ABCA1 deficiency-mediated glomerular cholesterol accumulation exacerbates glomerular endothelial injury and dysfunction in diabetic kidney disease

Metal ion formulations for diabetic wound healing: Mechanisms and therapeutic potential

Metals are vital in human physiology, which not only act as enzyme catalysts in the processes of superoxide dismutase and glucose phosphorylation, but also affect the redox process, osmotic adjustment, metabolism and neural signals. However, metal imbalances can lead to diseases such as diabetes, which is marked by chronic hyperglycemia and affects wound healing. The hyperglycemic milieu of diabetes impairs wound healing, posing significant challenges to patient quality of life. Wound healing encompasses a complex cascade of hemostasis, inflammation, proliferation, and remodeling phases, which are susceptible to disruption in hyperglycemic conditions. In recent decades, metals have emerged as critical facilitators of wound repair by enhancing antimicrobial properties (e.g., iron and silver), providing angiogenic stimulation (copper), promoting antioxidant activity and growth factor synthesis (zinc), and supporting wound closure (calcium and magnesium). Consequently, research has pivoted towards the development of metal ion-based therapeutics, including innovative formulations such as nano-hydrogels, nano-microneedle dressings, and microneedle patches. Prepared by combining macromolecular materials such as chitosan, hyaluronic acid and sodium alginate with metals, aiming at improving the management of diabetic wounds. This review delineates the roles of key metals in human physiology and evaluates the application of metal ions in diabetic wound management strategies.

T cell metabolism in kidney immune homeostasis

Kidney immune homeostasis is intricately linked to T cells. Inappropriate differentiation, activation, and effector functions of T cells lead to a spectrum of kidney disease. While executing immune functions, T cells undergo a series of metabolic rewiring to meet the rapid energy demand. The key enzymes and metabolites involved in T cell metabolism metabolically and epigenetically modulate T cells' differentiation, activation, and effector functions, thereby being capable of modulating kidney immune homeostasis. In this review, we first summarize the latest advancements in T cell immunometabolism. Second, we outline the alterations in the renal microenvironment under certain kidney disease conditions. Ultimately, we highlight the metabolic modulation of T cells within kidney immune homeostasis, which may shed light on new strategies for treating kidney disease.

The ratio of non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol is associated with diabetic kidney disease: A cross-sectional study

Non-High-Density Lipoprotein Cholesterol to High-Density Lipoprotein Cholesterol Ratio (NHHR) is a significant indicator of atherosclerosis. However, its association with diabetic kidney disease (DKD) remains unclear. This study aims to explore the relationship between NHHR and the prevalence of DKD among the U.S. adults using data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2020. Participants were selected based on the stringent inclusion and exclusion criteria. We utilized single-factor analysis, multivariate logistic regression, and smooth curve fitting to investigate the relationship between NHHR and DKD. Our study included 8,329 diabetic individuals, who were categorized into DKD and non-DKD groups based on the presence or absence of kidney damage. A significant difference in NHHR was observed between these groups. After adjusting for potential confounders, we found that NHHR was positively associated with the prevalence of DKD. Specifically, each one-unit increase in NHHR corresponded to a 6% rise in the prevalence of DKD, with this association remaining significant across stratified NHHR values. Threshold effect analysis revealed an inflection point at an NHHR of 1.75, beyond this point, each unit increase in NHHR was associated with a 7% increase in the prevalence of DKD. Subgroup analysis confirmed the robustness of these findings. Our study demonstrates a significant correlation between NHHR and DKD prevalence, suggesting that monitoring NHHR could be an effective strategy for reducing DKD prevalence.

Identification of Spatial Specific Lipid Metabolic Signatures in Long-Standing Diabetic Kidney Disease

Background: Diabetic kidney disease (DKD) is a major complication of diabetes leading to kidney failure. Methods: This study investigates lipid metabolism profiles of long-standing DKD (LDKD, diabetes duration > 10 years) by integrative analysis of available single-cell RNA sequencing and spatial multi-omics data (focusing on spatial continuity samples) from the Kidney Precision Medicine Project. Results: Two injured cell types, an injured thick ascending limb (iTAL) and an injured proximal tubule (iPT), were identified and significantly elevated in LDKD samples. Both iTAL and iPT exhibit increased lipid metabolic and biosynthetic activities and decreased lipid and fatty acid oxidative processes compared to TAL/PT cells. Notably, compared to PT, iPT shows significant upregulation of specific injury and fibrosis-related genes, including FSHR and BMP7. Meanwhile, comparing iTAL to TAL, inflammatory-related genes such as ANXA3 and IGFBP2 are significantly upregulated. Furthermore, spatial metabolomics analysis reveals regionally distributed clusters in the kidney and notably differentially expressed lipid metabolites, such as triglycerides, glycerophospholipids, and sphingolipids, particularly pronounced in the inner medullary regions. Conclusions: These findings provide an integrative description of the lipid metabolism landscape in LDKD, highlighting injury-associated cellular processes and potential molecular mechanisms.

The dual role of lipids in chronic kidney disease: Pathogenic culprits and therapeutic allies

Chronic kidney disease (CKD) is a significant health burden, with rising incidence and prevalence, attributed in part to increasing obesity and diabetes rates. Lipid accumulation in the kidney parenchyma and chronic, low-grade inflammation are believed to significantly contribute to the development and progression of CKD. The effect of dysregulated kidney lipid metabolism in CKD progression, including altered cholesterol and fatty acid metabolism contribute to glomerular and tubular cell injury through the activation of oxidative stress and inflammatory signalling cascades. In contrast, classes of endogenous specialized pro-resolving lipid mediators (SPMs) have been described that act to limit the inflammatory response and promote the resolution of inflammation. This review highlights our current understanding of how lipids can cause damage within the kidney, and classes of protective lipid metabolites that offer therapeutic benefits.

A semantic segmentation method to analyze retinal vascular parameters of diabetic nephropathy

Introduction

By using spectral domain optical coherence tomography (SD-OCT) to measure retinal blood vessels. The correlation between the changes of retinal vascular structure and the degree of diabetic nephropathy is analyzed with a full-pixel Semantic segmentation method.

Methods

A total of 120 patients with diabetic nephropathy who were treated in the nephrology department of Quzhou People's Hospital from March 2023 to March 2024 were selected and divided into three groups according to the urinary albumin creatinine ratio (UACR). The groups included simple diabetes group (UACR < 30 mg/g), microalbuminuria group (30 mg/g ≤ UACR <300 mg/g) and macroalbuminuria group (UACR ≥300 mg/g). SD-OCT was used to scan the arteries and veins in the superior temporal area B of the retina. The semantic segmentation method built into the SD-eye software was used to automatically identify the morphology and structure of the vessels and calculate the parameters of arteriovenous vessels. The parameters of arteriovenous vessels are as follows: outer diameter of the retinal artery (RAOD); inner diameter of the retinal artery (RALD); arterial wall thickness (AWT); arterial wall to lumen ratio (AWLR); cross sectional area of arterial wall (AWCSA); retinal vein outer diameter (RVOD); retinal vein inner diameter (RVLD); vein wall thickness (VWT); vein wall to lumen ratio (VWLR); cross sectional area of vein wall (VWCSA). Statistical analysis software was used to compare and analyze the parameters of retinal arteriovenous vessels of the three groups.

Results

The study revealed statistically significant differences in RAOD and RALD among the three groups (p < 0.05) with the RAOD and RALD of the macroalbuminuria group and microalbuminuria group being lower than those of the simple diabetes group. Conversely, there were no significant differences in AWT, AWLR and AWCSA among the three groups (p > 0.05). Additionally, the differences in RVOD and RVLD among the three groups were found to be statistically significant (p < 0.05) with the RVOD and RVLD of the simple diabetes group being lower than those of the microalbuminuria group and macroalbuminuria group. No significant differences were observed in VWT and VWL among the groups. Additionally, RVOD and RVLD were weakly associated with UACR (R = 0.247, p = 0.007; R = 0.210, p = 0.021). Full-pixel semantic segmentation method combined with OCT images is a new retinal vascular scanning technology, which can be used as a new method for early diagnosis of diabetic nephropathy. The structural changes of retinal vessels can be used to predict the severity of diabetic nephropathy during the development of diabetic nephropathy.

Interplay between the Redox System and Renal Tubular Transport

The kidney plays a critical role in maintaining the homeostasis of body fluid by filtration of metabolic wastes and reabsorption of nutrients. Due to the overload, a vast of energy is required through aerobic metabolism, which inevitably leads to the generation of reactive oxygen species (ROS) in the kidney. Under unstressed conditions, ROS are counteracted by antioxidant systems and maintained at low levels, which are involved in signal transduction and physiological processes. Accumulating evidence indicates that the reduction-oxidation (redox) system interacts with renal tubular transport. Redox imbalance or dysfunction of tubular transport leads to renal disease. Here, we discuss the ROS and antioxidant systems in the kidney and outline the metabolic dysfunction that is a common feature of renal disease. Importantly, we describe the key molecules involved in renal tubular transport and their relationship to the redox system and, finally, summarize the impact of their dysregulation on the pathogenesis and progression of acute and chronic kidney disease.

Novel Insights into Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a major complication of diabetes mellitus (DM), affecting over one-third of type 1 and nearly half of type 2 diabetes patients. As the leading cause of end-stage renal disease (ESRD) globally, DKD develops through a complex interplay of chronic hyperglycemia, oxidative stress, and inflammation. Early detection is crucial, with diagnosis based on persistent albuminuria and reduced estimated glomerular filtration rate (eGFR). Treatment strategies emphasize comprehensive management, including glycemic control, blood pressure regulation, and the use of nephroprotective agents such as angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), sodium-glucose cotransporter-2 (SGLT2) inhibitors, and glucagon-like peptide-1 (GLP-1) receptor agonists. Ongoing research explores novel therapies targeting molecular pathways and non-coding RNAs. Preventive measures focus on rigorous control of hyperglycemia and hypertension, aiming to mitigate disease progression. Despite therapeutic advances, DKD remains a leading cause of ESRD, highlighting the need for continued research to identify new biomarkers and innovative treatments.

Genetic association of lipid traits and lipid-related drug targets with normal tension glaucoma: a Mendelian randomization study for predictive preventive and personalized medicine

Background

Glaucoma is the leading cause of irreversible blindness worldwide. Normal tension glaucoma (NTG) is a distinct subtype characterized by intraocular pressures (IOP) within the normal range (< 21 mm Hg). Due to its insidious onset and optic nerve damage, patients often present with advanced conditions upon diagnosis. NTG poses an additional challenge as it is difficult to identify with normal IOP, complicating its prediction, prevention, and treatment. Observational studies suggest a potential association between NTG and abnormal lipid metabolism, yet conclusive evidence establishing a direct causal relationship is lacking. This study aims to explore the causal link between serum lipids and NTG, while identifying lipid-related therapeutic targets. From the perspective of predictive, preventive, and personalized medicine (PPPM), clarifying the role of dyslipidemia in the development of NTG could provide a new strategy for primary prediction, targeted prevention, and personalized treatment of the disease.

Working hypothesis and methods

In our study, we hypothesized that individuals with dyslipidemia may be more susceptible to NTG due to a dysregulation of microvasculature in optic nerve head. To verify the working hypothesis, univariable Mendelian randomization (UVMR) and multivariable Mendelian randomization (MVMR) were utilized to estimate the causal effects of lipid traits on NTG. Drug target MR was used to explore possible target genes for NTG treatment. Genetic variants associated with lipid traits and variants of genes encoding seven lipid-related drug targets were extracted from the Global Lipids Genetics Consortium genome-wide association study (GWAS). GWAS data for NTG, primary open angle glaucoma (POAG), and suspected glaucoma (GLAUSUSP) were obtained from FinnGen Consortium. For apolipoproteins, we used summary statistics from a GWAS study by Kettunen et al. in 2016. For metabolic syndrome, summary statistics were extracted from UK Biobank participants. In the end, these findings could help identify individuals at risk of NTG by screening for lipid dyslipidemia, potentially leading to new targeted prevention and personalized treatment approaches.

Results

Genetically assessed high-density cholesterol (HDL) was negatively associated with NTG risk (inverse-variance weighted [IVW] model: OR per SD change of HDL level = 0.64; 95% CI, 0.49-0.85; P = 1.84 × 10-3), and the causal effect was independent of apolipoproteins and metabolic syndrome (IVW model: OR = 0.29; 95% CI, 0.14-0.60; P = 0.001 adjusted by ApoB and ApoA1; OR = 0.70; 95% CI, 0.52-0.95; P = 0.023 adjusted by BMI, HTN, and T2DM). Triglyceride (TG) was positively associated with NTG risk (IVW model: OR = 1.62; 95% CI, 1.15-2.29; P = 6.31 × 10-3), and the causal effect was independent of metabolic syndrome (IVW model: OR = 1.66; 95% CI, 1.18-2.34; P = 0.003 adjusted by BMI, HTN, and T2DM), but not apolipoproteins (IVW model: OR = 1.71; 95% CI, 0.99-2.95; P = 0.050 adjusted by ApoB and ApoA1). Genetic mimicry of apolipoprotein B (APOB) enhancement was associated with lower NTG risks (IVW model: OR = 0.09; 95% CI, 0.03-0.26; P = 9.32 × 10-6).

Conclusions

Our findings supported dyslipidemia as a predictive causal factor for NTG, independent of other factors such as metabolic comorbidities. Among seven lipid-related drug targets, APOB is a potential candidate drug target for preventing NTG. Personalized health profiles can be developed by integrating lipid metabolism with life styles, visual quality of life such as reading, driving, and walking. This comprehensive approach will aid in shifting from reactive medical services to PPPM in the management of NTG.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00373-5.

Molecular mechanism of renal lipid accumulation in diabetic kidney disease

Diabetic kidney disease (DKD) is a leading cause of end stage renal disease with unmet clinical demands for treatment. Lipids are essential for cell survival; however, renal cells have limited capability to metabolize overloaded lipids. Dyslipidaemia is common in DKD patients and renal ectopic lipid accumulation is associated with disease progression. Unveiling the molecular mechanism involved in renal lipid regulation is crucial for exploring potential therapeutic targets. In this review, we focused on the mechanism underlying cholesterol, oxysterol and fatty acid metabolism disorder in the context of DKD. Specific regulators of lipid accumulation in different kidney compartment and TREM2 macrophages, a lipid-related macrophages in DKD, were discussed. The role of sodium-glucose transporter 2 inhibitors in improving renal lipid accumulation was summarized.

Lipid metabolism disorder in diabetic kidney disease

Diabetic kidney disease (DKD), a significant complication associated with diabetes mellitus, presents limited treatment options. The progression of DKD is marked by substantial lipid disturbances, including alterations in triglycerides, cholesterol, sphingolipids, phospholipids, lipid droplets, and bile acids (BAs). Altered lipid metabolism serves as a crucial pathogenic mechanism in DKD, potentially intertwined with cellular ferroptosis, lipophagy, lipid metabolism reprogramming, and immune modulation of gut microbiota (thus impacting the liver-kidney axis). The elucidation of these mechanisms opens new potential therapeutic pathways for DKD management. This research explores the link between lipid metabolism disruptions and DKD onset.

Endothelial dysfunction in vascular complications of diabetes: a comprehensive review of mechanisms and implications

Diabetic vascular complications are prevalent and severe among diabetic patients, profoundly affecting both their quality of life and long-term prospects. These complications can be classified into macrovascular and microvascular complications. Under the impact of risk factors such as elevated blood glucose, blood pressure, and cholesterol lipids, the vascular endothelium undergoes endothelial dysfunction, characterized by increased inflammation and oxidative stress, decreased NO biosynthesis, endothelial-mesenchymal transition, senescence, and even cell death. These processes will ultimately lead to macrovascular and microvascular diseases, with macrovascular diseases mainly characterized by atherosclerosis (AS) and microvascular diseases mainly characterized by thickening of the basement membrane. It further indicates a primary contributor to the elevated morbidity and mortality observed in individuals with diabetes. In this review, we will delve into the intricate mechanisms that drive endothelial dysfunction during diabetes progression and its associated vascular complications. Furthermore, we will outline various pharmacotherapies targeting diabetic endothelial dysfunction in the hope of accelerating effective therapeutic drug discovery for early control of diabetes and its vascular complications.

Endothelial CXCR2 deficiency attenuates renal inflammation and glycocalyx shedding through NF-κB signaling in diabetic kidney disease

BACKGROUND

The incidence of diabetic kidney disease (DKD) continues to rapidly increase, with limited available treatment options. One of the hallmarks of DKD is persistent inflammation, but the underlying molecular mechanisms of early diabetic kidney injury remain poorly understood. C-X-C chemokine receptor 2 (CXCR2), plays an important role in the progression of inflammation-related vascular diseases and may bridge between glomerular endothelium and persistent inflammation in DKD.

METHODS

Multiple methods were employed to assess the expression levels of CXCR2 and its ligands, as well as renal inflammatory response and endothelial glycocalyx shedding in patients with DKD. The effects of CXCR2 on glycocalyx shedding, and persistent renal inflammation was examined in a type 2 diabetic mouse model with Cxcr2 knockout specifically in endothelial cells (DKD-Cxcr2 eCKO mice), as well as in glomerular endothelial cells (GECs), cultured in high glucose conditions.

RESULTS

CXCR2 was associated with early renal decline in DKD patients, and endothelial-specific knockout of CXCR2 significantly improved renal function in DKD mice, reduced inflammatory cell infiltration, and simultaneously decreased the expression of proinflammatory factors and chemokines in renal tissue. In DKD conditions, glycocalyx shedding was suppressed in endothelial Cxcr2 knockout mice compared to Cxcr2 L/L mice. Modulating CXCR2 expression also affected high glucose-induced inflammation and glycocalyx shedding in GECs. Mechanistically, CXCR2 deficiency inhibited the activation of NF-κB signaling, thereby regulating inflammation, restoring the endothelial glycocalyx, and alleviating DKD.

CONCLUSIONS

Taken together, under DKD conditions, activation of CXCR2 exacerbates inflammation through regulation of the NF-κB pathway, leading to endothelial glycocalyx shedding and deteriorating renal function. Endothelial CXCR2 deficiency has a protective role in inflammation and glycocalyx dysfunction, suggesting its potential as a promising therapeutic target for DKD treatment.

Oxidative Stress Induced by Lipotoxicity and Renal Hypoxia in Diabetic Kidney Disease and Possible Therapeutic Interventions: Targeting the Lipid Metabolism and Hypoxia

Oxidative stress, a hallmark pathophysiological feature in diabetic kidney disease (DKD), arises from the intricate interplay between pro-oxidants and anti-oxidants. While hyperglycemia has been well established as a key contributor, lipotoxicity emerges as a significant instigator of oxidative stress. Lipotoxicity encompasses the accumulation of lipid intermediates, culminating in cellular dysfunction and cell death. However, the mechanisms underlying lipotoxic kidney injury in DKD still require further investigation. The key role of cell metabolism in the maintenance of cell viability and integrity in the kidney is of paramount importance to maintain proper renal function. Recently, dysfunction in energy metabolism, resulting from an imbalance in oxygen levels in the diabetic condition, may be the primary pathophysiologic pathway driving DKD. Therefore, we aim to shed light on the pivotal role of oxidative stress related to lipotoxicity and renal hypoxia in the initiation and progression of DKD. Multifaceted mechanisms underlying lipotoxicity, including oxidative stress with mitochondrial dysfunction, endoplasmic reticulum stress activated by the unfolded protein response pathway, pro-inflammation, and impaired autophagy, are delineated here. Also, we explore potential therapeutic interventions for DKD, targeting lipotoxicity- and hypoxia-induced oxidative stress. These interventions focus on ameliorating the molecular pathways of lipid accumulation within the kidney and enhancing renal metabolism in the face of lipid overload or ameliorating subsequent oxidative stress. This review highlights the significance of lipotoxicity, renal hypoxia-induced oxidative stress, and its potential for therapeutic intervention in DKD.

Therapeutic strategies targeting the endothelial glycocalyx

PURPOSE OF REVIEW

This review will highlight recent studies that have examined the endothelial glycocalyx in a variety of health conditions, as well as potential glycocalyx-targeted therapies.

RECENT FINDINGS

A degraded glycocalyx is present in individuals that consume high sodium diet or have kidney disease, diabetes, preeclampsia, coronavirus disease 2019 (COVID-19), or sepsis. Specifically, these conditions are accompanied by elevated glycocalyx components in the blood, such as syndecan-1, syndecans-4, heparin sulfate, and enhanced heparinase activity. Impaired glycocalyx barrier function is accompanied by decreased nitric oxide bioavailability, increased leukocyte adhesion to endothelial cells, and vascular permeability. Glycocalyx degradation appears to play a key role in the progression of cardiovascular complications. However, studies that have used glycocalyx-targeted therapies to treat these conditions are scarce. Various therapeutics can restore the glycocalyx in kidney disease, diabetes, COVID-19, and sepsis. Exposing endothelial cells to glycocalyx components, such as heparin sulfate and hyaluronan protects the glycocalyx.

SUMMARY

We conclude that the glycocalyx is degraded in a variety of health conditions, although it remains to be determined whether glycocalyx degradation plays a causal role in disease progression and severity, and whether glycocalyx-targeted therapies improve patient health outcomes. Future studies are warranted to investigate therapeutic strategies that target the endothelial glycocalyx.

CircRNA itchy E3 ubiquitin protein ligase improves mitochondrial dysfunction in sepsis-induced acute kidney injury by targeting microRNA-214-3p/ATP-binding cassette A1 axis

BACKGROUND

Circular RNAs (circRNAs) are promising biomarkers and therapeutic targets for acute kidney injury (AKI). In this study, we investigated the mechanism by which circRNA itchy E3 ubiquitin protein ligase (circ-ITCH) regulates sepsis-induced AKI.

METHODS

A sepsis-induced AKI mouse model was created using LPS induction and circ-ITCH overexpression. Circ-ITCH levels were confirmed via RT-qPCR. Kidney tissue changes were examined through various stains and TUNEL. Enzyme-linked immunosorbent assay (ELISA) gauged oxidative stress and inflammation. Mitochondrial features were studied with electron microscopy. RT-qPCR and western blotting assessed mitochondrial function parameters. Using starBase, binding sites between circ-ITCH and miR-214-3p, as well as miR-214-3p and ABCA1, were predicted. Regulatory connections were proven by dual-luciferase assay, RT-qPCR, and western blotting.

RESULTS

Circ-ITCH expression was downregulated in LPS-induced sepsis mice. Overexpression of circ-ITCH ameliorates indicators of renal function (serum creatinine [SCr], blood urea nitrogen [BUN], neutrophil gelatinase-associated lipocalin [NGAL], and kidney injury molecule-1 [Kim-1]), reduces renal cell apoptosis, mitigates oxidative stress markers (reactive oxygen species [ROS] and malondialdehyde [MDA]), and diminishes inflammatory markers (interleukin [IL]-1β, IL-6, and tumor necrosis factor [TNF-α]). Moreover, circ-ITCH overexpression alleviated mitochondrial damage and dysfunction. Furthermore, circ-ITCH acts as a sponge for miR-214-3p, thereby upregulating ABCA1 expression. In addition, the miR-214-3p inhibitor repressed oxidative stress, inflammation, and mitochondrial dysfunction, which was reversed by circ-ITCH knockdown. Further cellular analysis in HK-2 cells supported these findings, highlighting the protective role of circ-ITCH against sepsis-induced AKI, particularly through the miR-214-3p/ABCA1 axis.

CONCLUSION

The novel circ-ITCH/miR-214-3p/ABCA1 pathway plays an essential role in the regulation of oxidative stress and mitochondrial dysfunction in sepsis-induced AKI.

Glutaredoxin 1 regulates cholesterol metabolism and gallstone formation by influencing protein S-glutathionylation

OBJECTIVE

Cholesterol gallstone disease (CGD) is closely related to cholesterol metabolic disorder. Glutaredoxin-1 (Glrx1) and Glrx1-related protein S-glutathionylation are increasingly being observed to drive various physiological and pathological processes, especially in metabolic diseases such as diabetes, obesity and fatty liver. However, Glrx1 has been minimally explored in cholesterol metabolism and gallstone disease.

METHODS

We first investigated whether Glrx1 plays a role in gallstone formation in lithogenic diet-fed mice using immunoblotting and quantitative real-time PCR. Then a whole-body Glrx1-deficient (Glrx1^-/-) mice and hepatic-specific Glrx1-overexpressing (AAV8-TBG-Glrx1) mice were generated, in which we analyzed the effects of Glrx1 on lipid metabolism upon LGD feeding. Quantitative proteomic analysis and immunoprecipitation (IP) of glutathionylated proteins were performed.

RESULTS

We found that protein S-glutathionylation was markedly decreased and the deglutathionylating enzyme Glrx1 was greatly increased in the liver of lithogenic diet-fed mice. Glrx1^-/- mice were protected from gallstone disease induced by a lithogenic diet because their biliary cholesterol and cholesterol saturation index (CSI) were reduced. Conversely, AAV8-TBG-Glrx1 mice showed greater gallstone progression with increased cholesterol secretion and CSI. Further studies showed that Glrx1-overexpressing greatly induced bile acid levels and/or composition to increase intestinal cholesterol absorption by upregulating Cyp8b1. In addition, liquid chromatography-mass spectrometry and IP analysis revealed that Glrx1 also affected the function of asialoglycoprotein receptor 1 (ASGR1) by mediating its deglutathionylation, thereby altering the expression of LXRα and controlling cholesterol secretion.

CONCLUSION

Our findings present novel roles of Glrx1 and Glrx1-regulated protein S-glutathionylation in gallstone formation through the targeting of cholesterol metabolism. Our data advises Glrx1 significantly increased gallstone formation by simultaneously increase bile-acid-dependent cholesterol absorption and ASGR1- LXRα-dependent cholesterol efflux. Our work suggests the potential effects of inhibiting Glrx1 activity to treat cholelithiasis.