a large proportion in the field and types of diseases investigated could include atherosclerosis, enteritis, nephritis, and the nervous system and skeletal diseases, while study of the anti-tumor agents to modify macrophage polarization is a novel area of research. Future study of the molecular mechanisms by which the different agents regulate the macrophage polarization could lead to an effective control of various human diseases, including inflammation and cancers.

Curcumin and its derivatives in cancer therapy: Potentiating antitumor activity of cisplatin and reducing side effects

Curcumin is a phytochemical isolated from Curcuma longa with potent tumor-suppressor activity, which has shown significant efficacy in pre-clinical and clinical studies. Curcumin stimulates cell death, triggers cycle arrest, and suppresses oncogenic pathways, thereby suppressing cancer progression. Cisplatin (CP) stimulates DNA damage and apoptosis in cancer chemotherapy. However, CP has adverse effects on several organs of the body, and drug resistance is frequently observed. The purpose of the present review is to show the function of curcumin in decreasing CP's adverse impacts and improving its antitumor activity. Curcumin administration reduces ROS levels to prevent apoptosis in normal cells. Furthermore, curcumin can inhibit inflammation via down-regulation of NF-κB to maintain the normal function of organs. Curcumin and its nanoformulations can reduce the hepatoxicity, neurotoxicity, renal toxicity, ototoxicity, and cardiotoxicity caused by CP. Notably, curcumin potentiates CP cytotoxicity via mediating cell death and cycle arrest. Besides, curcumin suppresses the STAT3 and NF-ĸB as tumor-promoting pathways, to enhance CP sensitivity and prevent drug resistance. The targeted delivery of curcumin and CP to tumor cells can be mediated nanostructures. In addition, curcumin derivatives are also able to reduce CP-mediated side effects, and increase CP cytotoxicity against various cancer types.

LncRNA GAS5 protects against TGF-β-induced renal fibrosis via the Smad3/miRNA-142-5p axis

Increasing evidence shows that long noncoding RNAs (lncRNAs) play an important role in kidney disease. In this study, we investigated the role of the lncRNA growth arrest-specific 5 (GAS5) in the pathogenesis of renal fibrosis. We found that GAS5 was markedly decreased in the fibrotic kidney of a unilateral ureteral obstructive nephropathy mouse model. In addition, GAS5 was expressed in mouse tubular epithelial cells (mTECs) and interstitial fibroblasts in normal renal tissue and was especially highly expressed in the cytoplasm. In vitro experiments showed that GAS5 was downregulated by transforming growth factor-β1 (TGF-β1) in a dose- and time-dependent manner. Overexpression of GAS5 blocked TGF-β1-induced collagen type I and fibronectin expression and vice versa. Mechanistic experiments revealed that Smad3 but not Smad2 drove the regulation of GAS5. More importantly, GAS5 interacted with miR-142-5p and was involved in the renoprotective effect by participating in the competing endogenous RNA network. Finally, we also found that knockdown of GAS5 promoted TGF-β1-induced mouse tubular epithelial cell apoptosis via the Smad3 pathway. Taken together, our results uncovered a lncRNA/miRNA competing endogenous RNA network-based mechanism that modulates extracellular matrix formation and cell apoptosis via the Smad3 pathway.NEW & NOTEWORTHY In this work, we mainly discuss long noncoding RNA growth arrest-specific 5 (GAS5), acting in a renoprotective role via the Smad3/miRNA-142-5p axis, that modulates extracellular matrix formation and cell apoptosis. Overexpression of GAS5 effectively blocked renal fibrosis in vitro. This study reveals that GAS5 may represent as a novel and precision therapeutic target for alleviating renal fibrosis.

Indispensable role of mitochondria in maintaining the therapeutic potential of curcumin in acute kidney injury

Acute kidney injury (AKI) is a serious disease for which effective therapeutic agents are required. The capacity of curcumin (CUR) to resolve renal inflammation/oxidative stress and mitochondrial damage has been reported, but crosstalk between these effects and the consequence of this crosstalk remain elusive. In this study, a hypoxia/reoxygenation (H/R)-induced renal tubular epithelial cell (TEC) injury model and an ischaemia/reperfusion (I/R)-induced mouse AKI model were treated with CUR with or without mitochondrial inhibitors (rotenone and FCCP) or siRNA targeting mitochondrial transcription factor A (TFAM). Changes in mitochondrial function, inflammation, the antioxidant system and related pathways were analysed. In vitro, CUR suppressed NFκB activation and cytokine production and induced NRF2/HO-1 signalling in TECs under H/R conditions. CUR treatment also reduced mitochondrial ROS (mtROS) and mitochondrial fragmentation and enhanced mitochondrial biogenesis, TCA cycle activity and ATP synthesis in damaged TECs. However, the anti-inflammatory and antioxidant effects of CUR in damaged TECs were markedly abolished upon mitochondrial disruption. In vivo, CUR treatment improved renal function and antioxidant protein (NRF2 and SOD2) expression and reduced oxidative stress (8-OHdG), tubular apoptosis/death, cytokine release/macrophage infiltration and mitochondrial damage in the kidneys of AKI mice. In vitro, the anti-inflammatory and antioxidant effects of CUR in damaged kidneys were impaired when mitochondrial function was disrupted. These results suggest mitochondrial damage is a driving factor of renal inflammation and redox imbalance. The therapeutic capacity of CUR in kidneys with AKI is primarily dependent on mitochondrial mechanisms; thus, CUR is a potential therapy for various diseases characterized by mitochondrial damage.

hnRNPK knockdown alleviates NLRP3 inflammasome priming by repressing FLIP expression in Raw264.7 macrophages

Objectives: Inflammation is an important predisposing and progressive factor in chronic kidney disease (CKD). Heterogeneous nuclear ribonucleoprotein K (hnRNPK) is associated with many fundamental cellular processes, but in chronic inflammatory pathologies remains unclear.

Methods: An in vitro peripheral inflammation model was established using lipopolysaccharide (LPS)-stimulated mouse RAW264.7 macrophages, followed by inflammasome activation by ATP treatment. Knockdown of hnRNPK by sihnRNPK and FLICE-like inhibitory protein (FLIP) by siFLIP transfection were achieved in Raw264.7 macrophages. ELISA was used to determine the expression of IL-1β, IL-18 and TNF-α. Real time PCR was applied to detect the mRNA levels of hnRNPK, NOD-like receptors family pyrin domain-containing 3 (NLRP3), FLIP, Caspase-1, IL-1β and IL-18. Western blot and immunofluorescence were performed to detect relevant protein expressions. Co-immunoprecipitation (Co-IP) was used to assess the interaction of hnRNPK with FLIP.

Results: Results showed that LPS plus ATP activated NLRP3 inflammasome, which evidenced by the up-regulation of TNF-α, IL-1β and IL-18. Notably, hnRNPK and FLIP were significantly up-regulated in activated NLRP3 inflammasome of macrophages. HnRNPK or FLIP knockdown significantly suppressed the activation of NLRP3 inflammasome, as reflected by down-regulation of Caspase-1, IL-1β and IL-18. Importantly, hnRNPK could directly bind to FLIP in activated NLRP3 inflammasome.

Discussion: Our findings suggest that hnRNPK could promote the activation of NLRP3 inflammasome by directly binding FLIP, which might provide potential new therapeutic targets for CKD.

Forsythiae Fructus aqueous extract attenuates cisplatin-induced kaolin consumption (pica) by inhibiting NLRP3 inflammasome activation in rats

The present study was conducted to evaluate the effect of Forsythiae Fructus aqueous extract (FAE) against cisplatin-induced emesis and to explore the antiemetic mechanism of FAE by focusing on NLRP3 inflammasome activation in a rat pica model. Our results showed that FAE significantly ameliorated cisplatin-induced acute and delayed pica in rats. Moreover, FAE improved the gastrointestinal histopathological injury and reduced the levels of serum ROS, IL-1β, and IL-18 in cisplatin-treated rats. In addition, the expressions of NLRP3, ASC, caspase-1, and IL-1β and the colocalization of the NLRP3 with ASC or caspase-1 in rat gastric antrum and ileum were also suppressed by FAE. Taken together, our findings indicate that FAE has a therapeutic effect against CINV, which may be related to its inhibition of the activation of NLRP3 inflammasome.

Research progress of phenolic compounds regulating IL-6 to exert antitumor effects

Cytokine therapy, which activates the host immune system, has become an important and novel therapeutic approach to treat various cancers. Recent studies have shown that IL-6 is an important cytokine that regulates the homeostasis in vivo. However, excessive IL-6 plays a pathological role in a variety of acute and chronic inflammatory diseases, especially in cancer. IL-6 can transmit signals through JAK/STAT, RAS /MAPK, PI3K/ Akt, NF-κB, and other pathways to promote cancer progression. Phenolic compounds can effectively regulate the level of IL-6 in tumor cells and improve the tumor microenvironment. This article focuses on the phenolic compounds through the regulation of IL-6, participate in the prevention of cancer, inhibit the proliferation of cancer cells, reduce angiogenesis, improve therapeutic efficacy, and reduce side effects and other aspects. This will help to further advance research on cytokine therapy to reduce the burden of cancer and improve patient prognosis. However, current studies are mostly limited to animal and cellular experiments, and high-quality clinical studies are needed to further determine their antitumor efficacy in humans.