Postprandial Hyperlipidemia: Its Pathophysiology, Diagnosis, Atherogenesis, and Treatments.

Postprandial hyperlipidemia showing postprandial increases in serum triglyceride (TG) is associated with the development of atherosclerotic cardiovascular disease (ASCVD). To diagnose postprandial hyperlipidemia, the oral fat loading test (OFLT) should be performed; however, this test is very time-consuming and is difficult to perform. Elevated serum TG levels reflect an increase in TG-rich lipoproteins (TRLs), such as chylomicrons (CM), very low-density lipoproteins (VLDL), and their remnants (CM remnants [CMRs] and VLDL remnants [VLDLRs]). Understanding of elevation in CMR and/or VLDLR can lead us to understand the existence of postprandial hyperlipidemia. The measurement of apo B48, which is a constituent of CM and CMR; non-fasting TG, which includes TG content in all lipoproteins including CM and CMR; non-high-density lipoprotein cholesterol (non-HDL-C), which includes TRLs and low-density lipoprotein; and remnant cholesterol are useful to reveal the existence of postprandial hyperlipidemia. Postprandial hyperlipidemia is observed in patients with familial type III hyperlipoproteinemia, familial combined hyperlipidemia, chronic kidney disease, metabolic syndrome and type 2 diabetes. Postprandial hyperlipidemia is closely related to postprandial hyperglycemia, and insulin resistance may be an inducing and enhancing factor for both postprandial hyperlipidemia and postprandial hyperglycemia. Remnant lipoproteins and metabolic disorders associated with postprandial hyperlipidemia have various atherogenic properties such as induction of inflammation and endothelial dysfunction. A healthy diet, calorie restriction, weight loss, and exercise positively impact postprandial hyperlipidemia. Anti-hyperlipidemic drugs such pemafibrate, fenofibrate, bezafibrate, ezetimibe, and eicosapentaenoic acid have been shown to improve postprandial hyperlipidemia. Anti-diabetic drugs including metformin, alpha-glucosidase inhibitors, pioglitazone, dipeptidyl-peptidase-4 inhibitors and glucagon-like peptide 1 analogues have been shown to ameliorate postprandial hyperlipidemia. Although sodium glucose cotransporter-2 inhibitors have not been proven to reduce postprandial hyperlipidemia, they reduced fasting apo B48 and remnant lipoprotein cholesterol. In conclusion, it is important to appropriately understand the existence of postprandial hyperlipidemia and to connect it to optimal treatments. However, there are some problems with the diagnosis for postprandial hyperlipidemia. Postprandial hyperlipidemia cannot be specifically defined by measures such as TG levels 2 h after a meal. To study interventions for postprandial hyperlipidemia with the outcome of preventing the onset of ASCVD, it is necessary to define postprandial hyperlipidemia using reference values such as IGT.

Metabolic-Dysfunction-Associated Steatotic Liver Disease-Its Pathophysiology, Association with Atherosclerosis and Cardiovascular Disease, and Treatments.

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a chronic liver disease that affects more than a quarter of the global population and whose prevalence is increasing worldwide due to the pandemic of obesity. Obesity, impaired glucose metabolism, high blood pressure and atherogenic dyslipidemia are risk factors for MASLD. Therefore, insulin resistance may be closely associated with the development and progression of MASLD. Hepatic entry of increased fatty acids released from adipose tissue, increase in fatty acid synthesis and reduced fatty acid oxidation in the liver and hepatic overproduction of triglyceride-rich lipoproteins may induce the development of MASLD. Since insulin resistance also induces atherosclerosis, the leading cause for death in MASLD patients is cardiovascular disease. Considering that the development of cardiovascular diseases determines the prognosis of MASLD patients, the therapeutic interventions for MASLD should reduce body weight and improve coronary risk factors, in addition to an improving in liver function. Lifestyle modifications, such as improved diet and increased exercise, and surgical interventions, such as bariatric surgery and intragastric balloons, have shown to improve MASLD by reducing body weight. Sodium glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been shown to improve coronary risk factors and to suppress the occurrence of cardiovascular diseases. Both SGLT2i and GLP-1 have been reported to improve liver enzymes, hepatic steatosis and fibrosis. We recently reported that the selective peroxisome proliferator-activated receptor-alpha (PPARα) modulator pemafibrate improved liver function. PPARα agonists have multiple anti-atherogenic properties. Here, we consider the pathophysiology of MASLD and the mechanisms of action of such drugs and whether such drugs and the combination therapy of such drugs could be the treatments for MASLD.

Use of biologics for systemic sclerosis and systemic sclerosis-associated interstitial lung disease: Information from a Japanese hospital claims database.

OBJECTIVES: Limited information is available on the use of biologics in patients with systemic sclerosis (SSc) or SSc-associated interstitial lung disease (SSc-ILD) in Japan. The types of biologics, treatment duration, treatment prior to biologics, concomitant treatment, and characteristics of patients receiving biologics were investigated. METHODS: We used a Japanese hospital claims database provided by Medical Data Vision Co. (2008-2021). RESULTS: In the database, 1186 of 34,207 SSc patients (3.5%) and 620 of 12,303 SSc-ILD patients (5.0%) received anti-interleukin-6 (anti-IL-6) drugs, anti-tumour necrosis factor (anti-TNF) drugs, abatacept, or rituximab. The most common were anti-IL-6 drugs [used in 35.5% of SSc patients and 38.5% of SSc-ILD patients (tocilizumab, 34.5% and 36.6%)], followed by anti-TNF drugs [31.3% and 26.5% (etanercept, 10.5% and 9.0%; others, <8%)], abatacept (17.5% and 20.6%), and rituximab (15.7% and 14.4%). Among SSc and SSc-ILD patients treated with anti-IL-6 drugs, anti-TNF drugs, or abatacept, the most common immunosuppressive drugs prior to initiation of biologics were methotrexate and tacrolimus. Approximately half of patients receiving anti-IL-6 drugs, anti-TNF drugs, or abatacept continued treatment beyond 1 year. CONCLUSIONS: Our study indicates that off-label biologics have been used in a certain number of SSc or SSc-ILD patients in Japan, with tocilizumab the most common.

Automated Design of Li+ -Conducting Polymer by Quantum-Inspired Annealing.

Automated molecule design by computers is an essential topic in materials informatics. Still, generating practical structures is not easy because of the difficulty in treating material stability, synthetic difficulty, mechanical properties, and other miscellaneous parameters, often leading to the generation of junk molecules. The problem is tackled by introducing supervised/unsupervised machine learning and quantum-inspired annealing. This autonomous molecular design system can help experimental researchers discover practical materials more efficiently. Like the human design process, new molecules are explored based on knowledge of existing compounds. A new solid-state polymer electrolyte for lithium-ion batteries is designed and synthesized, giving a promising room temperature conductivity of 10-5 S cm-1 with reasonable thermal, chemical, and mechanical properties.

Molecular Biological and Clinical Understanding of the Statin Residual Cardiovascular Disease Risk and Peroxisome Proliferator-Activated Receptor Alpha Agonists and Ezetimibe for Its Treatment.

Several randomized, double blind, placebo-controlled trials (RCTs) have demonstrated that low-density lipoprotein cholesterol (LDL-C) lowering by using statins, including high-doses of strong statins, reduced the development of cardiovascular disease (CVD). However, among the eight RCTs which investigated the effect of statins vs. placebos on the development of CVD, 56-79% of patients had the residual CVD risk after the trials. In three RCTs which investigated the effect of a high dose vs. a usual dose of statins on the development of CVD, 78-87% of patients in the high-dose statin arms still had the CVD residual risk after the trials. An analysis of the characteristics of patients in the RCTs suggests that elevated triglyceride (TG) and reduced high-density lipoprotein cholesterol (HDL-C), the existence of obesity/insulin resistance, and diabetes may be important metabolic factors which determine the statin residual CVD risk. To understand the association between lipid abnormalities and the development of atherosclerosis, we show the profile of lipoproteins and their normal metabolism, and the molecular and biological mechanisms for the development of atherosclerosis by high TG and/or low HDL-C in insulin resistance. The molecular biological mechanisms for the statin residual CVD risk include an increase of atherogenic lipoproteins such as small dense LDL and remnants, vascular injury and remodeling by inflammatory cytokines, and disturbed reverse cholesterol transport. Peroxisome proliferator-activated receptor alpha (PPARα) agonists improve atherogenic lipoproteins, reverse the cholesterol transport system, and also have vascular protective effects, such as an anti-inflammatory effect and the reduction of the oxidative state. Ezetimibe, an inhibitor of intestinal cholesterol absorption, also improves TG and HDL-C, and reduces intestinal cholesterol absorption and serum plant sterols, which are increased by statins and are atherogenic, possibly contributing to reduce the statin residual CVD risk.

Atherogenic Lipoproteins for the Statin Residual Cardiovascular Disease Risk.

Randomized controlled trials (RCTs) show that decreases in low-density lipoprotein cholesterol (LDL-C) by the use of statins cause a significant reduction in the development of cardiovascular disease (CVD). However, one of our previous studies showed that, among eight RCTs that investigated the effect of statins vs. a placebo on CVD development, 56-79% of patients had residual CVD risk after the trials. In three RCTs that investigated the effect of a high dose vs. a usual dose of statins on CVD development, 78-87% of patients in the high-dose statin arms still had residual CVD risk. The risk of CVD development remains even when statins are used to strongly reduce LDL-C, and this type of risk is now regarded as statin residual CVD risk. Our study shows that elevated triglyceride (TG) levels, reduced high-density lipoprotein cholesterol (HDL-C), and the existence of obesity/insulin resistance and diabetes may be important metabolic factors that determine statin residual CVD risk. Here, we discuss atherogenic lipoproteins that were not investigated in such RCTs, such as lipoprotein (a) (Lp(a)), remnant lipoproteins, malondialdehyde-modified LDL (MDA-LDL), and small-dense LDL (Sd-LDL). Lp(a) is under strong genetic control by apolipoprotein (a), which is an LPA gene locus. Variations in the LPA gene account for 91% of the variability in the plasma concentration of Lp(a). A meta-analysis showed that genetic variations at the LPA locus are associated with CVD events during statin therapy, independent of the extent of LDL lowering, providing support for exploring strategies targeting circulating concentrations of Lp(a) to reduce CVD events in patients receiving statins. Remnant lipoproteins and small-dense LDL are highly associated with high TG levels, low HDL-C, and obesity/insulin resistance. MDA-LDL is a representative form of oxidized LDL and plays important roles in the formation and development of the primary lesions of atherosclerosis. MDA-LDL levels were higher in CVD patients and diabetic patients than in the control subjects. Furthermore, we demonstrated the atherogenic properties of such lipoproteins and their association with CVD as well as therapeutic approaches.

Association between anti-complement factor H antibodies and renal outcome in primary membranous nephropathy.

AIMS: The complement factor H (CFH) is a regulator for the alternative complement pathway. The prevalence and roles of anti-CFH antibodies in the clinical outcome of primary membranous nephropathy (MN) patients remain unclear. MATERIALS AND METHODS: A total of 106 biopsy-proven kidney disease patients and 18 healthy controls were retrospectively investigated in this study. 36 patients had primary MN and 70 patients were diseased controls (31 minimal change nephrotic syndrome (MCNS), 19 rapidly progressive glomerulonephritis (RPGN), and 20 IgA glomerulonephritis (IgAGN)). Serum anti-CFH antibody titers were measured by enzyme-linked immunosorbent assay. RESULTS: 77.8% of MN patients were positive for anti-CFH antibodies. However, only 27.1% of diseased control patients and 5.6% of healthy controls were positive for anti-CFH antibodies. Moreover, median anti-CFH antibody titers were significantly higher in MN patients (4.69 AU/mL) than in diseased control patients (MCNS patients (0 AU/mL, p < 0.01), RPGN patients (0 AU/mL, p < 0.05), IgAGN patients (0 AU/mL, p < 0.01)), and healthy controls (0 AU/mL, p < 0.01). Anti-CFH antibody titer was selected as an independent unfavorable predictor of renal dysfunction by Cox proportional hazards analysis. CONCLUSION: These data suggest that anti-CFH antibodies may be involved in the deterioration of renal function in primary MN.

Retrospective single-arm cohort study of steroid-dependent minimal change nephrotic syndrome treated with very low-dose rituximab.

AIM: Conclusions regarding the best rituximab (RTX) dose to maintain remission and reduce immunosuppressant dependence in adult patients with steroid-dependent minimal change nephrotic syndrome (MCNS) are inconsistent. We report the first low-dose (< 375 mg/m2 BSA) RTX therapy, administered once every 6 months. MATERIALS AND METHODS: In this retrospective single-arm cohort study, we investigated the safety and efficacy of low-dose RTX therapy to reduce and ultimately stop prednisolone (PSL) and cyclosporine (CyA) treatment. 13 patients (8 men and 5 women; aged 16 - 65 years; 8-year median treatment history; 12 patients concurrently taking CyA) with steroid-dependent MCNS were chosen to maintain remission following low-dose RTX (200 mg/body) administration. RESULTS: The median period of subject observation following the first RTX dosing was 34 months (cumulative RTX dose: 400 - 1,400 mg). RTX significantly reduced PSL and CyA doses during the final observation in each subject (median dose: PSL 15→0 mg/day, p = 0.0002; CyA 80→0 mg/day, p = 0.0005). All patients maintained complete remission after discontinuing both drugs for a median complete remission (CR) maintenance period of 25 months. One patient showed relapse following the first RTX dose, but a temporary increase in PSL and CyA dose restored the remission. No serious RTX-related adverse effects were observed. Even with MCNS remission, peripheral CD19-positive cell count was not depleted in 90.5% of all cases. CONCLUSION: Low-dose RTX therapy appears to be effective in maintaining remission and reducing immunosuppressant doses in patients with steroid-dependent MCNS, which might involve a B-cell-independent mechanism.

Role and expression of non-classical human leukocyte antigen-G in renal transplanted allografts.

BACKGROUND: The non-classical class I molecule human leukocyte antigen-G (HLA-G) has great potential to modulate the immune response. However, the mechanism underlying HLA-G induction remains unknown. Therefore, this study aimed to determine the factors that induce HLA-G expression on proximal tubular epithelial cells (pTECs) in renal transplanted allografts in vivo and in vitro. METHODS: This study included 40 adult Japanese patients with renal allografts (35 and five patients with kidneys from living and deceased donors, respectively) who survived for at least 1 year. We evaluated HLA-G1/5 expression using an immunofluorescence method and investigated the induction of HLA-G expression in primary cultured human pTECs by cytokines and immunosuppressants. RESULTS: The HLA-G expression was identified in the perinuclear region or on the basement membrane of pTECs of renal biopsy tissue in 12 (30%) of 40 patients at 2-4 weeks and at 1 year following transplantation. A reduction of 30% in the estimated glomerular filtration rate was lower in the HLA-G-positive group than that of the negative group (p = 0.016). Cox proportional hazard models also demonstrated that HLA-G1/5 expression on pTECs was an independent predictor of improved renal allograft function (hazard ratio, 0.189; 95% CI 0.041-0.850, p = 0.030). Interferon-beta was the most powerful inducer of HLA-G expression in vitro, whereas the immunosuppressants everolimus, tacrolimus, cyclosporin, and dexamethasone did not induce any expression. CONCLUSION: Unlike immunosuppressants, acquired HLA-G expression might confer long-term renal preservation effects in renal transplanted allografts.

Molecular Biological and Clinical Understanding of the Pathophysiology and Treatments of Hyperuricemia and Its Association with Metabolic Syndrome, Cardiovascular Diseases and Chronic Kidney Disease.

Uric acid (UA) is synthesized mainly in the liver, intestines, and vascular endothelium as the end product of an exogenous purine from food and endogenously from damaged, dying, and dead cells. The kidney plays a dominant role in UA excretion, and the kidney excretes approximately 70% of daily produced UA; the remaining 30% of UA is excreted from the intestine. When UA production exceeds UA excretion, hyperuricemia occurs. Hyperuricemia is significantly associated with the development and severity of the metabolic syndrome. The increased urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) expression, and glycolytic disturbances due to insulin resistance may be associated with the development of hyperuricemia in metabolic syndrome. Hyperuricemia was previously thought to be simply the cause of gout and gouty arthritis. Further, the hyperuricemia observed in patients with renal diseases was considered to be caused by UA underexcretion due to renal failure, and was not considered as an aggressive treatment target. The evidences obtained by basic science suggests a pathogenic role of hyperuricemia in the development of chronic kidney disease (CKD) and cardiovascular diseases (CVD), by inducing inflammation, endothelial dysfunction, proliferation of vascular smooth muscle cells, and activation of the renin-angiotensin system. Further, clinical evidences suggest that hyperuricemia is associated with the development of CVD and CKD. Further, accumulated data suggested that the UA-lowering treatments slower the progression of such diseases.

Multi-Organ Protective Effects of Sodium Glucose Cotransporter 2 Inhibitors.

Sodium glucose cotransporter 2 inhibitors (SGLT2i) block the reabsorption of glucose by inhibiting SGLT2, thus improving glucose control by promoting the renal excretion of glucose, without requiring insulin secretion. This pharmacological property of SGLT2i reduces body weight and improves insulin resistance in diabetic patients. Such beneficial metabolic changes caused by SGLT2i are expected to be useful not only for glucose metabolism, but also for the protection for various organs. Recent randomized controlled trials (RCTs) on cardiovascular diseases (EMPA-REG OUTCOME trial and CANVAS program) showed that SGLT2i prevented cardiovascular death and the development of heart failure. RCTs on renal events (EMPA-REG OUTCOME trial, CANVAS program, and CREDENCE trial) showed that SGLT2i suppressed the progression of kidney disease. Furthermore, SGLT2i effectively lowered the liver fat content, and our study demonstrated that SGLT2i reduced the degree of hepatic fibrosis in patients at high-risk of hepatic fibrosis. Such promising properties of SGLT2i for cardiovascular, renal, and hepatic protection provide us the chance to think about the underlying mechanisms for SGLT2i-induced improvement of multiple organs. SGLT2i have various mechanisms for organ protection beyond glucose-lowering effects, such as an increase in fatty acids utilization for hepatic protection, osmotic diuresis for cardiac protection, an improvement of insulin resistance for anti-atherogenesis, and an improvement of tubuloglomerular feedback for renal protection.

Changes in double-strand DNA breaks predict delayed graft function (DGF) in Japanese renal allograft recipients.

BACKGROUND: Although delayed graft function (DGF) is a serious complication following kidney transplantation, a reliable and early diagnostic test is lacking to identify the grade of DGF. METHODS: We investigated changes in double-strand DNA breaks (DSBs), and factors related to DGF, such as ischemic times at transplantation and serum creatinine (sCr) levels. DSBs were detected by phospho-histone H2A.X (γ-H2AX) expression and cellular regeneration by Ki-67 before (0 h) and 1 h after allograft reperfusion (1 h) in each subject. RESULTS: The expression of γ-H2AX or Ki-67 at 0 h showed no difference between the living and deceased donors. γ-H2AX at 1 h decreased in the living donors, but increased in the deceased donors compared with that of 0 h(p = 0.017). Changes (Δ) in γ-H2AX between 0 and 1 h were different among subgroups, i.e., immediate function, slow graft function with dialysis < 7 days, DGF with dialysis < 4 weeks, severe DGF with dialysis > 4 weeks, or primary non-function (PNF) (p = 0.04). Severe DGF and PNF cases showed greater increase in Δγ-H2AX (p = 0.019), and were distinguished by > 12% of Δγ-H2AX at 100% sensitivity and 88.2% specificity (ROC analysis, AUC: 0.922, p = 0.023). In a multivariate regression analysis, donor sCr and Δγ-H2AX were two main predictors of the grade of DGF (p = 0.002). The expression of Ki-67 was very low at both 0 h and 1 h. CONCLUSION: The combination of donor sCr and Δγ-H2AX from 0 to 1 h after reperfusion may predict severe DGF and PNF in the early phase.

Glomerular mannose-binding lectin deposition in intrinsic antigen-related membranous nephropathy.

Background: The M-type phospholipase A2 receptor (PLA2R) and thrombospondin type-1 domain-containing 7A (THSD7A) were identified as intrinsic antigens in primary membranous nephropathy (MN). Complement activation via the lectin pathway in intrinsic antigen-related MN is still unclear. Methods: We retrospectively enrolled 60 primary Japanese MN patients and detected activated complement pathways by staining complement proteins in glomerular deposition. According to the findings of PLA2R and THSD7A staining in glomeruli, they were classified into intrinsic antigen-related or -unrelated MN. We evaluated clinicopathological characteristics and predictors of clinical outcomes in intrinsic antigen-related MN. Results: Thirty-nine (65%) patients had PLA2R in glomerular deposits and two (3.3%) patients had THSD7A. One of them had both PLA2R and THSD7A (double positive). Forty patients were classified into the intrinsic antigen-related group. The other 20 patients were negative for both antigens (unrelated group). The prevalence and staining intensity of mannose-binding lectin (MBL) deposits were much higher in the intrinsic antigen-related group [55% versus 20%, P < 0.010, 1.0 (interquartile range 1.0-2.0) versus 1.0 (0.0-1.0), P = 0.01, respectively]. The staining intensity of MBL in glomeruli also correlated with the IgG4 staining intensity. In intrinsic antigen-related MN, MBL staining intensity was an unfavorable predictor for remission of proteinuria [hazard ratio (HR) 0.40, P < 0.01] and renal dysfunction (HR 3.81, P = 0.01) in Cox proportional hazards analysis. Moreover, the glomerular MBL-positive group showed more severe interstitial fibrosis and worse clinical outcomes. Conclusions: Intrinsic antigen-related MN was more strongly associated with complement activation by the lectin pathway, which may contribute to a less favorable clinical outcome.

Circulating and renal expression of HLA-G prevented chronic renal allograft dysfunction in Japanese recipients.

BACKGROUND: Although the risk of acute rejection has been studied in renal transplanted patients, there is little data about the long-term renal survival effects of non-classical human leukocyte antigen class I (HLA-G) in Japanese patients. METHOD: We investigated the changes in the estimated glomerular filtration rate (eGFR) for Japanese, and factors affecting the eGFR in 141 adult Japanese subjects whose allografts had survived for at least 1 year. Clinical background data, gender, HLA matching status, the total ischemic time, ABO incompatibility, immunosuppressive therapy, and the serum soluble(s) HLA-G5 level were examined. In addition, renal biopsy specimens from 32 cases, which were obtained before, or 2-4 weeks or one year after the transplant were also evaluated for HLA-G1/5 expression using monoclonal anti-HLA-G antibodies (clone 87G or 4H84). RESULTS: The rates of change per year in the median eGFR (ΔeGFR) and sHLA-G5 were -1.5 ml/min/1.73 m2/year and 11.8 ng/ml, respectively. A positive correlation was detected between the ΔeGFR and sHLA-G5 (r = 0.188, p = 0.025). In multivariate regression analysis, sHLA-G5 and HLA-matching were significant predictors of an improvement in eGFR (beta for sHLA-G: 0.374, p = 0.009; beta for mismatching: -1.135, p = 0.045). The renal tubular epithelial cells (TEC) in 11 cases showed a perinuclear HLA-G1/5 expression after renal transplantation. The renal HLA-G1/5-positive patients displayed much better ΔeGFR (p < 0.05). In conclusion, the sHLA-G5 level and HLA matching status are independent predictors of renal allograft function, as determined by the ΔeGFR, in Japanese patients. HLA-G1/5 was also detected on TEC in the patients with favorable renal function.

The long-term outcomes of hepatitis C virus core antigen-positive Japanese renal allograft recipients.

BACKGROUND: The impact of hepatitis C virus (HCV) infections on patient long-term survival after renal transplants is unclear. METHOD: To clarify the long-term outcomes of Japanese renal allograft recipients with HCV infections, we studied the cases of 187 patients (118 males and 69 females; 155 living donor cases, and 32 deceased donor cases; median follow-up period: 250 months) who underwent an initial renal transplant at Kanazawa Medical University from 1974 onwards. RESULT: In this cohort, 35 patients (18.7%) were HCV core antigen (Ag)-positive, and 13 of them (37.1%) died (due to liver cirrhosis (4 cases), hepatocellular carcinoma (1 case), fibrosing cholestatic hepatitis due to HCV (1 case), and infections complicated with chronic hepatitis (6 cases)). However, only 14 of the 145 (9.7%) recipients died in the HCV-Ag/HCV antibody (Ab)-negative group. The Kaplan-Meier life table method indicated that the HCV-infected group exhibited significantly lower patient and death-censored allograft survival rates (log-rank test; patient survival: Chi-square: 11.2, p = 0.004; graft survival: Chi-square: 25.7, p < 0.001). The survival rate of the HCV-Ag-positive recipients decreased rapidly at 240 months after the renal transplant procedure. In addition, a Cox proportional hazards model indicated that positivity for the HCV-Ag was the most important independent risk factor for post-renal transplant survival and allograft function [survival: hazard ratio (HR) 3.93 (1.54-10.03), p = 0.004; graft function: HR 2.09 (1.14-3.81), p = 0.016]. CONCLUSION: HCV infection is a harmful risk factor for patient survival (especially at ≥20 years post-renal transplant) and renal allograft function in allograft recipients.

DNA double-strand breaks induced intractable glomerular fibrosis in renal allografts.

BACKGROUNDS: The relationship between DNA damage and glomerular fibrosis in renal allografts remains unclear. METHODS: We examined renal allograft specimens from 35 patients in which DNA double-strand breaks (DSBs) and glomerular fibrosis were detected by phospho-histone H2A.X (γ-H2AX) expression and collagen (COL) types III, IV, and VI accumulation. We also examined the in vitro relationship between DNA damage and COL accumulation by mitomycin C (MMc)-induced DNA damage in human glomerular endothelial cells (HRGEc). RESULTS: The γ-H2AX and COL type VI, which mainly accumulated in the subendothelial and mesangial regions, were positively correlated with the duration of the post-renal transplant (RT) period. In multiple regression analysis, the duration of the post-RT period and cg in the Banff '07 classification were identified as a significant predictor of COL type VI accumulation and γ-H2AX expression in the glomerular capillaries. In addition, the γ-H2AX-positive area was also identified as a predictor of glomerular accumulation of COL type VI. COL type VI was detected in the cytoplasm of the HRGEc, which was secreted into the supernatant after MMc stimulation with γ-H2AX expression. The number of γ-H2AX (-)/COL type VI (+) cells was inversely associated with the number of γ-H2AX (+)/COL type VI (-) cells during 24-h MMc treatment. CONCLUSIONS: Our findings suggest that the long-term RT induces DSBs and HRGEc-secreted COL type VI accumulation in the glomerular capillaries, which might progress to intractable glomerular fibrosis.

Clinical significance of serum and urinary soluble urokinase receptor (suPAR) in primary nephrotic syndrome and MPO-ANCA-associated glomerulonephritis in Japanese.

BACKGROUND: The soluble urokinase receptor (suPAR) has been implicated as a cause of primary focal segmental glomerulosclerosis (FSGS). However, the clinical significance of suPAR in glomerular diseases currently remains unclear. METHODS: In this retrospective single-center cohort study, we investigated serum (s-) and urinary (u-) suPAR in patients with primary nephrotic syndrome (NS) (serum/urine: 37/32 cases) and MPO-ANCA-associated glomerulonephritis (ANCA-GN) (serum/urine: 13/11 cases). RESULTS: In pretreatment s- and u-suPAR, no significant differences were observed between the primary NS and ANCA-GN groups or among the pathological types of primary NS. An inverse correlation was noted between pretreatment s-suPAR and eGFR in the primary NS and ANCA-GN groups. A positive correlation was noted between pretreatment u-suPAR and proteinuria in the primary NS group. Furthermore, time-course changes in s- and u-suPAR over 2 months after therapy were associated with the therapeutic responsiveness of primary NS, particularly the differentiation of MCNS from FSGS (s-suPAR: AUC-ROC = 0.905, p = 0.007; u-suPAR: AUC-ROC = 0.816, p = 0.048). In the ANCA-GN group, a positive correlation was found between pretreatment s-suPAR and clinical severity or crescent formation, whereas u-suPAR was not correlated with these parameters. CONCLUSION: S- and u-suPAR after therapy may serve as clinical markers to judge the treatment response of untreated NS and differentiate MCNS from FSGS, but not in pretreatment patients. S-, but not u-suPAR may predict the severity of and crescent formation in ANCA-GN.

Clinicopathological characteristics of M-type phospholipase A2 receptor (PLA2R)-related membranous nephropathy in Japanese.

BACKGROUND: Recent studies have suggested that assessments of serum antibodies against M-type phospholipase A2 receptor (PLA2R) and the glomerular expression of PLA2R antigen in biopsy specimens are useful for the diagnosis of primary membranous nephropathy (MN). In this study, we assessed both of them and investigated the clinicopathological characteristics of PLA2R-related Japanese MN. METHODS: We retrospectively enrolled 22 primary and 3 secondary Japanese patients whose serum samples and renal specimens were collected before treatment. According to the findings of serum antibodies and antigen in glomeruli, the primary MN patients were classified into PLA2R-related or -unrelated MN. We compared their clinicopathological findings, including IgG subclass staining, and electron microscopic findings, and evaluated the predictors of proteinuria remission. RESULTS: In primary MN, 16 patients (73 %) were classified into the PLA2R-related group, and 6 patients into the PLA2R-unrelated group. There was no significant difference in baseline laboratory data and electron microscopic findings, except for eGFR and serum IgG levels. IgG4-dominant deposition was more common in the related group (63 vs. 0 %). The 10 PLA2R-related patients with dominant IgG4 deposition had a lower rate and prolonged time in remission compared with the 6 PLA2R-related patients with non-dominant IgG4 (log-rank, p = 0.032). Furthermore, dominant IgG4 deposition was an unfavorable predictor of remission by multivariable Cox proportional hazard analysis. CONCLUSIONS: Assessments of both serum PLA2R antibodies and PLA2R antigen in glomeruli were more sensitive for the diagnosis of PLA2R-related MN, and among affected Japanese patients, those with dominant IgG4 deposition had worse clinical outcomes.

Real-world effectiveness of imeglimin in patients with type 2 diabetes: A retrospective longitudinal study in Japan.

OBJECTIVE: To examine the real-world effects of imeglimin on glycemic control and other metabolic factors in patients with type 2 diabetes (T2DM). METHODS: A retrospective longitudinal study was conducted based on a chart review. We recruited patients with T2DM who took imeglimin continuously for at least 3 months. Data on various metabolic parameters were collected at the first prescription of imeglimin and at 3, 6 and 12 months after the initiation of imeglimin. Statistical comparisons were performed using paired t-tests. RESULTS: 68 patients were eligible for this study. HbA1c decreased by 0.7 % at 3 months, 1.1 % at 6 months and 1.0 % by 12 months after the initiation of imeglimin. The decreases in HbA1c were observed regardless of age, gender, body mass index, duration of diabetes, renal function and concomitant use of hypoglycemic agents. There were also significant decreases in body weight, low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and non-HDL-C during imeglimin treatment. CONCLUSIONS: This is the first report showing the long-term effects of imeglimin in a real-world setting. We confirmed the glucose-lowering effects of imeglimin. Furthermore, favorable effects of imeglimin on body weight and serum lipids were also suggested.

A Possible Therapeutic Application of the Selective Inhibitor of Urate Transporter 1, Dotinurad, for Metabolic Syndrome, Chronic Kidney Disease, and Cardiovascular Disease.

The reabsorption of uric acid (UA) is mainly mediated by urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) in the kidneys. Dotinurad inhibits URAT1 but does not inhibit other UA transporters, such as GLUT9, ATP-binding cassette transporter G2 (ABCG2), and organic anion transporter 1/3 (OAT1/3). We found that dotinurad ameliorated the metabolic parameters and renal function in hyperuricemic patients. We consider the significance of the highly selective inhibition of URAT1 by dotinurad for metabolic syndrome, chronic kidney disease (CKD), and cardiovascular disease (CVD). The selective inhibition of URAT1 by dotinurad increases urinary UA in the proximal tubules, and this un-reabsorbed UA may compete with urinary glucose for GLUT9, reducing glucose reabsorption. The inhibition by dotinurad of UA entry via URAT1 into the liver and adipose tissues increased energy expenditure and decreased lipid synthesis and inflammation in rats. Such effects may improve metabolic parameters. CKD patients accumulate uremic toxins, including indoxyl sulfate (IS), in the body. ABCG2 regulates the renal and intestinal excretion of IS, which strongly affects CKD. OAT1/3 inhibitors suppress IS uptake into the kidneys, thereby increasing plasma IS, which produces oxidative stress and induces vascular endothelial dysfunction in CKD patients. The highly selective inhibition of URAT1 by dotinurad may be beneficial for metabolic syndrome, CKD, and CVD.