C5a Induces the Synthesis of IL-6 and TNF-α in Rat Glomerular Mesangial Cells through MAPK Signaling Pathways

Identification of key extracellular proteins as the potential biomarkers in thyroid eye disease

BACKGROUND

Thyroid eye disease (TED) is one of the most common autoimmune orbital diseases in adults. The early diagnosis and effective treatment of TED is a worldwide problem. Extracellular proteins may act as indicators in bodily fluids. Our research sought to identify the roles of extracellular proteins and possible biomarkers in TED using a bioinformatics study.

METHODS

Data from Gene Expression Omnibus (GEO) were acquired to create the TED expression profiles. The annotation database screened extracellular proteins with differentially expressed genes (EP-DEGs). To investigate both the function and the route of EP-DEGs, GO and KEGG were utilized. Hub genes and protein-protein interaction (PPI) networks among EP-DEGs were discovered. Key EP-DEGs' diagnostic potency was assessed using the receiver operating characteristic (ROC) curve.

RESULTS

102 EP-DEGs underwent screening. The extracellular matrix, which contains collagen, the receptor-ligand activity, the interaction between cytokines and their receptors, and the complement and coagulation cascades route, were all enhanced in EP-DEGs. The EP-DEG PPI network contained 233 edges and 78 nodes. We discovered 21 extracellular proteins that interacted with EGFR in addition to 3 major extracellular proteins, EGFR, CD44, and CXCL8, all of which had significant values of AUC (> 0.7).

CONCLUSIONS

In conclusion, EGFR, CD44, and CXCL8 may be the potential biomarker in the TED. this research gives us a theoretical foundation for understanding how TED pathogenesis occurs.

A comprehensive assessment of smokeless tobacco (Shammah) extract: unraveling the effects on hematological parameters, antioxidant defense mechanisms, and organ health in rats

Shammah, also known as smokeless tobacco, is a form of tobacco product consumed without combustion, commonly used in various cultures, particularly in the Middle East and parts of Africa. The experiment was conducted in four groups control male and female, also treated male and female. The administration of Shammah extract induced significant hematological, biochemical, and histopathological changes in both female and male rats. Treated females showed a decrease in total leukocyte count (TLC) to 9900, while treated males increased to 14,525. Lymphocyte percentage decreased by 9.5% in females and 6.02% in males, with neutrophil counts rising by 24.6% and 20.5%, respectively. Eosinophil levels surged by 240% in females and 50.3% in males. Hemoglobin levels decreased by 12.4-13.1% in females, while males showed a non-significant increase to 15.68. Malondialdehyde (MDA) levels increased to 1.57 in females (57% increase) and 1.93 in males (70.8% increase). Antioxidant enzymes decreased, with superoxide dismutase (SOD) at 3.53 (116.2% decrease) in females and 3.90 (45.8% decrease) in males. Kidney function assessments revealed elevated urea levels of 36.35 (84.8% increase) in females and 43.17 (131.2% increase) in males, alongside creatinine levels of 1.28 (75.3% increase) in females and 1.56 (90.2% increase) in males. Histopathological examinations showed untreated livers with a typical structure, while treated livers exhibited infiltrative cell aggregations, venous congestion, hemorrhage, and edema. Treated kidneys showed severe glomerular atrophy and degeneration. Spleens from treated groups had blending of white and red pulp, while brains displayed hemorrhage and distorted neurons in males, and ghost neurons in females. Treated testes exhibited dilated blood vessels, edema, and reduced spermatogenesis, while treated ovaries showed cyst formation and vacuolar degeneration. These findings indicate significant oxidative stress and organ damage associated with Shammah extract exposure.

Action of the Terminal Complement Pathway on Cell Membranes

The complement pathway is one of the most ancient elements of the host's innate response and includes a set of protein effectors that rapidly react against pathogens. The late stages of the complement reaction are broadly categorised into two major outcomes. Firstly, C5a receptors, expressed on membranes of host cells, are activated by C5a to generate pro-inflammatory responses. Secondly, target cells are lysed by a hetero-oligomeric pore known as the membrane attack complex (MAC) that punctures the cellular membrane, causing ion and osmotic flux. Generally, several membrane-bound and soluble inhibitors protect the host membrane from complement damage. This includes inhibitors against the MAC, such as clusterin and CD59. This review addresses the most recent molecular and structural insights behind the activation and modulation of the integral membrane proteins, the C5a receptors (C5aR1 and C5aR2), as well as the regulation of MAC assembly. The second aspect of the review focuses on the molecular basis behind inflammatory diseases that are reflective of failure to regulate the terminal complement effectors. Although each arm is unique in its function, both pathways may share similar outcomes in these diseases. As such, the review outlines potential synergy and crosstalk between C5a receptor activation and MAC-mediated cellular responses.

The Effect and Mechanism of Fufang Banbianlian Injection in the Treatment of Mesangial Proliferative Glomerulonephritis

OBJECTIVE

Mesangial proliferative glomerulonephritis (MsPGN) is an important cause of chronic kidney disease. Abnormal proliferation of mesangial cells and immune-inflammatory response are its important pathological manifestations. Currently, there is no ideal treatment for this disease. Fufang Banbianlian Injection (FBI) has anti-inflammatory, antioxidant, and immuneenhancing effects, and is mostly used for the treatment of bronchitis, pneumonia, and respiratory tract infections in children.

METHODS

A rat model of MsPGN was established and treated with FBI. The efficacy was tested through pathological experiments and urine protein quantification. Network pharmacology methods were used to predict the signaling pathways and key proteins that exert the efficacy of FBI, and were screened through molecular docking experiments. The active substances that work were verified through cell experiments.

RESULTS

The results confirmed that intervention with FBI can inhibit the proliferation of glomerular cells and reduce the infiltration of macrophages, thereby reducing the pathological damage of rats with mesangial proliferative nephritis; it has been found to have an obvious therapeutic effect. Molecular docking results have shown kaempferol (Kae), the main component of FBI, to have a good affinity for key targets. The results of in vitro verification experiments showed that FBI and its active ingredient Kae may play a therapeutic role by regulating the NF-κB signaling pathway in mesangial cells, inhibiting its activation and the secretion of proinflammatory cytokines.

CONCLUSION

Through network pharmacology, molecular docking, and experimental verification, it was confirmed that FBI and its active ingredient Kae can reduce the molecular mechanism of pathological damage of MsPGN by regulating the NF-κB signaling pathway and providing potential therapeutic drugs for the treatment of this disease.

Chinese herbal medicine for the treatment of diabetic nephropathy: From clinical evidence to potential mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic nephropathy (DN) is a typical chronic microvascular complication of diabetes, characterized by proteinuria and a gradual decline in renal function. At present, there are limited clinical interventions aimed at preventing the progression of DN to end-stage renal disease (ESRD). However, Chinese herbal medicine presents a distinct therapeutic approach that can be effectively combined with conventional Western medicine treatments to safeguard renal function. This combination holds considerable practical implications for the treatment of DN.

AIM OF THE STUDY

This review covers commonly used Chinese herbal remedies and decoctions applicable to various types of DN, and we summarize the role played by their active ingredients in the treatment of DN and their mechanisms, which includes how they might improve inflammation and metabolic abnormalities to provide new ideas to cope with the development of DN.

MATERIALS AND METHODS

With the keywords "diabetic nephropathy," "Chinese herbal medicine," "clinical effectiveness," and "bioactive components," we conducted an extensive literature search of several databases, including PubMed, Web of Science, CNKI, and Wanfang database, to discover studies on herbal formulas that were effective in slowing the progression of DN. The names of the plants covered in the review have been checked at MPNS (http://mpns.kew.org).

RESULTS

This review demonstrates the superior total clinical effective rate of combining Chinese herbal medicines with Western medicines over the use of Western medicines alone, as evidenced by summarizing the results of several clinical trials. Furthermore, the review highlights the nephroprotective effects of seven frequently used herbs exerting beneficial effects such as podocyte repair, anti-fibrosis of renal tissues, and regulation of glucose and lipid metabolism through multiple signaling pathways in the treatment of DN.

CONCLUSIONS

The potential of herbs in treating DN is evident from their excellent effectiveness and the ability of different herbs to target various symptoms of the condition. However, limitations arise from the deficiencies in interfacing with objective bioindicators, which hinder the integration of herbal therapies into modern medical practice. Further research is warranted to address these limitations and enhance the compatibility of herbal therapies with contemporary medical standards.

Molecular mechanisms underlying cisplatin-induced nephrotoxicity and the potential ameliorative effects of essential oils: A comprehensive review

Since the Middle Ages, essential oils (EO) have been widely used for bactericidal, virucidal, fungicidal, insecticidal, medicinal and cosmetic applications, nowadays in pharmaceutical, agricultural and food industries. Recently, EO have emerged as promising adjuvant therapies to mitigate the toxicities induced by anti - cancerous drugs; among them cisplatin induced renal damage amelioration remain remarkable. Cisplatin (cis-diaminedichloroplatinum II, CDDP) is renowned as one of the most effective anti-neoplastic agents, widely used as a broad-spectrum anti-tumor agent for various solid tumors. However, its clinical use is hampered by several side effects, notably nephrotoxicity and acute kidney injury, which arise from the accumulation of CDDP in the proximal tubular epithelial cells (PTECs). To better understand and analyze the molecular mechanisms of CDDP-induced renal damage, it is crucial to investigate potential interventions to protect against cisplatin-mediated nephrotoxicity. These EO have shown the ability to counteract oxidative stress, reduce inflammation, prevent apoptosis, and exert estrogenic effects, all contributing to renal protection. In this review, we have made an effort to summarize the molecular mechanisms and exploring new interventions by which we can pave the way for safer and more effective cancer management in the future.

The role of C5a receptors in autoimmunity

The complement system is an essential component of the innate immune response and plays a vital role in host defense and inflammation. Dysregulation of the complement system, particularly involving the anaphylatoxin C5a and its receptors (C5aR1 and C5aR2), has been linked to several autoimmune diseases, indicating the potential for targeted therapies. C5aR1 and C5aR2 are seven-transmembrane receptors with distinct signaling mechanisms that play both partially overlapping and opposing roles in immunity. Both receptors are expressed on a broad spectrum of immune and non-immune cells and are involved in cellular functions and physiological processes during homeostasis and inflammation. Dysregulated C5a-mediated inflammation contributes to autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, epidermolysis bullosa acquisita, antiphospholipid syndrome, and others. Therefore, targeting C5a or its receptors may yield therapeutic innovations in these autoimmune diseases by reducing the recruitment and activation of immune cells that lead to tissue inflammation and injury, thereby exacerbating the autoimmune response. Clinical trials focused on the inhibition of C5 cleavage or the C5a/C5aR1-axis using small molecules or monoclonal antibodies hold promise for bringing novel treatments for autoimmune diseases into practice. However, given the heterogeneous nature of (systemic) autoimmune diseases, there are still several challenges, such as patient selection, optimal dosing, and treatment duration, that require further investigation and development to realize the full therapeutic potential of C5a receptor inhibition, ideally in the context of a personalized medicine approach. Here, we aim to provide a brief overview of the current knowledge on the function of C5a receptors, the involvement of C5a receptors in autoimmune disorders, the molecular mechanisms underlying C5a receptor-mediated autoimmunity, and the potential for targeted therapies to modulate their activity.

Differential expression profile of urinary exosomal microRNAs in patients with mesangial proliferative glomerulonephritis

OBJECTIVE

To investigate the differential expression profile of urinary exosomal microRNA (miRNA) in patients with mesangial proliferative glomerulonephritis (MsPGN) and healthy controls and their potential role in the pathogenesis of MsPGN.

METHODS

Urine specimens were collected from five MsPGN patients and five healthy controls, and differentially expressed miRNAs were screened using high-throughput sequencing technology. The sequenced urinary exosomal miRNAs were further investigated by quantitative real-time polymerase chain reaction (qRT-PCR) in a validation cohort (16 MsPGN patients and 16 healthy controls). Correlation and receiver operating characteristic (ROC) curve analyses were used to determine the association between clinical features and miRNA expression in MsPGN. Finally, fluorescence in situ hybridization was performed to detect miRNA expression in the renal tissues of MsPGN patients.

RESULTS

Five differentially expressed miRNAs (miR-125b-2-3p, miR-205-5p, let-7b-3p, miR-1262, and miR-548o-3p) were identified by qRT-PCR. The expression of these miRNAs correlated with ACR, 24hUpro, mAlb, UA, and combined yielded a ROC curve area of 0.916 in discriminating MsPGN patients from the controls. In addition, the expression of miR-205-5p, let-7b-3p, miR-1262, and miR-548o-3p was elevated in the MsPGN patient group, and miR-125b-2-3p was decreased in the MsPGN patient group.

CONCLUSIONS

Differential expression of urinary exosomal miRNAs may pose a risk of MsPGN and help distinguish MsPGN patients from controls. Certain miRNA expressions may be associated with disease progression, contributing to the epigenetic understanding of the pathophysiology of MsPGN.

Protective role of host complement system in Aspergillus fumigatus infection

Invasive aspergillosis (IA) is a life-threatening fungal infection for immunocompromised hosts. It is, therefore, necessary to understand the immune pathways that control this infection. Although the primary infection site is the lungs, aspergillosis can disseminate to other organs through unknown mechanisms. Herein we have examined the in vivo role of various complement pathways as well as the complement receptors C3aR and C5aR1 during experimental systemic infection by Aspergillus fumigatus, the main species responsible for IA. We show that C3 knockout (C3^-/-) mice are highly susceptible to systemic infection of A. fumigatus. Intriguingly, C4^-/- and factor B (FB)^-/- mice showed susceptibility similar to the wild-type mice, suggesting that either the complement pathways display functional redundancy during infection (i.e., one pathway compensates for the loss of the other), or complement is activated non-canonically by A. fumigatus protease. Our in vitro study substantiates the presence of C3 and C5 cleaving proteases in A. fumigatus. Examination of the importance of the terminal complement pathway employing C5^-/- and C5aR1^-/- mice reveals that it plays a vital role in the conidial clearance. This, in part, is due to the increased conidial uptake by phagocytes. Together, our data suggest that the complement deficiency enhances the susceptibility to systemic infection by A. fumigatus.

Interleukin-6 Downregulates the Expression of Vascular Endothelial-Cadherin and Increases Permeability in Renal Glomerular Endothelial Cells via the Trans-Signaling Pathway

The pathogenesis of IgA nephropathy (IgAN) is still unknown, but reportedly, interleukin 6 (IL-6) is involved in this process. However, its role in damaging glomerular endothelial cells is still unclear. Therefore, in this study, to clarify the mechanism of the pathogenesis of IgAN, we investigated the effect of IL-6 on the permeability of glomerular endothelial cells. A rat model of IgAN was established, and the animals divided into two groups, namely, the normal and IgAN groups. Glomerular endothelial cell injury was evaluated via electron microscopy. Furthermore, IL-6-induced changes in the permeability of human renal glomerular endothelial cells (HRGECs) were measured via trans-endothelial resistance (TEER) measurements and fluorescein isothiocyanate-dextran fluorescence. Furthermore, vascular endothelial-cadherin (VE-cadherin) was overexpressed to clarify the effect of IL-6 on HRGEC permeability, and to determine the pathway by which it acts. The classical signaling pathway was blocked by silencing IL-6R and the trans-signaling pathway was blocked by sgp30Fc. In IgAN rats, electron microscopy showed glomerular endothelial cell damage and western blotting revealed a significant increase in IL-6 expression, while VE-cadherin expression decreased significantly in the renal tissues. IL-6/IL-6R stimulation also significantly increased the permeability of HRGECs (p < 0.05). This effect was significantly reduced by VE-cadherin overexpression (p < 0.01). After IL-6R was silenced, IL-6/IL-6R still significantly reduced VE-cadherin expression and sgp30Fc blocked the trans-signaling pathway as well as the upregulation of IL-6/IL-6R-induced VE-cadherin expression. This suggests that IL-6 mainly acts via the trans-signaling pathway. IL-6 increased the permeability of HRGECs by decreasing the expression of VE-cadherin via the trans-signaling pathway.

Aqueous Extract and Polysaccharide of Aconiti Lateralis Radix Induce Apoptosis and G0/G1 Phase Cell Cycle Arrest by PI3K/AKT/mTOR Signaling Pathway in Mesangial Cells

Mesangial proliferative glomerulonephritis (MesPGN) is a common renal disease that lacks effective drug intervention. Aconiti Lateralis Radix (Fuzi), a natural Chinese medical herb, is found with significant therapeutic effects on various diseases in the clinic. However, its effects on MesPGN have not been reported. This study is aimed to discuss the therapeutic effects of the aqueous extract of Aconiti Lateralis Radix (ALR) and the polysaccharides of Aconiti Lateralis Radix (PALR) on MesPGN as well as the underlying mechanism. In this study, we, firstly, studied the anti-MesPGN mechanism of ALR and PALR. ALR and PALR inhibit the proliferation of the mesangial cells through the PI3K/AKT/mTOR pathway, induce the G0/G1 phase of block and apoptosis, inhibit the activity of Cyclin E and CDK2, increase the expression of Bax, cleaved caspase-8/caspase-8, and cleaved caspase-3/caspase-3 proteins, and effectively inhibit the growth of the mesangial cells. Overall, our data suggest that ALR and PALR may be potential candidates for MesPGN and that PALR is more effective than ALR.

Cytoprotective potentialities of carvacrol and its nanoemulsion against cisplatin-induced nephrotoxicity in rats: development of nano-encasulation form

Cisplatin (Cisp) is a widely distributed chemotherapeutic drug for cancers. Nephrotoxicity is one of the most common side effects of the use of this drug. Carvacrol (CV) is a common natural compound in essential oils and extracts of medicinal plants with potent in vivo and in vitro bioactivities. The work was extended to achieve the target of investigation of the protective potentialities of CV and its nanoemulsion as a cytoprotective drug against Cisp-induced nephrotoxicity in albino rats. CV-nanoemulsion was prepared by a hydrophilic surfactant polysorbate 80 (Tween 80) and deionized water. The TEM image of the particle distribution prepared nanoemulsion is mainly spherical in shape with particle size varying between 14 and 30 nm. Additionally, the Cisp administration caused the increasing of the levels of urea and creatinine in the blood and serum. These increasing of urea and creatinine levels caused consequently the turbulence of the oxidative stress as well as the rising of hs-CRP, IL-6, and TNF-α levels in the serum. Also, histopathological changes of the kidney tissue were observed. These changes back to normal by treatment with CV-nanoemulsion. Expression levels of nephrotoxicity-related genes including LGALS3, VEGF, and CAV1 in kidney tissue using qRT-PCR were measured. The results revealed that the expression of LGALS3, VEGF and CAV1 genes was highly significantly increased in only Cisp treated group when compared with other treated groups. While, these genes expressions were significantly decreased in Cisp + CV treated group when compared with Cisp treated rats (P < 0.001). In addition, there were no significant differences between Cisp + nano-CV treated group and both negative control and nanoemulsion alone groups but it was not significant. In addition, the Western blot of protein analysis results showed that the LGALS3 and CAV1 are highly expressed only in Cisp + CV treated group compared with other groups. There was no significant difference between Cisp + nano-CV treated animals and negative control for both mRNA and protein expression. Based on these results, CV was combined with calcium alginate; a more stable capsule is formed, allowing for the formation of a double wall in the microcapsule. These results supported the therapeutic effect of CV and its nano-emulsion as cytoprotective agents against Cisp nephrotoxicity.

In Vivo Pharmacodynamic Method to Assess Complement C5a Receptor Antagonist Efficacy

The complement C5a receptor 1 (C5aR1) has been studied as a potential therapeutic target for autoimmune and inflammatory diseases, with several drug candidates identified. Understanding the pharmacokinetics and pharmacodynamics of a drug candidate is a crucial preclinical step that allows for a greater understanding of a compound's in vivo biodistribution and target engagement to assist in clinical dose selection and dosing frequency. However, few in vivo pharmacodynamic methods have been described for C5a inhibitors. In this study, we, therefore, developed a complete in vivo pharmacodynamic assay in mice and applied this method to the peptide-based C5aR1 antagonists PMX53 and JPE-1375. Intravenous administration of recombinant mouse C5a induced rapid neutrophil mobilization and plasma TNF elevation over a 60 min period. By using C5a receptor-deficient mice, we demonstrated that this response was driven primarily through C5aR1. We next identified using this model that both PMX53 and JPE-1375 have similar in vivo working doses that can inhibit C5aR1-mediated neutrophilia and cytokine production in a dose as low as 1 mg/kg following intravenous injection. However, the in vivo active duration for PMX53 lasted for up to 6 h, significantly longer than that for JPE-1375 (<2 h). Pharmacokinetic analysis demonstrated rapid plasma distribution and elimination of both compounds, although PMX53 had a longer half-life, which allowed for the development of an accurate pharmacokinetic/pharmacodynamic model. Overall, our study developed a robust in vivo pharmacodynamic model for C5aR1 inhibitors in mice that may assist in preclinical translational studies of therapeutic drug candidates targeting C5a and its receptors.

Complement C5 inhibition protects against hemolytic anemia and acute kidney injury in anthrax peptidoglycan-induced sepsis in baboons

Late-stage anthrax infections are characterized by dysregulated immune responses and hematogenous spread of Bacillus anthracis, leading to extreme bacteremia, sepsis, multiple organ failure, and, ultimately, death. Despite the bacterium being nonhemolytic, some fulminant anthrax patients develop a secondary atypical hemolytic uremic syndrome (aHUS) through unknown mechanisms. We recapitulated the pathology in baboons challenged with cell wall peptidoglycan (PGN), a polymeric, pathogen-associated molecular pattern responsible for the hemostatic dysregulation in anthrax sepsis. Similar to aHUS anthrax patients, PGN induces an initial hematocrit elevation followed by progressive hemolytic anemia and associated renal failure. Etiologically, PGN induces erythrolysis through direct excessive activation of all three complement pathways. Blunting terminal complement activation with a C5 neutralizing peptide prevented the progressive deposition of membrane attack complexes on red blood cells (RBC) and subsequent intravascular hemolysis, heme cytotoxicity, and acute kidney injury. Importantly, C5 neutralization did not prevent immune recognition of PGN and shifted the systemic inflammatory responses, consistent with improved survival in sepsis. Whereas PGN-induced hemostatic dysregulation was unchanged, C5 inhibition augmented fibrinolysis and improved the thromboischemic resolution. Overall, our study identifies PGN-driven complement activation as the pathologic mechanism underlying hemolytic anemia in anthrax and likely other gram-positive infections in which PGN is abundantly represented. Neutralization of terminal complement reactions reduces the hemolytic uremic pathology induced by PGN and could alleviate heme cytotoxicity and its associated kidney failure in gram-positive infections.

Extracellular Vesicles Derived from Endothelial Progenitor Cells Protect Human Glomerular Endothelial Cells and Podocytes from Complement- and Cytokine-Mediated Injury

Glomerulonephritis are renal inflammatory processes characterized by increased permeability of the Glomerular Filtration Barrier (GFB) with consequent hematuria and proteinuria. Glomerular endothelial cells (GEC) and podocytes are part of the GFB and contribute to the maintenance of its structural and functional integrity through the release of paracrine mediators. Activation of the complement cascade and pro-inflammatory cytokines (CK) such as Tumor Necrosis Factor α (TNF-α) and Interleukin-6 (IL-6) can alter GFB function, causing acute glomerular injury and progression toward chronic kidney disease. Endothelial Progenitor Cells (EPC) are bone-marrow-derived hematopoietic stem cells circulating in peripheral blood and able to induce angiogenesis and to repair injured endothelium by releasing paracrine mediators including Extracellular Vesicles (EVs), microparticles involved in intercellular communication by transferring proteins, lipids, and genetic material (mRNA, microRNA, lncRNA) to target cells. We have previously demonstrated that EPC-derived EVs activate an angiogenic program in quiescent endothelial cells and renoprotection in different experimental models. The aim of the present study was to evaluate in vitro the protective effect of EPC-derived EVs on GECs and podocytes cultured in detrimental conditions with CKs (TNF-α/IL-6) and the complement protein C5a. EVs were internalized in both GECs and podocytes mainly through a L-selectin-based mechanism. In GECs, EVs enhanced the formation of capillary-like structures and cell migration by modulating gene expression and inducing the release of growth factors such as VEGF-A and HGF. In the presence of CKs, and C5a, EPC-derived EVs protected GECs from apoptosis by decreasing oxidative stress and prevented leukocyte adhesion by inhibiting the expression of adhesion molecules (ICAM-1, VCAM-1, E-selectin). On podocytes, EVs inhibited apoptosis and prevented nephrin shedding induced by CKs and C5a. In a co-culture model of GECs/podocytes that mimicked GFB, EPC-derived EVs protected cell function and permeselectivity from inflammatory-mediated damage. Moreover, RNase pre-treatment of EVs abrogated their protective effects, suggesting the crucial role of RNA transfer from EVs to damaged glomerular cells. In conclusion, EPC-derived EVs preserved GFB integrity from complement- and cytokine-induced damage, suggesting their potential role as therapeutic agents for drug-resistant glomerulonephritis.

Pathogenesis of arrhythmogenic cardiomyopathy: role of inflammation

Arrhythmogenic cardiomyopathy (AC) is an inherited disease characterized by progressive breakdown of heart muscle, myocardial tissue death, and fibrofatty replacement. In most cases of AC, the primary lesion occurs in one of the genes encoding desmosomal proteins, disruption of which increases membrane fragility at the intercalated disc. Disrupted, exposed desmosomal proteins also serve as epitopes that can trigger an autoimmune reaction. Damage to cell membranes and autoimmunity provoke myocardial inflammation, a key feature in early stages of the disease. In several preclinical models, targeting inflammation has been shown to blunt disease progression, but translation to the clinic has been sparse. Here we review current understanding of inflammatory pathways and how they interact with injured tissue and the immune system in AC. We further discuss the potential role of immunomodulatory therapies in AC.

Neutrophil extracellular trap-associated molecules: a review on their immunophysiological and inflammatory roles

Neutrophil extracellular traps (NETs) are a defense mechanism against pathogens. They are composed of DNA and various proteins and have the ability to hinder microbial spreading and survival. However, NETs are not only related to infections but also participate in sterile inflammatory events. In addition to DNA, NETs contain histones, serine proteases, cytoskeletal proteins and antimicrobial peptides, all of which have immunomodulatory properties that can augment or decrease the inflammatory response. Extracellular localization of these molecules alerts the immune system of cellular damage, which is triggered by recognition of damage-associated molecular patterns (DAMPs) through specific pattern recognition receptors. However, not all of these molecules are DAMPs and may have other immunophysiological properties in the extracellular space. The release of NETs can lead to production of pro-inflammatory cytokines (due to TLR2/4/9 and inflammasome activation), the destruction of the extracellular matrix, activation of serine proteases and of matrix metallopeptidases (MMPs), modulation of cellular proliferation, induction of cellular migration and adhesion, promotion of thrombogenesis and angiogenesis and disruption of epithelial and endothelial permeability. Understanding the dynamics of NET-associated molecules, either individually or synergically, will help to unravel their role in inflammatory events and open novel perspectives for potential therapeutic targets. We here review molecules contained within NETS and their immunophysiological roles.

A novel potential target of IL-35-regulated JAK/STAT signaling pathway in lupus nephritis

BACKGROUND

In this study, we have investigated the potential regulatory mechanisms of IL-35 to relieve lupus nephritis (LN) through regulating Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway in mesangial cells.

RESULTS

Among 105 significant differentially expressed proteins (DEPs) between juvenile systemic lupus erythematosus (JSLE) patients with LN and healthy controls, LAIR1, PDGFRβ, VTN, EPHB4, and EPHA4 were downregulated in JSLE-LN. They consist of an interactive network with PTPN11 and FN1, which involved in IL-35-related JAK/STAT signaling pathway. Besides, urinary LAIR1 was significantly correlated with JSLE-LN clinical parameters such as SLEDAI-2K, %CD19+ B, and %CD3+ T cells. Through bioinformatics analysis of co-immunoprecipitation with mass spectrometry results, including GO, KEGG, and STRING, five genes interacted with Lair1 were upregulated by IL-35, but only Myh10 was downregulated. Therefore, we presumed an interactive network among these DEPs, JAK/STAT, and IL-35. Moreover, the downregulated phosphorylated (p)-STAT3, p-p38 MAPK, and p-ERK, and the upregulated p-JAK2/p-STAT1/4 in IL-35 overexpressed mesangial cells, and RNA-sequencing results validated the potential regulatory mechanisms of IL-35 in alleviating JSLE-LN disease. Moreover, the relieved histopathological features of nephritis including urine protein and leukocyte scores, a decreased %CD90+ αSMA+ mesangial cells and pro-inflammatory cytokines, the inactivated JAK/STAT signals and the significant upregulated Tregs in spleen, thymus and peripheral blood were validated in Tregs and IL-35 overexpression plasmid-treated lupus mice.

CONCLUSIONS

Our study provided a reference proteomic map of urinary biomarkers for JSLE-LN and elucidated evidence that IL-35 may regulate the interactive network of LAIR1-PTPN11-JAK-STAT-FN1 to affect JAK/STAT and MAPK signaling pathways to alleviate inflammation in JSLE-LN. This finding may provide a further prospective mechanism for JSLE-LN clinical treatment.

Network Pharmacology-Based Dissection of the Anti-diabetic Mechanism of Lobelia chinensis

Diabetes mellitus (DM) is a chronic inflammatory disease, and the rapidly increasing DM is becoming a major problem of global public health. Traditional Chinese medicine (TCM) has a long history of treating diabetes. It has been developed and utilized because of its good efficacy and no toxic side effects. Lobelia chinensis is a traditional whole grass herbal. With the continuous deepening of pharmacological research on TCM, the active ingredients of L. chinensis are continuously revealed, which contained the alkaloids, flavonoids, flavonoid glycosides and amino acids that have the good effects of anti-inflammatory, anti-viral and anti-diabetic. In order to further explore the targets of active ingredients and its anti-diabetic mechanism, a feasible network pharmacology analysis model based on chemical, pharmacokinetic and pharmacological data was developed by network construction method to clarify the anti-diabetic mechanism of L. chinensis. The present study conducted by gas chromatography–mass spectrometer (GC/MS), which identified 208 metabolites of L. chinensis, of which 23 ingredients may have effective pharmacological effects after absorption, distribution, metabolism, and excretion (ADME) screening. Network pharmacological analysis on the active ingredients revealed that 5-hydroxymethylfurfural in L. chinensis affects the insulin resistance signaling pathway by acting on GSK3B, TNF, and MAPK1, acacetin affects the diabetic pathway by acting on INSR, DPP4, and GSK3B, that regulate type 2 diabetes, non-insulin-dependent DM, and inflammatory diseases. These results successfully indicated the potential anti-diabetic mechanism of the active ingredients of L. chinensis.

Assessment of blood-brain barrier integrity and neuroinflammation in preeclampsia

BACKGROUND

Although blood-brain barrier integrity is intact under normal pregnancy conditions, animal studies suggest that blood-brain barrier impairment occurs in preeclampsia. Yet, human data are limited, and the integrity of the blood-brain barrier has not been assessed in women with preeclampsia.

OBJECTIVE

We sought to test the hypothesis that the integrity of the blood-brain barrier is impaired and that neuroinflammation is increased in women with preeclampsia.

STUDY DESIGN

We performed an observational case-control study in pregnant women >24 weeks gestation who underwent spinal anesthesia for elective cesarean delivery or combined spinal epidural analgesia for labor. Cases were women with preeclampsia, and control subjects were women with either healthy pregnancy, chronic hypertension, or gestational hypertension. Paired samples of blood, urine, and cerebrospinal fluid were collected from each subject before delivery. We measured albumin, C5a, C5b-9, tumor necrosis factor-α, and interleukin-6 concentrations in plasma and cerebrospinal fluid, and albumin, C5a, and C5b-9 concentrations in urine, using colorimetric or enzyme-linked immunosorbent assays. The ratio of albumin in cerebrospinal fluid to plasma (Qalb) was used as a surrogate for maternal blood-brain barrier integrity. Cerebrospinal fluid concentrations of C5a, C5b-9, tumor necrosis factor-α, and interleukin-6 were used as surrogate markers of neuroinflammation. Differences in Qalb and cerebrospinal fluid protein concentrations between groups were assessed by nonparametric test of medians.

RESULTS

Forty-eight subjects were enrolled, which included 16 cases with preeclampsia, 16 control subjects with healthy pregnancy, and 16 control subjects with either chronic or gestational hypertension. Qalb values were not increased in preeclampsia cases compared with healthy or hypertensive control subjects (Qalb median, 3.5 [interquartile range, 2.9-5.1] vs 3.9 [interquartile range, 3.0-4.8] vs 3.9 [interquartile range, 3.0-4.8]; P=.78]. Moreover, Qalb values were not increased in the subset of women with preeclampsia with severe features (n=8) compared with those without severe features (n=8; Qalb median, 3.5 [interquartile range, 3.3-4.9] vs 3.7 [interquartile range, 2.3-5.5]; P=.62]. Cerebrospinal fluid concentrations of C5a, C5b-9, tumor necrosis factor-α and interleukin-6 were not increased in cases of preeclampsia, compared with control subjects with either healthy pregnancy, chronic hypertension, or gestational hypertension (P>.05, all comparisons). In contrast to the negative findings in cerebrospinal fluid, plasma concentrations of both C5b-9 and interleukin-6 and urine concentrations of C5a and C5b-9 were increased in cases of preeclampsia.

CONCLUSION

Through measurements of albumin, complement proteins, and cytokines in paired samples of blood and cerebrospinal fluid at the time of delivery, we found no evidence of blood-brain barrier impairment or neuroinflammation in preeclampsia. Larger studies that will investigate a wider range of proteins are suggested to validate our findings.

Effects of Qi Teng Xiao Zhuo granules on circRNA expression profiles in rats with chronic glomerulonephritis

Objectives: To screen and study circular RNA (circRNA) expression profiles in QTXZG-mediated treatment of chronic glomerulonephritis (CGN) induced by adriamycin in rats and to research the possible roles and molecular mechanisms of QTXZG. Materials and methods: Next-generation RNA sequencing was used to identify circRNA expression profiles in CGN after QTXZG treatment compared with a CGN model group and a control group. Bioinformatics analysis was performed to predict potential target miRNAs and mRNAs. GO and pathway analyses for potential target mRNAs were used to explore the potential roles of differentially expressed (DE) circRNAs. Results: We identified 31 and 21 significantly DE circRNAs between the model group vs the control group and the model group vs the QTXZG group, respectively. Four circRNAs that resulted from the establishment of the CGN model were reversed following treatment with QTXZG. Further analysis revealed that these four circRNAs may play important roles in the development of CGN. Conclusions: This study elucidated the comprehensive expression profile of circRNAs in CGN rats after QTXZG treatment for the first time. Analysis of the circRNA-miRNA-mRNA-ceRNA network to determine potential function provided a comprehensive understanding of circRNAs that may be involved in the development of CGN. The current study indicated that therapeutic effects of QTXZG on CGN may be due to regulation of circRNA expression.

An experimental study of exenatide effects on renal injury in diabetic rats1

PURPOSE

To investigate the effects of exenatide on renal injury in streptozotocin-induced diabetic rats.

METHODS

Fifty SD rats were randomly divided into normal control, model, exenatide-1, exenatide-2 and exenatide-3 groups, 10 rats in each group. The diabetic nephropathy model was constructed in later 4 groups. Then, the later 3 groups were treated with 2, 4 and 8 μg/kg exenatide for 8 weeks, respectively. The serum and urine biochemical indexes and oxidative stress and inflammatory indexes in renal tissue were determined.

RESULTS

Compared to the model group, in exenatide-3 group the serum fasting plasma glucose and hemoglobin A1c levels were significantly decreased, the fasting insulin level was significantly increased, the renal index and blood urea nitrogen, serum creatinine and 24 h urine protein levels were significantly decreased, the renal tissue superoxide dismutase and glutathione peroxidase levels were significantly increased, the malondialdehyde level was significantly decreased, and the renal tissue tumor necrosis factor alpha, interleukin 6, hypersensitive C-reactive protein and chemokine (C-C motif) ligand 5 levels were significantly decreased P<0.05).

CONCLUSIONS

Exenatide can mitigate the renal injury in diabetic rats. The mechanisms may be related to its resistance of oxidative stress and inflammatory response in renal tissue.

Association of Serum Levels of Calcitonin Gene-related Peptide and Cytokines during Migraine Attacks

Background:

During a migraine attack, trigeminal activation results in the release of calcitonin gene-related peptide (CGRP), which stimulates the release of inflammatory cytokines playing an important role in migraine.

Objective:

We analyze the relation between CGRP and cytokines during attacks to explore the possible mechanism of migraine.

Materials and Methods:

Migraine patients and healthy control were recruited at the Department of Neurology, the Sixth People's Hospital of Fuyang City, between March 2018 and July 2018. The protein levels of interleukin (IL)-1β, IL-2, IL-6, IL-10, tumor necrosis factor-alpha (TNF-α), and CGRP were determined from the sera of patients with migraine and control subjects by enzyme-linked immunosorbent assay kits. Spearman's rank correlation coefficient was also determined to calculate the correlation between CGRP and inflammatory factors levels.

Results:

The level of IL-1β, IL-6, TNF-α, and CGRP in migraine group were significantly higher than normal group (P < 0.05). The level of CGRP was significantly correlated with IL-1 β (r = 0.30, P < 0.05) and IL-6 (r = 0.94, P < 0.05), but not significantly correlated with IL-2 (r =−0.047, P = 0.75), IL-10 (r = 0.12, P = 0.43), and TNF-α (r = 0.05, P = 0.72).

Conclusions:

In our study, we found migraine patients had a higher IL-6, IL-1β, and TNF level than healthy controls and the level of CGRP was related significantly with the level of IL-1β and IL-6. In conclusion, our results suggest that IL-1β and IL-6 may be involved in the pathogenesis of migraine attacks and CGRP related with the secretion of cytokines.

Pseudane-VII Isolated from Pseudoalteromonas sp. M2 Ameliorates LPS-Induced Inflammatory Response In Vitro and In Vivo

The ocean is a rich resource of flora, fauna, food, and biological products. We found a wild-type bacterial strain, Pseudoalteromonas sp. M2, from marine water and isolated various secondary metabolites. Pseudane-VII is a compound isolated from the Pseudoalteromonas sp. M2 metabolite that possesses anti-melanogenic activity. Inflammation is a response of the innate immune system to microbial infections. Macrophages have a critical role in fighting microbial infections and inflammation. Recent studies reported that various compounds derived from natural products can regulate immune responses including inflammation. However, the anti-inflammatory effects and mechanism of pseudane-VII in macrophages are still unknown. In this study, we investigated the anti-inflammatory effects of pseudane-VII. In present study, lipopolysaccharide (LPS)-induced nitric oxide (NO) production was significantly decreased by pseudane-VII treatment at 6 μM. Moreover, pseudane-VII treatment dose-dependently reduced mRNA levels of pro-inflammatory cytokines including inos, cox-2, il-1β, tnf-α, and il-6 in LPS-stimulated macrophages. Pseudane-VII also diminished iNOS protein levels and IL-1β secretion. In addition, Pseudane-VII elicited anti-inflammatory effects by inhibiting ERK, JNK, p38, and nuclear factor (NF)-κB-p65 phosphorylation. Consistently, pseudane-VII was also shown to inhibit the LPS-stimulated release of IL-1β and expression of iNOS in mice. These results suggest that pseudane-VII exerted anti-inflammatory effects on LPS-stimulated macrophage activation via inhibition of ERK, JNK, p38 MAPK phosphorylation, and pro-inflammatory gene expression. These findings may provide new approaches in the effort to develop anti-inflammatory therapeutics.

Diabetic nephropathy: New insights into established therapeutic paradigms and novel molecular targets

Diabetic nephropathy is one of the most prevalent microvascular complication in patients suffering from diabetes and is reported to be the major cause of renal failure when compared to any other kidney disease. Currently, available therapies provide only symptomatic relief and unable to treat the underlying pathophysiology of diabetic nephropathy. This review will explore new insights into the established therapeutic paradigms targeting oxidative stress, inflammation and endoplasmic reticulum stress with the focus on recent clinical developments. Apart from this, the involvement of novel cellular and molecular mechanisms including the role of endothelin-receptor antagonists, Wnt signaling pathway, epigenetics and micro RNA is also discussed so that key molecular switches involved in the pathogenesis of diabetic nephropathy can be identified. Elucidating new molecular pathways will help in the development of novel therapeutics for the prevention and treatment of diabetic nephropathy.

Interleukin-6 Signaling Pathway and Its Role in Kidney Disease: An Update

Interleukin-6 (IL-6) is a pleiotropic cytokine that not only regulates the immune and inflammatory response but also affects hematopoiesis, metabolism, and organ development. IL-6 can simultaneously elicit distinct or even contradictory physiopathological processes, which is likely discriminated by the cascades of signaling pathway, termed classic and trans-signaling. Besides playing several important physiological roles, dysregulated IL-6 has been demonstrated to underlie a number of autoimmune and inflammatory diseases, metabolic abnormalities, and malignancies. This review provides an overview of basic concept of IL-6 signaling pathway as well as the interplay between IL-6 and renal-resident cells, including podocytes, mesangial cells, endothelial cells, and tubular epithelial cells. Additionally, we summarize the roles of IL-6 in several renal diseases, such as IgA nephropathy, lupus nephritis, diabetic nephropathy, acute kidney injury, and chronic kidney disease.