Rac-GTPase promotes fibrotic TGF-β1 signaling and chronic kidney disease via EGFR, p53, and Hippo/YAP/TAZ pathways

Analysis of prognostic value of lactate metabolism-related genes in ovarian cancer based on bioinformatics

BACKGROUND

Recent studies have provided evidence supporting the functional role and mechanism of lactate in suppressing anticancer immunity. However, there is no systematic analysis of lactate metabolism-related genes (LMRGs) and ovarian cancer (OV) prognosis.

RESULTS

Six genes (CCL18, CCND1, MXRA5, NRBP2, OLFML2B and THY1) were selected as prognostic genes and a prognostic model was utilized. Kaplan-Meier (K-M) and Receiver Operating Characteristic (ROC) analyses were further performed and indicated that the prognostic model was effective. Subsequently, the neoplasm_cancer_status and RiskScore were determined as independent prognostic factors, and a nomogram was established with relatively accurate forecasting ability. Additionally, 2 types of immune cells (Central memory CD8 T cell and Immature B cell), 4 types of immune functions (APC co inhibition, DCs, Tfh and Th1 cells), 9 immune checkpoints (BTLA, CTLA4, IDO1, LAG3, VTCN1, CXCL10, CXCL9, IFNG, CD27) and tumor immune dysfunction and exclusion (TIDE) scores were significantly different between risk groups. The expression of 6 genes were verified by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) and the expression of 6 genes were higher in the high-grade serous carcinoma (HGSC) samples.

CONCLUSION

A prognostic model related to lactate metabolism was established for OV based on six genes (CCL18, CCND1, MXRA5, NRBP2, OLFML2B and THY1) that could provide new insights into therapy.

GSK343 modulates macrophage M2 polarization through the EZH2/MST1/YAP1 signaling axis to mitigate neurological damage induced by hypercalcemia in CKD mice

Chronic kidney disease (CKD) often culminates in hypercalcemia, instigating severe neurological injuries that are not yet fully understood. This study unveils a mechanism, where GSK343 ameliorates CKD-induced neural damage in mice by modulating macrophage polarization through the EZH2/MST1/YAP1 signaling axis. Specifically, GSK343 downregulated the expression of histone methyltransferase EZH2 and upregulated MST1, which suppressed YAP1, promoting M2 macrophage polarization and thereby, alleviating neural injury in hypercalcemia arising from renal failure. This molecular pathway introduced herein not only sheds light on the cellular machinations behind CKD-induced neurological harm but also paves the way for potential therapeutic interventions targeting the identified axis, especially considering the M2 macrophage polarization as a potential strategy to mitigate hypercalcemia-induced neural injuries.

PDGFβ receptor-targeted delivery of truncated transforming growth factor β receptor type II for improving the in vitro and in vivo anti-renal fibrosis activity via strong inactivation of TGF-β1/Smad signaling pathway

Truncated transforming growth factor β receptor type II (tTβRII), serving as a trap for binding excessive transforming growth factor β1 (TGF-β1) by means of competing with wild-type TβRII, is a promising strategy for the treatment of kidney fibrosis. Platelet-derived growth factor β receptor (PDGFβR) is highly expressed in interstitial myofibroblasts in kidney fibrosis. This study identified the interaction between a novel tTβRII variant Z-tTβRII (PDGFβR-specific affibody ZPDGFβR fused to the N-terminus of tTβRII) and TGF-β1. Moreover, Z-tTβRII highly targeted to TGF-β1-activated NIH3T3 cells and UUO-induced fibrotic kidney, but less to normal cells, tissues, and organs. Furthermore, Z-tTβRII significantly inhibited cell proliferation and migration, and reduced fibrosis markers expression and phosphorylation level of Smad2/3 in activated NIH3T3 cells. Meanwhile, Z-tTβRII markedly alleviated the kidney histopathology and fibrotic responses, and inhibited the TGF-β1/Smad signaling pathway in UUO mice. Besides, Z-tTβRII showed good safety performance in the treatment of UUO mice. In conclusion, these results demonstrated that Z-tTβRII may be a potential candidate for a targeting therapy on renal fibrosis due to the high potential of fibrotic kidney-targeting and strong anti-renal fibrosis activity.

Loss of the centrosomal protein ALMS1 alters lipid metabolism and the regulation of extracellular matrix-related processes

BACKGROUND

Alström syndrome (ALMS) is a rare autosomal recessive disease that is associated with mutations in ALMS1 gene. The main clinical manifestations of ALMS are retinal dystrophy, obesity, type 2 diabetes mellitus, dilated cardiomyopathy and multi-organ fibrosis, characteristic in kidneys and liver. Depletion of the protein encoded by ALMS1 has been associated with the alteration of different processes regulated via the primary cilium, such as the NOTCH or TGF-β signalling pathways. However, the cellular impact of these deregulated pathways in the absence of ALMS1 remains unknown.

METHODS

In this study, we integrated RNA-seq and proteomic analysis to determine the gene expression profile of hTERT-BJ-5ta ALMS1 knockout fibroblasts after TGF-β stimulation. In addition, we studied alterations in cross-signalling between the TGF-β pathway and the AKT pathway in this cell line.

RESULTS

We found that ALMS1 depletion affects the TGF-β pathway and its cross-signalling with other pathways such as PI3K/AKT, EGFR1 or p53. In addition, alterations associated with ALMS1 depletion clustered around the processes of extracellular matrix regulation and lipid metabolism in both the transcriptome and proteome. By studying the enriched pathways of common genes differentially expressed in the transcriptome and proteome, collagen fibril organisation, β-oxidation of fatty acids and eicosanoid metabolism emerged as key processes altered by the absence of ALMS1. Finally, an overactivation of the AKT pathway was determined in the absence of ALMS1 that could be explained by a decrease in PTEN gene expression.

CONCLUSION

ALMS1 deficiency disrupts cross-signalling between the TGF-β pathway and other dependent pathways in hTERT-BJ-5ta cells. Furthermore, altered cross-signalling impacts the regulation of extracellular matrix-related processes and fatty acid metabolism, and leads to over-activation of the AKT pathway.

Epidermal growth factor receptor activation is essential for kidney fibrosis development

Fibrosis is the progressive accumulation of excess extracellular matrix and can cause organ failure. Fibrosis can affect nearly every organ including kidney and there is no specific treatment currently. Although Epidermal Growth Factor Receptor (EGFR) signaling pathway has been implicated in development of kidney fibrosis, underlying mechanisms by which EGFR itself mediates kidney fibrosis have not been elucidated. We find that EGFR expression increases in interstitial myofibroblasts in human and mouse fibrotic kidneys. Selective EGFR deletion in the fibroblast/pericyte population inhibits interstitial fibrosis in response to unilateral ureteral obstruction, ischemia or nephrotoxins. In vivo and in vitro studies and single-nucleus RNA sequencing analysis demonstrate that EGFR activation does not induce myofibroblast transformation but is necessary for the initial pericyte/fibroblast migration and proliferation prior to subsequent myofibroblast transformation by TGF-ß or other profibrotic factors. These findings may also provide insight into development of fibrosis in other organs and in other conditions.

Combined inactivation of RB and Hippo converts differentiating Drosophila photoreceptors into eye progenitor cells through derepression of homothorax

The retinoblastoma (RB) and Hippo pathways interact to regulate cell proliferation and differentiation. However, the mechanism of interaction is not fully understood. Drosophila photoreceptors with inactivated RB and Hippo pathways specify normally but fail to maintain their neuronal identity and dedifferentiate. We performed single-cell RNA sequencing to elucidate the cause of dedifferentiation and to determine the fate of these cells. We find that dedifferentiated cells adopt a progenitor-like fate due to inappropriate activation of the retinal differentiation suppressor homothorax (hth) by Yki/Sd. This results in the activation of a distinct Yki/Hth transcriptional program, driving photoreceptor dedifferentiation. We show that Rbf physically interacts with Yki and, together with the GAGA factor, inhibits the hth expression. Thus, RB and Hippo pathways cooperate to maintain photoreceptor differentiation by preventing inappropriate expression of hth in differentiating photoreceptors. Our work highlights the importance of both RB and Hippo pathway activities for maintaining the state of terminal differentiation.

PCLLA-nanoHA Bone Substitute Promotes M2 Macrophage Polarization and Improves Alveolar Bone Repair in Diabetic Environments

The utilization of bioresorbable synthetic bone substitutes with immunomodulatory properties has gained significant attention in dental clinical applications for the absorption of alveolar bone induced by orthodontic treatment. In this study, we developed two distinct materials: a conventional hydroxyapatite (HA) bone powder comprised of hydroxyapatite particles and nanoHA embedded within a poly(caprolactone-co-lactide) (PCLLA) elastomeric matrix. We assessed the physicochemical characteristics of the bone substitute, specifically focusing on its composition and the controlled release of ions. Our findings show that PCLLA-nanoHA has deformable properties under 40 N, and a significant release of Ca and P elements was noted after 7 days in aqueous settings. Moreover, at the protein and gene expression levels, PCLLA-nanoHA enhances the capacity of macrophages to polarize towards an M2 phenotype in vitro. In vivo, PCLLA-nanoHA exhibits comparable effects to standard HA bone powder in terms of promoting alveolar bone regeneration. Extensive investigations reveal that PCLLA-nanoHA surpasses the commonly employed HA bone powder in stimulating bone tissue repair in diabetic mice. We have identified that PCLLA-nanoHA regulates macrophage M2 polarization by activating the PI3K/AKT and peroxisome proliferator-activated receptor gamma (PPAR) signaling pathways, thereby facilitating a favorable local immune microenvironment conducive to bone repair and regeneration. Our findings suggest that PCLLA-nanoHA presents itself as a promising bioresorbable bone substitute with properties that promote macrophage M2 polarization, particularly in the context of regulating the local microenvironment of alveolar bone in diabetic mice, potentially facilitating bone tissue regeneration.

N6-methyladenosine methylation in kidney injury

Multiple mechanisms are involved in kidney damage, among which the role of epigenetic modifications in the occurrence and development of kidney diseases is constantly being revealed. However, N6-methyladenosine (M6A), a well-known post-transcriptional modification, has been regarded as the most prevalent epigenetic modifications in higher eukaryotic, which is involved in various biological processes of cells such as maintaining the stability of mRNA. The role of M6A modification in the mechanism of kidney damage has attracted widespread attention. In this review, we mainly summarize the role of M6A modification in the progression of kidney diseases from the following aspects: the regulatory pattern of N6-methyladenosine, the critical roles of N6-methyladenosine in chronic kidney disease, acute kidney injury and renal cell carcinoma, and then reveal its potential significance in the diagnosis and treatment of various kidney diseases. A better understanding of this field will be helpful for future research and clinical treatment of kidney diseases.

Pregnane X receptor activation alleviates renal fibrosis in mice via interacting with p53 and inhibiting the Wnt7a/β-catenin signaling

Renal fibrosis is a common pathological feature of chronic kidney disease (CKD) with various etiologies, which seriously affects the structure and function of the kidney. Pregnane X receptor (PXR) is a member of the nuclear receptor superfamily and plays a critical role in regulating the genes related to xenobiotic and endobiotic metabolism in mammals. Previous studies show that PXR is expressed in the kidney and has protective effect against acute kidney injury (AKI). In this study, we investigated the role of PXR in CKD. Adenine diet-induced CKD (AD) model was established in wild-type and PXR humanized (hPXR) mice, respectively, which were treated with pregnenolone-16α-carbonitrile (PCN, 50 mg/kg, twice a week for 4 weeks) or rifampicin (RIF, 10 mg·kg-1·d-1, for 4 weeks). We showed that both PCN and RIF, which activated mouse and human PXR, respectively, improved renal function and attenuated renal fibrosis in the two types of AD mice. In addition, PCN treatment also alleviated renal fibrosis in unilateral ureter obstruction (UUO) mice. On the contrary, PXR gene deficiency exacerbated renal dysfunction and fibrosis in both adenine- and UUO-induced CKD mice. We found that PCN treatment suppressed the expression of the profibrotic Wnt7a and β-catenin in AD mice and in cultured mouse renal tubular epithelial cells treated with TGFβ1 in vitro. We demonstrated that PXR was colocalized and interacted with p53 in the nuclei of tubular epithelial cells. Overexpression of p53 increased the expression of Wnt7a, β-catenin and its downstream gene fibronectin. We further revealed that p53 bound to the promoter of Wnt7a gene to increase its transcription and β-catenin activation, leading to increased expression of the downstream profibrotic genes, which was inhibited by PXR. Taken together, PXR activation alleviates renal fibrosis in mice via interacting with p53 and inhibiting the Wnt7a/β-catenin signaling pathway.

Mechanism of transforming growth factor-1 induce renal fibrosis based on transcriptome sequencing analysis

OBJECTIVES

To explore the mechanism of transforming growth factor-β1 (TGF-β1) induce renal fibrosis.

METHODS

Renal fibroblast NRK-49F cells treated with and without TGF-β1 were subjected to RNA-seq analysis. DESeq2 was used for analysis. Differentially expressed genes were screened with the criteria of false discovery rate<0.05 and l o g 2 F C >1. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for differentially expressed genes. Genes encoding transcription factors were further screened for differential expression genes. Then, the expression of these genes during renal fibrosis was verified using unilateral ureteral obstruction (UUO)-induced mouse renal fibrosis model and a public gene expression dataset (GSE104954).

RESULTS

After TGF-β1 treatment for 6, 12 and 24 h, 552, 1209 and 1028 differentially expressed genes were identified, respectively. GO analysis indicated that these genes were significantly enriched in development, cell death, and cell migration. KEGG pathway analysis showed that in the early stage of TGF-β1 induction (TGF-β1 treatment for 6 h), the changes in Hippo, TGF-β and Wnt signaling pathways were observed, while in the late stage of TGF-β1 induction (TGF-β1 treatment for 24 h), the changes of extracellular matrix-receptor interaction, focal adhesion and adherens junction were mainly enriched. Among the 291 up-regulated differentially expressed genes treated with TGF-β1 for 6 h, 13 genes (Snai1, Irf8, Bhlhe40, Junb, Arid5a, Vdr, Lef1, Ahr, Foxo1, Myc, Tcf7, Foxc2, Glis1) encoded transcription factors. Validation in a cell model showed that TGF-β1 induced expression of 9 transcription factors (encoded by Snai1, Irf8, Bhlhe40, Junb, Arid5a, Vdr, Lef1, Myc, Tcf7), while the expression levels of the other 4 genes did not significantly change after TGF-β1 treatment. Validation results in UUO-induced mouse renal fibrosis model showed that Snai1, Irf8, Bhlhe40, Junb, Arid5a, Myc and Tcf7 were up-regulated after UUO, Vdr was down-regulated and there was no significant change in Lef1. Validation based on the GSE104954 dataset showed that IRF8 was significantly overexpressed in the renal tubulointerstitium of patients with diabetic nephropathy or IgA nephropathy, MYC was highly expressed in diabetic nephropathy, and the expressions of the other 7 genes were not significantly different compared with the control group.

CONCLUSIONS

TGF-β1 induces differentially expressed genes in renal fibroblasts, among which Irf8 and Myc were identified as potential targets of chronic kidney disease and renal fibrosis.

Isoliensinine Attenuates Renal Fibrosis and Inhibits TGF-β1/Smad2/3 Signaling Pathway in Spontaneously Hypertensive Rats

Purpose

This study aimed to investigate the molecular mechanisms of isoliensinine, a kind of bibenzyl isoquinoline alkaloid which isolated from a TCM named Lotus Plumule (Nelumbo nucifera Gaertn), in treating renal interstitial fibrosis (RIF) by using RNA sequencing, KEGG analysis and in vivo experimental approaches.

Methods

Spontaneous hypertension rats (SHRs) were randomly assigned into five groups, consisting of SHR, SHR+Isoliensinine-L (2.5 mg/kg/day), SHR+Isoliensinine-M (5 mg/kg/day), SHR+Isoliensinine-H (10 mg/kg/day), and SHR+Valsartan (10 mg/kg/day) groups (n = 6 for each group). A control group of Wistar Kyoto rats (n = 6) was also included. Rats were treated intragastrically with isoliensinine, valsartan, or double-distilled water of equal volume for 10 weeks. To examine the therapeutic impact on hypertensive renal injury, fibrosis, and its underlying mechanisms, multiple techniques were employed, including hematoxylin and eosin staining, Masson trichrome staining, RNA sequencing, gene ontology (GO) function and pathway enrichment analysis and immunohistochemistry.

Results

Resultantly, the use of isoliensinine at different concentrations or valsartan showed significant improvement in renal pathological injury in SHRs. RNA sequencing and KEGG analysis uncovered 583 differentially expressed transcripts and pathways enriched in collagen formation and ECM-receptor interaction after treatment with isoliensinine. There was also a reduction in the increase of collagen and upregulation of collagen I & III, TGF-β1, p-Smad2, and p-Smad3 in the renal tissue of SHRs. Thus, isoliensinine ameliorated renal injury and collagen deposition in hypertensive rats, and inhibiting the activation of the TGF-β1/Smad2/3 pathway might be one of the underlying mechanisms.

Conclusion

This study showed that treatment with isoliensinine effectively reduced the renal injury and fibrosis in SHRs. In addition, isoliensinine inhibited the TGF-β1/Smad2/3 signaling in-vivo. These findings provided strong evidence for the therapeutic benefits of isoliensinine in combating renal injury and fibrosis.

YAP/TAZ: Molecular pathway and disease therapy

The Yes-associated protein and its transcriptional coactivator with PDZ-binding motif (YAP/TAZ) are two homologous transcriptional coactivators that lie at the center of a key regulatory network of Hippo, Wnt, GPCR, estrogen, mechanical, and metabolism signaling. YAP/TAZ influences the expressions of downstream genes and proteins as well as enzyme activity in metabolic cycles, cell proliferation, inflammatory factor expression, and the transdifferentiation of fibroblasts into myofibroblasts. YAP/TAZ can also be regulated through epigenetic regulation and posttranslational modifications. Consequently, the regulatory function of these mechanisms implicates YAP/TAZ in the pathogenesis of metabolism-related diseases, atherosclerosis, fibrosis, and the delicate equilibrium between cancer progression and organ regeneration. As such, there arises a pressing need for thorough investigation of YAP/TAZ in clinical settings. In this paper, we aim to elucidate the signaling pathways that regulate YAP/TAZ and explore the mechanisms of YAP/TAZ-induce diseases and their potential therapeutic interventions. Furthermore, we summarize the current clinical studies investigating treatments targeting YAP/TAZ. We also address the limitations of existing research on YAP/TAZ and propose future directions for research. In conclusion, this review aims to provide fresh insights into the signaling mediated by YAP/TAZ and identify potential therapeutic targets to present innovative solutions to overcome the challenges associated with YAP/TAZ.

Slowing the Progression of Diabetic Kidney Disease

Diabetes is the most frequent cause of kidney disease that progresses to end-stage renal disease worldwide, and diabetic kidney disease is significantly related to unfavorable cardiovascular outcomes. Since the 1990s, specific therapies have emerged and been approved to slow the progression of diabetic kidney disease, namely, renin-angiotensin-aldosterone system blockers (including angiotensin-converting enzyme inhibitors (ACEi) angiotensin receptor blockers (ARBs), the non-steroidal mineralocorticoid receptor antagonist (NS-MRA), finerenone, and sodium-glucose cotransporter-2 (SGLT2) inhibitors). Mechanistically, these different classes of agents bring different anti-inflammatory, anti-fibrotic, and complementary hemodynamic effects to patients with diabetic kidney disease such that they have additive benefits on slowing disease progression. Within the coming year, there will be data on renal outcomes using the glucagon-like peptide-1 receptor agonist, semaglutide. All the aforementioned medications have also been shown to improve cardiovascular outcomes. Thus, all three classes (maximally dosed ACEi or ARB, low-dose SGLT-2 inhibitors, and the NS-MRA, finerenone) form the "pillars of therapy" such that, when used together, they maximally slow diabetic kidney disease progression. Ongoing studies aim to expand these pillars with additional medications to potentially normalize the decline in kidney function and reduce associated cardiovascular mortality.

An atlas of healthy and injured cell states and niches in the human kidney

Understanding kidney disease relies on defining the complexity of cell types and states, their associated molecular profiles and interactions within tissue neighbourhoods1. Here we applied multiple single-cell and single-nucleus assays (>400,000 nuclei or cells) and spatial imaging technologies to a broad spectrum of healthy reference kidneys (45 donors) and diseased kidneys (48 patients). This has provided a high-resolution cellular atlas of 51 main cell types, which include rare and previously undescribed cell populations. The multi-omic approach provides detailed transcriptomic profiles, regulatory factors and spatial localizations spanning the entire kidney. We also define 28 cellular states across nephron segments and interstitium that were altered in kidney injury, encompassing cycling, adaptive (successful or maladaptive repair), transitioning and degenerative states. Molecular signatures permitted the localization of these states within injury neighbourhoods using spatial transcriptomics, while large-scale 3D imaging analysis (around 1.2 million neighbourhoods) provided corresponding linkages to active immune responses. These analyses defined biological pathways that are relevant to injury time-course and niches, including signatures underlying epithelial repair that predicted maladaptive states associated with a decline in kidney function. This integrated multimodal spatial cell atlas of healthy and diseased human kidneys represents a comprehensive benchmark of cellular states, neighbourhoods, outcome-associated signatures and publicly available interactive visualizations.

Hippo signaling in acute kidney injury to chronic kidney disease transition: current understandings and future targets

Acute kidney injury (AKI)-to-chronic kidney disease (CKD) transition is a slow but persistent progression toward end-stage kidney disease. Earlier reports have shown that Hippo components, such as Yes-associated protein (YAP) and its homolog TAZ (Transcriptional coactivator with PDZ-binding motif), regulate inflammation and fibrogenesis during the AKI-to-CKD transition. Notably, the roles and mechanisms of Hippo components vary during AKI, AKI-to-CKD transition, and CKD. Hence, it is important to understand these roles in detail. This review addresses the potential of Hippo regulators or components as future therapeutic targets for halting the AKI-to-CKD transition.

Transcriptomic Evidence of Hypothalamus for Maternal Fructose Exposure Induced Offspring Hypertension through AT1R/TLR4 Pathway

Maternal fructose exposure during pregnancy and lactation has been shown to contribute to hypertension in offspring, with long-term effects on hypothalamus development. However, the underlying mechanisms remain unclear. In this study, we used the tail-cuff method to evaluate the effects of maternal fructose drinking exposure on offspring blood pressure levels at postpartum day 21 (PND21) and postpartum day 60 (PND60). We employed Oxford Nanopore Technologies (ONT) full-length RNA sequencing to investigate the developmental programming of the PND60 offspring's hypothalamus and confirmed the presence of the AT1R/TLR4 pathway using western blot and immunofluorescence. Our findings demonstrated that maternal fructose exposure significantly increased blood pressure in PND60 offspring but not in PND21 offspring. Additionally, we observed transcriptome-wide alterations in the hypothalamus of PND60 offspring following maternal fructose exposure. Overall, our study provides evidence that maternal fructose exposure during pregnancy and lactation may alter the transcriptome-wide of offspring hypothalamus and activate the AT1R/TLR4 pathway, leading to hypertension. These findings may have important implications for the prevention and treatment of hypertension-related diseases in offspring exposed to excessive fructose during pregnancy and lactation.

Polystyrene-microplastics and DEHP co-exposure induced DNA damage, cell cycle arrest and necroptosis of ovarian granulosa cells in mice by promoting ROS production

The joint pollution of microplastics (MPs) and di-(2-ethylhexyl) phthalic acid (DEHP) often occurs, and consequently poses a serious threat to human and animal health, which has attracted widespread attention. However, the damage to the female mammalian ovary caused by the single exposure and co-exposure of MPs and DEHP and its specific mechanisms are not clear. Here, we established mouse models of single and co-exposures to polystyrene-microplastics (PS-MPs) and DEHP. The results showed that exposed to 100 mg/L PS-MPs and 200 mg/kg DEHP for 35 days destroyed the ovarian granulosa cell layer of mice, leading to follicular fragmentation and atresia. We cultured ovary granulosa cells in vitro to perform further mechanism studies and found that PS-MPs and DEHP had synergistic effects. Both of them promoted the excessive production of ROS and induced oxidative stress by triggering the CNR1/CRBN/YY1/CYP2E1 signaling axis, which in turn caused DNA oxidative damage. Additionally, we provided compelling evidence that oxidative stress mediated-hippo signaling pathway played a critical role in PS-MPs and DEHP caused ovary damage, resulting in ovarian granulosa cell cycle arrest and necroptosis. Using oxidative stress inhibitor AM251 or DAS could reverse these changes markedly and alleviate the reproductive toxicity caused by PS-MPs and DEHP, effectively. Overall, these results demonstrated that co-exposure of PS-MPs and DEHP adversely affected the integrity of ovary granulosa cell layer, resulting in DNA oxidative damage, cell cycle arrest and increased necroptosis of mouse ovarian granulosa cells by inducing oxidative stress. Our study shed new light on the co-exposure toxicity of PS-MPs and DEHP, provided novel insights for the reproductive toxicity of PS-MPs combined exposure with DEHP in female animals from a new free radical generation pathway perspective.

Combined inactivation of RB and Hippo pathways converts differentiating photoreceptors into eye progenitor cells through derepression of homothorax

The RB and Hippo pathways interact to regulate cell proliferation and differentiation. However, their mechanism of interaction is not fully understood. Drosophila photoreceptors with inactivated RB and Hippo pathways specify normally but fail to maintain neuronal identity and dedifferentiate. We performed single-cell RNA-sequencing to elucidate the cause of dedifferentiation and the fate of these cells. We find that dedifferentiated cells adopt a progenitor-like fate due to inappropriate activation of the retinal differentiation suppressor homothorax (hth) by Yki/Sd. This results in activation of the Yki/Hth transcriptional program, driving photoreceptor dedifferentiation. We show that Rbf physically interacts with Yki which, together with the GAGA factor, inhibits hth expression. Thus, RB and Hippo pathways cooperate to maintain photoreceptor differentiation by preventing inappropriate expression of hth in differentiating photoreceptors. Our work accentuates the importance of both RB and Hippo pathway activity for maintaining the state of terminal differentiation.

Molecular Targets for Nonhormonal Treatment Based on a Multistep Process of Adenomyosis Development

Adenomyosis is an estrogen-dependent gynecologic disease characterized by the presence of endometrial tissue within the myometrium. Adenomyosis presents with abnormal uterine bleeding, pelvic pains, and infertility. This review aimed to investigate the major estrogen downstream effectors involved in the process of adenomyosis development and their potential use for nonhormonal treatment. A literature search was performed for preclinical and clinical studies published between January 2010 and November 2021 in the PubMed and Google Scholar databases using a combination of specific terms. Adenomyosis presents with a wide spectrum of clinical manifestations from asymptomatic to severe through a complex process involving a series of molecular changes associated with inflammation, invasion, angiogenesis, and fibrosis. Adenomyosis may develop through a multistep process, including the acquisition of (epi)genetic mutations, tissue injury caused at the endometrial-myometrial interface, inside-to-outside invasion (from the endometrial side into the uterine wall), or outside-to-inside invasion (from the serosal side into the uterine wall), and epithelial-mesenchymal transition, tissue repair or remodeling in the myometrium. These processes can be regulated by increased estrogen biosynthesis and progesterone resistance. The expression of estrogen downstream effectors associated with persistent inflammation, fragile and more permeable vessel formation, and tissue injury and remodeling may be correlated with dysmenorrhea, heavy menstrual bleeding, and infertility, respectively. Key estrogen downstream targets (e.g., WNT/β-catenin, transforming growth factor-β, and nuclear factor-κB) may serve as hub genes. We reviewed the molecular mechanisms underlying the development of adenomyosis and summarized potential nonhormonal therapies.

The Biology and Therapeutic Potential of the Src-YAP Axis in Non-Small Cell Lung Cancer (NSCLC)

Non-small cell lung cancer (NSCLC) is the most common lung cancer type which accounts for the majority (~85%) of all lung cancer cases [...].

Identifying the molecular mechanisms of sepsis-associated acute kidney injury and predicting potential drugs

Objective: To provide insights into the diagnosis and therapy of SA-AKI via ferroptosis genes. Methods: Based on three datasets (GSE57065, GSE30718, and GSE53771), we used weighted co-expression network analysis to identify the key regulators of SA-AKI, its potential biological functions, and constructed miRNA‒mRNA complex regulatory relationships. We also performed machine learning and in vitro cell experiments to identify ferroptosis genes that are significantly related to SA-AKI in the two datasets. The CIBERSORT algorithm evaluates the degree of infiltration of 22 types of immune cell. We compared the correlation between ferroptosis and immune cells by Pearson's correlation analysis and verified the key genes related to the immune response to reveal potential diagnostic markers. Finally, we predicted the effects of drugs and the potential therapeutic targets for septic kidney injury by pRRophetic. Results: We found 264 coDEGs involving 1800 miRNA molecules that corresponded to 210 coDEGs. The miRNA‒mRNA ceRNA interaction network was constructed to obtain the top-10 hub nodes. We obtained the top-20 ferroptosis genes, 11 of which were in the intersection. We also identified a relationship between ferroptosis genes and the immune cells in the AKI dataset, which showed that neutrophils were activated and that regulatory T cells were surpassed. Finally, we identified EHT1864 and salubrinal as potential therapeutic agents. Conclusion: This study demonstrated the roles of miR-650 and miR-296-3p genes in SA-AKI. Furthermore, we identified OLFM4, CLU, RRM2, SLC2A3, CCL5, ADAMTS1, and EPHX2 as potential biomarkers. The irregular immune response mediated by neutrophils and Treg cells is involved in the development of AKI and shows a correlation with ferroptosis genes. EHT 1864 and salubrinal have potential as drug candidates in patients with septic acute kidney injury.

The critical role of the Hippo signaling pathway in kidney diseases

The Hippo signaling pathway is involved in cell growth, proliferation, and apoptosis, and it plays a key role in regulating organ size, tissue regeneration, and tumor development. The Hippo signaling pathway also participates in the occurrence and development of various human diseases. Recently, many studies have shown that the Hippo pathway is closely related to renal diseases, including renal cancer, cystic kidney disease, diabetic nephropathy, and renal fibrosis, and it promotes the transformation of acute kidney disease to chronic kidney disease (CKD). The present paper summarizes and analyzes the research status of the Hippo signaling pathway in different kidney diseases, and it also summarizes the expression of Hippo signaling pathway components in pathological tissues of kidney diseases. In addition, the present paper discusses the positive therapeutic significance of traditional Chinese medicine (TCM) in regulating the Hippo signaling pathway for treating kidney diseases. This article introduces new targets and ideas for drug development, clinical diagnosis, and treatment of kidney diseases.

Tumor microenvironment in non-melanoma skin cancer resistance to photodynamic therapy

Non-melanoma skin cancer has recently seen an increase in prevalence, and it is estimated that this grow will continue in the coming years. In this sense, the importance of therapy effectiveness has increased, especially photodynamic therapy. Photodynamic therapy has attracted much attention as a minimally invasive, selective and repeatable approach for skin cancer treatment and prevention. Although its high efficiency, this strategy has also faced problems related to tumor resistance, where the tumor microenvironment has gained a well-deserved role in recent years. Tumor microenvironment denotes a wide variety of elements, such as cancer-associated fibroblasts, immune cells, endothelial cells or the extracellular matrix, where their interaction and the secretion of a wide diversity of cytokines. Therefore, the need of designing new strategies targeting elements of the tumor microenvironment to overcome the observed resistance has become evident. To this end, in this review we focus on the role of cancer-associated fibroblasts and tumor-associated macrophages in the resistance to photodynamic therapy. We are also exploring new approaches consisting in the combination of new and old drugs targeting these cells with photodynamic therapy to enhance treatment outcomes of non-melanoma skin cancer.

The Pro-Fibrotic Response to Lens Injury Is Signaled in a PI3K Isoform-Specific Manner

The signaling inputs that function to integrate biochemical and mechanical cues from the extracellular environment to alter the wound-repair outcome to a fibrotic response remain poorly understood. Here, using a clinically relevant post-cataract surgery wound healing/fibrosis model, we investigated the role of Phosphoinositide-3-kinase (PI3K) class I isoforms as potential signaling integrators to promote the proliferation, emergence and persistence of collagen I-producing alpha smooth muscle actin (αSMA+) myofibroblasts that cause organ fibrosis. Using PI3K isoform specific small molecule inhibitors, our studies revealed a requisite role for PI3K p110α in signaling the CD44+ mesenchymal leader cell population that we previously identified as resident immune cells to produce and organize a fibronectin-EDA rich provisional matrix and transition to collagen I-producing αSMA+ myofibroblasts. While the PI3K effector Akt was alone insufficient to regulate myofibroblast differentiation, our studies revealed a role for Rac, another potential PI3K effector, in this process. Our studies further uncovered a critical role for PI3K p110α in signaling the proliferation of CD44+ leader cells, which is important to the emergence and expansion of myofibroblasts. Thus, these studies identify activation of PI3K p110α as a critical signaling input following wounding to the development and progression of fibrotic disease.

Emerging role of tumor suppressor p53 in acute and chronic kidney diseases

p53 is a major regulator of cell cycle arrest, apoptosis, and senescence. While involvement of p53 in tumorigenesis is well established, recent studies implicate p53 in the initiation and progression of several renal diseases, which is the focus of this review. Ischemic-, aristolochic acid (AA) -, diabetic-, HIV-associated-, obstructive- and podocyte-induced nephropathies are accompanied by activation and/or elevated expression of p53. Studies utilizing chemical or renal-specific inhibition of p53 in mice confirm the pathogenic role of this transcription factor in acute kidney injury and chronic kidney disease. TGF-β1, NOX, ATM/ATR kinases, Cyclin G, HIPK, MDM2 and certain micro-RNAs are important determinants of renal p53 function in response to trauma. AA, cisplatin or TGF-β1-mediated ROS generation via NOXs promotes p53 phosphorylation and subsequent tubular dysfunction. p53-SMAD3 transcriptional cooperation downstream of TGF-β1 orchestrates induction of fibrotic factors, extracellular matrix accumulation and pathogenic renal cell communication. TGF-β1-induced micro-RNAs (such as mir-192) could facilitate p53 activation, leading to renal hypertrophy and matrix expansion in response to diabetic insults while AA-mediated mir-192 induction regulates p53 dependent epithelial G2/M arrest. The widespread involvement of p53 in tubular maladaptive repair, interstitial fibrosis, and podocyte injury indicate that p53 clinical targeting may hold promise as a novel therapeutic strategy for halting progression of certain acute and chronic renal diseases, which affect hundreds of million people worldwide.

The regulation of yes-associated protein/transcriptional coactivator with PDZ-binding motif and their roles in vascular endothelium

Normal endothelial function plays a pivotal role in maintaining cardiovascular homeostasis, while endothelial dysfunction causes the occurrence and development of cardiovascular diseases. Yes-associated protein (YAP) and its homolog transcriptional co-activator with PDZ-binding motif (TAZ) serve as crucial nuclear effectors in the Hippo signaling pathway, which are regulated by mechanical stress, extracellular matrix stiffness, drugs, and other factors. Increasing evidence supports that YAP/TAZ play an important role in the regulation of endothelial-related functions, including oxidative stress, inflammation, and angiogenesis. Herein, we systematically review the factors affecting YAP/TAZ, downstream target genes regulated by YAP/TAZ and the roles of YAP/TAZ in regulating endothelial functions, in order to provide novel potential targets and effective approaches to prevent and treat cardiovascular diseases.

Rac1 as a therapeutic anticancer target: Promises and limitations

Small molecule inhibitors of GTPases are increasingly considered for the treatment of multiple human pathologies. The GTPase Rac1 (Ras-related C3 botulinum toxin substrate 1) plays major roles in vital cellular processes, notably in the control cell motility and dynamic, the regulation of oxidative stress, and in inflammatory and immune surveillance. As such, Rac1 is viewed as a potential target to combat cancers but also diverse inflammatory, metabolic, neurodegenerative, respiratory, cardiovascular, viral, and parasitic diseases. Potent and selective Rac1 inhibitors have been identified and designed, such as compounds GYS32661 and MBQ-167 both in preclinical development for the treatment of advanced solid tumors. The pleiotropic roles and ubiquitous expression of the protein can be viewed as limitations for anticancer approaches. However, the frequent overexpression and/or hyperactivation of the Rac1 in difficult-to-treat chemoresistant cancers, make Rac1 an attractive target in oncology. The key roles of Rac1 in multiple cellular pathways, together with its major implications in carcinogenesis, tumor proliferation and metastasis, support the development of small molecule inhibitors. The challenge is high and the difficulty shall not be underestimated, but the target is innovative and promising in combination with chemo- and/or immuno-therapy. Opportunities and challenges associated with the targeting of Rac1 are discussed.

Deletion of STAT3 from Foxd1 cell population protects mice from kidney fibrosis by inhibiting pericytes trans-differentiation and migration

Signal transduction and activator of transcription 3 (STAT3) is a key transcription factor implicated in the pathogenesis of kidney fibrosis. Although Stat3 deletion in tubular epithelial cells is known to protect mice from fibrosis, vFoxd1 cells remains unclear. Using Foxd1-mediated Stat3 knockout mice, CRISPR, and inhibitors of STAT3, we investigate its function. STAT3 is phosphorylated in tubular epithelial cells in acute kidney injury, whereas it is expanded to interstitial cells in fibrosis in mice and humans. Foxd1-mediated deletion of Stat3 protects mice from folic-acid- and aristolochic-acid-induced kidney fibrosis. Mechanistically, STAT3 upregulates the inflammation and differentiates pericytes into myofibroblasts. STAT3 activation increases migration and profibrotic signaling in genome-edited, pericyte-like cells. Conversely, blocking Stat3 inhibits detachment, migration, and profibrotic signaling. Furthermore, STAT3 binds to the Collagen1a1 promoter in mouse kidneys and cells. Together, our study identifies a previously unknown function of STAT3 that promotes kidney fibrosis and has therapeutic value in fibrosis.

Comparative transcriptome analysis of miRNA in hydronephrosis male children caused by ureteropelvic junction obstruction with or without renal functional injury

MicroRNAs (miRNAs or miRs) are non-coding RNAs that contribute to pathological processes of various kidney diseases. Renal function injury represents a final common outcome of congenital obstructive nephropathy and has attracted a great deal of attention. However the molecular mechanisms are still not fully established. In this study, we compared transcriptome sequencing data of miRNAs of renal tissues from congenital hydronephrosis children with or without renal functional injury, in order to better understand whether microRNAs could play important roles in renal functional injury after ureteropelvic junction obstruction. A total of 22 microRNAs with significant changes in their expression were identified. Five microRNAs were up-regulated and 17 microRNAs were down-regulated in the renal tissues of the hydronephrosis patients with renal function injury compared with those without renal function injury. MicroRNA target genes were predicted by three major online miRNA target prediction algorithms, and all these mRNAs were used to perform the gene ontology analysis and Kyoto Encyclopedia of Gene and Genomes pathway analysis. Then, twelve candidate human and rat homologous miRNAs were selected for validation using RT-qPCR in vitro and in vivo; only miR-187-3p had a trend identical to that detected by the sequencing results among the human tissues, in vivo and in vitro experimental models. In addition, we found that the change of miR-187-3p in vivo was consistent with results in vitro models and showed a decrease trend in time dependence. These results provided a detailed catalog of candidate miRNAs to investigate their regulatory role in renal injury of congenital hydronephrosis, indicating that they may serve as candidate biomarkers or therapeutic targets in the future.

Disruption of LTBP4 Inhibition-Induced TGFβ1 Activation Promoted Cell Proliferation and Metastasis in Skin Melanoma by Inhibiting the Activation of the Hippo-YAP1 Signaling Pathway

Melanoma is a malignant tumor derived from melanocytes, which is the most fatal skin cancer. The present study aimed to explore and elucidate the candidate genes in melanoma and its underlying molecular mechanism. A total of 1,156 differentially expressed genes were obtained from the GSE46517 dataset of Gene Expression Omnibus database using the package “limma” in R. Based on two algorithms (LASSO and SVM-RFE), we obtained three candidate DEGs (LTBP4, CDHR1, and MARCKSL1). Among them, LTBP4 was identified as a diagnostic marker of melanoma (AUC = 0.985). Down-regulation of LTBP4 expression was identified in melanoma tissues and cells, which predicted poor prognosis of patients with melanoma. Cox analysis results discovered that LTBP4 with low expression was an independent prognostic factor for overall survival in patients with melanoma. LTBP4 inhibition reduced cell apoptosis and promoted cell proliferation and metastasis. These changes were correlated with the expression levels of caspase-3, Ki67 and E-cadherin. Further, as indicated by tumor formation study of nude mice, LTBP4 silencing improved the tumorigenic ability of melanoma cells. Knockdown of LTBP4 increased the percentage of active TGFβ1 secreted by melanoma cells. CTGF, Gyr61, and Birc5 expression levels were reduced, YAP1 phosphorylation was inhibited, and YAP1 was translocated from the cytoplasm to the nucleus in melanoma cells treated with TGF-β1. These effects were reversed by LTBP4 overexpression. As evidenced by immunofluorescent staining, Western blotting and luciferase reporter assay, LTBP4 overexpression activated the Hippo signaling pathway, which was characterized by the increased nuclear-cytoplasmic translocation of YAP1 and the enhanced phosphorylation of YAP1, MST1, and MOB1. In addition, the effects of LTBP4 overexpression on inhibiting CTGF, Cyr61 and Birc5 expression, promoting the apoptosis, and inhibiting the metastasis and proliferation of melanoma cells were reversed by the overexpression of YAP1 or MST1. In conclusion, the LTBP4-TGFβ1-Hippo-YAP1 axis is a critical pathway for the progression of skin melanoma.

CGRP: A New Endogenous Cell Stemness Maintenance Molecule

Stem cells have the ability of self-replication and multidirectional differentiation, but the mechanism of how stem cells “maintain” this ability and how to “decide” to give up this state and differentiate into cells with specific functions is still unknown. The Nobel Prize in physiology and medicine in 2021 was awarded to “temperature and tactile receptor,” which made the pain receptor TRPV1-calcitonin gene-related peptide (CGRP) pathway active again. The activation and blocking technology of CGRP has been applied to many clinical diseases. CGRP gene has complex structure and transcription process, with multiple methylation and other modification sites. It has been considered as a research hotspot and difficulty since its discovery. Drug manipulation of TRPV1 and inhibition of CGRP might improve metabolism and prolong longevity. However, whether the TRPV1-neuropeptide-CGRP pathway is directly or indirectly involved in stem cell self-replication and multidirectional differentiation is unclear. Recent studies have found that CGRP is closely related to the migration and differentiation of tumor stem cells, which may be realized by turning off or turning on the CGRP gene expression in stem cells and activating a variety of ways to regulate stem cell niches. In this study, we reviewed the advances in researches concentrated on the biological effects of CGRP as a new endogenous switching of cell stemness.

Rho GTPases in kidney physiology and diseases

Rho family GTPases are molecular switches best known for their pivotal role in dynamic regulation of the actin cytoskeleton, but also of cellular morphology, motility, adhesion and proliferation. The prototypic members of this family (RhoA, Rac1 and Cdc42) also contribute to the normal kidney function and play important roles in the structure and function of various kidney cells including tubular epithelial cells, mesangial cells and podocytes. The kidney's vital filtration function depends on the structural integrity of the glomerulus, the proximal portion of the nephron. Within the glomerulus, the architecturally actin-based cytoskeleton podocyte forms the final cellular barrier to filtration. The glomerulus appears as a highly dynamic signalling hub that is capable of integrating intracellular cues from its individual structural components. Dynamic regulation of the podocyte cytoskeleton is required for efficient barrier function of the kidney. As master regulators of actin cytoskeletal dynamics, Rho GTPases are therefore of critical importance for sustained kidney barrier function. Dysregulated activities of the Rho GTPases and of their effectors are implicated in the pathogenesis of both hereditary and idiopathic forms of kidney diseases. Diabetic nephropathy is a progressive kidney disease that is caused by injury to kidney glomeruli. High glucose activates RhoA/Rho-kinase in mesangial cells, leading to excessive extracellular matrix production (glomerulosclerosis). This RhoA/Rho-kinase pathway also seems involved in the post-transplant hypertension frequently observed during treatment with calcineurin inhibitors, whereas Rac1 activation was observed in post-transplant ischaemic acute kidney injury.

Lysine Acetylation in the Proteome of Renal Tubular Epithelial Cells in Diabetic Nephropathy

Diabetic nephropathy is considered one of the most common microvascular complications of diabetes and the pathophysiology involves multiple factors. Progressive diabetic nephropathy is believed to be related to the structure and function of the tubular epithelial cells in the kidney. However, the role of lysine acetylation in lesions of the renal tubular epithelial cells arising from hyperglycemia is poorly understood. Consequently, in this study, we cultured mouse renal tubular epithelial cells in vitro under high glucose conditions and analyzed the acetylation levels of proteins by liquid chromatography-high-resolution mass spectrometry. We identified 48 upregulated proteins and downregulated 86 proteins. In addition, we identified 113 sites with higher acetylation levels and 374 sites with lower acetylation levels. Subcellular localization analysis showed that the majority of the acetylated proteins were located in the mitochondria (43.17%), nucleus (28.57%) and cytoplasm (16.19%). Enrichment analysis indicated that these acetylated proteins are primarily associated with oxidative phosphorylation, the citrate cycle (TCA cycle), metabolic pathways and carbon metabolism. In addition, we used the MCODE plug-in and the cytoHubba plug-in in Cytoscape software to analyze the PPI network and displayed the first four most compact MOCDEs and the top 10 hub genes from the differentially expressed proteins between global and acetylated proteomes. Finally, we extracted 37 conserved motifs from 4915 acetylated peptides. Collectively, this comprehensive analysis of the proteome reveals novel insights into the role of lysine acetylation in tubular epithelial cells and may make a valuable contribution towards the identification of the pathological mechanisms of diabetic nephropathy.

Intranasal immunization with a vaccinia virus vaccine vector expressing pre-fusion stabilized SARS-CoV-2 spike fully protected mice against lethal challenge with the heavily mutated mouse-adapted SARS2-N501Y MA30 strain of SARS-CoV-2

The Omicron SARS-CoV-2 variant has been designated a variant of concern because its spike protein is heavily mutated. In particular, Omicron spike is mutated at 5 positions (K417, N440, E484, Q493 and N501) that have been associated with escape from neutralizing antibodies induced by either infection with or immunization against the early Washington strain of SARS-CoV-2. The mouse-adapted strain of SARS-CoV-2, SARS2-N501Y _MA30 , contains a spike that is also heavily mutated, with mutations at 4 of the 5 positions in Omicron spike associated with neutralizing antibody escape (K417, E484, Q493 and N501). In this manuscript we show that intranasal immunization with a pre-fusion stabilized Washington strain spike, expressed from a highly attenuated, replication-competent vaccinia virus construct, NYVAC-KC, fully protected mice against disease and death from SARS2-N501Y _MA30 . Similarly, immunization by scarification on the skin fully protected against death, but not from mild disease. This data demonstrates that Washington strain spike, when expressed from a highly attenuated, replication-competent poxvirus, administered without parenteral injection can fully protect against the heavily mutated mouse-adapted SARS2-N501Y _MA30 .

Regulation of transforming growth factor-β signalling by SUMOylation and its role in fibrosis

Fibrosis is an abnormal healing process that only repairs the structure of an organ after injury and does not address damaged functions. The pathogenesis of fibrosis is multifactorial and highly complex; numerous signalling pathways are involved in this process, with the transforming growth factor-β (TGF-β) signalling pathway playing a central role. TGF-β regulates the generation of myofibroblasts and the epithelial-mesenchymal transition by regulating transcription and translation of downstream genes and precisely regulating fibrogenesis. The TGF-β signalling pathway can be modulated by various post-translational modifications, of which SUMOylation has been shown to play a key role. In this review, we focus on the function of SUMOylation in canonical and non-canonical TGF-β signalling and its role in fibrosis, providing promising therapeutic strategies for fibrosis.

Study on the Effect of Combination of Prednisone and Vitamin D in the Treatment of Primary Nephrotic Syndrome in Children

Objective

To study the effect of prednisone combined with vitamin D in the treatment of primary nephrotic syndrome in children.

Method

73 cases of primary nephrotic syndrome admitted to the nephrology department of our hospital were randomly selected and retrospectively analyzed. 36 cases were treated with prednisone as the control group, and 37 cases were treated with prednisone combined with vitamin D as the observation group. The efficacy was compared after 3 months of continuous treatment.

Result

After 3 months of treatment, the blood calcium of the observation group was higher than that of the control group, PTH was lower than that of the control group, and 25-(OH)2D3 and 1,25-(OH)2D3 were higher than those of the control group (P < 0.05). After 1, 2, and 3 months of treatment in the observation group, Scr and 24-h urine protein quantification were lower than those in the control group and eGFR was higher than that in the control group (P < 0.05). CD4+ and CD4+/CD8+ were lower in the observation group than in the control group after 3 months of treatment (P < 0.05). The serum sTfR and TGF-β1 levels were lower in the observation group than in the control group after 3 months of treatment (P < 0.05). The total effective rate of the observation group was 83.78% after 3 months of combined treatment with prednisone and vitamin D, which was significantly higher than the total effective rate of the control group of 61.11% (P < 0.05). The incidence of nausea and vomiting, heartburn, headache, dry cough, hypercalcemia, and constipation during treatment in the observation group was not statistically different from that in the control group (P > 0.05).

Conclusion

Combined treatment of primary nephrotic syndrome in children with prednisone and vitamin D can more significantly improve the level of clinical indicators, improve renal function and immune function, and obtain more satisfactory efficacy, without significantly affecting the safety of treatment.

The intersection of Mineralocorticoid Receptor (MR) activation and the FGF23 - Klotho cascade. A Duopoly that promotes renal and cardiovascular injury

The nexus of CKD and cardiovascular disease (CVD) amplifies the morbidity and mortality of CKD, emphasizing the need for defining and establishing therapeutic initiatives to modify and abrogate the progression of CKD and concomitant CV risks. In addition to the traditional CV risk factors, disturbances of mineral metabolism are specific risk factors that contribute to the excessive CV mortality in patients with CKD. These risk factors include dysregulations of circulating factors that modulate phosphate metabolism including fibroblast growth factor 23 (FGF23) and soluble Klotho. Reduced circulating levels and suppressed renal klotho expression may be associated with adverse outcomes in CKD patients. While elevated circulating concentrations or locally produced FGF23 in the strained heart exert pro-hypertrophic mechanisms on the myocardium, Klotho attenuates tissue fibrosis, progression of CKD, cardiomyopathy, endothelial dysfunction, vascular stiffness, and vascular calcification. Mineralocorticoid receptor (MR) activation in non-classical targets, mediated by aldosterone and other ligands, amplifies CVD in CKD. In concert, we detail how the interplay of elevated FGF23, activation of the MR, and concomitant reductions of circulating Klotho in CKD, may potentiate each other's deleterious effects on kidney and the heart, thereby contributing to the initiation and progression of kidney and cardiac functional deterioration, acting through multipronged albeit complementary mechanistic pathways.

Negative regulators of TGF-β1 signaling in renal fibrosis; pathological mechanisms and novel therapeutic opportunities

Elevated expression of the multifunctional cytokine transforming growth factor β1 (TGF-β1) is causatively linked to kidney fibrosis progression initiated by diabetic, hypertensive, obstructive, ischemic and toxin-induced injury. Therapeutically relevant approaches to directly target the TGF-β1 pathway (e.g., neutralizing antibodies against TGF-β1), however, remain elusive in humans. TGF-β1 signaling is subjected to extensive negative control at the level of TGF-β1 receptor, SMAD2/3 activation, complex assembly and promoter engagement due to its critical role in tissue homeostasis and numerous pathologies. Progressive kidney injury is accompanied by the deregulation (loss or gain of expression) of several negative regulators of the TGF-β1 signaling cascade by mechanisms involving protein and mRNA stability or epigenetic silencing, further amplifying TGF-β1/SMAD3 signaling and fibrosis. Expression of bone morphogenetic proteins 6 and 7 (BMP6/7), SMAD7, Sloan-Kettering Institute proto-oncogene (Ski) and Ski-related novel gene (SnoN), phosphate tensin homolog on chromosome 10 (PTEN), protein phosphatase magnesium/manganese dependent 1A (PPM1A) and Klotho are dramatically decreased in various nephropathies in animals and humans albeit with different kinetics while the expression of Smurf1/2 E3 ligases are increased. Such deregulations frequently initiate maladaptive renal repair including renal epithelial cell dedifferentiation and growth arrest, fibrotic factor (connective tissue growth factor (CTGF/CCN2), plasminogen activator inhibitor type-1 (PAI-1), TGF-β1) synthesis/secretion, fibroproliferative responses and inflammation. This review addresses how loss of these negative regulators of TGF-β1 pathway exacerbates renal lesion formation and discusses the therapeutic value in restoring the expression of these molecules in ameliorating fibrosis, thus, presenting novel approaches to suppress TGF-β1 hyperactivation during chronic kidney disease (CKD) progression.

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

Truncated transforming growth factor-β receptor type II (tTβRII) is a promising anti-fibrotic candidate because it attenuates excessive transforming growth factor-β1 (TGF-β1) and then blocks TGF-β1 activity in hepatic fibrosis. However, its use has been greatly limited due to the fact that it is expensive to chemically synthesize and it does not specifically target to the lesion site. In this study, we describe that platelet- derived growth factor β receptor (PDGFβR)-binding peptide BiPPB modified tTβRII (BiPPB-tTβRII) was prepared from the cleavage of SUMO-BiPPB-tTβRII by digestion with SUMO-specific protease. Moreover, compared to the unmodified tTβRII, the target protein BiPPB-tTβRII not only highly specific targeted activated hepatic stellate cells (HSCs) and fibrotic liver tissue, but also significantly inhibited the protein levels of fibrosis-related genes in TGF-β1-induced HSC-T6 cells and CCl₄-induced liver fibrosis in mice. Furthermore, BiPPB-tTβRII markedly ameliorated liver morphology, fibrotic responses and the damage of liver function in fibrosis animal. More importantly, BiPPB-tTβRII showed a much lesser extent in binding to quiescent HSCs and non-fibrotic liver tissue. Taken together, our results suggested that the target protein BiPPB-tTβRII, with its high specific fibrotic liver-targeting potential and its improved anti-fibrotic activity in liver fibrosis, may be a potential therapeutic agent for liver fibrosis.

P-Rex1 Cooperates With TGFβR2 to Drive Lung Fibroblast Migration in Pulmonary Fibrosis

Pulmonary fibrosis is a kind of interstitial lung disease with progressive pulmonary scar formation, leading to irreversible loss of lung functions. The TGF-β1/Smad signaling pathway plays a key role in fibrogenic processes. It is associated with the increased synthesis of extracellular matrix, enhanced proliferation of fibroblasts, and transformation of alveolar epithelial cells into interstitial cells. We investigated P-Rex1, a PIP₃-Gβγ-dependent guanine nucleotide exchange factor (GEF) for Rac, for its potential role in TGF-β1-induced pulmonary fibrosis. A high expression level of P-Rex1 was identified in the lung tissue of patients with pulmonary fibrosis than that from healthy donors. Using the P-Rex1 knockdown and overexpression system, we established a novel player of P-Rex1 in mouse lung fibroblast migration. P-Rex1 contributed to fibrogenic processes in lung fibroblasts by targeting the TGF-β type Ⅱ receptor (TGFβR2). The RNA-seq analysis for expression profiling confirmed the modulation of P-Rex1 in cell migration and the involvement of P-Rex1 in TGF-β1 signaling. These results identified P-Rex1 as a signaling molecule involved in TGF-β1-induced pulmonary fibrosis, suggesting that P-Rex1 may be a potential target for pulmonary fibrosis treatment.

PAI-1 induction during kidney injury promotes fibrotic epithelial dysfunction via deregulation of klotho, p53, and TGF-β1-receptor signaling

Renal fibrosis leads to chronic kidney disease, which affects over 15% of the U.S. population. PAI-1 is highly upregulated in the tubulointerstitial compartment in several common nephropathies and PAI-1 global ablation affords protection from fibrogenesis in mice. The precise contribution of renal tubular PAI-1 induction to disease progression, however, is unknown and surprisingly, appears to be independent of uPA inhibition. Human renal epithelial (HK-2) cells engineered to stably overexpress PAI-1 underwent dedifferentiation (E-cadherin loss, gain of vimentin), G2/M growth arrest (increased p-Histone3, p21), and robust induction of fibronectin, collagen-1, and CCN2. These cells are also susceptible to apoptosis (elevated cleaved caspase-3, annexin-V positivity) compared to vector controls, demonstrating a previously unknown role for PAI-1 in tubular dysfunction. Persistent PAI-1 expression results in a loss of klotho expression, p53 upregulation, and increases in TGF-βRI/II levels and SMAD3 phosphorylation. Ectopic restoration of klotho in PAI-1-transductants attenuated fibrogenesis and reversed the proliferative defects, implicating PAI-1 in klotho loss in renal disease. Genetic suppression of p53 reversed the PA1-1-driven maladaptive repair, moreover, confirming a pathogenic role for p53 upregulation in this context and uncovering a novel role for PAI-1 in promoting renal p53 signaling. TGF-βRI inhibition also attenuated PAI-1-initiated epithelial dysfunction, independent of TGF-β1 ligand synthesis. Thus, PAI-1 promotes tubular dysfunction via klotho reduction, p53 upregulation, and activation of the TGF-βRI-SMAD3 axis. Since klotho is an upstream regulator of both PAI-1-mediated p53 induction and SMAD3 signaling, targeting tubular PAI-1 expression may provide a novel, multi-level approach to the therapy of CKD.

The Genomic Response to TGF-β1 Dictates Failed Repair and Progression of Fibrotic Disease in the Obstructed Kidney

Tubulointerstitial fibrosis is a common and diagnostic hallmark of a spectrum of chronic renal disorders. While the etiology varies as to the causative nature of the underlying pathology, persistent TGF-β1 signaling drives the relentless progression of renal fibrotic disease. TGF-β1 orchestrates the multifaceted program of kidney fibrogenesis involving proximal tubular dysfunction, failed epithelial recovery or re-differentiation, capillary collapse and subsequent interstitial fibrosis eventually leading to chronic and ultimately end-stage disease. An increasing complement of non-canonical elements function as co-factors in TGF-β1 signaling. p53 is a particularly prominent transcriptional co-regulator of several TGF-β1 fibrotic-response genes by complexing with TGF-β1 receptor-activated SMADs. This cooperative p53/TGF-β1 genomic cluster includes genes involved in cellular proliferative control, survival, apoptosis, senescence, and ECM remodeling. While the molecular basis for this co-dependency remains to be determined, a subset of TGF-β1-regulated genes possess both p53- and SMAD-binding motifs. Increases in p53 expression and phosphorylation, moreover, are evident in various forms of renal injury as well as kidney allograft rejection. Targeted reduction of p53 levels by pharmacologic and genetic approaches attenuates expression of the involved genes and mitigates the fibrotic response confirming a key role for p53 in renal disorders. This review focuses on mechanisms underlying TGF-β1-induced renal fibrosis largely in the context of ureteral obstruction, which mimics the pathophysiology of pediatric unilateral ureteropelvic junction obstruction, and the role of p53 as a transcriptional regulator within the TGF-β1 repertoire of fibrosis-promoting genes.

MRTF: Basic Biology and Role in Kidney Disease

A lesser known but crucially important downstream effect of Rho family GTPases is the regulation of gene expression. This major role is mediated via the cytoskeleton, the organization of which dictates the nucleocytoplasmic shuttling of a set of transcription factors. Central among these is myocardin-related transcription factor (MRTF), which upon actin polymerization translocates to the nucleus and binds to its cognate partner, serum response factor (SRF). The MRTF/SRF complex then drives a large cohort of genes involved in cytoskeleton remodeling, contractility, extracellular matrix organization and many other processes. Accordingly, MRTF, activated by a variety of mechanical and chemical stimuli, affects a plethora of functions with physiological and pathological relevance. These include cell motility, development, metabolism and thus metastasis formation, inflammatory responses and—predominantly-organ fibrosis. The aim of this review is twofold: to provide an up-to-date summary about the basic biology and regulation of this versatile transcriptional coactivator; and to highlight its principal involvement in the pathobiology of kidney disease. Acting through both direct transcriptional and epigenetic mechanisms, MRTF plays a key (yet not fully appreciated) role in the induction of a profibrotic epithelial phenotype (PEP) as well as in fibroblast-myofibroblast transition, prime pathomechanisms in chronic kidney disease and renal fibrosis.

TGF-β1 Signaling: Immune Dynamics of Chronic Kidney Diseases

Chronic kidney disease (CKD) is a major cause of morbidity and mortality worldwide, imposing a great burden on the healthcare system. Regrettably, effective CKD therapeutic strategies are yet available due to their elusive pathogenic mechanisms. CKD is featured by progressive inflammation and fibrosis associated with immune cell dysfunction, leading to the formation of an inflammatory microenvironment, which ultimately exacerbating renal fibrosis. Transforming growth factor β1 (TGF-β1) is an indispensable immunoregulator promoting CKD progression by controlling the activation, proliferation, and apoptosis of immunocytes via both canonical and non-canonical pathways. More importantly, recent studies have uncovered a new mechanism of TGF-β1 for de novo generation of myofibroblast via macrophage-myofibroblast transition (MMT). This review will update the versatile roles of TGF-β signaling in the dynamics of renal immunity, a better understanding may facilitate the discovery of novel therapeutic strategies against CKD.

Actin Cytoskeleton and Regulation of TGFβ Signaling: Exploring Their Links

Human tissues, to maintain their architecture and function, respond to injuries by activating intricate biochemical and physical mechanisms that regulates intercellular communication crucial in maintaining tissue homeostasis. Coordination of the communication occurs through the activity of different actin cytoskeletal regulators, physically connected to extracellular matrix through integrins, generating a platform of biochemical and biomechanical signaling that is deregulated in cancer. Among the major pathways, a controller of cellular functions is the cytokine transforming growth factor β (TGFβ), which remains a complex and central signaling network still to be interpreted and explained in cancer progression. Here, we discuss the link between actin dynamics and TGFβ signaling with the aim of exploring their aberrant interaction in cancer.

The Small GTPase RAC1B: A Potent Negative Regulator of-and Useful Tool to Study-TGFβ Signaling

RAC1 and its alternatively spliced isoform, RAC1B, are members of the Rho family of GTPases. Both isoforms are involved in the regulation of actin cytoskeleton remodeling, cell motility, cell proliferation, and epithelial-mesenchymal transition (EMT). Compared to RAC1, RAC1B exhibits a number of distinctive features with respect to tissue distribution, downstream signaling and a role in disease conditions like inflammation and cancer. The subcellular locations and interaction partners of RAC1 and RAC1B vary depending on their activation state, which makes RAC1 and RAC1B ideal candidates to establish cross-talk with cancer-associated signaling pathways-for instance, interactions with signaling by transforming growth factor β (TGFβ), a known tumor promoter. Although RAC1 has been found to promote TGFβ-driven tumor progression, recent observations in pancreatic carcinoma cells surprisingly revealed that RAC1B confers anti-oncogenic properties, i.e., through inhibiting TGFβ-induced EMT. Since then, an unexpected array of mechanisms through which RAC1B cross-talks with TGFβ signaling has been demonstrated. However, rather than being uniformly inhibitory, RAC1B interacts with TGFβ signaling in a way that results in the selective blockade of tumor-promoting pathways, while concomitantly allowing tumor-suppressive pathways to proceed. In this review article, we are going to discuss the specific interactions between RAC1B and TGFβ signaling, which occur at multiple levels and include various components such as ligands, receptors, cytosolic mediators, transcription factors, and extracellular inhibitors of TGFβ ligands.

Tubular HIPK2 is a key contributor to renal fibrosis

We previously used global Hipk2-null mice in various models of kidney disease to demonstrate the central role of homeodomain-interacting protein kinase 2 (HIPK2) in renal fibrosis development. However, renal tubular epithelial cell–specific (RTEC-specific) HIPK2 function in renal fibrogenesis has yet to be determined. Here, we show that modulation of tubular HIPK2 expression and activity affects renal fibrosis development in vivo. The loss of HIPK2 expression in RTECs resulted in a marked diminution of renal fibrosis in unilateral ureteral obstruction (UUO) mouse models and HIV-associated nephropathy (HIVAN) mouse models, which was associated with the reduction of Smad3 activation and downstream expression of profibrotic markers. Conversely, WT HIPK2 overexpression in RTECs accentuated the extent of renal fibrosis in the setting of UUO, HIVAN, and folic acid–induced nephropathy in mice. Notably, kinase-dead HIPK2 mutant overexpression or administration of BT173, an allosteric inhibitor of HIPK2-Smad3 interaction, markedly attenuated the renal fibrosis in these mouse models of kidney disease, indicating that HIPK2 requires both the kinase activity and its interaction with Smad3 to promote TGF-β–mediated renal fibrosis. Together, these results establish an important RTEC-specific role of HIPK2 in kidney fibrosis and further substantiate the inhibition of HIPK2 as a therapeutic approach against renal fibrosis.

Modulation of HIPK2 expression in murine renal tubular epithelial cells reveals an important role in renal fibrosis development.

Caveolin1 and YAP drive mechanically induced mesothelial to mesenchymal transition and fibrosis

Despite their emerging relevance to fully understand disease pathogenesis, we have as yet a poor understanding as to how biomechanical signals are integrated with specific biochemical pathways to determine cell behaviour. Mesothelial-to-mesenchymal transition (MMT) markers colocalized with TGF-β1-dependent signaling and yes-associated protein (YAP) activation across biopsies from different pathologies exhibiting peritoneal fibrosis, supporting mechanotransduction as a central driving component of these class of fibrotic lesions and its crosstalk with specific signaling pathways. Transcriptome and proteome profiling of the response of mesothelial cells (MCs) to linear cyclic stretch revealed molecular changes compatible with bona fide MMT, which (i) overlapped with established YAP target gene subsets, and were largely dependent on endogenous TGF-β1 signaling. Importantly, TGF-β1 blockade blunts the transcriptional upregulation of these gene signatures, but not the mechanical activation and nuclear translocation of YAP per se. We studied the role therein of caveolin-1 (CAV1), a plasma membrane mechanotransducer. Exposure of CAV1-deficient MCs to cyclic stretch led to a robust upregulation of MMT-related gene programs, which was blunted upon TGF-β1 inhibition. Conversely, CAV1 depletion enhanced both TGF-β1 and TGFBRI expression, whereas its re-expression blunted mechanical stretching-induced MMT. CAV1 genetic deficiency exacerbated MMT and adhesion formation in an experimental murine model of peritoneal ischaemic buttons. Taken together, these results support that CAV1-YAP/TAZ fine-tune the fibrotic response through the modulation of MMT, onto which TGF-β1-dependent signaling coordinately converges. Our findings reveal a cooperation between biomechanical and biochemical signals in the triggering of MMT, representing a novel potential opportunity to intervene mechanically induced disorders coursing with peritoneal fibrosis, such as post-surgical adhesions.

Transient Receptor Potential Vanilloid channel regulates fibroblast differentiation and airway remodeling by modulating redox signals through NADPH Oxidase 4

Asthma is characterized by pathological airway remodeling resulting from persistent myofibroblast activation. Although transforming growth factor beta 1 (TGFβ1), mechanical signals, and reactive oxygen species (ROS) are implicated in fibroblast differentiation, their integration is still elusive. We identified that Transient Receptor Potential Vanilloid 4 (TRPV4), a mechanosensitive ion channel mediates lung fibroblast (LF) differentiation and D. farinae-induced airway remodeling via a novel TRPV4-NADPH Oxidase 4 (NOX4) interaction. NOX4-mediated ROS production is essential for TGFβ1-induced LF differentiation via myocardin-related transcription factor-A (MRTF-A) and plasminogen activator inhibitor 1 (PAI-1). Importantly, TRPV4 inhibition prevented TGFβ1-induced NOX4 expression and ROS production. Both TRPV4 and NOX4 are activated by phosphatidylinositol 3-kinase (PI3K) downstream of TGFβ1, and signals from both TRPV4 and Rac are necessary for NOX4 upregulation. Notably, NOX4 expression is higher in fibroblasts derived from asthmatic patients (disease human LF; DHLF) in comparison to non-asthmatics (normal human LF; NHLF). Further, NOX4 expression is up-regulated in the lungs of D.farinae-treated wild type mice (WT) relative to saline-treated WT, which was attenuated in TRPV4 knockout (KO) mice. Our findings suggest that TRPV4 integrates TGFβ1 and ROS signaling through NOX4 and, TRPV4-NOX4 interaction is amenable to target lung remodeling during asthma.

The Crosstalk between Src and Hippo/YAP Signaling Pathways in Non-Small Cell Lung Cancer (NSCLC)

The advancement of new therapies, including targeted therapies and immunotherapies, has improved the survival of non-small-cell lung cancer (NSCLC) patients in the last decade. Some NSCLC patients still do not benefit from therapies or encounter progressive disease during the course of treatment because they have intrinsic resistance, acquired resistance, or lack a targetable driver mutation. More investigations on the molecular biology of NSCLC are needed to find useful biomarkers for current therapies and to develop novel therapeutic strategies. Src is a non-receptor tyrosine kinase protein that interacts with cell surface growth factor receptors and the intracellular signaling pathway to maintain cell survival tumorigenesis in NSCLC. The Yes-associated protein (YAP) is one of the main effectors of the Hippo pathway and has been identified as a promoter of drug resistance, cancer progression, and metastasis in NSCLC. Here, we review studies that have investigated the activation of YAP as mediated by Src kinases and demonstrate that Src regulates YAP through three main mechanisms: (1) direct phosphorylation; (2) the activation of pathways repressing Hippo kinases; and (3) Hippo-independent mechanisms. Further work should focus on the efficacy of Src inhibitors in inhibiting YAP activity in NSCLC. In addition, future efforts toward developing potentially reasonable combinations of therapy targeting the Src–YAP axis using other therapies, including targeted therapies and/or immunotherapies, are warranted.