NLRP3 deficiency ameliorates renal inflammation and fibrosis in diabetic mice

Eleutherococcus senticosus Alleviates Aristolochic-Acid-Induced Acute Kidney Damage by Inhibiting the NLRP3/IL-1β Signaling Pathway in Mice

Eleutherococcus senticosus (ES) exerts various pharmacological effects, including renoprotection in a rat model of renal ischemia-reperfusion injury. However, the mechanisms of these effects remain unclear. Therefore, we investigated the effects and mechanisms of ES on aristolochic acid (AA)-induced acute kidney injury in mice. The experimental mice were divided into the control group, the model group (AA-induced acute kidney injury model), the model + ES group (Eleutherococcus senticosus boiled-free granules treated by gavage for two weeks), the model + fasudil group (fasudil administered intraperitoneally for three days), and the model + ES + fasudil group. After AA intervention in normal mice, the expression of ASC and NLRP3 and the levels of IL-1β, IL-18, and TNF-α were significantly elevated in mouse renal tissues (P < 0.05). However, AA-induced renal dysfunction was ameliorated by both ES and fasudil, which was confirmed by the decrease in serum creatinine and blood urea nitrogen levels, as well as by renal histopathological abnormalities such as renal tubule dilation and tubular formation. In addition, the inflammatory response of AA-induced renal inflammation was inhibited by both ES and fasudil, and the expression of ASC and NLRP3 and the levels of IL-1β, IL-18, and TNF-α were significantly higher in mouse renal tissues after the treatment of either ES or fasudil (P < 0.05). ES may be a potential treatment agent for aristolochic-acid-triggered nephropathy, with inhibition of the NLRP3/IL-1β as one plausible underlying mechanism.

Acacetin Prevents Renal Damage Induced by Streptozotocin via Altering the NF-κB/ASC/NLRP3 and AMPK/SIRT1 Pathways in Mice

Diabetic nephropathy (DN) is the most common cause of end-stage renal disease. Its pathogenesis includes inflammation, an excess of reactive oxygen species, and kidney damage. The present study intended to explore the nephroprotective effects of acacetin (ACN) in streptozotocin-induced diabetic animals. The following are the experimental groups: One millilitre of 0.9% saline was given to Group I (control), Streptozotocin (STZ) (diabetic animals) + 0.9% saline to Group II (DN group) (negative control), DN + ACN (15 mg/kg body weight [bw]) to Group III, and DN + Valsartan (150 mg/kg bw) to Group IV. According to the findings, ACN decreased the levels of glucose, serum creatinine (Scr), blood urea nitrogen (BUN), malondialdehyde (MDA), and proinflammatory cytokines while increasing the bw, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in comparison to the DN animals. The histopathological analysis revealed that the animals treated with ACN showed recovery of renal damage in the tissues caused by STZ. In the STZ-induced DN mice, ACN reduced renal damage by upregulating the proteins of 5' adenosine monophosphate-activated protein kinase (AMPK), p-AMPK, and SIRT1 and downregulating the proteins of TGF-β, COL-1, COL-IV, NF-κB, ASC, NLRP3, and GSDMD, according to western blot analysis. Hence, the current study demonstrated that the regulation of the AMPK/SIRT1 and NF-κB/ASC/NLRP3 inflammasome pathways in DN mice was responsible for the protective effects of ACN. ACN may therefore be a viable treatment option for DN.

NR4A1 silencing alleviates high-glucose-stimulated HK-2 cells pyroptosis and fibrosis via hindering NLRP3 activation and PI3K/AKT pathway

BACKGROUND

The pathophysiology of diabetic kidney disease (DKD) is complex. Interfering with the processes of pyroptosis and fibrosis is an effective strategy for slowing DKD progression. Previous studies have revealed that nuclear receptor subfamily 4 group A member 1 (NR4A1) may serve as a novel pathogenic element in DKD; however, the specific mechanism by which it contributes to pyroptosis and fibrosis in DKD is unknown.

AIM

To investigate the role of NR4A1 in renal pyroptosis and fibrosis in DKD and possible molecular mechanisms.

METHODS

Streptozotocin 60 mg/kg was injected intraperitoneally to establish a rat model of DKD. Typically, 45 mmol/L glucose [high glucose (HG)] was used to activate HK-2 cells to mimic the DKD model in vitro. HK-2 cells were transfected with NR4A1 siRNA to silence NR4A1.

RESULTS

NR4A1 was elevated in renal tissues of DKD rats and HG-stimulated HK-2 cells. Concurrently, NOD-like receptor protein 3 (NLRP3) and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathways were triggered, and pyroptosis and expression of fibrosis-linked elements was increased in vivo and in vitro. These alterations were significantly reversed via NR4A1 silencing.

CONCLUSION

Inhibition of NR4A1 mitigated pyroptosis and fibrosis via suppressing NLRP3 activation and the PI3K/AKT pathway in HG-activated HK-2 cells.

Transcriptome and single-cell profiling of the mechanism of diabetic kidney disease

BACKGROUND

The NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome may play an important role in diabetic kidney disease (DKD). However, the exact link remains unclear.

AIM

To investigate the role of the NLRP3 inflammasome in DKD.

METHODS

Using datasets from the Gene Expression Omnibus database, 30 NLRP3 inflammasome-related genes were identified. Differentially expressed genes were selected using differential expression analysis, whereas intersecting genes were selected based on overlapping differentially expressed genes and NLRP3 inflammasome-related genes. Subsequently, three machine learning algorithms were used to screen genes, and biomarkers were identified by overlapping the genes from the three algorithms. Potential biomarkers were validated by western blotting in a db/db mouse model of diabetes.

RESULTS

Two biomarkers, sirtuin 2 (SIRT2) and caspase 1 (CASP1), involved in the Leishmania infection pathway were identified. Both biomarkers were expressed in endothelial cells. Pseudo-temporal analysis based on endothelial cells showed that DKD mostly occurs during the mid-differentiation stage. Western blotting results showed that CASP1 expression was higher in the DKD group than in the control group (P < 0.05), and SIRT2 content decreased (P < 0.05).

CONCLUSION

SIRT2 and CASP1 provide a potential theoretical basis for DKD treatment.

Novel approach to alleviate lupus nephritis: targeting the NLRP3 inflammasome in CD8+CD69+CD103+ TRM cells

BACKGROUND

Renal CD8+ tissue-resident memory T (TRM) cells display prolonged survival and activity in lupus nephritis (LN), exacerbating renal pathology. NLRP3 regulates the T cell response. This study explored the impact of NLRP3 inflammasome activity on the regulatory functions of TRM cells in LN.

METHODS

NLRP3 inflammasome activity in renal CD8+ TRM cells from lupus-prone MRL/lpr mice and in vitro induced human CD8+CD103+ T cells was assessed by quantifying NLRP3, caspase-1, gasdermin D (GSDMD), and IL-1β levels using flow cytometry, ELISA, and western blotting analysis. The specific NLRP3 inhibitor MCC950, caspase-1 inhibitor Ac-YVAD-cmk, and NF-κB inhibitor JSH23 were utilized to delineate the role of NLRP3 in modulating the pathogenicity of CD8+ TRM cells in LN.

RESULTS

Activation of the NLRP3 inflammasome was confirmed in renal CD8+CD69+CD103+ TRM cells derived from mice with LN and in vitro-induced human CD8+CD103+ TRM-like cells. MCC950 curtailed the infiltration and activity of CD8+CD69+CD103+ TRM cells and enhanced renal outcomes. MCC950 also suppressed the maturation and functional capabilities of CD8+CD103+ T cells in a manner reliant on inflammasome activity in vitro. IL-1β promoted the expression of TGF-βRII in CD8+ T cells via the NF-κB pathway.

CONCLUSIONS

NLRP3 inflammasome activity in renal CD8+CD69+CD103+ TRM cells contributes to LN pathogenesis by regulating cell differentiation and effector functions. Therapeutically targeting the NLRP3 inflammasome could significantly mitigate CD8+CD69+CD103+ TRM cell-mediated renal damage in LN.

Fucoidan Supplementation Relieved Kidney Injury and Modulated Intestinal Homeostasis in Hyperuricemia Mice

Hyperuricemia is a metabolic disease characterized by an excessively increased level of uric acid (UA) in the blood, with an increasing prevalence and often associated with kidney damage. Gut microbiota and endotoxins of gut origin are key mediators in the gut-kidney axis that can cause renal impairment. The study was to reveal the protective effects of fucoidan on renal injury caused by hyperuricemia. The hyperuricemia model was established in C57BL/6J mice. After 10 weeks of fucoidan supplementation, we found that the levels of serum UA and creatinine were reduced, and the levels of renal tumor necrosis factor α, interleukin-18 (IL-18), IL-6, and interleukin-1β (IL-1β) were also decreased. Fucoidan inhibited the expressions of phosphorylated NF-κB p65, NLRP3, and activated caspase-1 in the kidneys. Fucoidan also regulated the expressions of Bcl-2 family proteins and decreased the activation of caspase-3, thereby exerting antiapoptotic effect. In addition, fucoidan could reduce the expressions of glucose transporter 9 (GLUT9) and urate transporter 1 (URAT1) proteins, thereby promoting the excretion of UA from the kidneys. Moreover, the protective effect of fucoidan on renal injury may be related to maintaining intestinal homeostasis. Fucoidan reduced serum lipopolysaccharide and improved the intestinal mucosal barrier function. Fucoidan decreased the abundances of Blautia, Muribaculaceae, and Dubosiella, and increased the abundances of Lactobacillus. High-dose fucoidan supplementation increased the content of butyric acid and enhanced the expression of ATP binding box transporter G2 (ABCG2) via the AMPK/AKT/CREB pathway in ileum. Conclusion: Fucoidan could protect against hyperuricemia-induced renal injury by inhibiting renal inflammation and apoptosis and modulating intestinal homeostasis in hyperuricemia mice.

Nox4 is involved in acute kidney injury associated to intravascular hemolysis

Massive intravascular hemolysis occurs not unfrequently in many clinical conditions. Breakdown of erythrocytes promotes the accumulation of heme-derivates in the kidney, increasing oxidative stress and cell death, thus promoting acute kidney injury (AKI). NADPH oxidase 4 (Nox4) is a major source of reactive oxygen species (ROS) in the kidney, however it is unknown the role of Nox4 in hemolysis and whether inhibition of this enzyme may protect from heme-mediated injury. To answer these questions, we elicited intravascular hemolysis in wild type and Nox4 knockout mice. We also evaluated whether nephrotoxic effects of heme may be reduced by using Nox4 siRNA and pharmacologic inhibition with GKT137831, a Nox4 inhibitor, both in vivo and in cultured renal cells. Our results showed that induction of massive hemolysis elicited AKI characterized by loss of renal function, morphological alterations of the tubular epithelium and podocytes, oxidative stress, inflammation, mitochondrial dysfunction, blockade of autophagy and cell death. These pathological effects were significantly prevented in Nox4-deficient mice and in animals treated with GKT137831. In vitro studies showed that Nox4 disruption by specific siRNAs or Nox4 inhibitors declined heme-mediated ROS production and cell death. Our data identify Nox4 as a key enzyme involved in intravascular hemolysis-induced AKI. Thus, Nox4 inhibition may be a potential therapeutic approach to prevent renal damage in patients with severe hemolytic crisis.

SGLT2 inhibitors and NLRP3 inflammasome: potential target in diabetic kidney disease

Diabetic kidney disease (DKD) remains the leading cause of chronic kidney disease (CKD) worldwide. The pathogenesis of DKD is influenced by functional, histopathological, and immune mechanisms, including NLRP3 inflammasome activity and oxidative stress. The sodium-glucose cotransporter 2 inhibitors (SGLT2i) have shown metabolic benefits and the ability to slow the progression of DKD in several clinical studies over the years. Recent studies suggest that the antidiabetic activity also extends to inhibition of the inflammatory response, including modulation of the NLRP3 inflammasome, reduction of pro-inflammatory markers and reduction of oxidative stress. Here we review the efficacy of SGLT2i in the treatment of CKD and discuss the role of the inflammatory response in the development of DKD, including its relationship to the NLRP3 inflammasome and oxidative stress.

Oridonin Attenuates Diabetes‑induced Renal Fibrosis via the Inhibition of TXNIP/NLRP3 and NF‑κB Pathways by Activating PPARγ in Rats

INTRODUCTION

Oridonin possesses remarkable anti-inflammatory, immunoregulatory properties. However, the renoprotective effects of oridonin and the underlying molecular mechanisms in diabetic nephropathy (DN). We hypothesized that oridonin could ameliorate diabetes‑induced renal fibrosis.

METHODS

Streptozocin (STZ)-induced diabetic rats were provided with a high-fat diet to establish a type 2 diabetes mellitus (T2DM) animal model, and then treated with Oridonin (10, 20 mg/kg/day) for two weeks. Kidney function and renal fibrosis were assessed. High glucose-induced human renal proximal tubule epithelial cells (HK-2) were also treated with oridonin. The expression of inflammatory factors and fibrotic markers were analyzed.

RESULTS

Oridonin treatment preserved kidney function and markedly limited the renal fibrosis size in diabetic rats. The renal fibrotic markers were inhibited in the oridonin 10 mg/kg/day and 20 mg/kg/day groups compared to the T2DM group. The expression of thioredoxin-interacting proteins/ nod-like receptor protein-3 (TXNIP/NLRP3) and nuclear factor (NF)‑κB pathway decreased, while that of peroxisome proliferator-activated receptor-gamma (PPARγ) increased in the oridonin treatment group compared to the non-treated group. In vitro, PPARγ intervention could significantly regulate the effect of oridonin on the high glucose-induced inflammatory changes in HK-2 cells.

CONCLUSION

Oridonin reduces renal fibrosis and preserves kidney function via the inhibition of TXNIP/NLRP3 and NF‑κB pathways by activating PPARγ in rat T2DM model, which indicates potential effect of oridonin in the treatment of DN.

Fiery Connections: Macrophage-Mediated Inflammation, the Journey from Obesity to Type 2 Diabetes Mellitus and Diabetic Kidney Disease

The high prevalence of diabetes mellitus (DM) poses a significant public health challenge, with diabetic kidney disease (DKD) as one of its most serious consequences. It has become increasingly clear that type 2 DM (T2D) and the complications of DKD are not purely metabolic disorders. This review outlines emerging evidence related to the step-by-step contribution of macrophages to the development and progression of DKD in individuals who specifically develop T2D as a result of obesity. The macrophage is a prominent inflammatory cell that contributes to obesity, where adipocyte hypertrophy leads to macrophage recruitment and eventually to the expansion of adipose tissue. The recruited macrophages secrete proinflammatory cytokines, which cause systemic inflammation, glucose dysregulation, and insulin sensitivity, ultimately contributing to the development of T2D. Under such pathological changes, the kidney is susceptible to elevated glucose and thereby activates signaling pathways that ultimately drive monocyte recruitment. In particular, the early recruitment of proinflammatory macrophages in the diabetic kidney produces inflammatory cytokines/chemokines that contribute to inflammation and tissue damage associated with DKD pathology. Macrophage activation and recruitment are crucial inciting factors that also persist as DKD progresses. Thus, targeting macrophage activation and function could be a promising therapeutic approach, potentially offering significant benefits for managing DKD at all stages of progression.

Loss of NLRP6 increases the severity of kidney fibrosis

While NLRP3 contributes to kidney fibrosis, the function of most NOD-like receptors (NLRs) in chronic kidney disease (CKD) remains unexplored. To identify further NLR members involved in the pathogenesis of CKD, we searched for NLR genes expressed by normal kidneys and differentially expressed in human CKD transcriptomics databases. For NLRP6, lower kidney expression correlated with decreasing glomerular filtration rate. The role and molecular mechanisms of Nlrp6 in kidney fibrosis were explored in wild-type and Nlrp6-deficient mice and cell cultures. Data mining of single-cell transcriptomics databases identified proximal tubular cells as the main site of Nlrp6 expression in normal human kidneys and tubular cell Nlrp6 was lost in CKD. We confirmed kidney Nlrp6 downregulation following murine unilateral ureteral obstruction. Nlrp6-deficient mice had higher kidney p38 MAPK activation and more severe kidney inflammation and fibrosis. Similar results were obtained in adenine-induced kidney fibrosis. Mechanistically, profibrotic cytokines transforming growth factor beta 1 (TGF-β1) and TWEAK decreased Nlrp6 expression in cultured tubular cells, and Nlrp6 downregulation resulted in increased TGF-β1 and CTGF expression through p38 MAPK activation, as well as in downregulation of the antifibrotic factor Klotho, suggesting that loss of Nlrp6 promotes maladaptive tubular cell responses. The pattern of gene expression following Nlrp6 targeting in cultured proximal tubular cells was consistent with maladaptive transitions for proximal tubular cells described in single-cell transcriptomics datasets. In conclusion, endogenous constitutive Nlrp6 dampens sterile kidney inflammation and fibrosis. Loss of Nlrp6 expression by tubular cells may contribute to CKD progression.

The role of perirenal adipose tissue deposition in chronic kidney disease progression: Mechanisms and therapeutic implications

Chronic kidney disease (CKD) represents a significant and escalating global health challenge, with morbidity and mortality rates rising steadily. Evidence increasingly implicates perirenal adipose tissue (PRAT) deposition as a contributing factor in the pathogenesis of CKD. This review explores how PRAT deposition may exert deleterious effects on renal structure and function. The anatomical proximity of PRAT to the kidneys not only potentially causes mechanical compression but also leads to the dysregulated secretion of adipokines and inflammatory mediators, such as adiponectin, leptin, visfatin, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and exosomes. Additionally, PRAT deposition may contribute to renal lipotoxicity through elevated levels of free fatty acids (FFA), triglycerides (TAG), diacylglycerol (DAG), and ceramides (Cer). PRAT deposition is also linked to the hyperactivation of the renin-angiotensin-aldosterone system (RAAS), which further exacerbates CKD progression. Recognizing PRAT deposition as an independent risk factor for CKD underscores the potential of targeting PRAT as a novel strategy for the prevention and management of CKD. This review further discusses interventions that could include measuring PRAT thickness to establish a baseline, managing metabolic risk factors that promote its deposition, and inhibiting key PRAT-induced signaling pathways.

Salvianolic acid B in fibrosis treatment: a comprehensive review

Fibrosis is a public health issue of great concern characterized by the excessive deposition of extracellular matrix, leading to the destruction of parenchymal tissue and organ dysfunction that places a heavy burden on the global healthcare system due to its high incidence, disability, and mortality. Salvianolic acid B (SalB) has positively affected various human diseases, including fibrosis. In this review, we concentrate on the anti-fibrotic effects of SalB from a molecular perspective while providing information on the safety, adverse effects, and drug interactions of SalB. Additionally, we discuss the innovative SalB formulations, which give some references for further investigation and therapeutic use of SalB's anti-fibrotic qualities. Even with the encouraging preclinical data, additional research is required before relevant clinical trials can be conducted. Therefore, we conclude with recommendations for future studies. It is hoped that this review will provide comprehensive new perspectives on future research and product development related to SalB treatment of fibrosis and promote the efficient development of this field.

Emerging insights into the role of NLRP3 inflammasome and endoplasmic reticulum stress in renal diseases

NLRP3 inflammasome is a key component of the innate immune system, mediating the activation of caspase-1, and the maturity and secretion of the pro-inflammatory cytokine interleukin (IL)-1beta (IL-1β) and IL-18 to cope with microbial infections and cell injury. The NLRP3 inflammasome is activated by various endogenous danger signals, microorganisms and environmental stimuli, including urate, extracellular adenosine triphosphate (ATP) and cholesterol crystals. Increasing evidence indicates that the abnormal activation of NLRP3 is involved in multiple diseases including renal diseases. Hence, clarifying the mechanism of action of NLRP3 inflammasome in different diseases can help prevent and treat various diseases. Endoplasmic reticulum (ER) is an important organelle which participates in cell homeostasis maintenance and protein quality control. The unfolded protein response (UPR) and ER stress are caused by the excessive accumulation of unfolded or misfolded proteins in ER to recover ER homeostasis. Many factors can cause ER stress, including inflammation, hypoxia, environmental toxins, viral infections, glucose deficiency, changes in Ca2+ level and oxidative stress. The dysfunction of ER stress participates in multiple diseases, such as renal diseases. Many previous studies have shown that NLRP3 inflammasome and ER stress play an important role in renal diseases. However, the relevant mechanisms are not yet fully clear. Herein, we focus on the current understanding of the role and mechanism of ER stress and NLRP3 inflammasome in renal diseases, hoping to provide theoretical references for future related researches.

Tanshinone IIA Promoted Autophagy and Inhibited Inflammation to Alleviate Podocyte Injury in Diabetic Nephropathy

Purpose

Tanshinone IIA (Tan-IIA) is widely used in patients with diabetic nephropathy (DN), but its protective effect on podocytes in DN has not been well studied. In this study, the effects of Tan-IIA on autophagy and inflammation of glomerular podocytes in DN were observed in vivo and in vitro, and the underlying mechanisms were investigated. Irbesartan, an angiotensin II receptor blocker, is a representative medication for the clinical treatment of DN. So irbesartan was chosen as a positive control drug.

Methods

Eight-week-old male db/db mice were randomly divided into a DN group, an irbesartan group, and three groups receiving different doses of Tan-IIA. The control group consisted of the db/m littermate mice. Blood, urine, and kidney samples were taken from the mice after 12 weeks of continuous administration. Renal protection of Tan-IIA was evaluated using enzyme-linked immunosorbent assay kits, haematoxylin and eosin staining, transmission electron microscopy, Western blotting, and immunohistochemistry. In vitro, the protective effect of Tan-IIA on podocytes was explored using MPC5 cells cultured with high glucose.

Results

Tan-IIA significantly improved renal pathological injury and relieved the renal dysfunction in DN. Compared with the DN group, Tan-IIA could up-regulate the expression of Synaptopodin, Podocin, LC3II/I and Beclin-1 (p < 0.05), and down-regulate the expression of p62, F4/80, NF-κB p65, IL-1β, TNF-α and IL-6 (p < 0.05) both in vivo and in vitro, suggesting that Tan-IIA treatment alleviated podocyte injury by promoting autophagy and inhibiting inflammation during DN. The levels of p-PI3K/PI3K, p-Akt/Akt and p-mTOR/mTOR in Tan-IIA group were lower than those in DN group (p < 0.05), indicating that Tan-IIA inhibited the PI3K/Akt/mTOR signalling pathway in podocytes, which was a key pathway in regulating both autophagy and inflammation.

Conclusion

Tan-IIA prevented podocyte injury in DN by fostering autophagy and inhibiting inflammation, at least in part via inhibition of the PI3K/Akt/mTOR signalling pathway.

Effect of NLRP3 gene knockdown on pyroptosis and ferroptosis in diabetic cardiomyopathy injury

Diabetic cardiomyopathy (DCM) is a chronic disease caused by diabetes mellitus, which is recognized as a worldwide challenging disease. This study aimed to investigate the role and the potential mechanism of knocking down the NACHT-, LRR- and PYD domains-containing protein 3 (NLRP3), an inflammasome associated with onset and progression of various diseases, on high glucose or diabetes -induced cardiac cells pyroptosis and ferroptosis, two regulated non-necrosis cell death modalities discovered recent years. In the present study, both in vivo and in vitro studies were conducted simultaneously. Diabetic rats were induced by 55 mg/kg intraperitoneal injection of streptozotocin (STZ). Following the intraperitoneal injection of MCC950 (10 mg/kg), On the other hand, the DCM model in H9C2 cardiac cells was simulated with 35 mmol/L glucose and a short hairpin RNA vector of NLRP3 were transfected to cells. The results showed that in vivo study, myocardial fibers were loosely arranged and showed inflammatory cell infiltration, mitochondrial cristae were broken and the GSDMD-NT expression was found notably increased in the DM group, while the protein expressions of xCT and GPX4 was significantly decreased, both of which were reversed by MCC950. High glucose reduced the cell viability and ATP level in vitro, accompanied by an increase in LDH release. All of the above indicators were reversed after NLRP3 knockdown compared with the HG treated alone. Moreover, the protein expressions of pyroptosis- and ferroptosis-related fators were significantly decreased or increased, consistent with the results shown by immunofluorescence. Furthermore, the protective effects of NLRP3 knockdown against HG were reversed following the mtROS agonist rotenone (ROT) treatment. In conclusion, inhibition of NLRP3 suppressed DM-induced myocardial injury. Promotion of mitochondrial ROS abolished the protective effect of knockdown NLRP3, and induced the happening of pyroptosis and ferroptosis. These findings may present a novel therapeutic underlying mechanism for clinical diabetes-induced myocardial injury treatment.

Inhibition of PKC-δ retards kidney fibrosis via inhibiting cGAS-STING signaling pathway in mice

Kidney fibrosis is considered to be the ultimate aggregation pathway of chronic kidney disease (CKD), but its underlying mechanism remains elusive. Protein kinase C-delta (PKC-δ) plays critical roles in the control of growth, differentiation, and apoptosis. In this study, we found that PKC-δ was highly upregulated in human biopsy samples and mouse kidneys with fibrosis. Rottlerin, a PKC-δ inhibitor, alleviated unilateral ureteral ligation (UUO)-induced kidney fibrosis, inflammation, VDAC1 expression, and cGAS-STING signaling pathway activation. Adeno-associated virus 9 (AAV9)-mediated VDAC1 silencing or VBIT-12, a VDAC1 inhibitor, attenuated renal injury, inflammation, and activation of cGAS-STING signaling pathway in UUO mouse model. Genetic and pharmacologic inhibition of STING relieved renal fibrosis and inflammation in UUO mice. In vitro, hypoxia resulted in PKC-δ phosphorylation, VDAC1 oligomerization, and activation of cGAS-STING signaling pathway in HK-2 cells. Inhibition of PKC-δ, VDAC1 or STING alleviated hypoxia-induced fibrotic and inflammatory responses in HK-2 cells, respectively. Mechanistically, PKC-δ activation induced mitochondrial membrane VDAC1 oligomerization via direct binding VDAC1, followed by the mitochondrial DNA (mtDNA) release into the cytoplasm, and subsequent activated cGAS-STING signaling pathway, which contributed to the inflammation leading to fibrosis. In conclusion, this study has indicated for the first time that PKC-δ is an important regulator in kidney fibrosis by promoting cGAS-STING signaling pathway which mediated by VDAC1. PKC-δ may be useful for treating renal fibrosis and subsequent CKD.

Tonabersat suppresses priming/activation of the NOD-like receptor protein-3 (NLRP3) inflammasome and decreases renal tubular epithelial-to-macrophage crosstalk in a model of diabetic kidney disease

BACKGROUND

Accompanied by activation of the NOD-like receptor protein 3 (NLRP3) inflammasome, aberrant connexin 43 (Cx43) hemichannel-mediated ATP release is situated upstream of inflammasome assembly and inflammation and contributes to multiple secondary complications of diabetes and associated cardiometabolic comorbidities. Evidence suggests there may be a link between Cx43 hemichannel activity and inflammation in the diabetic kidney. The consequences of blocking tubular Cx43 hemichannel-mediated ATP release in priming/activation of the NLRP3 inflammasome in a model of diabetic kidney disease (DKD) was investigated. We examined downstream markers of inflammation and the proinflammatory and chemoattractant role of the tubular secretome on macrophage recruitment and activation.

METHODS

Analysis of human transcriptomic data from the Nephroseq repository correlated gene expression to renal function in DKD. Primary human renal proximal tubule epithelial cells (RPTECs) and monocyte-derived macrophages (MDMs) were cultured in high glucose and inflammatory cytokines as a model of DKD to assess Cx43 hemichannel activity, NLRP3 inflammasome activation and epithelial-to-macrophage paracrine-mediated crosstalk. Tonabersat assessed a role for Cx43 hemichannels.

RESULTS

Transcriptomic analysis from renal biopsies of patients with DKD showed that increased Cx43 and NLRP3 expression correlated with declining glomerular filtration rate (GFR) and increased proteinuria. In vitro, Tonabersat blocked glucose/cytokine-dependant increases in Cx43 hemichannel-mediated ATP release and reduced expression of inflammatory markers and NLRP3 inflammasome activation in RPTECs. We observed a reciprocal relationship in which NLRP3 activity exacerbated increased Cx43 expression and hemichannel-mediated ATP release, events driven by nuclear factor kappa-B (NFκB)-mediated priming and Cx43 hemichannel opening, changes blocked by Tonabersat. Conditioned media (CM) from RPTECs treated with high glucose/cytokines increased expression of inflammatory markers in MDMs, an effect reduced when macrophages were pre-treated with Tonabersat. Co-culture using conditioned media from Tonabersat-treated RPTECs dampened macrophage inflammatory marker expression and reduced macrophage migration.

CONCLUSION

Using a model of DKD, we report for the first time that high glucose and inflammatory cytokines trigger aberrant Cx43 hemichannel activity, events that instigate NLRP3-induced inflammation in RPTECs and epithelial-to-macrophage crosstalk. Recapitulating observations previously reported in diabetic retinopathy, these data suggest that Cx43 hemichannel blockers (i.e., Tonabersat) may dampen multi-system damage observed in secondary complications of diabetes.

Research Progress of Pyroptosis in Diabetic Kidney Disease

Pyroptosis, known as one typical mode of programmed cell death, is generally characterized by the cleaved gasdermin family (GSDMs) forming pores in the cell membrane and inducing cell rupture, and the activation of aspartate-specific proteases (caspases) has also been found during this process. Diabetic Kidney Disease (DKD) is caused by the complication of diabetes in the kidney, and the most important kidney's function, Glomerular Filtration Rate (GFR), happens to drop to less than 90% of its usual and even lead to kidney failure in severe cases. The persistent inflammatory state induced by high blood glucose implies the key pathology of DKD, and growing evidence shows that pyroptosis serves as a significant contributor to this chronic immune-mediated inflammatory disorder. Currently, the expanded discovery of GSDMs, pyroptosis, and its association with innate immunity has been more attractive, and overwhelming research is needed to sort out the implication of pyroptosis in DKD pathology. In this review, we comb both classical studies and newly founds on pyroptosis, prick off the novel awakening of pyroptosis in DKD, and center on the significance of pyroptosis in DKD treatment, aiming to provide new research targets and treatment strategies on DKD.

Renal macrophages and NLRP3 inflammasomes in kidney diseases and therapeutics

Macrophages are exceptionally diversified cell types and perform unique features and functions when exposed to different stimuli within the specific microenvironment of various kidney diseases. In instances of kidney tissue necrosis or infection, specific patterns associated with damage or pathogens prompt the development of pro-inflammatory macrophages (M1). These M1 macrophages contribute to exacerbating tissue damage, inflammation, and eventual fibrosis. Conversely, anti-inflammatory macrophages (M2) arise in the same circumstances, contributing to kidney repair and regeneration processes. Impaired tissue repair causes fibrosis, and hence macrophages play a protective and pathogenic role. In response to harmful stimuli within the body, inflammasomes, complex assemblies of multiple proteins, assume a pivotal function in innate immunity. The initiation of inflammasomes triggers the activation of caspase 1, which in turn facilitates the maturation of cytokines, inflammation, and cell death. Macrophages in the kidneys possess the complete elements of the NLRP3 inflammasome, including NLRP3, ASC, and pro-caspase-1. When the NLRP3 inflammasomes are activated, it triggers the activation of caspase-1, resulting in the release of mature proinflammatory cytokines (IL)-1β and IL-18 and cleavage of Gasdermin D (GSDMD). This activation process therefore then induces pyroptosis, leading to renal inflammation, cell death, and renal dysfunction. The NLRP3-ASC-caspase-1-IL-1β-IL-18 pathway has been identified as a factor in the development of the pathophysiology of numerous kidney diseases. In this review, we explore current progress in understanding macrophage behavior concerning inflammation, injury, and fibrosis in kidneys. Emphasizing the pivotal role of activated macrophages in both the advancement and recovery phases of renal diseases, the article delves into potential strategies to modify macrophage functionality and it also discusses emerging approaches to selectively target NLRP3 inflammasomes and their signaling components within the kidney, aiming to facilitate the healing process in kidney diseases.

Inflammation in diabetes complications: molecular mechanisms and therapeutic interventions

At present, diabetes mellitus (DM) has been one of the most endangering healthy diseases. Current therapies contain controlling high blood sugar, reducing risk factors like obesity, hypertension, and so on; however, DM patients inevitably and eventually progress into different types of diabetes complications, resulting in poor quality of life. Unfortunately, the clear etiology and pathogenesis of diabetes complications have not been elucidated owing to intricate whole-body systems. The immune system was responsible to regulate homeostasis by triggering or resolving inflammatory response, indicating it may be necessary to diabetes complications. In fact, previous studies have been shown inflammation plays multifunctional roles in the pathogenesis of diabetes complications and is attracting attention to be the meaningful therapeutic strategy. To this end, this review systematically concluded the current studies over the relationships of susceptible diabetes complications (e.g., diabetic cardiomyopathy, diabetic retinopathy, diabetic peripheral neuropathy, and diabetic nephropathy) and inflammation, ranging from immune cell response, cytokines interaction to pathomechanism of organ injury. Besides, we also summarized various therapeutic strategies to improve diabetes complications by target inflammation from special remedies to conventional lifestyle changes. This review will offer a panoramic insight into the mechanisms of diabetes complications from an inflammatory perspective and also discuss contemporary clinical interventions.

Fluorofenidone attenuates renal fibrosis by inhibiting lysosomal cathepsin‑mediated NLRP3 inflammasome activation

Currently, no antifibrotic drug in clinical use can effectively treat renal fibrosis. Fluorofenidone (AKFPD), a novel pyridone agent, significantly reduces renal fibrosis by inhibiting the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome; however, the underlying mechanism of this inhibition is not fully understood. The present study aimed to reveal the molecular mechanism underlying the suppression of NLRP3 inflammasome activation by AKFPD. It investigated the effect of AKFPD on NLRP3 activation and lysosomal cathepsins in a unilateral ureteral obstruction (UUO) rat model, and hypoxia/reoxygenation (H/R)-treated HK-2 cells and murine peritoneal-derived macrophages (PDMs) stimulated with lipopolysaccharide (LPS) and ATP. The results confirmed that AKFPD suppressed renal interstitial fibrosis and inflammation by inhibiting NLRP3 inflammasome activation in UUO rat kidney tissues. In addition, AKFPD reduced the production of activated caspase-1 and maturation of IL-1β by suppressing NLRP3 inflammasome activation in H/R-treated HK-2 cells and murine PDMs stimulated with LPS and ATP. AKFPD also decreased the activities of cathepsins B, L and S both in vivo and in vitro. Notably, AKFPD downregulated cathepsin B expression and NLRP3 colocalization in the cytoplasm after lysosomal disruptions. Overall, the results suggested that AKFPD attenuates renal fibrosis by inhibiting lysosomal cathepsin-mediated activation of the NLRP3 inflammasome.

Astragaloside IV attenuates renal tubule injury in DKD rats via suppression of CD36-mediated NLRP3 inflammasome activation

Background

In recent years, diabetic kidney disease (DKD) has emerged as a prominent factor contributing to end-stage renal disease. Tubulointerstitial inflammation and lipid accumulation have been identified as key factors in the development of DKD. Earlier research indicated that Astragaloside IV (AS-IV) reduces inflammation and oxidative stress, controls lipid accumulation, and provides protection to the kidneys. Nevertheless, the mechanisms responsible for its protective effects against DKD have not yet been completely elucidated.

Purpose

The primary objective of this research was to examine the protective properties of AS-IV against DKD and investigate the underlying mechanism, which involves CD36, reactive oxygen species (ROS), NLR family pyrin domain containing 3 (NLRP3), and interleukin-1β (IL-1β).

Methods

The DKD rat model was created by administering streptozotocin along with a high-fat diet. Subsequently, the DKD rats and palmitic acid (PA)-induced HK-2 cells were treated with AS-IV. Atorvastatin was used as the positive control. To assess the therapeutic effects of AS-IV on DKD, various tests including blood sugar levels, the lipid profile, renal function, and histopathological examinations were conducted. The levels of CD36, ROS, NLRP3, Caspase-1, and IL-1β were detected using western blot analysis, PCR, and flow cytometry. Furthermore, adenovirus-mediated CD36 overexpression was applied to explore the underlying mechanisms through in vitro experiments.

Results

In vivo experiments demonstrated that AS-IV significantly reduced hyperglycemia, dyslipidemia, urinary albumin excretion, and serum creatinine levels in DKD rats. Additionally, it improved renal structural abnormalities and suppressed the expression of CD36, NLRP3, IL-1β, TNF-α, and MCP-1. In vitro experiments showed that AS-IV decreased CD36 expression, lipid accumulation, and lipid ROS production while inhibiting NLRP3 activation and IL-1β secretion in PA-induced HK-2 cells.

Conclusion

AS-IV alleviated renal tubule interstitial inflammation and tubule epithelial cell apoptosis in DKD rats by inhibiting CD36-mediated lipid accumulation and NLRP3 inflammasome activation.

PS-MPs promotes the progression of inflammation and fibrosis in diabetic nephropathy through NLRP3/Caspase-1 and TGF-β1/Smad2/3 signaling pathways

BACKGROUND

Diabetic nephropathy (DN) is a prevalent chronic microvascular complication of diabetes and the leading cause of end-stage renal disease (ESRD). Understanding the progressive etiology of DN is critical for the development of effective health policies and interventions. Recent research indicated that polystyrene microplastics (PS-MPs) contaminate our diets and accumulate in various organs, including the liver, kidneys, and muscles.

METHODS

In this study, ten-week-old db/db mice and db/m mice were fed. Besides, db/db mice were divided into two groups: PS-MPs group (oral administration of 0.5 µm PS-MPs) and an H2O group, and they were fed for three months. A type II diabetes model was established using db/db mice to investigate the effects of PS-MPs on body weight, blood glucose level, renal function, and renal fibrosis.

RESULTS

The results demonstrated that PS-MPs significantly exacerbated various biochemical indicators of renal tissue damage, including fasting blood glucose, serum creatinine, blood urea nitrogen, and blood uric acid. Additionally, PS-MPs worsened the pathological alterations and degree of fibrosis in renal tissue. An increased oxidative stress state and elevated levels of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1) were identified. Furthermore, PS-MPs significantly enhanced renal fibrosis by inhibiting the transition from epithelial cells to mesenchymal cells, specifically through the inhibition of the TGF-β/Smad signaling pathway. The expression levels of NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), Caspase-1, and cleaved Caspase-1, which are inflammasome proteins, were significantly elevated in the PS-MPs group.

CONCLUSION

The findings suggested that PS-MPs could aggravate kidney injury and renal fibrosis in db/db mice by promoting NLRP3/Caspase-1 and TGF-β1/Smads signaling pathways. These findings had implications for elucidating the role of PS-MPs in DN progression, underscoring the necessity for additional research and public health interventions.

Remimazolam attenuates inflammation and kidney fibrosis following folic acid injury

The transition of acute kidney injury (AKI) to chronic kidney disease (CKD) is characterized by intense inflammation and progressive fibrosis. Remimazolam is widely used for procedural sedation in intensive care units, such as AKI patients. Remimazolam has been shown to possess anti-inflammatory and organ-protective properties. However, the role of remimazolam in inflammation and renal fibrosis following AKI remains unclear. Here, we explored the effects of remimazolam on the inflammatory response and kidney fibrogenesis of mice subjected to folic acid (FA) injury. Our results showed that remimazolam treatment alleviated kidney damage and dysfunction. Mice treated with remimazolam presented less collagen deposition in FA-injured kidneys compared with FA controls, which was accompanied by a reduction of extracellular matrix proteins accumulation and fibroblasts activation. Furthermore, remimazolam treatment reduced inflammatory cells infiltration into the kidneys of mice with FA injury and inhibited proinflammatory or profibrotic molecules expression. Finally, remimazolam treatment impaired the activation of bone marrow-derived fibroblasts and blunted the transformation of macrophages to myofibroblasts in FA nephropathy. Additionally, the benzodiazepine receptor antagonist PK-11195 partially reversed the protective effect of remimazolam on the FA-injured kidneys. Overall, remimazolam attenuates the inflammatory response and renal fibrosis development following FA-induced AKI, which may be related to the peripheral benzodiazepine receptor pathway.

Identification of crosstalk genes relating to ECM-receptor interaction genes in MASH and DN using bioinformatics and machine learning

This study aimed to identify genes shared by metabolic dysfunction-associated fatty liver disease (MASH) and diabetic nephropathy (DN) and the effect of extracellular matrix (ECM) receptor interaction genes on them. Datasets with MASH and DN were downloaded from the Gene Expression Omnibus (GEO) database. Pearson's coefficients assessed the correlation between ECM-receptor interaction genes and cross talk genes. The coexpression network of co-expression pairs (CP) genes was integrated with its protein-protein interaction (PPI) network, and machine learning was employed to identify essential disease-representing genes. Finally, immuno-penetration analysis was performed on the MASH and DN gene datasets using the CIBERSORT algorithm to evaluate the plausibility of these genes in diseases. We found 19 key CP genes. Fos proto-oncogene (FOS), belonging to the IL-17 signalling pathway, showed greater centrality PPI network; Hyaluronan Mediated Motility Receptor (HMMR), belonging to ECM-receptor interaction genes, showed most critical in the co-expression network map of 19 CP genes; Forkhead Box C1 (FOXC1), like FOS, showed a high ability to predict disease in XGBoost analysis. Further immune infiltration showed a clear positive correlation between FOS/FOXC1 and mast cells that secrete IL-17 during inflammation. Combining the results of previous studies, we suggest a FOS/FOXC1/HMMR regulatory axis in MASH and DN may be associated with mast cells in the acting IL-17 signalling pathway. Extracellular HMMR may regulate the IL-17 pathway represented by FOS through the Mitogen-Activated Protein Kinase 1 (ERK) or PI3K-Akt-mTOR pathway. HMMR may serve as a signalling carrier between MASH and DN and could be targeted for therapeutic development.

Dihydroxyacetone phosphate accumulation leads to podocyte pyroptosis in diabetic kidney disease

Diabetic kidney disease (DKD) can lead to accumulation of glucose upstream metabolites due to dysfunctional glycolysis. But the effects of accumulated glycolysis metabolites on podocytes in DKD remain unknown. The present study examined the effect of dihydroxyacetone phosphate (DHAP) on high glucose induced podocyte pyroptosis. By metabolomics, levels of DHAP, GAP, glucose-6-phosphate and fructose 1, 6-bisphosphate were significantly increased in glomeruli of db/db mice. Furthermore, the expression of LDHA and PKM2 were decreased. mRNA sequencing showed upregulation of pyroptosis-related genes (Nlrp3, Casp1, etc.). Targeted metabolomics demonstrated higher level of DHAP in HG-treated podocytes. In vitro, ALDOB expression in HG-treated podocytes was significantly increased. siALDOB-transfected podocytes showed less DHAP level, mTORC1 activation, reactive oxygen species (ROS) production, and pyroptosis, while overexpression of ALDOB had opposite effects. Furthermore, GAP had no effect on mTORC1 activation, and mTORC1 inhibitor rapamycin alleviated ROS production and pyroptosis in HG-stimulated podocytes. Our findings demonstrate that DHAP represents a critical metabolic product for pyroptosis in HG-stimulated podocytes through regulation of mTORC1 pathway. In addition, the results provide evidence that podocyte injury in DKD may be treated by reducing DHAP.

Pharmacological functions of salidroside in renal diseases: facts and perspectives

Rhodiola rosea is a valuable functional medicinal plant widely utilized in China and other Asian countries for its anti-fatigue, anti-aging, and altitude sickness prevention properties. Salidroside, a most active constituent derived from Rhodiola rosea, exhibits potent antioxidative, hypoxia-resistant, anti-inflammatory, anticancer, and anti-aging effects that have garnered significant attention. The appreciation of the pharmacological role of salidroside has burgeoned over the last decade, making it a beneficial option for the prevention and treatment of multiple diseases, including atherosclerosis, Alzheimer's disease, Parkinson's disease, cardiovascular disease, and more. With its anti-aging and renoprotective effects, in parallel with the inhibition of oxidative stress and inflammation, salidroside holds promise as a potential therapeutic agent for kidney damage. This article provides an overview of the microinflammatory state in kidney disease and discuss the current therapeutic strategies, with a particular focus on highlighting the recent advancements in utilizing salidroside for renal disease. The potential mechanisms of action of salidroside are primarily associated with the regulation of gene and protein expression in glomerular endothelial cells, podocytes, renal tubule cells, renal mesangial cells and renal cell carcinoma cell, including TNF-α, TGF-β, IL-1β, IL-17A, IL-6, MCP-1, Bcl-2, VEGF, ECM protein, caspase-3, HIF-1α, BIM, as well as the modulation of AMPK/SIRT1, Nrf2/HO-1, Sirt1/PGC-1α, ROS/Src/Cav-1, Akt/GSK-3β, TXNIP-NLRP3, ERK1/2, TGF-β1/Smad2/3, PI3K/Akt, Wnt1/Wnt3a β-catenin, TLR4/NF-κB, MAPK, JAK2/STAT3, SIRT1/Nrf2 pathways. To the best of our knowledge, this review is the first to comprehensively cover the protective effects of salidroside on diverse renal diseases, and suggests that salidroside has great potential to be developed as a drug for the prevention and treatment of metabolic syndrome, cardiovascular and cerebrovascular diseases and renal complications.

The role of inflammasomes in human diseases and their potential as therapeutic targets

Inflammasomes are large protein complexes that play a major role in sensing inflammatory signals and triggering the innate immune response. Each inflammasome complex has three major components: an upstream sensor molecule that is connected to a downstream effector protein such as caspase-1 through the adapter protein ASC. Inflammasome formation typically occurs in response to infectious agents or cellular damage. The active inflammasome then triggers caspase-1 activation, followed by the secretion of pro-inflammatory cytokines and pyroptotic cell death. Aberrant inflammasome activation and activity contribute to the development of diabetes, cancer, and several cardiovascular and neurodegenerative disorders. As a result, recent research has increasingly focused on investigating the mechanisms that regulate inflammasome assembly and activation, as well as the potential of targeting inflammasomes to treat various diseases. Multiple clinical trials are currently underway to evaluate the therapeutic potential of several distinct inflammasome-targeting therapies. Therefore, understanding how different inflammasomes contribute to disease pathology may have significant implications for developing novel therapeutic strategies. In this article, we provide a summary of the biological and pathological roles of inflammasomes in health and disease. We also highlight key evidence that suggests targeting inflammasomes could be a novel strategy for developing new disease-modifying therapies that may be effective in several conditions.

The role of innate immunity in diabetic nephropathy and their therapeutic consequences

Diabetic nephropathy (DN) is an enduring condition that leads to inflammation and affects a substantial number of individuals with diabetes worldwide. A gradual reduction in glomerular filtration and emergence of proteins in the urine are typical aspects of DN, ultimately resulting in renal failure. Mounting evidence suggests that immunological and inflammatory factors are crucial for the development of DN. Therefore, the activation of innate immunity by resident renal and immune cells is critical for initiating and perpetuating inflammation. Toll-like receptors (TLRs) are an important group of receptors that identify patterns and activate immune responses and inflammation. Meanwhile, inflammatory responses in the liver, pancreatic islets, and kidneys involve inflammasomes and chemokines that generate pro-inflammatory cytokines. Moreover, the activation of the complement cascade can be triggered by glycated proteins. This review highlights recent findings elucidating how the innate immune system contributes to tissue fibrosis and organ dysfunction, ultimately leading to renal failure. This review also discusses innovative approaches that can be utilized to modulate the innate immune responses in DN for therapeutic purposes.

Adenine model of chronic renal failure in rats to determine whether MCC950, an NLRP3 inflammasome inhibitor, is a renopreventive

BACKGROUND

Chronic renal failure (CRF) is defined by a significant decline in renal function that results in decreased salt filtration and inhibition of tubular reabsorption, which ultimately causes volume enlargement. This study evaluated the potential renopreventive effects of the NLRP3 inflammasome inhibitor MCC950 in adenine-induced CRF in rats due to conflicting evidence on the effects of MCC950 on the kidney.

METHODS

Since the majority of the kidney tubular abnormalities identified in people with chronic renal disease are comparable to those caused by adding 0.75 percent of adenine powder to a rat's diet each day for four weeks, this method has received broad approval as a model for evaluating kidney damage. Throughout the test, blood pressure was checked weekly and at the beginning. Additionally, oxidative stress factors, urine sample examination, histological modifications, and immunohistochemical adjustments of caspase-3 and interleukin-1 beta (IL-1) levels in renal tissues were carried out.

RESULTS

Results revealed that MCC950, an inhibitor of the NLRP3 inflammasome, had a renopreventive effect, which was demonstrated by a reduction in blood pressure readings and an improvement in urine, serum, and renal tissue indicators that indicate organ damage. This was also demonstrated by the decrease in neutrophil gelatinase-associated lipocalin tubular expression (NGAL). The NLRP3 inflammasome inhibitor MCC950 was found to significantly alleviate the worsening renal cellular alterations evidenced by increased expression of caspase-3 and IL-1, according to immunohistochemical tests.

CONCLUSION

The NLRP3 inflammasome inhibitor MCC950 demonstrated renopreventive effects in the CRF rat model, suggesting that it might be used as a treatment strategy to stop the progression of CRF.

Hederagenin inhibits high glucose-induced fibrosis in human renal cells by suppression of NLRP3 inflammasome activation through reducing cathepsin B expression

Diabetic nephropathy is a major complication of diabetes mellitus and is related to dysfunction of renal cells. Hederagenin is a triterpenoid saponin from some Chinese herbs with anti-inflammatory and anti-diabetic activities. However, its role in diabetic nephropathy progression is still obscure. This study aimed to explore the effects of hederagenin on renal cell dysfunction in vitro. Human renal mesangial cells (HRMCs) and human renal proximal tubular epithelial cells (HRPTEpiCs) were cultured under high glucose (HG) conditions to mimic diabetic nephropathy-like injury. Cell proliferation was evaluated by CCK-8. mRNA and protein levels were determined by qRT-PCR and western blotting, respectively. The secretion levels of fibrosis-related biomarkers were analyzed by ELISA. Results showed that hederagenin reduced HG-induced proliferation increase in HRMCs and HRPTEpiCs. Hederagenin attenuated HG-induced increase in mRNA and protein expression of NLRP3, ASC, and IL-1β. Hederagenin also suppressed HG-induced increase in mRNA and secretion levels of FN, Col. IV, PAI-1, and TGF-β1. NLRP3 inhibitor MCC950 attenuated HG-induced fibrosis of renal cells, and its activator nigericin reversed the suppressive effect of hederagenin on HG-induced fibrosis. Bioinformatics analysis predicted cathepsin B (CTSB) as a target of hederagenin to modulate NOD-like receptor (NLR) pathway. Hederagenin decreased CTSB level, and CTSB overexpression reversed the suppressive effect of hederagenin on HG-induced NLRP3 inflammasome activation and fibrosis in HRMCs and HRPTEpiCs. In conclusion, hederagenin attenuates HG-induced fibrosis of renal cells by inhibiting NLRP3 inflammasome activation via reducing CTSB expression, indicating a therapeutic potential of hederagenin in diabetic nephropathy.

Triptolide protects against podocyte injury in diabetic nephropathy by activating the Nrf2/HO-1 pathway and inhibiting the NLRP3 inflammasome pathway

Objectives: Diabetic nephropathy (DN) is the most common microvascular complication of diabetes mellitus. This study investigated the mechanism of triptolide (TP) in podocyte injury in DN.Methods: DN mouse models were established by feeding with a high-fat diet and injecting with streptozocin and MPC5 podocyte injury models were induced by high-glucose (HG), followed by TP treatment. Fasting blood glucose and renal function indicators, such as 24 h urine albumin (UAlb), serum creatinine (SCr), blood urea nitrogen (BUN), and kidney/body weight ratio of mice were examined. H&E and TUNEL staining were performed for evaluating pathological changes and apoptosis in renal tissue. The podocyte markers, reactive oxygen species (ROS), oxidative stress (OS), serum inflammatory cytokines, nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway-related proteins, and pyroptosis were detected by Western blotting and corresponding kits. MPC5 cell viability and pyroptosis were evaluated by MTT and Hoechst 33342/PI double-fluorescence staining. Nrf2 inhibitor ML385 was used to verify the regulation of TP on Nrf2.Results: TP improved renal function and histopathological injury of DN mice, alleviated podocytes injury, reduced OS and ROS by activating the Nrf2/heme oxygenase-1 (HO-1) pathway, and weakened pyroptosis by inhibiting the nod-like receptor (NLR) family pyrin domain containing 3 (NLRP3) inflammasome pathway. In vitro experiments further verified the inhibition of TP on OS and pyroptosis by mediating the Nrf2/HO-1 and NLRP3 inflammasome pathways. Inhibition of Nrf2 reversed the protective effect of TP on MPC5 cells.Conclusions: Overall, TP alleviated podocyte injury in DN by inhibiting OS and pyroptosis via Nrf2/ROS/NLRP3 axis.

Berberine ameliorates renal interstitial inflammation and fibrosis in mice with unilateral ureteral obstruction

Berberine acts via multiple pathways to alleviate fibrosis in various tissues and shows renoprotective effects. However, its role and underlying mechanisms in renal fibrosis remain unclear. Herein, we aimed to investigate the protective effects and molecular mechanisms of berberine against unilateral ureteric obstruction-induced renal fibrosis. The results indicated that berberine treatment (50 mg/kg/day) markedly alleviated histopathological alterations, collagen deposition and inflammatory cell infiltration in kidney tissue and restored mouse renal function. Mechanistically, berberine intervention inhibited NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation and the levels of the inflammatory cytokine IL-1β in the kidneys of unilateral ureteric obstruction mice. In addition, berberine relieved unilateral ureteric obstruction-induced renal injury by activating adenosine monophosphate-activated protein kinase (AMPK) signalling and promoting fatty acid β-oxidation. In vitro models showed that berberine treatment prevented the TGF-β1-induced profibrotic phenotype of hexokinase 2 (HK-2) cells, characterized by loss of an epithelial phenotype (alpha smooth muscle actin [α-SMA]) and acquisition of mesenchymal marker expression (E-cadherin), by restoring abnormal fatty acid β-oxidation and upregulating the expression of the fatty acid β-oxidation related-key enzymes or regulators (phosphorylated-AMPK, peroxisome proliferator activated receptor alpha [PPARα] and carnitine palmitoyltransferase 1A [CPT1A]). Collectively, berberine alleviated renal fibrosis by inhibiting NLRP3 inflammasome activation and protected tubular epithelial cells by reversing defective fatty acid β-oxidation. Our findings might be exploited clinically to provide a potential novel therapeutic strategy for renal fibrosis.

Jiangtang Decoction Ameliorates Diabetic Kidney Disease Through the Modulation of the Gut Microbiota

PURPOSE

This study aimed to elucidate the impact of Jiangtang decoction (JTD) on diabetic kidney disease (DKD) and its association with alterations in the gut microbiota.

METHODS

Using a diabetic mouse model (KK-Ay mice), daily administration of JTD for eight weeks was undertaken. Weekly measurements of body weight and blood glucose were performed, while kidney function, uremic toxins, inflammation factors, and fecal microbiota composition were assessed upon sacrifice. Ultra-structural analysis of kidney tissue was conducted to observe the pathological changes.

RESULTS

The study findings demonstrated that JTD improve metabolism, kidney function, uremic toxins and inflammation, while also exerting a modulatory effect on the gut microbiota. Specifically, the genera Rikenella, Lachnoclostridium, and unclassified_c_Bacilli exhibited significantly increased abundance following JTD treatment, accompanied by reduced abundance of norank_f_Lachnospiraceae compared to the model group. Importantly, Rikenella and unclassified_c_Bacilli demonstrated negative correlations with urine protein levels. Lachnoclostridium and norank_f_Lachnospiraceae were positively associated with creatinine (Cr), indoxyl sulfate (IS) and interleukin (IL)-6. Moreover, norank_f_Lachnospiraceae exhibited positive associations with various indicators of DKD severity, including weight, blood glucose, urea nitrogen (UN), kidney injury molecule-1 (KIM-1) levels, trimethylamine-N-oxide (TMAO), p-cresyl sulfate (pCS), nucleotide-binding oligomerization domain (Nod)-like receptor family pyrin domain-containing 3 (NLRP3) and IL-17A production.

CONCLUSION

These findings suggested that JTD possess the ability to modulate the abundance of Rikenella, Lachnoclostridium, unclassified_c_Bacilli and norank_f_Lachnospiraceae within the gut microbiota. This modulation, in turn, influenced metabolic processes, kidney function, uremic toxin accumulation, and inflammation, ultimately contributing to the amelioration of DKD.

Research progress of NLRP3 inflammasome and its inhibitors with aging diseases

In recent years, a new target closely linked to a variety of diseases has appeared in the researchers' vision, which is the NLRP3 inflammasome. With the deepening of the study of NLRP3 inflammasome, it was found that it plays an extremely important role in a variety of physiological pathological processes, and NLRP3 inflammasome was also found to be associated with some age-related diseases. It is associated with the development of insulin resistance, Alzheimer's disease, Parkinson's, cardiovascular aging, hearing and vision loss. At present, the only clinical approach to the treatment of NLRP3 inflammasome-related diseases is to use anti-IL-1β antibodies, but NLRP3-specific inhibitors may be better than the IL-1β antibodies. This article reviews the relationship between NLRP3 inflammasome and aging diseases: summarizes some of the relevant experimental results reported in recent years, and introduces the biological signals or pathways closely related to the NLRP3 inflammasome in a variety of aging diseases, and also introduces some promising small molecule inhibitors of NLRP3 inflammasome for clinical treatment, such as: ZYIL1, DFV890 and OLT1177, they have excellent pharmacological effects and good pharmacokinetics.

Loganin reduces diabetic kidney injury by inhibiting the activation of NLRP3 inflammasome-mediated pyroptosis

Diabetic kidney disease (DKD) is an essential cause of end-stage renal disease. The ongoing inflammatory response in the proximal tubule promotes the progression of DKD. Timely and effective blockade of the inflammatory process to protect the kidney during DKD progression is a proven strategy. The purpose of this study was to investigate the protective effect of loganin on diabetic nephropathy in vivo and in vitro and whether this effect was related to the inhibition of pyroptosis. The results indicated that loganin reduced fasting blood glucose, blood urea nitrogen and serum creatinine concentrations, and alleviated renal pathological changes in DKD mice. In parallel, loganin downregulated the expression of pyroptosis related proteins in the renal tubules of DKD mice and decreased serum levels of interleukin-1beta (IL-1β) and interleukin-18 (IL-18). Furthermore, in vitro experiments showed that loganin attenuated high glucose-induced HK-2 cell injury by reducing the expression of pyroptosis-related proteins, and cytokine levels were also decreased. These fundings were also confirmed in the polyphyllin VI (PPVI) -induced HK-2 cell pyroptosis model. Loganin reduces high glucose induced HK-2 cells pyroptosis by inhibiting reactive oxygen species (ROS) production and NOD-like receptor protein 3 (NLRP3) inflammasome activation. In conclusion, the inhibition of pyroptosis via inhibition of the NLRP3/Caspase-1/Gasdermin D (GSDMD) pathway might be an essential mechanism for loganin treatment of DKD.

Lactobacillus Plantarum NC8 and its metabolite acetate alleviate type 1 diabetes via inhibiting NLRP3

A healthy organism is the result of host-microbiome co-evolution. Microbial metabolites can also stimulate immune cells to reduce intestinal inflammation and permeability. Gut dysbiosis will lead to a variety of autoimmune diseases, such as Type 1 diabetes (T1D). Most of probiotics, such as Lactobacillus casei, Lactobacillus reuteri, Bifidobacterium bifidium, and Streptococcus thermophiles, can improve the intestinal flora structure of the host, reduce intestinal permeability, and relieve symptoms of T1D patients if ingested above probiotics in sufficient amounts. Lactobacillus Plantarum NC8, a kind of Lactobacillus, whether it has an effect on T1D, and the mechanism of it regulating T1D is still unclear. As a member of the inflammatory family, NLRP3 inflammasome can enhance inflammatory responses by promoting the production and secretion of proinflammatory cytokines. Many previous studies had shown that NLRP3 also plays an important role in the development of T1D. When the NLRP3 gene is deleted, the disease progression of T1D will be delayed. Therefore, this study investigated whether Lactobacillus Plantarum NC8 can alleviate T1D by regulating NLRP3. The results demonstrated that Lactobacillus Plantarum NC8 and its metabolites acetate play a role in T1D by co-modulating NLRP3. Lactobacillus Plantarum NC8 and acetate can reduce the damage of T1D in the model mice, even if orally administered them in the early stage of T1D. The number of Th1/Th17 cells in the spleen and pancreatic lymph nodes (PLNs) of T1D mice were significantly reduced by oral Lactobacillus Plantarum NC8 or acetate. The expression of NLRP3 in the pancreas of T1D mice or murine macrophages of inflammatory model were significantly inhibited by treatment with Lactobacillus Plantarum NC8 or acetate. In addition, the number of macrophages in the pancreas were significantly reduced by the treatment with Lactobacillus Plantarum NC8 or acetate. In summary, this study indicated that the regulatory mechanism of Lactobacillus Plantarum NC8 and its metabolite acetate to T1D maybe via inhibiting NLRP3 and provides a novel insights into the mechanism of the alleviated role of probiotics to T1D.

The influence of angiopoietin-like protein 3 on macrophages polarization and its effect on the podocyte EMT in diabetic nephropathy

Background

Podocyte injury, which involves the podocyte epithelial-mesenchymal transition (EMT) process, is a crucial factor contributing to the progression of diabetic nephropathy (DN) and proteinuria. Our study aimed to examine the protective properties of Angiopoietin-like protein 3 (Angptl3) knockout on podocyte damage and macrophage polarization in DN mice and podocytes treated with HG. Furthermore, we also sought to investigate the underlying molecular mechanism responsible for these effects.

Methods

DN was induced in B6;129S5 mice through intraperitoneal injection of 40 mg/kg of streptozotocin (STZ). Subsequently, the changes in renal function, podocyte apoptosis, inflammatory factors (tumor necrosis factor-α [TNF-α], interleukin-6 [IL-6], and interleukin-1β [IL-1β]), IL-10, TGF-β1, IL-1Ra, IL-10Ra, and nephrin were evaluated. Moreover, we investigated the mechanism underlying the role of Angptl3 in macrophages polarization, podocyte injury, podocyte EMT.

Results

Our findings revealed that Angptl3 knockout significantly attenuated STZ or HG-induced renal dysfunction and podocyte EMT. In both in vivo and in vitro studies, Angptl3 knockout led to (1) promote the transformation of M1 type macrophages into M2 type macrophages; (2) amelioration of the reduced expression of nephrin, synaptopodin, and podocin; (3) inhibition of NLRP3 inflammasome activation and release of IL-1β; and (4) regulation of α-SMA expression via the macrophage polarization. (5) After HG treatment, there was an increase in pro-inflammatory factors and foot cell damage. These changes were reversed upon Angptle knockdown.

Conclusion

Our study suggests that the knockout of Angptl3 alleviates podocyte EMT and podocyte injury by regulating macrophage polarization.

Pyroptosis in renal inflammation and fibrosis: current knowledge and clinical significance

Pyroptosis is a novel inflammatory form of regulated cell death (RCD), characterized by cell swelling, membrane rupture, and pro-inflammatory effects. It is recognized as a potent inflammatory response required for maintaining organismal homeostasis. However, excessive and persistent pyroptosis contributes to severe inflammatory responses and accelerates the progression of numerous inflammation-related disorders. In pyroptosis, activated inflammasomes cleave gasdermins (GSDMs) and generate membrane holes, releasing interleukin (IL)-1β/18, ultimately causing pyroptotic cell death. Mechanistically, pyroptosis is categorized into caspase-1-mediated classical pyroptotic pathway and caspase-4/5/11-mediated non-classical pyroptotic pathway. Renal fibrosis is a kidney disease characterized by the loss of structural and functional units, the proliferation of fibroblasts and myofibroblasts, and extracellular matrix (ECM) accumulation, which leads to interstitial fibrosis of the kidney tubules. Histologically, renal fibrosis is the terminal stage of chronic inflammatory kidney disease. Although there is a multitude of newly discovered information regarding pyroptosis, the regulatory roles of pyroptosis involved in renal fibrosis still need to be fully comprehended, and how to improve clinical outcomes remains obscure. Hence, this review systematically summarizes the novel findings regarding the role of pyroptosis in the pathogenesis of renal fibrosis and discusses potential biomarkers and drugs for anti-fibrotic therapeutic strategies.

Cell type-specific roles of NLRP3, inflammasome-dependent and -independent, in host defense, sterile necroinflammation, tissue repair, and fibrosis

The NLRP3 inflammasome transforms a wide variety of infectious and non-infectious danger signals that activate pro-inflammatory caspases, which promote the secretion of IL-1β and IL-18, and pyroptosis, a pro-inflammatory form of cell necrosis. Most published evidence documents the presence and importance of the NLRP3 inflammasome in monocytes, macrophages, and neutrophils during host defense and sterile forms of inflammation. In contrast, in numerous unbiased data sets, NLRP3 inflammasome-related transcripts are absent in non-immune cells. However, an increasing number of studies report the presence and functionality of the NLRP3 inflammasome in almost every cell type. Here, we take a closer look at the reported cell type-specific expression of the NLRP3 inflammasome components, review the reported inflammasome-dependent and -independent functions, and discuss possible explanations for this discrepancy.

Does hand stiffness reflect internal organ fibrosis in diabetes mellitus?

Fibrosis leads to irreversible stiffening of tissue and loss of function, and is a common pathway leading to morbidity and mortality in chronic disease. Diabetes mellitus (both type 1 and type 2 diabetes) are associated with significant fibrosis in internal organs, chiefly the kidney and heart, but also lung, liver and adipose tissue. Diabetes is also associated with the diabetic cheirarthropathies, a collection of clinical manifestations affecting the hand that include limited joint mobility (LJM), flexor tenosynovitis, Duypuytren disease and carpal tunnel syndrome. Histo-morphologically these are profibrotic conditions affecting various soft tissue components in the hand. We hypothesize that these hand manifestations reflect a systemic profibrotic state, and are potential clinical biomarkers of current or future internal organ fibrosis. Epidemiologically, there is evidence that fibrosis in one organ associates with fibrosis with another; the putative exposures that lead to fibrosis in diabetes (advanced glycation end product deposition, microvascular disease and hypoxia, persistent innate inflammation) are 'systemic'; a common genetic susceptibility to fibrosis has also been hinted at. These data suggest that a subset of the diabetic population is susceptible to multi-organ fibrosis. The hand is an attractive biomarker to clinically detect this susceptibility, owing to its accessibility to physical examination and exposure to repeated mechanical stresses. Testing the hypothesis has a few pre-requisites: being able to measure hand fibrosis in the hand, using clinical scores or imaging based scores, which will facilitate looking for associations with internal organ fibrosis using validated methodologies for each. Longitudinal studies would be essential in delineating fibrosis trajectories in those with hand manifestations. Since therapies reversing fibrosis are few, the onus lies on identification of a susceptible subset for preventative measures. If systematically validated, clinical hand examination could provide a low-cost, universally accessible and easily reproducible screening step in selecting patients for clinical trials for fibrosis in diabetes.

STING deletion alleviates podocyte injury through suppressing inflammation by targeting NLRP3 in diabetic kidney disease

An increasing number of studies have shown that immune inflammatory response plays a vital role in diabetic kidney disease (DKD). Nod-like receptor protein 3 (NLRP3) inflammasome-dependent inflammatory response is a key mechanism in the initiation and development of DKD. The stimulator of interferon genes (STING) is an adaptor protein that can drive noninfectious inflammation and pyroptosis. However, the mechanism of STING regulating immune inflammation and the interaction with NLRP3-dependent pyroptosis in high glucose state still remains unclear. This study evaluated the potential role of STING in high glucose (HG)-induced podocyte inflammation response. STING expression was significantly increased in db/db mice, STZ-treated diabetic mice, and HG-treated podocytes. Podocyte-specific deletion of STING alleviated podocyte injury, renal dysfunction, and inflammation in STZ-induced diabetic mice. STING inhibitor (H151) administration ameliorated inflammation and improved renal function in db/db mice. STING deletion in podocytes attenuated the activation of the NLRP3 inflammasome and podocyte pyroptosis in STZ-induced diabetic mice. In vitro, modulated STING expression by STING siRNA alleviated pyroptosis and NLRP3 inflammasome activation in HG-treated podocytes. NLRP3 over-expression offset the beneficial effects of STING deletion. These results indicate that STING deletion suppresses podocyte inflammation response through suppressing NLRP3 inflammasome activation and provide evidence that STING may be a potential target for podocyte injury in DKD.

SGLT-2 Inhibitors and the Inflammasome: What's Next in the 21st Century?

The nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome in the kidney and the heart is increasingly being suggested to play a key role in mediating inflammation. In the kidney, NLRP3 activation was associated with the progression of diabetic kidney disease. In the heart, activation of the NLRP3 inflammasome was related to the enhanced release of interleukin-1β (IL-1β) and the subsequent induction of atherosclerosis and heart failure. Apart from their glucose-lowering effects, SGLT-2 inhibitors were documented to attenuate activation of the NLRP3, thus resulting in the constellation of an anti-inflammatory milieu. In this review, we focus on the interplay between SGLT-2 inhibitors and the inflammasome in the kidney, the heart and the neurons in the context of diabetes mellitus and its complications.

The role of pyroptosis in inflammatory diseases

Programmed cell death has crucial roles in the physiological maturation of an organism, the maintenance of metabolism, and disease progression. Pyroptosis, a form of programmed cell death which has recently received much attention, is closely related to inflammation and occurs via canonical, non-canonical, caspase-3-dependent, and unclassified pathways. The pore-forming gasdermin proteins mediate pyroptosis by promoting cell lysis, contributing to the outflow of large amounts of inflammatory cytokines and cellular contents. Although the inflammatory response is critical for the body's defense against pathogens, uncontrolled inflammation can cause tissue damage and is a vital factor in the occurrence and progression of various diseases. In this review, we briefly summarize the major signaling pathways of pyroptosis and discuss current research on the pathological function of pyroptosis in autoinflammatory diseases and sterile inflammatory diseases.

The beneficial effects of astragaloside IV on ameliorating diabetic kidney disease

Diabetic kidney disease (DKD) has become the major cause of chronic kidney disease or end-stage renal disease. There is still a need for innovative treatment strategies for preventing, arresting, treating, and reversing DKD, and a plethora of scientific evidence has revealed that Chinese herbal monomers can attenuate DKD in multiple ways. Astragaloside IV (AS-IV) is one of the active ingredients of Astragalus membranaceus and was selected as a chemical marker in the Chinese Pharmacopeia for quality control purposes. An increasing amount of studies indicate that AS-IV is a promising novel drug for the treatment of DKD. AS-IV has been shown to improve DKD by combating oxidative stress, attenuating endoplasmic reticulum stress, regulating calcium homeostasis, alleviating inflammation, improving vascular function, improving epithelial to mesenchymal transition and so on. This review briefly summarizes the pathogenesis of DKD, systematically reviews the mechanisms by which AS-IV improves DKD, and aims to facilitate related pharmacological research and development to promote the utilization of Chinese herbal monomers in DKD.

Germacrone protects renal tubular cells against ferroptotic death and ROS release by re-activating mitophagy in diabetic nephropathy

Mitophagy is a critical intracellular event during the progression of diabetic nephropathy (DN). Our previous study demonstrated that germacrone has anti-ferroptotic properties and is a potential therapeutic agent for DN. However, the relationship among germacrone, mitophagy, and ferroptosis in DN remains unclear. In this study, the data confirmed that germacrone ameliorates high glucose (HG)-induced ferroptosis through limiting Fe (2+) content and lipid reactive oxygen species (ROS) accumulation in human kidney 2 (HK-2) cells. Germacrone reversed HG-mediated inhibition of mitophagy. Mitophagy inhibition and anabatic mitochondrial ROS abrogate germacrone-mediated protective effects against ferroptotic death, resulting in the subsequent activation of mitochondrial DNA (mtDNA) cytosolic leakage-induced stimulator of interferon response CGAMP interactor 1 (STING) signaling. The combination of a mitochondrial ROS antagonist and germacrone acts synergistically to alleviate the ferroptotic death of tubular cells and DN symptoms. In summary, germacrone ameliorated ferroptotic death in tubular cells by reactivating mitophagy and inhibiting mtDNA-STING signaling in DN. This study provides a novel insight into germacrone-mediated protection against DN progression and further confirms that antioxidant pharmacological strategies facilitate the treatment of DN.

Mitochondrial dysfunction and oxidative stress: Role in chronic kidney disease

Chronic kidney disease (CKD) is associated with a variety of distinct disease processes that permanently change the function and structure of the kidney across months or years. CKD is characterized as a glomerular filtration defect or proteinuria that lasts longer than three months. In most instances, CKD leads to end-stage kidney disease (ESKD), necessitating kidney transplantation. Mitochondrial dysfunction is a typical response to damage in CKD patients. Despite the abundance of mitochondria in the kidneys, variations in mitochondrial morphological and functional characteristics have been associated with kidney inflammatory responses and injury during CKD. Despite these variations, CKD is frequently used to define some classic signs of mitochondrial dysfunction, including altered mitochondrial shape and remodeling, increased mitochondrial oxidative stress, and a marked decline in mitochondrial biogenesis and ATP generation. With a focus on the most significant developments and novel understandings of the involvement of mitochondrial remodeling in the course of CKD, this article offers a summary of the most recent advances in the sources of procured mitochondrial dysfunction in the advancement of CKD. Understanding mitochondrial biology and function is crucial for developing viable treatment options for CKD.

Pathophysiological correlation of arginase-1 in development of type 2 diabetes from obesity in adolescents

BACKGROUND

There is great interest to understand causal pathophysiological correlation between obesity and diabetes mellitus (DM). Vascular endothelial dysfunction is crucially involved in pathogenesis of vascular complications in DM. Recently, increased arginase expression and activity have been described as underlying mechanisms of endothelial dysfunction in DM and vascular inflammation in obesity. By limiting L-arginine bioavailability to endothelial nitric oxide synthase (NOS III), nitric oxide production is potentially impaired.

METHODS

We investigated the impact of plasma from diabetic and obese adolescents on arginase and NOS III expression in cultured human endothelial cells (ECs). A total of 148 male adolescents participated in this study including 18 obese, 28 type 1-, 28 type 2-DM patients, and 74 age-matched healthy volunteers.

RESULTS

A concurrent increase in arginase-1 (1.97-fold) and decrease in NOS III expression (1.45-fold) was observed in ECs exposed to type 2 diabetic plasma compared to control subjects. ECs incubated with type 1 DM plasma had a diminished NOS III level without impact on arginase-1 expression. Urea-assay featured an increased arginase activity in treated ECs with type 1- or 2-DM plasma. Despite increased pro-inflammatory cytokines and chemokines in obese plasma, arginase-1 expression/activity did not change in treated ECs. However, NOS III expression was significantly reduced. Pearson analysis revealed positive correlation between arginase-1, but not NOS III, expression with FBS in ECs treated with type 2-DM plasma.

CONCLUSIONS

Our data demonstrate that increased arginase-1 expression/activity in ECs, as critical pathogenic factor is correlated with development of obesity-related type 2-DM and linked vascular disease.

Therapeutic potential of artemisinin and its derivatives in managing kidney diseases

Artemisinin, an antimalarial traditional Chinese herb, is isolated from Artemisia annua. L, and has shown fewer side effects. Several pieces of evidence have demonstrated that artemisinin and its derivatives exhibited therapeutic effects on diseases like malaria, cancer, immune disorders, and inflammatory diseases. Additionally, the antimalarial drugs demonstrated antioxidant and anti-inflammatory activities, regulating the immune system and autophagy and modulating glycolipid metabolism properties, suggesting an alternative for managing kidney disease. This review assessed the pharmacological activities of artemisinin. It summarized the critical outcomes and probable mechanism of artemisinins in treating kidney diseases, including inflammatory, oxidative stress, autophagy, mitochondrial homeostasis, endoplasmic reticulum stress, glycolipid metabolism, insulin resistance, diabetic nephropathy, lupus nephritis, membranous nephropathy, IgA nephropathy, and acute kidney injury, suggesting the therapeutic potential of artemisinin and its derivatives in managing kidney diseases, especially the podocyte-associated kidney diseases.