Exosome-mediated renal protection: Halting the progression of fibrosis

Renal fibrosis is a complex and multifactorial process that involves inflammation, cell proliferation, collagen, and fibronectin deposition in the kidney, ultimately leading to chronic kidney disease and even end-stage renal disease. The main goal of treatment is to slow down or halt the progression of fibrosis and to improve or preserve kidney function. Despite significant progress made in understanding the underlying mechanisms of renal fibrosis, current therapies have limited renal protection as the disease progresses. Exosomes derived from stem cells are a newer area of research for the treatment of renal fibrosis. Exosomes as nano-sized extracellular vesicles carry proteins, lipids, and nucleic acids, which can be taken up by local or distant cells, serving as mediators of intercellular communication and as drug delivery vehicles. Exosomes deliver molecules that reduce inflammation, renal fibrosis and extracellular matrix protein production, and promote tissue regeneration in animal models of kidney disease. Additionally, they have several advantages over stem cells, such as being non-immunogenic, having low risk of tumor formation, and being easier to produce and store. This review describes the use of natural and engineered exosomes containing therapeutic agents capable of mediating anti-inflammatory and anti-fibrotic processes during both acute kidney injury and chronic kidney disease. Exosome-based therapies will be compared with stem cell-based treatments for tissue regeneration, with a focus on renal protection. Finally, future directions and strategies for improving the therapeutic efficacy of exosomes are discussed.

IGF2BP3/NCBP1 complex inhibits renal tubular senescence through regulation of CDK6 mRNA stability

Renal aging and the subsequent rise in kidney-related diseases are attributed to senescence in renal tubular epithelial cells (RTECs). Our study revealed that the abnormal expression of insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), a reader of RNA N6-methyladenosine, is critically involved in cisplatin-induced renal tubular senescence. In cisplatin-induced senescence of RTECs, the promoter activity and transcription of IGF2BP3 is markedly suppressed. It was due to the down regulation of MYC proto-oncogene (MYC), which regulates IGF2BP3 transcription by binding to the putative site at 1852-1863 of the IGF2BP3 promoter. Overexpression of IGF2BP3 ameliorated cisplatin-induced renal tubular senescence in vitro. Mechanistic studies revealed that IGF2BP3 inhibits cellular senescence in RTECs by enhancing cyclin-dependent kinase 6 (CDK6) mRNA stability and increasing its expression. The inhibition effect of IGF2BP3 on tubular senescence is partially reversed by the knockdown of CDK6. Further, IGF2BP3 recruits nuclear cap binding protein subunit 1 (NCBP1) and inhibits CDK6 mRNA decay, by recognizing m6A modification. Specifically, IGF2BP3 recognizes m6A motif "GGACU" at nucleotides 110-114 in the 5' untranslated region (UTR) field of CDK6 mRNA. The involvement of IGF2BP3/CDK6 in alleviating tubular senescence was confirmed in a cisplatin-induced acute kidney injury (AKI)-to-chronic kidney disease (CKD) model. Clinical data also suggests an age-related decrease in IGF2BP3 and CDK6 levels in renal tissue or serum samples from patients. These findings suggest that IGF2BP3/CDK6 may be a promising target in cisplatin-induced tubular senescence and renal failure.

Exosomes on the development and progression of renal fibrosis

Renal fibrosis is a prevalent pathological alteration that occurs throughout the progression of primary and secondary renal disorders towards end-stage renal disease. As a complex and irreversible pathophysiological phenomenon, it includes a sequence of intricate regulatory processes at the molecular and cellular levels. Exosomes are a distinct category of extracellular vesicles that play a crucial role in facilitating intercellular communication. Multiple pathways are regulated by exosomes produced by various cell types, including tubular epithelial cells and mesenchymal stem cells, in the context of renal fibrosis. Furthermore, research has shown that exosomes present in bodily fluids, including urine and blood, may be indicators of renal fibrosis. However, the regulatory mechanism of exosomes in renal fibrosis has not been fully elucidated. This article reviewed and analysed the various mechanisms by which exosomes regulate renal fibrosis, which may provide new ideas for further study of the pathophysiological process of renal fibrosis and targeted treatment of renal fibrosis with exosomes.

Association between serum chloride levels and estimated glomerular filtration rate among US adults: evidence from NHANES 1999-2018

PURPOSE

Chloride, the predominant anion in extracellular fluid from humans, is essential to maintaining homeostasis. One important metric for thoroughly assessing kidney function is the estimated glomerular filtration rate (eGFR). However, the relationship between variations in serum chloride concentration and eGFR in general populations has been poorly studied. Therefore, the purpose of this study is to elucidate the correlation between serum chloride levels and eGFR within the United States' adult population.

METHODS

This cohort study was conducted using data from the National Health and Nutrition Examination Survey (NHANES), which covered the years 1999-2018. We employed multiple linear regression analysis and subgroup analysis to evaluate the correlation between serum chloride concentration and eGFR. To examine the nonlinear association between serum chloride levels and eGFR, restricted cubic spline analyses were employed.

RESULTS

Data from 49,008 participants in this cohort study were used for the chloride analysis. In the comprehensively adjusted model, a noteworthy inverse relationship was discovered between chloride plasma concentration and eGFR. Restricted cubic spline analyses revealed a significant nonlinear relationship between chloride levels and eGFR (P for overall < 0.001 and P for nonlinear < 0.001). A significant interaction was observed between eGFR and plasma chloride concentration (all P < 0.001 for interaction) among the subgroups characterized by sex, household income to poverty ratio, BMI, hypertension, and diabetes.

CONCLUSION

Our findings suggest that higher levels of chloride plasma concentration were linked to decreased eGFR. These findings underscore the significance of monitoring chloride plasma concentration as a potential indicator for identifying individuals at risk of developing chronic kidney disease (CKD).

Identification of natriuretic peptide receptor A-related gene expression signatures in podocytes in vivo reveals baseline control of protective pathways

Natriuretic peptide receptor-A (NPR-A) is the principal receptor for the natriuretic peptides atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). Targeted deletion of NPR-A in mouse glomerular podocytes significantly enhances renal injury in vivo in the DOCA-salt experimental model. It was therefore hypothesized that natriuretic peptides exert a direct protective effect on glomerular barrier integrity through activation of NPR-A and modulation of gene expression patterns in podocytes. Green fluorescence-positive podocytes from mice with a conditional deletion of Npr1 encoding NPR-A were isolated by fluorescence-activated cell sorting (FACS). Differentially expressed genes (DEGs) in podocytes were identified by RNA sequencing of podocytes from wild-type and NPR-A-deleted mice. Enrichment analysis was performed on the DEGs using Gene Ontology (GO) terms. Identified transcripts were validated by real-time PCR and ELISA of cultured isolated human and mouse glomeruli. In addition, the effect of natriuretic peptides on podocyte migration was investigated by measuring the outgrowth of podocytes from cultured glomeruli. A total of 158 DEGs were identified with 81 downregulated DEGs and 77 upregulated DEGs in Npr1-deficient podocytes. Among the downregulated genes were protein S and semaphorin 3G, which are known to have protective effects in podocytes. Protein S was also expressed in and secreted from isolated human glomeruli. GO enrichment analysis revealed that the upregulated DEGs in NPR-A deficient podocytes were associated with cell migration and motility. In line, BNP significantly decreased podocyte outgrowth from cultured glomeruli. In conclusion, endogenous levels of natriuretic peptides in mice support baseline protective pathways at glomerular podocytes such as protein S and suppress podocyte migration.NEW & NOTEWORTHY A combination of fluorescence-activated cell sorting and RNA sequencing identified 158 changed gene products in adult mouse kidneys with and without podocyte-specific deletion of the natriuretic peptide receptor A. Downregulated products included protein S and semaphorin 3G, both with proven renoprotective impact, whereas upregulated products were related to mobility of podocytes. Protein S was produced and released from human and murine isolated glomeruli, and atrial natriuretic peptide (ANP) led to decreased migration of podocytes.

TRIM65 deficiency alleviates renal fibrosis through NUDT21-mediated alternative polyadenylation

Chronic kidney disease (CKD) is a major global health concern and the third leading cause of premature death. Renal fibrosis is the primary process driving the progression of CKD, but the mechanisms behind it are not fully understood, making treatment options limited. Here, we find that the E3 ligase TRIM65 is a positive regulator of renal fibrosis. Deletion of TRIM65 results in a reduction of pathological lesions and renal fibrosis in mouse models of kidney fibrosis induced by unilateral ureteral obstruction (UUO)- and folic acid. Through screening with a yeast-hybrid system, we identify a new interactor of TRIM65, the mammalian cleavage factor I subunit CFIm25 (NUDT21), which plays a crucial role in fibrosis through alternative polyadenylation (APA). TRIM65 interacts with NUDT21 to induce K48-linked polyubiquitination of lysine 56 and proteasomal degradation, leading to the inhibition of TGF-β1-mediated SMAD and ERK1/2 signaling pathways. The degradation of NUDT21 subsequently altered the length and sequence content of the 3'UTR (3'UTR-APA) of several pro-fibrotic genes including Col1a1, Fn-1, Tgfbr1, Wnt5a, and Fzd2. Furthermore, reducing NUDT21 expression via hydrodynamic renal pelvis injection of adeno-associated virus 9 (AAV9) exacerbated UUO-induced renal fibrosis in the normal mouse kidneys and blocked the protective effect of TRIM65 deletion. These findings suggest that TRIM65 promotes renal fibrosis by regulating NUDT21-mediated APA and highlight TRIM65 as a potential target for reducing renal fibrosis in CKD patients.

Chronic alcohol consumption aggravates acute kidney injury through integrin β1/JNK signaling

Alcohol abuse is one of the major public health problems in the world and is associated with various health conditions. However, little is known about the effect of alcohol consumption on acute kidney injury (AKI). In this study, we demonstrate that chronic and binge alcohol feeding with a Lieber-DeCarli diet containing 5 % ethanol for 10 days, followed by a single dose of 31.5 % ethanol by gavage, aggravated AKI after ischemia-reperfusion injury (IRI) in female, but not in male, mice. Kidney dysfunction, histopathology and tubular cell apoptosis were more severe in EtOH-fed female mice after IRI, compared to pair-fed controls. RNA sequencing and experimental validation uncovered that activation of integrin β1 and its downstream c-Jun NH2-terminal kinase (JNK) aggravated AKI in EtOH-fed mice. Knockdown of integrin β1 inhibited JNK phosphorylation and alleviated AKI in EtOH-fed mice, whereas activation of integrin β1 by agonist antibody increased JNK phosphorylation, worsened renal histological injury and tubular cell apoptosis, and aggravated kidney dysfunction. In vitro, activation of integrin β1 increased JNK phosphorylation and induced tubular epithelial cell apoptosis. The detrimental effect of EtOH feeding was primarily mediated by acetaldehyde, as its levels were increased in the blood, liver and kidney of female mice fed with ethanol. Acetaldehyde per se activated integrin β1/JNK signaling and induced tubular cell apoptosis in vitro. These findings suggest that alcohol consumption increases vulnerability to AKI in female mice, which is probably mediated by acetaldehyde/integrin β1/JNK signaling cascade.

Histone methylation modification and diabetic kidney disease: Potential molecular mechanisms and therapeutic approaches (Review)

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease and end‑stage renal disease, and is characterized by persistent proteinuria and decreased glomerular filtration rate. Despite extensive efforts, the increasing incidence highlights the urgent need for more effective treatments. Histone methylation is a crucial epigenetic modification, and its alteration can destabilize chromatin structure, thereby regulating the transcriptional activity of specific genes. Histone methylation serves a substantial role in the onset and progression of various diseases. In patients with DKD, changes in histone methylation are pivotal in mediating the interactions between genetic and environmental factors. Targeting these modifications shows promise in ameliorating renal histological manifestations, tissue fibrosis and proteinuria, and represents a novel therapeutic frontier with the potential to halt DKD progression. The present review focuses on the alterations in histone methylation during the development of DKD, systematically summarizes its impact on various renal parenchymal cells and underscores the potential of targeted histone methylation modifications in improving DKD outcomes.

Poria cocos: traditional uses, triterpenoid components and their renoprotective pharmacology

Poria cocos and its surface layer of Poria cocos (Schw.) Wolf (Polyporaceae), are used in traditional Chinese medicine for its diuretic and renoprotective effects. Phytochemical studies have shown that lanostane and 3,4-seco-lanostane tetracyclic triterpenoids are the main components of P. cocos and its surface layer. Accumulating evidence shows that triterpenoid components in P. cocos and its surface layer contribute to their renoprotective effect. The surface layer of P. cocos showed a stronger diuretic effect than P. cocos. The ethanol extract of the surface layer and its components improved acute kidney injury, acute kidney injury-to-chronic kidney disease transition and chronic kidney disease such as diabetic kidney disease, nephrotic syndrome and tubulointerstitial nephropathy, and protected against renal fibrosis. It has been elucidated that P. cocos and its surface layer exert a diuretic effect and improve kidney diseases through a variety of molecular mechanisms such as aberrant pathways TGF-β1/Smad, Wnt/β-catenin, IκB/NF-κB and Keap1/Nrf2 signaling as well as the activation of renin-angiotensin system, matrix metalloproteinases, aryl hydrocarbon receptor and endogenous metabolites. These studies further confirm the renoprotective effect of P. cocos and its surface layer and provide a beneficial basis to its clinical use in traditional medicine.

The prognostic role of activation of the complement pathways in the progression of advanced IgA nephropathy to end-stage renal disease

INTRODUCTION

The role of complement system in late stage of IgA nephropathy (IgAN) remains unknown. We therefore investigated the effects of complement system on worsening kidney function in advanced (stage 4 CKD) IgAN.

METHODS

Renal specimens of 69 IgAN patients who underwent renal biopsy during stage 4 CKD between 2010 and 2021, were stained using immunofluorescence (IF) and immunohistochemistry (IHC) for glomerular complement components. The primary outcome was progression to end-stage renal disease (ESRD). Associations of complement components with baseline clinicopathological characteristics and outcomes were assessed using multivariable Cox regression and Spearman analyses.

RESULTS

During a median follow-up of 18.0 months, 26 (37.7%) patients progressed to ESRD and none died. C1q and C3 deposition were detected in 12 and 66 patients, respectively. Higher eGFR [hazards ratio (HR), 0.852, 95% confidence interval (CI), 0.756-0.959; P = 0.008], higher C3 intensity (HR, 2.955, 95%CI, 1.063-8.220; P = 0.038) and T1-2 score (HR, 2.576, 95%CI, 1.205-5.576, P = 0.015) were predictive of time to ESRD in CKD 4 stage IgAN. Significant expressions of C1q (P = 0.005), C4d (P < 0.001), factor B (P < 0.001), C3 (P = 0.042) and C5b-9 (P = 0.004) were identified in ESRD group than in non-ESRD group by IHC, while MBL expression was low. Although they were not associated with baseline 24 h-UP, higher factor B and C1q expressions were both correlated with a lower baseline eGFR (P < 0.001 and = 0.04, respectively) and the deterioration of kidney function during follow-up (P = 0.046 and 0.015, respectively).

CONCLUSION

Complement deposition in IgAN patients with stage 4 CKD portends a faster deterioration of kidney function. Activation of classical and alternative complement pathways plays a major role in this stage.

Liraglutide Ameliorates Renal Endothelial Dysfunction in Diabetic Rats Through the Inhibition of the Dll4/Notch2 Pathway

Purpose

The glucagon-like peptide-1 receptor agonist (GLP-1RA) is a pharmacological agent utilized for the treatment of diabetes, known for its significant reno protective effects. This study aims to investigate the impact of liraglutide, a representative GLP-1RA medication, on early endothelial dysfunction in diabetic rats and elucidate its underlying mechanisms.

Methods

The present study employed a high-fat, high-sugar diet in combination with a single intraperitoneal injection of streptozotocin (STZ) to establish an experimental rat model of diabetes. Subsequently, the therapeutic efficacy of liraglutide on renal injury in this model was evaluated using various doses.

Results

Compared to the DKD rats, the rats treated with Liraglutide exhibited significant reductions in levels of blood glucose (Glu), serum creatinine (Scr), and blood urea nitrogen (BUN) (P < 0.05). Furthermore, there was a dose-dependent decrease in urinary protein levels, including 24-hour urinary protein excretion rate and microalbuminuria (m-ALB), with higher doses demonstrating more pronounced therapeutic effects (P <0.05). In addition, treatment with Liraglutide effectively improved glomerular and interstitial damage, and suppressed the expression of CD31, CD34, and VE-cadherin associated with endothelial cell injury (P < 0.05). Furthermore, Liraglutide administration significantly increased nitric oxide (NO) production (P < 0.05). Moreover, Liraglutide treatment resulted in decreased expression of vascular endothelial growth factor (VEGF), Delta-like ligand-4(Dll4), and Notch2 protein in the Notch2 signaling pathway (P < 0.05).

Conclusion

The findings indicate that Liraglutide has a substantial effect on decreasing urinary protein excretion and improving vascular microinflammation, thus alleviating endothelial dysfunction in diabetic nephropathy. This observed mechanism can be attributed to the inhibition of the Dll4/Notch2 signaling pathway.

MiR-126 accelerates renal injury induced by UUO via inhibition PI3K/ IRS-1/ FAK signaling induced M2 polarization and endocytosis in macrophages

To investigate the role and molecular mechanism of miR-126 in unilateral ureteral occlusion (UUO). We used bioinformatics to analyse miRNAs specifically expressed in UUO. The mouse model of UUO was established using RAW264.7 cells cultured in vitro and in vivo. The mice were divided into control group, miR-126-NC (negative control) group and miR-126-KD (knockdown) group. Then the relative expression of miR-126 was detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), the renal fibrosis was detected by Masson staining, and the protein expression of CD68, collagen I and collagen III in the kidney was detected by immunofluorescence assay. Immunohistochemistry detects α-SMA expression. Moreover, Western blotting was performed to measure the expressions of p-PI3K, CD163, CD206, CD86, iNOS, IL-1β, p-FAK, p-Rac-1, p-IRS-1 and MMP9. The relative fluorescence intensity of F-actin and p-FAK was detected by immunofluorescence assay, and the phagocytosis ability of macrophages was determined by phagocytosis assay with fluorescent microspheres. Bioinformatics analysis reveals miR-126-specific overexpression in UUO. Successful transfection of miR-126-NC and miR-126-KD was confirmed by RT-PCR. The selective reduction of miR-126 was validated by Masson, immunohistochemistry and immunofluorescence staining to decrease the area of UUO-induced renal fibrosis and to lower the expression of CD68, α-SMA, collagen I, and collagen III. The reduction of iNOS expression may also be achieved with selective knockdown of miR-126, as verified by cell tests. enhances the phagocytic ability of macrophages and the expression of p-PI3K, CD206, p-FAK, F-actin, p-Rac-1, p-IRS-1 and MMP9. MiR-126 can inhibit the PI3K signaling pathway, promote M1 macrophage polarization, and suppress the activation of FAK and Rac-1, thus accelerating the progression of UUO.

Inhibition of CB1R in the Hypothalamic Paraventricular Nucleus Ameliorates Hypertension Through Wnt/β-Catenin/RAS Pathway

The hypothalamic paraventricular nucleus (PVN), as an important integrating center, plays a prominent role in the pathogenesis of hypertension, in maintaining the stability of cardiovascular activity through peripheral sympathetic nervous activity and secretion of various humoral factors. Acknowledging that the mechanistic targets of the endocannabinoid type 1 receptor (CB1R) are the key signaling systems involved in the regulation of hypertension, we sought to clarify whether inhibition of CB1R within the PVN ameliorates hypertension through Wnt/β-catenin/RAS pathway. Spontaneously hypertensive rats (SHRs) and Wistar Kyoto rats were randomly assigned to different groups and treated with bilateral PVN injections of AM251 (CB1R antagonist, 10 µg/h) or vehicle (artificial cerebrospinal fluid, aCSF) for four weeks. Bilateral PVN injections of AM251 significantly decreased the heart rate, the body weight and the mean arterial pressure in SHRs. AM251 lowered the expression of CB1R, Wnt3, active-β-catenin, p-IKKβ, RAS components, pro-inflammatory cytokines and elevated the expression level of Glycogen synthase kinase3β and Superoxide Dismutase in the PVN of hypertensive rats. Our findings suggest that inhibition of CB1R in the PVN ameliorates hypertension through Wnt/β-catenin/RAS pathway and broaden our current understanding of the pathological mechanism and clinical treatment of hypertension.

Inhibition of M2 tumor-associated macrophages polarization by modulating the Wnt/β-catenin pathway as a possible liver cancer therapy method

The problem of liver cancer is becoming increasingly important due to the epidemic of metabolic diseases and persistent high alcohol consumption. This determines great attention to the development and improvement of methods for early diagnosis and treatment of liver cancer. Huang et al presented a study in the World Journal of Gastroenterology, in which they showed that the use of the traditional Chinese medicine Calculus bovis (CB) can suppress tumor growth in mice by inhibiting M2 tumor-associated macrophages (TAM) through modulating the activity of the Wnt/β-catenin pathway. The interaction of CB components with the Wnt/β-catenin pathway, M2 TAM polarization, and tumor dynamics were studied using network pharmacology, transcriptomics, and molecular docking. It is now generally accepted that the polarization of TAM and the differentiation of the functions of M1 and M2 phagocytes are of great importance for the progression of neoplasms. It is assumed that M2 TAM promote proliferation and migration of tumor cells. Attempts to medicinally influence the Wnt/β-catenin pathway in order to modulate phagocyte polarization now belong to one of the most promising areas of immunotherapy of oncological diseases. Undoubtedly, the work of the Chinese authors deserves attention and further development.

Apigenin inhibits epithelial mesenchymal transition in renal tubular epithelial cells through PI3K/AKT and NF-κB pathways for treating renal fibrosis

Renal fibrosis is a crucial factor in the progression of chronic kidney diseases. Previous studies have suggested that apigenin (API) has potential in ameliorating renal fibrosis, but its therapeutic mechanism remains unclear. This study aims to elucidate the mechanisms by which API treats renal fibrosis using network pharmacology and experimental validation. Initially, we used the Traditional Chinese Medicine Systems Pharmacology (TCMSP) Database and GeneCards database to identify molecular targets of API and associated genes. Next, we constructed a network of API-renal fibrosis targets, followed by protein-protein interaction (PPI) analysis. Subsequent analyses, such as Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, were performed using the Database for Annotation, Visualization, and Integrated Discovery (DAVID). We also performed molecular docking studies to explore API's interactions with key proteins. To validate API's mechanism in treating renal fibrosis, we used a Human Kidney-2 (HK-2) cell model of epithelial-mesenchymal transition (EMT) induced by transforming growth factor-β1 (TGF-β1). We identified 77 API target genes, 8434 renal fibrosis target genes, and 64 intersection genes, which were primarily enriched in nuclear factor kappa-B (NF-κB) and Phosphatidylinositide 3-kinases/protein kinase B (PI3K-AKT) pathways. API significantly inhibited EMT in TGF-β1-induced HK-2 cells by regulating the expression of α-Smooth muscle actin (α-SMA) and E-cadherin and suppressing the protein expression of p-PI3K, p-AKT, and p-P65, which are related to the PI3K-AKT and NF-κB pathways. However, co-administration of the PI3K agonist 740Y-P counteracted API's inhibitory effects on these protein expressions. In summary, these findings highlight API's therapeutic potential in treating renal fibrosis by modulating EMT in renal tubular epithelial cells via the PI3K-AKT and NF-κB pathways.

Exploring macrophage heterogeneity in IgA nephropathy: Mechanisms of renal impairment and current therapeutic targets

The lack of understanding of the mechanism of renal injury in IgA nephropathy (IgAN) hinders the development of personalized treatment plans and targeted therapies. Improved insight into the cause of renal dysfunction in IgAN is necessary to enhance the effectiveness of strategies for slowing the progression of the disease. This study examined single cell RNA sequencing (scRNA seq) and bulk-RNA seq data and found that the gene expression of renal intrinsic cells (RIC) was significantly changed in patients with renal impairment, with a primary focus on energy metabolism. We discovered a clear metabolic reprogramming of RIC during renal function impairment (RF) using the 'scMetabolism' package, which manifested as a weakening of oxidative phosphorylation, alterations in fatty acid metabolism, and changes in glycolysis. Cellular communication analysis revealed that communication between macrophages (Ma) and RIC became more active and impacted cell function through the ligand-receptor-transcription factor (L-R-TF) axis in patients with RF. Our studies showed a notable upsurge in the expression of gene CLU and the infiltration of CLU+ Ma in patients with RF. CLU is a multifunctional protein, extensively involved in processes such as cell apoptosis and immune responses. Data obtained from the Nephroseq V5 database and multiplex immunohistochemistry (mIHC) were used to validate the findings, which were found to be robustly correlated with estimated glomerular filtration rate (eGFR) of the IgAN patients, as demonstrated by linear regression (LR). This study provides new insights into the cellular and molecular changes that occur in IgAN during renal impairment, revealing that elevated expression of CLU and CLU+ Ma percolation are common features in patients with RF. These findings offer potential targets and strategies for personalized management and targeted therapy of IgAN.

Allicin Ameliorated High-glucose Peritoneal Dialysis Solution-induced Peritoneal Fibrosis in Rats via the JAK2/STAT3 Signaling Pathway

Peritoneal fibrosis (PF) is one of the most serious complications of peritoneal dialysis (PD) and is the greatest obstacle to the clinical application of PD. Chinese herbal monomers have been effective in the prevention and treatment of PF. The aim of this study was to observe the effect of allicin on PF in rats induced by high glucose and to investigate its molecular mechanism of action. A rat model of PF was established by using a 4.25% glucose-based standard peritoneal dialysis solution. The degree of peritoneal pathological damage was assessed by Hematoxylin and eosin (H&E) staining. Peritoneal collagen deposition was detected by Masson's trichrome staining. The levels of Interleukin-6 (IL-6), Tumor necrosis factor-α (TNF-α), Interleukin-1β (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) in the serum were measured by Enzyme Linked Immunosorbent Assay (ELISA). The expression levels of TGF-β, α-smooth muscle actin (α-SMA) and collagen I were examined by western blotting and immunohistochemistry. The protein expression levels and mRNA levels of E-cadherin, N-cadherin, vimentin, janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) in peritoneal tissue were determined by western blotting and qRT-PCR. TGF-β1 stimulated human peritoneal mesothelial cells (HPMCs), and the cells were treated with allicin and the JAK2/STAT3 pathway activator colivelin alone or in combination. A cell counting kit-8 (CCK-8) assay was used to measure cell viability. The role of JAK2/STAT3 in the effects of allicin was confirmed via in vitro mechanistic research by western blotting, wound healing assays and Transwell assays. Allicin relieves the inflammatory response by downregulating the levels of IL-1β, IL-6, MCP-1 and TNF-α. Furthermore, allicin decreased the expression of TGF-β, α-SMA and collagen I. Allicin also alleviated epithelial-to-mesenchymal transition (EMT), as specifically manifested by increased E-cadherin and reduced N-cadherin and vimentin. Further studies revealed that allicin reduced the protein levels of JAK2, STAT3, p-JAK2, and p-STAT3. The results of the cellular experiments verified the above results. The ability of allicin to inhibit fibrosis and the EMT process was significantly attenuated after HPMCs were treated with colivelin. Taken together, these findings suggest that allicin inhibits inflammation and EMT, thereby improving PF, and this protective effect may be achieved by inhibiting the JAK2/STAT3 signaling pathway.

EGFR-ErbB2 dual kinase inhibitor lapatinib decreases autoantibody levels and worsens renal disease in Interferon α-accelerated murine lupus

Glomerulonephritis remains a major cause of morbidity and mortality in systemic lupus erythematosus (SLE). We have reported that expression of HER2/ErbB2, a member of the EGFR family, is increased in kidneys of patients and mice with lupus nephritis. We therefore asked if EGFR-family inhibition could ameliorate murine lupus nephritis. We used lapatinib, an EGFR-ErbB2 dual kinase inhibitor in female lupus-prone NZBxW/F1 mice, in which lupus onset was accelerated by injecting an IFN-α-expressing adenovirus. Mice received lapatinib (75 mg/Kg) or vehicle from the beginning of the acceleration or after the mice developed severe proteinuria (>300 mg/dL). Autoantibodies, kidney disease and markers of fibrosis and wound healing were analyzed. Exposure to IFNα induced ErbB2 expression in the kidney of lupus prone mice. Lapatinib, administered before but not after renal disease onset, lowered autoantibody titers and lessened immune complex deposition in the kidney. However, lapatinib increased proteinuria, kidney fibrosis and mouse mortality. Lapatinib also inhibited an in vitro wound healing assay testing renal cells. Our results suggest that EGFR-ErbB2 dual kinase inhibitor lapatinib decreases autoimmunity but worsens renal disease in IFNα-accelerated lupus, by increasing fibrosis and inhibiting wound healing. Type I Interferons are highlighted as important regulators of HER2/ErbB2 expression in the kidney. Further studies are required to parse the beneficial aspects of EGFR inhibition on autoimmunity from its negative effects on wound healing in lupus nephritis.

An In Situ Sustained-Release Chitosan Hydrogel to Attenuate Renal Fibrosis by Retaining Klotho Expression

Klotho (KLO) is an anti-fibrotic protein expressed in the kidneys and has been decreasing in the development of renal fibrosis (RF). However, restoring the decline in KLO levels remains a great challenge during RF treatment. Herein, an injectable KLO-loaded chitosan (CS) hydrogel (KLO-Gel) is designed to achieve localized and prolonged release of KLO in the RF treatment. KLO-Gel was prepared by cross-linking CS with β-glycerophosphate (β-GP), followed by rapid (within 3 min) thermosensitive gelation at 37 °C. Furthermore, KLO-Gel exhibited a slow and sustained release (over 14 d) of KLO both in PBS and in the kidneys of mice with unilateral ureter obstruction (UUO). A single local injection of KLO-Gel into the renal capsule of UUO mice was more effective at reducing RF (i.e., maintaining renal function and tissue structure, alleviating extracellular matrix accumulation, and inhibiting the TGF-β1/Smad2/3 signaling pathway) over a 14-d period than daily intraperitoneal injections of free KLO or captopril. Crucially, CS was found to induce endogenous KLO secretion, highlighting the added value of using CS in RF treatment. Overall, this study demonstrated that KLO-Gel enhanced the anti-fibrotic efficacy of KLO while minimizing its off-target toxicity, and its clinical potential awaits further validation.

The effects of cannabinoids on the kidney

Cannabinoids are a class of drugs derived from the Cannabis plant that are widely used for the treatment of various medical conditions and recreational use. Common examples include Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), spice, and 2-arachidonoylglycerol (2-AG). With more than 100 cannabinoids identified, their influence on the nervous system, role in pain management, and effects due to illicit use have been extensively studied. However, their effects on peripheral organs, such as the kidneys, require further examination. With dramatic rises in use, production, and legalization, it is essential to understand the impact and mechanistic properties of these drugs as they pertain to renal and cardiovascular physiology. The goal of this review is to summarize prior literature on the expression of cannabinoid receptors and how cannabinoids influence renal function. This review first discusses the interaction of the endocannabinoid system (ECS) and renal physiology and pathophysiology. Following, we briefly discuss the role of the ECS in various kidney diseases and the potential therapeutic applications of drugs targeting the cannabinoid system. Lastly, recent studies have identified several detrimental effects of cannabinoids, not only on the kidney but also in contributing to adverse cardiovascular outcomes. Thus, the negative impact of cannabinoids on renal function and the development of various cardiovascular diseases is also discussed.

Leishmania major surface components and DKK1 signalling via LRP6 promote migration and longevity of neutrophils in the infection site

Background

Host-related factors highly regulate the increased circulation of neutrophils during Leishmania infection. Platelet-derived Dickkopf-1 (DKK1) is established as a high-affinity ligand to LRP6. Recently, we demonstrated that DKK1 upregulates leukocyte-platelet aggregation, infiltration of neutrophils to the draining lymph node and Th2 differentiation during Leishmania infection, suggesting the potential involvement of the DKK1-LRP6 signalling pathway in neutrophil migration in infectious diseases.

Results

In this study, we further explored the potential role of DKK1-LRP6 signalling in the migration and longevity of activated neutrophils in the infection site using BALB/c mice with PMNs deficient in LRP6 (LRP6NKO) or BALB/c mice deficient in both PMN LRP6 and platelet DKK1 (LRP6NKO DKK1PKO). Relative to the infected wild-type BALB/c mice, reduced neutrophil activation at the infection site of LRP6NKO or LRP6NKO DKK1PKO mice was noted. The neutrophils obtained from either infected LRP6NKO or LRP6NKO DKK1PKO mice additionally showed a high level of apoptosis. Notably, the level of LRP6 expressing neutrophils was elevated in infected BALB/c mice. Relative to infected BALB/c mice, a significant reduction in parasite load was observed in both LRP6NKO and LRP6NKO DKK1PKO infected mice. Notably, DKK1 levels were comparable in the LRP6NKO and BALB/c mice in response to infection, indicating that PMN activation is the major pathway for DKK1 in promoting parasitemia. Parasite-specific components also play a crucial role in modulating neutrophil circulation in Leishmania disease. Thus, we further determine the contribution of Leishmania membrane components in the migration of neutrophils to the infection site using null mutants deficient in LPG synthesis (Δlpg1- ) or lacking all ether phospholipids (plasmalogens, LPG, and GIPLs) synthesis (Δads1- ). Relative to the WT controls, Δads1- parasite-infected mice showed a sustained decrease in neutrophils and neutrophil-platelet aggregates (for at least 14 days PI), while neutrophils returned to normal in Δlpg1- parasite-infected mice after day 3 PI.

Conclusion

Our results suggest that DKK1 signalling and Leishmania pathogen-associated molecular patterns appear to regulate the migration and sustenance of viable activated neutrophils in the infection site resulting in chronic type 2 cell-mediated inflammation.

β-catenin-inhibited Sumoylation modification of LKB1 and fatty acid metabolism is critical in renal fibrosis

Liver kinase B1 (LKB1) is a serine/threonine kinase controlling cell homeostasis. Among post-translational modification, Sumoylation is vital for LKB1 activating adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), the key regulator in energy metabolism. Of note, AMPK-regulated fatty acid metabolism is highly involved in maintaining normal renal function. However, the regulative mechanisms of LKB1 Sumoylation remain elusive. In this study, we demonstrated that β-catenin, a notorious signal in renal fibrosis, inhibited the Sumoylation of LKB1, thereby disrupting fatty acid oxidation in renal tubular cells and triggering renal fibrosis. Mechanically, we found that Sumo3 was the key mediator for LKB1 Sumoylation in renal tubular cells, which was transcriptionally inhibited by β-catenin/Transcription factor 4 (TCF4) signaling. Overexpression of Sumo3, not Sumo1 or Sumo2, restored β-catenin-disrupted fatty acid metabolism, and retarded lipid accumulation and fibrogenesis in the kidney. In vivo, conditional knockout of β-catenin in tubular cells effectively preserved fatty acid oxidation and blocked lipid accumulation by maintaining LKB1 Sumoylation and AMPK activation. Furthermore, ectopic expression of Sumo3 strongly inhibited Wnt1-aggravated lipid accumulation and fibrogenesis in unilateral ischemia-reperfusion mice. In patients with chronic kidney disease, we found a loss of Sumo3 expression, and it was highly related to LKB1 repression. This contributes to fatty acid metabolism disruption and lipid accumulation, resulting in renal fibrosis. Overall, our study revealed a new mechanism in fatty acid metabolism dysfunction and provided a new therapeutic target pathway for regulating Sumo modification in renal fibrosis.

Single-cell resolution of intestinal regeneration in pythons without crypts illuminates conserved vertebrate regenerative mechanisms

Canonical models of intestinal regeneration emphasize the critical role of the crypt stem cell niche to generate enterocytes that migrate to villus ends. Burmese pythons possess extreme intestinal regenerative capacity yet lack crypts, thus providing opportunities to identify noncanonical but potentially conserved mechanisms that expand our understanding of regenerative capacity in vertebrates, including humans. Here, we leverage single-nucleus RNA sequencing of fasted and postprandial python small intestine to identify the signaling pathways and cell-cell interactions underlying the python's regenerative response. We find that python intestinal regeneration entails the activation of multiple conserved mechanisms of growth and stress response, including core lipid metabolism pathways and the unfolded protein response in intestinal enterocytes. Our single-cell resolution highlights extensive heterogeneity in mesenchymal cell population signaling and intercellular communication that directs major tissue restructuring and the shift out of a dormant fasted state by activating both embryonic developmental and wound healing pathways. We also identify distinct roles of BEST4+ enterocytes in coordinating key regenerative transitions via NOTCH signaling. Python intestinal regeneration shares key signaling features and molecules with mammalian gastric bypass, indicating that conserved regenerative programs are common to both. Our findings provide different insights into cooperative and conserved regenerative programs and intercellular interactions in vertebrates independent of crypts which have been otherwise obscured in model species where temporal phases of generative growth are limited to embryonic development or recovery from injury.

Distinct role of Klotho in long bone and craniofacial bone: skeletal development, repair and regeneration

Bone defects are highly prevalent diseases caused by trauma, tumors, inflammation, congenital malformations and endocrine abnormalities. Ideally effective and side effect free approach to dealing with bone defects remains a clinical conundrum. Klotho is an important protein, which plays an essential role in regulating aging and mineral ion homeostasis. More recently, research revealed the function of Klotho in regulating skeleton development and regeneration. Klotho has been identified in mesenchymal stem cells, osteoblasts, osteocytes and osteoclasts in different skeleton regions. The specific function and regulatory mechanisms of Klotho in long bone and craniofacial bone vary due to their different embryonic development, ossification and cell types, which remain unclear and without conclusion. Moreover, studies have confirmed that Klotho is a multifunctional protein that can inhibit inflammation, resist cancer and regulate the endocrine system, which may further accentuate the potential of Klotho to be the ideal molecule in inducing bone restoration clinically. Besides, as an endogenous protein, Klotho has a promising potential for clinical therapy without side effects. In the current review, we summarized the specific function of Klotho in long bone and craniofacial skeleton from phenotype to cellular alternation and signaling pathway. Moreover, we illustrated the possible future clinical application for Klotho. Further research on Klotho might help to solve the existing clinical difficulties in bone healing and increase the life quality of patients with bone injury and the elderly.

Integrin alpha1 beta1 promotes interstitial fibrosis in a mouse model of polycystic kidney disease

Fibrosis is the cause of end-stage kidney failure in patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD). The molecular and cellular mechanisms involved in fibrosis are complex and anti-fibrotic therapies have so far failed to make an impact on patient welfare. Using unbiased proteomics analysis on the Pkd1 nl/nl mouse, we found that expression of the integrin α1 subunit is increased in this model of ADPKD. In human ADPKD tissue and two single cell RNA kidney disease datasets, ITGA1 was also upregulated. To investigate the functional role of this integrin subunit in ADPKD, we generated a Pkd1 nl/nl Itga1 -/- mouse. We observed a significant reduction in kidney volume and kidney dysfunction in mice lacking the integrin α1 subunit. Kidneys from Pkd1 nl/nl Itga1 -/- mice had smaller cysts and reduced interstitial expansion and tubular atrophy. Picrosirius red staining identified a restriction in collagen staining in the interstitium and the myofibroblast marker α smooth muscle actin was also downregulated. Myofibroblast cell proliferation was reduced in Pkd1 nl/nl Itga1 -/- mice and primary fibroblast cultures demonstrated an abrogated fibrogenic phenotype in integrin α1-depleted fibroblasts. These results highlight a previously unrecognised role for the integrin α1 subunit in kidney fibrosis.

Andrographolide: A promising therapeutic agent against organ fibrosis

Fibrosis is the terminal pathology of chronic illness in many organs, marked by excessive accumulation of extracellular matrix proteins. These changes influence organ function, ultimately resulting in organ failure. Although significant progress has been achieved in comprehending the molecular pathways responsible for fibrosis in the last decades, effective and approved clinical therapies for the condition are still lacking. Andrographolide is a diterpenoid isolated and purified mainly from the aboveground parts of the Andrographis paniculata plant, which possesses good effects of purging heat, detoxifying, antibacterial and anti-inflammatory. In-depth research has gradually confirmed the anticancer, antioxidant, antiviral and other effects of Andro so that it can play a preventive and therapeutic role in various diseases. Over the past few years, an increasing number of research findings have indicated that Andro exerts antifibrotic effects in various organs by acting on transforming growth factor-β/small mother against decapentaplegic protein, mitogen-activated protein kinases, nuclear factor-E2-related factor 2, nuclear factor kappa-B and other signalling molecules to inhibit inflammation, oxidative stress, epithelial-mesenchymal transition, fibroblast activation and collagen buildup. This review presents a compilation of findings regarding the antifibrotic impact of Andro in tissue and cell models in vitro and in vivo. Emphasis is placed on the potential therapeutic benefits of Andro in diseases related to organ fibrosis. Existing studies and cutting-edge technologies on Andro pharmacokinetics, toxicity and bioavailability are briefly discussed to provide evidence for accelerating its clinical conversion and adoption.

Harnessing the role of aberrant cell signaling pathways in glioblastoma multiforme: a prospect towards the targeted therapy

Glioblastoma Multiforme (GBM), designated as grade IV by the World Health Organization, is the most aggressive and challenging brain tumor within the central nervous system. Around 80% of GBM patients have a poor prognosis, with a median survival of 12-15 months. Approximately 90% of GBM cases originate from normal glial cells via oncogenic processes, while the remainder arise from low-grade tumors. GBM is notorious for its heterogeneity, high recurrence rates, invasiveness, and aggressive behavior. Its malignancy is driven by increased invasive migration, proliferation, angiogenesis, and reduced apoptosis. Throughout various stages of central nervous system (CNS) development, pivotal signaling pathways, including Wnt/β-catenin, Sonic hedgehog signaling (Shh), PI3K/AKT/mTOR, Ras/Raf/MAPK/ERK, STAT3, NF-КB, TGF-β, and Notch signaling, orchestrate the growth, proliferation, differentiation, and migration of neural progenitor cells in the brain. Numerous upstream and downstream regulators within these signaling pathways have been identified as significant contributors to the development of human malignancies. Disruptions or aberrant activations in these pathways are linked to gliomagenesis, enhancing the invasiveness, progression, and aggressiveness of GBM, along with epithelial to mesenchymal transition (EMT) and the presence of glioma stem cells (GSCs). Traditional GBM treatment involves surgery, radiotherapy, and chemotherapy with Temozolomide (TMZ). However, most patients experience tumor recurrence, leading to low survival rates. This review provides an overview of the major cell signaling pathways involved in gliomagenesis. Furthermore, we explore the signaling pathways leading to therapy resistance and target key molecules within these signaling pathways, paving the way for the development of novel therapeutic approaches.

Dual blockade of endothelin A and angiotensin II type 1 receptors with sparsentan as a novel treatment strategy to alleviate IgA nephropathy

INTRODUCTION

Although immunoglobulin A nephropathy (IgAN) had been discovered more than 50 years ago, 30-40% of IgAN patients still have primary glomerular disease that progresses to end-stage renal disease. However, various treatment strategies for IgAN have rapidly expanded in recent years to include endothelin (ET) receptor antagonists.

AREAS COVERED

In this review, we discuss the role of the ET-1/ETA receptor axis in the development of IgAN, especially focusing on the potential of sparsentan, a dual ET and angiotensin receptor antagonist as a novel therapy for IgAN.

EXPERT OPINION

Evaluation of the MEST-C score at the time of renal biopsy in IgAN is important in determining treatment strategies. If lesions are mainly in the acute phase, such as crescents, steroid therapy should be continued. However, if lesions are mainly in the chronic phase, such as glomerulosclerosis, sparsentan rather than steroid or angiotensin II receptor blocker alone may improve renal outcomes. Although further clinical studies are needed to back up these assumptions, appropriate combination of new drugs containing sparsentan and conventional drugs for IgAN treatment at the appropriate disease stage is expected to further inhibit the progression of renal damage.

The adipose tissue keeps the score: priming of the adrenal-adipose tissue axis by early life stress predisposes women to obesity and cardiometabolic risk

Adverse Childhood Experiences (ACEs) refer to early life stress events, including abuse, neglect, and other psychosocial childhood traumas that can have long-lasting effects on a wide range of physiological functions. ACEs provoke sex-specific effects, whereas women have been shown to display a strong positive correlation with obesity and cardiometabolic disease. Notably, rodent models of chronic behavioral stress during postnatal life recapitulate several effects of ACEs in a sex-specific fashion. In this review, we will discuss the potential mechanisms uncovered by models of early life stress that may explain the greater susceptibility of females to obesity and metabolic risk compared with their male counterparts. We highlight the early life stress-induced neuroendocrine shaping of the adrenal-adipose tissue axis as a primary event conferring sex-dependent heightened sensitivity to obesity.

HO-1: An emerging target in fibrosis

Fibrosis, an aberrant reparative response to tissue injury, involves a disruption in the equilibrium between the synthesis and degradation of the extracellular matrix, leading to its excessive accumulation within normal tissues, and culminating in organ dysfunction. Manifesting in the terminal stages of nearly all chronic ailments, fibrosis carries a high mortality rate and poses a significant threat to human health. Heme oxygenase-1 (HO-1) emerges as an endogenous protective agent, mitigating tissue damage through its antioxidant, anti-inflammatory, and antiapoptotic properties. Numerous studies have corroborated HO-1's potential as a therapeutic target in anti-fibrosis treatment. This review delves into the structural and functional attributes, and the upstream and downstream pathways of HO-1. Additionally, the regulatory networks and mechanisms of HO-1 in cells associated with fibrosis are elucidated. The role of HO-1 in various fibrosis-related diseases is also explored. Collectively, this comprehensive information serves as a foundation for future research and augments the viability of HO-1 as a therapeutic target for fibrosis.

Inhibition of matrix metalloproteinases to reduce blood brain barrier disruption and haemorrhagic transformation in ischaemic stroke: Go broad or go narrow?

Ischaemic stroke characterises impulsive cerebral-region hypoxia due to deep intracerebral arteriole blockage, often accompanied by permanent cerebral infarction and cognitive impairment. Thrombolysis with recombinant tissue plasminogen activator (rtPA) and thrombectomy remain the only guidance-approved therapies. However, emerging data draws clear links between such therapies and haemorrhage transformation, which occur when cerebral vasculature is damaged during ischaemia/reperfusion. Studies have shown that matrix metalloproteinases (MMPs) play a significant role in haemorrhage transformation, by depleting the extracellular matrix (ECM) and disrupting the blood brain barrier (BBB). Inhibitors of MMPs may be used to prevent ischaemic stroke patients from BBB disruption and haemorrhage transformation, particularly for those receiving rtPA treatment. Preclinical studies found that inhibition of MMPs with agents or in knock out mice, effectively reduced BBB disruption and infarct volume, leading to improved ischaemic stroke outcomes. At present, MMP inhibition is not an approved therapy for stroke patients. There remain concerns about timing, dosing, duration of MMP inhibition and selection of either broad spectrum or specific MMP inhibitors for stroke patients. This review aims to summarize current knowledge on MMP inhibition in ischaemic stroke and explore whether a broad spectrum or a specific MMP inhibitor should be used for ischaemic stroke patient treatment. It is crucial to inhibit MMP activities early and sufficiently to ensure BBB intact during ischaemia and reperfusion, but also to reduce side effects of MMP inhibitors to minimum. Recent advance in stroke therapy by thrombectomy could aid in such treatment with intra-arterially delivery of MMP inhibitors (and/or antioxidants).

Right ventricular remodeling induced by prolonged excessive endurance exercise is mediated by upregulating Wnt/β-catenin signaling in rats

BACKGROUND

The aim of this study was to develop an animal model to investigate whether prolonged intensive endurance exercise induces RV remodeling, taking into account the involvement of Wnt/β-catenin signaling.

METHODS

Four-week-old male Wistar rats (100 to 125 g) were assigned to four groups (n = 8/group): 1) sixteen weeks of intensive (36 m/min) exercise (INT), 2) twelve weeks of the intensive exercise followed by four weeks of moderate intensity (18 m/min) exercise (INT + MOD), 3) twelve weeks of the intensive exercise followed by four weeks of detraining (INT + DT), and 4) sedentary rats (SED). The exercise protocols were performed five days a week for one h/day. Echocardiography, real-time PCR, western blotting, and histological staining were performed at the end of week sixteen.

RESULTS

INT rats developed concentric hypertrophy without diastolic dysfunction compared to SED (p = 0.006) and INT + DT (p = 0.035). Wnt1, β-catenin and CyclinD1 proteins in the training groups were significantly higher than SED rats (p < 0.001). Interestingly, INT rats had higher protein levels than INT + DT and INT + MOD (p < 0.001), with higher gene expression compared to SED rats (p < 0.05). There was also a significant increase in collagen deposition in INT rats compared to SED (p = 0.046) and INT + DT (p = 0.034). Furthermore, INT + MOD and INT + DT rats did not show any adverse structural, functional, or histological changes.

CONCLUSIONS

Long-term intensive endurance training seems to be associated with increased collagen deposition and wall thickness in the RV through Wnt/β-catenin signaling (which is concentration dependent), without changes in diastolic function.

CLINICAL PERSPECTIVE

Over the past decades, there has been an ongoing debate about whether the structural and functional adaptations of the cardiovascular system in trained endurance athletes are benign physiological responses to training or potentially pathological changes related to disease. While the adaptations of the left heart are well-documented, the remodeling of the right heart remains a subject of discussion. To gain insights into the ability of sustained high-intensity exercise to cause adverse right ventricular (RV) remodeling, we conducted an experimental study in which male rats were trained to run vigorously for 1 h daily over a 16-week period and compared them to a parallel group of sedentary control rats. Our findings revealed that intense long-term exercise induced morphological changes along with fibrosis affecting the RV. These fibrotic changes were a result of the 16-week vigorous exercise training regimen. If these results are confirmed in humans, they suggest that prolonged high-intensity endurance exercise training may lead to adverse cardiac remodeling. Our findings have important potential implications for the assessment of cardiac remodeling in individuals engaged in high-level exercise training.

β-Mangostin Alleviates Renal Tubulointerstitial Fibrosis via the TGF-β1/JNK Signaling Pathway

The epithelial-to-mesenchymal transition (EMT) plays a key role in the pathogenesis of kidney fibrosis, and kidney fibrosis is associated with an adverse renal prognosis. Beta-mangostin (β-Mag) is a xanthone derivative obtained from mangosteens that is involved in the generation of antifibrotic and anti-oxidation effects. The purpose of this study was to examine the effects of β-Mag on renal tubulointerstitial fibrosis both in vivo and in vitro and the corresponding mechanisms involved. As shown through an in vivo study conducted on a unilateral ureteral obstruction mouse model, oral β-Mag administration, in a dose-dependent manner, caused a lesser degree of tubulointerstitial damage, diminished collagen I fiber deposition, and the depressed expression of fibrotic markers (collagen I, α-SMA) and EMT markers (N-cadherin, Vimentin, Snail, and Slug) in the UUO kidney tissues. The in vitro part of this research revealed that β-Mag, when co-treated with transforming growth factor-β1 (TGF-β1), decreased cell motility and downregulated the EMT (in relation to Vimentin, Snail, and N-cadherin) and phosphoryl-JNK1/2/Smad2/Smad3 expression. Furthermore, β-Mag co-treated with SB (Smad2/3 kinase inhibitor) or SP600125 (JNK kinase inhibitor) significantly inhibited the TGF-β1-associated downstream phosphorylation and activation of JNK1/2-mediated Smad2 targeting the Snail/Vimentin axis. To conclude, β-Mag protects against EMT and kidney fibrotic processes by mediating the TGF-β1/JNK/Smad2 targeting Snail-mediated Vimentin expression and may have therapeutic implications for renal tubulointerstitial fibrosis.

Yiqihuoxue decoction (GSC) inhibits mitochondrial fission through the AMPK pathway to ameliorate EPCs senescence and optimize vascular aging transplantation regimens

BACKGROUND

During the aging process, the number and functional activity of endothelial progenitor cells (EPCs) are impaired, leading to the unsatisfactory efficacy of transplantation. Previous studies demonstrated that Yiqihuoxue decoction (Ginseng-Sanqi-Chuanxiong, GSC) exerts anti-vascular aging effects. The purpose of this study is to evaluated the effects of GSC on D-galactose (D-gal)induced senescence and the underlying mechanisms.

METHODS

The levels of cellular senescence-related markers P16, P21, P53, AMPK and p-AMPK were detected by Western blot analysis (WB). SA-β-gal staining was used to evaluate cell senescence. EPCs function was measured by CCK-8, Transwell cell migration and cell adhesion assay. The morphological changes of mitochondria were detected by confocal microscopy. The protein and mRNA expression of mitochondrial fusion fission Drp1, Mff, Fis1, Mfn1, Mfn2 and Opa1 in mitochondria were detect using WB and RT-qPCR. Mitochondrial membrane potential, mtROS and ATP of EPCs were measured using IF. H&E staining was used to observe the pathological changes and IMT of the aorta. The expressions of AGEs, MMP-2 and VEGF in aorta were measured using Immunohistochemical (IHC). The levels of SOD, MDA, NO and ET-1 in serum were detected by SOD, MDA and NO kits.

RESULTS

In vitro, GSC ameliorated the senescence of EPCs induced by D-gal and reduced the expression of P16, P21 and P53. The mitochondrial morphology of EPCs was restored, the expression of mitochondrial Drp1, Mff and Fis1 protein was decreased, the levels of mtROS and ATP were decreased, and mitochondrial function was improved. Meanwhile, the expression of AMPK and p-AMPK increased. The improvement effects of GSC on aging and mitochondrial morphology and function were were hindered after adding AMPK inhibitor. In vivo, GSC improved EPCs efficiency, ameliorated aortic structural disorder and decreased IMT in aging mice. The serum SOD level increased and MDA level decreased, indicating the improvement of antioxidant capacity. Increased NO content and ET-1 content suggested improvement of vascular endothelial function. The changes observed in SOD and MMP-2 suggested a reduction in vascular stiffness and the degree of vascular damage. The decreased expression of P21 and P53 indicates the delay of vascular senescence.

Effects of cadherin mediated contact normalization on oncogenic Src kinase mediated gene expression and protein phosphorylation

Nontransformed cells form heterotypic cadherin junctions with adjacent transformed cells to inhibit tumor cell growth and motility. Transformed cells must override this form of growth control, called "contact normalization", to invade and metastasize during cancer progression. Heterocellular cadherin junctions between transformed and nontransformed cells are needed for this process. However, specific mechanisms downstream of cadherin signaling have not been clearly elucidated. Here, we utilized a β-catenin reporter construct to determine if contact normalization affects Wnt signaling in transformed cells. β-catenin driven GFP expression in Src transformed mouse embryonic cells was decreased when cultured with cadherin competent nontransformed cells compared to transformed cells cultured with themselves, but not when cultured with cadherin deficient nontransformed cells. We also utilized a layered culture system to investigate the effects of oncogenic transformation and contact normalization on gene expression and oncogenic Src kinase mediated phosphorylation events. RNA-Seq analysis found that cadherin dependent contact normalization inhibited the expression of 22 transcripts that were induced by Src transformation, and increased the expression of 78 transcripts that were suppressed by Src transformation. Phosphoproteomic analysis of cells expressing a temperature sensitive Src kinase construct found that contact normalization decreased phosphorylation of 10 proteins on tyrosine residues that were phosphorylated within 1 h of Src kinase activation in transformed cells. Taken together, these results indicate that cadherin dependent contact normalization inhibits Wnt signaling to regulate oncogenic kinase activity and gene expression, particularly PDPN expression, in transformed cells in order to control tumor progression.

Urine Extracellular Vesicles Size Subsets as Lupus Nephritis Biomarkers

Systemic lupus erythematosus (SLE) is an autoimmune disorder that often leads to kidney injury, known as lupus nephritis (LN). Although renal biopsy is the primary way to diagnose LN, it is invasive and not practical for regular monitoring. As an alternative, several groups have proposed urinary extracellular vesicles (uEVs) as potential biomarkers for LN, as recent studies have shown their significance in reflecting kidney-related diseases. As a result, we developed a flow cytometry approach that allowed us to determine that LN patients exhibited a significantly higher total uEV concentration compared to SLE patients without kidney involvement. Additionally, an analysis of different-sized uEV subsets revealed that microvesicles ranging from 0.3 to 0.5 μm showed the most promise for distinguishing LN. These findings indicate that evaluating uEV concentration and size distribution could be a valuable diagnostic and monitoring tool for LN, pending further validation in more comprehensive studies.

Representation of multimorbidity and frailty in the development and validation of kidney failure prognostic prediction models: a systematic review

BACKGROUND

Prognostic models that identify individuals with chronic kidney disease (CKD) at greatest risk of developing kidney failure help clinicians to make decisions and deliver precision medicine. It is recognised that people with CKD usually have multiple long-term health conditions (multimorbidity) and often experience frailty. We undertook a systematic review to evaluate the representation and consideration of multimorbidity and frailty within CKD cohorts used to develop and/or validate prognostic models assessing the risk of kidney failure.

METHODS

We identified studies that described derivation, validation or update of kidney failure prognostic models in MEDLINE, CINAHL Plus and the Cochrane Library-CENTRAL. The primary outcome was representation of multimorbidity or frailty. The secondary outcome was predictive accuracy of identified models in relation to presence of multimorbidity or frailty.

RESULTS

Ninety-seven studies reporting 121 different kidney failure prognostic models were identified. Two studies reported prevalence of multimorbidity and a single study reported prevalence of frailty. The rates of specific comorbidities were reported in a greater proportion of studies: 67.0% reported baseline data on diabetes, 54.6% reported hypertension and 39.2% reported cardiovascular disease. No studies included frailty in model development, and only one study considered multimorbidity as a predictor variable. No studies assessed model performance in populations in relation to multimorbidity. A single study assessed associations between frailty and the risks of kidney failure and death.

CONCLUSIONS

There is a paucity of kidney failure risk prediction models that consider the impact of multimorbidity and/or frailty, resulting in a lack of clear evidence-based practice for multimorbid or frail individuals. These knowledge gaps should be explored to help clinicians know whether these models can be used for CKD patients who experience multimorbidity and/or frailty.

SYSTEMATIC REVIEW REGISTRATION

This review has been registered on PROSPERO (CRD42022347295).

Advances in the mechanisms of vascular calcification in chronic kidney disease

Vascular calcification (VC) is common in patients with advanced chronic kidney disease (CKD).A series of factors, such as calcium and phosphorus metabolism disorders, uremic toxin accumulation, inflammation and oxidative stress and cellular senescence, cause osteoblast-like differentiation of vascular smooth muscle cells, secretion of extracellular vesicles, and imbalance of calcium regulatory factors, which together promote the development of VC in CKD. Recent advances in epigenetics have provided better tools for the investigation of VC etiology and new approaches for finding more accurate biomarkers. These advances have not only deepened our understanding of the pathophysiological mechanisms of VC in CKD, but also provided valuable clues for the optimization of clinical predictors and the exploration of potential therapeutic targets. The aim of this article is to provide a comprehensive overview of the pathogenesis of CKD VC, especially the new advances made in recent years, including the various key factors mentioned above. Through the comprehensive analysis, we expect to provide a solid theoretical foundation and research direction for future studies targeting the specific mechanisms of CKD VC, the establishment of clinical predictive indicators and the development of potential therapeutic strategies.

The LncRNA6524/miR-92a-2-5p/Dvl1/Wnt/β-catenin axis promotes renal fibrosis in the UUO mouse model

LncRNAs are reported to participate in multiple biological and pathological processes, including renal fibrosis due to obstructive nephropathy. However, the function and mechanisms of each lncRNA in this context differ. In this study, we created a fibrosis model in vitro using TGF-β1 treatment and in vivo through unilateral ureteral obstruction. We demonstrated that lncRNA6524 expression increased in both models, as confirmed by qPCR. Additionally, we discovered that lncRNA6524 mediates the TGF-β1-induced accumulation of extracellular matrix (ECM) proteins in BUMPT cells. We investigated the mechanism using dual luciferase reporter assays, immunofluorescence, and qPCR. Our results indicate that lncRNA6524 acts as a sponge for miR-92a-2-5p, promoting renal fibrosis by upregulating the Dvl1/Wnt/β-catenin signaling pathway. In summary, our findings demonstrate a linear regulatory relationship among lncRNA6524, miR-92a-2-5p, and the Dvl1/Wnt/β-catenin axis in renal epithelial cells during kidney obstruction. This highlights a new potential target for treating obstruction-related renal fibrosis.

Lack of Cannabinoid Type 2 Promoter Activity in Normal or Injured Kidneys Using a Cnr2-GFP Reporter Mouse

Introduction: Although cannabinoid type 2 (CB2) receptor activity is known to promote diverse biological functions in the kidney, published data regarding CB2 receptor protein levels and cellular distribution within the kidney is inconsistent. The goal of the present study was to investigate the changes of CB2 in the kidney obtained from mice exposed to various forms of kidney injury using a genetic mouse model expressing green fluorescent protein (GFP) driven by the endogenous cannabinoid receptor 2 (Cnr2) promoter. Materials and Methods: Kidney injury was established in a genetic mouse model expressing green fluorescent protein (GFP) driven by the endogenous Cnr2 promoter. Kidney injury was initiated by either treatment with different chemicals [cisplatin or lipopolysaccharide (LPS)] or by unilateral ureteral obstruction (UUO). Changes in the detection of GFP were used as a proxy for CB2 levels and localization. Histological changes due to the injury stimuli were observed by time-related, morphological changes in kidney cytoarchitecture and blood parameters, such as serum creatinine levels. Cnr2 mRNA levels were detected by reverse transcription coupled to polymerase chain reaction (RT-PCR) while protein changes in the tissue lysates were measured by Western blot analysis. Cellular localization of GFP was detected by fluorescent microscopy. Results: Our data demonstrated that there was no band or a minimally detectable band for GFP using kidney lysates from vehicle- or cisplatin-treated mice. A similar lack of GFP was detected in the UUO kidney versus the contralateral control kidney. This is consistent with the low, albeit detectable levels of Cnr2 mRNA in the kidney samples from control or cisplatin treatment. In frozen kidney sections from vehicle and cisplatin-treated mice, GFP fluorescence was not detectable in tubular epithelia, glomeruli or blood vessels in the cortex. Instead, GFP was detected in rare cells within the interstitial space. A second chemical injury model using LPS found a similar lack of GFP protein levels and an absence of legitimate GFP fluorescence in the main cell types within the kidney. Conclusion: These findings suggest that Cnr2 promoter activity is minimally active in normal or injured kidneys, and that pharmacological manipulation of CB2 receptors may be associated with receptors being expressed in cells recruited to the kidney.

The contribution of the sphingosine 1-phosphate signaling pathway to chronic kidney diseases: recent findings and new perspectives

Chronic kidney disease (CKD) is a multifactorial condition with diverse etiologies, such as diabetes mellitus, hypertension, and genetic disorders, often culminating in end-stage renal disease (ESRD). A hallmark of CKD progression is kidney fibrosis, characterized by the excessive accumulation of extracellular matrix components, for which there is currently no effective anti-fibrotic therapy. Recent literature highlights the critical role of sphingosine 1-phosphate (S1P) signaling in CKD pathogenesis and renal fibrosis. This review provides an in-depth analysis of the latest findings on S1P metabolism and signaling in renal fibrosis and in specific CKDs, including diabetic nephropathy (DN), lupus nephritis (LN), focal segmental glomerulosclerosis (FSGS), Fabry disease (FD), and IgA nephropathy (IgAN). Emerging studies underscore the therapeutic potential of modulating S1P signaling with receptor modulators and inhibitors, such as fingolimod (FTY720) and more selective agents like ozanimod and cenerimod. Additionally, the current knowledge about the effects of established kidney protective therapies such as glucocorticoids and SGLT2 and ACE inhibitors on S1P signaling will be summarized. Furthermore, the review highlights the potential role of S1P as a biomarker for disease progression in CKD models, particularly in Fabry disease and diabetic nephropathy. Advanced technologies, including spatial transcriptomics, are further refining our understanding of S1P's role within specific kidney compartments. Collectively, these insights emphasize the need for continued research into S1P signaling pathways as promising targets for CKD treatment strategies.

Dense Collagen I as a Biomimetic Material to Track Matrix Remodelling in Renal Carcinomas

Aims: Renal tissue is a dynamic biophysical microenvironment, regulating healthy function and influencing tumor development. Matrix remodelling is an iterative process and aberrant tissue repair is prominent in kidney fibrosis and cancer. Biomimetic 3D models recapitulating the collagen composition and mechanical fidelity of native renal tissue were developed to investigate cell-matrix interactions in renal carcinomas. Methods: Collagen I and laminin hydrogels were engineered with renal cancer cells (ACHN and 786-O), which underwent plastic compression to generate dense matrices. Mechanical properties were determined using shear rheology and qPCR determined the gene expression of matrix markers. Results: The shear modulus and phase angle of acellular dense collagen I gels (474 Pa and 10.7) are similar to human kidney samples (1410 Pa and 10.5). After 21 days, 786-O cells softened the dense matrix (∼155 Pa), with collagen IV downregulation and upregulation of matrix metalloproteinases (MMP7 and MMP8). ACHN cells were found to be less invasive and stiffened the matrix to ∼1.25 kPa, with gene upregulation of collagen IV and the cross-linking enzyme LOX. Conclusions: Renal cancer cells remodel their biophysical environment, altering the material properties of tissue stroma in 3D models. These models can generate physiologically relevant stiffness to investigate the different matrix remodelling mechanisms utilized by cancer cells.

Soluble Epoxide Hydrolase Inhibition Attenuates Proteinuria by Alleviating Renal Inflammation and Podocyte Injuries in Adriamycin-Induced Nephropathy

Soluble epoxide hydrolase (sEH) has previously been demonstrated to play an important part in kidney diseases by hydrolyzing renoprotective epoxyeicosatrienoic acids to their less active diols. However, little is known about the role of sEH in primary glomerular diseases. Here, we investigated the effects of sEH inhibition on proteinuria in primary glomerular diseases and the underlying mechanism. The expression of sEH in the renal tubules of patients with minimal change disease, IgA nephropathy, and membranous nephropathy was significantly increased. Renal sEH expression level was positively correlated with the 24 h urine protein excretion and negatively correlated with serum albumin. In the animal model of Adriamycin (ADR)-induced nephropathy, renal sEH mRNA and protein expression increased significantly. Pharmacological inhibition of sEH with AUDA effectively reduced urine protein excretion and attenuated renal pathological damage. Furthermore, sEH inhibition markedly abrogated the abnormal expressions of nephrin and desmin in glomerular podocytes induced by ADR. More importantly, AUDA treatment inhibited renal NF-κB activation and reduced TNF-α levels in rats with ADR-induced nephropathy. Overall, our findings suggest that sEH inhibition ameliorates renal inflammation and podocyte injury, thus reducing proteinuria and exerting renoprotective effects. Targeting sEH might be a potential strategy for the treatment of proteinuria in primary glomerular diseases.

Spatiotemporal delivery of multiple components of rhubarb-astragalus formula for the sysnergistic treatment of renal fibrosis

Purpose

Rhubarb (Rheum palmatum L.) and astragalus (Radix astragali) find widespread used in clinical formulations for treating chronic kidney disease (CKD). Notably, the key active components, total rhubarb anthraquinone (TRA) and total astragalus saponin (TAS), exhibit superiority over rhubarb and astragalus in terms of their clear composition, stability, quality control, small dosage, and efficacy for disease treatment. Additionally, astragalus polysaccharides (APS) significantly contribute to the treatment of renal fibrosis by modulating the gut microbiota. However, due to differences in the biopharmaceutical properties of these components, achieving synergistic effects remains challenging. This study aims to develop combined pellets (CPs) and evaluate the potential effect on unilateral ureteral obstruction (UUO)-induced renal fibrosis.

Methods

The CPs pellets were obtained by combining TRA/TAS-loaded SNEDDS pellets and APS-loaded pellets, prepared using the fluidized bed coating process. The prepared pellets underwent evaluation for morphology, bulk density, hardness, and flowing property. Moreover, the in vitro release of the payloads was evaluated with the CHP Type I method. Furthermore, the unilateral ureteral obstruction (UUO) model was utilized to investigate the potential effects of CPs pellets on renal fibrosis and their contribution to gut microbiota modulation.

Results

The ex-vivo study demonstrated that the developed CPs pellets not only improved the dissolution of TRA and TAS but also delivered TRA/TAS and APS spatiotemporally to the appropriate site along the gastrointestinal tract. In an animal model of renal fibrosis (UUO rats), oral administration of the CPs ameliorated kidney histological pathology, reduced collagen deposition, and decreased the levels of inflammatory cytokines. The CPs also restored the disturbed gut microbiota induced by UUO surgery and protected the intestinal barrier.

Conclusion

The developed CPs pellets represent a promising strategy for efficiently delivering active components in traditional Chinese medicine formulas, offering an effective approach for treating CKD.

Diminished nuclear-localized β-adrenoceptor signalling activates YAP to promote kidney fibrosis in diabetic nephropathy

BACKGROUND AND PURPOSE

Diabetic nephropathy (DN) is a leading cause of chronic kidney disease (CKD), which is characterized by mesangial matrix expansion that involves dysfunctional mesangial cells (MCs). However, the underlying mechanisms remain unclear. This study aims to delineate the spatiotemporal contribution of adrenergic signalling in diabetic kidney fibrosis to reveal potential therapeutic targets.

EXPERIMENTAL APPROACH

A model of diabetic nephropathy was induced by in db/db mice. Gene expression in kidneys was profiled by RNA-seq analyses, western blot and immunostaining. Subcellular-localized fluorescence resonance energy transfer (FRET) biosensors determined adrenergic signalling microdomains in MCs. Effects of oral rolipram, a phosphodiesterase 4 (PDE4) inhibitor, on the model were measured.

KEY RESULTS

Our model exhibited impaired kidney function with elevated expression of adrenergic and fibrotic genes, including Adrb1, PDEs, Acta2 and Tgfβ. RNA-seq analysis revealed that MCs with dysregulated YAP pathway were crucial to the extracellular matrix secretion in kidneys from diabetic nephropathy patients. In cultured MCs, TGF-β promoted profibrotic gene transcription, which was regulated by nuclear-localized β-adrenoceptor signalling. Mechanistically, TGF-β treatment diminished nuclear-specific cAMP signalling in MCs and reduced PKA-dependent phosphorylation of YAP, leading to its activation. In parallel, db/db mouse kidneys showed increased expressions of PDE4B and PDE4D. Treatment with oral rolipram alleviated kidney fibrosis in db/db mice.

CONCLUSION AND IMPLICATIONS

Diabetic nephropathy impaired nuclear-localized β1-adrenoceptor-cAMP signalling microdomain through upregulating PDE4 expression, promoting fibrosis in MCs via PKA dephosphorylation-dependent YAP activation. Our results suggest PDE4 inhibition as a promising strategy for alleviating kidney fibrosis in diabetic nephropathy.

Repair and regeneration: ferroptosis in the process of remodeling and fibrosis in impaired organs

As common clinical-pathological processes, wound healing and tissue remodelling following injury or stimulation are essential topics in medical research. Promoting the effective healing of prolonged wounds, improving tissue repair and regeneration, and preventing fibrosis are important and challenging issues in clinical practice. Ferroptosis, which is characterized by iron overload and lipid peroxidation, is a nontraditional form of regulated cell death. Emerging evidence indicates that dysregulated metabolic pathways and impaired iron homeostasis play important roles in various healing and regeneration processes via ferroptosis. Thus, we review the intrinsic mechanisms of tissue repair and remodeling via ferroptosis in different organs and systems under various conditions, including the inflammatory response in skin wounds, remodeling of joints and cartilage, and fibrosis in multiple organs. Additionally, we summarize the common underlying mechanisms, key molecules, and targeted drugs for ferroptosis in repair and regeneration. Finally, we discuss the potential of therapeutic agents, small molecules, and novel materials emerging for targeting ferroptosis to promote wound healing and tissue repair and attenuate fibrosis.

The role of Klotho and sirtuins in sleep-related cardiovascular diseases: a review study

The prevalence of sleep disorders has been reported from 1.6% to 56.0%, worldwide. Sleep deprivation causes cardiovascular diseases (CVDs) including atherosclerosis, vascular aging, hypertension, heart dysfunction, reduced heart rate variability, and cardiac arrhythmia. Reduced tissue oxygen causes various CVDs by activating pro-inflammatory factors and increasing oxidative stress. Sleep disorders are more important and prevalent in older people and cause more severe cardiovascular complications. On the other hand, the reduction of Klotho level, an age-dependent protein whose expression decreases with age, is associated with age-related diseases. Sirtuins, class III histone deacetylases, also are among the essential factors in postponing cellular aging and increasing the lifespan of organisms, and they do this by regulating different pathways in the cell. Sirtuins and Klotho play an important role in the pathophysiology of CVDS and both have anti-oxidative stress and anti-inflammatory activity. Studies have shown that the levels of Klotho and sirtuins are altered in sleep disorders. In this article, alterations of Klotho and sirtuins in sleep disorders and in the development of sleep-related CVDs were reviewed and the possible signaling pathways were discussed. The inclusion criteria were studies with keywords of different types of sleep disorders and CVDs, klotho, SIRT1-7, and sirtuins in PubMed, Scopus, Embase، Science Direct، Web of Sciences and Google Scholar by the end of 2023. The studies revealed there is a bidirectional relationship between sleep disorders and the serum and tissue levels of Klotho and sirtuins and sleep related-CVDs.

Mesenchymal stem cell-derived exosomes as cell free nanotherapeutics and nanocarriers

Many strategies for regenerating the damaged tissues or degenerating cells are employed in regenerative medicine. Stem cell technology is a modern strategy of the recent approaches, particularly the use of mesenchymal stem cells (MCSs). The ability of MSCs to differentiate as well as their characteristic behaviour as paracrine effector has established them as key elements in tissue repair. Recently, extracellular vesicles (EVs) shed by MSCs have emerged as a promising cell free therapy. This comprehensive review encompasses MSCs-derived exosomes and their therapeutic potential as nanotherapeutics. We also discuss their potency as drug delivery nano-carriers in comparison with liposomes. A better knowledge of EVs behaviour in vivo and of their mechanism of action are key to determine parameters of an optimal formulation in pilot studies and to establish industrial processes.

Podocyte-targeted therapies - progress and future directions

Podocytes are the key target cells for injury across the spectrum of primary and secondary proteinuric kidney disorders, which account for up to 90% of cases of kidney failure worldwide. Seminal experimental and clinical studies have established a causative link between podocyte depletion and the magnitude of proteinuria in progressive glomerular disease. However, no substantial advances have been made in glomerular disease therapies, and the standard of care for podocytopathies relies on repurposed immunosuppressive drugs. The past two decades have seen a remarkable expansion in understanding of the mechanistic basis of podocyte injury, with prospects increasing for precision-based treatment approaches. Dozens of disease-causing genes with roles in the pathogenesis of clinical podocytopathies have been identified, as well as a number of putative glomerular permeability factors. These achievements, together with the identification of novel targets of podocyte injury, the development of potential approaches to harness the endogenous podocyte regenerative potential of progenitor cell populations, ongoing clinical trials of podocyte-specific pharmacological agents and the development of podocyte-directed drug delivery systems, contribute to an optimistic outlook for the future of glomerular disease therapy.

Novel therapeutic strategies and drugs for idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease of unknown etiology. Currently, drugs used to treat IPF in clinical practice exhibit severe side effects and limitations. To address these issues, this paper discusses the therapeutic effects of preclinical targeted drugs (such as STAT3 and TGF-β/Smad pathway inhibitors, chitinase inhibitors, PI3K and phosphodiesterase inhibitors, etc.) and natural products on IPF. Through a summary of current research progress, it is found that natural products possess multitarget effects, stable therapeutic efficacy, low side effects, and nondrug dependence. Furthermore, we discuss the significant prospects of natural product molecules in combating fibrosis by influencing the immune system, expecting that current analytical data will aid in the development of new drugs or the investigation of active ingredients in natural products for potential IPF treatments in the future.