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To explore the mechanism by which Akkermansia muciniphila cell-free supernatant improves glucose and lipid metabolisms in Caenorhabditis elegans, the present study used different dilution concentrations of Akkermansia muciniphila cell-free supernatant as an intervention for with Caenorhabditis elegans under a high-glucose diet. The changes in lifespan, exercise ability, level of free radicals, and characteristic indexes of glucose and lipid metabolisms were studied. Furthermore, the expression of key genes of glucose and lipid metabolisms was detected by qRT-PCR. The results showed that A. muciniphila cell-free supernatant significantly improved the movement ability, prolonged the lifespan, reduced the level of ROS, and alleviated oxidative damage in Caenorhabditis elegans. A. muciniphila cell-free supernatant supported resistance to increases in glucose and triglyceride induced by a high-glucose diet and downregulated the expression of key genes of glucose metabolism, such as gsy-1, pygl-1, pfk-1.1, and pyk-1, while upregulating the expression of key genes of lipid metabolism, such as acs-2, cpt-4, sbp-1, and tph-1, as well as down-regulating the expression of the fat-7 gene to inhibit fatty acid biosynthesis. These findings indicated that A. muciniphila cell-free supernatant, as a postbiotic, has the potential to prevent obesity and improve glucose metabolism disorders and other diseases.

PURPOSE OF REVIEW Diabetic kidney disease (DKD) is a significant health concern. Innovative strategies to prevent or limit the progression of DKD are urgently needed due to the limitation of existing treatments. KCa3.1, a potassium channel, is involved in a range of biological processes from cell survival to cell death. This review summarizes the current knowledge on the pathophysiological functions of the KCa3.1 channel, specifically its involvement in maintaining mitochondrial function. More specifically, the therapeutic potential of targeting KCa3.1 in DKD is systematically discussed in the review. RECENT FINDINGS Mitochondrial dysfunction contributes to the development and progression of DKD. Accumulating evidence indicates that KCa3.1 dysregulation plays a crucial role in mitochondrial dysfunction, in addition to driving cellular activation, proliferation and inflammation. Recent studies demonstrate that KCa3.1 deficiency improves diabetes-induced mitochondrial dysfunction in DKD, which is attributed to modulation of mitochondrial quality control through mitigating the altered mitochondrial dynamics and restoring abnormal BNIP3-mediated mitophagy. SUMMARY Based on its role in fibrosis, inflammation and mitochondrial dysfunction, pharmacological inhibition of KCa3.1 may offer a promising alternative for the treatment of DKD. Due to its safety profile in humans, the repurposing of senicapoc has the potential to expedite an urgently needed new drug in DKD.

Faecal microbiota transplantation (FMT) has attracted increasing attention as an intervention in many clinical conditions, including autoimmune, enteroendocrine, gastroenterological, and neurological diseases. For years, FMT has been an effective second-line treatment for Clostridium difficile infection (CDI) with beneficial outcomes. FMT is also promising in improving bowel diseases, such as ulcerative colitis (UC). Pre-clinical and clinical studies suggest that this microbiota-based intervention may influence the development and progression of chronic kidney disease (CKD) via modifying a dysregulated gut–kidney axis. Despite the high morbidity and mortality due to CKD, there are limited options for treatment until end-stage kidney disease occurs, which results in death, dialysis, or kidney transplantation. This imposes a significant financial and health burden on the individual, their families and careers, and the health system. Recent studies have suggested that strategies to reverse gut dysbiosis using FMT are a promising therapy in CKD. This review summarises the preclinical and clinical evidence and postulates the potential therapeutic effect of FMT in the management of CKD.

The orientation, distribution, and contact point density of BF (basalt fiber) in the concrete matrix play significant roles in the mechanical properties of BF concrete, but represent a weak point in current research. It is meaningful to study the morphological characteristics of BF in concrete. In this study, the transparent model test and joint blocking method were innovatively adopted to investigate the correlation of dosage with the BF morphological parameters and concrete mechanical properties. A focus on a BF dosage of 0–7.5 kg/m3 and the contribution index of fibers Cf was defined. Furthermore, NMR and CT techniques were used to observe the changes in the microstructure of BF concrete. The experimental results show that the BF contribution index Cf reaches the largest value when the BF content is around 3 kg/m3, approximately 2.7; in this case, the mechanical properties of BF concrete were also optimal, and the Cf was only 2.34 when the BF content was 7.5 kg/m3. NMR and CT test results show that there is a strong correlation between the BF morphological parameters and the distribution of pore structure in the concrete matrix. The overlapping contact of BF clusters led to the penetration of pores, which led the macro-pore proportion to increase dramatically. The increase in the macro-pore proportion is the main reason for the deterioration in concrete performance. In addition, these macro-pores may have adverse effects on the chloride ion permeability of BF concrete.

Chronic kidney disease (CKD) is rising in global prevalence and has become a worldwide public health problem, with adverse outcomes of kidney failure, cardiovascular disease, and premature death. However, current treatments are limited to slowing rather than reversing disease progression or restoring functional nephrons. Hence, innovative strategies aimed at kidney tissue recovery hold promise for CKD therapy. Mesenchymal stem cells (MSCs) are commonly used for regenerative therapy due to their potential for proliferation, differentiation, and immunomodulation. Accumulating evidence suggests that the therapeutic effects of MSCs are largely mediated by paracrine secretion of extracellular vesicles (EVs), predominantly exosomes. MSC-derived exosomes (MSC-Exos) replicate the functions of their originator MSCs via delivery of various genetic and protein cargos to target cells. More recently, MSC-Exos have also been utilized as natural carriers for targeted drug delivery. Therapeutics can be effectively incorporated into exosomes and then delivered to diseased tissue. Thus, MSC-Exos have emerged as a promising cell-free therapy in CKD. In this paper, we describe the characteristics of MSC-Exos and summarize their therapeutic efficacy in preclinical animal models of CKD. We also discuss the potential challenges and strategies in the use of MSC-Exos-based therapies for CKD in the future.

Chronic kidney disease (CKD) is a growing global public health problem. The implementation of evidence-based clinical practices only defers the development of kidney failure. Death, transplantation, or dialysis are the consequences of kidney failure, resulting in a significant burden on the health system. Hence, innovative therapeutic strategies are urgently needed due to the limitations of current interventions. Photobiomodulation (PBM), a form of non-thermal light therapy, effectively mitigates mitochondrial dysfunction, reactive oxidative stress, inflammation, and gut microbiota dysbiosis, all of which are inherent in CKD. Preliminary studies suggest the benefits of PBM in multiple diseases, including CKD. Hence, this review will provide a concise summary of the underlying action mechanisms of PBM and its potential therapeutic effects on CKD. Based on the findings, PBM may represent a novel, non-invasive and non-pharmacological therapy for CKD, although more studies are necessary before PBM can be widely recommended.

Acute kidney injury (AKI) and chronic kidney disease (CKD) are rising in global prevalence and cause significant morbidity for patients. Current treatments are limited to slowing instead of stabilising or reversing disease progression. In this review, we describe mesenchymal stem cells (MSCs) and their constituents, extracellular vesicles (EVs) as being a novel therapeutic for CKD. MSC-derived EVs (MSC-EVs) are membrane-enclosed particles, including exosomes, which carry genetic information that mimics the phenotype of their cell of origin. MSC-EVs deliver their cargo of mRNA, miRNA, cytokines, and growth factors to target cells as a form of paracrine communication. This genetically reprograms pathophysiological pathways, which are upregulated in renal failure. Since the method of exosome preparation significantly affects the quality and function of MSC-exosomes, this review compares the methodologies for isolating exosomes from MSCs and their role in tissue regeneration. More specifically, it summarises the therapeutic efficacy of MSC-EVs in 60 preclinical animal models of AKI and CKD and the cargo of biomolecules they deliver. MSC-EVs promote tubular proliferation and angiogenesis, and inhibit apoptosis, oxidative stress, inflammation, the epithelial-to-mesenchymal transition, and fibrosis, to alleviate AKI and CKD. By reprogramming these pathophysiological pathways, MSC-EVs can slow or even reverse the progression of AKI to CKD, and therefore offer potential to transform clinical practice.

Mitochondria are critical organelles that play a key role in cellular metabolism, survival, and homeostasis. Mitochondrial dysfunction has been implicated in the pathogenesis of diabetic kidney disease. The function of mitochondria is critically regulated by several mitochondrial protein kinases, including the phosphatase and tensin homolog (PTEN)-induced kinase 1 (PINK1). The focus of PINK1 research has been centered on neuronal diseases. Recent studies have revealed a close link between PINK1 and many other diseases including kidney diseases. This review will provide a concise summary of PINK1 and its regulation of mitochondrial function in health and disease. The physiological role of PINK1 in the major cells involved in diabetic kidney disease including proximal tubular cells and podocytes will also be summarized. Collectively, these studies suggested that targeting PINK1 may offer a promising alternative for the treatment of diabetic kidney disease.

It is well-known that all progressive chronic kidney disease (CKD) is pathologically characterized by tubulointerstitial fibrosis process. Multiple studies have shown the critical role of inflammation and fibrosis in the development of CKD. Hence strategies that target inflammatory and fibrotic signaling pathways may provide promising opportunities to protect against renal fibrosis. Metformin has been used as the first-line glucose-lowering agent to treat patients with type 2 diabetes mellitus (T2DM) for over 50 years. Accumulating evidence suggests the potential for additional therapeutic applications of metformin, including mitigation of renal fibrosis. In this study, the anti-fibrotic effects of metformin independent of its glucose-lowering mechanism were examined in an adenine -induced mouse model of CKD. Expressions of inflammatory markers MCP-1, F4/80 and ICAM, fibrotic markers type IV collagen and fibronectin, and the cytokine TGF-β1 were increased in adenine-induced CKD when compared to control groups and significantly attenuated by metformin treatment. Moreover, treatment with metformin inhibited the phosphorylation of Smad3, ERK1/2, and P38 and was associated with activation of the AMP-activated protein kinase (AMPK) in the kidneys of adenine-treated mice. These results indicate that metformin attenuates adenine-induced renal fibrosis through inhibition of TGF-β1 signaling pathways and activation of AMPK, independent of its glucose-lowering action.

The G protein-coupled CXC chemokine receptor 4 (CXCR4) is a candidate therapeutic target for tissue fibrosis. A fully human single-domain antibody-like scaffold i-body AD-114-PA600 (AD-114) with specific high binding affinity to CXCR4 has been developed. To define its renoprotective role, AD-114 was administrated in a mouse model of renal fibrosis induced by folic acid (FA). Increased extracellular matrix (ECM) accumulation, macrophage infiltration, inflammatory response, TGF-β1 expression, and fibroblast activation were observed in kidneys of mice with FA-induced nephropathy. These markers were normalized or partially reversed by AD-114 treatment. In vitro studies demonstrated AD-114 blocked TGF-β1-induced upregulated expression of ECM, matrix metalloproteinase-2, and downstream p38 mitogen-activated protein kinase (p38 MAPK) and PI3K/AKT/mTOR signaling pathways in a renal proximal tubular cell line. Additionally, these renoprotective effects were validated in a second model of unilateral ureteral obstruction using a second generation of AD-114 (Fc-fused AD-114, also named AD-214). Collectively, these results suggest a renoprotective role of AD-114 as it inhibited the chemotactic function of CXCR4 as well as blocked CXCR4 downstream p38 MAPK and PI3K/AKT/mTOR signaling, which establish a therapeutic strategy for AD-114 targeting CXCR4 to limit renal fibrosis.

Receptor-interacting protein kinase-3 (RIPK3) is a multifunctional regulator of cell death and inflammation. RIPK3 controls cellular signalling through the formation of the domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, which is recognised to mediate renal fibrogenesis. The role of RIPK3 in diabetic kidney disease (DKD) induced renal fibrosis has not been previously determined. To define the action of RIPK3 in the development of diabetic kidney disease, wild-type (WT), RIPK3 -/- and endothelium-derived nitric oxide synthase (eNOS)-/- mice were induced to develop diabetes mellitus using multiple low doses of streptozotocin and maintained for 24 weeks. RIPK3 activity and NLRP3 expression were upregulated and fibrotic responses were increased in the kidney cortex of WT mice with established diabetic nephropathy compared to control mice. Consistently, mRNA expression of inflammasome components, as well as transforming growth factor beta 1 (TGFβ1), α smooth muscle actin (α-SMA) and collagen deposition were increased in diabetic kidneys of WT mice compared to control mice. However, these markers were normalised or significantly reversed in kidneys of diabetic RIPK3 -/- mice. Renoprotection was also observed using the RIPK3 inhibitor dabrafenib in eNOS-/- diabetic mice as demonstrated by reduced collagen deposition and myofibroblast activation. These results suggest that RIPK3 is associated with the development of renal fibrosis in DKD due to the activation of the NLRP3 inflammasome. Inhibition of RIPK3 results in renoprotection. Thus, RIPK3 may be a potential target for therapeutic intervention in patients with diabetic kidney disease.

Chronic kidney disease (CKD) is the end result of a plethora of renal insults, including repeated episodes of acute or toxic kidney injury, glomerular, or diabetic kidney disease. It affects a large number of the population worldwide, resulting in significant personal morbidity and mortality and economic cost to the community. Hence it is appropriate to focus on treatment strategies that interrupt the development of kidney fibrosis, the end result of all forms of CKD, in addition to upstream factors that may be specific to certain diseases. However, the current clinical approach to prevent or manage renal fibrosis remains unsatisfactory. The rising importance of receptor-interacting serine/threonine-protein kinase (RIPK) 3 in the inflammatory response and TGF-β1 signaling is increasingly recognized. We discuss here the biological functions of RIPK3 and its role in the development of renal fibrosis.

Renal fibrosis is common to all forms of progressive kidney disease. However, current therapies to limit renal fibrosis are largely ineffective. Phosphorylation of receptor-interacting serine/threonine-protein kinase (RIPK) 3 has been recently suggested to be a key regulator of the pyrin domain containing 3 (NLRP3) inflammasome, which provides new insights into mechanisms of chronic kidney disease (CKD). However, the specific effect of RIPK3 on renal cortical fibrosis has not been fully understood. To study the function of RIPK3, both genetic ablation and pharmacological inhibition of RIPK3 (dabrafenib) were used in the study. Our studies identify that RIPK3 promotes renal fibrosis via the activation of the NLRP3 inflammasome in a mouse model of folic acid-induced nephropathy. Both interventional strategies decreased the renal fibrotic response, and beneficial effects converged on the NLRP3 inflammasome. This study demonstrates a role for RIPK3 as the mediator of renal fibrosis via the upregulation of inflammasome activation. Dabrafenib, as an inhibitor of RIPK3, may be an effective treatment to limit the progression of the tubulointerstitial fibrosis.

We present the preparation of 11 nm polyacrylamide-stabilized polystyrene latex particles for conjugation to a microRNA model by surfactant-free RAFT emulsion polymerization. Our synthetic strategy involved the preparation of amphiphilic polyacrylamide-block-polystyrene copolymers, which were able to self-assemble into polymeric micelles and "grow" into polystyrene latex particles. The surface of these sterically stabilized particles was postmodified with a disulfide-bearing linker for the attachment of the microRNA model, which can be released from the latex particles under reducing conditions. These nanoparticles offer the advantage of ease of preparation via a scaleable process, and the versatility of their synthesis makes them adaptable to a range of applications.

Diabetic kidney disease (DKD) is a life‐limiting condition characterized by progressive and irreversible loss of renal function. Currently, the estimated glomerular filtration rate (eGFR) and albuminuria are used as key markers to define DKD. However, they may not accurately indicate the degree of renal dysfunction and injury. Current therapeutic approaches for DKD, including attainment of blood pressure goals, optimal control of blood glucose and lipid levels, and the use of agents to block the renin‐angiotensin‐aldosterone system (RAAS) can only slow the progression of DKD. Hence, early diagnosis and innovative strategies are needed to both prevent and treat DKD. In recent years, a novel class of noncoding RNA, microRNAs (miRNAs) are reported to be involved in all biological processes, including cellular proliferation, apoptosis, and differentiation. miRNAs are small noncoding RNAs that regulate gene expression by posttranscriptional and epigenetic mechanisms. They are found to be in virtually all body fluids and used successfully as biomarkers for various diseases. Urinary miRNAs correlate with clinical and histologic parameters in DKD and differential urinary miRNA expression patterns have been reported. Kidney fibrosis is the common end stage of various CKD including DKD. Transforming growth factor‐β(TGF‐β) is regarded as the master regulator of kidney fibrosis, which is likely at least in part through regulating miRNA expression. miRNA are widely involved in the progression of DKD via many molecular mechanisms. In this review, the involvement of miRNA in fibrosis, inflammation, hypertrophy, autophagy, endoplasmic reticulum (ER) stress, oxidative stress, insulin resistance, and podocyte injury will be discussed, as these mechanisms are believed to offer new therapeutic targets that can be exploited to develop important treatments for DKD over the next decade.

Despite optimal control of hyperglycaemia, hypertension, and dyslipidaemia, the number of patients with diabetic nephropathy (DN) continues to grow. Strategies to target various signaling pathways to prevent DN have been intensively investigated in animal models and many have been proved to be promising. However, targeting these pathways once kidney disease is established, remain unsatisfactory. The clinical scenario is that patients with diabetes mellitus often present with established kidney damage and need effective treatments to repair and reverse the kidney damage. In this studies, eNOS-/- mice were administered with streptozotocin to induce diabetes. At 24 weeks, at which time we have previously demonstrated albuminuria and pathological changes of diabetic nephropathy, mice were randomised to receive TRAM34 subcutaneously, a highly selective inhibitor of potassium channel KCa3.1 or DMSO (vehicle) for a further 14 weeks. Albuminuria was assessed, inflammatory markers (CD68, F4/80) and extracellular matrix deposition (type I collagen and fibronectin) in the kidneys were examined. The results clearly demonstrate that TRAM34 reduced albuminuria, decreased inflammatory markers and reversed extracellular matrix deposition in kidneys via inhibition of the TGF-β1 signaling pathway. These results indicate that KCa3.1 blockade effectively reverses established diabetic nephropathy in this rodent model and provides a basis for progressing to human studies.

Hyperglycemia induces all isoforms of transforming growth factor β (TGFβ), which in turn play key roles in inflammation and fibrosis that characterize diabetic nephropathy. Sphingosine 1-phosphate (S1P) is a signaling sphingolipid, derived from sphingosine by the action of sphingosine kinase (SK). S1P mediates many biological processes, which mimic TGFβ signaling. To determine the role of SK1 and S1P in inducing fibrosis and inflammation, and the interaction with TGFβ-1, 2 and 3 signalling in diabetic nephropathy, human proximal tubular cells (HK2 cells) were exposed to normal (5 mmol/L) or high (30 mmol/L) glucose or TGFβ-1, -2, -3 ± an SK inhibitor (SKI-II) or SK1 siRNA. Control and diabetic wild type (WT) and SK1(-/-) mice were studied. Fibrotic and inflammatory markers, and relevant downstream signalling pathways were assessed. SK1 mRNA and protein expression was increased in HK2 cells exposed to high glucose or TGFβ1,-2,-3. All TGFβ isoforms induced fibronectin, collagen IV and macrophage chemoattractant protein 1 (MCP1), which were reversed by both SKI-II and SK1 siRNA. Exposure to S1P increased phospho-p44/42 expression, AP-1 binding and NFkB phosphorylation. WT diabetic mice exhibited increased renal cortical S1P, fibronectin, collagen IV and MCP1 mRNA and protein expression compared to SK1(-/-) diabetic mice. In summary, this study demonstrates that inhibiting the formation of S1P reduces tubulointerstitial renal inflammation and fibrosis in diabetic nephropathy.

Purpose of review Hypertension and hyperglycaemia are major risk factors that result in chronic kidney disease (CKD). Achievement of blood pressure goals, optimal control of blood glucose levels and the use of agents to block the renin-angiotensin-aldosterone system slow the progression of CKD. However, not all patients are benefited by these interventions and novel strategies to arrest or reverse the pathological processes inherent in CKD are needed. The therapeutic potential of targeting KCa3.1 in CKD will be discussed in this review. Recent findings Blockade of KCa3.1 ameliorates activation of renal fibroblasts in diabetic mice by inhibiting the transforming growth factor-β1/small mothers against decapentaplegic pathway. A concomitant reduction in nuclear factor-κB activation in human proximal tubular cells under diabetic conditions has been observed. Advanced glycosylated endproducts induce both protein expression and current density of KCa3.1, which, in turn, mediates migration and proliferation of vascular smooth muscle cells via Ca²⁺-dependent signalling pathways. Summary Studies have clearly demonstrated a causal role of chronic hyperglycaemia and hypertension in the development of CKD. However, a large proportion of patients develop end-stage kidney disease despite strict glycaemic control and the attainment of recommended blood pressure goals. Therefore, it is essential to identify and validate novel targets to reduce the development and progression of CKD. Recent findings demonstrate that genetic deletion or pharmacologic inhibition of KCa3.1 significantly reduces the development of diabetic nephropathy in animal models. However, the consequences of blockade of KCa3.1 in preventing and treating established diabetic nephropathy in humans warrants further study.

Progressive tubulointerstitial fibrosis has been recognized as a common pathological process that leads to the progression of all chronic kidney disease (CKD). Innovative strategies are needed to both prevent and treat CKD. Inflammatory and fibrotic signaling pathways play central roles in the progression of CKD regardless of aetiology. Hence, targeting inflammatory and fibrotic responses holds promise to limit renal fibrosis. Metformin has been the most prescribed glucose-lowering medicine worldwide, and its potential for many other therapeutic applications is also being explored intensively. Increasing evidence indicates metformin may limit renal fibrosis. However, the exact mechanisms whereby metformin limits renal injury are not fully understood. The anti-fibrotic effects of metformin, independent of improved glycaemic control was examined in a folic acid-induced mouse model of nephropathy for 14 days. Human proximal tubular cells (HK2 cells) exposed to TGF-β1 were used in in vitro models to examine mechanistic pathways. Folic acid induced nephropathy was associated with the overexpression of inflammatory markers MCP-1, F4/80, type IV collagen, fibronectin and TGF-β1 compared to control groups, which were partially attenuated by metformin treatment. In vitro studies confirmed that metformin inhibited TGF-β1 induced inflammatory and fibrotic responses through Smad3, ERK1/2, and P38 pathways in human renal proximal tubular cells. These results suggest that metoformin attenuates folic acid-induced renal interstitial fibrogenesis through TGF-β1 signaling pathways.

There is an urgent need to identify novel interventions for mitigating the progression of diabetic nephropathy. Diabetic nephropathy is characterized by progressive renal fibrosis, in which tubulointerstitial fibrosis has been shown to be the final common pathway of all forms of chronic progressive renal disease, including diabetic nephropathy. Therefore targeting the possible mechanisms that drive this process may provide novel therapeutics which allow the prevention and potentially retardation of the functional decline in diabetic nephropathy. Recently, the Ca2+-activated K+ channel KCa3.1 (KCa3.1) has been suggested as a potential therapeutic target for nephropathy, based on its ability to regulate Ca2+ entry into cells and modulate Ca2+-signalling processes. In the present review, we focus on the physiological role of KCa3.1 in those cells involved in the tubulointerstitial fibrosis, including proximal tubular cells, fibroblasts, inflammatory cells (T-cells and macrophages) and endothelial cells. Collectively these studies support further investigation into KCa3.1 as a therapeutic target in diabetic nephropathy.

Thioredoxin-interacting protein (TXNIP) expression is ubiquitous and is induced by a variety of cellular stresses, including high intracellular glucose. TXNIP is associated with activation of oxidative stress and tubulointerstitial fibrosis in diabetic nephropathy. Autophagy is a major pathway that delivers damaged proteins and organelles to lysosomes to maintain cellular homeostasis. This study aimed to investigate the dysregulation of autophagy and the regulation of TXNIP on autophagy in renal proximal tubular cells (PTCs) under diabetic conditions. The formation of autophagosomes was measured using transmission electron microscopy, and LC3-II, and the effectiveness of autophagic clearance was determined by p62 expression in diabetic kidney and in human PTCs exposed to high glucose (HG). The results collectively demonstrated increased expression of TXNIP, LC3/LC3-II and p62 in renal tubular cells of mice with diabetic nephropathy and in cultured human PTCs exposed to HG (30 mM/l) for 48 h compared with control. The formation of autophagic vacuoles was increased in HG-induced cells. Furthermore, silencing of TXNIP by siRNA transfection reduced autophagic vacuoles and the expression of LC3-II and p62 in human PTCs exposed to HG compared with control and partially reversed the accumulation of LC3-II and p62 induced by bafilomycin A1 (50 nM/l), a pharmacological inhibitor of autophagy which blocks the fusion of autophagosomes with lysosomes and impairs the degradation of LC3-II and p62. Collectively, these results suggest that hyperglycemia leads to dysfunction of autophagy in renal tubular cells and decreases autophagic clearance. HG-induced overexpression of TXNIP may contribute to the dysfunction of tubular autophagy in diabetes.

Background Fibroblast activation plays a critical role in diabetic nephropathy (DN). The Ca2+-activated K+ channel KCa3.1 mediates cellular proliferation of many cell types including fibroblasts. KCa3.1 has been reported to be a potential molecular target for pharmacological intervention in a diverse array of clinical conditions. However, the role of KCa3.1 in the activation of myofibroblasts in DN is unknown. These studies assessed the effect of KCa3.1 blockade on renal injury in experimental diabetes. Methods As TGF-β1 plays a central role in the activation of fibroblasts to myofibroblasts in renal interstitial fibrosis, human primary renal interstitial fibroblasts were incubated with TGF-β1+/- the selective inhibitor of KCa3.1, TRAM34, for 48 h. Two streptozotocin-induced diabetic mouse models were used in this study: wild-type KCa3.1+/+ and KCa3.1-/- mice, and secondly eNOS-/- mice treated with or without a selective inhibitor of KCa3.1 (TRAM34). Then, markers of fibroblast activation and fibrosis were determined. Results Blockade of KCa3.1 inhibited the upregulation of type I collagen, fibronectin, α-smooth muscle actin, vimentin and fibroblast-specific protein-1 in renal fibroblasts exposed to TGF-β1 and in kidneys from diabetic mice. TRAM34 reduced TGF-β1-induced phosphorylation of Smad2/3 and ERK1/2 but not P38 and JNK MAPK in interstitial fibroblasts. Conclusions These results suggest that blockade of KCa3.1 attenuates diabetic renal interstitial fibrogenesis through inhibiting activation of fibroblasts and phosphorylation of Smad2/3 and ERK1/2. Therefore, therapeutic interventions to prevent or ameliorate DN through targeted inhibition of KCa3.1 deserve further consideration.

The Ca2+-activated K+ channel KCa3.1 mediates cellular signaling processes associated with dysfunction of vasculature. However, the role of KCa3.1 in diabetic nephropathy is unknown. We sought to assess whether KCa3.1 mediates the development of renal fibrosis in two animal models of diabetic nephropathy. Wild-type and KCa3.1−/− mice, and secondly eNOS−/− mice, had diabetes induced with streptozotocin and then were treated with/without a selective inhibitor of KCa3.1 (TRAM34). Our results show that the albumin-to-creatinine ratio significantly decreased in diabetic KCa3.1−/− mice compared with diabetic wild-type mice and in diabetic eNOS−/− mice treated with TRAM34 compared with diabetic mice. The expression of monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule 1 (ICAM1), F4/80, plasminogen activator inhibitor type 1 (PAI-1), and type III and IV collagen significantly decreased (P < 0.01) in kidneys of diabetic KCa3.1−/− mice compared with diabetic wild-type mice. Similarly, TRAM34 reduced the expression of the inflammatory and fibrotic markers described above in diabetic eNOS−/− mice. Furthermore, blocking the KCa3.1 channel in both animal models led to a reduction of transforming growth factor-β1 (TGF-β1) and TGF-β1 type II receptor (TβRII) and phosphorylation of Smad2/3. Our results provide evidence that KCa3.1 mediates renal fibrosis in diabetic nephropathy through the TGF-β1/Smad signaling pathway. Blockade of KCa3.1 may be a novel target for therapeutic intervention in patients with diabetic nephropathy.

MicroRNAs (miRNAs) comprise of a novel class of endogenous small noncoding RNAs that frequently downregulate the expression of target genes. Recent reports suggest that miRNA-200b prevents epithelial-to-mesenchymal transition (EMT) in cancer cells by targeting the E-box binding transcription factors Zinc finger E-box-binding homeobox 1 (ZEB1) and Zinc finger E-box-binding homeobox 2 (ZEB2). About 35% of active fibroblasts are derived from EMT which is central to the development of progressive renal fibrosis. Hence, this study was designed to assess the effect of miRNA-200b on transforming growth factor-β (TGF-β1)-induced fibrotic responses in renal tubular cells. Morphologically, human kidney-2 cells transfected with miRNA-200b retained their epithelial cell characteristics when exposed to TGF-β1. miRNA-200b significantly increased E-cadherin ( P < 0.001) and reduced fibronectin mRNA and protein expression (both P < 0.01) independent of phospho-Smad2/3 and phospho-p38 and p42/44 signaling. Increased E-cadherin expression was associated with decreased expression of ZEB1 and ZEB2 and repression of fibronectin was mediated through direct targeting of the fibronectin mRNA, demonstrated using pMIR luciferase reporter assay and site-directed mutagenesis. These results suggest that miRNA-200b suppresses TGF-β1-induced EMT via inhibition of ZEB1 and ZEB2 and the extracellular matrix protein fibronectin by directing targeting of its 3′UTR mRNA, independent of pathways directly involved in TGF-β1 signaling.

Hyperglycemia upregulates thioredoxin interacting protein (TXNIP) expression, which in turn induces ROS production, inflammatory and fibrotic responses in the diabetic kidney. Dysregulation of autophagy contributes to the development of diabetic nephropathy. However, the interaction of TXNIP with autophagy/mitophagy in diabetic nephropathy is unknown. In this study, streptozotocin-induced diabetic rats were given TXNIP DNAzyme or scrambled DNAzyme for 12 weeks respectively. Fibrotic markers, mitochondrial function and mitochondrial reactive oxygen species (mtROS) were assessed in kidneys. Tubular autophagy and mitophagy were determined in kidneys from both human and rats with diabetic nephropathy. TXNIP and autophagic signaling molecules were examined. TXNIP DNAzyme dramatically attenuated extracellular matrix deposition in the diabetic kidneys compared to the control DNAzyme. Accumulation of autophagosomes and reduced autophagic clearance were shown in tubular cells of human diabetic compared to non-diabetic kidneys, which was reversed by TXNIP DNAzyme. High glucose induced mitochondrial dysfunction and mtROS production and inhibited mitophagy in proximal tubular cells, which was reversed by TXNIP siRNA. TXNIP inhibition suppressed diabetes-induced BNIP3 expression and activation of the mTOR signaling pathway. Collectively, hyperglycemia-induced TXNIP contributes to the dysregulation of tubular autophagy and mitophagy in diabetic nephropathy through activation of the mTOR signaling pathway.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide. However, there is a shortage of suitable diagnostic markers for early stages of NSCLC, and therapeutic targets are limited. Right open reading frame (Rio) kinase 2 (RIOK2) and Nin one binding (NOB1) protein are important accessory factors in ribosome assembly and are highly expressed in malignant tumours; moreover, they interact with each other. However, the RIOK2 expression profile and its clinical significance as well as NOB1's mechanism in NSCLC remain unknown. In this study, NSCLC cell lines and 15 NSCLC tumour tissues (paired with adjacent normal lung tissues) were collected for a real-time quantitative PCR (RT-qPCR) analysis. In addition, 153 NSCLC cases and 27 normal lung tissues were used in an immunohistochemical analysis to evaluate the RIOK2 and NOB1 expression profiles, their clinicopathological factors in NSCLC and their correlations with prognoses. RIOK2 and NOB1 were highly expressed in NSCLC cells and tissues, and their expression profiles were significantly associated with the Tumour Node Metastasis (TNM) clinical stage, lymph node metastasis, and differentiation. RIOK2 expression was correlated with NOB1. The results suggested that simultaneously determining the expression of RIOK2 and NOB1 will improve the diagnostic rate in early stages of NSCLC. Moreover, RIOK2 and NOB1 might be potential targets for NSCLC therapy.

Autophagy is emerging as an important pathway in many diseases including diabetic nephropathy. It is acknowledged that oxidative stress plays a critical role in autophagy dysfunction and diabetic nephropathy and KCa3.1 blockade ameliorates diabetic renal fibrosis through inhibiting TGF-β1 signaling pathway. To identify the role of KCa3.1 in dysfunctional tubular autophagy in diabetic nephropathy, human proximal tubular cells (HK2) transfected with scrambled or KCa3.1 siRNAs were exposed to TGF-β1 for 48 h, then autophagosome formation, the autophagy marker LC3, signaling molecules PI3K, Akt and mTOR and oxidative stress marker nitrotyrosine were examined respectively. In vivo, LC3, nitrotyrosine and phosphorylated mTOR were examined in kidneys of diabetic KCa3.1+/+ and KCa3.1−/− mice. The results demonstrated that TGF-β1 increased the formation of autophagic vacuoles, LC3 expression and phosphorylation of PI3K, Akt and mTOR in scrambled siRNA transfected HK2 cells compared to control cells, which was reversed in KCa3.1 siRNA transfected HK2 cells. In vivo, expression of LC3 and nitrotyrosine and phosphorylation of mTOR were significantly increased in kidneys of diabetic KCa3.1+/+ mice compared to non-diabetic mice, which were attenuated in kidneys of diabetic KCa3.1−/− mice. These results suggest that KCa3.1 activation contributes to dysfunctional tubular autophagy in diabetic nephropathy through PI3K/Akt/mTOR signaling pathways.

Aimed at the support problem of the deep large-section tunnel excavated in high-stress condition with fractured surrounding rock, the different characteristics of the stresses and displacements of the surrounding rock of the tunnel with different section supports and lateral pressure coefficients were analyzed using numerical simulation and theoretical calculation, so was the effect of the height of the double-layered I-section beam on the bearing capacity. Arched with bottom arch superimposed and fully-closed I-section beam suitable for large-section tunnel excavated in high-stress condition with fractured surrounding rock was developed. This support applies fully-closed and horse-shoe shaped structure with I-section beam overlapped and welded and its bearing capacity is 2.5 times higher than frequently-used I-section beam. Underground field testing showed that the deformation of the surrounding rock could be effectively controlled when the secondary arched with bottom arch superimposed and fully-closed I-section beam of high bearing capacity was used.

The aim of the present research was to investigate clinicopathologic correlations of immunohistochemically- demonstrated axin (axis inhibition) and β-catenin expression in primary hepatocellular carcinomas (HCCs), in comparison with paraneoplastic, cirrhotic and normal liver tissues. Variation in Axin expression across groups were significant (P0.01), correlating with alpha fetoprotein (AFP), HBsAg, cancer plugs in the portal vein, and clinical stage of HCCs(P0.05); however, there were no links with sex, age, and tumour size (P0.05). Differences in cell membrane β-catenin expression were also statistically significant (P0.01), again correlated with AFP, HBsAg, cancer plugs in the portal vein, and clinical stage in HCCs (P0.05) but not with sex, age, and tumour size (P0.05). Axin expression levels in tissues with reduced membrane β-catenin were low (P0.05), also being low with nuclear β-catenin expression (P0.05). Axin and β-catenin may play an important role in the genesis and progression of HCC via the Wnt signal transmission pathway. Simultaneous determination of axin, β-catenin, AFP, and HBsAg may be useful for early diagnosis, and metastatic and clinical staging of HCCs.

Hyperglycemia and hypoxia have independent and convergent roles in the development of renal disease. Transforming growth factor-β1(TGF-β1) is a key cytokine promoting the production of extracellular matrix proteins. The cationic-independent mannose 6-phosphate receptor (CI-M6PR) is a membrane protein that binds M6P-containing proteins. A key role is to activate latent TGF-β1. PXS25, a novel CI-MPR inhibitor, has antifibrotic properties in skin fibroblasts, but its role in renal fibrosis is unclear. The aim was to study the role of PXS25 in matrix protein production under high glucose ± hypoxic conditions in human proximal tubule (HK-2) cells. HK-2 cells were exposed to high glucose (30 mM) ± 100 μM PXS25 in both normoxic (20% O2) and hypoxic (1% O2) conditions for 72 h. Cellular fibronectin, collagen IV, and matrix metalloproteinase-2 (MMP-2) and MMP-9 were assessed. Total and active TGF-β1were measured by ELISA. High glucose and hypoxia independently induced TGF-β1production. Active TGF-β1, but not total TGF-β1was reduced with concurrent PXS25 in the presence of high glucose, but not in hyperglycemia+hypoxia conditions. Hyperglycemia induced fibronectin and collagen IV production ( P < 0.05), as did hypoxia, but only hyperglycemia-induced increases in matrix proteins were suppressed by concurrent PXS25 exposure. High glucose induced MMP-2 and -9 in normoxic and hypoxic conditions, which was not modified in the presence of PXS25. High glucose and hypoxia can independently induce endogenous active TGF-β1production in human proximal tubular cells. PXS25 inhibits conversion of high glucose-induced release of active TGF-β1, only in the absence of hypoxia.

Macrophage inflammatory protein-3 alpha (MIP-3α) is known to be upregulated early in the development of diabetic nephropathy (DN). However, the transcriptional regulation of MIP-3α is unknown. We previously demonstrated that the transcription factors KLF6 and PPAR-γ play key roles in regulating renal fibrotic and inflammatory responses to factors inherent in diabetes mellitus. Hence we determined the role of these transcription factors in regulating MIP-3α expression. HK-2 cells and STZ-induced diabetic rats were used. siRNAs, over-expressing constructs and CHIP promoter binding assays were used to determine the role of KLF6 and PPAR-γ in MIP-3α transcriptional regulation. KLF6 overexpression increased MIP-3α which was inhibited by concurrent exposure to PPAR-γ agonists. PPAR-γ agonists attenuated high glucose-induced MIP-3α secretion. Furthermore, MIP-3α secretion was up-regulated in PPAR-γ silenced cells, suggesting both KLF6 and PPAR-γ antagonistically regulate high glucose-induced MIP-3α secretion. The CHIP promoter binding assay confirmed that PPAR-γ binds to the MIP-3α promoter and negatively regulates MIP-3α expression. PPAR-γ agonists increased the binding activity of the PPAR-γ-MIP-3α promoter. In contrast, promoter binding activity decreased in KLF6 over-expressing cells. PPAR-γ decreased in KLF6 over-expressing cells and increased in KLF6 silenced cells, while PPAR-γ siRNA had no effect on KLF6 expression, suggesting that KLF6 acted upstream of PPAR-γ in the regulation of MIP-3α. In diabetic rats, renal MIP-3α and the macrophage marker ED-1 expression increased, which was inhibited by exposure to PPAR-γ agonists. The recognition of MIP-3α as a significant pathogenic mediator in diabetic nephropathy reaffirms the increasingly recognized role of inflammation in the progression of DN. Targeting pro-inflammatory chemokine MIP-3α and its signaling pathways will provide novel strategy to treat diabetic kidney disease.