PI3K/AKT activation attenuates acute kidney injury following liver transplantation by inducing FoxO3a nuclear export and deacetylation

The Role of MicroRNA in the Pathogenesis of Acute Kidney Injury

Acute kidney injury (AKI) describes a condition associated with elevated serum creatinine levels and decreased glomerular filtration rate. AKI can develop as a result of sepsis, the nephrotoxic properties of several drugs, and ischemia/reperfusion injury. Renal damage can be associated with metabolic acidosis, fluid overload, and ionic disorders. As the molecular background of the pathogenesis of AKI is insufficiently understood, more studies are needed to identify the key signaling pathways and molecules involved in the progression of AKI. Consequently, future treatment methods may be able to restore organ function more rapidly and prevent progression to chronic kidney disease. MicroRNAs (miRNAs) are small molecules that belong to the non-coding RNA family. Recently, numerous studies have demonstrated the altered expression profile of miRNAs in various diseases, including inflammatory and neoplastic conditions. As miRNAs are major regulators of gene expression, their dysregulation is associated with impaired homeostasis and cellular behavior. The aim of this article is to discuss current evidence on the involvement of miRNAs in the pathogenesis of AKI.

PTEN in kidney diseases: a potential therapeutic target in preventing AKI-to-CKD transition

Renal fibrosis, a critical factor in the development of chronic kidney disease (CKD), is predominantly initiated by acute kidney injury (AKI) and subsequent maladaptive repair resulting from pharmacological or pathological stimuli. Phosphatase and tensin homolog (PTEN), also known as phosphatase and tensin-associated phosphatase, plays a pivotal role in regulating the physiological behavior of renal tubular epithelial cells, glomeruli, and renal interstitial cells, thereby preserving the homeostasis of renal structure and function. It significantly impacts cell proliferation, apoptosis, fibrosis, and mitochondrial energy metabolism during AKI-to-CKD transition. Despite gradual elucidation of PTEN's involvement in various kidney injuries, its specific role in AKI and maladaptive repair after injury remains unclear. This review endeavors to delineate the multifaceted role of PTEN in renal pathology during AKI and CKD progression along with its underlying mechanisms, emphasizing its influence on oxidative stress, autophagy, non-coding RNA-mediated recruitment and activation of immune cells as well as renal fibrosis. Furthermore, we summarize prospective therapeutic targeting strategies for AKI and CKD-treatment related diseases through modulation of PTEN.

The role of PI3K/Akt signaling pathway in chronic kidney disease

Chronic kidney disease (CKD), including chronic glomerulonephritis, IgA nephropathy and diabetic nephropathy, are common chronic diseases characterized by structural damage and functional decline of the kidneys. The current treatment of CKD is symptom relief. Several studies have reported that the phosphatidylinositol 3 kinases (PI3K)/protein kinase B (Akt) signaling pathway is a pathway closely related to the pathological process of CKD. It can ameliorate kidney damage by inhibiting this signal pathway which is involved with inflammation, oxidative stress, cell apoptosis, epithelial mesenchymal transformation (EMT) and autophagy. This review highlights the role of activating or inhibiting the PI3K/Akt signaling pathway in CKD-induced inflammatory response, apoptosis, autophagy and EMT. We also summarize the latest evidence on treating CKD by targeting the PI3K/Akt pathway, discuss the shortcomings and deficiencies of PI3K/Akt research in the field of CKD, and identify potential challenges in developing these clinical therapeutic CKD strategies, and provide appropriate solutions.

Dehydroevodiamine ameliorates neurological dysfunction after traumatic brain injury in mice via regulating the SIRT1/FOXO3a/Bim pathway

BACKGROUND

Traumatic Brain Injury (TBI) poses a considerable public health challenge, resulting in mortality, disability, and economic strain. Dehydroevodiamine (DEDM) is a natural compound derived from a traditional Chinese herbal medicine. Prior studies have substantiated the neuroprotective attributes of this compound in the context of TBI. Nevertheless, a comprehensive comprehension of the exact mechanisms responsible for its neuroprotective effects remains elusive. It is imperative to elucidate the precise intrinsic mechanisms underlying the neuroprotective actions of DEDM.

PURPOSE

The aim of this investigation was to elucidate the mechanism underlying DEDM treatment in TBI utilizing both in vivo and in vitro models. Specifically, our focus was on comprehending the impact of DEDM on the Sirtuin1 (SIRT1) / Forkhead box O3 (FOXO3a) / Bcl-2-like protein 11 (Bim) pathway, a pivotal player in TBI-induced cell death attributed to oxidative stress.

STUDY DESIGN AND METHODS

We established a TBI mouse model via the weight drop method. Following continuous intraperitoneal administration, we assessed the neurological dysfunction using the Modified Neurological Severity Score (mNSS) and behavioral assay, followed by sample collection. Secondary brain damage in mice was evaluated through Nissl staining, brain water content measurement, Evans blue detection, and Western blot assays. We scrutinized the expression levels of oxidative stress-related indicators and key proteins for apoptosis. The intricate mechanism of DEDM in TBI was further explored through immunofluorescence, Co-immunoprecipitation (Co-IP) assays, real-time quantitative PCR (RT-qPCR), dual-luciferase assays and western blotting. Additionally, we further investigated the specific therapeutic mechanism of DEDM in an oxidative stress cell model.

RESULTS

The results indicated that DEDM effectively ameliorated oxidative stress and apoptosis post-TBI, mitigating neurological dysfunction and brain injury in mice. DEDM facilitated the deacetylation of FOXO3a by up-regulating the expression of the deacetylase SIRT1, consequently suppressing Bim expression. This mechanism contributed to the alleviation of neurological injury and symptom improvement in TBI-afflicted mice. Remarkably, SIRT1 emerged as a central mediator in the overall treatment mechanism.

CONCLUSIONS

DEDM exerted significant neuroprotective effects on TBI mice by modulating the SIRT1/FOXO3a/Bim pathway. Our innovative research provides a basis for further exploration of the clinical therapeutic potential of DEDM in the context of TBI.

Galectin-9 alleviates acute graft-versus-host disease after haplo-hematopoietic stem cell transplantation by regulating regulatory T cell/effector T cell imbalance

BACKGROUND

Acute graft-versus-host disease (aGVHD) arises from the imbalance of host T cells. Galectin-9 negatively regulates CD4 effector T cell (Th1 and Th17) function by binding to Tim-3. However, the relationship between Galectin-9/Tim-3 and CD4+ T subsets in patients with aGVHD after Haplo-HSCT (haploidentical peripheral blood hematopoietic stem cell transplantation) has not been fully elucidated. Here, we investigated the role of Galectin-9 and CD4+ T subsets in aGVHD after haplo-HSCT.

METHODS

Forty-two patients underwent Haplo-HSCT (26 without aGVHD and 16 with aGVHD), and 20 healthy controls were included. The concentrations of Galectin-9, interferon-gamma (IFN-γ), interleukin (IL)-4, transforming growth factor (TGF)-β, and IL-17 in the serum and culture supernatant were measured using enzyme-linked immunosorbent assay or cytometric bead array. The expression levels of Galectin-9, PI3K, p-PI3K, and p-mTOR protein were detected by western blot analysis. Flow cytometry was used to analyze the proportions of CD4+ T cell subsets. Bioinformatics analysis was performed.

RESULTS

In patients with aGVHD, regulatory T (Treg) cells and Galectin-9 decreased, and the Th1, Th17, and Treg cells were significantly imbalanced. Moreover, Treg and Galectin-9 were rapidly reconstituted in the early stage of patients without aGVHD after Haplo-HSCT, but Th17 cells were reconstituted slowly. Furthermore, Tim-3 upregulation on Th17 and Th1 cells was associated with excessive activation of the PI3K/AKT pathway in patients with aGVHD. Specifically, in vitro treatment with Galectin-9 reduced IFN-γ and IL-17 production while augmenting TGF-β secretion. Bioinformatics analysis suggested the potential involvement of the PI3K/AKT/mTOR pathway in aGVHD. Mechanistically, exogenous Galectin-9 was found to mitigate aGVHD by restoring the Treg/Teffs (effector T cells) balance and suppressing PI3K.

CONCLUSION

Galectin-9 may ameliorate aGVHD after haplo-HSCT by modulating Treg/Teffs balance and regulating the PI3K/AKT/mTOR pathway. Targeting Galectin-9 may hold potential value for the treatment of aGVHD.

Downregulating miR-184 relieves calcium oxalate crystal-mediated renal cell damage via activating the Rap1 signaling pathway

BACKGROUND

Renal calculi are a very prevalent disease with a high incidence. Calcium oxalate (CaOx) is a primary constituent of kidney stones. Our paper probes the regulatory function and mechanism of miR-184 in CaOx-mediated renal cell damage.

METHODS

CaOx was used to treat HK2 cells and human podocytes (HPCs) to simulate kidney cell damage. The qRT-PCR technique checked the profiles of miR-184 and IGF1R. The examination of cell proliferation was conducted employing CCK8. TUNEL staining was used to monitor cell apoptosis. Western blot analysis was used to determine the protein profiles of apoptosis-concerned related proteins (including Mcl1, Bcl-XL, and Caspase-3), the NF-κB, Nrf2/HO-1, and Rap1 signaling pathways. ELISA confirmed the levels of the inflammatory factors IL-6, TNF-α, MCP1, and ICAM1. The targeting relationship between miR-184 and IGF1R was validated by dual luciferase assay and RNA immunoprecipitation assay.

RESULTS

Glyoxylate-induced rat kidney stones model and HK2 and HPC cells treated with CaOx demonstrated an increase in the miR-184 profile. Inhibiting miR-184 relieved CaOx-mediated renal cell inflammation, apoptosis and oxidative stress and activated the Rap1 pathway. IGF1R was targeted by miR-184. IGF1R activation by IGF1 attenuated the effects of miR-184 on renal cell damage, and Hippo pathway suppression reversed the inhibitory effect of miR-184 knockdown on renal cell impairment.

CONCLUSIONS

miR-184 downregulation activates the Rap1 signaling pathway to ameliorate renal cell damage mediated by CaOx.

5-methoxytryptophan induced apoptosis and PI3K/Akt/FoxO3a phosphorylation in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a highly prevalent malignancy worldwide, and new therapeutic targets urgently need to be found to prolong patient survival. 5-methoxytryptophan (5-MTP) is a tryptophan metabolite found in animals and humans. However, the effects of 5-MTP on proliferation and apoptosis of CRC cells are currently unknown.

AIM

To investigate the effects of 5-MTP on the proliferation, migration, invasion, and apoptosis abilities of CRC cells. Additionally, we seek to explore whether 5-MTP has the potential to be utilized as a drug for the treatment of CRC.

METHODS

In order to evaluate the effect of 5-MTP on CRC cells, a series of experiments were conducted for evaluation. Colony formation assay and Cell Counting Kit 8 assays were used to investigate the impact of 5-MTP on the proliferation of CRC cell lines. Cell cycle assays were employed to examine the effect of 5-MTP on cellular growth. In addition, we investigated the effects of 5-MTP on apoptosis and reactive oxygen species in HCT-116 cells. To obtain a deeper understanding of how 5-MTP affects CRC, we conducted a study to examine its influence on the PI3K/Akt signaling pathway in CRC cells.

RESULTS

This article showed that 5-MTP promoted apoptosis and cell cycle arrest and inhibited cell proliferation in CRC cells. In many articles, it has been reported that PI3K/Akt/FoxO3a signaling pathway is one of the most important signaling pathways involved in internal regulating cell proliferation and differentiation. Nevertheless, 5-MTP combined with PI3K/Akt/FoxO3a signaling pathway inhibitors significantly promoted apoptosis and cell cycle arrest and inhibited cell proliferation in CRC cells compared with 5-MTP alone in our study.

CONCLUSION

Therefore, there is strong evidence that 5-MTP can be used as an effective medicine for CRC treatment.

Skimmianine attenuates liver ischemia/reperfusion injury by regulating PI3K-AKT signaling pathway-mediated inflammation, apoptosis and oxidative stress

Liver ischemia/reperfusion (I/R) injury is a common injury after liver transplantation and hepatectomy. Skimmianine (Ski) has antibacterial, antiviral pharmacological effects. However, it is not clear whether Ski has a protective effect against liver I/R injury. In the present study, we established a mouse liver I/R model and an AML12 cell hypoxia-reoxygenation (H/R) model, both pretreated with different concentrations of Ski. Serum transaminase levels, necrotic liver area, cell viability, inflammatory factors, oxidative stress and apoptosis-related levels were measured to assess the protective effect of Ski against liver I/R injury. Western blotting was used to detect apoptosis-related proteins and PI3K-AKT pathway-related proteins. Mice and cells were also treated with PI3K inhibitor LY294002 to assess changes in indicators of liver injury. The results showed that Ski significantly reduced transaminase levels, liver necrosis area, oxidative stress, and apoptosis levels in mice with I/R. Ski also inhibited cell injury and apoptosis after H/R. Moreover, Ski activated phosphorylation of PI3K-AKT pathway-related proteins after liver I/R and cell H/R. Importantly, the PI3K inhibitor LY294002 effectively reversed the alleviation of I/R injury caused by Ski. These results confirm that Ski exerts a protective effect against liver I/R injury through activation of the PI3K-AKT pathway.

Aerobic exercise enhances mitochondrial homeostasis to counteract D-galactose-induced sarcopenia in zebrafish

Sarcopenia is a common skeletal muscle degenerative disease characterized by decreased skeletal muscle mass and mitochondrial dysfunction that involves microRNAs (miR) as regulatory factors in various pathways. Exercise reduces age-related oxidative damage and chronic inflammation and increases autophagy, among others. Moreover, whether aerobic exercise can regulate mitochondrial homeostasis by modulating the miR-128/insulin-like growth factor-1 (IGF-1) signaling pathway and can improve sarcopenia requires further investigation. Interestingly, zebrafish have been used as a model for aging research for over a decade due to their many outstanding advantages. Therefore, we established a model of zebrafish sarcopenia using d-galactose immersion and observed substantial changes, including reduced skeletal muscle cross-sectional area, increased tissue fibrosis, decreased motility, increased skeletal muscle reactive oxygen species, and notable alterations in mitochondrial morphology and function. We found that miR-128 expression was considerably upregulated, where as Igf1 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha were significantly downregulated; moreover, mitochondrial homeostasis was reduced. Four weeks of aerobic exercise delayed sarcopenia progression and prevented the disruption of mitochondrial function and homeostasis. The genes related to atrophy and miR-128 were downregulated, Igf1 expression was considerably upregulated, and the phosphorylation levels of Pi3k, Akt, and Foxo3a were upregulated. Furthermore, mitochondrial respiration and homeostasis were enhanced. In conclusion, aerobic exercise improved skeletal muscle quality and function via the miR-128/IGF-1 signaling pathway, consequently ameliorating mitochondrial homeostasis in aging skeletal muscle.

The rules and regulatory mechanisms of FOXO3 on inflammation, metabolism, cell death and aging in hosts

The FOX family of transcription factors was originally identified in 1989, comprising the FOXA to FOXS subfamilies. FOXO3, a well-known member of the FOXO subfamily, is widely expressed in various human organs and tissues, with higher expression levels in the ovary, skeletal muscle, heart, and spleen. The biological effects of FOXO3 are mostly determined by its phosphorylation, which occurs in the nucleus or cytoplasm. Phosphorylation of FOXO3 in the nucleus can promote its translocation into the cytoplasm and inhibit its transcriptional activity. In contrast, phosphorylation of FOXO3 in the cytoplasm leads to its translocation into the nucleus and exerts regulatory effects on biological processes, such as inflammation, aerobic glycolysis, autophagy, apoptosis, oxidative stress, cell cycle arrest and DNA damage repair. Additionally, FOXO3 isoform 2 acts as an important suppressor of osteoclast differentiation. FOXO3 can also interfere with the development of various diseases, including inhibiting the proliferation and invasion of tumor cells, blocking the production of inflammatory factors in autoimmune diseases, and inhibiting β-amyloid deposition in Alzheimer's disease. Furthermore, FOXO3 slows down the aging process and exerts anti-aging effects by delaying telomere attrition, promoting cell self-renewal, and maintaining genomic stability. This review suggests that changes in the levels and post-translational modifications of FOXO3 protein can maintain organismal homeostasis and improve age-related diseases, thus counteracting aging. Moreover, this may indicate that alterations in FOXO3 protein levels are also crucial for longevity, offering new perspectives for therapeutic strategies targeting FOXO3.

Jiedu Tongluo Baoshen formula enhances renal tubular epithelial cell autophagy to prevent renal fibrosis by activating SIRT1/LKB1/AMPK pathway

Renal fibrosis, an important pathological change in the development of diabetic kidney disease (DKD), urgently needs new treatment methods clinically. The Jiedu Tongluo Baoshen (JTBF) formula was created based on the theory of toxic damage to the kidney collaterals, and a variety of active ingredients in JTBF have inhibitory effects on epithelial-mesenchymal transition (EMT) and extracellular matrix (ECM). In this study, the Ultra Performance Liquid Chromatography (UPLC) was employed to analyze the effective ingredients in the JTBF formula. After screening in the PubChem database, we identified 94 active compounds of JTBF and predicted the SIRT1 pathway as potential targets through network pharmacology. In addition, in the high fat diet (HFD)+Streptozocin (STZ)-induced DKD rat model and high glucose (HG)-induced NRK-52E cell model, JTBF treatment activates the phosphorylation of LKB1 and AMPK and enhances the autophagy activity of NRK-52E cells, thereby reducing the accumulation of EMT and ECM. These results have been confirmed in vivo and in vitro experiments. JTBF enhances the autophagy activity of renal tubular epithelial cells and inhibits the progression of DKD renal fibrosis by activating the SIRT1/LKB1/AMPK signal pathway. This study provides new insights into the molecular mechanism of JTBF to prevent and treat DKD renal fibrosis.

Urinary single-cell sequencing captures kidney injury and repair processes in human acute kidney injury

Acute kidney injury (AKI) is a major health issue, the outcome of which depends primarily on damage and reparative processes of tubular epithelial cells. Mechanisms underlying AKI remain incompletely understood, specific therapies are lacking and monitoring the course of AKI in clinical routine is confined to measuring urine output and plasma levels of filtration markers. Here we demonstrate feasibility and potential of a novel approach to assess the cellular and molecular dynamics of AKI by establishing a robust urine-to-single cell RNA sequencing (scRNAseq) pipeline for excreted kidney cells via flow cytometry sorting. We analyzed 42,608 single cell transcriptomes of 40 urine samples from 32 patients with AKI and compared our data with reference material from human AKI post-mortem biopsies and published mouse data. We demonstrate that tubular epithelial cells transcriptomes mirror kidney pathology and reflect distinct injury and repair processes, including oxidative stress, inflammation, and tissue rearrangement. We also describe an AKI-specific abundant urinary excretion of adaptive progenitor-like cells. Thus, single cell transcriptomics of kidney cells excreted in urine provides noninvasive, unprecedented insight into cellular processes underlying AKI, thereby opening novel opportunities for target identification, AKI sub-categorization, and monitoring of natural disease course and interventions.

Plasma proteomic characterization of the development of acute kidney injury in early sepsis patients

Acute kidney injury (AKI) develops frequently in the course of patients with sepsis and strongly associates with in-hospital mortality. However, diagnosing AKI involves a considerable lag-time because it depends on assessing an increase in serum creatinine, and offers no insight in the underlying pathophysiology. Consequently, identifying a set of proteins reflecting the development of AKI may improve earlier recognition of AKI and the understanding of its pathophysiology. A targeted plasma proteomic approach was performed in early sepsis patients with and without subsequent AKI development in a matched pair design (n = 19 each). Principal component analysis identified 53 proteins associated with development of AKI, which were further analysed using Enrichr gene ontology and pathway analysis. Nine differentially expressed proteins from the targeted proteomics were increased among patients who subsequently developed AKI and correlated with principal components, namely CALCA, CALR, CA12, CLEC1A, PTK7, KIM-1, NPPC, NUCB2 and PGF. We demonstrated the biological insight in the development of AKI in early sepsis compared to non-AKI sepsis.

LncRNA Snhg1 Plays an Important Role via Sequestering rno-miR-139-5p to Function as a ceRNA in Acute Rejection After Rat Liver Transplantation Based on the Bioinformatics Analysis

In order to explore the molecular mechanism of acute rejection after liver transplantation (ARLT) in rats, we employed the GSE36798 data set in the Gene Expression Omnibust (GEO) database to construct a related ceRNA network. This dataset contained a total of 16 samples (8 graft samples and 8 plasma samples). Each kind of sample was divided into acute rejection (AR) groups and non-acute rejection (NR) groups, and each group had 4 replicates. First, we performed principal component analysis (PCA) with downloaded data to compare the difference between samples in a macroscopic way. Then, we used the “limma” R package to screen out differentially expressed miRNAs among different groups and used the “pheatmap” R package to perform bidirectional hierarchical clustering analysis for these differentially expressed miRNAs. The miRWalk database and the LncBase V.2 database were applied to predict downstream target genes and upstream-related lncRNAs, respectively. Meanwhile, the String database was used to predict the relationship between target genes, and the aforementioned results were processed for visualization by Cytoscape software. In addition, we exhibited the ultimate ceRNA network, including two lncRNAs, two miRNAs, and 77 mRNAs. Finally, we constructed a rat model of ARLT and applied graft specimens to relevant experimental verification. We found that the lncRNA Snhg1/rno-miR-139-5p axis might be involved in the regulation of ARLT in rats. In short, we demonstrated the differentially expressed miRNA profile, constructed a related ceRNA network, and screened out a possible regulatory axis. In view of the conservation of genes among species, this work was expected to provide a new strategy for the treatment and prevention of ARLT in the clinical setting.

Effects of Lycium barbarum glycopeptide on renal and testicular injury induced by di(2-ethylhexyl) phthalate

Di(2-ethylhexyl) phthalate (DEHP) is a common environmental pollutant with renal and reproductive toxicity. Lycium barbarum glycopeptide (LbGp) is the main active component of Lycium barbarum, which can protect the kidney and promote reproduction. Autophagy and apoptosis are the regulatory mechanisms of cell adaptation to external stress. This study investigated whether DEHP and LbGp affect kidney and testis by regulating autophagy and apoptosis. DEHP induced apoptosis in human embryonic kidney-293 (HEK-293) cells and human kidney-2 (HK-2) cells, as well as glomerular enlargement, enhanced renal autophagy and inflammation, decreased testicular germ cells, and enhanced testicular autophagy. LbGp reduced apoptosis in HEK-293 cells and HK-2 cells, reduced glomerular enlargement and renal inflammation, enhanced renal autophagy, increased testicular germ cells, and alleviated testicular autophagy. These results suggested that DEHP induced inflammation to cause kidney injury, mildly enhanced renal autophagy, and also induced excessive autophagy, leading to testicular injury. LbGp reduced inflammation and appropriately enhanced autophagy to alleviate renal injury and also reduced excessive autophagy to alleviate testicular injury. Silent information regulator 1 (SIRT1)/forkhead box O3a (FoxO3a)-mediated autophagy and p38 mitogen-activated protein kinase (p38 MAPK)-mediated inflammation played important roles.

Insights into Growth Factors in Liver Carcinogenesis and Regeneration: An Ongoing Debate on Minimizing Cancer Recurrence after Liver Resection

Hepatocellular carcinoma has become a leading cause of cancer-associated mortality throughout the world, and is of great concern. Currently used chemotherapeutic drugs in the treatment of hepatocellular carcinoma lead to severe side effects, thus underscoring the need for further research to develop novel and safer therapies. Liver resection in cancer patients is routinely performed. After partial resection, liver regeneration is a perfectly calibrated response apparently sensed by the body’s required liver function. This process hinges on the effect of several growth factors, among other molecules. However, dysregulation of growth factor signals also leads to growth signaling autonomy and tumor progression, so control of growth factor expression may prevent tumor progression. This review describes the role of some of the main growth factors whose dysregulation promotes liver tumor progression, and are also key in regenerating the remaining liver following resection. We herein summarize and discuss studies focused on partial hepatectomy and liver carcinogenesis, referring to hepatocyte growth factor, insulin-like growth factor, and epidermal growth factor, as well as their suitability as targets in the treatment of hepatocellular carcinoma. Finally, and given that drugs remain one of the mainstay treatment options in liver carcinogenesis, we have reviewed the current pharmacological approaches approved for clinical use or research targeting these factors.